JP2020128881A - Short circuit inspection system, and short circuit inspection method - Google Patents

Abstract

To provide a short circuit inspection system and a short circuit inspection method, which are capable of easily inspecting an inspection object including a plurality of wirings and a conductive portion which electrically connects one ends of the respective wirings.SOLUTION: A short circuit inspection device 1 is the short circuit inspection device 1 for inspecting an inspection object A including four or more wirings L and a conductive layer 102 for electrically connecting one end of each wiring L to each other. The short circuit inspection device includes: a current supply unit 3 that causes current I to flow between pads P1 and P2 of a pair of first wirings G1 among the four or more wirings L; a voltage detection unit 4 for detecting the voltage V between pads P3 and P4 of a pair of second wirings G2 including a wiring L different from the pair of first wirings and adjacent to at least one of the pair of first wirings G1; and an inspection processing unit 52 that determines a defect if the voltage V detected by the voltage detection unit 4 is not substantially zero.SELECTED DRAWING: Figure 1

Description

The present invention relates to a short circuit inspection system and a short circuit inspection method for inspecting a short circuit between wirings.

2. Description of the Related Art Conventionally, there is known an inspection method for inspecting the presence or absence of a short circuit defect between a plurality of wirings that are led out from a trunk wiring in a branch shape (see, for example, Patent Document 1).

The inspection method described in Patent Document 1 inspects a circuit wiring including a trunk wiring and a plurality of branch wirings branched from the trunk wiring, and two lands are provided in each of the branch wirings. The presence or absence of a disconnection between the two lands of each of the branch wirings, between two lands on one branch wiring side of two adjacent branch wirings, and between two lands on the other branch wiring side. In a circuit wiring inspection method for inspecting each for the presence or absence of a short circuit between them, an inspection signal generation means including a signal output detection portion and an inspection signal detection means are provided, and the inspection signal generation means is provided on the one branch wiring side. The test signal detecting means is connected between the two lands on the side of the other branch wiring, and the signal output detecting section connects the test signal generating means to the one of the one side. When the inspection signal supplied between the two lands on the side of the branch wiring is not detected, it is determined that there is a disconnection between the two lands on the side of the one branch wiring, and the inspection signal detecting means detects the 2 on the side of the other branch wiring. When the inspection signal is detected between two lands, it is determined that there is a short circuit between the two lands on the other branch wiring side and the two lands on the one branch wiring side.

Japanese Patent Laid-Open No. 2005-300240

Conventionally, a flip-chip CSP (Chip Size Package) has been used as a method for performing fan-out wiring from an IC die, and in recent years, a fan-out wafer level package (FOWLP) has become mainstream. .. The fan-out wafer level package manufacturing method includes a chip first method and a chip last method, and the chip first method was initially used.

In the chip-first method, a redistribution wiring layer (RDL: Redistribution Layer) is stacked on a non-defective IC die. Therefore, when a defect occurs in the redistribution wiring layer, the non-defective IC die is defective. Therefore, the amount of damage when a defect occurs becomes large, and it is difficult to improve productivity.

Therefore, the chip last method of mounting the IC die after confirming that the rearrangement wiring layer is a good product is drawing attention. In the chip last method, first, a conductive layer 102 made of copper or the like is formed on the surface of an insulating substrate 101 such as a glass substrate to make a carrier 100 (FIG. 8A).

Next, the rearrangement wiring layer 103 is formed on the conductive layer 102 of the carrier 100 by a plating process or the like (FIG. 8B). In the rearrangement wiring layer 103, a plurality of wirings L1 to L8 penetrating the rearrangement wiring layer 103 are formed (the wirings L1 to L4 are not shown). One end of each of the wirings L1 to L8 is connected to the conductive layer 102. One end of each of the wirings L1 to L8 is exposed by peeling the carrier 100 in a later step, for example, a board mounting step, and becomes an external terminal of the semiconductor device. The other ends of the wirings L1 to L8 are exposed on the upper surface of the rearrangement wiring layer 103 and serve as pads P1 to P8.

8B and 8C show cross sections taken at the positions of the pads P5 to P8. Hereinafter, the wirings L1 to L8 are collectively referred to as the wiring L, and the pads P1 to P8 are collectively referred to as the pad P.

Next, the IC die 106 is mounted on the upper surface of the rearrangement wiring layer 103 (FIG. 8C). The pad P is connected to the terminal on the lower surface of the IC die 106.

