JP5817361B2 - Semiconductor element characteristic test apparatus and semiconductor element characteristic test method using the apparatus - Google Patents

Description

  The present invention is a semiconductor element having a resin sealing portion such as a TO3P type, and when conducting a conventional characteristic test for insulation inspection of a resin sealing portion of a semiconductor element in which a semiconductor chip is accommodated in the resin sealing portion. The present invention relates to a semiconductor element characteristic test apparatus that can be performed simultaneously and a characteristic test method including a dielectric strength test performed using the apparatus.

Semiconductor device characteristic tests include a leakage current characteristic test and a withstand voltage characteristic test, which are static characteristic tests, and an L load test and a switching test, which are dynamic characteristic tests.
FIGS. 11A and 11B are configuration diagrams of a full mold type IGBT 20, in which FIG. 11A is a front view and FIG. 11B is a side view. This IGBT (insulated gate bipolar transistor) is a full mold type IGBT 20 in which all of the upper surface, lower surface and side surfaces are sealed with resin. For example, it is a TO-3PF type resin molded product.

  A collector electrode (not shown) on the back surface 23 of the IGBT chip 22 is soldered on the die portion 21 which is a metal substrate, and a collector terminal 24a made of a lead frame is connected to the die portion 21. The emitter electrode 25 and the gate electrode pad 26 of the IGBT chip 22 are connected to an emitter terminal 24b and a gate terminal 24c made of a lead frame by bonding wires 27, respectively. The base part of the die part 21, the semiconductor chip 22, the bonding wire 27, and the terminals 24a, 24b, and 24c is resin-sealed to form a resin-sealed part 28. Each terminal 24 a, 24 b, 24 c is exposed from the resin sealing portion 28. Since this resin sealing is performed on all the upper, lower and side surfaces of the die portion, it is said to be a full mold type. The IGBT 20 is used with a cooling fin attached to the back surface 28 a of the resin sealing portion 28.

  FIG. 12 is a diagram for explaining the dielectric strength test of the resin sealing portion of the full mold type IGBT 20 shown in FIG. This insulation withstand test is performed on the assumption that a cooling fin (not shown) is installed and used in the resin sealing portion 28 on the back surface 23 side of the die portion 21 of the full mold type IGBT 20. This is performed in order to check the dielectric strength of the resin sealing portion 28.

  The dielectric strength test apparatus 500 includes an AC voltage application unit 71 and a voltage application jig 72 (here, an electrode is shown) that contacts the resin sealing unit 28 of the IGBT 20. The IGBT 20 is installed on the voltage application jig 72. The collector terminal 24a, the emitter terminal 24b, and the gate terminal 24c of the IGBT 20 are short-circuited to each other by the conductor 53, and a high voltage exceeding the AC voltage application unit 71 between the collector terminal 24a and the voltage application jig 72 (generally 2 kV or more). Is applied for a predetermined period (for example, about 1 minute), and it is determined whether or not the resin sealing portion 28 of the IGBT 20 breaks down.

The dielectric strength test in mass production will be described. Each terminal 24a, 24b, 24 of the full mold TO-3PF type IGBT 20 is short-circuited by the conductor 53 so as to be all at the same potential (in the figure, each terminal 24a, 24b, 24c is directly short-circuited by the conductor 53). However, the test probes connected to these terminals 24a, 24b, and 24 are actually short-circuited.
Then, the resin sealing part 28 is installed in the voltage application jig 72, and all the surfaces of the resin sealing part 28 are contacted. Thereafter, a high voltage is applied between the voltage application jig 72 and the collector terminal 24a for a predetermined time to measure the leakage current. The insulation failure of the resin sealing portion 28 is determined by detecting an abnormal increase in leakage current or a current value greater than a predetermined value. As described above, the dielectric strength test requires a power source and a voltage application jig (electrode) for applying a high voltage exceeding 1000 V (generally an AC voltage of 2 kV or more), and therefore only for performing a dielectric strength test. Test equipment is required.

  By the way, also when the bonding wire 27 connected to the terminals 24b and 24c is exposed from the front surface 28a of the resin sealing portion 28 of the IGBT 20, it is determined that the insulation is defective. This is because when the terminals 24a, 24b, and 24c are short-circuited by the conductor 53 and the collector terminal 24a and the bonding wire 27 are at the same potential, the voltage applying jig 72 and the bonding wire 27 come into contact with each other. This is because the voltage application jig 72 and the terminals 24a, 24b, and 24c are short-circuited through the wire.

  For example, even if the resin sealing portion 28 around the bonding wire 27 is covered in an unfilled state, if the distance T from the surface 28a of the resin sealing portion 28 is short, it is determined that the insulation is defective.

  As described above, when the dielectric strength test is performed on the front surface side of the resin sealing portion 28, it is necessary to provide a voltage application jig that matches the shape of the resin sealing portion, and only the dielectric strength test is performed. A dedicated test device is used.

