JP7625238B2 - Power Cycle Test Equipment - Google Patents

Description

The present invention relates to an electrical element testing device and an electrical element testing method for performing power cycle tests on semiconductor elements such as SiC, IGBT, MOS-FET, Gan-FET, and bipolar transistors.

To provide a semiconductor element testing device and a semiconductor element testing method that can efficiently reproduce stresses similar to failure modes in the environment in which semiconductor elements are used, and can evaluate power semiconductor elements and the like with high reliability.

The lifespan of a power semiconductor element can be determined by thermal fatigue caused by heat generation within the power semiconductor element itself, or by thermal fatigue caused by temperature changes in the external environment of the power semiconductor element. There is also a lifespan due to voltage fatigue caused by the voltage applied to the gate insulating film of the power semiconductor element.

Generally, life tests for power semiconductor elements are performed by repeatedly turning current on and off to the semiconductor element. For example, tests are performed by setting an applied voltage and current to the emitter terminal (source terminal) and collector terminal (drain terminal) of the transistor of the semiconductor element, and applying a periodic on-off signal (operation/non-operation signal) to the gate terminal.

The current applied to the semiconductor element during testing is large, at several hundred amperes, and requires low-resistance wiring to avoid heat generation and voltage drop. Because the test current is large, the connections between the semiconductor element and the wiring must be made with low resistance. In addition, there are many types of tests, and the wiring connections must be changed depending on the type of test.

Patent Publication 2014-138488

In conventional semiconductor element testing equipment, tests of power semiconductor elements (transistors, etc.) are performed by turning transistor 117 on and off and passing a constant current Id through the transistor channel.

The test items performed by the semiconductor element test equipment (power cycle test equipment) are diverse, and the connection to the transistor 117 needs to be changed to correspond to the test items.

The constant current Id is often several hundred amperes or more, and the connection wiring 211 and power supply wiring 212 that carry this current must be made of thick wire. In addition, a large current Id flows through the semiconductor element terminal. If there is contact resistance between the semiconductor element terminal and the connection wiring, the contact area will heat up, causing the semiconductor element to break down.

Changing the connections of thick wires to accommodate test items takes a long time, and because it requires work space to change the wiring connections, there is an issue that the test equipment becomes large.

The semiconductor element testing apparatus of the present invention has a connection structure 218 that connects to the element terminal 226 of the semiconductor element to be tested. One end of the connection structure 218 has a contact portion 220 that contacts the element terminal 226, and a peat pipe 223 is attached to the surface of the connection structure 218. The connection structure 218 is electrically connected to the element terminal 226 of the semiconductor element 117 to be tested by inserting it into the opening 216 formed in the partition wall 217 and/or by inserting the connection structure into the groove of the support stand 323.

The semiconductor device testing device of the present invention separates the location (space) within the semiconductor device testing device where the transistor 117 to be tested is placed from the location of the circuit board where the test current for the transistor 117 is generated, the control signal is generated, and the test results are obtained. A partition is provided for separation.

The connection between the transistor to be tested and the circuit board is made by inserting a fork plug 205 (connection plug 205) through an opening 216 provided in the bulkhead 214 and bringing the connection plug 205 into contact with the conductor plate on the circuit board.

Since there is contact resistance at the connection between the element terminal 226 of the transistor 117 to be tested and the connection structure 218, the contact will heat up when a large current flows. In the present invention, since a heat pipe 223 is disposed in the connection structure 218, the generated heat can be efficiently conducted and released. Since the element terminal 226 and the connection structure 218 are structured to be inserted from an opening 216 of the partition wall 217, they can be easily attached and detached to the transistor 117 to be tested, and the connection to the transistor 117 to be tested can be changed in a short time.

A partition 214 is provided to separate the location (space) in the semiconductor device testing device where the transistor 117 is placed from the location on the circuit board where the test current for the transistor 117 is generated, the control signal is generated, and the test results are obtained. A connection plug 205 is inserted through an opening 216 provided in the partition 214, and the connection plug 205 is connected to the conductor plate 204 on the circuit board. There is no need to connect the connection wiring 211 for each test item, and no work space is required to change the wiring connection, making it possible to miniaturize the semiconductor device testing device.

FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of a method for connecting an electric element test apparatus and an electric element according to the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of a method for connecting an electric element test apparatus and an electric element according to the present invention. FIG. 1 is a configuration diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. 1 is a structural diagram and an equivalent circuit diagram of an electric element. 1 is a structural diagram and an equivalent circuit diagram of an electric element. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of a method for connecting an electric element test apparatus and an electric element according to the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a connection structure of the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of a connection portion of the electrical element testing apparatus of the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 1 is a configuration diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. FIG. 2 is an explanatory diagram of an electrical element testing device according to the present invention. 4 is an explanatory diagram of the operation of the electrical element testing apparatus according to the first embodiment of the present invention; FIG. 5 is an explanatory diagram of the operation of the electrical element testing apparatus according to the first embodiment of the present invention. FIG. 5 is an explanatory diagram of the operation of the electrical element testing apparatus according to the first embodiment of the present invention. FIG. 5 is an explanatory diagram of the operation of the electrical element testing apparatus according to the first embodiment of the present invention. FIG. 4 is an explanatory diagram of the operation of the electrical element testing apparatus according to the first embodiment of the present invention; FIG. 7 is an explanatory diagram of the operation of the electrical element testing apparatus according to the second embodiment of the present invention. FIG. 13 is an explanatory diagram of the operation of the electrical element testing apparatus according to the third embodiment of the present invention. FIG. 13 is an explanatory diagram of the operation of the electrical element testing apparatus according to the fourth embodiment of the present invention. FIG. 13 is an explanatory diagram of the operation of the electrical element testing apparatus according to the fourth embodiment of the present invention. FIG. FIG. 2 is an explanatory diagram of a power semiconductor element.

The following describes an electrical element testing device and an electrical element testing method for power cycle testing, etc., according to an embodiment of the present invention, with reference to the attached drawings.

In the embodiments described in the specification, an IGBT will be used as an example of a power semiconductor element. The present invention is not limited to IGBTs, and can be applied to various power semiconductor elements such as SiC, MOSFETs, JFETs, and transistors. Furthermore, the present invention is not limited to transistors, and can also be applied to two-terminal elements such as diodes.

It goes without saying that the present invention is not limited to power semiconductor elements, but can also be applied to electronic elements such as low-power semiconductor elements, signal control semiconductor elements, resistor elements, capacitors, coils, crystal oscillators, thermistors, etc.

In each drawing for explaining the embodiment of the invention, elements having the same function are given the same reference numerals, and the description may be omitted. In addition, the embodiments of the present invention may be combined with each other.

8 is a configuration diagram of a power cycle test apparatus (semiconductor element test apparatus) of the present invention. The power cycle test apparatus has a chiller (cooling/warming device) 136, a heating/cooling plate 134, and a circulating water pipe 135 that circulates water between the heating/cooling plate 134 and the chiller 136. A transistor 117 is mounted on the heating/cooling plate 134 as a semiconductor element to be tested.
The test conditions are set by changing the current Id, the gate voltage Vgs, and the voltage Vce so that the temperature information Tj of the transistor 117 to be tested becomes a predetermined value.

When the temperature information Tj changes, it is determined that the transistor 117 has deteriorated or its characteristics have changed, and the test of the transistor 117 is stopped or the control method is changed.

Note that the current flowing through or applied to transistor 117 is described as a constant current Id, but the present invention is not limited to this. It goes without saying that Id may be a current that changes at a predetermined cycle or time. Also, it is not limited to a current, and may be a voltage.

The change in the characteristics of transistor 117 is judged or determined based on the change in temperature information Tj. In addition, the change in characteristics, reliability, and lifespan of transistor 117 are evaluated based on the time it takes for voltage Vce to reach a predetermined voltage, the time until transistor 117 is destroyed, etc.

In the semiconductor testing method of the present invention, the external conditions are changed according to the deterioration or characteristic changes of transistor 117. For example, if transistor 117 generates heat, the water temperature is lowered. By lowering the water temperature and reducing the current flowing through transistor 117, the deterioration and characteristic changes of transistor 117 do not progress, and as a result, the lifespan of transistor 117 is extended. Therefore, the lifespan and reliability characteristics of transistor 117 for specified set conditions can be quantitatively measured and determined.

The temperature of the transistor 117 is maintained at a specified or predetermined value by heating or cooling the circulating water in the chiller 136. The temperature of the transistor, etc. is also periodically changed in response to the test conditions, and is cooled or heated to a constant value. Temperature information Tj of the test transistor is measured, and the chiller 136 is controlled to maintain the measured temperature information Tj at a constant value.

Chillers are designed to keep the temperature of equipment constant by circulating water or heat transfer medium while controlling its temperature. They are primarily used for cooling, but can also heat as well as cool. They are designed to allow for a variety of temperature controls.

The control rack 131 has a power supply unit 132 that supplies a test current and a test voltage to the transistor 117, and a control circuit 133 that controls the transistor 117 or sets the test conditions.

The control circuit 133 receives temperature information Tj of the transistor 117 and controls the chiller 136 based on the temperature information Tj. Alternatively, the control circuit 133 controls the chiller 136 so that the temperature information Tj becomes a predetermined value.

Note that although circulating water is described in this specification, it is not limited to water. It may be ethylene glycol, glycerin, freon, etc., or forced air cooling. The chiller 136 controls the liquid in the circulating water pipe 135 to a temperature range of, for example, -1°C to +100°C, and supplies it to the heating and cooling plate 134 of the test unit. The heating and cooling plate 134 has a sufficiently large heat capacity.

In the above embodiment, a heating/cooling plate 134 is used, but the heating plate and cooling plate may be separate, and heating and cooling may be performed using a heat source and a cold source other than the heating/cooling plate.

Figure 11 is a configuration diagram of a semiconductor device testing device (for example, a power cycle testing device for testing power transistors) in a first embodiment of the present invention. Also, Figure 29 is an equivalent circuit diagram or explanatory diagram of the semiconductor device testing device.

The power supply device 132 has a current power supply circuit 121 and a switch circuit 122. The current power supply circuit 121 outputs a large constant current Id for testing the transistor 117. The current power supply circuit 121 supplies power (current, voltage) in synchronization with a control signal from the control circuit board 111 (controller 111), and uses the supplied power to drive the load at a set constant current or constant voltage. The current power supply circuit 121 can also set a maximum voltage value to be output.

The switch circuit 122 (SWa) turns on (supply) and off (cut) the supply of the constant current output by the current power supply circuit 121. The switch circuit 122 is set or controlled to be on (output constant current) or off (cut off constant current) based on a signal from the control circuit board (controller) 111. Typically, the switch circuit 122 is turned on before the start of testing, and is constantly maintained in the on state during testing of the semiconductor elements.

In FIG. 11, one current power supply circuit 121 is shown. The number of current power supply circuits 121 is not limited to one. For example, the semiconductor element testing apparatus of the present invention may have two or more current power supply circuits 121. The more current power supply circuits 121 are used, the more diverse the current waveforms Id that can be generated.

In the embodiment of the present invention, the power supply device 132 is described as having a current power supply circuit 121 that outputs a current, but the current power supply circuit 121 is not limited to one that outputs a constant current.

For example, a current power supply circuit 121 capable of setting a maximum voltage is used. An example is a circuit that functions to output a predetermined constant current at a set maximum voltage under certain conditions. Another example is a circuit that is configured to set the output terminal voltage to a predetermined maximum voltage when a constant current is output. It goes without saying that in the semiconductor element testing device of the present invention, the current power supply circuit 121 need not be a device that outputs only a constant current, but may be a power supply device that can output both voltage and current.

In the embodiment of FIG. 11 etc., the current Id is generated by the current power supply circuit 121, but the current Id can also be realized by adjusting the applied voltage according to the on-resistance state of the transistor 117. Therefore, it goes without saying that the semiconductor element testing device of the present invention is not limited to the current power supply circuit 121 that outputs a current, and may be configured as a power supply device that outputs a voltage.

The current Id can also be achieved by controlling the voltage value of the gate voltage of transistor 117. In this specification, a predetermined current is applied to transistor 117 by controlling the current power supply circuit 121. However, this is not limited to this, and it goes without saying that the voltage of the gate terminal g of transistor 117 and the voltage of the collector terminal c of transistor 117 may also be adjusted or controlled.

In the embodiment of the first semiconductor element testing method of the present invention, for ease of explanation, it is assumed that the constant current Id is generated by the current power supply circuit 121. The current Id flowing through the transistor 117 is supplied by operating the current power supply circuit 121. The current power supply circuit 121 is controlled to be turned on/off by a signal from the control circuit board (controller) 111. The device control circuit board 209 is timing controlled by the control circuit board (controller) 111.

The emitter terminal e of the transistor 117 is grounded (connected to the ground line). The gate terminal g of the transistor 117 is connected to the gate driver circuit 113.

The gate driver circuit 113, the variable resistance circuit 125, the constant current circuit 118, and the operational amplifier (buffer circuit) 116 are arranged or formed within the sample connection circuit 203. The sample connection circuit 203 is arranged separately from the device control circuit board 209 so that it can be arranged in a position close to the transistor 117 to be tested.

It is preferable to provide one sample connection circuit 203 for each transistor 117 to be tested, but this is not limited thereto, and one sample connection circuit 203 including multiple signal circuits may be provided for multiple transistors 117.

The sample connection circuit 203 is connected to the transistor 117 by the connection pin 206 of the connector 202. The gate driver circuit 113 and the gate terminal g of the transistor 117 are arranged so that the distance between them is short, less than 30 mm. If the distance between the gate driver circuit 113 and the gate terminal g of the transistor 117 is long, noise and the like will be superimposed on the gate terminal g, causing the transistor 117 to malfunction and directly leading to the destruction of the transistor 117.

As shown in FIG. 9, the device control circuit board 209 is placed in room B of the housing 210 of the semiconductor device testing device. The housing 210 is a frame or device body in which the power supply device 132, drive circuit, and heating/cooling plate 134 of the semiconductor device testing device are incorporated. The sample connection circuit 203 is placed in room C1 of the housing 210 of the semiconductor device testing device in order to be located close to the transistor 117 to be tested. The sample connection circuit 203 is connected to a connector 208 located on the side of the housing 210. The wiring connected to the connection pin 206 of the connector 208 is connected to the device control circuit board 209 in room B.