As described above, in the chip last method, the IC die 106 is mounted after confirming that the rearrangement wiring layer 103 is a good product. Therefore, it is necessary to perform the inspection at the stage of FIG. 8B before the IC die 106 is mounted. Here, in the stage of FIG. 8B, the inspection object A in which the rearranged wiring layer 103 is formed on the carrier 100 includes a plurality of wirings L and a conductive layer 102 that electrically connects one ends of the wirings L to each other. Thus, the plurality of wirings L are drawn out from the conductive layer 102 in a branch shape.

It is necessary to perform a short-circuit inspection whether or not a short circuit has occurred between the plurality of wiring lines L. However, the inspection method described in the above-mentioned Patent Document 1 can be inspected only by circuit wiring in which two lands are provided in each branch wiring, whereas the inspection object A The exposed portion is only the pad P. Therefore, the inspection method described in Patent Document 1 described above cannot inspect the inspection target A.

An object of the present invention is to provide a short-circuit inspection system and a short-circuit inspection method, which are capable of easily inspecting an inspection object including a plurality of wirings and a conductive portion that electrically connects one ends of the wirings to each other.

A short-circuit inspection system according to an example of the present invention is a short-circuit inspection system for inspecting an inspection object including four or more wirings and a conductive portion that electrically connects one ends of the wirings to each other. A current supply unit that causes a current to flow between the other end and the other end of the pair of first wirings among the plurality of wirings, and a wiring different from the pair of first wirings. A voltage detection unit that detects a voltage between one end and the other end of the pair of second wirings including a wiring adjacent to at least one of the first wirings, and the voltage detection unit detects the voltage. An inspection processing unit that determines a defect when the applied voltage is not substantially zero.

A short-circuit inspection method according to an example of the present invention is a short-circuit inspection method for inspecting an inspection object including four or more wirings and a conductive portion that electrically connects one end of each wiring to each other, Of the four or more wirings, a current supply step of flowing a current between the other end and the other end of the pair of first wirings is a wiring different from the pair of wirings. A voltage detection step of detecting a voltage between one end and the other end of the pair of second wirings including a wiring adjacent to at least one of the first wirings, and detected by the voltage detection step. And an inspection step of determining that the voltage is defective when the applied voltage is not substantially zero.

With the short-circuit inspection system and the short-circuit inspection method having such a configuration, it is easy to inspect an inspection object including a plurality of wirings and a conductive portion that electrically connects one ends of the wirings to each other.

It is a block diagram which shows an example of a structure of the short circuit inspection device which uses the short circuit inspection method which concerns on one Embodiment of this invention. It is a flow chart which shows an example of operation of a short circuit inspection method and a short circuit inspection device concerning one embodiment of the present invention. It is explanatory drawing which shows an example of arrangement|positioning of a pad. It is explanatory drawing which shows another example of arrangement|positioning of a pad. It is explanatory drawing which shows the electric current path at the time of normal. It is explanatory drawing which shows the electric current path at the time of the short circuit defect being produced. FIG. 7 is an equivalent circuit diagram of FIG. 6. It is explanatory drawing for demonstrating the chip last construction method of a fan-out wafer level package.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. It should be noted that in each of the drawings, the components denoted by the same reference numerals indicate the same components, and the description thereof will be omitted. With reference to FIG. 1 and FIG. 8, a short circuit inspection apparatus 1 which is an example of a short circuit inspection system includes a plurality of probes Pr, a scanner unit 2, a current supply unit 3, a voltage detection unit 4, and a control unit 5. ..

FIG. 8B shows an example in which the inspection object A includes eight wirings L and eight pads P, but the short-circuit inspection apparatus 1 includes four or more wirings L and four wirings L. It is possible to inspect the inspection object A including the above-mentioned pad P.

The inspection target is not limited to the one in which the rearrangement wiring layer is formed on the carrier for the chip last process in the fan-out wafer level package. For example, as a method of manufacturing a board, a conductive metal plate is used as a base to form printed wiring boards on both sides of the metal plate, and the formed board is peeled from the base metal plate to form two printed wiring boards. There is a method of forming a substrate. In such a substrate manufacturing method, the substrate (hereinafter referred to as an intermediate substrate) in a state before the substrate is separated from the base metal plate has a mode in which the metal plate is sandwiched between two substrates. .. Such an intermediate substrate is also called a carrier substrate. The intermediate substrate may also have a configuration in which one ends of the plurality of wirings are electrically connected to each other by the metal plate (conductive portion). Such an intermediate substrate may be an inspection target.