  Next, FIG. 13 is a block diagram of a semi-molded TO-3P type IGBT with a cooling fin attached. FIG. 13 (a) is a front view, and FIG. The side view of each part before being performed, and FIG. 8C are back views of the IGBT itself. In the semi-molded TO-3P type IGBT 10, the back surface 11 a of the die portion 11 and the terminals 13 a, 13 b, and 13 c are exposed from the resin sealing portion 15.

  The difference from FIG. 11 is that many portions of the back surface 11 a of the die part 11 are exposed from the resin sealing part 15. A collector electrode (not shown) on the back surface of the IGBT chip 12 is joined to the die part 11 by solder (not shown). For this reason, as shown in FIG. 13, normally, when this type of IGBT 10 is used, the cooling fins 32 are connected to the back surface 11a of the die portion 11 with screws 33 and nuts 34 via an insulating plate 31 having a desired dielectric strength. It is fixed with. Therefore, the cooling fin 32 and the die part 11 are insulated from each other by an insulating plate 31 having a desired dielectric strength.

  Further, since the die part 11 of the IGBT 10 is exposed from the resin sealing part 15, the voltage application jig 72 is connected to the die part 11 even if the dielectric strength test is performed using the voltage application jig 72 shown in FIG. 12. The collector terminal 13a to which the voltage application jig 72 and the die part 11 are connected is in a short circuit state and voltage cannot be applied, and the dielectric strength test cannot be performed.

  Further, in the IGBT 10 having the TO-3P type resin sealing portion 15 of FIG. 13, the insulating plate 31 is attached to the back surface 11 a of the die portion 11, and the cooling fins 32 are fixed with screws through the insulating plate 31. Therefore, the dielectric strength between the bonding wire 14 and the surface 15a of the resin sealing portion 15 is not required.

In recent years, clip-type cooling fins 41 have been used in order to reduce the cost of the cooling fins 32 and to facilitate the mounting thereof.
14A and 14B are configuration diagrams of the IGBT 10 with the clip-type cooling fins 35 inserted therein. FIG. 14A is a front view and FIG. 14B is a side view.

  The front surface 15a of the resin sealing portion 15 of the IGBT 10 and the exposed back surface 11a of the die portion 11 are sandwiched between the clip-type cooling fins 35, and the heat generated in the IGBT chip 12 is dissipated from the clip-type cooling fins 35. Compared with the conventional cooling fin 32 of FIG. 13, the mounting is simple and the cooling fin 35 itself is extremely low cost.

  In Patent Document 1, a test voltage is applied between a lead connected to a metal wire (wire) in a resin mold and a sealing resin, and leakage current is detected to determine whether the sealing state is good or bad. Is disclosed.

JP 2004-271245 A

  However, the TO-3P type IGBT 10 with the clip-type cooling fin 35 shown in FIG. 14 has no sealing resin filling between the bonding wire 14 and the surface 15a of the resin sealing portion 15 as shown in FIG. When P is short, the sealing resin part 15 may cause dielectric breakdown during this period.

  If the dedicated dielectric strength test apparatus 500 is used to test the dielectric strength of the resin sealing portion 15 of the IGBT 10, the collector terminal 13a and the voltage application jig 72 are at the same potential, and a test voltage can be applied. Can not. Therefore, conventionally, the IGBT 10 having the TO-3P type resin sealing portion 15 has been shipped without performing an insulation resistance test.

  In addition, when the dielectric strength test is performed using the dedicated dielectric strength test apparatus 500 after insulating the back side 11a of the die portion 11 exposed from the resin sealing portion 15 with an insulating plate, the dielectric strength test is performed on the IGBT 10 as a test sample. Time required for installation in the apparatus 500 is required, and the test cost increases. In addition, when this dedicated dielectric strength test apparatus 500 is incorporated into an automatic test line, the area occupied by the automatic test line increases. Furthermore, it is necessary to obtain an expensive dedicated dielectric strength test apparatus 500.

  Further, in Patent Document 1, a test voltage for performing a normal characteristic test is applied between the lead terminal and the resin sealing portion, and a dielectric strength test of the resin sealing portion is simultaneously performed while performing the characteristic test. Is not described.

  The object of the present invention is to solve the above-mentioned problems, and in the semiconductor element in which the semiconductor chip is accommodated in the resin case, the dielectric strength test of the resin sealing portion and other characteristic tests can be simultaneously performed to reduce the test cost. Another object of the present invention is to provide a semiconductor element characteristic test apparatus capable of reducing the occupied area of the entire characteristic test apparatus and a semiconductor element characteristic test method using the apparatus.

