Semiconductor testing equipment, semiconductor testing method, and semiconductor device manufacturing method

Abstract

Each of M second constant-current sources (2a, 2b) or M variable resistances (71, 72) causes a current to flow in an amount of 1 / M the sum of currents from N first constant-current sources (1a-1h). Each of N first probes (53a-53h) connects the negative electrode of the corresponding one of N semiconductor elements (27a-27h) to the negative electrode of the corresponding one of the N first constant-current sources (1a-1h). Each of M electrodes (31, 32) is disposed on the periphery of a test stage (51) and is connected to the positive electrode of the corresponding one of the M second constant-current sources (2a, 2b) or M variable resistances (71, 72) to function as a current supply point. A voltage measurement part (3) measures a voltage between at least one collector-sense terminal (33) disposed on the periphery of the test stage (51) and each of the negative electrodes (127a-127h) of N semiconductor elements.

Description

Technical Field

[0001] The present disclosure relates to a semiconductor test apparatus, a semiconductor test method, and a method for manufacturing a semiconductor device.

Background Art

[0002] The product performance of semiconductor elements is guaranteed by performing characteristic tests in the test process during the manufacturing process. The characteristic tests include tests such as applying a high voltage or a large current to the semiconductor element and screening.

[0003] The characteristic tests include tests performed in the state of a module and tests performed in the state of a semiconductor element. In order to reduce the manufacturing cost, it is preferable that the tests can be performed in the state of a wafer. However, there is a problem that the reproducibility of the measurement results is low due to the electrical resistance that changes depending on the contact condition between the test stage on which the wafer is placed and the back surface of the wafer, and the difference in resistance of the path from the test stage to the measurement point.

[0004] Patent Document 1 discloses a configuration for reducing the contact resistance between a test stage and the back surface of a wafer as a test method for a semiconductor transistor. <00000​​​​​​​​​​​​​​​​​​​​​​​​​ However, the test method described in Patent Document 1 has the problem that measurement errors vary across the wafer plane because it cannot eliminate the influence of differences in resistance along the path to the measurement point on the test stage. Furthermore, the test method described in Patent Document 1 cannot measure multiple chips simultaneously.

[0008] Therefore, the object of this disclosure is to provide a semiconductor testing apparatus, a semiconductor testing method, and a semiconductor device manufacturing method that can simultaneously measure multiple chips and reduce variations in measurement errors within the wafer plane during testing of semiconductor devices in a wafer state. [Means for solving the problem]

[0009] The semiconductor test apparatus of this disclosure is for simultaneously testing the characteristics of N (N is a natural number of 2 or more) semiconductor elements, each having a positive electrode on its back surface and a negative electrode and a control electrode on its front surface, which are turned on or off in response to a control signal input to the control electrode, and comprises a test stage that fixes a wafer on which the plurality of semiconductor elements are arranged and has the role of a positive electrode electrically connected to the positive electrodes of the plurality of semiconductor elements, N (N is a natural number of 2 or more) first constant current sources, and M (M is a natural number of 2 or more) first constant current sources, each having a negative electrode connected to the positive electrode of the N first constant current sources. The system comprises two constant current sources or M variable resistors, N first probes, each connecting a corresponding negative electrode of one of N semiconductor elements to a corresponding negative electrode of one of N first constant current sources, M electrodes, each positioned on the outer periphery of the test stage and connected to a corresponding positive electrode of one of M second constant current sources or M variable resistors, functioning as a current supply point, at least one collector-sense terminal positioned on the outer periphery of the test stage, and a voltage measuring unit that measures the voltage between the collector-sense terminal and each of the N negative electrodes of the semiconductor elements. Each of the M second constant current sources or each of the M variable resistors carries a current of 1 / M of the sum of the currents of the N first constant current sources.

[0010] The semiconductor test method of this disclosure is a semiconductor test method using a semiconductor test apparatus for simultaneously testing the characteristics of N (N is a natural number of 2 or more) semiconductor elements, each having a positive electrode on its back surface and a negative electrode and a control electrode on its front surface, which are turned on or off in response to a control signal input to the control electrode. The semiconductor test apparatus comprises a test stage acting as a positive electrode, N (N is a natural number of 2 or more) first constant current sources, M (M is a natural number of 2 or more) second constant current sources or M variable resistors, each having a negative electrode connected to the positive electrode of the N first constant current sources, M electrodes, each arranged on the outer periphery of the test stage and connected to the corresponding positive electrode of one of the M second constant current sources or M variable resistors, functioning as a current supply point, at least one collector sense terminal arranged on the outer periphery of the test stage, a first probe, a second probe, and a voltage measuring unit. The semiconductor test method comprises the steps of: fixing a wafer on which a plurality of semiconductor elements are arranged to a test stage and connecting the positive electrodes of the plurality of semiconductor elements to the test stage; connecting each of N first probes to a corresponding negative electrode of one of the N semiconductor elements and a corresponding negative electrode of one of N first constant current sources; connecting each of N second probes to a corresponding control electrode of one of the N semiconductor elements and a drive circuit; starting the supply of a constant current from the N first constant current sources; starting the supply of a current equal to 1 / M of the sum of the currents of the N first constant current sources from each of the M second constant current sources or each of the M variable resistors; and measuring the voltage between the collector sense terminal and each of the negative electrodes of the N semiconductor elements.

[0011] The method for manufacturing a semiconductor device according to this disclosure comprises the steps of: manufacturing a semiconductor device by a wafer process; testing the manufactured wafer; and commercializing the semiconductor device that has passed the test. The step of testing the wafer uses the semiconductor testing method described above. [Effects of the Invention]

[0012] According to this disclosure, in tests performed on a semiconductor device in wafer form, multiple chips can be measured simultaneously, and variations in measurement errors within the wafer plane can be reduced. [Brief explanation of the drawing]

[0013] [Figure 1] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 1. [Figure 2] This is a simplified diagram of the path for measuring the saturation voltage of the semiconductor element 27 in Embodiment 1. [Figure 3] This is a simplified diagram of the path for measuring the saturation voltage of the semiconductor element 26 in Embodiment 1. [Figure 4] This is a flowchart showing the procedure for testing the saturation voltage of a semiconductor device in Embodiment 1. [Figure 5] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 2. [Figure 6] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 3. [Figure 7] This is a flowchart showing the procedure for testing the saturation voltage of a semiconductor device in Embodiment 3. [Figure 8] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 4. [Figure 9] This is a simplified diagram of the path for measuring the saturation voltage of the semiconductor element 27 in Embodiment 4. [Figure 10] This is a simplified diagram of the path for measuring the saturation voltage of the semiconductor element 26 in Embodiment 4. [Figure 11] This is a flowchart showing the measurement procedure for measuring the saturation voltage in Embodiment 4. [Figure 12] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 5. [Figure 13] This diagram shows the configuration of the semiconductor testing apparatus according to Embodiment 6. [Figure 14] This is a flowchart showing the measurement procedure for measuring the saturation voltage in Embodiment 6. [Figure 15]It is a flowchart showing a method of manufacturing a semiconductor device according to Embodiment 7.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments will be described in detail with reference to the drawings. In the following, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated in principle.

