Semiconductor testing device, semiconductor testing method, and method for producing semiconductor device

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

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

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

[0002] The product performance of semiconductor devices is guaranteed by conducting characteristic tests during the manufacturing process, which include tests such as applying high voltages or large currents to the semiconductor devices, and screening.

[0003] Characteristic tests include tests performed on modules and tests performed on semiconductor elements. To reduce manufacturing costs, it is preferable to perform characteristic tests on wafers. However, there is a problem of low reproducibility of measurement results due to the electrical resistance that changes depending on the contact between the test stage on which the wafer is placed and the backside of the wafer, and the difference in resistance of the path from the test stage to the measurement point.

[0004] Japanese Patent Application Laid-Open No. 2003-144222 discloses a method for testing semiconductor transistors, which reduces the contact resistance between a test stage and the back surface of a wafer.

[0005] In Patent Document 1, the density of the suction holes provided on the test stage is set to 100 holes / cm 2 By doing so, the contact resistance between the test stage and the wafer backside electrode can be reduced, thereby alleviating the problem of low measurement reproducibility.

[0006] JP 2015-26765 A

[0007] However, the test method described in Patent Document 1 cannot eliminate the effect of differences in resistance along the path to the measurement point on the test stage, which causes measurement errors to vary across the wafer. Furthermore, the test method described in Patent Document 1 cannot measure multiple chips simultaneously.

[0008] Therefore, an object of the present disclosure is to provide a semiconductor testing device, a semiconductor testing method, and a method for manufacturing a semiconductor device that can measure multiple chips simultaneously in tests performed on semiconductor elements in wafer form and reduce the variation in measurement error within the wafer surface.

[0009] The semiconductor testing device disclosed herein is a semiconductor testing device for simultaneously testing the characteristics of N (N is a natural number of 2 or more) semiconductor elements that have a positive electrode on the back surface and a negative electrode and a control electrode on the front surface and that turn on or off in response to a control signal input to the control electrode, and includes a test stage that fixes a wafer on which a plurality of semiconductor elements are arranged and serves as a positive electrode that is 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) third constant current sources, each having a negative electrode connected to the positive electrodes of the N first constant current sources. The test stage includes two constant current sources or M variable resistors, N first probes each connecting a negative electrode of a corresponding one of the N semiconductor elements to a negative electrode of a corresponding one of the N first constant current sources, M electrodes each arranged on the periphery of the test stage and connected to a positive electrode of a corresponding one of the M second constant current sources or the M variable resistors and functioning as a current supply point, at least one collector sense terminal arranged on the periphery of the test stage, and a voltage measurement unit for measuring a voltage between the collector sense terminal and each of the negative electrodes of the N semiconductor elements. Each of the M second constant current sources or each of the M variable resistors passes a current that is 1 / M of the sum of the currents of the N first constant current sources.

[0010] The semiconductor testing method disclosed herein is a semiconductor testing method using a semiconductor testing apparatus for simultaneously testing the characteristics of N (N is a natural number of 2 or greater) semiconductor elements, each of which has a positive electrode on its back surface and a negative electrode and a control electrode on its front surface, and which turns on or off in response to a control signal input to the control electrode. The semiconductor testing apparatus includes a test stage serving as a positive electrode, N (N is a natural number of 2 or greater) first constant current sources, M (M is a natural number of 2 or greater) second constant current sources or M variable resistors, each of which has a negative electrode connected to the positive electrode of the N first constant current sources, M electrodes arranged on the periphery of the test stage, each of which is connected to the positive electrode of a corresponding 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 arranged on the periphery of the test stage, a first probe, a second probe, and a voltage measurement unit. The semiconductor testing method includes 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, using N first probes, a negative electrode of a corresponding one of the N semiconductor elements to a negative electrode of a corresponding one of the N first constant current sources; connecting, using N second probes, a control electrode of a corresponding one of the N semiconductor elements to a drive circuit; starting the supply of constant currents from the N first constant current sources; starting the supply of currents that are 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, using a voltage measurement unit, a 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 the present disclosure includes the steps of fabricating semiconductor elements by a wafer process, testing the fabricated wafers, and commercializing semiconductor elements that pass the test. The step of testing the wafers uses the semiconductor testing method described above.