In order to achieve the above object, according to the invention of claim 1, the semiconductor chip, the conductor to which the high potential electrode on the back surface of the semiconductor chip is connected, and the conductor are connected. A high potential terminal, a low potential terminal connected to the low potential side electrode of the semiconductor chip by a connection conductor, a control terminal connected to the control electrode of the semiconductor chip by a connection conductor, and a front surface of the conductor A semiconductor device characteristic test apparatus having the semiconductor chip and a resin sealing portion covering the connection conductor, wherein the test probe is in contact with each of the high potential terminal, the low potential terminal, and the control terminal. Voltage applying means for applying a predetermined voltage to each of the high potential terminal, the low potential terminal, and the control terminal via the test probe, and the high potential terminal and the low potential via the test probe. end , Detecting means for detecting at least one of voltage and current at each terminal of the control terminal, evaluation means for evaluating the characteristics of the semiconductor element from the detection result, and contacting the front surface of the resin sealing portion a test electrode, a connecting means for connecting the test electrode to a high potential terminal of the semiconductor element, wherein the high-potential terminal of the test probe, the low potential terminal, each terminal of the control terminal, wherein the test electrode is contacted to each of the resin sealing portion, a predetermined voltage is applied from the voltage applying means, said evaluating means evaluates at least one of the static characteristic or dynamic characteristic of said semiconductor device based on the detected value with A semiconductor device characteristic test apparatus for evaluating the dielectric strength of the resin-encapsulated portion .

According to the invention described in claim 2 of the claims, in the invention described in claim 1, the connection means connects the test electrode and the test probe contacting the high potential terminal. It is good that it is a conducting wire.

According to the invention described in claim 3 of the claims, in the invention described in claim 1, the connection means may be configured to bring the test electrode into direct contact with the conductor.
According to the invention described in claim 4 of the claims, in the invention described in any one of claims 1 to 3, the test electrode may be supported by an elastic body.

According to the invention described in claim 5 of the claims, in the invention described in claim 1, the semiconductor element is elastic from the front surface side of the resin sealing portion and the back surface side of the conductor. wherein the conductive clip electrodes sandwiching a manner attached to the semiconductor element, the clip electrodes alternate then good to said test electrode and said connecting means.

  According to the invention described in claim 6 of the claims, in the invention described in claim 1, the static characteristic test is at least one of a leakage current characteristic test and a withstand voltage characteristic test. The test may be an L load tolerance test.

According to the seventh aspect of the present invention, the semiconductor element characteristic test performed using the semiconductor element characteristic test apparatus according to any one of the first to sixth aspects. In the method, at least one of a static characteristic test and a dynamic characteristic test of the semiconductor element is applied simultaneously with at least one of the rated voltage of the semiconductor element between the high potential electrode and the low potential side electrode to insulate the resin sealing portion. A semiconductor device characteristic test method for performing a tolerance test.

According to this invention, the dielectric strength test of the resin sealing portion can be performed using a characteristic test apparatus such as a leakage current test, a withstand voltage characteristic test, and an L load test.
Even a semiconductor element in which the back surface of the die portion is exposed from the resin sealing portion can be subjected to the dielectric strength test of the resin sealing portion.

  Since the dielectric strength test of the resin sealing portion can be simultaneously performed using the characteristic test apparatus, the test cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a principal part block diagram of the semiconductor element characteristic test apparatus 100 of 1st Example of this invention, (a) is a principal part side view, (b) is a principal part top view which looked at (a) from the arrow A. is there. It is principal part sectional drawing of the characteristic test apparatus 100 of this invention, (a) is a state figure before a test, (b) is a state figure under a test. It is a test process figure of the characteristic test method of the semiconductor element of 2nd Example of this invention. FIG. 4 is a test process diagram of the semiconductor device characteristic test method according to the second embodiment of the present invention continued from FIG. 3; FIG. 5 is a test process diagram of the semiconductor device characteristic test method according to the second embodiment of the present invention continued from FIG. 4; It is an applied voltage waveform figure when performing a leakage current characteristic test using the leakage current characteristic test apparatus 100a of this invention. It is a principal part block diagram of the L load characteristic test apparatus 100b which is one of the characteristic test apparatuses 100 of this invention. FIG. 8 is a circuit diagram and an operation waveform diagram of an L load characteristic tester 60b constituting the L load property test apparatus 100b of FIG. 7, wherein (a) is a circuit diagram and (b) is an operation waveform diagram. It is principal part sectional drawing of the semiconductor element characteristic test apparatus 200 of 3rd Example of this invention. It is principal part sectional drawing of the characteristic testing apparatus 300 of the semiconductor element of 4th Example of this invention. It is a block diagram of IGBT20 of a full mold type, The figure (a) is a front view, The figure (b) is a side view. It is a figure explaining the dielectric strength test of the resin sealing part of IGBT of FIG. It is a block diagram of a semi-molded TO-3P type IGBT equipped with a cooling fin, (a) is a front view, (b) is a side view of each part before the cooling fin is inserted, (c) ) Is a back view of the IGBT itself. It is a lineblock diagram of IGBT10 which inserted clip type cooling fin 35, (a) is a front view and (b) is a side view. It is a figure explaining generating a dielectric breakdown with the bonding wire 14 and the resin sealing part 15. FIG.

