Semiconductor test apparatus and method for evaluating performance of semiconductor test apparatus

Abstract

A semiconductor testing device (1) is configured so that it is possible to test electrical properties of a semiconductor element (70), the semiconductor testing device (1) conducting a performance evaluation by using a test element (60) which simulates the semiconductor element (70). The semiconductor testing device (1) comprises: a stage (10) for fixing a semiconductor element; a stage electrode (12) that is provided to the stage (10) and connects to a positive electrode (62); a voltage sensor (30) that detects a voltage between the positive electrode (62) and a negative electrode (65); a power source (40) that supplies a current between the positive electrode (62) and the negative electrode (65); and a current sensor (50) that detects a current between the positive electrode (62) and a negative electrode sense electrode (66).

Description

Technical Field

[0001] The present disclosure relates to a semiconductor test apparatus and a method for evaluating the performance of a semiconductor test apparatus.

Background Art

[0002] Conventionally, various proposals have been made for semiconductor test apparatuses for testing semiconductor elements, such as Japanese Patent Application Laid-Open No. 2006-337247.

[0003] A semiconductor element includes, for example, a substrate, a collector electrode formed on the lower surface of the substrate, and an emitter electrode and a control electrode formed on the upper surface of the substrate.

[0004] Generally, a semiconductor test apparatus includes a stage on which a semiconductor element is disposed and a plurality of probes disposed on the upper surface of the stage.

[0005] The stage is provided with an electrode that contacts the collector electrode of the semiconductor element. The plurality of probes disposed above the stage include a first probe that contacts the emitter electrode of the semiconductor element and a second probe that contacts the control electrode.

[0006] When testing the characteristics of a semiconductor element, the semiconductor element is placed on the stage and the first electrode is brought into contact with the collector electrode. The first probe is brought into contact with the emitter electrode and the second probe is brought into contact with the control electrode.

[0007] Then, a voltage is applied to the control electrode, and then a current is passed between the collector electrode and the emitter electrode to test the semiconductor element.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] In the semiconductor test apparatus as described above, it is impossible to detect disadvantages such as deterioration of the electrodes of the semiconductor test apparatus and each probe, and it is impossible to determine the performance of the semiconductor test apparatus. As a result, there may arise a problem that the test of the semiconductor element cannot be accurately performed.

[0010] The present disclosure has been made in view of the above problems, and an object thereof is to provide a semiconductor test apparatus capable of evaluating the performance of a semiconductor test apparatus and a method for evaluating the performance of a semiconductor test apparatus in a semiconductor test apparatus for testing a semiconductor element.

Means for Solving the Problems

[0011] The semiconductor test apparatus of the present disclosure is a semiconductor test apparatus that is formed to be capable of testing the electrical characteristics of a semiconductor element and is capable of performing performance evaluation using a test element that mimics the semiconductor element. The test element includes a substrate having a first main surface and a second main surface, a positive electrode formed on the first main surface, a negative electrode formed on the second main surface, a negative sense electrode, and a control electrode that controls the electrical conduction between the positive electrode and the negative electrode in response to a control signal. The semiconductor test apparatus includes a stage for fixing the semiconductor element, a stage electrode provided on the stage and connected to the positive electrode, a voltage sensor for detecting the voltage between the positive electrode and the negative electrode, a power supply for supplying a current between the positive electrode and the negative electrode, and a current sensor for detecting the current between the positive electrode and the negative sense electrode. This semiconductor test apparatus can perform a performance evaluation as to whether the semiconductor test apparatus is sound based on the measured value of the current sensor.

[0012] The performance evaluation method of the semiconductor test device of the present disclosure is a method for evaluating the performance of a semiconductor test device capable of testing the electrical characteristics of a semiconductor element and using a test element imitating the semiconductor element. The test element includes a substrate having a first main surface and a second main surface, a positive electrode formed on the first main surface, a negative electrode formed on the second main surface, a negative electrode sense electrode, and a control electrode that controls the electrical conduction between the positive electrode and the negative electrode according to a control signal. The semiconductor test device includes a stage on which the first main surface is disposed and which is connected to the positive electrode, a voltage sensor that detects the voltage between the positive electrode and the negative electrode, a power supply that supplies a current between the positive electrode and the negative electrode, and a current sensor that detects the current between the positive electrode and the negative electrode sense electrode. The performance evaluation method of the semiconductor test device includes a step of applying a voltage to the control electrode, a step of supplying a current between the positive electrode and the negative electrode, and a step of acquiring, by the current sensor, the current between the positive electrode and the negative electrode sense electrode while the voltage sensor detects the potential difference between the negative electrode and the positive electrode. According to this performance evaluation method of the semiconductor test device, it is possible to evaluate whether the semiconductor test device is sound based on the measured value of the current sensor.