[0012] According to the present disclosure, in tests performed on semiconductor devices in a wafer state, multiple chips can be measured simultaneously, and the variation in measurement error within the wafer surface can be reduced.

[0013] FIG. 10 is a diagram showing the configuration of a semiconductor testing apparatus according to a first embodiment. FIG. 11 is a diagram showing a simplified path related to saturation voltage measurement of a semiconductor element 27 according to the first embodiment. FIG. 12 is a diagram showing a simplified path related to saturation voltage measurement of a semiconductor element 26 according to the first embodiment. FIG. 13 is a flowchart showing the procedure for saturation voltage testing of a semiconductor element according to the first embodiment. FIG. 14 is a diagram showing the configuration of a semiconductor testing apparatus according to a second embodiment. FIG. 15 is a diagram showing the configuration of a semiconductor testing apparatus according to a third embodiment. FIG. 16 is a flowchart showing the procedure for saturation voltage testing of a semiconductor element according to the third embodiment. FIG. 17 is a diagram showing the configuration of a semiconductor testing apparatus according to a fourth embodiment. FIG. 18 is a diagram showing a simplified path related to saturation voltage measurement of a semiconductor element 27 according to the fourth embodiment. FIG. 19 is a diagram showing a simplified path related to saturation voltage measurement of a semiconductor element 26 according to the fourth embodiment. FIG. 19 is a flowchart showing the measurement procedure for saturation voltage measurement according to the fourth embodiment. FIG. 19 is a diagram showing the configuration of a semiconductor testing apparatus according to a fifth embodiment. FIG. 19 is a diagram showing the configuration of a semiconductor testing apparatus according to a sixth embodiment. FIG. 19 is a flowchart showing the measurement procedure for saturation voltage measurement according to the sixth embodiment. FIG. 19 is a flowchart showing a method for manufacturing a semiconductor device according to a seventh embodiment.

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

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

[0016] Referring to FIG. 1, a case where eight semiconductor elements arranged on a wafer are simultaneously tested will be described. Eight semiconductor elements 26a-26h or eight semiconductor elements 27a-27h are simultaneously tested. The number of elements that can be simultaneously tested is not limited to this. FIG. 1 shows only four of the semiconductor elements 26a-26h and 27a-27h. This semiconductor testing apparatus includes a test stage 51, first probes 53a-53h, second probes 54a-54h, a drive circuit 55, first constant current sources 1a-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 first probes 53a to 53h is the same as the number of semiconductor devices to be simultaneously measured, which is eight. Only two probes are shown in Figure 1. The number of second probes 54a to 54h is the same as the number of semiconductor devices to be simultaneously measured, which is eight. Only one probe is shown in Figure 1.

[0018] The test stage 51 fixes a wafer 63. A plurality of semiconductor elements are arranged on the wafer 63. Any self-arc-extinguishing semiconductor elements can be used as the semiconductor elements. All of the semiconductor elements arranged on the wafer 63, or a portion of all of the semiconductor elements, are sampled and inspected. The semiconductor elements 27a-h and the semiconductor elements 26a-h are representative of the plurality of semiconductor elements arranged on the wafer 63.

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

[0020] The semiconductor elements 26 and 27 have a positive electrode on their back surfaces and a negative electrode and control electrode on their front surfaces. 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 refers to the drain electrode, the negative electrode refers to the source electrode, and the control electrode refers to the gate electrode. If the semiconductor elements 26 and 27 are IGBTs (Insulated Gate Transistors), the positive electrode refers to the collector electrode, the negative electrode refers to the emitter electrode, and the control electrode refers to the gate electrode. The following description will be given using the case where the semiconductor elements 26 and 27 are IGBTs as an example.

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

[0022] The positive electrodes (collectors in the case of IGBTs) on the rear surfaces of the semiconductor elements 26 and 27 are directly electrically connected to a test stage 51 (conductor) which also serves as the positive electrode.