Further, there is a multilayer substrate having a conductor pattern that spreads in a planar shape in an inner layer of the substrate, and one end of a plurality of wirings is electrically connected to each other by the conductor pattern (conductive portion). Such a multilayer substrate may be an inspection target.

The plurality of probes Pr come into contact with the plurality of pads P (other ends) provided on the inspection object A, respectively. The current supply unit 3 is a so-called constant current power supply circuit. The current supply unit 3 supplies a current I to the inspection object A via the scanner unit 2 and the probe Pr in response to a control signal from the control unit 5. The voltage detection unit 4 is a voltage detection circuit that detects the voltage of the inspection object A via the probe Pr and the scanner unit 2 and transmits the voltage value to the control unit 5.

The scanner unit 2 is a switching circuit configured by using switching elements such as transistors and relay switches. The scanner unit 2 has current terminals +F and −F for supplying a current I to the inspection object A and a voltage detection terminal for detecting a voltage generated between the pair of pads P of the inspection object A by the current I. It has +S, -S. A plurality of probes Pr are electrically connected to the scanner unit 2. The scanner unit 2 switches the connection relationship between the current terminals +F and −F and the voltage detection terminals +S and −S and the plurality of probes Pr according to the control signal from the control unit 5.

The current supply unit 3 has its output terminal, the positive electrode side being connected to the current terminal +F, and the negative electrode side being connected to the current terminal -F. The voltage detection unit 4 has one end connected to the voltage detection terminal +S and the other end connected to the voltage detection terminal -S.

Then, the scanner unit 2 can connect the current terminals +F and −F and the voltage detection terminals +S and −S to the arbitrary probe Pr in accordance with the control signal from the control unit 5. As a result, the current supply unit 3 causes a current to flow between the pad P and the pad P of the wiring L that is the pair of first wirings selected according to the control signal from the control unit 5. In addition, the voltage detection unit 4 is a wiring L selected according to a control signal from the control unit 5 and different from the pair of first wirings, and is adjacent to at least one of the pair of first wirings. The voltage between the pad P and the pad P of the pair of second wirings including the wiring L is detected.

The control unit 5 is configured using, for example, a microcomputer. The control unit 5 includes a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a RAM (Random Access Memory) that temporarily stores data, a storage unit 53 such as a nonvolatile hard disk drive or a flash memory, and these. It is equipped with peripheral circuits. Then, the control unit 5 functions as the wiring selection unit 51 and the inspection processing unit 52, for example, by executing a control program stored in advance in the storage unit 53.

In addition, wiring information indicating the wiring structure of the rearrangement wiring layer 103 is stored in the storage unit 53 in advance. The wiring information is information indicating the arrangement of the plurality of wirings L and pads P in the rearrangement wiring layer 103. As the wiring information, for example, Gerber data used for manufacturing the rearranged wiring layer 103 can be used.

The wiring selection unit 51 selects a pair of wirings L as a first wiring and a pair of wirings L different from the first wiring as a second wiring based on the wiring information. When selecting the wiring L as the first wiring and the second wiring, the wiring selection unit 51 uses a combination in which at least one of the pair of first wirings and at least one of the pair of second wirings are adjacent to each other. Select the wiring L.

The wiring selection unit 51 is not limited to the example provided in the short circuit inspection device 1. For example, the wiring selection unit 51 may be configured as a device different from the short circuit inspection device 1 by causing a computer different from the short circuit inspection device 1 to function as the wiring selection unit 51. Then, the computer configured as the wiring selection unit 51 selects the pair of first wirings and the pair of second wirings based on the wiring information, and the pair of first wirings and the pair of first wirings thus obtained are selected. Information indicating the two wirings may be stored in the storage unit 53. As described above, the computer configured as the wiring selection unit 51 and the short-circuit inspection device 1 that does not include the wiring selection unit 51 may form a short-circuit inspection system.

A known method can be used as a method of selecting the wirings L adjacent to each other in order to select the first wiring and the second wiring, and for example, PC-Auto CAM manufactured by Dynatron can be used.

Further, only the short circuit inspection device 1 that does not include the wiring selection unit 51 may be the short circuit inspection system. The pair of first wirings and the pair of second wirings do not necessarily have to be selected by the wiring selection unit 51. For example, an operator selects the pair of first wirings and the pair of second wirings, and the short circuit inspection device 1 It may be stored in the storage unit 53.