  Embodiments will be described in the following examples. The figures shown below are schematic diagrams. As will be described in detail in each embodiment, test probes 58a, 58b, and 58c to be connected to the terminals (collector terminal 13a, emitter terminal 13b, and gate terminal 13c) of the IGBT 10 are used. Each of the test probes 58a, 58b, and 58c is configured as a set of a plurality (for example, three), and one of the plurality is used for detecting a current / voltage, and the rest (for example, three). Two of them (or one when the energization current is small) are for main circuit connection.

  Since illustration becomes complicated, in each example (each figure) described below, a single test probe 58a, 58b, 58c connected to the collector terminal 13a, the emitter terminal 13b, and the gate terminal 13c is shown as a representative.

In the following embodiments, the IGBT 10 will be described using the semi-mold type example described with reference to FIG. The IGBT 10 shown in FIG. 13 uses a wire 14 as a connecting conductor between the front surface electrodes (emitter electrode, gate electrode and emitter terminal 13b, gate terminal 13c) of the semiconductor chip. In the following embodiments, the present invention can be applied to any one using a wire or a connector as a connection conductor, except that a connection using a wire 14 is used. However, as shown in FIG.13 (b), since the wire 14 exists in the location close | similar to the surface of the sealing resin part 15, the problem of an insulation tolerance tends to become obvious, Therefore It is especially effective for the package using a wire. .
<Example 1>
1A and 1B are main part configuration diagrams of a semiconductor element characteristic test apparatus 100 according to a first embodiment of the present invention. FIG. 1A is a side view of the main part, and FIG. FIG. 4 is a top view of a main part viewed from an arrow A. The characteristic test apparatus 100 performs a dielectric strength test of the resin sealing portion 15 of a semiconductor element (for example, a TO-3P type IGBT 10) together with the characteristic test, and includes a voltage application jig 1. ) 600 is a characteristic test unit inside the characteristic test apparatus 100. An automatic test line will be described as an example. The resin-sealed IGBT 10 is transported on the transport rail 51 of the automatic test line, for example, from the back to the front in FIG. 1A and from the top to the bottom in FIG. 1B. The details of the transport mechanism are not shown because they are not directly related to the present invention. An insulating material 52 is disposed on the transport rail 51 at a position where the IGBT 10 is tested.

  The characteristic test unit 600 includes test probes 58a, 58b, and 58c (for example, also called contact fingers) at locations corresponding to the respective terminals (collector terminal 13a, emitter terminal 13b, and gate terminal 13c) of the IGBT 10 that is a semiconductor element. . Furthermore, a probe support portion 56 (for example, referred to as a support tube) that supports each test probe 58, a cylinder 54 of a cylinder 53 that moves the probe support portion 56 up and down, and a support column portion 55 that supports the probe support portion 56. The various characteristics of the IGBT 10 are measured and evaluated from the probe fixing portion 57 for positioning and fixing each terminal, the power source / main circuit portion 61 for outputting the applied voltage, and the values (current / voltage) detected through the probes. A characteristic evaluation unit 62 is provided. The power supply / main circuit unit 61 and the characteristic evaluation unit 62 constitute a characteristic test unit 60. The characteristic test unit 60 is connected to the terminal 13 (13a, 13b, 13c) of the IGBT 10 via the test probe 58 (58a, 58b, 58c).

  The voltage application jig 1 includes an electrode support 6, an electrode receiver 5 fixed to the electrode support 6, and an electrode 3 accommodated in the electrode receiver 5. The electrode 3 is electrically connected to the probe 58a as will be described later.

  In addition, the electrode 3 is in contact with the resin sealing portion 15 of the IGBT 10, but the electrode 3 reliably contacts the resin sealing portion 15 of the IGBT 10 and does not leave a contact mark in the resin sealing portion 15 when contacted. It is desirable that For example, it is desirable that the contact seal is not left if the resin sealing portion 15 is in surface contact. For example, the electrode 3 may be configured to elastically contact the resin sealing portion 15 of the IGBT 10. In this embodiment, the electrode 3 is elastically supported (suspended and held) on the electrode receiving portion 5 by a spring 4.

  Moreover, since the electrode 3 is for testing the dielectric strength of the resin sealing part 15 of IGBT10, it is calculated | required that it contacts the resin sealing part 15 uniformly. The electrode 3 may be made of a conductive material that is not easily worn. For example, a block-shaped conductive member (such as a copper block or a carbon block) may be supported by a plurality of springs. What is necessary is just to set it as the structure which divides | segments a block-shaped metal member into several and supports each with a spring so that it can follow by the shape (inclination with respect to a conveyance rail surface, etc.) of the resin sealing part 15 (FIG.1 (b)). reference).

  The electrode support 6 is fixed to the cylinder 54 of the cylinder 53 and moves up and down simultaneously with the test probe 58. For this reason, by forming at least one of the electrode support portion 6 and the receiving portion 5 from an insulating material, it is possible to avoid applying an unnecessary potential to the cylinder 53, the cylinder 54, and the like.