[0015] Embodiment 1. FIG. 1 is a diagram showing the configuration of a semiconductor test device according to Embodiment 1. A test of the collector-emitter saturation voltage (hereinafter referred to as the saturation voltage), which is a typical high-current test, will be described as an example.

[0016] Referring to FIG. 1, the case of simultaneously measuring eight semiconductor elements arranged on a wafer will be described. Eight semiconductor elements 26a to 26h or eight semiconductor elements 27a to 27h are simultaneously measured. The number of simultaneous measurements is not limited to this. In FIG. 1, only four of the semiconductor elements 26a to 26h and 27a to 27h are shown. This semiconductor test device includes a test stage 51, first probes 53a to 53h, second probes 54a to 54h, a drive circuit 55, first constant current sources 1a to 1h, second constant current sources 2a and 2b, a first electrode 31, a second electrode 32, and a collector sense terminal 33.

[0017] The number of the first probes 53a to 53h is the same as the number of semiconductor elements to be simultaneously measured, which is eight. In FIG. 1, only two are shown. The number of the second probes 54a to 54h is the same as the number of semiconductor elements to be simultaneously measured, which is eight. In FIG. 1, only one is shown.

[0018] Test stage 51 fixes the wafer 63. Multiple semiconductor elements are arranged on the wafer 63. Any self-extinguishing semiconductor element can be used as the semiconductor element. All semiconductor elements on the wafer 63, or a portion of all semiconductor elements, are inspected by sampling. Semiconductor elements 27a-h and semiconductor elements 26a-h are representative of the multiple semiconductor elements arranged in the wafer.

[0019] In the following explanation, semiconductor elements 27a to h may be collectively referred to as semiconductor element 27, and semiconductor elements 26a to h may be collectively referred to as semiconductor element 26. The first constant current sources 1a to 1h may be collectively referred to as the first constant current source 1, and the second constant current sources 2a and 2b may be collectively referred to as the second constant current source 2. The first probes 53a to 53h may be collectively referred to as the first probe 53, and the second probes 54a to 54h may be collectively referred to as the second probe 54.

[0020] The semiconductor elements 26 and 27 have a positive electrode on their back surface and a negative electrode and a control electrode on their front surface. The semiconductor elements 26 and 27 are turned on or off in response to a first control signal input from the drive circuit 55 to the control electrode. For example, if the semiconductor elements 26 and 27 are MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), the positive electrode is the drain electrode, the negative electrode is the source electrode, and the control electrode is the gate electrode. If the semiconductor elements 26 and 27 are IGBTs (Insulated Gate Transistors), the positive electrode is the collector electrode, the negative electrode is the emitter electrode, and the control electrode is the gate electrode. The following explanation will use the case where the semiconductor elements 26 and 27 are IGBTs as an example.

[0021] In semiconductor elements 26a~h and 27a~h, current flows from the positive electrode on the back surface to the negative electrode on the front surface. In order to perform characteristic testing of such semiconductor elements 26a~h and 27a~h in the state of wafer 63, the negative electrodes (emitter in the case of IGBTs) on the surface of semiconductor elements 26a~h and 27a~h are electrically connected to the first constant current sources 1a~h by needle-shaped first probes 53a~h. The control electrodes (gate in the case of IGBTs) on the surface of semiconductor elements 26a~h and 27a~h are electrically connected to the drive circuit 55 of the semiconductor testing apparatus by needle-shaped second probes 54a~h. Figure 1 shows the state in which the first probe 53 and the second probe 54 are connected to the semiconductor element 27 when the test subject is semiconductor element 27.

[0022] The positive electrode (collector in the case of an IGBT) on the back surface of the semiconductor elements 26 and 27 is directly electrically connected to the test stage 51 (conductor), which acts as the positive electrode.

[0023] The first constant current sources 1a to 1h and the second constant current sources 2a to 2b supply a constant current. The negative terminals of the second constant current sources 2a to 2b are connected to the positive terminals of the first constant current sources 1a to 1h. The second constant current source 2a supplies a current equal to half the sum of the currents of the first constant current sources 1a to 1h. The second constant current source 2b supplies a current equal to half the sum of the currents of the first constant current sources 1a to 1h.

[0024] The first electrode 31 is positioned on the outer periphery of the test stage 51. The first electrode 31 is connected to the positive electrode of the second constant current source 2a. The first electrode 31 functions as the first current supply point to the test stage 51. The second electrode 32 is positioned on the outer periphery of the test stage 51. The second electrode 32 is connected to the positive electrode of the second constant current source 2b. The first electrode 31 and the second electrode 32 are electrically connected to the positive electrodes on the back surfaces of the semiconductor elements 26 and 27.

[0025] In the saturation voltage test, the on-resistance (equivalent resistance) of semiconductor element 27a is shown by resistor 17a, and the on-resistance (equivalent resistance) of semiconductor element 26a is shown by resistor 16a. The first electrode 31 and the second electrode 32 are positioned on the outer periphery of the test stage 51. It is desirable that the first electrode 31 and the second electrode 32 be positioned on the outer periphery of the test stage 51 at equal angular intervals (i.e., point-symmetrical positions with respect to the center of the test stage 51).

[0026] The positive electrode of the second constant current source 2a is electrically connected to the negative electrode of the second constant current source 2a via the wiring resistor 10, the first electrode 31, the resistor 13, the semiconductor element 27a, and the first constant current source 1a by the first probe 53a.

[0027] The positive electrode of the second constant current source 2a is electrically connected to the negative electrode of the second constant current source 2a via the wiring resistor 10, the first electrode 31, the resistor 12, the semiconductor element 26a, and the first constant current source 1a by the first probe 53a.

[0028] The wiring resistance 10 is the resistance of the electrical wiring between the second constant current source 2a and the first electrode 31.

[0029] The resistance 13 is the sum of the resistance component of the current path flowing through the test stage 51 when power is supplied to the semiconductor element 27 through the first electrode 31, and the contact resistance between the test stage 51 and the positive electrode on the back surface of the semiconductor element 27.