The inspection processing unit 52 controls the scanner unit 2 based on the first and second wirings selected by the wiring selection unit 51 or stored in the storage unit 53, and the current supply unit 3 supplies a current to the pair of first wirings. Is supplied, and the voltage detection unit 4 detects the voltage between the pair of second wirings.

Then, the inspection processing unit 52 determines that there is a defect when the voltage detected by the voltage detection unit 4 is not substantially zero.

Next, the operation of the short circuit inspection method and the short circuit inspection apparatus 1 according to the embodiment of the present invention will be described. With reference to FIGS. 2 to 4, first, the wiring selection unit 51 refers to the wiring information, and one of the pair of first wirings and one of the pair of second wirings are adjacent to each other, and The combination of the wiring L in which another one of the first wirings and the other one of the pair of second wirings are adjacent to each other is searched (step S1).

Here, when the two wirings L are adjacent to each other and when the two wirings L are greatly separated, it is considered that a defect such as short-circuiting of the two wirings L is unlikely to occur. Therefore, the distance of the wiring L, which is likely to cause a short circuit failure, is set in advance as a set distance. Then, in step S1, the wiring selection unit 51 determines that one of the pair of first wirings and one of the pair of second wirings are adjacent to each other within the range of the set distance, and the other of the pair of first wirings. It is more preferable to search for a combination of the adjacent wirings L within the range of the set distance between the one wiring and the other one of the pair of second wirings.

FIGS. 3 and 4 show the arrangement of the pads P1 to P8 as viewed from the upper surface side of the rearrangement wiring layer 103 shown in FIG. 8B. The wirings L connected to the pads P adjacent to each other are adjacent to each other. In the example shown in FIG. 3, the wirings L1 and L2 connected to the pads P1 and P2 are the first wiring G1, and the wirings L5 and L6 connected to the pads P5 and P6 are the second wiring G2. The wiring L1 is adjacent to the wiring L5 of the pair of second wirings G2, and the wiring L2 of the pair of first wirings G1 is adjacent to the wiring L6 of the pair of second wirings G2.

When such a combination is found (YES in step S2), the wiring selection unit 51 selects the pair of first wirings G1 and the pair of second wirings G2 in the found combination (step S4). When the wiring L is arranged as shown in FIG. 3, the wiring selection unit 51 sets the wirings L1 and L2 as the first wiring G1 and the wirings L5 and L6 as the second wiring G2.

On the other hand, for example, when the wirings L1 to L8 are arranged in a line as shown in FIG. 4, there is no combination of the wirings L searched in step S1. Therefore, when there is no combination searched in step S1 (NO in step S2), the wiring selection unit 51 refers to the wiring information and selects one of the pair of first wirings and the pair of second wirings. A combination of wirings L adjacent to each other is searched (step S3).

In step S3 as well, as in the case of step S1, the wiring selection unit 51 causes the wiring L in which one of the pair of first wirings and one of the pair of second wirings are adjacent to each other within the set distance range. More preferred is to search for a combination of

In the example shown in FIG. 4, the wirings L1 and L2 connected to the pads P1 and P2 are the first wiring G1, and the wirings L3 and L4 connected to the pads P3 and P4 are the second wiring G2. The wiring L2 and the wiring L3 of the pair of second wirings G2 are adjacent to each other.

Next, the inspection processing unit 52 causes the scanner unit 2 to connect the current supply unit 3 to the pair of first wirings based on the pair of first wirings G1 and the pair of second wirings G2 selected by the wiring selection unit 51. The voltage detection unit 4 is connected to the pad P of the wiring, and the voltage detection unit 4 is connected to the pad P of the pair of second wirings (step S5).

Next, the inspection processing unit 52 causes the voltage supply unit 3 to cause the current I to flow through the pair of first wirings, and causes the voltage detection unit 4 to detect the voltage V between the pads P of the pair of second wirings (step S6). ).