  Further, it is necessary to electrically connect the electrode 3 to the test probe 58a. The electrode 3 and the test probe 58a may be directly connected by a conductive wire. However, in order to support the electrode 3 with good conformability to the shape of the resin sealing portion 15 or to improve the maintainability of the electrode 3, Avoid connecting the lead wires directly to 3. In the present embodiment, the electrode receiving portion 5 and the spring 4 are formed of conductive members, and the electrode receiving portion 5 is connected to the test probe 58a by the wire 2 (conductive wire). The test probe 58a is connected to the collector terminal 13a during characteristic measurement. Connected (contacted).

  2A and 2B are cross-sectional views of the main part of the characteristic test apparatus 100 of the present invention. FIG. 2A is a state diagram before the test, and FIG. 2B is a state diagram during the test. In FIG. 2, a test probe 58 (for example, a contact finger) is provided with electrical wiring (conductive wire: wire) for connection to a characteristic tester 60 (excluding a sample measurement jig). Moreover, IGBT10 which has a TO-3P type resin sealing part was mentioned as an example as a semiconductor element.

  FIG. 4A shows a state before the IGBT 10 is tested, that is, a transport state and a positioning state. The test probe 58 is separated from the terminals 13a, 13b, 13c of the IGBT 10. The metal electrode 3 is also away from the resin sealing portion 15 of the IGBT 10. This is because the support portion 56 that moves the test probe 58 up and down is pushed up by the cylinder 54 of the cylinder 53. Further, the electrode support portion 6 is also pushed up, and the electrode 3 is also separated from the resin sealing portion 15 in synchronization. In this state, the transfer can be performed without damaging the IGBT 10.

  When the test probe 58 contacts the terminal 13 of the IGBT 10, the terminal block 59 supports the vicinity of the contact portion of the terminal 13 from the opposite surface (back surface) side. By supporting the terminal 13 with the terminal block 59, bending of each terminal can be prevented by the applied pressure when the test probe 58 is brought into contact with the terminal 13 on the upper surface (front surface). Further, the IGBT 10 is fixed by sandwiching the IGBT 10 between the test probe 58 and the terminal block 59.

Although the transport rail 51 is made of metal, since the insulating material 52 is placed at the measurement location, the die portion 11 on which the IGBT chip 12 is placed and the transport rail are insulated.
FIG. 2B shows a state in which the IGBT 10 is tested. When the IGBT 10 moves to the measurement position, the cylinder 54 of the cylinder 53 is lowered and the support portion 56 is lowered, and the test probes 58a, 58b and 58c supported by the support portion 56 are connected to the terminals 13a, 13b and 13c. Contact.

In addition, since the electrode support portion 6 is also lowered in synchronization therewith, the electrode 3 for testing the dielectric strength of the resin sealing portion 15 is also in contact with the resin sealing portion 15.
The electrode 3 is connected to the test probe 58a connected to the collector terminal 13a via the wire 2.

The characteristic test apparatus 100 of the present invention performs a static characteristic / dynamic characteristic test such as a leakage current characteristic test, a withstand voltage characteristic test, and an L load test apparatus shown in FIG.
The characteristic test apparatus 100 of the present invention is provided with a voltage application jig 1 (electrode 3) in the characteristic test apparatus as described above, and a test probe 58a that connects the electrode 3 to the collector terminal 13a of the IGBT 10 to which a high voltage is applied. It is configured to connect to. Therefore, the electrode 3 is brought into contact with the resin sealing portion 15 of the IGBT 10, and a high voltage is applied between the collector terminal 13 a and the emitter terminal 13 b of the IGBT 10 via the test probes 58 a and 58 b, thereby insulating the resin sealing portion 15. A tolerance test and other characteristic tests can be performed simultaneously.

Therefore, it is not necessary to provide a dedicated test apparatus that performs only the dielectric strength test, and the area occupied by a plurality of characteristic test apparatuses can be reduced.
Moreover, since the dielectric strength test of the resin sealing part 15 and other characteristic tests are simultaneously performed, the test cost can be reduced as compared with the case where the tests are performed separately.

Further, even with an IGBT in which the back surface of the die portion is exposed from the resin sealing portion such as a TO-3P type, the dielectric strength test of the resin sealing portion can be performed at low cost by using this characteristic test apparatus.
In addition, since the characteristic test is a characteristic test to be tested at the rated voltage of the IGBT 10 (or a voltage exceeding the rated voltage), if the dielectric strength is determined to be a non-defective product in this characteristic test, the customer who uses it below the rated voltage In the circuit used, insulation failure does not occur.

  By performing the dielectric strength test described above, a semiconductor element such as the IGBT 10 having the resin sealing portion 15 when the clip-type cooling fin is used is broken due to a poor insulation of the resin sealing portion 15 during actual operation. Can be prevented.

  In addition, as described above, in the normal usage method of the conventional TO-3P type IGBT 10, a high voltage was not applied to the front surface side of the resin-encapsulated portion. It wasn't. However, the appearance inspector visually inspected the resin sealing portion 15 for scratches and dents as appearance defects.