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

[0024] The first electrode 31 is arranged 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 2 a. The first electrode 31 functions as a first current supply point to the test stage 51. The second electrode 32 is arranged 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 2 b. 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] The on-resistance (equivalent resistance) of semiconductor element 27a in the saturation voltage test is indicated by resistor 17a, and the on-resistance (equivalent resistance) of semiconductor element 26a is indicated by resistor 16a. First electrode 31 and second electrode 32 are arranged on the outer periphery of test stage 51. It is desirable that first electrode 31 and second electrode 32 be arranged at equal angular intervals on the outer periphery of test stage 51 (i.e., at positions point-symmetrical with respect to the center of test stage 51).

[0026] The first probe 53a electrically connects the positive electrode of the second constant current source 2a 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.

[0027] The first probe 53a electrically connects the positive electrode of the second constant current source 2a 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.

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

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

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

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

[0032] The first probe 53a electrically connects the positive electrode of the second constant current source 2b 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.

[0033] The first probe 53a connects the positive electrode of the second constant current source 2b 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.

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

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

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

[0037] Strictly speaking, the resistor 13 is different between the 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 described as resistor 13, but it is also possible to have resistors 13a to 13h corresponding to the semiconductor elements 27a to 27h. The same applies to resistors 12, 14, and 15.

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

[0039] The collectors of the semiconductor elements are electrically connected to wafer 63 by contacting the backside of the semiconductor elements with wafer 63. The front side of the semiconductor elements has gate electrodes and emitter electrodes (not shown). Semiconductor elements 27a-h have emitter electrodes 127a-h, and semiconductor elements 26a-h have emitter electrodes 126a-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 arranged on the outer periphery of the test stage 51. The collector sense terminal 33 is arranged closer to the first electrode 31 than to the second electrode 32. It is more preferable that the collector sense terminal 33 be arranged in the vicinity of the first electrode 31. The collector sense terminal 33 is electrically connected to the positive electrodes on the back surfaces 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-h. The voltage measurement unit 3 preferably includes eight voltmeters in parallel so that eight voltages can be measured simultaneously. Alternatively, the voltage measurement unit 3 may be configured to measure the voltages between the collector sense terminal 33 and the emitter electrodes 127a-h of eight semiconductor elements by switching a switch. The latter configuration allows the cost of the semiconductor testing equipment to be reduced.

[0043] The saturation voltage of the semiconductor element 27 can be measured by four terminals using the second constant current source 2 and the voltage measurement unit 3. Since only a minute current flows between the collector sense terminal 33 and the first electrode 31 and the electrical resistance between the two 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 brought into electrical contact with any semiconductor element on the wafer 63 .

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

[0046] When measuring the saturation voltage of the semiconductor element 27a, the drive circuit 55 applies a voltage to the control electrode of the semiconductor element 27a through the second probe 54a, thereby turning on the semiconductor element 27a. 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 with the voltage measuring unit 3.

[0047] When measuring the saturation voltage of the semiconductor element 26a, the drive circuit 55 applies a voltage to the control electrode of the semiconductor element 26a through the second probe 54a, thereby turning on the semiconductor element 26. 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 with the voltage measuring unit 3.

[0048] It is preferable that the first electrode 31 and the second electrode 32 are positioned point-symmetrically with respect to the center of the test stage 51. Assuming that the resistance of the test stage 51 is uniform, and ignoring the contact resistance between the positive electrode on the back surface of the semiconductor element and the test stage 51, the magnitudes of the resistors 12, 13, 14, and 15 are proportional to the distance from the electrodes to the semiconductor element. If the first electrode 31 and the second electrode 32 are positioned point-symmetrically with respect to the center of the test stage 51, and the semiconductor elements 26 and 27 are positioned point-symmetrically with respect to the center of the test stage 51, the value of resistor 13 will be the same as the value of resistor 15, and the value of resistor 14 will be the same as the value of resistor 12, and therefore the saturation voltage of the semiconductor element 26 will be the same as the saturation voltage of the semiconductor element 27. However, even if the electrodes are not positioned point-symmetrically, the variation in the saturation voltage measurement error within the wafer 63 due to semiconductor testing equipment such as resistor 13 can be reduced.

[0049] Fig. 2 is a simplified diagram of a path related to the measurement of the saturation voltage of the semiconductor element 27 in the first embodiment. Fig. 3 is a simplified diagram of a path related to the measurement of the saturation voltage of the semiconductor element 26 in the first embodiment.