Effects of the Invention

[0013] According to the semiconductor test device and the performance evaluation method of the semiconductor test device of the present disclosure, in a semiconductor test device for testing a semiconductor element, the performance of the semiconductor test device can be evaluated.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0015] Embodiment 1. FIG. 1 is a cross-sectional view showing the semiconductor test device 1 according to Embodiment 1 of the present invention. The semiconductor test device 1 performs performance evaluation of the semiconductor test device 1 using the test element 60.

[0016] The test element 60 is an element created by simulating semiconductor elements such as IGBT (Insulated Gate Bipolor Transistor) and MOSFEAT (metal-oxide-semiconductor field-effect transistor).

[0017] The test element 60 includes a substrate 61, a collector electrode (positive electrode) 62, a voltage sense electrode 63, a control electrode 64, an emitter electrode (negative electrode) 65, a voltage sense electrode 66, and a current sense electrode 67.

[0018] The substrate 61 includes a main surface 68 and a main surface 69, and the main surface 68 and the main surface 69 are arranged in the thickness direction of the substrate 61.

[0019] The collector electrode 62 and the voltage sense electrode 63 are formed on the main surface 68. The control electrode 64, the emitter electrode 65, the voltage sense electrode 66, and the current sense electrode 67 are formed on the main surface 69.

[0020] In the example shown in FIG. 1, the test element 60 is an element simulating an IGBT. Therefore, the collector electrode 62 is formed in a planar shape.

[0021] The semiconductor test device 1 includes a control device 2, a drive circuit 3, a stage 10, a probe assembly 20, a voltage sensor 30, a constant current source 40, a current sensor 50, and a resistor 55.

[0022] The stage 10 includes a stage body 11, electrodes 12, sense electrodes 13, and a fixing device 14.

[0023] The stage body 11 includes a flat mounting surface 15. The electrodes 12 and the sense electrodes 13 are provided on the mounting surface 15.

[0024] The fixing device 14 is a device that adsorbs a test element or a semiconductor element disposed on the upper surface of the mounting surface 15 and fixes the test element or the semiconductor element to the upper surface of the mounting surface 15. The fixing device 14 includes a suction tube 16 formed in the stage body 11 and an intake device connected to the suction tube 16. A suction port 17 of the suction tube 16 is formed in the mounting surface 15, and the intake device is not shown.

[0025] The electrodes 12 include a plurality of probes. The probe assembly 20 is disposed above the stage 10, and the probe assembly 20 is formed to be movable in the vertical direction.

[0026] The probe assembly 20 includes a control probe 24, an emitter probe 25, a voltage sense probe 26, and a current sense probe 27. In the example shown in FIG. 1, a plurality of emitter probes 25 are provided.

[0027] The voltage sensor 30 is connected to the sense electrode 13 and the voltage sense probe 26. Specifically, the positive terminal of the voltage sensor 30 is connected to the sense electrode 13, and the negative terminal of the voltage sensor 30 is connected to the voltage sense probe 26.

[0028] The constant current source 40 is connected to the electrode 12 through the positive electrode line 56, and the constant current source 40 is connected to the resistor 55 through the negative electrode line 57. The resistor 55 is connected to the constant current source 40 and the current sensor 50. The current sensor 50 is connected to the resistor 55 and the current sense probe 27. The resistor 55 is, for example, 200 Ω.

[0029] At the node 59 between the constant current source 40 and the resistor 55, the negative electrode line 58 is connected, and the negative electrode line 58 is connected to each of the plurality of emitter probes 25. The drive circuit 3 is connected to the control probe 24.

[0030] The control device 2 controls the driving of the drive circuit 3, the stage 10, the probe assembly 20, and the constant current source 40, and the control device 2 acquires the output values from the voltage sensor 30 and the constant current source 40.

[0031] Here, a case where the semiconductor test apparatus 1 is driven using a normal test element 60 will be described.

[0032] The control device 2 drives the fixing device 14 of the stage 10 to fix the test element 60 disposed at a predetermined position.

[0033] When the test element 60 is sucked and fixed, the electrode 12 is connected to the collector electrode 62, and the sense electrode 13 is connected to the voltage sense electrode 63.

[0034] Since the electrode 12 includes a plurality of probes, variations in the contact resistance between the electrode 12 and the collector electrode 62 are suppressed.

[0035] For example, when the electrode 12 is formed in a planar shape, the planar electrode 12 and the planar collector electrode 62 come into contact with each other. In this case, due to warping of the substrate 61 or entry of foreign matter between the electrode 12 and the collector electrode 62, the contact resistance between the electrode 12 and the collector electrode 62 is likely to vary. On the other hand, by forming the electrode 12 with a plurality of probes, it is possible to suppress the occurrence of variations in the contact resistance as described above.

[0036] The control device 2 lowers the probe assembly 20. As a result, the control probe 24 and the control electrode 64 come into contact, and the emitter electrode 65 and the emitter probe 25 come into contact. Similarly, the voltage sense electrode 66 and the voltage sense probe 26 come into contact, and the current sense probe 27 and the current sense electrode 67 come into contact.

[0037] The control device 2 drives the drive circuit 3 to apply a predetermined voltage to the control electrode 64 through the control probe 24, and the control device 2 drives the constant current source 40.

[0038] As a result, electrical conduction paths are formed between the collector electrode 62 and the emitter electrode 65, between the collector electrode 62 and the voltage sense electrode 66, and between the collector electrode 62 and the current sense electrode 67.

[0039] Similarly, electrical conduction paths are formed between the voltage sense electrode 63 and the emitter electrode 65, between the voltage sense electrode 63 and the voltage sense electrode 66, and between the voltage sense electrode 63 and the current sense electrode 67.

[0040] The voltage sensor 30 detects the voltage between the sense electrode 13 and the voltage sense probe 26. The internal resistance within the voltage sensor 30 is several megaohms and hardly flows through the voltage sense probe 26, and the measurement error is suppressed to be small. As a result, the voltage sensor 30 can accurately measure the potential difference between the voltage sense electrode 63 and the voltage sense electrode 66.

[0041] Assuming that the saturation voltage between the collector electrode 62 and the emitter electrode 65 is Vce(sat), the potential difference between the voltage sense electrode 63 and the voltage sense electrode 66 is the saturation voltage (Vcs(sat)), and the voltage sensor 30 can accurately measure the saturation voltage Vce(sat).

[0042] In the above example, the voltage sense electrode 66 is formed separately from the emitter electrode 65, but the emitter electrode 65 and the voltage sense electrode 66 may be integrally formed.

[0043] The current from the constant current source 40 flows through the current path R1 that sequentially passes through the electrode 12, the collector electrode 62, the emitter electrode 65, and the emitter probe 25, and the current path R2 that sequentially passes through the electrode 12, the collector electrode 62, the current sense electrode 67, the current sense probe 27, the current sensor 50, and the resistor 55.

[0044] The resistor 55 is, for example, 200 Ω. As a result, the amount of current flowing through the current path R2 is about 1 / 10000 of the amount of current flowing through the current path R1.

[0045] Assuming that the saturation voltage between the collector electrode 62 and the current sense electrode 67 is Vcs(sat), the measured value of the current sensor 50 is the current amount Is, and the resistance value of the resistor 55 is R3, the following formula (1) holds. Vce(sat)=Vcs(sat)+Is×R3···(1) For example, assuming that the saturation voltage Vce(sat) when a current of 200 (A) is passed is 1.5 (V), and Vcs(sat) when several (mA) is passed through the current sense electrode 67 is 1 (V). When the resistor 3 is 200 Ω, the above formula (1) becomes the following formula (2). 1.5(V)=1(V)+Is×200(Ω)···(2) As a result, Is = 2.5 (mA).

[0046] Thus, in the test element 60, by providing the current sense electrode 67 separately from the emitter electrode 65 and providing the resistor 55 in the current path R2 passing through the current sense electrode 67, the amount of current (Is) passing through the current path R2 can be set to be about 1 / 10000 of the amount of current passing through the current path R1.

[0047] FIG. 2 is a flowchart for determining the performance test of the semiconductor test apparatus 1. The preparation step (S10) includes a step of arranging the test element 60 at a predetermined position on the mounting surface 15 and a step of the control device 2 driving the fixing device 14.

[0048] In this preparation step, the emitter electrode 65 of the test element 60 is in good contact with the electrode 12 of the semiconductor test apparatus 1, and the emitter electrode 65 is in good contact with the sense electrode 13.

[0049] The probe contact step (S20) is a step in which the probe assembly 20 descends and each probe of the semiconductor test apparatus 1 contacts each electrode of the test element 60.

[0050] Specifically, the control probe 24 contacts the control electrode 64, and the emitter electrode 65 contacts the emitter probe 25. Similarly, the voltage sense electrode 66 contacts the voltage sense probe 26, and the current sense probe 27 contacts the current sense electrode 67.