  However, by using the characteristic test apparatus 100 of the present invention, the insulation failure on the front surface side of the resin-sealed portion can be detected electrically and reliably, so that the appearance inspection is cleared as described above. An IGBT that causes insulation failure when a clip-type cooling fin is attached can be reliably eliminated.

  Further, the insulation failure discovered by the characteristic test method of the present invention is fed back to the previous process, and can be reflected in the improvement of product quality such as the review of manufacturing equipment management standards and the review of work procedures.

Also in the characteristic test apparatus 100 of the present invention, if there is a dielectric breakdown in the items of a general static characteristic test (DC test) or dynamic characteristic test, it is naturally determined as an insulation failure.
Moreover, although the semiconductor element tested with the characteristic test apparatus 100 of the present invention has been exemplified by the case where the die part 11 to which the semiconductor chip 12 is fixed is partially exposed from the resin sealing part 15 as in the TO-3P type. It can also be applied to a full mold type semiconductor element. In this case, the voltage application jig 1 needs to be a jig that applies a voltage to the resin sealing portion on the back side.

Next, a procedure for performing the leakage current characteristic test, the dielectric strength test, and the leakage current characteristic test, which are one of characteristic tests, according to the present invention will be described.
<Example 2>
3 to 5 are test process diagrams illustrating the semiconductor device characteristic test method according to the second embodiment of the present invention in the order of steps. In the figure, 61a is a power source / main circuit unit for generating a test voltage to be applied to the IGBT 10, and 62a is a characteristic evaluation unit for detecting / measuring / evaluating the leakage current of the IGBT 10.

  This semiconductor element is, for example, an IGBT having a TO-3P type resin sealing portion, and is a characteristic test method for simultaneously performing a leakage current characteristic test and a dielectric strength test as the characteristic test of FIG.

First, in FIG. 3, the IGBT 10 having the TO-3P type resin sealing portion 15 as a test sample is placed on the insulating material 52 placed on the transport rail 51.
The power source / main circuit portion 61b of the leakage current characteristic tester 60a is provided with a switch SW for short-circuiting the test probe 58c connected to the gate terminal 13c and the test probe 58b connected to the emitter terminal 13b. At this time, the switch SW is in an open state.

  Next, in FIG. 4, the switch SW is closed and the test probes 58c and 58b connected to the emitter terminal 13c and the gate terminal 13b are short-circuited. Thereafter, the test probe 58a, 58b, 58c and the electrode 3 are lowered using the column portion 55 and the electrode support portion 6 fixed to the cylinder 54 of the cylinder 53, and the respective test probes 58a, 58b, 58c are connected to the IGBT 10. The collector terminal 13a, the emitter terminal 13b, and the gate terminal 13c are brought into contact with each other, and at the same time, the electrode 3 is brought into contact with the resin sealing portion 15 of the IGBT 10.

  Next, in FIG. 5, the gate terminal 13c and the emitter terminal 13b (emitter electrode) are short-circuited because the switch SW is closed. The leakage current characteristic tester 60a applies a high voltage of the IGBT 10 between the collector terminal 13a and the emitter terminal 13b, and the characteristic evaluation unit 62a detects, measures, and evaluates the leakage current of the IGBT 10. At this time, a high voltage is simultaneously applied to the electrode 3. This high voltage is 1250 V, for example, and the rated voltage of the IGBT 10 is used. This voltage is also applied between the bonding wire 14 connected to the emitter electrode 12b and the gate pad 12c and the electrode 3. That is, the high voltage is applied to the sealing resin portion 15 via the electrode 3.

  Here, if the wire 14 is abnormally close to the surface on the front surface side of the resin sealing portion 15 or is exposed from the resin sealing portion 15, the insulation resistance against the wire 14 is insufficient or missing. Will be. Here, when the high voltage is applied via the electrode 3, a current flows between the electrode 3 and the wire 14. If the insulation resistance of the sealing resin portion is normal, this current does not flow. Therefore, if it is detected that an abnormal current flows between the electrode 3 and the wire 14, the resin sealing covering the bonding wire 14 is performed. The insulation failure of the part 15 can be detected. That is, the leakage current test and the dielectric strength test can be performed simultaneously.

  FIG. 6 is an applied voltage waveform diagram when a leakage current characteristic test is performed using the leakage current characteristic test apparatus 100a of the present invention. Using a leakage current characteristic tester constituting the leakage current characteristic test apparatus 100a, the voltage applied between the collector terminal 13a and the emitter terminal 13b of the IGBT 10 is increased stepwise, for example, to a predetermined voltage (rated voltage: here Then, the voltage is lowered at the stage (point B) that reaches 1250V). This voltage is also applied to the resin sealing portion 15. If there is a poor insulation portion in the resin sealing portion 15, the leakage current abnormally rises below a predetermined voltage (1200V). The abnormal increase of the leakage current is detected, the applied voltage is lowered (C point), and it is determined that the insulation failure of the resin sealing portion 15 of the IGBT 10 is present. When there is no insulation failure location in the resin sealing portion 15, when an abnormal increase in leakage current or a value exceeding the standard value is detected, it is determined as a leakage current failure. In addition, the applied voltage is not increased stepwise but may be increased all at once to the ultimate voltage.