[0050] A method for calculating the measured value of saturation voltage (also called Vce(sat)), which is a typical large current test, will be described with reference to FIGS. 2 and 3. Since calculations using variables are complicated, real numbers are substituted for resistance values ​​here. In the following description, the semiconductor elements 26 and 27 under test will be described as IGBTs.

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

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

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

[0054] In a typical conventional saturation voltage test, there is one second constant current source 2 and one or two current supply points. When there is one current supply point, the farther the semiconductor device is located from the current supply point, the greater the resistance of the test stage 51, resulting in a higher measured saturation voltage than the true value. Therefore, when there is one current supply point, the measurement error of the semiconductor device's saturation voltage varies across the wafer 63. When there are two current supply points, current is supplied from a single constant current source through two separate current paths. Therefore, if the sum of the wiring resistance and the resistance of the test stage is not equal for the two current paths, the current will be unbalanced. However, because the resistance of the test stage varies depending on the position of the semiconductor device, it is difficult to equalize the resistance of the two current paths.

[0055] In this embodiment, second constant current sources 2 a and 2 b can cause a constant current of, for example, 200 A, which is half of the desired current (400 A in this case), to flow through first electrode 31, thereby reducing the measurement error due to resistor 13 by half. As a result, it is possible to reduce the variation within wafer 63 of the measurement error in the saturation voltage of the semiconductor element caused by the current.

[0056] For the resistance values ​​shown in FIG. 2, when the current flowing through the collectors of semiconductor elements 27a-27b is 400 A, a current of 50 A, one-eighth of that current, flows through semiconductor element 27a. The saturation voltage of semiconductor element 27a is 0.45 V. For the resistance values ​​shown in FIG. 3, the saturation voltage of semiconductor element 26a is 0.55 V. In FIGS. 2 and 3, when there is one constant current source, a current of 400 A flows through resistors 12 and 13, so the saturation voltage of semiconductor element 27a is 0.55 V and the saturation voltage of semiconductor element 26a is 0.75 V. In this embodiment, second constant current sources 2a and 2b reduce measurement errors and narrow the difference in the saturation voltages of semiconductor elements 27a and 26a, i.e., improve the in-plane distribution.

[0057] FIG. 4 is a flowchart showing the procedure of a saturation voltage test for a semiconductor device according to the first embodiment.

[0058] In step S02, the semiconductor testing equipment is connected to a plurality of semiconductor elements under test. For example, if the semiconductor elements under test are semiconductor elements 27a-h, the emitters on the front surfaces of the semiconductor elements 27a-h are electrically connected to the negative electrodes of the first constant current sources 1a-h by needle-shaped first probes 53a-h. The gates on the front surfaces of the semiconductor elements 27a-h are electrically connected to a drive circuit 55 of the semiconductor testing equipment by needle-shaped second probes 54a-h. The collectors on the back surfaces of the semiconductor elements 27a-h are directly and electrically connected to a test stage 51 (conductor) that serves as the positive electrode.

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

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

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

[0062] In step S05, if the measured saturation voltage is within the specification, the process proceeds to step S06, whereas if the measured saturation voltage is out of the specification, the process proceeds to step S07.

[0063] In step S06, the semiconductor elements 27a-h under test are judged as pass. In step S07, the semiconductor elements 27a-h under test are judged as fail. If they fail, for example, the semiconductor elements under test may be marked with ink. Pass or fail may also 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 testing equipment is stopped. That is, the output of current from the first constant current sources 1a-h and the second constant current sources 2a-b is stopped. The driving circuit 55 turns off the semiconductor elements 27a-h under test.

[0065] In step S09, the semiconductor testing equipment is disconnected from the semiconductor elements 27a to 27h under test.

[0066] In step S10, the test stage 51 moves to the measurement position for the next semiconductor element. The processes of steps S01 to S10 are repeated until all the 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, the current flowing through the first electrode 31 and the second electrode 32 is the same, and therefore it is possible to reduce the variation in measurement error across the surface of the wafer 63 in a large current test such as measuring the saturation voltage of a semiconductor element.

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

[0069] The resistance component of the path from resistor 17 to the negative electrode of first constant current source 1 causes the saturation voltage of semiconductor element 27 to deviate from its true value, and the only way to reduce this deviation is to reduce the resistance component. In the first embodiment, by providing two constant current sources and two current supply points, the current flowing through first electrode 31 is reduced by half. This reduces the voltage drop caused by 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 equal to or greater than 3. The M electrodes are arranged at equal angular intervals on the outer periphery of the test stage 51. Each of the M electrodes is connected to a corresponding one of the M second constant current sources and functions as one of the M current supply points.

[0071] 5 is a diagram showing the configuration of a semiconductor testing apparatus according to a second embodiment. FIG. 5 shows the case where M=4. In addition to the configuration of the semiconductor testing apparatus according to the first embodiment, this semiconductor testing apparatus further includes a second constant current source 2c, a second constant current source 2d, a third electrode 131, and a fourth electrode 132. A resistor 110 is the resistance of the electrical wiring between the second constant current source 2c and the third electrode 131. A resistor 111 is the resistance of the electrical wiring between the second constant current source 2d and the fourth electrode 132. Resistance components within the test stage 51 are not shown in the figure.

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

[0073] According to this embodiment, the current flowing through the first electrode 31 is reduced to 1 / M, and therefore the voltage drop due to the resistor 13 is reduced to 1 / M. Therefore, the deviation of the saturation voltage from the true value caused by 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] 6 is a diagram showing the configuration of a semiconductor test apparatus according to embodiment 3. The semiconductor test apparatus according to embodiment 3 differs from the semiconductor test apparatus according to embodiment 1 in that the semiconductor test apparatus according to embodiment 3 includes only a first constant current source 1, a first variable resistor 71, a second variable resistor 72, a first ammeter 81, and a second ammeter 82.

[0075] A first end of the first variable resistor 71 is connected to the positive electrode of the first constant current source 1a to 1h, and a second end of the first variable resistor 71 is connected to the first electrode 31. A first end of the second variable resistor 72 is connected to the positive electrode of the first constant current source 1a to 1h, and a second end 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] FIG. 7 is a flowchart showing the procedure of a saturation voltage test for a semiconductor device according to the third embodiment.

[0078] The flowchart of the third embodiment differs from the flowchart of the second embodiment in that the flowchart of the third embodiment includes step S04a instead of step S04.

[0079] In step S04a, the supply of current from the semiconductor testing equipment 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 readings of the first ammeter 81 and the second ammeter 82 are equal. The first variable resistor 71 starts supplying a current that is 1 / 2 the sum of the currents of the first constant current sources 1a to 1h. The second variable resistor 72 starts supplying a current that is 1 / 2 the sum of the currents of 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 and the current flowing through the second electrode 32 equal, it is possible to reduce the variation in measurement error within the surface of the wafer 63 in large current tests such as saturation voltage measurements.

[0081] Modification 1 of Embodiment 3. In this modification, 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 distribution of voltage drop is created on a wafer, such as a TEG (Test Element Group) wafer, in which the resistance values ​​of the semiconductor elements are known. Since the current value and the resistance value of the semiconductor element are known, it is possible to determine 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.

[0082] Modification 2 of Embodiment 3. By making the first variable resistor 71 and the second variable resistor 72 equal in size and setting the resistance values ​​of the first variable resistor 71 and the second variable resistor 72 sufficiently larger than the resistance components of the current path on the test stage, such as the wiring resistor 10, and the contact resistance between the semiconductor element and the test stage, it is possible to achieve half the equal current. 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 magnitude of the first variable resistor 71 and the magnitude of the second variable resistor 72 so that the current flowing through the first electrode 31 and the second electrode 32 is always equal, the same effect as in embodiment 3 can be obtained.

[0084] Variation 3 of Embodiment 3. As in Embodiment 2, there may be M variable resistors and M current supply points. M is a natural number greater than or equal to 3. The M electrodes are arranged at equal angular intervals on the outer periphery of the test stage 51. Each of the M electrodes is connected to a corresponding one of the M variable resistors and functions as M current supply points. An ammeter may be used to measure the current flowing through each of the M variable resistors 71, and the resistance value of each of the M variable resistors 71 may be adjusted so that each of the M variable resistors 71 supplies a current that is 1 / M of the sum of the currents of the first constant current sources 1a to 1h.