[0051] The energization step (S30) includes a step of applying a predetermined voltage to the control electrode 64 and a step of driving the constant current source 40 to energize a constant current through the current paths R1 and R2. Note that the constant current source 40 supplies a constant current of 200 (A).

[0052] The current detection step (S40) is a step in which the current sensor 50 measures the amount of current. Note that the current sensor 50 transmits the measured amount of current to the control device 2.

[0053] The determination step (S50) determines whether the amount of current measured by the current sensor 50 satisfies a predetermined requirement (standard). Here, the predetermined requirement can be a requirement that takes into account the appropriate value as the amount of current (Is) in advance and measurement variations. For example, using a plurality of test elements 60, measuring a plurality of times, and calculating the amount of deviation from the appropriate value based on the measurement results. Then, as the predetermined requirement, for example, it can be adopted that the amount of current (Is) is within a predetermined range based on the appropriate value, or the amount of deviation from the reference value is within a predetermined range.

[0054] Here, a method for calculating the appropriate value of the amount of current (Is) will be described. First, let the contact resistance between the emitter electrode 65 and the emitter probe 25 in the current path R1 be the contact resistance R11, and the contact resistance between the current sense electrode 67 and the current sense probe 27 in the current path R2 be the contact resistance R12. Let the resistance value of the resistor 55 be the resistance value R3. Since the potential differences of the current path R1 and the current path R2 are equal, the following formula (3) holds. (200(A) - Is)×R11 = Is×(R3 + R12) ··· (3) The contact resistance R11 can be calculated based on the materials of the emitter electrode 65 and the emitter probe 25, the probe diameter at the tip of the emitter probe 25, the shape of the emitter probe 25, the pressing pressure at the tip of the emitter probe 25, and the like.

[0055] The following formula 1 is a formula for calculating the contact resistance R11.

[0056]

Formula

[0057] Note that ρ(25) represents the resistance of the emitter probe 25. E(25) represents the elastic modulus of the emitter probe 25. P(25) represents the pressing pressure at the tip of the emitter probe 25. R(25) represents the radius of curvature at the tip of the emitter probe 25.

[0058] Similarly, the contact resistance R12 can be calculated based on the materials of the current sense electrode 67 and the current sense probe 27, the probe diameter of the current sense probe 27, the pressing pressure, and so on. The following formula (2) is the formula for calculating the contact resistance R12.

[0059] [Formula]

[0060] Here, ρ(27) represents the resistance of the current sense probe 27. E(27) represents the elastic modulus of the current sense probe 27. P(27) represents the pressing pressure at the tip of the current sense probe 27. R(27) represents the radius of curvature at the tip of the current sense probe 27.

[0061] In formulas (1) and (2), the respective resistances and elastic moduli of the emitter probe 25 and the current sense probe 27 can be obtained by measuring them in advance. And the pressing pressures of the emitter probe 25 and the current sense probe 27 can be set in advance.

[0062] Therefore, before performing the performance evaluation of the semiconductor test apparatus 1, the contact resistance R11 and the contact resistance R12 can be calculated.

[0063] Then, an appropriate value of the current amount (Is) can be calculated from the above formula (3) and the contact resistances R11 and R12.

[0064] The control device 2 stores an appropriate value of the current amount (Is) and information regarding the above-mentioned predetermined requirements.

[0065] In the determination step (S50), the control device 2 determines whether the current amount acquired from the current sensor 50 in the current detection step (S40) satisfies the predetermined requirements.

[0066] Here, when the amount of current measured by the current sensor 50 does not meet the predetermined requirements, for example, when the fixed position of the test element 60 is displaced, or when the tip portions of the emitter probe 25 and the current sense probe 27 are worn, or when the pressing pressure of the emitter probe 25 and the current sense probe 27 is not appropriate, etc. can be considered.

[0067] Therefore, when the control device 2 determines in the determination step (S50) that the amount of current measured by the current sensor 50 does not meet the predetermined requirements (No in S50), the control device 2 determines that the semiconductor test device 1 is defective and performs an adjustment process (S60).

[0068] Examples of the adjustment process include notifying the operator that the semiconductor test device 1 is defective and adjusting the pressing pressure of the emitter probe 25 and the current sense probe 27.

[0069] On the other hand, when the control device 2 determines that the amount of current measured by the current sensor 50 meets the predetermined requirements (Yes in S50), the control device 2 determines that the semiconductor test device 1 is sound.

[0070] Then, the control device 2 proceeds to a test step (S70) for performing a characteristic test of the semiconductor element 70.

[0071] FIG. 3 is a diagram schematically showing a test step for performing a characteristic test of the semiconductor element 70. The test element 60 is created by imitating the semiconductor element 70, and the semiconductor element 70 is configured in the same manner as the test element 60.

[0072] The semiconductor element 70 includes a substrate 71, a collector electrode 72, a voltage sense electrode 73, a control electrode 74, an emitter electrode 75, a voltage sense electrode 76, and a current sense electrode 77.

[0073] The substrate 71 includes a main surface 78 and a main surface 79, and the main surface 78 and the main surface 79 are arranged in the thickness direction of the substrate 71.

[0074] The collector electrode 72 and the voltage sense electrode 73 are formed on the main surface 78. The control electrode 74, the emitter electrode 75, the voltage sense electrode 76, and the current sense electrode 77 are formed on the main surface 79.

[0075] Then, the semiconductor test apparatus 1 adsorbs and fixes the semiconductor element 70 to the mounting surface 15 of the stage 10. Then, in the semiconductor test apparatus 1, the control probe 24 and the control electrode 74 are brought into contact, and the emitter electrode 75 and the emitter probe 25 are brought into contact. Similarly, the voltage sense electrode 76 and the voltage sense probe 26 are brought into contact, and the current sense probe 27 and the current sense electrode 77 are brought into contact. Then, a predetermined voltage is applied to the control electrode 74 or the like to perform a characteristic test of the semiconductor element 70.

[0076] As described above, according to the semiconductor test apparatus 1 according to the first embodiment, after confirming the soundness of the semiconductor test apparatus 1, a characteristic test of the semiconductor element 70 can be performed.

[0077] Embodiment 2. FIG. 4 is a cross-sectional view showing the semiconductor test apparatus 1 and the test element 60A.

[0078] In addition to the configuration of the test element 60, the test element 60A includes resistors 80 and 81. The resistor 80 is formed between the collector electrode 62, the emitter electrode 65, and the voltage sense electrode 66. The resistor 81 is formed between the collector electrode 62 and the current sense electrode 67.

[0079] FIG. 5 is a plan view of the test element 60A when viewed from the main surface 68 (solder surface) side, and FIG. 6 is a plan view of the test element 60A when viewed from the main surface (component surface) 69 side.

[0080] On the main surface 68, a collector electrode 62, a voltage sense electrode 63, and a conductor pattern 91A are formed.

[0081] On the main surface 69, an emitter electrode 65, a conductor pattern 91B, a current sense electrode 67, and resistors 80 and 81 are formed.

[0082] In the examples shown in FIGS. 5 and 6, the voltage sense electrode 63 is integrated with the collector electrode 62, and the control electrode 64 is not shown. Through holes 95A and 95B penetrating from the main surface 68 to the main surface 69 are formed in the substrate 61. A conductive member 96A is formed in the through hole 95A, and a conductive member 96B is formed in the through hole 95B. The conductive members 96A and 96B are formed by plating drill holes. Note that a plurality of through holes 95A and 95B are formed, and a plurality of conductive members 96A and 96B are also formed.

[0083] On the main surface 68, the collector electrode 62 is connected to the conductive member 96A. On the main surface 69, the resistor 80 is connected to the conductive member 96A, and the conductor pattern 91B is connected to the resistor 80. The emitter electrode 65 is connected to the conductor pattern 91B. Therefore, the collector electrode 62 is connected to the emitter electrode 65 through the conductive member 96A, the resistor 80, and the conductor pattern 91B.

[0084] On the main surface 68, the conductor pattern 91A connects the collector electrode 62 and the conductive member 96B. On the main surface 69, the conductive member 96B is connected to the resistor 81, and the resistor 81 is connected to the current sense electrode 67.

[0085] Therefore, the collector electrode 62 is connected to the current sense electrode 67 through the conductor pattern 91A, the conductive member 96B, and the resistor 81. Note that the conductor patterns 91A and 91B are wiring patterns formed of copper or the like.

[0086] In FIG. 4, the resistor 80 simulates the saturation voltage Vce(sat) between the collector electrode 62 and the emitter electrode 65. The resistor 81 simulates the saturation voltage Vcs(sat) between the collector electrode 62 and the current sense electrode 67.

[0087] For example, when a current of 200 (A) is passed through a semiconductor element using the semiconductor test device 1 and Vce(sat) is 1.5 (V), the resistor 80 is preferably 7.5 (mΩ). Also, when Vcs(sat) of the semiconductor element is 1 (V) and the amount of current flowing through the current sense electrode 67 is 2 (mA), the resistor 81 is preferably 500 (Ω).

[0088] Since the current path R1 through the current sense probe 27 assumes the sense current, by setting the resistors 80 and 81 as described above, the current capacity of the current path R1 can be made smaller than that of the current path R2 through the emitter probe 25. For example, when the resistor 55 is 200 (Ω) and the rated current of the semiconductor test device 1 is 500 (A), the power of the resistor 55 is 100 (kW). Since the semiconductor test device 1 is not a device that constantly passes current, it is not always necessary to have a 100 (kW) resistor, but a high-power resistor is required. However, if the current path through the current sense probe 27 is only the sense current, there is no need to prepare a high-power resistor, which is advantageous in terms of cost and design.

[0089] Furthermore, the measured value of the sense current in the test element 60A can be made close to the sense current of the semiconductor element 70. This has the advantage that it is easy to set the predetermined requirements (specifications) in the above-described determination step (S50) and it is easy to detect a deviation from the predetermined requirements (specifications).

[0090] Furthermore, in the above formula (3), the amount of current (Is) flowing through the current sense probe 27 is determined by the ratio of the sum of the contact resistance R11 and the resistance value R3 to the contact resistance R12. Therefore, when the contact resistance R12 increases, a larger current than the assumed amount of current (Is) may flow through the current path of the current sense probe 27.

[0091] On the other hand, by providing the resistor 81 as in the test element 60A, it is possible to suppress an excessive amount of current flowing through the current sense probe 27.

[0092] Note that the flow for determining the performance test of the semiconductor test apparatus 1 using the test element 60A is the same as that in the first embodiment described above.

[0093] Embodiment 3. FIG. 7 is a cross-sectional view showing the semiconductor test apparatus 1 and the test element 60B.

[0094] The test element 60B includes diodes 85 and 86 in addition to the configuration of the test element 60.

[0095] The diode 85 is connected between the collector electrode 62 and the emitter electrode 65, and the diode 86 is connected between the collector electrode 62 and the current sense electrode 67.

[0096] The diode 85 simulates the saturation voltage Vce(sat) between the collector electrode 62 and the emitter electrode 65.

[0097] The diode 86 simulates the saturation voltage Vcs(sat) between the collector electrode 62 and the current sense electrode 67.

[0098] For example, when a current of 200 (A) is passed through the semiconductor element to be tested using the semiconductor test apparatus 1 and Vce(sat) is 1.5 (V), the forward voltage (Vf) of the diode 85 is preferably 1.5 (V). Also, when Vcs(sat) of the semiconductor element is 1 (V) and the amount of current (Is) flowing through the current sense probe 27 is 2 (mA), the forward voltage (Vf) of the diode 86 is preferably 1.5 (V). Thereby, since the current path flowing through the current sense probe 27 assumes the sense current, it can be designed with a smaller current capacity compared to the current path flowing through the emitter probe 25.

[0099] By manufacturing a substrate 41 that simulates the ratio of the collector current to the sense current for each type of semiconductor element 70 to be tested, the soundness of the semiconductor test apparatus 1 can be confirmed in more detail.

[0100] By using a Schottky barrier diode or the like in which the forward voltage Vf of the diodes 85 and 86 is low and there are many types of forward voltage Vf, the ratio between the collector current and the sense current of the semiconductor element 70 can be simulated more accurately.

[0101] As a result, when the current changes, the fluctuation of the forward voltage Vf is smaller than the voltage fluctuation of the resistor, making it easier to confirm the soundness of the semiconductor test apparatus 1.

[0102] Note that the flow for determining the performance test of the semiconductor test apparatus 1 using the test element 60B is the same as that in the first embodiment described above. Embodiment 4. FIG. 8 is a cross-sectional view showing the semiconductor test apparatus 1 and the test element 60C according to Embodiment 4. The configuration of the test element 60C is similar to that of the test element 60 in the first embodiment. The test element 60C includes a main surface 68C, a collector electrode 62C, and a voltage sense electrode 63C, and the configuration other than this is substantially the same as that of the test element 60.

[0103] The main surface 68C is formed in an uneven shape. The collector electrode 62C and the voltage sense electrode 63C are formed on the main surface 68C. The collector electrode 62C and the voltage sense electrode 63C include an underlayer such as nickel and a gold plating layer formed on the surface of the underlayer. The film thickness of the gold plating layer is, for example, several μm. The collector electrode 62C and the voltage sense electrode 63C are also formed in an uneven shape similar to the main surface 68C. The main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C are processed, for example, in a crown shape.

[0104] Generally, semiconductor testing is carried out in a clean room. Therefore, the size of foreign matter getting onto the stage 10 is about several hundred micrometers. When foreign matter as described above is sandwiched between the main surface 68C and the mounting surface 15, the surface roughness of the main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C is set so as to enter into the recesses of the main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C. The arithmetic mean roughness Ra of the main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C is, for example, 500 μm or more and 1000 μm or less.

[0105] When forming the uneven shape on the main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C, first, the underlayer of the collector electrode 62C and the underlayer of the voltage sense electrode 63C are formed on the main surface where the uneven shape is not formed.

[0106] After forming the underlayers of the collector electrode 62C and the voltage sense electrode 63C, for example, sandblasting is performed on the main surface and each underlayer. As a result, the main surface 68C with the uneven shape is formed, and the uneven shape is formed on each underlayer. Then, by forming a gold plating layer on each underlayer, the collector electrode 62C and the voltage sense electrode 63C with the uneven shape can be formed.

[0107] Note that, assuming that sandblasting treatment is performed after forming the collector electrode 62C and the voltage sense electrode 63C. In this case, since the film thickness of the gold plating layer of the collector electrode 62C and the voltage sense electrode 63C is about several micrometers, there is a possibility that the gold plating layer is peeled off and the underlayer is exposed by the sandblasting treatment. On the other hand, according to the above method, it is possible to suppress the exposure of the underlayers of the respective collector electrodes 62C and voltage sense electrodes 63C.

[0108] When performing a performance test of the semiconductor test apparatus 1 using the test element 60C configured as described above, the test element 60C is placed on the mounting surface 15 of the semiconductor test apparatus 1. Then, the collector electrode 62C and the stage electrode 12 come into contact, and the sense electrode 13 and the voltage sense electrode 63C come into contact.

[0109] At this time, foreign matter in the clean room may be caught between the mounting surface 15 and the test element 60C. In the test element 60C of the fourth embodiment, since the surfaces of the main surface 68C, the collector electrode 62C, and the voltage sense electrode 63C are formed in an uneven shape, foreign matter easily enters the concave portions.

[0110] As a result, it is possible to suppress a difference from occurring between the contact resistance between the stage electrode 12 and the collector electrode 62C when foreign matter is sandwiched between the mounting surface 15 and the test element 60C and the contact resistance between the stage electrode 12 and the collector electrode 62C when foreign matter is not sandwiched between the mounting surface 15 and the test element 60C. Similarly, it is possible to suppress a difference from occurring in the contact resistance between the sense electrode 13 and the voltage sense electrode 63C.

[0111] Regardless of the presence or absence of foreign matter, since fluctuations in the contact resistance between the stage electrode 12 and the collector electrode 62C can be suppressed, it is possible to suppress fluctuations in the ratio of the amount of current flowing through the current path R1 and the amount of current flowing through the current path R2.

[0112] In this way, by performing a performance test of the semiconductor test apparatus 1 using the test element 60C, the performance of the semiconductor test apparatus 1 can be inspected favorably. Note that the flow for determining the performance test of the semiconductor test apparatus 1 using the test element 60C is the same as that of the first embodiment described above.

[0113] The embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The technical scope shown by the present disclosure is indicated by the scope of claims rather than the above-described embodiments, and it is intended that all modifications within the meaning and scope equivalent to the scope of claims be included.

Explanation of Signs

[0114] 1 Semiconductor test apparatus, 2 Control apparatus, 3 Drive circuit, 10 Stage, 11 Stage body, 12 Electrode 1, 13 Sense electrode, 14 Fixing device, 16 Suction tube, 17 Suction port, 20 Probe assembly, 22 Probe, 24 Control probe, 25 Emitter probe, 26 Voltage sense probe, 27 Current sense probe, 30 Voltage sensor, 40 Constant current source, 50 Current sensor.

Claims

1. A semiconductor test apparatus capable of testing the electrical characteristics of a semiconductor element and evaluating the contact between a probe and a test element using a test element simulating the semiconductor element, wherein the test element comprises a substrate having a first main surface and a second main surface, a positive electrode formed on the first main surface, a negative electrode formed on the second main surface, a negative electrode sense electrode, and a control electrode for controlling the electrical conduction between the positive electrode and the negative electrode in response to a control signal, and the semiconductor test apparatus comprises a stage for fixing the test element, a stage electrode provided on the stage and connected to the positive electrode, a probe unit provided to move up and down toward the stage, a voltage sensor for detecting the voltage between the positive electrode and the negative electrode, a power supply for supplying a current between the positive electrode and the negative electrode, a current sensor for detecting the current between the positive electrode and the negative electrode sense electrode, a control device, and an output unit for outputting an evaluation result, and the probe unit includes a first probe that contacts the negative electrode of the test element fixed to the stage and a second probe that contacts the negative electrode sense electrode of the test element fixed to the stage, wherein the control device stores an appropriate current value calculated based on the tip shape of the first probe, the tip shape of the second probe, a first predetermined pressing pressure expected between the first probe and the negative electrode, and a second predetermined pressing pressure expected between the second probe and the negative electrode sense electrode, and the control device contacts the stage electrode with the positive electrode by fixing the test element to the stage, contacts the first probe with the negative electrode such that the pressing pressure between the first probe and the negative electrode becomes the first predetermined pressing pressure by bringing the probe unit closer to the test element with the test element fixed to the stage, contacts the second probe with the negative electrode sense electrode such that the pressing pressure between the second probe and the negative electrode sense electrode becomes the second predetermined pressing pressure by bringing the probe unit closer to the test element with the test element fixed to the stage, With the stage electrode in contact with the positive electrode, the first probe in contact with the negative electrode, and the second probe in contact with the negative electrode sense electrode, a current is supplied between the positive electrode and the negative electrode. Based on the output value from the current sensor and the appropriate current value, if it is determined that the output value is abnormal, the control device causes the output unit to output an abnormality indicating that there is an abnormality in the contact between the first probe and the negative electrode or in the contact between the second probe and the negative electrode sense electrode. A semiconductor test device.

2. A drive circuit, A voltage sensor that detects the voltage between the positive electrode and the negative electrode, Further comprising a third probe that is connected to the drive circuit and contacts the control electrode, The drive circuit applies a voltage to the control electrode through the third probe. The semiconductor test device according to claim 1.

3. A method for evaluating the performance of a semiconductor test device capable of testing the electrical characteristics of a semiconductor element and evaluating the contact between a probe and a test element using a test element simulating the semiconductor element, The test element is A substrate having a first main surface and a second main surface, A positive electrode formed on the first main surface, A negative electrode formed on the second main surface, a negative electrode sense electrode, and a control electrode that controls the electrical conduction between the positive electrode and the negative electrode in response to a control signal, Including, The semiconductor test device is A stage on which the first main surface is disposed and that fixes the test element, A stage electrode provided on the stage and connected to the positive electrode, A probe unit provided to move up and down toward the stage, A voltage sensor that detects the voltage between the positive electrode and the negative electrode, A power supply that supplies a current between the positive electrode and the negative electrode, A current sensor that detects the current between the positive electrode and the negative electrode sense electrode, A control device, An output unit that outputs an evaluation result, Comprising, The probe unit includes a first probe that contacts the negative electrode of the test element fixed to the stage and a second probe that contacts the negative electrode sense electrode of the test element fixed to the stage. The method for evaluating the performance of the semiconductor test device is A step of storing an appropriate current value calculated based on the tip shape of the first probe, the tip shape of the second probe, a first planned pressing pressure expected between the first probe and the negative electrode, and a second planned pressing pressure expected between the second probe and the negative electrode sense electrode; A step of bringing the stage electrode into contact with the positive electrode by fixing the test element to the stage; A step of bringing the first probe into contact with the negative electrode so that the pressing pressure between the first probe and the negative electrode becomes the first planned pressing pressure by bringing the probe unit closer to the test element with the test element fixed to the stage; A step of bringing the second probe into contact with the negative electrode sense electrode so that the pressing pressure between the second probe and the negative electrode sense electrode becomes the second planned pressing pressure by bringing the probe unit closer to the test element with the test element fixed to the stage; A step of supplying a current between the positive electrode and the negative electrode in a state where the stage electrode is in contact with the positive electrode, the first probe is in contact with the negative electrode, and the second probe is in contact with the negative electrode sense electrode; When it is determined that the output value is abnormal based on the output value from the current sensor and the appropriate current value, the control device causes the output unit to output an abnormality, indicating that there is an abnormality in the contact between the first probe and the negative electrode or the contact between the second probe and the negative electrode sense electrode; A method for evaluating the performance of a semiconductor test device, comprising the above steps.

4. The method for evaluating the performance of a semiconductor test device according to claim 3, wherein the test element includes a first resistor provided between the positive electrode and the negative electrode sense electrode and a second resistor provided between the positive electrode and the negative electrode.

5. The method for evaluating the performance of a semiconductor test device according to claim 3, wherein the test element further includes a first diode provided between the positive electrode and the negative electrode sense electrode and a second diode provided between the positive electrode and the negative electrode.

6. The method for evaluating the performance of a semiconductor test device according to claim 3, wherein the first main surface and the surface of the positive electrode are formed in an uneven shape.

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