Step S3, as shown in FIG. 4, when the wirings L1 and L2 are the first wirings G1 and the wirings L3 and L4 are the second wirings G2, as shown in FIG. 5, from the pad P2 to the wiring L2, the conductive layer 102, A current I flows through a path reaching the pad P1 via the wiring L1. In addition, since no current flows in the path between the pads P3 and P4 whose voltage is measured by the voltage detection unit 4, the current flowing through the loop circuit to be measured by the voltage detection unit 4 is zero. Therefore, if the resistance value of the path between the pads P3 and P4 is Rs, the voltage V=0×Rs=0. That is, when there is no short circuit defect between the first wiring G1 and the second wiring G2, the voltage V detected by the voltage detection unit 4 becomes zero.

Therefore, the inspection processing unit 52 compares the voltage V with zero (step S7), and when the voltage V is substantially zero (YES in step S7), the adjacent first wiring G1 and second wiring G2 are connected. During this period, it is determined that there is no short circuit (step S8), and the process ends.

It should be noted that “substantially zero” means that the voltage generated by the detection error of the voltage detection unit 4, the leakage current within the normal range in the inspection object A, and the like is regarded as zero.

On the other hand, when a short circuit defect has occurred between the first wiring G1 and the second wiring G2, the following occurs. For example, as shown in FIG. 6, when a short-circuited portion Re occurs between the wiring L2 and the wiring L3, the current I flowing through the wiring L2 is a branch point with the short-circuited portion Re and the current I1 flowing through the wiring L2 as it is. And the current I2 flowing through the short circuit portion Re. The current I2 joins the current I1 via the wiring L3 and the conductive layer 102.

In FIG. 7, the wiring L1 is the resistance R1, the pad P2 side is the resistance R21 from the short circuit portion Re of the wiring L2, the conductive layer 102 side is the resistance R22 from the short circuit portion Re of the wiring L2, and the pad P3 side is the short circuit portion Re from the wiring L3. A resistor R31, a resistor R32 on the conductive layer 102 side of the short circuit portion Re of the wiring L3, a resistor R4 on the wiring L4, a resistor Rc1 on the conductive layer 102 between the wirings L1 and L2, a resistor Rc2 on the conductive layer 102 between the wirings L2 and L3, The conductive layer 102 between the wirings L3 and L4 is represented by a resistor Rc3.

As shown in FIG. 7, the current I2 flows through the short circuit portion Re, the resistor R32, and the resistor Rc2. On the other hand, the voltage detector 4 detects the voltage across the series circuit of the resistors R31, R32, Rc3, R4 as the voltage V. Then, the voltage V does not become substantially zero, and the voltage detection unit 4 detects the voltage of the resistance value B×I2 of the resistor R32 as the voltage V.

Therefore, when the voltage V is not substantially zero (NO in step S7), the inspection processing unit 52 determines that there is a short circuit between the adjacent first wiring G1 and second wiring G2 (step S9). , The process ends.

FIG. 7 illustrates the case where the wirings L1 and L2 are the first wiring G1 and the wirings L3 and L4 are the second wiring G2 in the example where the pads P1 to P8 are arranged in a line (FIG. 4) (step S3). In the example in which the columns of P1 to P4 and the columns of pads P5 to P8 are arranged in parallel (FIG. 3), the wirings L1 and L2 are the first wirings G1 and the wirings L5 and L6 are the second wirings G2 (step S1). Even if there is, a short circuit defect between the first wiring G1 and the second wiring G2 can be inspected. In this case, the respective wirings L are arranged as indicated by the reference numerals in parentheses in FIG. 5, and like the above-mentioned short circuit Re between the wirings L2 and L3, the wirings L2 and L6 are arranged between them. When a short circuit failure occurs, the voltage V becomes substantially non-zero in step S7, so that the short circuit failure can be determined.

In this case, the wirings L2 and L6 are adjacent to each other, and the wirings L1 and L5 are adjacent to each other. Therefore, even if a short circuit failure occurs between the wirings L1 and L5, the voltage V is not substantially zero in step S7. As a result, it becomes possible to inspect for a short circuit defect between the wirings L2 and L6 and a short circuit defect between the wirings L1 and L5 at one time.

Therefore, one of the pair of first wirings and one of the pair of second wirings are adjacent to each other, and one of the pair of first wirings and the other of the pair of second wirings are adjacent to each other. Is a combination of wirings L adjacent to each other (step S1, FIG. 3) is a combination of wirings L where one of the pair of first wirings and one of the pair of second wirings are adjacent (step S3, FIG. 4). Inspection efficiency is higher than.