The housing 210 need not necessarily be box-shaped, but may also be, for example, a room. The image is of the current power supply circuit 121 being placed inside the room. Partitions 214, 215, and 217 may be the walls of the room.

9, a semiconductor element 117 (transistor, etc.) to be tested is placed in chamber C1. The transistor 117, etc. are placed and fixed in close contact with the heating and cooling plate 134.
If necessary, as shown in FIG. 15, the transistor 117 and the like are sandwiched and fixed between a heating/cooling plate 134a and a heating/cooling plate 134b.

As described above, in the present invention, the housing 210 is divided into multiple regions, such as the C1 chamber. The C1 chamber is configured to be injected with dry air (dry gas, gas with a low dew point temperature). Air pressure is applied to the C1 chamber, and the air injected into the C1 chamber is discharged through the opening 216, etc.

As shown in Figures 1 and 9, the connection structure 218 is inserted from the C2 chamber through the opening 216 of the partition wall 217. By inserting the connection structure 218, an electrical connection is established between the element terminal 226 of the transistor 117 and the connection structure 218, allowing a constant current (test current) Id to be applied to the transistor 117. As shown in Figures 23 and 24, the connection structure 218 is placed in a groove in the support base 323 and inserted into the element terminal 226 of the transistor 117. By inserting the connection structure 218, an electrical connection is established between the element terminal 226 of the transistor 117 and the connection structure 218.

The partition wall 217 has a function of electrostatic shielding and holding the connection structure 218. It goes without saying that the partition wall 217 can be omitted when a separate electrostatic shielding functional component, a fixing or holding stand for the connection structure 218 is disposed or configured.
Furthermore, it goes without saying that when the partition wall 217 is not provided, the element terminal 226 of the transistor 117 may be positioned and fixed to the connection structure 218 .

The partitions (partitions 214, 215, 217) have the function of separating each chamber (chamber C1, chamber C2, chamber A, chamber B) and the function of preventing outside air from flowing in. In particular, dry air is flowed into chamber C1 because condensation may occur during testing at low temperatures. The dry air that flows into chamber C1 is exhausted to the other chambers through opening 216. However, if the opening of opening 216 is large, a large amount of dry air is required. Therefore, it is preferable that opening 216 is sized so that fork plug 205 and connection structure 218, which serve as connection members, can be inserted.

A fixing screw 221 is attached to the other end of the connection structure 218, and the connection wiring 211 is connected to the connection structure 218. A fork plug 205 is attached to the other end of the connection wiring 211 as a connection member.
The connection structure 218 is made of copper or a copper alloy and has a silver or nickel plated surface.

The fixing screw 221 is not limited to a screw, and may be any type that can electrically connect the connection wiring 211 to the connection structure 218. It goes without saying that the fixing screw 221 may be a type that can make contact by pressing with a spring (not shown).

The sample connection circuit 203 is connected to a device control circuit board 209 by a connection pin 206 of a connector 208. The sample connection circuits 203 are individually arranged corresponding to each transistor 117 to be tested, and the sample connection circuits 203 are configured so as to be easily removable.
The connectors 208 and 213 are not limited to connectors, and may be any connectors that can electrically connect and disconnect wiring.

Figure 3 is an explanatory diagram of a connection structure 218 in the semiconductor element testing device of the present invention. Figure 3(a) is a schematic diagram of the back surface, and Figure 3(b) is a schematic diagram of the side surface.

The heat pipe 223 is in intimate contact with the recess 234 on the surface of the connection structure 218. Thermally conductive grease or a heat dissipating silicone oil compound may be applied between the surface of the connection structure 218 and the heat pipe.

The connection structure 218 of the present invention has a heat pipe 223 disposed on the side of the connection metal part 233. It is preferable that the heat pipe metal part 231 and the connection metal part 233 are integrated. The connection metal part 233 and the element terminal 226 are in electrical contact with each other, and a test current is supplied to the semiconductor element 117, etc.

The connecting fitting 232 comes into contact with the element terminal 226, and holds the element terminal 226 between the connecting fitting portion 233 and the connecting fitting 232. The connecting fitting 232 is not required to be a conductive material such as metal. It is preferable to configure the connecting fitting 232 so that the test current does not flow to the side of the connecting fitting 232.

The connection structure 218 of the present invention has a recess 234 formed therein, and the heat pipe 223 is fitted into the recess 234. A material is used for the heat pipe fitting 231 of the connection structure 218, the linear expansion coefficient of which is smaller than that of the heat pipe 223.

The connection portion of the connection structure 218 with the element terminal 226 generates heat, and the connection structure 218 heats up. Therefore, the heat pipe 223 and the heat pipe metal fitting 231 are heated. The heating causes the heat pipe 223 and the heat pipe metal fitting 231 to expand.

In the present invention, a material having a linear expansion coefficient smaller than that of the heat pipe 223 pipe for the heat pipe fitting 231 of the connection structure 218 is used, or a material having a linear expansion coefficient larger than that of the heat pipe fitting 231 is used for the heat pipe 223 pipe of the connection structure 218. The material of the heat pipe 223 expands more in the recess 234, and the heat pipe 223 is more firmly fitted into the recess 234. Therefore, the heat pipe 223 will not come off.

Examples of materials for the heat pipe fittings 231 include copper (linear expansion coefficient 16.8), brass (linear expansion coefficient 19), iron (linear expansion coefficient 12.1), and stainless steel (SUS304) (linear expansion coefficient 17.3). Examples of materials for the heat pipes 223 include materials with a linear expansion coefficient greater than that of the heat pipe fittings 231, such as aluminum (linear expansion coefficient 23), tin (linear expansion coefficient 26.9), and lead (linear expansion coefficient 29.1). Of these, it is preferable to use copper (linear expansion coefficient 16.8) for the material of the heat pipe fittings 231 and aluminum (linear expansion coefficient 23) for the material of the heat pipes 223.

The rate at which length changes in response to an increase in temperature is called the linear expansion coefficient. Similarly, the rate at which volume changes is called the volumetric expansion coefficient. If the linear expansion coefficient is α and the volumetric expansion coefficient is β, then there is a relationship of β ≒ 3α. The thermal expansion coefficient indicates the rate at which an object's length and volume expand (thermal expansion) due to an increase in temperature, per unit of temperature. It is also called the thermal expansion coefficient.

In the present invention, it is preferable that the linear expansion coefficient of the heat pipe fitting 231 of the connection structure 218 is smaller than that of the heat pipe 223 pipe, or that the linear expansion coefficient of the heat pipe 223 of the connection structure 218 is larger than that of the heat pipe fitting 231. However, it goes without saying that the linear expansion coefficient may be replaced with the thermal expansion coefficient or the volumetric expansion coefficient.

The recess 234 is formed in the heat pipe fitting 231. The heat pipe 223 is arranged so as to fit into the recess 234. By arranging the heat pipe 223 in the recess, the risk of damage to the heat pipe 223 is reduced.

The heat pipe fitting 231 is made of a metal that has good electrical and thermal conductivity. Examples of metals include copper and silver. Other non-metallic materials such as carbon can also be used.

It is preferable to use thermally conductive grease that contains boron nitride (boron). It is preferable to use heat dissipating silicone oil compound that uses silicone oil as a base oil and mixes powder with good thermal conductivity such as alumina.
The heat pipe 223 is a sealed container in which a small amount of liquid (working liquid) is vacuum sealed, and which has a capillary structure (wick) on the inner wall.

When part of the heat pipe is heated, the working fluid evaporates in the heated area (absorbing the latent heat of evaporation), and the vapor moves to the low-temperature area at high speed (the speed of sound). The vapor condenses in the low-temperature area (releasing the latent heat of evaporation), and the condensed working fluid flows back to the heated area due to the capillary action of the wick. The above phase changes are repeated continuously without any external force, and heat is transferred instantly, allowing the heat generated at the terminals of the semiconductor element to be transferred quickly and efficiently.

The heat pipe 223 is composed of an array of multiple containers (copper pipes). The inside of the container is in a highly decompressed state, and contains a wick (capillary structure) and an appropriate amount of working fluid (pure water, etc.).
As the working fluid, in addition to pure water, methanol (methyl alcohol), acetone, sodium, mercury, a fluorocarbon-based refrigerant, or ammonia may be used.
Wick materials include aluminum, copper, stainless steel, sintered alloy, wire mesh, foamed metal, ceramics, and the like.

The connection structure 218 is not limited to metal. It goes without saying that it may be made of a nonmetallic material such as ceramic, graphite, or a composite material of graphite and copper or aluminum. In the case where a current is passed directly through the connection structure 218, the connection structure 218 is made of a metallic material such as copper. It is preferable that the surface of the connection structure 218 is plated with silver, nickel, or the like.

As shown in FIG. 3, the connection structure 218 mainly consists of a heat pipe fitting 231, a connection fitting 232, and a connection fitting portion 233. The element terminal 226 of the semiconductor element is inserted between the connection fitting 232 and the connection fitting portion 233.

Figure 12 is an explanatory diagram of a semiconductor element 117 to be tested. A transistor is shown as an example of the semiconductor element 117. The transistor 117 has a P terminal (collector terminal of the transistor 117) to which a large current is applied, and an N terminal (emitter terminal of the transistor 117) to which a large current is applied. A diode Di is formed or added between the emitter terminal and the collector terminal. A test current Id is applied to the P terminal and the N terminal.

Transistor 117 has a collector terminal c, a gate terminal g, and an emitter terminal e. A signal Vgs that turns transistor 117 on and off is applied to gate terminal g. A constant current Ic is passed from constant current circuit 118 to diode Di between emitter terminal e and collector terminal c.

Contact parts 225a and 225b are disposed between the connecting fitting 232 and the connecting fitting part 233. Platinum, gold, silver, tungsten, copper, nickel, or an alloy of a combination of these is used as the contact part 225. It is also preferable to use a silver-oxide contact material (Ag+ZnO, Ag+SnO ₂ , Ag+SnO ₂ In ₂ O ₃ , Ag+, Ag+SnO ₂ Sn ₂ Bi ₂ O ₇ ).

As an example, the connection fitting portion 233 is integrated with the heat pipe fitting 231. The connection fitting 232 is fixed to the connection fitting portion 233 with a fixing screw 224b. The element terminal 226 of the semiconductor element is fixed by tightening the fixing screw 224b. The connection wiring 211 is fixed to the left end of the heat pipe fitting 231 with a fixing screw 221.

Figure 15 is an explanatory diagram of the state in which the element terminal 226 is connected to the connection structure 218. The element terminal 226 is sandwiched between the contact portion 225a and the contact portion 225b. The connection fitting 232 is fixed to the element terminal 226 by the fixing screw 224b.

The transistor 117 is fixed to the heating and cooling plate 134a and is further sandwiched between the heating and cooling plate 134b. The transistor 117 is appropriately maintained at the test temperature by the heating and cooling plate 134. A heat pipe 223 is attached in the recess 234.

A test constant current Id is applied from the connection structure 218 to the element terminal 226. The constant current Id is large, at several hundred amperes (A). The element terminal 226 is small, and there is contact resistance between the contact portion 225 and the element terminal 226. Therefore, when a large current flows through the element terminal 226, heat is generated at the contact portion 225.

The heat is conducted to the transistor 117 being tested, causing it to overheat. Overheating can cause the transistor 117 to deteriorate or the element terminal 226 to burn out. Therefore, it is necessary to dissipate the heat generated at the contact portion 225 as quickly as possible.

The connection structure 218 of the present invention has a heat pipe 223. The heat generated at the contact portion 225 is transferred by the heat pipe 223. Therefore, the heat at the contact portion 225 is quickly removed from the contact portion 225.

A partition wall 217 is disposed between the C1 and C2 chambers. As shown in FIG. 14, an opening 216 is formed in the partition wall 217. A connection structure 218a1 is inserted into the opening 216a1, and a connection structure 218b1 is inserted into the opening 216b1. A connection structure 218a2 is inserted into the opening 216a2, and a connection structure 218b2 is inserted into the opening 216b2. A connection structure 218an is inserted into the opening 216an, and a connection structure 218bn is inserted into the opening 216bn.

For example, in the semiconductor element testing device of FIG. 36, the P terminal of the transistor 117Q1 to be tested is clamped and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218a1. Also, the N terminal of the transistor 117Q1 to be tested is clamped and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218b1.

Similarly, the P terminal of the transistor 117Q2 to be tested is sandwiched and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218a2. Also, the N terminal of the transistor 117Q2 to be tested is sandwiched and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218b2.

Similarly, the P terminal of the transistor 117Qn to be tested is sandwiched and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218an. Also, the N terminal of the transistor 117Qn to be tested is sandwiched and electrically connected between the connection fitting 232 and the connection fitting portion 233 of the connection structure 218bn.

An electromagnetic shield plate, electrostatic shield plate, or electromagnetic shield mesh, electrostatic shield mesh, etc. is arranged on the partition 217, blocking noise from the power supply unit 132 and the drive circuit system of chamber B, and the noise is not applied to chamber C1. In addition, noise generated by turning on and off the transistor 117 is not applied to the drive circuit system of chamber B.

Figure 1 is an explanatory diagram explaining the connection state between the transistor 117 and the connection structure 218. The transistor 117 is fixed in close contact with the heating and cooling plate 134a. The fixing is performed by a spring (not shown). The adhesion may be achieved by applying thermally conductive grease or a silicone oil compound for heat dissipation. If necessary, as shown in Figure 15, a heating and cooling plate 134b is also placed above the transistor 117 so that the transistor 117 can be set to a predetermined temperature condition.

A connector 202 is connected to the terminals (emitter terminal e, gate terminal g, collector terminal c) of the transistor 117. A signal wiring 222 is drawn out to the connector 202. A control signal Vgs to be applied to the gate terminal g of the transistor 117 and a constant current Ic from the constant current circuit 118 are applied to the signal wiring 222.

The connection structure 218a is inserted into the opening 216a of the partition 217 from the C2 chamber side. Similarly, the connection structure 218b is inserted into the opening 216b of the partition 217 from the C2 chamber side. When the connection structure 218 is inserted, the element terminal 226 is sandwiched between the connection fitting 232 and the connection fitting portion 233. In this state, the element terminal 226 of the transistor 117 and the connection structure 218 are electrically connected by tightening the fixing screw 224b.

The transistors 117 to be tested must be fixed in close contact with the heating and cooling plate 134, and so are difficult to remove easily. The transistors 117 are attached by first fixing the multiple transistors 117 to be tested to the heating and cooling plate 134. Next, the transistor 117 to be tested first is selected and the connection structure 218 is attached to the element terminal 226.

The selected transistor 117 is electrically connected to the element terminal 226 by inserting the connection structure 218 from the C2 chamber side into the opening 216 in which the selected transistor 117 is located.

Electrical connection with the transistor 117 is easy since it is only necessary to select the position where the connection structure 218 is inserted. In addition, the test conditions and test contents of the transistor 117 can be easily changed by changing the signal applied to the connection wiring 211 connected to the connection structure 218.

The element terminal 226 is clamped by applying pressure between the contact portion 225a and the contact portion 225b. The connection wiring 211 is connected to one end of the connection structure 218, and a constant current Id is applied from the connection wiring 211 to the transistor 117. A heat pipe 223 is disposed on the back side of the connection structure 218.

A current of several hundred amperes (A) flows through the element terminal 226. Even if there is a small resistance at the contact portion 225, a current of several hundred amperes (A) generates a large amount of heat, overheating the element terminal 226. If this occurs, the transistor 117 will also overheat, causing the transistor 117 to deteriorate or break down.

In the present invention, heat generated at the contact portion 225 is transferred to the connection wiring 211 side of the connection structure 218 by the heat pipe 223. Therefore, the contact portion 225 does not overheat. A cooling fan 227 is disposed below the connection structure 218 to dissipate heat from the heat pipe 223.
FIG. 2 is an explanatory diagram for explaining a method of connecting a semiconductor element 117 and a connection structure 218 in the semiconductor testing device of the present invention.

A partition 217 is provided between the C1 and C2 chambers. As shown in FIG. 14, an opening 216 is formed in the partition 217 corresponding to the position of the transistor 117 to be tested. The opening 216 in the partition 217 and a fixing base (not shown) for the connection structure 218 position and fix the connection structure 218 horizontally or stably.

As shown in FIG. 2(a), the transistor 117 to be tested is positioned and fixed in place by being in close contact with the heating and cooling plate 134a. Thermally conductive grease and silicone oil compound for heat dissipation are applied between the transistor 117 and the heating and cooling plate 134a.

A detachable connector 202 is connected to the terminals (emitter terminal e, gate terminal g, collector terminal c) of the transistor 117. A signal wiring 222 is connected to the connector 202, and the signal wiring 222 is connected to the sample connection circuit 203.

The signal wiring 222 between the sample connection circuit 203 and the connector 202 is formed to be as short as possible. If the signal wiring 222 is long, noise will be superimposed on the signal wiring 222, causing the transistor 117 to malfunction. For example, if noise is superimposed on the gate terminal g of the transistor 117, the transistor 117 will turn on, which may destroy the transistor 117. The signal wiring 222 should be twisted wiring, or a shielded wiring such as a coaxial cable should be used.

As shown in FIG. 9, the connector 208 is provided on the side of the housing 210, and the connector 208 and the device control circuit board 209 arranged in the B room are connected by a signal wiring 235. The device control circuit board 209 inputs and outputs control signals or output signals of the gate driver circuit 113, the gate signal control circuit 112, the temperature measurement circuit 115, the variable resistance circuit 125, and the operational amplifier circuit 116.

As shown in FIG. 2(b), the connection structure 218a is inserted into the opening 216a. When the connection structure 218a is inserted into the opening 216a, the element terminal 226a of the transistor 117 is sandwiched between the connection fitting 232 at the tip of the connection structure 218a and the connection fitting portion 233. After the connection structure 218a and the element terminal 226a are connected, the fixing screw 224b1 is tightened to achieve good electrical connection between the contact portion 225 and the element terminal 226.

Similarly, the connection structure 218b is inserted into the opening 216b. By inserting the connection structure 218b into the opening 216b, the element terminal 226b of the transistor 117 is sandwiched between the connection fitting 232 at the tip of the connection structure 218b and the connection fitting portion 233. After the connection structure 218b and the element terminal 226b are connected, the fixing screw 224b2 is tightened to achieve a good electrical connection between the contact portion 225 and the element terminal 226.

A cooling fan 227 for removing heat from the heat pipe 223 is arranged on the back surface of the connection structure 218. The rotation speed of the cooling fan 227 is controlled according to the overheating state of the element terminal 226 and the heat pipe 223.

In the embodiment shown in FIG. 3, the heat pipe 223 is attached to the recess 234 of the heat pipe fitting 231 of the connection structure 218. However, the present invention is not limited to this.

For example, the connection structure 218 may be configured as shown in FIG. 4. In FIG. 4, FIG. 4(a) is a schematic illustration of the back surface (lower surface) of the connection structure 218, and FIG. 4(b) is a schematic illustration of the front surface (upper surface) of the connection structure 218.

In FIG. 4, the heat pipe 223a is disposed on the concave surface 234a. The heat pipe 223a is formed or disposed up to the connecting metal fitting portion 233. By forming or disposing the heat pipe 223a up to the connecting metal fitting portion 233, the heat generated by the element terminal 226 can be transferred more efficiently.

As shown in FIG. 4B, the heat pipe 223b is disposed on the concave surface 234b. By disposing the heat pipe 223 on both sides of the connection structure 218, the heat generated by the element terminal 226 can be transferred more efficiently.

In the embodiment of FIG. 3, the heat pipe 223 and the like are cooled by the cooling fan 227, but the present invention is not limited to this. For example, as shown in FIG. 5, the heat dissipation fins 228 may be formed or arranged so as to be in close contact with the heat pipe 223. The heat transferred within the heat pipe 223 is efficiently transferred to the heat dissipation fins 228, and the heat transfer and heat dissipation effect of the heat pipe 223 is further improved.

The heat dissipation fins 228 in FIG. 5 are not formed or placed in the area corresponding to the opening 216. The connection structure 218 is inserted from the C2 chamber to the C1 chamber side through the opening 216. In order to maintain the airtightness of the C1 chamber, the opening 216 has a size equal to the cross-sectional area of the connection structure 218 + α. Therefore, if the heat dissipation fins 228 are formed or placed on the connection structure 218, they cannot be inserted into the opening 216. Therefore, the heat dissipation fins 228 are not formed or placed on the side connected to the element terminal 226 of the transistor 117 with respect to the partition wall 217.

Also, as shown in FIG. 6, a circulating water pipe 135 may be formed or disposed within the connection structure 218 to cool the connection structure 218. The connection structure 218 is cooled by the refrigerant flowing through the circulating water pipe, and the heat transfer within the heat pipe 223 is efficiently transferred to the connection structure 218. Therefore, the heat generated at the element terminal 226 is efficiently dissipated.

The transistor 117 (semiconductor element 117) in FIG. 12 has two element terminals 226, element terminal 226a (P) and element terminal 226b (N). However, as shown in FIG. 13, there are also transistors 117 whose element terminals 226 have three terminals, element terminal 226a (P), element terminal 226b (N), and element terminal 226c. The semiconductor element testing apparatus and semiconductor element testing method of the present invention can test a wide variety of semiconductor elements 117.

The semiconductor element 117 in FIG. 13 has two transistors, transistor 117m and transistor 117s, arranged in one package. The collector terminal c of transistor 117s is connected to element terminal 226a. The emitter terminal e of transistor 117s and the collector terminal c of transistor 117m are connected, with the midpoint connected to element terminal 226c. The emitter terminal e of transistor 117m is connected to element terminal 226b.

Transistor 117m is connected to emitter terminal e1, gate terminal g1, and collector terminal c1. Transistor 117s is connected to emitter terminal e2, gate terminal g2, and collector terminal c2.

Figure 7 is an explanatory diagram illustrating the connection state between a transistor 117 (semiconductor element 117) having three element terminals 226 (element terminal 226a (P), element terminal 226b (N), element terminal 226c (O)) and a connection structure 218.

In FIG. 7, the connection between the connection structure 218a and the element terminal 226a, and the connection between the connection structure 218b and the element terminal 226b are the same as those described in FIG. 1 and FIG. 2, so the description is omitted.

7, the heat pipe 223a is formed or arranged in the connection structure 218a, and the heat pipe 223b is formed or arranged in the connection structure 218b, whereas the heat pipe 223 is not formed or arranged in the connection structure 218c. The connection structure 218c is connected to the element terminal 226c. A large current does not flow through the element terminal 226c (O) of the transistor 117. Therefore, the element terminal 226c does not overheat. There is no need to form the heat pipe 223 in the connection structure 218c. By forming the connection structure 218c thinner than the other connection structures 218 (connection structures 218a, connection structures 218b), it becomes easier to connect the connection structure 218 and the element terminal 226 of the transistor 117. In addition, since the space for arranging the transistor 117 may be narrow, the number of transistors 117 that can be mounted on the heating/cooling plate 134 can be increased.

It goes without saying that a heat pipe 223 may be formed or disposed in the connection structure 218c. Other details are the same as or similar to the embodiment shown in Figures 1 and 2, so a description thereof will be omitted.

15, the element terminal 226 is sandwiched between the contact portions 225a and 225b to establish an electrical connection. The current supplied to the element terminal 226 of the transistor 117 mainly flows through the connecting metal part 233, but some current flows from the connecting metal part 232 to the element terminal 226.
The current flowing through the connecting fitting 232 flows in the following order: fixing screw 224 b , connecting fitting 232 , contact portion 225 b , and element terminal 226 .
The current flowing through the element terminal 226 can be as large as several hundred amperes, and if the connection resistance is high at the fixing screw 224b or the like, heat will be generated and the heat generating portion will burn out.

Although the present specification and drawings depict a metal fitting having electrical conductivity, such as the metal fitting 232, the metal fitting 232 is not required to be made of a conductive metal. It goes without saying that the metal fitting 232 may be made of a resin material or the like.
FIG. 16 is an explanatory diagram illustrating a method and structure for connecting a connection structure 218 and an element terminal 226 in another embodiment of the present invention.

The element terminal 226 is sandwiched between the pressing tool mounting plate 313 and the connection metal part 233. Pressing tools 311a and 311b are attached to the pressing tool mounting plate 313. The pressing tool 311 is, for example, a leaf spring made of metal. The pressing tool 311 may be made of a non-conductive material such as a silicone resin material. The pressing tool 311 is fitted into the pressing tool mounting plate 313. It is preferable that the surface of the pressing tool 311 is roughened so that it can press the element terminal 226 appropriately.

The element terminal 226 is clamped between the flat surfaces of the pressing tool 311 and the connecting fitting portion 233. By pressing the pressing tool 311, the element terminal 226 and the connecting fitting portion 233 are electrically connected. The pressing tool 311 is not required to be conductive.

It is preferable that the connection metal part 233 is configured as one piece with the heat pipe metal part 231. The connection metal part 232 is fixed to the connection metal part 233 with a fixing screw 224b. The element terminal 226 of the semiconductor element is fixed by tightening or positioning the fixing screw 224b. The connection wiring 211 is fixed to the left end of the heat pipe metal part 231 with a fixing screw 221.
The connecting fitting portion 233 is connected and fixed to the connecting fitting 232 by screws 224b inserted into the screw holes 238b1 and 238b2.

The screw 224 may be made of a metal material such as phosphor bronze or stainless steel, but is not limited to these. It may also be made of a non-conductive material such as a resin material. Alternatively, it may be made of a cushioning material such as a sponge.

The pressing tool mounting plate 313 has convex portions 251 formed on both ends, and the connecting fitting 232 has groove portions 252 formed on both ends. The convex portions 251 of the pressing tool mounting plate 313 are fitted into the groove portions 252 of the connecting fitting 232. The convex portions 251 of the pressing tool mounting plate 313 and the groove portions 252 of the connecting fitting 232 are configured to be in electrical contact.

Figure 18 is an explanatory diagram and diagram of the pressure mounting plate 313 in Figure 16. Figure 18 (a) is a side view of the pressure mounting plate 313, and Figure 18 (b) is a bottom view of the pressure mounting plate 313 seen from the back side.

As shown in FIG. 18(b), a plurality of pressing tools 311a and a plurality of pressing tools 311b are arranged in a matrix on the back surface of the pressure mounting plate 313. Also, as shown in FIG. 18(a), the pressing tool 311 is fitted into the pressure mounting plate 313.

Positioning screw holes 240 are formed in the pressure mounting plate 313, and positioning fixing screws 237 are inserted into the positioning screw holes 240. In addition, spring holes 239 are formed in the pressure mounting plate 313, and springs 236 are inserted into the spring holes 239. In the embodiment of Fig. 16, the appropriate pressure is applied between the pressing tool 311 and the element terminals 226 by the springs (pressure fittings) 236, and good electrical connection is maintained.

In the embodiment of FIG. 16, the spring (pressure fitting) 236 is inserted into the spring hole 239 of the contact portion 225. If the spring (pressure fitting) 236, the contact portion 225, and the connection fitting 232 are made of conductive materials, electricity may flow from the element terminal 226 -> contact portion 225 -> spring (pressure fitting) 236 -> connection fitting 232. In this case, if the resistance value of the spring (pressure fitting) 236 is high, current may flow through the spring (pressure fitting) 236, causing the spring to heat up and burn out.

If the pressure tool 311 is made of a non-conductive material and configured so that no current flows through the pressure tool mounting plate 313, the aforementioned current path will not occur and the spring (pressure fitting) 236 will not burn out.

Figure 17 is an explanatory diagram and diagram of a connection structure 218 in another embodiment of the present invention. In the embodiment of the present invention in Figure 17, a spring hole 312 is formed in an insulating plate 312. A pressing tool 311 contacts an element terminal 226, and a spring 236 presses a pressing tool mounting plate 313. An insulating plate 312 is disposed above the pressing tool mounting plate 313, providing insulation between the pressing tool mounting plate 313 and the spring 236. A spring hole 239 is formed in the insulating plate 312, and a spring 236 is inserted into the spring hole 239.

As shown in FIG. 17, the pressing tool 311 contacts the element terminal 226, and the spring 236 presses the pressing tool mounting plate 313. An insulating plate 312 is disposed above the pressing tool mounting plate 313, providing insulation between the pressing tool mounting plate 313 and the spring 236. A spring hole 239 is formed in the insulating plate 312, and the spring 236 is inserted into the spring hole 239. The other configuration is the same as in FIG. 16, so a description is omitted.

Figure 19 is an explanatory diagram of the pressing tool mounting plate 313 and insulating plate 312 of the connection structure 218 in Figure 17. Figure 19(a) is a side view of the pressing tool mounting plate 313. Figure 19(b) is a side view of the pressing tool mounting plate 313 as viewed from side A in Figure 19(a).

Pressing tool 311a and pressing tool 311b are arranged and inserted into pressing tool mounting plate 313. In the embodiment of FIG. 19, insulating plate 312 and protruding portion 251 are made of an insulating material, and spring hole 312 is formed in insulating plate 312. Therefore, since spring hole 312 is insulated, no current path is generated in connecting fitting 232.

Since the insulating plate 312 is made of an insulating material, even if the pressing tool attachment plate 313 is made of a conductive material such as metal, no current flows through the spring (pressure fitting) 236. Therefore, a current path from the element terminal 226 to the contact portion 225 to the spring (pressure fitting) 236 to the connecting fitting 232 is not generated.
The insulating plate 312 may be an insulating film, an insulating film, or an insulating gas such as air, etc. The pressing tool attachment plate 313 may be made of a non-conductive material.

The embodiment in FIG. 17 is configured to insulate using an insulating plate 312. The insulating effect of the present invention is not limited to the configuration using an insulating plate 312 as in FIG. 17. For example, the configuration shown in FIG. 20 is an example.

Figure 20 shows a configuration in which an insulating section 315 made of a resin material or the like is arranged around the screw hole 238b of the connecting fitting 232. Figure 22 is a configuration diagram of the connecting fitting 232 of Figure 20 viewed from the back. As shown in Figure 22, the periphery of the screw hole 238b is surrounded by the insulating section 315, so that the screw can be insulated. Note that a fixing screw 224b made of an insulating material may also be used.

No current flows through the fixing screw 224b because the periphery of the screw hole 238b is insulated by the insulating portion 315. Therefore, no current path is generated from the element terminal 226 to the contact portion 225 to the spring (pressure fitting) 236 to the connecting fitting 232, and the spring (pressure fitting) 236 is not burned.
As described above, the present invention is configured such that insulating plate 312 is disposed on the side of spring 236 that applies pressure, so that current does not flow to pressure tool attachment plate 313 and contact portion 225 .

When a current flows, it flows through the pressing parts such as the spring 236 and the fixing screw 224b, causing the spring 236 and the fixing screw 224b to burn out. The current is supplied to the element terminal 226 via the connecting metal part 233 side, which has fewer electrically high resistance parts such as the spring 236.

Figures 16, 17, and 20 show examples of a connection structure 218 having a pressing tool 311. The present invention is not limited to this, and may have the configuration shown in Figure 21, for example.

Figure 21 shows a configuration in which the element terminal 226 is clamped between the contact portion 225 and the connecting fitting portion 233. By roughening the surface of the contact portion 225, pressure can be applied uniformly to the element terminal 226. By constructing the contact portion 225 from an insulating material, it is possible to prevent a current path from occurring in the connecting fitting 232.

It goes without saying that preventing a current path from occurring on the connection fitting 232 side can also be achieved by constructing the fixing screw 224b and the connection fitting 232 from an insulating material.

In the electrical element testing device of the present invention, as illustrated and explained in Figures 1 and 14, one end of the connection structure 218 is connected to the element terminal 226 of the semiconductor element 117 by inserting the connection structure 218 into the opening 216. The present invention is not limited to this. For example, the configurations illustrated in Figures 23 and 24 are exemplified.

Figure 23 is an explanatory diagram of the connection structure 218 of the electrical element test device of the present invention, viewed from the front. Figure 24 is an explanatory diagram of the connection structure 218 of the electrical element test device of the present invention, viewed from above. A cooling fan 227 is disposed on the side, and the fan cools the heat pipe 223 of the connection structure 218.

23 illustrates the heater/cooler 322 with the top side facing the paper and the bottom side facing the paper. As an example, the heater/cooler 322 has two electric element insertion holes 324, and the electric element 117 is inserted into the electric element insertion holes 324 in close contact with the heater/cooler 322.
A connection structure 218a is connected to an element terminal 226a of the electric element 117, and a connection structure 218b is connected to an element terminal 226b of the electric element 117.

A circulating water pipe 135 is attached to the heater/cooler 322, and circulating water flows in through the circulating water pipe 135a, circulates through the heater/cooler 322, and is discharged from the circulating water pipe 135b. The circulating water maintains the electric element 117 at a predetermined temperature.

The connection structure 218 is placed in the slide groove 325 of the support base 323, and the connection structure 218 is slid along the slide groove 325 so that the connection fitting 232 and the connection fitting portion 233 of the connection structure 218 are electrically connected to the element terminal 226.

Figure 25 illustrates the fork plug 205 and the connection (contact) state between the fork plug 205 and the conductor plate 204. Two conductor plates 204 are attached to the switch circuit board 201. The switch circuit board 201 has a full earth layer (not shown), and the full earth layer and the conductor plate 204 are thermally connected. Heat from the conductor plate 204 is dissipated via the full earth layer. The conductor plate 204 and the switch circuit board 201 are secured with screws.

In this specification and drawings, the conductor plate 204 is described as being a plate, but it is not limited to being a plate, and may be rod-shaped. Any shape may be used as long as it can be joined to a structure such as the fork plug 205. For example, it may be a structure such as a socket or connector. Also, the conductor plate 204 may be in the shape of a fork plug, and the fork plug 205 may be connected to the fork plug.

The fork plug 205 is described as being inserted into a component or structure that separates a space, such as the bulkhead 214, but this is not limiting. For example, the fork plug 205c may be connected to the conductor plate 204b, and the fork plug 205c may be inserted through the bulkhead 214 to electrically connect to the emitter terminal e of the transistor 117.

Partitions 214 and 215 may be of any type that divides or separates spaces or regions. They may have a wide variety of configurations or structures, such as wall-like, plate-like, mesh-like, film-like, foil-like, etc.

The fork plug 205 may have any configuration, structure, form, style, or method that allows it to be electrically connected to an object such as the conductor plate 204 by press-fitting, pressure welding, insertion, crimping, clamping, fitting, or the like.

The switch circuit 124 is connected to two conductor plates. As shown in FIG. 30, if the switch circuit 124 is a MOS transistor, the drain terminal and source terminal are connected to different conductor plates 204. If the switch circuit 124 is a bipolar transistor, the collector terminal and emitter terminal are connected to different conductor plates 204. When the switch circuit 124 is turned on (conductive), the two conductor plates 204 are electrically connected. An IGBT can also be used as the switch circuit 124.

The switch circuit 124 is mounted on the switch circuit board 201. The switch circuit 124 is connected to a conductor plate 204 (metal plate, conductive plate). The conductor plate 204 is, for example, a copper plate with a thickness of 5 mm and a width of 50 mm. Its length is the width of the circuit board plus the width required to connect the fork plug 205.

The fork plug 205 and the conductor plate 204 are electrically connected by mechanically fitting them together. When the U-shaped portion of the fork plug 205 is inserted into the conductor plate 204, the U-shaped portion expands slightly, and the fork plug 205 and the conductor plate 204 are well joined. With a good joint or fit, the electrical resistance of the connection is extremely small, and no heat is generated or voltage drops occur even when a large current flows through the connection.

A connection bolt 219 is attached to the fork plug 205. A connection wiring 211 is connected to the connection bolt 219. A cross section taken along line AA' in Fig. 25(a) is shown in Fig. 25(b). The conductive plate 204 and the fork plug 205 are in contact with each other at contact parts 220a and 220b formed on the fork plug 205. The surface of the contact part 220 is silver plated. The contact part 220 is made of phosphor bronze and nickel alloy.
The connection bolt 219 is not limited to a bolt, and may be anything that can electrically connect the fork plug 205 and a wire.
At least the surface of the conductive plate 204 that comes into contact with the fork plug 205 is plated with silver.

Figure 10 is a diagram showing the configuration of a semiconductor device testing device of the present invention. A connection structure 218a is inserted into the opening 216a of the partition 217, and a connection structure 218b is inserted into the opening 216b of the partition 217.

It goes without saying that, as illustrated and explained in Figures 23 and 24, the connection structure 218 may be slid into the slide groove 325 of the support base 323 to connect to the element terminal 226 of the semiconductor element 117.

The connection structure 218a is connected to the element terminal 226a of the transistor 117, and the connection structure 218b is connected to the element terminal 226b of the transistor 117. A circulating water pipe 135 is incorporated into the heating/cooling plate 134.

A connector 202 is connected to the terminal of the transistor 117, and a signal wiring 222 connected to the connector 202 is connected to the sample connection circuit 203. The signal wiring 235 of the sample connection circuit 203 is connected to the device control circuit board 209 via the connector 208.

As shown in FIG. 10, the fork plug 205 and the conductive plate 204 are brought into contact by inserting the fork plug 205 through the opening 216 of the bulkhead 214. When the fork plug 205 comes into contact with the conductive plate 204, the U-shaped portion of the fork plug 205 is expanded by the conductive plate 204, and the fork plug 205 comes into contact with the conductive plate 204 firmly.

Figure 9 shows the layout of each component of the semiconductor device testing device of the present invention. The housing 210 of the semiconductor device testing device is separated into three parts. The lower part of the housing is separated into chamber A and chamber B. The power supply unit 132 is placed in chamber A. Chamber A and chamber B are separated by a partition wall 215.

Each chamber is shielded. The power supply 132, switch circuit board 201, and transistor 117 generate large noise as they repeatedly operate and deactivate. Noise can cause circuit boards and other components to malfunction, so shielding is used to prevent this. The shielding is achieved by placing conductive plates, metal plates, and metal films around each chamber.

In chamber C1, the heating and cooling plate 134, circulating water pipe 135, etc. shown in FIG. 8 are arranged, and the transistor 117 to be tested is placed on the heating and cooling plate 134.

Partition walls 214 are formed between chamber C1 and chambers A and B. A water leakage sensor (not shown) is arranged around the heating and cooling plate of chamber C1. If circulating water (cooling medium) or the like leaks, the water leakage sensor is activated and is configured to stop the semiconductor device testing equipment or sound an alarm.

In addition, a drainage groove is formed around the periphery of the heating and cooling plate, so that if circulating water (cooling medium) leaks from the heating and cooling plate, the circulating water (cooling medium) flows into the drainage groove and is discharged outside the semiconductor element testing equipment.
As described above, the partition wall 214 is configured so that even if the circulating water pipe 135 is damaged, the circulating water (cooling medium) and the like will not leak into the lower chambers A and B.

A partition wall 215 is formed between chamber A, in which the power supply unit 132 is located, and chamber B, in which the drive circuit system is located. Electrostatic shielding plates are placed on partition walls 214, 215, and 217 to block noise from the power supply unit 132 and prevent the noise from being applied to the drive circuit system in chamber B.

In the embodiment of the present invention, the fork plug 205 is inserted from the C2 chamber and connected to the conductive plate 204 in the B chamber. It is easy to push the fork plug 205 from the top to the bottom. However, the present invention is not limited to this. For example, the conductive plate 204 may be placed in the C2 chamber, and the fork plug 205 may be inserted from the B chamber to establish an electrical connection.
Furthermore, the connection structure 218 is inserted from the C2 chamber, and the element terminal 226 of the semiconductor element 117 and the connection structure 218 are connected.

As shown in FIG. 9 etc., the connection structure 218 is inserted from chamber C2 to chamber C1 and electrically connected to the element terminal 226 of the transistor 117. Also, the fork plug 205 is inserted from chamber C2 to chamber B and electrically connected to the fork plug 205 and the conductor plate 204. The transistor 117 is fixed to the heating and cooling plate 134, and the switch circuit board 201 is fixed at the mother board 207 position. The connection structure 218 and the fork plug 205 are electrically connected by the connection wiring 211.

The position of the opening 216 can be selected with the connection structure 218, and the transistor 117 to be tested can be selected. By selecting the opening into which the fork plug 205 is inserted, the switch circuit board 201 to be controlled can be easily selected, and the test method and test conditions can be changed. Therefore, by using the connection structure 218 and the fork plug 205, the present invention makes it easy to select the transistor 117, and to change the test method, etc., in a short time.

Note that partitions 214, 215, and 217 may be wall-shaped structures, plate-shaped structures, film-shaped objects, mesh-shaped objects, wire mesh-shaped objects, etc. One example is phenolic resin (phenolic resin, phenol-formaldehyde resin, phenolic resin). The partition may be any object that separates the first and second parts of the semiconductor device testing apparatus.

As shown in FIG. 26, a connector 213 is attached to the motherboard 207. A control circuit board 111, a device control circuit board 209, and a switch circuit board 201 are attached to the connector of the motherboard 207. The number of switch circuit boards 201 prepared according to the number of transistors 117 to be tested can be easily realized by changing the number of switch circuit boards 201 attached to the motherboard 207.

Temperature information Tj, voltage Vi, a control signal for the variable resistance circuit 125, a control signal for the constant current circuit 118, etc. are transmitted to the mother board 207. In addition, power supply wiring and ground wiring for each circuit are formed and supplied to each circuit board via a connector 213.
The conductive plate 204 is disposed so as to protrude from the switch circuit board 201. A fork plug 205 is connected to this protruding portion.

The fork plug 205a is connected to the conductor plate 204a of the switch circuit board 201a. The power supply wiring 212 is connected to the switch circuit board 201a through the opening 216 of the bulkhead 215. The fork plug 205d is connected to the conductor plate 204c of the switch circuit board 201b. The power supply wiring 212 is connected to the switch circuit board 201b through the opening 216 of the bulkhead 215. The fork plug 205b is connected to the conductor plate 204b of the switch circuit board 201a. The power supply wiring 212 is connected to the switch circuit board 201a through the opening 216 of the bulkhead 215.

As shown in FIG. 11 etc., a switch circuit 124a is disposed between conductor plate 204d and conductor plate 204c of switch circuit board 201b, and short-circuits conductor plate 204d and conductor plate 204c. By short-circuiting, the current Ia output by current power supply circuit 121a is supplied to transistor 117 as test current Id.

Switch circuit 124b is disposed between conductor plate 204a and conductor plate 204b of switch circuit board 201a, and when switch circuit 124b is turned on, conductor plate 204a and conductor plate 204b are short-circuited. When this is done, current Ia output by current power supply circuit 121a flows to ground as discharge current Im, and the channels of transistor 117 are short-circuited. When the channels are short-circuited, no overvoltage or overcurrent is applied to transistor 117.

Fork plug 205 is connected to conductor plate 204. Fork plug 205c is connected to conductor plate 204b. Fork plug 205b is connected to conductor plate 204a. Fork plug 205e is connected to conductor plate 204d. Fork plug 205d is connected to conductor plate 204c.

Figure 25 is a diagram of the configuration of the fork plug 205. Figure 25(a) shows the state in which the conductor plate 204 attached to the switch circuit board 201 and the fork plug 205 are connected. Figure 25(b) shows the connected state of the conductor plate 204 and the fork plug 205 when the cross section of line AA' in Figure 25(a) is viewed from the direction of the arrow.

The fork plug 205 is made of a metal such as aluminum. The surface is nickel-treated and then silver-plated. The fork plug 205 is threaded, and is configured so that the connection wiring 211 can be attached to the fork plug 205 with a connection bolt 219.

The convex contact portion 220 is made of phosphor bronze and copper alloy. The surface of the contact portion 220 is silver plated. The insertion force of the fork plug 205 into the conductor plate 204 is configured to be 40 to 60 N.

Platinum, gold, silver, tungsten, copper, nickel, or alloys of combinations thereof may be used for the _{contact 220.} It is also preferred to use silver-oxide contact materials ( _Ag + _ZnO , Ag+ _SnO2 , Ag+ _SnO2In2O3 , Ag+, _Ag + _SnO2Sn2Bi2O7 ).

In FIG. 26, two switch circuit boards 201 are shown, but depending on the number of transistors 117 to be tested, two or more switch circuit boards 201 may be required, and the switch circuit boards 201 are connected to the connectors 213 of the mother board 207.

As shown in Fig. 10, the fork plug 205c is inserted through an opening 216 in a partition wall 214 provided between the C2 chamber and the B chamber, and the conductor plate 204b and the fork plug 205c are connected. The transistor 117 to be tested and the heating and cooling plate 134 are arranged in the C1 chamber, and a driving circuit for testing the transistor 117 and the like are arranged in the B chamber. Since the C1 chamber, the C2 chamber, and the B chamber are separated by the partition wall 214, even if the refrigerant liquid leaks from the heating and cooling plate 134, it will not leak into the B chamber. A water leakage sensor (not shown) is arranged around the heating and cooling plate 134. In addition, a groove is formed to discharge the refrigerant liquid to the outside of the testing device if the refrigerant leaks out.
An electrostatic shield plate is disposed on the partition 214 so as to prevent the drive circuit system in the chamber B from malfunctioning due to noise generated from the transistor 117 .

The current flowing through the transistor 117 to be tested is large, at several hundred amperes, so the connection wiring 211 used is also thick. As a result, the connection wiring 211 does not slide smoothly, and is also hard, making it difficult to change the connection of the connection wiring 211.

The semiconductor element testing device of the present invention can be connected to the switch circuit board 201 by the fork plug 205 inserted from the C2 chamber. Therefore, changing the connection with the switch circuit board 201 used depending on the test conditions of the transistor 117 does not require changing the wiring of the connection wiring 211, but only requires changing the position of the opening 216 into which the fork plug 205 is inserted. Also, the switch circuit board 201 only requires changing the position of the connector 213 that connects to the mother board 207.

As shown in Figures 9, 11, 29, 30, etc., the connection wiring 211b connected to the transistor 117 is connected to the fork plug 205c. The connection wiring 211a connected to the transistor 117 is connected to the fork plug 205e.

Even if there are multiple transistors 117 to be tested, a single switch circuit board 201a will suffice for the purpose. This is because the output current Ia of the current power supply circuit 121a can be made to flow to the ground line as Im.

Switch circuit boards 201b are required for the number of transistors 117 to be tested. For example, if there are 12 transistors 117 to be tested, it is preferable to prepare 12 switch circuit boards 201b. It is also cost-effective to make switch circuit boards 201a and 201b have the same specifications.

A plurality of transistors or the like are mounted on the switch circuit board 201 as the switch circuits 124. The greater the number of switch circuits 124, the smaller the impedance of the short circuit between the two conductive plates 204. The number of switch circuits 124b mounted on the switch circuit board 201a is determined so that the on-resistance of the switch circuit 124b is smaller than the on-resistance of the transistor 117 to be tested.

Figures 27 and 28 show the state in which the fork plug 205 is inserted into the opening 216 of the partition wall 214. Figure 27 is a view from the front side of the partition wall 214, and Figure 28 is a view from the back side of the partition wall 214.

As an example, fork plug 205b and multiple fork plugs 205c (fork plugs 205c1 to 205c5) are connected to conductor plate 204b in FIG. 27. Fork plug 205e1 is connected to conductor plate 204d1, fork plug 205e2 is connected to conductor plate 204d2, fork plug 205e3 is connected to conductor plate 204d3, fork plug 205e4 is connected to conductor plate 204d4, and fork plug 205e5 is connected to conductor plate 204d5.

A transistor 117 to be tested is connected between the fork plug 205c and the fork plug 205e. The number of switch circuit boards 201b corresponding to the number of transistors 117 to be tested is mounted on the mother board 207. The openings 216 are formed to correspond to the positions of the conductor plates 204 of the switch circuit boards 201.

Although not shown, large noise is generated when the switch circuit 124 of the switch circuit board 201 is turned on and off. As a countermeasure to this, a metal plate is placed between the switch circuit boards 201 and is earthed.

In each drawing, one switch circuit 124 is shown on the switch circuit board 201. However, in reality, multiple switch circuits 124 are arranged between the conductor plates 204. By arranging multiple switch circuits 124 on the switch circuit board 201, it is possible to short-circuit the conductor plates 204 (for example, between conductor plates 204c and conductor plates 204e) with low resistance.

The heat generated by the switch circuit 124 is dissipated to the conductor plate 204. A heat sink is also attached to the switch circuit 124. The ground terminal of the switch circuit 124 is connected to the ground of the switch circuit board 201, and heat is also dissipated through the copper foil of the ground.

As shown in FIG. 9, two conductive plates 204 are attached to the switch circuit board 201, and the switch circuit 124 is arranged to short the two conductive plates 204. Also, FIG. 29 is an equivalent circuit diagram of the semiconductor device testing device of the present invention in the first embodiment.

As shown in Figures 9, 10, 11, etc., conductive plates 204a and 204b are attached to switch circuit board 201a. Conductive plate 204a is connected to fork plug 205a. Fork plug 205a is connected to the output terminal of current power supply circuit 121a. Conductive plate 204b is connected to fork plug 205b. Fork plug 205b is connected to the ground terminal of current power supply circuit 121a.

When the switch circuit 124b is turned on, the output terminals of the current power supply circuit 121a are short-circuited, and a short-circuit current Im flows. Therefore, the output current of the current power supply circuit 121a is not supplied to the transistor 117. When the switch circuit 124b is open, the output current Ia of the current power supply circuit 121a is supplied to the transistor 117.

Conductive plates 204c and 204d are attached to switch circuit board 201b. Conductive plate 204c is connected to fork plug 205d. Fork plug 205d is connected to the output terminal of current power supply circuit 121a. Conductive plate 204d is connected to fork plug 205e. Fork plug 205e is connected to the collector terminal of transistor 117 to be tested.

As shown in Figures 9, 10, 27, 28, etc., fork plug 205e is inserted into opening 216 in bulkhead 214 and is coupled to conductive plate 204d. Fork plug 205c is inserted into opening 216 in bulkhead 214 and is coupled to conductive plate 204d.

A switch circuit 124a is arranged on the switch circuit board 201b, and when the switch circuit 124a is turned on, the output current Ia from the current power supply circuit 121a is supplied to the transistor 117 as a test current Id to be passed through the transistor 117.

The switch circuit board 201b is placed in the B room of the housing 210, and the switch circuit board 201b is electrically connected to the transistor 117 to be tested by a fork plug 205 inserted from the C2 room through the opening 216 in the partition wall 214.

As shown in Figures 9, 10, 27, 28, etc., fork plug 205 and conductor plate 204 are connected. In Figure 10, switch circuit boards 201 are illustrated as being arranged in parallel. In reality, switch circuit boards 201 are inserted in parallel and arranged in a board rack. A mother board is arranged on the side of the board rack, and control signals to each circuit board are applied from the mother board.
The method for testing a semiconductor device according to the present invention will be described below. Figures 29, 30 and 31 are explanatory diagrams of the method for testing a semiconductor device according to the first embodiment of the present invention.

The constant current circuit 118 supplies a constant current Ic to the diode Di of the transistor 117. The operational amplifier circuit 116 buffers and outputs the terminal voltage Vi of the diode Di. The terminal voltage Vi is applied to the temperature measurement circuit 115, which determines temperature information Tj of the transistor 117 from the terminal voltage Vi and transfers it to the controller 111. The temperature information is output from the connector 213 of the device control circuit board 209 to the mother board 207 and sent to the control circuit board 111 (see FIG. 26, etc.).

The gate driver circuit 113 outputs an on-voltage Vg that turns on the gate of the transistor 117 at a set frequency and for a set on-voltage time. As an example, as shown in FIG. 31(a), the on-off cycle of the transistor 117 is tcycle, the on-time is ton, and the off-time is toff.

31(a), the transistor 117 is controlled to be turned on and off. The gate driver circuit 113 is controlled by the gate signal control circuit 112.
The current power supply circuit 121 a outputs a constant current Ia, which is supplied as Id to the transistor 117 .

The Vgs signal voltage output from the gate driver circuit 113 turns transistor 117 on and off, and a current Id flows between the channels of transistor 117 while transistor 117 is on.

The gate driver circuit 113 has a variable resistance circuit 125 inside. The value of the variable resistance circuit 125 is configured so that it can be set to a predetermined value or in steps between 0 (Ω) and 500 (Ω). The value of the variable resistance circuit 125 may be set by a control signal from the control circuit board (controller) 111 while observing the waveform of the gate terminal g.

A resistor R (not shown) may be placed between the gate terminal g and the emitter terminal e or collector terminal c of the transistor 117. By adjusting the value of the resistor R, the slope angle of the rising and falling voltage waveforms of the gate signal can be adjusted.

When the value of the variable resistance circuit 125 is large, the slope of the rising/falling waveform of the gate signal of transistor 117 applied to the gate terminal of transistor 117 becomes gentler.

On the other hand, if the resistance value of the variable resistance circuit 125 is small, the slope of the rising/falling waveform of the gate signal becomes steep. By changing the value of the variable resistance circuit 125 or setting it to a predetermined value, the on-time of the transistor 117 can be adjusted.

The gate driver circuit 113 can set the slope of the rising waveform (rise time Tr) and the slope of the falling waveform (fall time Td) for the gate voltage applied to the gate terminal g of the transistor 117. By separately adjusting the rise time Tr and the fall time Td, the on time of the transistor 117 can be adjusted as desired.

The resistance value of the variable resistance circuit 125 is set by the control circuit board (controller) 111. The setting is not limited to a constant value. The slope of the rising waveform (rise time Tr) and the slope of the falling waveform (fall time Td) of the gate driver circuit 113 may be changed. The resistance value at the rising edge and the resistance value at the falling edge of the gate signal may be changed. The resistance value may also be variably controlled in real time. By variably controlling the variable resistance circuit 125, the on-time of the transistor 117 is stabilized.

When the resistance value at the rising edge of the gate signal is reduced, the waveform of the on-voltage applied to the gate terminal of transistor 117 becomes steeper, and transistor 117 turns on quickly. When the resistance value at the rising edge of the gate signal is increased, the waveform of the on-voltage applied to the gate terminal of transistor 117 becomes gentler, and transistor 117 turns on slowly.

When the resistance value at the falling edge of the gate signal is reduced, the waveform of the on-voltage applied to the gate terminal of transistor 117 becomes steeper, and transistor 117 turns off quickly. When the resistance value at the falling edge of the gate signal is increased, the waveform of the on-voltage applied to the gate terminal of transistor 117 becomes gentler, and transistor 117 turns off slowly.

As described above, it is possible to control, adjust, or set the value of the variable resistance circuit connected to the gate terminal of transistor 117, or the rise time/fall time of gate driver circuit 113. Therefore, as a function of gate driver circuit 113, it is possible to change or modify the inrush current Is and surge voltage Vs generated in transistor 117.

It goes without saying that the operation of transistor 117 can be achieved not only by controlling the on-voltage of the gate terminal of transistor 117, but also by changing or setting the value of the constant current Id or voltage Vm supplied to transistor 117 by current power supply circuit 121.

The variable resistance circuit 125 of the gate driver circuit 113 is controlled by a control circuit board (controller) 111. The cycle time tcycle, on time ton, and off time toff of the gate signal output by the gate driver circuit 113 shown in FIG. 31 are controlled by a gate signal control circuit 112, and the gate signal is applied to the gate terminal of a transistor 117. The gate signal control circuit 112 is also controlled by the control circuit board (controller) 111.

11, 29, 30, etc., the resistance value of the variable resistance circuit 125 of the gate driver circuit 113 is variable, but this is not limiting. For example, it goes without saying that the variable resistance circuit 125 may be an external resistor, and the resistor may be connected to the gate terminal of the transistor 117 by a connector (not shown) or the like.
The value of the resistor to be connected is set by observing the waveform of the gate terminal of the transistor 117 and the waveform of the channel current Id.

In Figures 11, 29, 30, etc., a constant current circuit 118 is connected between the collector terminal c and the emitter terminal e of the transistor 117. The constant current circuit 118 passes a predetermined constant current Ic. The constant current Ic is for monitoring the temperature of the transistor 117.

In this specification, an IGBT is used as an example for explanation, so the terminals of the transistor 117 are the gate terminal g, the collector terminal c, and the emitter terminal e. In the case of a MOS transistor 117, the terminals of the transistor 117 are the gate terminal g, the drain terminal d, and the source terminal s.

A body diode or a channel diode Di is formed in the transistor 117. Note that the diode Di may be a diode of a separate semiconductor chip mounted on the semiconductor chip in which the transistor 117 is formed.

The diode Di may be a parasitic diode formed secondarily when the transistor 117 is formed. The parasitic diode is formed secondarily due to the layer structure of the transistor 117. The diode Di is formed near the channel portion of the transistor 117 due to its structure.

The diode Di may be any element that does not operate when the transistor 117 is operating. For example, it is not limited to a diode, and it goes without saying that a transistor may be used in a diode connection.

In addition, the device is not limited to a semiconductor such as a diode, but may be a device such as a resistor. A constant current Ic is applied to a device such as a resistor to measure the terminal voltage of the resistor. This voltage is measured as voltage Vi.

As described above, the element that acquires the temperature can be not only a semiconductor device, but also a resistor or other device. In other words, any device that can acquire a voltage value by passing a current, or a current value by applying a voltage, can be used.

The resistance value of the diode Di changes due to heat generation by the transistor 117. When a constant current Ic flows through the diode Di, the voltage between the terminals of the diode Di changes in proportion to the change in the resistance value of the diode Di. By monitoring or measuring the voltage between the terminals, the temperature or the change in temperature of the transistor 117 can be known.
In order to monitor the temperature of the transistor 117 from the voltage of the diode Di, it is necessary to obtain the temperature coefficient in advance.

The temperature coefficient is determined by setting the transistor 117 to a predetermined temperature in a thermostatic chamber, passing a constant current Ic through the diode Di, and measuring the terminal voltage of the diode Di. By varying the predetermined temperature and measuring the terminal voltage of the diode Di, the terminal voltage of the diode with respect to temperature can be obtained. Therefore, the temperature coefficient K of the transistor 117 can be obtained from the terminal voltage of the diode Di with respect to temperature.

The temperature coefficient K may differ for each production lot of transistor 117, but generally it shows a constant value for the production lot. Therefore, if the transistor 117 to be tested is sampled from each production lot and the temperature coefficient K is calculated, it can be used for the temperature coefficient K of other transistors 117.

To obtain the temperature coefficient K with high accuracy, the temperature coefficient K of each transistor 117 is measured and tested individually, even for the same lot. Measurement of the temperature coefficient K is not limited to using a thermostatic bath. For example, the temperature coefficient K can be obtained by changing the temperature of the water flowing through the heat sink on which the transistor 117 is mounted.

During testing, a test current Id is applied intermittently to transistor 117. Immediately after the test current Id is turned off, or after a short, predetermined time has elapsed after it is turned off, a constant current Ic for temperature measurement is passed from constant current circuit 118.

To prevent the constant current Ic from heating the transistor 117 or to avoid any influence of the constant current Ic, the constant current Ic is set to a current value that is sufficiently smaller than the constant current Id passed through the channel of the transistor 117. The constant current Id is set to a current that does not generate heat that would affect the temperature measurement.

Specifically, the constant current Ic is set to 1/1000 or less of the current Id passed through the transistor 117 during testing. Preferably, the current Ic passed through the transistor 117 is set to 1/1×106 or more and 1/1×104 or less of the current Id. The constant current Ic is set to 0.1 mA or more and 100 mA or less.

The channel current Id is changed, the diode Di voltage (the voltage between the collector and emitter terminals of transistor 117) is measured, and the temperature coefficient K is calculated. The calculated temperature coefficient K is stored in the temperature measurement circuit 115.

When measuring temperature, if the diode Di is formed in the same chip as the transistor 117, the saturation voltage Vn may change depending on the gate voltage Vgs. It is preferable that the gate voltage Vgs be zero (0) voltage or a negative voltage (minus voltage).

As shown in FIG. 8, based on the temperature information Tj, the control circuit board (controller) 111 controls the chiller 136. The chiller 136 adjusts the temperature of the circulating water (circulating solution) and adjusts the temperature of the heating and cooling plate 134.

In the above embodiment, the temperature coefficient K is calculated in advance, but the semiconductor testing method of the present invention is not limited to this. Temperature information Tj of the transistor 117 is calculated from the temperature coefficient and the diode terminal voltage, etc.
The transistor 117 is disposed in close contact with the heating/cooling plate 134 so that the temperature of the heating/cooling plate 134 is substantially equal to that of the transistor 117 .

The control circuit board (controller) 111 controls the chiller 136 to set the temperature of the heating/cooling plate 134 to a predetermined temperature, applies a constant current Ic to the transistor 117, and measures the terminal voltage of the diode Di.

From the measurement results, the temperature coefficient K is calculated. The temperature of the heating/cooling plate 134 is set to multiple temperatures, and the temperature coefficient K at each temperature is calculated, and the accuracy of the temperature coefficient value is improved from the results.

The temperature coefficient K is calculated by heating the transistor 117 to a predetermined temperature using the heating/cooling plate 134, passing a constant current Ic through the diode Di, and measuring the terminal voltage. By varying the predetermined temperature and measuring the terminal voltage of the diode Di, the terminal voltage of the diode Di versus temperature can be obtained. Therefore, the temperature coefficient K of the transistor 117 can be calculated from the terminal voltage of the diode Di versus temperature.

When testing transistor 117, constant current Ic is passed through diode Di when channel current Id is not flowing. In other words, when transistor 117 is not on, constant current Ic is passed and the voltage between the terminals of diode Di is measured.

The operational amplifier circuit (buffer circuit) 116 outputs the terminal voltage Vi (terminal c-terminal e) of the diode Di. Note that the operational amplifier circuit 116 is not limited to one composed of an operational amplifier element. Any circuit having high input impedance and low output impedance may be used.
The temperature measuring circuit 115 obtains temperature information Tj of the transistor 117 being tested from the stored temperature coefficient K and voltage Vi.

The obtained temperature information Tj is sent to the control circuit board (controller) 111. When the temperature information Tj reaches or exceeds a predetermined set value, the control circuit board (controller) 111 determines that the transistor 117 is in a predetermined stress state or deteriorated state, and changes the control of the test or stops the test.

The main area where a transistor deteriorates during testing is often the junctions within the transistor 117. The semiconductor itself does not deteriorate, but the junctions (bonding, die bonding, etc.) of the transistor 117 deteriorate, causing the resistance of the junctions to increase. As the resistance increases, the voltage Vce increases, generating heat and raising the temperature of the transistor 117.

When a semiconductor deteriorates, it is often the deterioration of the gate oxide film (insulating film) of transistor 117. When the gate oxide film deteriorates, the oxide film (insulating film) is short-circuited and the voltage Vce drops. Alternatively, transistor 117 is turned off, no current flows through transistor 117, and the voltage Vce rises to the maximum value of the power supply voltage.

At the start of the test, the temperature information Tj varies between the minimum temperature T1 and the maximum temperature T2. When the transistor 117 is subjected to stress by the test, the Vce voltage of the transistor 117 varies, and the temperature information Tj generally varies in the increasing direction.
Therefore, as shown in FIG. 32(c), the minimum temperature rises above temperature T1, and the maximum temperature approaches temperature information Tm (Tjmax).
In the semiconductor testing method of the present invention, the test is terminated under any of the following conditions:
When the temperature information Tj falls outside a predetermined range.
When the channel voltage Vce falls outside a predetermined voltage range.
- If the thermal resistance is outside the specified range.

In the examples of Figures 11, 29, 30, etc., switch circuit Ssa124a and switch circuit Sab124b use the symbols for switch circuits. Any element can be used as the switch circuit for switch circuit Ssa124a and switch circuit Sab124b as long as the resistance (on resistance) when closed (on) is small. Examples include transistors, mechanical relays, phototransistors, and photodiode switches.

Figure 30 is an equivalent circuit diagram of a semiconductor device testing device in the first embodiment of the present invention. In this embodiment, the switch circuit Ssa and the switch circuit Sab use a power MOSFET 124 as shown in Figure 30. The voltage (Vsd) between the channels of a power MOSFET is small.

Note that the switch circuit may be something other than a power MOSFET. Needless to say, the switch circuit Ssa and the switch circuit Sab may be power transistors or the like, in addition to power MOSFETs. Other examples include electromagnetic relays and electromagnetic switches.

The channel voltage (Vsdb) of the power MOSFET 124b when on is selected to be equal to or lower than the channel voltage (Vsda) of the power MOSFET 124a when on. In other words, the channel voltage (Vsdb) of the power MOSFET 124b when on is set to be smaller than the channel voltage (Vsda) of the power MOSFET 124a when on. This is to completely short-circuit the terminals of the current power supply circuit 121a when the switch circuit 124b is turned on, allowing the current Im to flow stably.
The above also applies when the switch circuit 124 is a power transistor, etc. In the case of the power transistor 124, the channel voltage is Vce.
When the switch circuit 124a is turned on, the current Ia outputted from the current power supply circuit 121a can be supplied to the transistor 117 as the test current Id.

Figure 31 is an explanatory diagram of a method for testing a semiconductor element of the present invention in the first embodiment. In Figure 31, Vgs is a gate signal applied to the gate terminal of the transistor 117 to be tested. Id is a current passed through the transistor 117 during testing. For ease of explanation, it is assumed that a constant current Ia passes when the transistor 117 is on.

In Fig. 31 (c), St1 is a timing signal for passing a current Ic through the diode Di, and when St1 is at H level, a current flows through the diode Di of the transistor 117. The operational amplifier circuit 116 acquires the terminal voltage of the diode Di, and the temperature measurement circuit 115 converts the terminal voltage into temperature information Tj. The temperature information Tj is sent to the control circuit board (controller) 111, which then tests the transistor 117 (semiconductor element 117) according to the temperature information Tj.

Id is a current flowing through the transistor 117 to be tested, and is a current output from the current power supply circuit 121. St1 and St2 are times during which a measurement current flows through a diode for temperature measurement, or times during which the temperature is measured.
FIG. 31(e) Ssa is the on/off signal of the switch circuit 124a, and FIG. 31(f) Sab is the on/off signal of the switch circuit 124b.

Figure 31 (g) Vce indicates the voltage at terminal c of transistor 117 (channel voltage of transistor 117), and temperature information Tj indicates the measured temperature change of transistor 117.

As shown in FIG. 31(a), a gate signal Vgs is applied from the gate driver circuit 113 to the gate terminal g of the transistor 117. The gate signal Vgs has a cycle time tcycle and an on-time ton. The cycle time tcycle and the on-time ton can be set to any value by the gate signal control circuit 112. The on-voltage Vg can also be set to any voltage.

Figure 31 (d) St2 is a timing signal that causes current Ic to flow through diode Dsa and diode Dsb in the embodiment shown in Figure 34. When St2 is at H level, current flows through diode Dsa or Dsb of transistor 117. This is the case where temperature information Tj is obtained by passing a constant current Ic through a device (diode) independent of transistor 117.

The operational amplifier circuit 116 acquires the terminal voltage of the diode Dsa or Dsb, and the temperature measurement circuit 115 converts the terminal voltage into temperature information Tj. The temperature information Tj is sent to the control circuit board (controller) 111, which tests the transistor 117 based on the temperature information Tj. Note that matters related to St2 will be explained in FIG. 34 etc.

For ease of understanding, the measured temperature information Tj will be described as changing between T1 and T2 as shown in FIG. 31(h). The temperature information Tj increases when a current is passed through the transistor 117, and decreases when the current is stopped. The temperature information Tj also changes with changes in the characteristics of the transistor 117.

Figure 31 (e) Ssa shows the timing of the on/off control signal for the switch circuit Ssa. When Ssa becomes Von, the switch circuit Ssa closes (turns on). When it is 0, the switch circuit Ssa opens (turns off), and the application of current or voltage is cut off.

Figure 31 (f) Ssb shows the timing of the on/off control signal for the switch circuit Ssb. When Ssb becomes Von, the switch circuit Ssb closes (turns on). When it is 0, the switch circuit Ssb opens (turns off).

Figure 31 (g) Vce is the channel voltage (voltage between the emitter terminal and collector terminal) of transistor 117. As transistor 117 is turned on and off, surge voltage and surge current are generated, and the Vce waveform changes in a complex manner over time as the on-resistance of transistor 117 changes. In addition, the Vce waveform of transistor 117 changes as current Ic flows through diode Di.

In this specification and drawings, for ease of explanation or drawing, it is assumed that when the transistor 117 is on, the voltage is Vn, and when the transistor is off, the voltage is Ve.
The gate signal is applied to the gate terminal of the transistor 117 under test with a period tcycle, an on time ton, and an off time toff.

When transistor 117 is an N-channel transistor, the gate signal Vgs has a ground (earth) voltage of 0 (V) as its off voltage and Vg as its on voltage. When transistor 117 is a P-channel transistor, it changes the potential of the on voltage and the off voltage.

During a period tn2 before the transistor 117 is turned on, the Vt voltage is set to a voltage more negative than the off voltage. Also, during a period tn1 after the transistor 117 is turned off, the Vt voltage is set to a voltage more negative than the off voltage.
The Vt voltage is a voltage lower than 0 (V) and higher than −4 (V). Therefore, Vt is a voltage equal to or higher than −4 (V) and lower than 0 (V).

When the transistor 117 is SiC, the off voltage is the Vt voltage, and when it is an IGBT, the off voltage is 0 (V). As described above, the semiconductor element testing device of the present invention is configured so that the off voltage supplied to the transistor 117 can be changed depending on the type of transistor 117 being tested.

When the Vt voltage is applied, St1 (St2) is set to H level to measure the temperature of transistor 117. A constant current Ic is passed through diode Di while the Vt voltage is being applied. In addition, a constant current Ic is passed while St1 (St2) is set to H level.

By applying the Vt voltage to the gate terminal of transistor 117, the off state of transistor 117 becomes stable, and the measurement of temperature information Tj can be performed stably. In addition, noise is less likely to be introduced when measuring temperature information Tj, improving the measurement accuracy of temperature information Tj.

By applying the Vt voltage to the gate terminal of transistor 117, the leakage current of transistor 117 is reduced, improving the measurement accuracy of the Vi voltage and stabilizing the measurement.

The gate signal Vgs is set to the Vt voltage during times tn1 and tn2. As an example, the times tn1 and tn2 are between 0.2 ms and 2 ms. Transistor 117 is turned off at 0 (V).

Therefore, three voltages, Vg, 0 (V), and Vt, are applied to the gate terminal g of transistor 117. During the period when Vt is being applied, a current is passed through the diode Di of the transistor to measure the temperature information Tj.

When a constant current Ic is passed through the diode Di, the switch circuit Ssa is turned off so that the current from the current power supply circuit 121a is not applied to the transistor 117.

By passing a constant current Ic through the diode Di, the terminal voltage of the diode Di is obtained, and the operational amplifier circuit 116 outputs the Vi voltage corresponding to the terminal voltage. The Vi voltage is input to the temperature measurement circuit 115, which obtains temperature information Tj corresponding to the temperature of the transistor 117.

The temperature information Tj is transferred to a control circuit board (controller) 111, which controls the test of the transistor 117 (semiconductor element 117) by continuing, stopping, changing the conditions of the test of the transistor 117, etc., based on the temperature information Tj.

Figure 31 (e) Ssa is a timing signal that controls the on/off state of switch circuit 124a. Figure 31 (f) Ssb is a timing signal that controls the on/off state of switch circuit 124b.

The switch circuit 124a turns on with a delay of tm2 after the Vgs signal of the transistor 117 becomes Vg. The tm2 time can be changed and set by the control circuit board (controller) 111.

The switch circuit 124b turns on a time tb2 before the switch circuit 124a turns on. The on state of the switch circuit 124b is maintained until tb1 after the switch circuit 124a turns on. The times tb2 and tb1 can be changed independently.
In particular, the setting of tb1 is important. The time tb1 is appropriately set or changed by observing the waveform of the Vce voltage of the transistor 117.

The switch circuit 124a turns off tm1 before the Vgs signal of the transistor 117 becomes Vt. The tm1 time can be changed and set by the control circuit board (controller) 111.

The switch circuit 124b turns on a time ta2 before the switch circuit 124a turns off. The on state of the switch circuit 124b is maintained until ta1 after the switch circuit 124a turns off. The times ta2 and ta1 can be changed and set independently.
In particular, the setting of ta1 is important. The time ta1 is appropriately set or changed by observing or measuring the waveform of the Vce voltage of the transistor 117.

When the switch circuit Ssb is turned on, the output terminal of the current power supply circuit 121a is shorted to the ground (ground line), and the charge is discharged. As a result of the charge being discharged, the terminal voltage of the current power supply circuit 121a becomes 0 (V) (ground voltage). In addition, the current Ia output by the current power supply circuit 121a is passed to the ground (ground) as a current Im. Therefore, the current Ia is not applied to the transistor 117, and the collector voltage of the transistor 117 does not rise.

The time tb2 is set by observing or measuring the time when the output voltage of the current power supply circuit 121a becomes 0 (V) or close to 0 (V), or the time when the output voltage of the current power supply circuit 121a becomes lower than the collector voltage of the transistor 117.

At the time when the voltage relationship reaches a predetermined value (after tb2 has elapsed), the switch circuit 124a is turned on to apply the current Ia (=Id) from the current power supply circuit 121a. However, since the switch circuit 124b is on at this time, the current Ia (=Id) from the current power supply circuit 121a flows to the ground (ground line) as the current Im via the switch circuit 124b. Therefore, the constant current Id does not flow through the transistor 117.
After the switch circuit 124 a is turned on and a time tb 1 has elapsed, the switch circuit 124 b is turned off and the test current Id is supplied to the transistor 117 .
The test current Id is supplied to the transistor 117 in synchronization with the switch circuit 124a as shown in FIG.

By operating the switch circuits 124a and 124b as described above, the surge voltage Vs or inrush current Is is not applied to the transistor 117. Alternatively, the surge voltage Vs or inrush current Is is suppressed, allowing a good test of the transistor 117 to be performed.

When the test current Id to the transistor 117 is stopped, the switch circuit 124b is turned on before the switch circuit 124a is turned off (ta2). The constant current Ia output by the current power supply circuit 121a flows to ground as the current Im via the switch circuit Ssb and is not supplied to the transistor 117.

The time ta2 is set by observing the time when the output voltage of the current power supply circuit 121a becomes 0 (V) or close to 0 (V), or the time when the output voltage of the current power supply circuit 121a becomes lower than the collector voltage of the transistor 117.

When the above voltage relationship reaches a predetermined value (after ta2 has elapsed), switch circuit 124a is turned off. After ta1 time has elapsed since switch circuit 124a was turned off, switch circuit 124b is turned off.

By operating or controlling the switch circuits 124a and 124b as described above, the surge voltage Vs or inrush current Is is not applied to the transistor 117. Alternatively, the surge voltage Vs or inrush current Is is suppressed, and a good test of the transistor 117 can be performed.

The temperature information Tj increases when the constant current Id is supplied to the transistor 117. The temperature information Tj decreases when the constant current Id to the transistor 117 is stopped. The temperature information Tj fluctuates between T1 and T2. When the characteristics of the transistor 117 fluctuate due to the test, the temperature information Tj gradually increases.
In order to apply a constant current Id to the transistor 117, the current power supply circuit 121a is operated to apply a current Id (=Ia) to the transistor 117.

As shown in Figures 11, 29, 30, 32, 34, 35, etc., the resistance value of the variable resistor circuit 125 of the gate driver circuit 113 can also be set. By increasing the resistance value, the rising/falling waveform of the gate signal Vgs can be changed as shown by the dotted line or dashed line in Figure 32(a).

By changing or setting the gate signal Vgs, the current Id flowing through the transistor 117 can also be changed as shown by the dotted line or the dashed dotted line in FIG.
By changing the rising and falling waveforms of the current Id, it is possible to adjust or suppress the surge voltage or inrush current.

As shown in FIG. 32(c), the temperature information Tj changes from a solid line to a dotted line and from a dotted line to a dashed line as the characteristics of the transistor 117 change due to the test. The test is stopped when the temperature information Tj reaches the level of Tm. Alternatively, the test is stopped when the rate of change of the temperature information Tj reaches a predetermined value. The test conditions are also changed.

As shown in FIG. 33, when the switch circuit Ssa (switch circuit 124a) is in the off state, the St1 signal is set to H and the temperature information Tj is measured. The St1 signal is set to H level when the gate signal is Vt. During the tn2 period, the signal is set to H level during the tc2 period and the temperature information Tj is measured. During the tn1 period, the temperature information Tj is measured during the tc1 period.

The temperature information Tj measured during the period tc2 is the temperature information Tj at the time when the transistor 117 is cooled down. The temperature information Tj measured during the period tc1 is the temperature information Tj immediately after the current Id to the transistor 117 is stopped.
Stopping the test, changing the conditions, changing the control, etc. are determined based on the temperature information Tj measured during the period tc2 and the temperature information Tj measured during the period tc1.

If the rate of change of the temperature information Tj measured during the tc1 period is greater than that of the temperature information Tj measured during the tc2 period, or if the difference in absolute value between the temperature information Tj measured during the tc1 period and the temperature information Tj measured during the tc2 period is large, the test is controlled and modified in response to the measurement value temperature information Tj.

Furthermore, if the temperature information Tj measured during the period tc2 differs from the standard value by a predetermined value, it is determined whether there is a problem with the connection state of the transistor 117 or the test equipment, and a decision is made to "not start the test", etc.
During the period tc2 or tc1, Vi is measured multiple times to obtain temperature information Tj for Vi.

The embodiment in FIG. 34 is a semiconductor device testing device according to the second embodiment of the present invention. The transistor 117 in FIG. 34 is provided with a separate diode Ds (diode Dsa, diode Dsb) for temperature measurement. The diode Ds is formed in the same process as the transistor 117.

In the embodiment of FIG. 34, temperature information Tj is measured at the timing of the St2 signal in FIG. 31(d). When the switch circuit Ssa (switch circuit 124a) is in the off state, the St2 signal is set to H and temperature information Tj is measured. During the tn2 period, the signal is set to H level during the tc2 period and temperature information Tj is measured. During the tc1 period, temperature information Tj may be measured during either the ton period or the tn1 period. The temperature information Tj measured during the tc2 period and the temperature information Tj measured during the tc1 period are averaged to obtain the temperature information Tj.

During the period tc2 or tc1, Vi is measured multiple times to obtain temperature information Tj for Vi. The operations of other signals or switch circuits in Fig. 31 are the same as or similar to those in the embodiment described with reference to Fig. 11 and the like.
In the above embodiment, the temperature information Tj is measured by a diode added to or formed in the transistor 117 .
In the embodiment of FIG. 34, a diode Ds that is not connected (is independent) from the transistor 117 is formed.

Diode Dsa is oriented to pass constant current Ic. Diode Dsb is oriented to pass constant current Ic'. Constant current circuit 118 (Pc) generates constant current Ic and constant current Ic'.

Diodes Dsa and Dsb are diodes for measuring temperature. The structures of diodes Dsa and Dsb are similar or identical to the structure of diode Di in Figure 11, etc.

Diode Di is connected to the terminals (terminals c and e) of transistor 117, while diodes Dsa and Dsb are not connected to the terminals of transistor 117 but are connected to independent terminals, and temperature information Tj of diode Di is measured at timing St1 in Figure 31 (c), while temperature information Tj of diode Dsa and diode Dsb is measured at timing St2 in Figure 31 (d). Other than this, they have the same operation or configuration.

In the embodiment of FIG. 34, the diode Ds is separated from the path through which the constant current Id flows. Even when the current Id flows through the transistor 117, the constant current Ic can be passed through the diode. Therefore, the time for measuring the temperature information Tj can be freely set. The positions of tc1 and tc2 can be set as shown in FIG. 31(d).

However, in tc2, as shown in Fig. 31(d), the gate signal is placed or set in the period of Vt. The temperature information Tj measured in the period tc2 is used as the value before the transistor 117 operates. The period tc1 is preferably immediately before the constant current Id of the transistor 117 is stopped. It may also be immediately after the constant current Id is stopped. It is preferable that "immediately before" and "immediately after" are within 1 ms.
St2 in FIG. 31(d) is a timing signal for causing the current Ic (or current Ic') to flow through the diode Ds (Dsa, Dsb).

When St2 is at H level, a current flows through the diode Ds (Dsa, Dsb) of the transistor 117. The operational amplifier circuit 116 acquires the terminal voltage of the diode Ds, and the temperature measurement circuit 115 converts the terminal voltage into temperature information Tj.

The temperature information Tj is sent to the control circuit board (controller) 111, which performs, stops, or changes the control of the test of the transistor 117 according to the temperature information Tj.

When St2 is at the H level, the constant current circuit 118 passes a constant current Ic, which flows through the diode Dsa. The constant current circuit 118 also passes a constant current Ic', which flows through the diode Dsb.

The constant current Ic and the constant current Ic' are currents of the same magnitude. However, when the threshold voltages of the diodes Dsa and Dsb are different, or when the characteristics of the diodes Dsa and Dsb are different, it is preferable to make the constant current Ic and the constant current Ic' different in magnitude.

The operational amplifier circuit 116 acquires the terminal voltage of the diode Dsa or Dsb, and the temperature measurement circuit 115 converts the terminal voltage into temperature information Tj. The temperature information Tj is sent to the control circuit board (controller) 111, which then tests the transistor 117 based on the temperature information Tj.

The temperature information Tj obtained by passing a constant current Ic and the temperature information Tj obtained by passing a constant current Ic' are averaged or weighted to obtain a single value of temperature information Tj. Using this temperature information Tj, the control circuit board (controller) 111 performs or stops the test of the transistor 117, or changes the control.
The other matters are the same as or similar to the matters or contents described in this specification and drawings, and therefore will not be described here.

It goes without saying that the present invention can be modified in various ways without departing from the spirit and scope of the invention. It goes without saying that the matters or contents described in this specification and drawings can be combined with each other.

Figure 35 is an explanatory diagram of a semiconductor element testing device in a third embodiment of the present invention. The difference from Figure 11 is that a diode-connected transistor 117s is placed in the path of a current Id that flows through a transistor 117m to be tested. Other parts are the same, so the explanation is omitted.

As an example, transistor 117s is a transistor with the same specifications as transistor 117m to be tested. The gate terminal g2 and emitter terminal e2 of transistor 117s are connected, and transistor 117s can be considered equivalent to a diode. The gate terminal g2 and emitter terminal e2 of transistor 117s are connected to the O terminal of element terminal 226. The collector terminal c2 of transistor 117s is connected to the P terminal of element terminal 226.

As shown in FIG. 7, the terminals of the transistor 117s (gate terminal g2, emitter terminal e2, collector terminal c2) are connected to the connector 202b, and the connector 202b is connected to the sample connection circuit 203 by the signal wiring 222b. The terminals of the transistor 117s (gate terminal g2, emitter terminal e2, collector terminal c2) are connected within the sample connection circuit 203.

When the switch circuit 124b is turned on, a current Im flows, discharging the charge in the current power supply circuit 121a. Alternatively, the current Ia output by the current power supply circuit 121a flows to ground via the switch circuit 124b.

When an inrush current Is flows through the transistor 117m being tested, the transistor 117m is destroyed by the inrush current Is or surge voltage Vs. To prevent the inrush current Is or surge voltage Vs from occurring, the on/off control and on/off sequence of the switch circuits 124a and 124b are controlled.

When testing transistor 117m by shortening the cycle tcycle, it is necessary to quickly turn on and off switch circuits 124a and 124b. In this case, an inrush current Is or a surge voltage Vs may occur depending on the on/off timing of switch circuit 124.

If the voltage Vm at the collector terminal of transistor 117 is higher than the voltage Vp at the output of the current power supply device, the current flows toward ground as current Im, and no current or only a small amount flows through transistor 117m.

In order to create the relationship Vm > Vp, in the embodiment shown in Figure 35, a diode-connected transistor 117s is placed in the path of current Id. When a current flows through transistor 117s, the voltage Vm is built up by the channel voltage of transistor 117s. Therefore, voltage Vp is lower than voltage Vm, and no inrush current is applied to transistor 117m. Transistor 117m will not be destroyed by inrush current Is or surge voltage Vs.

Figure 36 is an explanatory diagram of a semiconductor device testing device according to a fourth embodiment of the present invention. In Figure 36, multiple transistors 117 (transistors 117Q1 to 117Qn) to be tested are connected in parallel to a current power supply circuit 121.

In the fourth embodiment, there is one switch circuit board 201a and n switch circuit boards 201b (switch circuit board 201b1 to switch circuit board 201bn). There are n transistors 117Q (transistor 117Q1 to transistor 117Qn) that are tested simultaneously or sequentially.

The collector terminal of transistor Q1 is connected to fork plug 205e1, and the emitter terminal of transistor Q1 is connected to fork plug 205c1.

The collector terminal of transistor Q2 is connected to fork plug 205e2, and the emitter terminal of transistor Q2 is connected to fork plug 205c2.

The collector terminal of transistor Q3 is connected to fork plug 205e3, and the emitter terminal of transistor Q3 is connected to fork plug 205c3.

Similarly, the collector terminal of transistor Qn is connected to fork plug 205en, and the emitter terminal of transistor Qn is connected to fork plug 205cn.

When the switch circuit Ssa1 is turned on, the current Ic of the constant current circuit 118 is supplied to the diode Ds of the transistor 117Q1. The terminal voltage of the diode Ds is applied to the operational amplifier (buffer) 116 and is output from the operational amplifier circuit 116 as the Vi1 voltage.

When the switch circuit Ssa2 is turned on, the current Ic of the constant current circuit 118 is supplied to the diode Ds of the transistor 117Q2. The terminal voltage of the diode Ds is applied to the operational amplifier (buffer) 116 and is output from the operational amplifier circuit 116 as the voltage Vi2.

Similarly, when the switch circuit Ssan is turned on, the current Ic of the constant current circuit 118 is supplied to the diode Ds of the transistor 117Qn. The terminal voltage of the diode Ds is applied to the operational amplifier (buffer) 116 and is output from the operational amplifier circuit 116 as the voltage Vin.
One voltage is selected from the voltages Vi 1 and Vin by the selector 127 , and is output as Vi and input to the temperature measurement circuit 115 .

The temperature measuring circuit 115 obtains temperature information Tj and outputs it to the control circuit board 111. In the embodiment of Fig. 36, one constant current circuit 118 is used, but this is not limited to this. A constant current circuit 118 may be provided for each transistor 117Q. Also, a temperature measuring circuit 115 may be formed or provided for each transistor 117Q.
The voltage data Vi and the temperature information Tj are sent to the control circuit board 111 via the wiring of the mother board 207 .

The element terminal 226 (P terminal) of the transistor 117Q1 is connected to the connection structure 218a1. The element terminal 226 (N terminal) of the transistor 117Q1 is connected to the connection structure 218b1.

The element terminal 226 (P terminal) of the transistor 117Q2 is connected to the connection structure 218a2. The element terminal 226 (N terminal) of the transistor 117Q2 is connected to the connection structure 218b2.

Similarly, the element terminal 226 (P terminal) of the transistor 117Qn is connected to the connection structure 218an, and the element terminal 226 (N terminal) of the transistor 117Qn is connected to the connection structure 218bn, where n is a positive number equal to or greater than 1.
The connection structure 218 is inserted from an opening 216 provided in the partition wall 217. The connection structure 218 is inserted in the direction from the C2 chamber to the C1 chamber.

The fork plug 205 is inserted into chamber B from the C2 chamber side through an opening 216 formed in the partition wall 214. When the fork plug 205 is inserted, it is connected to the conductor plate 204 of the switch circuit board 201. The switch circuit board 201 can be selected depending on the position of the opening 216 into which the fork plug 205 is inserted.

The switch circuit board 201 to be selected by the fork plug 205 can be selected by changing the position of the switch circuit board 201 connected to the connector 213 of the mother board 207.

Two conductive plates 204 are arranged on the switch circuit board 201. The conductive plates 204 are arranged so that the conductive plate 204 closest to the C2 chamber is connected (contacted) to the fork plug 205.

In the embodiment of the present invention, the fork plug 205 and the conductor plate 204 are electrically connected by contacting each other, but this is not limited to this. Any configuration is acceptable as long as it is possible to change between an electrically connected state and a non-connected state by mechanical operation. In addition, any configuration is acceptable as long as it is possible to stably maintain the connected state.

For example, instead of the fork plug 205, a rotary connector, a rotary joint, a high-current connector, etc. may be used. Instead of the conductor plate 204, a rotary connector, a rotary joint, a high-current connector, a cylindrical conductor rod, a rectangular conductor rod, a comb-shaped conductor plate, etc. may be used.

In this specification and drawings, the conductor plate 204 is described as being a plate, but it is not limited to being a plate, and may be rod-shaped. Any shape may be used as long as it can be joined to a structure such as the fork plug 205. For example, it may be a structure such as a socket or connector. Also, the conductor plate 204 may be in the shape of a fork plug, and the fork plug 205 may be connected to the fork plug.

Figure 37 is an explanatory diagram of a method for testing a semiconductor element in an embodiment of the present invention, explaining the operation of Figure 36. It is possible to perform a semiconductor test by simultaneously turning on transistors 117Q (transistors 117Q1 to 117Qn). In this case, it is necessary to pass a constant current Id through all of transistors 117Q (transistors 117Q1 to 117Qn). Therefore, if there are n transistors 117Q, the current power supply circuit 121a must be able to output a current of Id x n (n is a positive number equal to or greater than 1). Therefore, a large-capacity current power supply circuit 121a is required.

If the test is performed by turning on the transistors 117Q in sequence and applying a constant current Id to the transistors 117Q, the constant current output by the current power supply circuit 121a can be Id. Figure 37 shows an example of a test method for a semiconductor element test device that performs a test by turning on the transistors 117Q in sequence. The semiconductor element changes depending on the number of times the constant current Id is turned on and off.

Therefore, by performing testing by sequentially turning on the semiconductor elements (transistor 117Q, etc.) as shown in FIG. 37, the testing can be performed efficiently and the maximum output current capacity of the current power supply circuit 121a can be reduced.

In FIG. 37, the number of transistors 117Q turned on is described as one, but this is not limited to this. For example, multiple transistors 117Q may be turned on simultaneously. In this case, the maximum value of the constant current output by the current power supply circuit 121a is the number of transistors 117Q turned on x Id.

In addition, in the embodiment of the present invention, one current power supply circuit 121a is illustrated, but the present invention is not limited to this. A current power supply circuit 121b may be installed separately from the current power supply circuit 121a. Furthermore, two or more current power supply circuits 121 may be installed. By installing multiple current power supply circuits 121, the current Id flowing through the transistor 117 can have various waveforms.
The above also applies to the embodiments of the present invention.

As shown in FIG. 37(a), when switch circuit St1 (151s1) to switch circuit Stn (151sn) are turned on, constant currents Id1 to Idn flow through transistor 117. For example, the application time of constant current Id is ton, and constant currents Id1 and Id2 are applied to transistor 117 sequentially at intervals of time tcycle. When transistor 117 is turned on, the channel voltage of transistor 117Q changes sequentially (FIG. 37(c)).

Therefore, for example, there is no overlap in time between the constant current Id1 and the constant current Id2. Therefore, the output capacitance of the current power supply circuit 121 can be the output capacitance required to test one transistor 117Q.

The constant currents Id (Id1 to Idn) are controlled so as not to overlap. It is also preferable to leave an interval of 1 μs or more between each of the constant currents Id (Id1 to Idn). The driving and control methods described in FIG. 31 are implemented for each transistor 117Q.

The constant current Ic supplied to each transistor 117Q is supplied to the diode Ds of each transistor 117Q by sequentially turning on the switch circuits Ssa (Ssa1 to Ssan).

A voltage Vi (Vi1 to Vin) corresponding to the terminal voltage of diode Ds is selected by the selector 127 in synchronization with the switch circuit Ssa (Ssa1 to Ssan). For example, when a current Ic is supplied to the transistor 117Q1, the selector 127 selects the terminal voltage of the diode Ds of the transistor 117Q1. When a current Ic is supplied to the transistor 117Q3, the selector 127 selects the terminal voltage of the diode Ds of the transistor 117Q3. The selected voltage Vi is supplied to the temperature measurement circuit 115.
The other configurations and operations are similar to those described in the other embodiments, and therefore the description thereof will be omitted.
In the embodiment of the present invention, the transistor 117 is an IGBT, but the present invention is not limited to this.

For example, it goes without saying that it may be an N-channel JFET (Figure 38(a)), a P-channel JFET (Figure 38(b)), an N-channel MOSFET (Figure 38(c)), a P-channel MOSFET (Figure 38(d)), an N-channel bipolar FET (Figure 38(e)), or a P-channel bipolar FET (Figure 38(f)).

Furthermore, the device is not limited to a three-terminal device, and may be a two-terminal element such as a diode as shown in FIG. 38(g). A two-terminal element does not require a gate signal Vgs. It goes without saying that the semiconductor element testing apparatus and semiconductor element testing method of the present invention can be applied by testing by passing a constant current Id from the current power supply circuit 121.

It goes without saying that the semiconductor element testing device and semiconductor element testing method of the present invention can be applied to other semiconductor elements such as thyristors and triacs, varistors, diacs, or modules in which transistors, diodes, resistors, etc. are mixed or integrated, without being limited to transistors and diodes.

In the above, the present specification has specifically described the present invention based on the embodiment, but it goes without saying that the present invention is not limited thereto and various modifications are possible without departing from the spirit of the present invention.
It goes without saying that the matters or contents described in this specification and the drawings can be combined with each other.

For example, the switch circuit 124a and the switch circuit 124b shown in FIG. 30 can be applied to other embodiments. For example, it goes without saying that the configurations or operations of FIG. 36 and FIG. 37 can be applied to other embodiments such as FIG. 34 and FIG. 35.

The present invention provides a semiconductor element testing device and a semiconductor testing method that can easily change connections depending on the test content of semiconductor elements such as transistors and the number of semiconductor elements to be tested simultaneously, and can effectively deal with noise generated during testing.

111 Control circuit board (controller)
112 Gate signal control circuit 113 Gate driver circuit 115 Temperature measurement circuit 116 Operational amplifier (buffer amplifier)
117 Power transistor 118 Constant current circuit 121 Current power supply circuit 122 Switch circuit 124 Switch circuit 125 Variable resistor circuit 126 Variable resistor circuit 127 Selector 128 Current detection circuit 129 Voltage detection circuit 130 Constant current setting circuit 131 Control rack 132 Power supply device 133 Control circuit 134 Heating and cooling plate 135 Circulating water pipe 136 Chiller 137 Short circuit 138 Insulated DC-DC converter circuit 201 Switch circuit board 202 Connector 203 Sample connection circuit 204 Conductive plate 205 Fork plug 206 Connection pin 207 Mother board 208 Connector 209 Device control circuit board 210 Housing 211 Connection wiring 212 Power supply wiring 213 Connector 214 Partition wall 215 Partition wall 216 Opening 218 Connection structure 219 Connection bolt 220 Contact portion 221 Fixing screw 222 Signal wiring 223 Heat pipe 224 Fixing screw 225 Contact portion 226 Element terminal 227 Cooling fan 228 Heat dissipation fin 231 Heat pipe metal fitting 232 Connection metal fitting 233 Connection metal fitting portion 234 Recess 236 Spring (pressure metal fitting)
237 Position fixing screw 238 Screw hole 239 Spring hole 240 Positioning screw hole 241 Fork plug insertion plate 251 Convex portion 252 Groove portion 301 Test circuit module 302 Voltage selection circuit 311 Pressing tool 312 Insulating plate 313 Pressing tool mounting plate 315 Insulating portion 322 Heating/cooling device 323 Support base 324 Electrical element insertion hole 325 Slide groove

Claims (8)

A power cycle test apparatus for testing a power transistor having a signal terminal and an element terminal, the power transistor being disposed on a heating/cooling plate to which a first circulating water pipe for introducing a liquid and a second circulating water pipe for discharging the liquid are attached, the power cycle test apparatus comprising:
A support stand;
A connection structure for connecting to the element terminal;
A connection wiring connected to the connection structure;
A signal wiring connected to the signal terminal;
A gate driver circuit connected to the signal wiring;
a terminal voltage measuring circuit connected to the signal terminal or the element terminal;
a power supply for supplying a test current or a test voltage;
a first switch circuit that supplies the test current or test voltage to an element terminal of the power transistor via the connection structure;
the connection structure is disposed on the support base, and the element terminal and the connection structure are connected to each other;
the gate driver circuit applies a signal voltage to the signal wiring to turn on or off the power transistor;
the terminal voltage measurement circuit measures a terminal voltage between the signal terminal or element terminal of the power transistor when the test current is not supplied to the power transistor;
the heating/cooling plate and the power transistor are disposed in a first chamber;
The power cycle testing apparatus according to claim 1, wherein the first switch circuit is disposed in a second chamber. A power cycle test apparatus for testing a power transistor having a signal terminal and an element terminal, the power transistor being disposed on a heating/cooling plate to which a first circulating water pipe for introducing a liquid and a second circulating water pipe for discharging the liquid are attached, the power cycle test apparatus comprising:
A support stand;
A connection structure for connecting to the element terminal;
A connection wiring connected to the connection structure;
A signal wiring connected to the signal terminal;
A gate driver circuit connected to the signal wiring;
a terminal voltage measuring circuit connected to the signal terminal or the element terminal;
a constant current circuit connected to the signal terminal or the element terminal;
a power supply for supplying a test current or a test voltage;
a first switch circuit that supplies the test current or test voltage to an element terminal of the power transistor via the connection structure;
a second switch circuit for shorting output terminals of the power supply device;
the connection structure is disposed on the support base, and the element terminal and the connection structure are connected to each other;
the gate driver circuit applies a signal voltage to the signal wiring to turn on or off the power transistor;
the constant current circuit supplies a constant current to the signal terminal or the element terminal;
the terminal voltage measurement circuit measures a voltage between the signal terminal or the element terminal to which the constant current is supplied when the test current is not supplied to the power transistor ;
the heating/cooling plate and the power transistor are disposed in a first chamber;
The power cycle testing apparatus according to claim 1, wherein the first switch circuit and the second switch circuit are disposed in a second chamber. 3. A power cycle testing device according to claim 1 , wherein a recess is formed in the connection structure, and a heat pipe is in intimate contact with the recess. Further comprising a cooling fan,
3. The power cycle testing device according to claim 1 , wherein the cooling fan is disposed on a side surface or a bottom surface of the connection structure. The connection structure has a connection part or a pressing tool and a connection fitting part,
The element terminal is sandwiched between the connection part or the pressing tool and the connection metal part, and connected;
3. The power cycle testing device according to claim 1, wherein the surface of the connection portion or the pressing tool is roughened. Further comprising a water leakage sensor for detecting the leaked liquid,
A channel is formed for drainage of the leaked liquid,
3. The power cycle testing device according to claim 1, wherein the operation of the power cycle testing device is stopped or an alarm is issued in response to the operation of the water leakage sensor. 3. The power cycle testing device according to claim 1, wherein the element terminal is arranged on a first end face of the power transistor, and the signal terminal is arranged on a second end face facing the first end face. the first switch circuit is mounted on a switch circuit board to which a first conductor plate and a second conductor plate are attached;
3. The power cycle testing device according to claim 1 , wherein the first switch circuit shorts the first conductive plate and the second conductive plate when the first switch circuit is turned on.

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