  FIG. 7 is a configuration diagram of a main part of an L load characteristic test apparatus 100b which is one of the characteristic test apparatuses 100 of the present invention. In the figure, reference numeral 61b denotes a power source / main circuit section for supplying a main current to the IGBT 10. Reference numeral 62b in the figure denotes a characteristic evaluation unit that detects, measures, and evaluates the collector voltage and collector current of the IGBT 10.

  FIG. 8 is a main circuit diagram and an operation waveform diagram of the L load characteristic tester 60b constituting the L load characteristic test apparatus 100b of FIG. 7, wherein FIG. 8 (a) is a main circuit diagram, and FIG. It is a waveform diagram. In FIG. 7, the circuit of the characteristic evaluation unit 62b is not shown.

  The power source / main circuit unit 61b of the L load characteristic tester 60b is composed of an inductance L as a load and a power source E (E is also used as a power source voltage). In this example, a circuit incorporating a MOSFET 10 'as an element to be tested is used. In the test method, a predetermined gate voltage is applied to the gate of the MOSFET 10 ′ to turn on the MOSFET 10 ′, and a collector current Ic flows from the power source E through the inductance L to the IGBT 10. With this current, energy is accumulated in the inductance L. Next, the MOSFET 10 'is turned off to cut off the drain current Id. The energy accumulated in the inductance L is consumed by the MOSFET 10.

  At this time, the drain voltage Vd of the MOSFET 10 'jumps up to the avalanche voltage (see FIG. 5B). The avalanche voltage is maintained until there is no energy stored in the inductance L. After the energy is consumed, the drain voltage Vd becomes the power supply voltage E. If this avalanche voltage cannot be maintained, the MOSFET 10 'is determined to be defective.

When performing the L load characteristic test as described above, the power supply voltage E or the avalanche voltage is also applied to the electrode 3.
Here, if the wire 14 is abnormally close to the surface on the front surface side of the resin sealing portion 15 or is exposed from the resin sealing portion 15, the insulation resistance against the wire 14 is insufficient or missing. Will be. Here, when the power supply voltage E or the avalanche voltage is applied via the electrode 3, a current flows between the electrode 3 and the wire 14. If the insulation resistance of the sealing resin portion is normal, this current does not flow. Therefore, if it is detected that an abnormal current flows between the electrode 3 and the wire 14, the resin sealing covering the bonding wire 14 is performed. The insulation failure of the part 15 can be detected. That is, the L load characteristic test and the dielectric strength test can be performed simultaneously.

  Thus, when the MOSFET is turned off by the energy stored in the inductance load, the drain voltage Vd jumps to the avalanche voltage. Since this avalanche voltage is applied to the resin sealing portion 15, the dielectric strength test of the resin sealing portion 15 can be performed at the same time.

  When the IGBT 10 is used as an element to be tested, it is necessary to connect a diode D in parallel with the inductance L in FIG. The diode D is for circulating the energy accumulated in the inductance L when the IGBT 10 is turned off, and is connected with the cathode on the power source E side and the anode on the IGBT 10 side. When the IGBT 10 is turned off, the energy accumulated in the inductance L flows back through the diode D and is consumed by the forward drop of the diode D.

At this time, the power supply voltage E is applied to the collector of the IGBT 10, and the power supply voltage E is also applied to the electrode 3. If the wire 14 is abnormally close to the surface on the front surface side of the resin sealing portion 15 or is exposed from the resin sealing portion 15, the insulation resistance to the wire 14 is insufficient or missing. It will be. Here, when the power supply voltage E is applied via the electrode 3, a current flows between the electrode 3 and the wire 14. If the insulation resistance of the sealing resin portion is normal, this current does not flow. Therefore, if it is detected that an abnormal current flows between the electrode 3 and the wire 14, the resin sealing covering the bonding wire 14 is performed. The insulation failure of the part 15 can be detected. That is, the L load characteristic test and the dielectric strength test can be performed simultaneously.
<Example 3>
FIG. 9 is a cross-sectional view of an essential part of a semiconductor element characteristic test apparatus 200 according to the third embodiment of the present invention. 9 is different from the characteristic test apparatus 100 in FIG. 1 in that the voltage application jig 1 and the collector electrode 13a are connected to each other, and a part of the electrode 3 constituting the voltage application jig 1 is connected to the IGBT. The point is that the G portion is brought into contact with the die portion 11 on which the chip 12 is mounted and exposed from the resin sealing portion 15. With this configuration, the wire 2 connecting the collector terminal 13a and the voltage application jig 1 is not necessary. In this case, the same effect as described above can be obtained.
<Example 4>
FIG. 10 is a cross-sectional view of an essential part of a semiconductor element characteristic test apparatus 300 according to the fourth embodiment of the present invention. The characteristic test apparatus 300 in FIG. 10 is different from the characteristic test apparatus 200 in FIG. 9 in that the voltage application jig 1 is a clip-type voltage application jig 1a and the resin sealing portion 15 on the upper surface of the IGBT 10 and the die portion 11 on the lower surface. This is the point where the back side of is inserted. With this configuration, the insulating electrode support portion 6 and the metal receiving portion 5 required in the characteristic test apparatus 100 of FIG. 1 are not required, and the metal electrode 3 is simply replaced with the clip-type voltage application jig 1a. However, a device that sandwiches the IGBT 10 in the clip-type voltage application jig 1a and a device that removes the IGBT 10 are newly required. If these devices are not available, the clip-type voltage application jig 1a may be attached and detached manually. In the case of this embodiment, the same effect as that of the above embodiment can be obtained.