That is, according to the processes of steps S1 to S9, it is easy to inspect the inspection target A including the plurality of wirings L and the conductive layer 102 that electrically connects one ends of the wirings L to each other. Further, the step S1 is executed first to preferentially search for a combination of the wirings L having a high inspection efficiency, and if such a combination is not found, the step S3 is executed, so that the inspection efficiency of the inspection object A is improved. Can be improved.

The steps S1 and S2 may not be executed.

By the way, when the wirings L2 and L3 are short-circuited by the short circuit portion Re as shown in FIG. 6, the resistance value between the pads P2 and P3 is reduced. Therefore, an inspection method is conceivable in which the resistance value between the pads P2 and P3 is measured and it is determined that there is a short circuit failure when the resistance value becomes smaller than a normal value.

However, the wirings L2 and L3 and the conductive layer 102 have extremely low resistance. Therefore, the resistance decrease due to the short circuit portion Re is slight. As a result, extremely high-precision resistance measurement is required to perform such inspection.

A four-terminal resistance measuring method is known as such a highly accurate resistance measuring method. In the four-terminal resistance measuring method, it is necessary to bring two probes into contact with one pad P. However, in the inspection object A for the fan-out wafer level package in which the rearrangement wiring layer 103 is laminated on the carrier 100, the pad P is extremely small because it is directly connected to the IC die, and two pads P are provided. It is difficult to bring the probe into contact.

On the other hand, according to the short-circuit inspection device 1, since it is only necessary to bring one probe into contact with one pad P, it is possible to easily inspect the inspection object A as compared with the case of using the four-terminal resistance measuring method.

Further, as described above, in the case of inspecting for a short circuit failure based on a minute decrease in resistance due to the short circuit portion Re, it is necessary to use a resistance value of a non-defective product as a reference value and determine a minute decrease in resistance from the reference value. However, as described above, the wiring L of the rearrangement wiring layer 103 in the fan-out wafer level package is formed by the plating process or the like.

However, since the plating process has a large variation, the variation in the resistance value of the non-defective wiring L is large, and the variation in the resistance of the non-defective article easily exceeds the resistance reduction due to the short circuit portion Re. Therefore, it is not possible to set a reference value as a determination reference, and it is difficult to inspect for a short circuit failure due to resistance decrease.

On the other hand, according to the short-circuit inspection apparatus 1, it is not necessary to set the reference value only by determining whether or not the voltage V is substantially zero (step S7), so that a short circuit occurs even if the resistance variation of the wiring L is large. It is easy to inspect for defects.

That is, the short-circuit inspection system according to an example of the present invention is a short-circuit inspection system for inspecting an inspection object including four or more wirings and a conductive portion that electrically connects one ends of the respective wirings to each other, Of the four or more wirings, a current supply unit that causes a current to flow between the other end and the other end of the pair of first wirings, and the pair of first wirings are different wirings, A voltage detection unit that detects a voltage between one end and the other end of a pair of second wirings including a wiring adjacent to at least one of the pair of first wirings, and the voltage detection unit. An inspection processing unit that determines that the voltage is defective when the voltage detected by is not substantially zero.

A short-circuit inspection method according to an example of the present invention is a short-circuit inspection method for inspecting an inspection object including four or more wirings and a conductive portion that electrically connects one end of each wiring to each other, Of the four or more wirings, a current supply step of flowing a current between the other end and the other end of the pair of first wirings is a wiring different from the pair of wirings. A voltage detection step of detecting a voltage between one end and the other end of the pair of second wirings including a wiring adjacent to at least one of the first wirings, and detected by the voltage detection step. And an inspection step of determining that the voltage is defective when the applied voltage is not substantially zero.

According to these configurations, when there is no short circuit defect between the pair of first wirings and the pair of second wirings, the current supplied to the pair of first wirings flows to the pair of second wirings. Absent. Therefore, since no voltage is generated in the pair of second wirings, the voltage detected between one end and the other end of the pair of second wirings is substantially zero. On the other hand, when there is a short circuit failure between the pair of first wirings and the pair of second wirings, a part of the current supplied to the pair of first wirings is the second wiring adjacent to the pair of first wirings via the short circuit failure. Wrap around. The sneak current flows into the second wiring to generate a voltage, and the voltage detected between the other end of one of the pair of second wires is not substantially zero. As a result, if the detected voltage is not substantially zero, it can be determined as defective. Therefore, it is easy to inspect an inspection object including a plurality of wirings and a conductive portion that electrically connects one end of each wiring.

In addition, one of the pair of first wirings and one of the pair of second wirings are adjacent to each other, and another one of the pair of first wirings and another of the pair of second wirings are adjacent to each other. It is preferable that one of the two is adjacent.

According to this configuration, a short-circuit defect between one of the adjacent first wirings and one of the second wirings and another one of the adjacent first wirings and the second wiring can be performed in one inspection. It can be inspected for a short circuit with another one. Therefore, the inspection efficiency is improved.

Further, it is preferable to further include a wiring selection unit that selects the pair of first wirings and the pair of second wirings from the four or more wirings.

According to this configuration, the wiring selection unit selects the pair of first wirings to which the current supply unit supplies the current and the pair of second wirings to which the voltage detection unit detects the voltage.

Further, the wiring selection unit, as the pair of first wirings and the pair of second wirings, one of the pair of first wirings and one of the pair of second wirings are adjacent to each other, It is preferable to preferentially select a combination of the wirings in which another one of the pair of first wirings and another one of the pair of second wirings are adjacent to each other.

According to this configuration, a short-circuit defect between one of the adjacent first wirings and one of the second wirings and another one of the adjacent first wirings and the second wiring can be performed in one inspection. Since a wiring combination having a high inspection efficiency capable of inspecting for a short circuit with another wiring is preferentially selected, it is possible to improve the inspection efficiency.

Further, the inspection object is a fanout wafer level package in which a rearrangement wiring layer is formed on a carrier, each of the wirings is a wiring of the rearrangement wiring layer, and the conductive portion is the carrier. It may be a conductor layer on the surface of.

With this configuration, it is possible to inspect a short circuit defect between the wirings formed in the rearranged wiring layer of the fan-out wafer level package.

1 Short-circuit inspection device (short-circuit inspection system)
2 Scanner Section 3 Current Supply Section 4 Voltage Detection Section 5 Control Section 51 Wiring Selection Section 52 Inspection Processing Section 53 Storage Section 100 Carrier 101 Insulating Substrate 102 Conductive Layer (Conductive Section)
103 relocation wiring layer 106 IC die A inspection object G1 first wiring G2 second wiring I, I1, I2 current L, L1 to L8 wiring P, P1 to P8 pad (other end)
Pr probe R1, R21, R22, R31, R32, R4, Rc1 to Rc3 resistance Re short circuit V voltage

Claims (6)

A short-circuit inspection system for inspecting an object to be inspected, comprising four or more wirings, and a conductive portion for electrically connecting one end of each wiring to each other,
Of the four or more wirings, a current supply unit that causes a current to flow between the other end and the other end of the pair of first wires,
A wire different from the pair of first wires, and one of the other end and the other end of the pair of second wires including a wire adjacent to at least one of the pair of first wires A voltage detection unit that detects the voltage between
A short-circuit inspection system comprising: an inspection processing unit that determines a defect when the voltage detected by the voltage detection unit is not substantially zero. One of the pair of first wirings is adjacent to one of the pair of second wirings, and another one of the pair of first wirings and another of the pair of second wirings are adjacent to each other. The short-circuit inspection system according to claim 1, wherein the book and the book are adjacent to each other. The short-circuit inspection system according to claim 1, further comprising a wiring selection unit that selects the pair of first wirings and the pair of second wirings from the four or more wirings. The wiring selecting unit, as the pair of first wirings and the pair of second wirings, one of the pair of first wirings and one of the pair of second wirings are adjacent to each other, and The short-circuit inspection system according to claim 3, wherein a combination of the wirings in which another one of the first wirings and another one of the pair of second wirings are adjacent to each other is preferentially selected. The object to be inspected is a fanout wafer level package in which a rearrangement wiring layer is formed on a carrier,
Each of the wiring is a wiring of the relocation wiring layer,
The short-circuit inspection system according to claim 1, wherein the conductive portion is a conductor layer on the surface of the carrier. A short-circuit inspection method for inspecting an inspection object comprising four or more wirings, and a conductive portion for electrically connecting one end of each wiring to each other,
Of the four or more wiring, a current supply step of flowing a current between the other end of one and the other end of the pair of first wiring,
Between the other end and the other end of the pair of second wires including a wire adjacent to at least one of the pair of first wires, which is a wire different from the pair of wires A voltage detection step of detecting the voltage,
A short-circuit inspection method comprising: an inspection step of determining a defect when the voltage detected by the voltage detection step is not substantially zero.

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