[0030] If the resistance component of the test stage 51 is uniform, current will flow along the shortest distance between the first electrode 31 and the semiconductor element 27. For example, if there is a defect in the test stage 51, current may not flow along the shortest path. The same applies to the resistance component from the other electrodes to the semiconductor element.

[0031] The resistance 12 is the sum of the resistance component of the current path flowing through the test stage 51 when power is supplied to the semiconductor element 26 through the first electrode 31, and the contact resistance between the test stage 51 and the positive electrode on the back surface of the semiconductor element 26.

[0032] The positive electrode of the second constant current source 2b is electrically connected to the negative electrode of the second constant current source 2b via the wiring resistor 11, the second electrode 32, the resistor 14, the semiconductor element 27a, and the first constant current source 1a by the first probe 53a.

[0033] The positive electrode of the second constant current source 2b is connected to the negative electrode of the second constant current source 2b via the wiring resistor 11, the second electrode 32, the resistor 15, the semiconductor element 26a, and the first constant current source 1a by the first probe 53a.

[0034] The wiring resistance 11 is the resistance of the electrical wiring between the second constant current source 2b and the second electrode 32.

[0035] The resistance 14 is the sum of the resistance component of the current path that flows through the test stage 51 when power is supplied to the semiconductor element 27 through the second electrode 32, and the contact resistance between the test stage 51 and the positive electrode on the back surface of the semiconductor element 27.

[0036] The resistance 15 is the sum of the resistance component of the current path flowing through the test stage 51 when power is supplied to the semiconductor element 26 through the second electrode 32, and the contact resistance between the test stage 51 and the positive electrode on the back surface of the semiconductor element 26.

[0037] Strictly speaking, resistor 13 differs between semiconductor elements 27a and 27b. This is because the contact resistance with the test stage 51 differs depending on the condition of the back surface of each semiconductor element, and the current path also differs. For simplicity, it is written as resistor 13, but it may be assumed that there are resistors 13a to h corresponding to semiconductor elements 27a to h. The same applies to resistors 12, 14, and 15.

[0038] The equivalent resistance of semiconductor element 27a when its saturation voltage is measured is the on-resistance 17a. The equivalent resistance of semiconductor element 26a when its saturation voltage is measured is the on-resistance 16a. For example, when the current of the first constant current source 1a is 50A and the saturation voltage of semiconductor element 27a is 1V, the on-resistance 17a is 0.02Ω.

[0039] The collector of the semiconductor element and the wafer 63 are electrically connected by the back surface of the semiconductor element contacting the wafer 63. The front surface of the semiconductor element has a gate electrode (not shown) and an emitter electrode. Semiconductor elements 27a to h have emitter electrodes 127a to h, and semiconductor elements 26a to h have emitter electrodes 126a to h.

[0040] The first probe 53a and the emitter electrode 127a of the semiconductor element 27a are electrically connected.

[0041] The collector sense terminal 33 is positioned on the outer periphery of the test stage 51. The collector sense terminal 33 is positioned closer to the first electrode 31 than to the second electrode 32. It is more desirable for the collector sense terminal 33 to be positioned in the vicinity of the first electrode 31. The collector sense terminal 33 is electrically connected to the positive electrode on the back surface of the semiconductor elements 26 and 27.

[0042] The voltage measurement unit 3 measures the voltage between the collector sense terminal 33 and the emitter electrodes 127a to h. It is desirable that the voltage measurement unit 3 be equipped with eight parallel voltmeters so that eight voltages can be measured simultaneously. Alternatively, the voltage measurement unit 3 may be configured to measure the voltage between the collector sense terminal 33 and the emitter electrodes 127a to h of eight semiconductor elements by switching a switch. The latter configuration can reduce the price of the semiconductor testing equipment.

[0043] The saturation voltage of the semiconductor element 27 can be measured at four terminals using the second constant current source 2 and the voltage measurement unit 3. Since only a small current flows between the collector sense terminal 33 and the first electrode 31, and the electrical resistance at the two points between the conductors is also small, the collector sense terminal 33 and the first electrode 31 can be considered to be at the same potential.

[0044] By arbitrarily moving the test stage 51, the needle-shaped first probe 53 and the second probe 54 can be electrically brought into contact with any semiconductor element on the wafer 63.

[0045] The first constant current sources 1a to 1h supply a constant current to semiconductor elements 26a to 26h or semiconductor elements 27a to 27h. The second constant current sources 2a to 2b supply a constant current to semiconductor elements 26a to 26h or semiconductor elements 27a to 27h. The second constant current source 2a supplies a constant current equal to half the sum of the currents from the first constant current sources 1a to 1h. The second constant current source 2b supplies a constant current equal to half the sum of the currents from the first constant current sources 1a to 1h.

[0046] When measuring the saturation voltage of the semiconductor element 27a, the drive circuit 55 turns on the semiconductor element 27a by applying a voltage to the control electrode of the semiconductor element 27a through the second probe 54a. The saturation voltage of the semiconductor element 27a can be measured by bringing the first probe 53a into contact with the negative electrode on the surface of the semiconductor element 27a and measuring the voltage between the collector sense terminal 33 and the emitter electrode 127a of the semiconductor element 27a using the voltage measuring unit 3.

[0047] When measuring the saturation voltage of the semiconductor element 26a, the drive circuit 55 turns on the semiconductor element 26 by applying a voltage to the control electrode of the semiconductor element 26a through the second probe 54a. The saturation voltage of the semiconductor element 26a can be measured by bringing the first probe 53a into contact with the emitter electrode 126a on the surface of the semiconductor element 26a and measuring the voltage between the collector sense terminal 33 and the emitter electrode 126a of the semiconductor element 26a using the voltage measurement unit 3.

[0048] It is preferable that the first electrode 31 and the second electrode 32 are positioned point-symmetrically from the center of the test stage 51. Assuming that the resistance of the test stage 51 is uniform, and neglecting the contact resistance between the positive electrode on the back surface of the semiconductor element and the test stage 51, the magnitudes of resistances 12, 13, 14, and 15 are proportional to the distance from the electrode to the semiconductor element. If the first electrode 31 and the second electrode 32 are positioned point-symmetrically from the center of the test stage 51, then when the semiconductor element 26 and the semiconductor element 27 are positioned point-symmetrically from the center of the test stage 51, the values ​​of resistance 13 and resistance 15 will be the same, and the values ​​of resistance 14 and resistance 12 will be the same, so the saturation voltage of semiconductor element 26 and the saturation voltage of semiconductor element 27 will be the same. However, even if they are not point-symmetric, it is possible to reduce the variation in the measurement error of the saturation voltage within the wafer 63 surface caused by semiconductor test equipment such as resistance 13.

[0049] Figure 2 is a simplified diagram of the path for measuring the saturation voltage of semiconductor element 27 in Embodiment 1. Figure 3 is a simplified diagram of the path for measuring the saturation voltage of semiconductor element 26 in Embodiment 1.

[0050] Referring to Figures 2 and 3, we will explain how to calculate the measured value of the saturation voltage (also called Vce(sat)), which is a common high-current test. Since calculations using variables would be complicated, we will substitute real numbers for the resistance values ​​here. In the following, the semiconductor elements 26 and 27 of the test will be described as IGBTs.

[0051] The positional relationship between semiconductor element 27a and semiconductor element 26a is assumed to be point-symmetric with respect to the center point of the test stage 51. The positional relationship between the first electrode 31 and the second electrode 32 is assumed to be point-symmetric with respect to the center point of the test stage 51.

[0052] Assume that the saturation voltages of semiconductor elements 26a and 27a are the same. Assume that the wiring resistance 10 is 0.1Ω, wiring resistance 11 is 0.11Ω, resistance 12 is 0.001Ω, resistance 13 is 0.0005Ω, resistance 14 is 0.001Ω, resistance 15 is 0.0005Ω, resistances 16a~h are 0.007Ω, and resistances 17a~h are 0.007Ω.

[0053] When a constant voltage, such as 15V, is applied to the gate of the semiconductor element 27a to turn it on, and a large current, such as 50A, is passed through the collector of the semiconductor element 27a, the collector-emitter voltage of the semiconductor element 27a is the saturation voltage of the semiconductor element 27a. However, since it is difficult to directly measure the voltage between the collector electrode and the emitter electrode of the semiconductor element 27a, in a typical saturation voltage test, the voltage between the collector sense terminal 33 and the emitter electrode 127a of the semiconductor element 27a is measured and taken as the saturation voltage of the semiconductor element 27a. This saturation voltage is a value that includes the voltage drop across the resistor 13.

[0054] In typical conventional saturation voltage tests, there is one second constant current source 2, and the current is supplied at one or two points. When there is one current supply point, the further the semiconductor element is from the supply point, the greater the resistance of the test stage 51, causing the measured saturation voltage to be higher than the true value. Therefore, when there is one current supply point, there is variation in the measurement error of the saturation voltage of the semiconductor element across the wafer 63. When there are two current supply points, current is supplied from one constant current source through two divided current paths, so the current becomes unbalanced unless the sum of the wiring resistance and the resistance of the test stage is equal in the two current paths. However, since the resistance of the test stage fluctuates depending on the position of the semiconductor element, it is difficult to make the resistances of the two current paths equal.

[0055] In this embodiment, the second constant current sources 2a and 2b can, for example, constantly supply half of the desired current (400A in this case), which is 200A, to the first electrode 31, thereby reducing the measurement error due to the resistor 13 by half. As a result, the variation in the measurement error of the saturation voltage of the semiconductor element caused by the above-mentioned current across the wafer 63 can be reduced.

[0056] In the case of the resistance values ​​shown in Figure 2, if the current flowing through the collectors of semiconductor elements 27a to 27b is 400A, then 1 / 8 of that, or 50A, flows through semiconductor element 27a. The saturation voltage of semiconductor element 27a is 0.45V. In the case of the resistance values ​​shown in Figure 3, the saturation voltage of semiconductor element 26a is 0.55V. In Figures 2 and 3, when there is only one constant current source, a current of 400A flows through resistors 12 and 13, so the saturation voltage of semiconductor element 27a is 0.55V and the saturation voltage of semiconductor element 26a is 0.75V. In this embodiment, the second constant current sources 2a and 2b reduce measurement errors and reduce the difference in saturation voltages between semiconductor elements 27a and 26a, that is, the in-plane distribution is improved.

[0057] Figure 4 is a flowchart showing the procedure for testing the saturation voltage of a semiconductor device in Embodiment 1.

[0058] In step S02, the semiconductor test apparatus is connected to the multiple semiconductor elements of the test subject. For example, if the test subject is semiconductor elements 27a to h, the emitters on the surface of semiconductor elements 27a to h are electrically connected to the negative electrodes of the first constant current sources 1a to h by needle-shaped first probes 53a to h. The gates on the surface of semiconductor elements 27a to h are electrically connected to the drive circuit 55 of the semiconductor test apparatus by needle-shaped second probes 54a to h. The collectors on the back surface of semiconductor elements 27a to h are directly electrically connected to the test stage 51 (conductor), which acts as the positive electrode.

[0059] In step S03, the drive circuit 55 turns on the semiconductor elements 27a to h of the test subject.

[0060] In step S04, the supply of current from the semiconductor test equipment is started. The first constant current sources 1a to 1h start supplying a constant current. The second constant current source 2a starts supplying a current equal to half the sum of the currents from the first constant current sources 1a to 1h. The second constant current source 2b starts supplying a current equal to half the sum of the currents from the first constant current sources 1a to 1h.

[0061] In step S041, the voltage measurement unit 3 measures the saturation voltage of the semiconductor elements 27a to h by measuring the voltage between the collector sense terminal 33 and the emitter electrodes of the semiconductor elements 27a to h.

[0062] In step S05, if the measured saturation voltage is within the specifications, the process proceeds to S06. If the measured saturation voltage is outside the specifications, the process proceeds to step S07.

[0063] In step S06, the semiconductor elements 27a to h of the test subject are judged to be acceptable. In step S07, the semiconductor elements 27a to h of the test subject are determined to be unacceptable. If unacceptable, for example, the semiconductor element of the test subject may be marked with ink. Alternatively, the pass or fail status may be recorded electronically.

[0064] After steps S06 and S07, the process proceeds to step S08. In step S08, the supply of current from the semiconductor test apparatus is stopped. That is, the output of current from the first constant current sources 1a to h and the second constant current sources 2a to b is stopped. The drive circuit 55 turns off the semiconductor elements 27a to h of the test subject.

[0065] In step S09, the connection between the semiconductor test apparatus and the semiconductor elements 27a to h of the test subject is disconnected.

[0066] In step S10, the test stage 51 moves to the measurement position of the next semiconductor element. The process in steps S01 to S10 is repeated until all semiconductor elements on the wafer 63 have been measured. Alternatively, in the case of a sampling test, only the semiconductor elements at predetermined positions are measured.

[0067] As described above, according to the semiconductor testing apparatus and semiconductor testing method of Embodiment 1, since the currents flowing through the first electrode 31 and the second electrode 32 are the same, it is possible to reduce the in-plane variation of measurement errors on the wafer 63 in high-current tests such as the saturation voltage measurement of semiconductor elements.

[0068] Embodiment 2. The true value of the saturation voltage of the semiconductor element 27 is equal to the voltage across the resistor 17. However, it is difficult to directly measure the potential between the collector electrode and emitter electrode of the semiconductor element 27. Therefore, in Embodiment 1, the voltage between the collector sense terminal 33 and the negative electrodes of the first constant current sources 1a to h is measured, and this is taken as the saturation voltage of the semiconductor element 27.

[0069] The resistance component in the path from resistor 17 to the negative electrode of the first constant current source 1 causes the saturation voltage of the semiconductor element 27 to deviate from its true value. To reduce this deviation, the resistance component must be lowered. In Embodiment 1, by using two constant current sources and two current supply points, the current flowing through the first electrode 31 is halved. This reduces the voltage drop due to resistor 13 by half.

[0070] In this embodiment, there are M second current sources and M current supply points, where M is a natural number greater than or equal to 3. The M electrodes are arranged on the outer circumference of the test stage 51 at equal angular intervals. Each of the M electrodes is connected to a corresponding one of the M second constant current sources, functioning as one of the M current supply points.

[0071] Figure 5 shows the configuration of the semiconductor test apparatus of Embodiment 2. Figure 5 shows the case where M=4. This semiconductor test apparatus further includes a second constant current source 2c, a second constant current source 2d, a third electrode 131, and a fourth electrode 132, in addition to the configuration of the semiconductor test apparatus of Embodiment 1. Resistor 110 is the resistance of the electrical wiring between the second constant current source 2c and the third electrode 131. Resistor 111 is the resistance of the electrical wiring between the second constant current source 2d and the fourth electrode 132. The illustration of the resistance components within the test stage 51 is omitted.

[0072] The first electrode 31 is connected to the positive electrode of the second constant current source 2a. The second electrode 32 is connected to the positive electrode of the second constant current source 2b. The third electrode 131 is connected to the positive electrode of the second constant current source 2c. The fourth electrode 132 is connected to the positive electrode of the second constant current source 2d. The first electrode 31, the third electrode 131, the second electrode 32, and the fourth electrode 132 are arranged on the outer circumference of the test stage 51 at 90° intervals.

[0073] According to this embodiment, since the current flowing through the first electrode 31 is 1 / M, the voltage drop due to the resistor 13 is reduced to 1 / M. Therefore, the deviation of the saturation voltage from the true value due to the resistor 13 can be reduced to 1 / M. As a result, the measurement error due to the resistor 13 can be reduced to 1 / M.

[0074] Embodiment 3. Figure 6 shows the configuration of the semiconductor test apparatus of Embodiment 3. The difference between the semiconductor test apparatus of Embodiment 3 and the semiconductor test apparatus of Embodiment 1 is that the semiconductor test apparatus of Embodiment 3 is equipped only with a first constant current source 1, and is equipped with a first variable resistor 71, a second variable resistor 72, a first ammeter 81, and a second ammeter 82.

[0075] The first terminal of the first variable resistor 71 is connected to the positive terminal of the first constant current sources 1a to 1h, and the second terminal of the first variable resistor 71 is connected to the first electrode 31. The first terminal of the second variable resistor 72 is connected to the positive terminal of the first constant current sources 1a to 1h, and the second terminal of the second variable resistor 72 is connected to the second electrode 32.

[0076] The first ammeter 81 is connected in series with the first variable resistor 71. The second ammeter 82 is connected in series with the second variable resistor 72. The first ammeter 81 measures the current flowing through the first variable resistor 71. The second ammeter 82 measures the current flowing through the second variable resistor 72. Instead of the first ammeter 81 and the second ammeter 82, an oscilloscope may be used to measure the transient voltage of the current transformer. The resistance values ​​of the variable resistors 71 and 72 are adjusted so that the currents flowing through the first electrode 31 and the second electrode 32 are equal.

[0077] Figure 7 is a flowchart showing the procedure for saturation voltage testing of a semiconductor device in Embodiment 3.

[0078] The difference between the flowchart of Embodiment 3 and the flowchart of Embodiment 2 is that the flowchart of Embodiment 3 includes step S04a instead of step S04.

[0079] In step S04a, the supply of current from the semiconductor test apparatus is started. The first constant current sources 1a to 1h start supplying constant current. The magnitude of the current flowing through the first variable resistor 71 is measured by the first ammeter 81. The magnitude of the current flowing through the second variable resistor 72 is measured by the second ammeter 82. The resistance values ​​of the first variable resistor 71 and the second variable resistor 72 are adjusted so that the values ​​of the first ammeter 81 and the second ammeter 82 are equal. The first variable resistor 71 starts supplying a current equal to half the sum of the currents from the first constant current sources 1a to 1h. The second variable resistor 72 starts supplying a current equal to half the sum of the currents from the first constant current sources 1a to 1h.

[0080] In this embodiment, by making the magnitude of the current flowing through the first electrode 31 equal to the magnitude of the current flowing through the second electrode 32, it is possible to reduce the variation in measurement errors within the wafer 63 during high-current tests such as saturation voltage measurement.

[0081] Modification 1 of Embodiment 3. In this modified example, the magnitude of the resistance component between the semiconductor element under test and the first electrode 31, and the resistance component between the semiconductor element under test and the second electrode 32 are determined in advance. For example, an in-plane voltage drop distribution is created on a wafer where the resistance value of the semiconductor element is known, such as a TEG (Test Element Group) wafer. Since the current value and the resistance value of the semiconductor element are known, the resistance component between the semiconductor element under test and the first electrode 31, and the resistance component between the semiconductor element under test and the second electrode 32 can be determined.

[0082] Modification 2 of Embodiment 3. By making the magnitudes of the first variable resistor 71 and the second variable resistor 72 equal, and by making the magnitudes of the first variable resistor 71 and the second variable resistor 72 sufficiently large compared to the resistance component of the current path on the test stage, such as the wiring resistance 10, and the contact resistance between the semiconductor element and the test stage, a constant current of 1 / 2 can be achieved. However, if the resistance value is large, the capacity of the constant current source of the semiconductor test equipment will increase, leading to increased costs. It is necessary to understand the resistance values ​​of the semiconductor element and the semiconductor test equipment and set appropriate resistance values.

[0083] By adjusting the magnitudes of the first variable resistor 71 and the second variable resistor 72 so that the currents flowing through the first electrode 31 and the second electrode 32 are always equal, the same effect as in Embodiment 3 can be obtained.

[0084] Modification 3 of Embodiment 3. As in Embodiment 2, there may be M variable resistors and M current supply points, where M is a natural number greater than or equal to 3. The M electrodes are arranged on the outer circumference of the test stage 51 at equal angular intervals. Each of the M electrodes is connected to a corresponding one of the M variable resistors and functions as one of the M current supply points. By measuring the current flowing through each of the M variable resistors 71 using an ammeter and adjusting the resistance value of each of the M variable resistors 71, each of the M variable resistors 71 may be configured to supply a current of 1 / M of the sum of the currents from the first constant current sources 1a to 1h.

[0085] Embodiment 4. Figure 8 shows the configuration of the semiconductor test apparatus of Embodiment 4. The difference between the semiconductor test apparatus of Embodiment 4 and the semiconductor test apparatus of Embodiment 1 is that the semiconductor test apparatus of Embodiment 4 is equipped with a collector sense terminal 34, and instead of a voltage measurement unit 3, it is equipped with a voltage measurement unit 3a and a calculation unit 69.

[0086] The collector sense terminal 34 is positioned closer to the second electrode 32 than to the first electrode 31. It is more desirable for the collector sense terminal 34 to be positioned near the second electrode 32. The collector sense terminal 34 is electrically connected to the positive electrode on the back surface of the semiconductor elements 26 and 27.

[0087] The voltage measurement unit 3a measures the voltage Vce(sat)Aa~h between the collector sense terminal 33 and the emitter electrodes 127a~h. Simultaneously, the voltage measurement unit 3a measures the voltage Vce(sat)Ba~h between the collector sense terminal 34 and the emitter electrodes 127a~h.

[0088] Assume that the collector sense terminal 34 and the second electrode 32 are at the same potential. The arithmetic unit 69 calculates the saturation voltage Vce(sat) of the semiconductor element by calculating the measured voltages Vce(sat)Aa~h and Vce(sat)Ba~h. For example, the arithmetic unit 69 can obtain the saturation voltage Vce(sat)a~h of the semiconductor element by averaging Vce(sat)Aa~h and Vce(sat)Ba~h.

[0089] Figure 9 is a simplified diagram of the path for measuring the saturation voltage of semiconductor element 27 in Embodiment 4. Figure 10 is a simplified diagram of the path for measuring the saturation voltage of semiconductor element 26 in Embodiment 4.

[0090] Referring to Figures 9 and 10, we will explain how to calculate the measured value of saturation voltage, a common high-current test. Since calculations using variables would be complicated, we will substitute real numbers for the resistance values ​​here. That is, we will assume that resistor 10 is 0.1Ω, resistor 11 is 0.11Ω, resistor 12 is 0.001Ω, resistor 13 is 0.0005Ω, resistor 14 is 0.001Ω, resistor 15 is 0.0005Ω, resistors 16a~h are 0.007Ω, and resistors 17a~h are 0.007Ω. These are the same resistance values ​​as in Figures 2 and 3.

[0091] Assume that the resistance of the test stage 51 is uniform, and that the contact resistance between the positive electrode on the back surface of the wafer 63 and the test stage 51 is uniform. If the positional relationship between semiconductor element 27 and the first electrode 31, and the positional relationship between semiconductor element 26 and the second electrode 32, as in the case of semiconductor element 26 and semiconductor element 27, are point-symmetric with respect to the center point of the test stage 51, then the magnitude of resistance 13 and the magnitude of resistance 14 will be the same.

[0092] In actual test equipment, the resistance component of the test stage 51 is not uniform, nor is the electrical contact resistance between the positive electrode on the back surface of the wafer 63 and the test stage 51 uniform. Therefore, the magnitude of resistance 13 and the magnitude of resistance 14 will differ depending on the position of the semiconductor element on the wafer 63. In this embodiment, the variation in the magnitude of resistance 13 and the magnitude of resistance 14 can be reduced by, for example, averaging two measured values, Vce(sat)Aa~h and Vce(sat)Ba~h.

[0093] The arithmetic unit 69 may change the method for determining the saturation voltage Vce(sat)a~h of the semiconductor element from the measured values ​​Vce(sat)Aa~h and Vce(sat)Ba~h, depending on the position of the semiconductor element.

[0094] For example, a weighting method may be used based on the difference in distance between the semiconductor element and the two electrodes.

[0095] Alternatively, if the distance from the semiconductor element 27 to the first electrode 31 is half the distance from the semiconductor element 27 to the second electrode 32, the measured value Vce(sat)Aa~h is considered to be closer to the true value because it is less affected by path resistance than the measured value Vce(sat)Ba~h. Therefore, the calculation unit 69 may use the measured value Vce(sat)Aa~h as the saturation voltage Vce(sat)a~h of the semiconductor element 27a~h.

[0096] Figure 11 is a flowchart showing the measurement procedure for saturation voltage measurement in Embodiment 4. The difference between the flowchart of Embodiment 4 and the flowchart of Embodiment 1 is that the flowchart of Embodiment 4 includes step S041a instead of step S041.

[0097] In step S041a, the voltage measurement unit 3a measures the voltage Vce(sat)Aa~h between the collector sense terminal 33 and the emitter electrodes 127a~h. The voltage measurement unit 3a also measures the voltage Vce(sat)Ba~h between the collector sense terminal 34 and the emitter electrodes 127a~h. For example, the arithmetic unit 69 can determine the saturation voltage Vce(sat)a~h of the semiconductor elements 27a~h under test by calculating (for example, averaging) these measured values.

[0098] As described above, according to the semiconductor testing apparatus and semiconductor testing method of Embodiment 4, the current flowing through the first electrode 31 and the second electrode 32 is constant, and by calculating the saturation voltage from the two measured values, it is possible to reduce the variation in measurement errors within the wafer 63 during high-current testing.

[0099] Embodiment 5. The true value of the saturation voltage of semiconductor element 27 is equal to the voltage across resistor 17. However, it is difficult to directly measure the potential between the collector electrodes and emitter electrodes of semiconductor elements 27a to h. Therefore, in Embodiment 4, the voltage between the collector sense terminal 33, which is at the same potential as the first electrode 31, and the emitter electrodes 127a to h is measured, and the voltage between the collector sense terminal 34, which is at the same potential as the second electrode 32, and the emitter electrodes 127a to h is measured. The two measured values ​​are then calculated and taken as the saturation voltage of semiconductor elements 27a to h.

[0100] The resistance component in the path from resistor 17 to emitter electrode 127 causes the saturation voltage of semiconductor elements 27a to h to deviate from the true value, and the only way to reduce this deviation is to lower the resistance component. In Embodiment 4, by providing two second constant current sources and two current supply points, the current flowing through the first electrode 31 is halved. This makes it possible to reduce the voltage drop due to resistor 13 by half.

[0101] In this embodiment, there are M second constant current sources, M current supply points, and M collector sense terminals. N is a natural number greater than or equal to 3.

[0102] The M electrodes are arranged on the outer circumference of the test stage 51 at equal angular intervals. Each of the M electrodes is connected to a corresponding one of the M second constant current sources 2, functioning as one of the M current supply points. Each of the M collector-sense terminals is positioned so that its distance from its corresponding electrode among the M electrodes is shorter than its distance from all other electrodes of the M electrodes combined.

[0103] Figure 12 shows the configuration of the semiconductor test apparatus of Embodiment 5. Figure 12 shows the case where M=4. In addition to the configuration of the semiconductor test apparatus of Embodiment 4, this semiconductor test apparatus further includes a second constant current source 2c, a second constant current source 2d, a third electrode 131, a fourth electrode 132, a collector sense terminal 133, and a collector sense terminal 134. Resistor 110 is the resistance of the electrical wiring between the second constant current source 2c and the third electrode 131. Resistor 111 is the resistance of the electrical wiring between the second constant current source 2d and the fourth electrode 132. The illustration of the resistance components within the test stage 51 is omitted.

[0104] The first electrode 31 is connected to the positive electrode of the second constant current source 2a. The second electrode 32 is connected to the positive electrode of the second constant current source 2b. The third electrode 131 is connected to the positive electrode of the second constant current source 2c. The fourth electrode 132 is connected to the positive electrode of the second constant current source 2d. The first electrode 31, the third electrode 131, the second electrode 32, and the fourth electrode 132 are arranged on the outer circumference of the test stage 51 at 90° intervals.

[0105] The collector sense terminal 33 is positioned so that it is closer to electrode 31 than to electrodes 32, 131, and 132. The collector sense terminal 133 is positioned so that it is closer to electrode 131 than to electrodes 31, 32, and 132. The collector sense terminal 34 is positioned so that it is closer to electrode 32 than to electrodes 31, 131, and 132. The collector sense terminal 134 is positioned so that it is closer to electrode 132 than to electrodes 31, 32, and 131.

[0106] As a result, the current flowing through the first electrode 31 becomes 1 / M, and the voltage drop across resistor 13 is reduced to 1 / M. Therefore, the deviation of the saturation voltage from the true value caused by resistor 13 can be reduced to 1 / M.

[0107] Embodiment 6. Figure 13 shows the configuration of the semiconductor testing apparatus according to Embodiment 6.

[0108] The semiconductor test apparatus of Embodiment 6 differs from the semiconductor test apparatus of Embodiment 5 in the position of collector sense terminals 33, 34, 133, and 134.

[0109] The collector sense terminal 33 is located on the outer circumference of the test stage 51, equidistant from the positions of electrode 31 and electrode 132. The collector sense terminal 134 is located on the outer circumference of the test stage 51, equidistant from the positions of electrode 132 and electrode 32. The collector sense terminal 34 is located on the outer circumference of the test stage 51, equidistant from the positions of electrode 32 and electrode 131. The collector sense terminal 133 is located on the outer circumference of the test stage 51, equidistant from the positions of electrode 131 and electrode 31.

[0110] In Embodiment 5, the electrode 31 and the collector sense terminal 33 were considered to be at the same potential, but by separating the current application point and the voltage measurement point, they are no longer at the same potential.

[0111] By changing which voltage is used at collector sense terminals 33, 34, 133, and 134 depending on the position of the semiconductor element, the effect of voltage drop due to the resistive component of the test stage 51 can be eliminated.

[0112] For example, consider the case of measuring semiconductor elements 27a to h. Since the collector sense terminal 33 is located close to the semiconductor elements 27a to d and is not affected by the electrodes 31, 32, 132, and 133 through which current flows, the arithmetic unit 69 can adopt the measurement result of the voltage Vce between the collector sense terminal 33 and the emitter electrodes 127a to h. The measured value of the voltage Vce between other collector sense terminals, such as collector sense terminal 134 and emitter electrodes 127a to h, will have a large voltage drop because it overlaps with the current flowing from electrode 132 toward semiconductor elements 27a to d. The same applies to other collector sense terminals. The arithmetic unit 69 stores the wafer map information. Using this map information, the arithmetic unit 69 adopts one of the measured values ​​of the voltage Vce between collector sense terminals 33, 334, 133, and 134 and emitter electrodes 127a to h, depending on the position of the semiconductor element. The arithmetic unit 69 can determine the saturation voltage Vce(sat)a~h of the semiconductor element 27a~h as the voltage between the collector sense terminal closest to the semiconductor element 27a~h and the emitter electrode 127a~h.

[0113] Alternatively, the arithmetic unit 69 can determine the smallest measured voltage Vce between the collector sense terminals 33, 334, 133, 134 and the emitter electrodes 127a to h as the saturation voltage Vce(sat)a to h of the semiconductor element 27a to h under test. This is based on the idea that the resistance component of the test stage 51 is proportional to the distance, but in reality, this may not be the case due to scratches or other factors.

[0114] Figure 14 is a flowchart showing the measurement procedure for saturation voltage measurement in Embodiment 6. The difference between the flowchart of Embodiment 6 and the flowchart of Embodiment 1 is that the flowchart of Embodiment 6 includes step S041b instead of step S041.

[0115] In step S041b, the voltage measurement unit 3a measures the voltage Vce(sat)Aa~h between the collector sense terminal 33 and the emitter electrodes 127a~h. The voltage measurement unit 3a measures the voltage Vce(sat)Ba~h between the collector sense terminal 34 and the emitter electrodes 127a~h. The voltage measurement unit 3a measures the voltage Vce(sat)Ca~h between the collector sense terminal 133 and the emitter electrodes 127a~h. The voltage measurement unit 3a measures the voltage Vce(sat)Da~h between the collector sense terminal 134 and the emitter electrodes 127a~h.

[0116] The arithmetic unit 69 uses the map information to select one of these measured values ​​as the saturation voltage Vce(sat)a~h of the semiconductor element 27a~h under test. For example, the arithmetic unit 69 can refer to the map information and determine the voltage between the collector sense terminal closest to the semiconductor element 27a~h and the emitter electrode 127a~h as the saturation voltage Vce(sat)a~h of the semiconductor element 27a~h under test. Alternatively, the arithmetic unit 69 can determine the smallest measured value among these measured values ​​as the saturation voltage Vce(sat)a~h of the semiconductor element 27a~h under test.

[0117] Embodiment 7. Embodiment 7 describes a method for manufacturing a semiconductor device comprising semiconductor elements 26 and 27 as described in Embodiments 1 to 6 above. In other words, Embodiment 7 describes a method for manufacturing a semiconductor device that includes the semiconductor testing method described in Embodiments 1 to 6 as part of the manufacturing process.

[0118] Figure 15 is a flowchart illustrating the manufacturing method of the semiconductor device according to Embodiment 7. In step S101, semiconductor devices are fabricated using a wafer process.

[0119] In step S102, the fabricated wafer is tested. In this test, the semiconductor device test methods shown in Embodiments 1 to 6 are carried out. Further tests, such as dynamic characteristics tests, may be added.

[0120] In step S103, semiconductor devices that have passed the test are commercialized. In this step, if the product is shipped as a wafer, it is diced into individual semiconductor device pieces; if it is shipped as a semiconductor device, the semiconductor devices are mounted onto modules before shipment.

[0121] Within the scope of the invention, this disclosure allows for the combination of each embodiment, and enables the modification or omission of each embodiment as appropriate.

[0122] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than the foregoing description, and all modifications within the meaning and scope of the claims are intended to be included. [Explanation of Symbols]

[0123] 1a~h First constant current source, 2a~d Second constant current source, 3,3a Voltage measurement section, 10,11,12,13,13a,14,15,16a,17,17a,110,111 Resistors, 26a~h,27a~h Semiconductor elements, 31,32,131,132 Electrodes, 33,34,133,134 Collector sense terminals, 51 Test stage, 53a~h First probe, 54a~h Second probe, 55 Drive circuit, 63 Wafer, 69 Processing unit, 71,72 Variable resistors, 81,82 Ammeter, 126a~h,127a~h Emitter electrode.

Claims

1. A semiconductor testing apparatus for simultaneously testing the characteristics of N (where N is a natural number of 2 or more) semiconductor elements, each having a positive electrode on its back surface and a negative electrode and a control electrode on its front surface, which are switched on or off in response to a control signal input to the control electrode, A test stage that fixes a wafer on which multiple semiconductor elements are arranged and also serves as a positive electrode electrically connected to the positive electrodes of the multiple semiconductor elements, N (where N is a natural number greater than or equal to 2) first constant current sources, M (where M is a natural number of 2 or more) second constant current sources or M variable resistors, each having a negative electrode connected to the positive electrode of N first constant current sources, Each of the N first probes connects a corresponding negative electrode from among the N semiconductor elements to a corresponding negative electrode from among the N first constant current sources, Each of the M electrodes is positioned on the outer periphery of the test stage and is connected to the corresponding positive electrode of one of the M second constant current sources or the M variable resistors, and functions as a current supply point. At least one collector sense terminal is located on the outer periphery of the test stage, The system includes a voltage measuring unit that measures the voltage between the collector sense terminal and each of the N semiconductor elements' negative electrodes, A semiconductor testing apparatus in which each of the M second constant current sources or each of the M variable resistors carries a current of 1 / M of the sum of the currents of the N first constant current sources.

2. The semiconductor testing apparatus according to claim 1, each comprising N second probes, each connecting a corresponding control electrode from among the N semiconductor elements to a drive circuit.

3. The semiconductor testing apparatus according to claim 1, wherein the M electrodes are arranged on the outer circumference of the test stage at equal angular intervals.

4. The semiconductor testing apparatus according to claim 1 or 2, wherein the M electrodes are configured to be movable on the outer circumference.

5. The aforementioned at least one collector sense terminal includes M collector sense terminals, Each of the M collector sense terminals is closer to a corresponding electrode among the M electrodes than to all the other electrodes of the M electrodes. The semiconductor testing apparatus according to any one of claims 1 to 3, wherein the voltage measuring unit measures the voltage between each of the M collector sense terminals and each of the N negative electrodes of the semiconductor elements.

6. The semiconductor testing apparatus according to claim 5, further comprising a calculation device that averages the M voltages measured for each of the N semiconductor elements at the M collector sense terminals by the voltage measuring unit.

7. Each unit is equipped with M ammeters for measuring the current flowing through the M variable resistors, The semiconductor testing apparatus according to any one of claims 1 to 3, wherein the resistance values ​​of the M variable resistors are adjusted so that the currents flowing through the M electrodes are equal.

8. The aforementioned at least one collector sense terminal includes M collector sense terminals, Each of the M collector sense terminals is positioned at an equal distance from the positions of two adjacent electrodes among the M electrodes. The semiconductor testing apparatus according to any one of claims 1 to 3, wherein the voltage measuring unit measures the voltage between each of the M collector sense terminals and each of the N negative electrodes of the semiconductor elements.

9. The semiconductor testing apparatus according to claim 8, further comprising a calculation device that calculates the minimum value among the M voltages measured at the M collector sense terminals for each of the N semiconductor elements as the saturation voltage of the semiconductor element.

10. The semiconductor testing apparatus according to claim 8, further comprising a calculation device that calculates, for each of the N semiconductor elements, the voltage measured at the collector sense terminal closest to the semiconductor element out of the M voltages measured at the M collector sense terminals, as the saturation voltage of the semiconductor element.

11. A semiconductor testing method using a semiconductor testing apparatus for simultaneously testing the characteristics of N (where N is a natural number of 2 or more) semiconductor elements, each having a positive electrode on its back surface and a negative electrode and a control electrode on its front surface, which are switched on or off in response to a control signal input to the control electrode, The semiconductor test apparatus comprises a test stage acting as a positive electrode, N (where N is a natural number of 2 or more) first constant current sources, M (where M is a natural number of 2 or more) second constant current sources or M variable resistors, each having a negative electrode connected to the positive electrode of the N first constant current sources, M electrodes, each arranged on the outer periphery of the test stage and connected to the corresponding positive electrode of one of the M second constant current sources or M variable resistors, functioning as a current supply point, at least one collector sense terminal arranged on the outer periphery of the test stage, a first probe, a second probe, and a voltage measuring unit. The aforementioned semiconductor test method is The steps include fixing a wafer on which multiple semiconductor elements are arranged to the test stage and connecting the positive electrodes of the multiple semiconductor elements to the test stage, The steps include: connecting each of the N first probes to a corresponding negative electrode among the N semiconductor elements and a corresponding negative electrode among the N first constant current sources; Each of the N second probes connects to a corresponding control electrode among the N semiconductor elements and to a drive circuit. The N first constant current sources begin supplying a constant current, The steps include: each of the M second constant current sources or each of the M variable resistors starts supplying a current equal to 1 / M of the sum of the currents from the N first constant current sources; A semiconductor testing method comprising the step of the voltage measuring unit measuring the voltage between the collector sense terminal and each of the N negative electrodes of the semiconductor elements.

12. The steps of manufacturing semiconductor devices using a wafer process, The steps include testing the manufactured wafers and The process includes the step of commercializing semiconductor devices that have passed the tests, A method for manufacturing a semiconductor device, wherein the step of testing the wafer is performed using the semiconductor testing method described in claim 11.

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