  In the first to fourth embodiments, the IGBT 10 having the TO-3P type resin sealing portion 15 is taken as an example of the semiconductor element. However, the IGBT having the TO-220P type resin sealing portion or the IGBT is used. The present invention can be applied to other MOSFETs and diodes.

1, 1b, 72 Voltage application jig 2 Wire 3 Electrode 4 Spring 5 Electrode receiving part 6 Electrode support part 10 IGBT (TO-3P type)
11 Die part 11a Back surface 12 IGBT chip 13a Collector terminal 13b Emitter terminal 13c Gate terminal 14 Bonding wire 15 Resin sealing part 15a Surface 20 IGBT (TO-3PF)
51 Conveying rail 52 Insulating plate 53 Cylinder 54 Cylinder 55 Supporting part 56 Probe support part 57 Probe fixing part 58 Test probe (generic name)
58a Test probe (connected to collector terminal)
58b Test probe (connected to emitter terminal)
58c Test probe (connected to gate terminal)
59 Terminal Block 60 Characteristic Tester 60a Leakage Current Characteristic Tester 60b L Load Characteristic Tester 61 Power Supply / Main Circuit Unit 62 Characteristic Evaluation Unit 71 AC Voltage Application Unit 100, 200, 300 Semiconductor Device Characteristic Test Device 100a Leakage current characteristic test apparatus 100b of the present invention L load characteristic test apparatus 500 of the present invention 500 Dedicated dielectric strength test apparatus 600 Semiconductor element characteristic test section

Claims (7)

A semiconductor chip, a conductor to which a high potential electrode on the back surface of the semiconductor chip is connected, a high potential terminal to be connected to the conductor, a low potential terminal to be connected to a low potential side electrode of the semiconductor chip by a connection conductor, A semiconductor device characteristic test apparatus comprising: a control terminal connected to a control electrode of the semiconductor chip by a connection conductor; and a front surface of the conductor, and a resin sealing portion covering the semiconductor chip and the connection conductor. There,
A test probe that contacts each of the high potential terminal, the low potential terminal, and the control terminal, and a predetermined voltage applied to each of the high potential terminal, the low potential terminal, and the control terminal via the test probe. Voltage detecting means for applying voltage, detecting means for detecting at least one of voltage and current of each of the high potential terminal, the low potential terminal, and the control terminal via the test probe, and the semiconductor from the detection result Evaluation means for evaluating the characteristics of the element, a test electrode in contact with the front surface of the resin sealing portion, and a connection means for connecting the test electrode to a high potential terminal of the semiconductor element,
The test probe is brought into contact with the high-potential terminal, the low-potential terminal, and the control terminal, the test electrode is brought into contact with the resin sealing portion , and a predetermined voltage is applied from the voltage application unit,
The evaluation means evaluates at least one of static characteristics or dynamic characteristics of the semiconductor element based on the detected value and evaluates the dielectric strength of the resin sealing portion . The connecting means includes
2. The semiconductor element characteristic test apparatus according to claim 1, wherein the test element is a lead wire connecting between the test electrode and a test probe in contact with the high potential terminal. 2. The characteristic testing apparatus for a semiconductor element according to claim 1, wherein the connecting means is configured to bring the test electrode into direct contact with the conductor. The said test electrode is supported by the elastic body, The characteristic test apparatus of the semiconductor element as described in any one of Claims 1-3 characterized by the above-mentioned. A conductive clip electrode that elastically sandwiches the semiconductor element from the front surface side of the resin sealing portion and the back surface side of the conductor is attached to the semiconductor element,
2. The semiconductor device characteristic testing apparatus according to claim 1, wherein the clip electrode is replaced with the test electrode and the connection means.   2. The characteristic test apparatus for a semiconductor device according to claim 1, wherein the static characteristic test is at least one of a leakage current characteristic test and a withstand voltage characteristic test, and the dynamic characteristic test is an L load withstand test. In the semiconductor element characteristic test method performed using the semiconductor element characteristic test apparatus according to any one of claims 1 to 6,
Apply a voltage equal to or higher than the rated voltage of the semiconductor element between at least the high-potential electrode and the low-potential side electrode, and perform a dielectric strength test of the resin sealing portion simultaneously with at least one of the static characteristic test or the dynamic characteristic test of the semiconductor element. A method for testing characteristics of a semiconductor device, characterized in that: