TWI617811B - Probe card - Google Patents

Abstract

The invention discloses a probe card, which comprises: a plurality of conductive probes; a first substrate; a probe fixing base disposed on the first substrate and used to fix the conductive probes; a second substrate, The circuit comprises a circuit for connecting the conductive probes; and a power transmission line and a signal transmission line for connecting the first substrate and the circuit.

Description

Probe card

The present invention relates to a probe card, and more particularly to a probe card that can provide the best signal integrity and power integrity.

During the manufacturing of integrated circuit components, electrical testing is performed before die cutting or component packaging. This is usually done by using a probe card to transmit the power signal and test signal provided by the tester to the component under test ( Device Under Testing (DUT for short); among them, the power signal is used to supply the power required by the device under test, and the test signal is used to detect the device under test.

The probe card 10 of the prior art can be seen in FIG. 1, and the structure main body is the printed circuit board 12, and the conductive probe 11 is fixed on the printed circuit board 12 through the probe fixing base 13. The power transmission line 15 and the signal transmission line 16 are connected to the conductive probes 11 by the printed circuit board 12, respectively. In addition, considering that the DUT often needs to perform high-frequency testing (for example, a test signal frequency exceeding 1.6Gbps), in order for the power signal to provide sufficient transient current, De-coupling Capacitor Cdc It will be soldered on the printed circuit board 12 and connected between the power transmission lines 15 to reinforce the transient current required by the DUT during high-frequency testing.

However, the decoupling capacitor Cdc set in this way can not only provide a limited reinforcement effect on the transient current mentioned above, it may even increase the DC offset of the power signal, and cause the malfunction of the DUT. Therefore, it is necessary to develop new probe card technology, so that when the device under test is subjected to high-frequency testing, problems such as transient currents and potential drifts that may occur in the power signal can be effectively suppressed.

One of the objects of the present invention is to solve the problem of high-frequency test when the component under test is under test. Signal may have transient current and potential drift issues to provide better signal integrity and power integrity.

According to an aspect of the present invention, an embodiment provides a probe card, which includes: a plurality of conductive probes; a first substrate; and a probe fixing base disposed on the first substrate and used to fix the conductive A probe; a second substrate including a circuit connected to the conductive probes; and a power transmission line and a signal transmission line connecting the first substrate and the circuit.

In one embodiment, the probe card further includes: a plurality of wires for connecting the circuit and the conductive probes, the length of which is less than a tenth of the length of the power transmission line or the signal transmission line.

In one embodiment, the power transmission line is a pair of twisted pairs, and the signal transmission line is a coaxial cable.

In an embodiment, the conductive probes include a first probe, a second probe, a third probe, and a fourth probe, the power transmission line includes a first transmission line and a second transmission line, and the signal transmission line includes a third A transmission line and a fourth transmission line, the circuit enables the first transmission line to be connected to the first probe, the second transmission line to be connected to the fourth probe, the third transmission line to be connected to the second probe, and the fourth transmission line to be connected to the first Three probes, and the circuit includes: a decoupling capacitor connecting the first probe and the fourth probe; a first resistor connecting the third transmission line and the second probe; and a fourth transmission line A second resistor connected to the third probe; and a third resistor connected to the third transmission line and the fourth transmission line.

In one embodiment, the conductive probes include a first probe, a plurality of second probes, a plurality of third probes, and a fourth probe. The power transmission line includes a first transmission line and a second transmission line. The signal The transmission line includes a third transmission line and a fourth transmission line. The circuit enables the first transmission line to be connected to the first probe, the second transmission line to be connected to the fourth probe, the third transmission line to be connected to the second probes, and the first Four transmission lines are connected to the third probes, and the circuit includes: a decoupling capacitor connecting the first probe and the fourth probe; and a plurality of first resistors respectively connecting the third transmission line and the corresponding first Two probes; a plurality of second resistors respectively connected to the fourth transmission line and the corresponding third probe; and a third resistor connected to the third transmission line and the fourth transmission line.

In one embodiment, the circuit further includes: a connection between the first transmission line and the first probe Pin power regulator.

100‧‧‧ Probe Card

110‧‧‧Conductive probe

111‧‧‧first probe

112‧‧‧Second Probe

113‧‧‧Third Probe

114‧‧‧ fourth probe

120‧‧‧First substrate

130‧‧‧ Probe Holder

140‧‧‧second substrate

145, 146, 147‧‧‧ circuits

150‧‧‧ Power Transmission Line

151‧‧‧The first transmission line

152‧‧‧Second transmission line

160‧‧‧Signal transmission line

161‧‧‧Third transmission line

162‧‧‧The fourth transmission line

170‧‧‧ Power Conditioner

180‧‧‧Wire

R1, R2, R3‧‧‧ resistance

Cdc‧‧‧ Decoupling Capacitor

FIG. 1 is a schematic structural diagram of a conventional technology probe card.

FIG. 2 is a schematic structural diagram of a probe card according to an embodiment of the present invention.

Fig. 3 is a circuit diagram of a second substrate circuit of the first example.

Fig. 4 is a circuit diagram of a second substrate circuit of the second example.

Fig. 5 is a circuit diagram of a second substrate circuit of the third example.

In order to further understand and understand the features, objects, and functions of the present invention, the embodiments of the present invention will be described in detail with reference to the drawings. Throughout the description and drawings, the same component numbers will be used to designate the same or similar components.

In the description of each embodiment, when an element is described as "above / above" or "below / below" another element, it refers to a situation where it is directly or indirectly above or below the other element. , Which may include other elements placed in between; the so-called "directly" means that no other intervening elements are placed in between. Descriptions such as "above / above" or "below / below" are described based on the drawings, but also include other possible direction changes. The so-called "first", "second", and "third" are used to describe different elements, and these elements are not restricted by such predicates. For the convenience and clarity of illustration, the thickness or size of each element in the drawings is shown in an exaggerated, omitted, or sketched manner, and the size of each element is not exactly its actual size.

FIG. 2 is a schematic structural diagram of a probe card 100 according to an embodiment of the present invention. The probe card 100 includes a plurality of conductive probes 110, a first substrate 120, a probe fixing base 130, a second substrate 140, a power transmission line 150, and a signal transmission line 160. The first substrate 120 may be a multilayer printed circuit board as a main structure of the probe card 100. The probe fixing base 130 itself is disposed and fixed on the first substrate 120 to fix the conductive probes 110 on the first substrate 120. The second substrate 140 may also be a multilayer printed circuit board to provide a circuit required for the electrical test of the device under test; the main function of the above circuit is to ensure the electrical test of the device under test. The signal integrity circuit and power integrity include at least a decoupling capacitor. The input end of the circuit is connected to the power transmission line 150 and the signal transmission line 160, and the output end is connected to the conductive probes 110. The power transmission line 150 is used to transmit the power signal provided by the tester to the above circuit via the first substrate 120, and the signal transmission line 160 is used to transmit the test signal provided by the tester to the above circuit via the first substrate 120 .

When conducting electrical testing of integrated circuit components, the needle tips of the conductive probes 110 will touch the testing pad of the device under test, thereby transmitting the signals provided by the testing machine to the device under test. The other ends of the conductive probes 110 are connected to the output terminal of the second substrate 140 circuit. As a result, the power signal provided by the external tester can be transmitted to the device under test in sequence through the first substrate 120, the power transmission line 150, the second substrate 140, and the conductive probes 110, and the provided The test signals are sequentially transmitted to the device under test through the first substrate 120, the signal transmission line 160, the second substrate 140, and the conductive probes 110. Please note that one of the features of the present invention is: make the second substrate 140 as close as possible to the device under test (or the conductive probes 110); thereby, the decoupling capacitor provided on the second substrate 140 It can be nearby to supplement the transient current of the power signal required by the DUT during high-frequency test.

As shown in FIG. 2, a plurality of wires 180 are disposed between the second substrate 140 and the conductive probes 110 to connect the output end of the circuit of the second substrate 140 to the conductive probes 110. . In order to achieve the above-mentioned feature "make the second substrate 140 as close as possible to the conductive probes 110", we can make the spatial distance between the conductive probes and the second substrate much smaller than the power transmission line 150 or the signal The length of the transmission line 160. In this embodiment, the lengths of the wires 180 are less than or equal to a quarter of the length of the power transmission line 150 or the signal transmission line 160. The above-mentioned quarter ratio is an exemplary embodiment for teaching. This limits the scope of the invention. In this way, the decoupling capacitor with the above characteristics can be achieved to supplement the transient current required by the DUT during high-frequency testing nearby. In addition, in order to ensure the signal integrity of the electrical test of the device under test at high frequency, the signal transmission line 160 can be a coaxial cable; on the other hand, to ensure the power supply of the electrical test of the device under test at high frequency is complete Degree, the power transmission line 150 can use twisted pair, and it will not interfere with it. His power or signal channel.

As described above, the circuit on the second substrate 140 includes at least one decoupling capacitor, and the possible embodiments are described below. FIG. 3 is a circuit diagram of the second substrate 140 circuit 145 of the first example. As shown, the conductive probes 110 include a first probe 111, a second probe 112, a third probe 113, and a fourth probe 114. The power transmission line 150 includes a first transmission line 151 and a second transmission line 152. The signal transmission line 160 includes a third transmission line 161 and a fourth transmission line 162. The layout of the circuit 145 will make the first transmission line 151 connected to the first probe 111, and the second transmission line 152 connected to the fourth probe 114, The third transmission line 161 is connected to the second probe 112 and the fourth transmission line 162 is connected to the third probe 113. In addition, the circuit 145 includes a matching circuit composed of a decoupling capacitor Cdc and a resistor; the decoupling capacitor Cdc is connected to the first probe 111 and the fourth probe 114 to supplement the nearby device under test at high frequency. Required transient current. The matching circuit includes a resistor R1 connecting the third transmission line 161 and the second probe 112, a resistor R2 connecting the fourth transmission line 162 and the third probe 113, and a resistor R2 connecting the third transmission line 161 and The resistance R3 of the fourth transmission line 162 can reduce the signal reflection of the signal transmission line 160 during the high-frequency test due to the attenuation effect of the resistance on the signal.

FIG. 4 is a circuit diagram of the second substrate 140 circuit 146 of the second example. As shown, the conductive probes 110 include a first probe 111, a plurality of second probes 112, a plurality of third probes 113, and a fourth probe 114. The power transmission line 150 includes a first transmission line 151 and The second transmission line 152. The signal transmission line 160 includes a third transmission line 161 and a fourth transmission line 162. The layout of the circuit 146 will make the first transmission line 151 connect to the first probe 111 and the second transmission line 152 connect to the fourth The probe 114, the third transmission line 161 are connected to the second probes 112, and the fourth transmission line 162 is connected to the third probes 113. The circuit 146 includes a matching circuit composed of a decoupling capacitor Cdc and a resistor. The decoupling capacitor Cdc is connected to the first probe 111 and the fourth probe 114 to supplement the nearby device under test during high-frequency testing. Required transient current. The matching circuit includes: a plurality of resistors R1, a plurality of resistors R2, and a resistor R3; wherein the resistors R1 are respectively connected to the third transmission line 161 and the corresponding second probe 112, and the resistors R2 are respectively connected to the first Four transmission lines 162 and the corresponding third The probe 113 is connected to the third transmission line 161 and the fourth transmission line 162 with the resistor R3. That is, this embodiment is suitable for a test pad having a plurality of signal inputs for the component under test; in addition, the signal attenuation of the signal transmission line 160 during high-frequency testing can be reduced by the attenuation effect of the resistor on the signal.

FIG. 5 is a circuit diagram of the second substrate 140 circuit 147 of the third example. As shown in the figure, the circuit 147 of this embodiment is basically the same as the second example. The difference is that the circuit 147 further includes a power regulator 170, which is disposed on the first transmission line 151 and the first probe. Between pins 111, it can be used to enhance the transient current required by the DUT during high-frequency testing, and to isolate the external power source from interference with the power signal of the second example.

The above are only preferred embodiments of the present invention, and should not be used to limit the scope of the present invention. That is to say, all equal changes and modifications made in accordance with the scope of the patent application of the present invention will still not lose the essence of the present invention, nor deviate from the spirit and scope of the present invention, so they should be regarded as the further implementation status of the present invention.

100‧‧‧ Probe Card

110‧‧‧Conductive probe

120‧‧‧First substrate

130‧‧‧ Probe Holder

140‧‧‧second substrate

150‧‧‧ Power Transmission Line

160‧‧‧Signal transmission line

180‧‧‧Wire

Claims (5)

A probe card includes: a plurality of conductive probes; a first substrate; a probe fixing base disposed on the first substrate and used to fix the conductive probes; a second substrate including a connection to the Circuits such as conductive probes; a power transmission line and a signal transmission line connecting the first substrate and the circuit; and a plurality of wires used to connect the circuit and the conductive probes, the length of which is shorter than the power transmission line or the signal Quarter length of transmission line. The probe card according to item 1 of the scope of patent application, wherein the power transmission line is a pair of twisted pairs, and the signal transmission line is a coaxial cable. The probe card according to item 1 of the patent application scope, wherein the conductive probes include a first probe, a second probe, a third probe, and a fourth probe, and the power transmission line includes a first transmission line and The second transmission line includes a third transmission line and a fourth transmission line. The circuit enables the first transmission line to be connected to the first probe, the second transmission line to be connected to the fourth probe, and the third transmission line to be connected to the second probe. The pin and the fourth transmission line are connected to the third probe, and the circuit includes: a decoupling capacitor connecting the first probe and the fourth probe; and a connection between the third transmission line and the second probe. A first resistor; a second resistor connecting the fourth transmission line and the third probe; and a third resistor connecting the third transmission line and the fourth transmission line. The probe card according to item 1 of the patent application scope, wherein the conductive probes include a first probe, a plurality of second probes, a plurality of third probes, and a fourth probe, and the power transmission line includes A first transmission line and a second transmission line, the signal transmission line includes a third transmission line and a fourth transmission line, and the circuit enables the first transmission line to be connected to the first probe, the second transmission line to be connected to the fourth probe, and the third transmission line The second probes and the fourth transmission line are connected to the third probes, and the circuit includes: a decoupling capacitor connecting the first probe and the fourth probe; and a plurality of first resistors, respectively Connect the third transmission line with the corresponding second probe; a plurality of second resistors are connected to the fourth transmission line A transmission line and the corresponding third probe; and a third resistor connecting the third transmission line and the fourth transmission line. The probe card according to item 4 of the scope of patent application, wherein the circuit further includes: a power conditioner connecting the first transmission line and the first probe.