[0085] 8 is a diagram showing the configuration of a semiconductor test apparatus according to a fourth embodiment. The semiconductor test apparatus according to the fourth embodiment differs from the semiconductor test apparatus according to the first embodiment in that the semiconductor test apparatus according to the fourth embodiment includes a collector sense terminal 34, and includes a voltage measurement unit 3a and an arithmetic unit 69 instead of the voltage measurement unit 3.

[0086] The collector sense terminal 34 is disposed at a position closer to the second electrode 32 than to the first electrode 31. It is more preferable that the collector sense terminal 34 be disposed near the second electrode 32. The collector sense terminal 34 is electrically connected to the positive electrodes on the back surfaces of the semiconductor elements 26 and 27.

[0087] The voltage measurement unit 3a measures the voltages Vce(sat)Aa-h between the collector sense terminal 33 and the emitter electrodes 127a-h. At the same time, the voltage measurement unit 3a measures the voltages 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 calculation device 69 calculates the measured voltages Vce(sat)Aa-h and Vce(sat)Ba-h to determine the saturation voltage Vce(sat) of the semiconductor element. For example, the calculation device 69 can calculate the average value of Vce(sat)Aa-h and Vce(sat)Ba-h as the saturation voltage Vce(sat)a-h of the semiconductor element.

[0089] Fig. 9 is a simplified diagram of a path related to the measurement of the saturation voltage of the semiconductor element 27 in the fourth embodiment. Fig. 10 is a simplified diagram of a path related to the measurement of the saturation voltage of the semiconductor element 26 in the fourth embodiment.

[0090] 9 and 10, a method for calculating the measured values ​​of saturation voltage, a common high-current test, will be described. Because calculations using variables are complicated, real numbers will be substituted for the resistance values. That is, resistor 10 is 0.1 Ω, resistor 11 is 0.11 Ω, resistor 12 is 0.001 Ω, resistor 13 is 0.0005 Ω, resistor 14 is 0.001 Ω, resistor 15 is 0.0005 Ω, resistors 16a-h are 0.007 Ω, and resistors 17a-h are 0.007 Ω. These are the same resistance values ​​as those in FIGS. 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. When the positional relationship between the semiconductor element 27 and the first electrode 31 and the positional relationship between the semiconductor element 26 and the second electrode 32 are point-symmetric with respect to the center point of the test stage 51, as in the case of the semiconductor element 26 and the semiconductor element 27, the magnitude of the resistor 13 and the magnitude of the resistor 14 will be the same.

[0092] In an actual test device, the resistance component of the test stage 51 is not uniform, and the electrical contact resistance between the positive electrode on the back surface of the wafer 63 and the test stage 51 is not uniform. Therefore, the magnitudes of the resistors 13 and 14 will differ depending on the position of the semiconductor element on the wafer 63. In this embodiment, the two measured values ​​Vce(sat)Aa-h and Vce(sat)Ba-h can be averaged, for example, to reduce the variation in the magnitudes of the resistors 13 and 14.

[0093] The calculation device 69 may change the method for determining the saturation voltages Vce(sat)a to Vce(sat)h of the semiconductor element from the measured values ​​Vce(sat)Aa to Vce(sat)Ah and Vce(sat)Ba to Vce(sat)h depending on the position of the semiconductor element.

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

[0095] Alternatively, when 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 measurement values ​​Vce(sat)Aa-h are considered to be less affected by path resistance than the measurement values ​​Vce(sat)Ba-h and closer to the true value, and therefore the calculation device 69 may use the measurement values ​​Vce(sat)Aa-h as the saturation voltages Vce(sat)a-h of the semiconductor elements 27a-h.

[0096] 11 is a flowchart showing the procedure for measuring the saturation voltage according to the fourth embodiment. The flowchart according to the fourth embodiment differs from the flowchart according to the first embodiment in that the flowchart according to the fourth embodiment includes step S041a instead of step S041.

[0097] In step S041a, the voltage measurement unit 3a measures the voltages Vce(sat)Aa-h between the collector sense terminal 33 and the emitter electrodes 127a-h. The voltage measurement unit 3a measures the voltages Vce(sat)Ba-h between the collector sense terminal 34 and the emitter electrodes 127a-h. For example, the calculation device 69 can calculate (e.g., average) these measured values ​​to determine the saturation voltages Vce(sat)a-h of the semiconductor elements 27a-h under test.

[0098] As described above, according to the semiconductor testing apparatus and semiconductor testing method of the fourth embodiment, the current flowing through the first electrode 31 and the second electrode 32 is constant, and the saturation voltage is determined by calculating the measured values ​​at two points, thereby making it possible to reduce the variation in measurement error within the surface of the wafer 63 in a high current test.

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

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

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

[0102] The M electrodes are arranged at equal angular intervals on the periphery of the test stage 51. Each of the M electrodes is connected to a corresponding one of the M second constant current sources 2 and functions as M current supply points. Each of the M collector sense terminals is arranged at a position closer to a corresponding one of the M electrodes than to any of the other M electrodes.

[0103] FIG. 12 is a diagram showing the configuration of a semiconductor testing apparatus according to a fifth embodiment. FIG. 12 shows the case where M=4. In addition to the configuration of the semiconductor testing apparatus according to the fourth embodiment, this semiconductor testing 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. A resistor 110 is the resistance of the electrical wiring between the second constant current source 2c and the third electrode 131. A resistor 111 is the resistance of the electrical wiring between the second constant current source 2d and the fourth electrode 132. The resistance components within the test stage 51 are not shown in the figure.

[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 at 90° intervals on the outer periphery of the test stage 51.

[0105] The collector sense terminal 33 is disposed at a position closer to the electrode 31 than to the electrodes 32, 131, and 132. The collector sense terminal 133 is disposed at a position closer to the electrode 131 than to the electrodes 31, 32, and 132. The collector sense terminal 34 is disposed at a position closer to the electrode 32 than to the electrodes 31, 131, and 132. The collector sense terminal 134 is disposed at a position closer to the electrode 132 than to the 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 the resistor 13 is reduced to 1 / M. Therefore, the deviation of the saturation voltage from its true value caused by the resistor 13 can be reduced to 1 / M.

[0107] Sixth Embodiment Fig. 13 is a diagram showing the configuration of a semiconductor testing device according to a sixth embodiment.

[0108] The semiconductor testing device of the sixth embodiment differs from the semiconductor testing device of the fifth embodiment in the positions of the collector sense terminals 33, 34, 133, and 134.

[0109] The collector sense terminal 33 is arranged on the outer periphery of the test stage 51 at a position equidistant from the positions of the electrodes 31 and 132. The collector sense terminal 134 is arranged on the outer periphery of the test stage 51 at a position equidistant from the positions of the electrodes 132 and 32. The collector sense terminal 34 is arranged on the outer periphery of the test stage 51 at a position equidistant from the positions of the electrodes 32 and 131. The collector sense terminal 133 is arranged on the outer periphery of the test stage 51 at a position equidistant from the positions of the electrodes 131 and 31.

[0110] In the fifth embodiment, the electrode 31 and the collector sense terminal 33 are considered to have the same potential, but by separating the current flow point and the voltage measurement point, they are no longer at the same potential.

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

[0112] For example, let's consider the case where semiconductor elements 27a-h are measured. Because collector sense terminal 33 is located close to semiconductor elements 27a-d and is not affected by electrodes 31, 32, 132, and 133 through which current flows, the calculation device 69 can use the measurement result of the voltage Vce between collector sense terminal 33 and emitter electrodes 127a-h. The measurement value of the voltage Vce between other collector sense terminals, such as collector sense terminal 134 and emitter electrodes 127a-h, overlaps with the current flowing from electrode 132 toward semiconductor elements 27a-d, resulting in a large voltage drop. The same applies to other collector sense terminals. The calculation device 69 stores wafer map information. Using this map information, the calculation device 69 uses one of the measurements of the voltage Vce between collector sense terminals 33, 334, 133, and 134 and emitter electrodes 127a-h, depending on the position of the semiconductor element. The arithmetic unit 69 can 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.

[0113] Alternatively, the arithmetic unit 69 can determine the smallest measurement value of the voltage Vce between the collector sense terminals 33, 334, 133, 134 and the emitter electrodes 127a-h as the saturation voltage Vce(sat)a-h of the semiconductor elements 27a-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, etc.

[0114] 14 is a flowchart showing the procedure for measuring the saturation voltage according to the sixth embodiment. The flowchart according to the sixth embodiment differs from the flowchart according to the first embodiment in that the flowchart according to the sixth embodiment includes step S041b instead of step S041.

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

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

[0117] Seventh Embodiment In the seventh embodiment, a method for manufacturing a semiconductor device including the semiconductor elements 26 and 27 in the above-described first to sixth embodiments will be described. In other words, the seventh embodiment will describe a method for manufacturing a semiconductor device that includes the semiconductor testing method according to the first to sixth embodiments in the manufacturing process.

[0118] 15 is a flow chart showing a method for manufacturing a semiconductor device according to the seventh embodiment. In step S101, a semiconductor element is fabricated by a wafer process.

[0119] In step S102, the manufactured wafer is tested. In this test, the semiconductor device test method shown in the first to sixth embodiments is carried out. Furthermore, a dynamic characteristic test may be added.

[0120] In step S103, semiconductor elements that have passed the test are commercialized by dicing the wafer into individual semiconductor elements if they are to be shipped in wafer form, or by mounting the semiconductor elements in modules if they are to be shipped as semiconductor elements.

[0121] In the present disclosure, the embodiments can be combined, modified, or omitted as appropriate within the scope of the invention.

[0122] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0123] 1a to h first constant current source, 2a to d second constant current source, 3, 3a voltage measurement unit, 10, 11, 12, 13, 13a, 14, 15, 16a, 17, 17a, 110, 111 resistor, 26a to h, 27a to h semiconductor element, 31, 32, 131, 132 electrode, 33, 34, 133, 134 collector sense terminal, 51 test stage, 53a to h first probe, 54a to h second probe, 55 drive circuit, 63 wafer, 69 arithmetic unit, 71, 72 variable resistor, 81, 82 ammeter, 126a to h, 127a to h emitter electrode.

Claims

1. A semiconductor test device having a positive electrode on the inner surface, a negative electrode and a control electrode on the outer surface, and simultaneously testing the characteristics of N (N is a natural number of 2 or more) semiconductor elements that turn on or off according to a control signal input to the control electrode, comprising: A test stage that fixes a wafer on which a plurality of the semiconductor elements are arranged and has the role of a positive electrode that is 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, Each having 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 N first constant current sources, N first probes each connecting a corresponding one of the negative electrodes of the N semiconductor elements and a corresponding one of the negative electrodes of the N first constant current sources, M electrodes each arranged on the outer periphery of the test stage, connected to a corresponding one of the positive electrodes of the M second constant current sources or the M variable resistors, and functioning as a current supply point, At least one collector sense terminal arranged on the outer periphery of the test stage, And a voltage measurement unit that measures the voltage between the collector sense terminal and each of the negative electrodes of the N semiconductor elements. The semiconductor test device is such that each of the M second constant current sources or each of the M variable resistors conducts a current that is 1 / M of the sum of the currents of the N first constant current sources.

2. The semiconductor test device according to claim 1, further comprising N second probes each connecting a corresponding one of the control electrodes of the N semiconductor elements and a drive circuit.

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

4. The semiconductor test device according to claim 1 or 2, wherein the M electrodes are configured to be movable on the outer periphery.

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

6. ​ The semiconductor test apparatus according to claim 5, further comprising an arithmetic unit that averages the M voltages measured for each of the M collector sense terminals for each of the N semiconductor elements by the voltage measurement unit.

7. Each comprising M ammeters for measuring the currents flowing through the M variable resistors, The semiconductor test 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 at least one collector sense terminal includes M collector sense terminals, Each of the M collector sense terminals is disposed at a position equidistant from the positions of two adjacent electrodes among the M electrodes, The semiconductor test apparatus according to any one of claims 1 to 3, wherein the voltage measurement unit measures the voltage between each of the M collector sense terminals and each of the negative electrodes of the N semiconductor elements.

9. The semiconductor test apparatus according to claim 8, further comprising an arithmetic unit that calculates, for each of the N semiconductor elements, the minimum value among the M voltages measured for the M collector sense terminals as the saturation voltage of the semiconductor element.

10. The semiconductor test apparatus according to claim 8, further comprising an arithmetic unit that calculates, for each of the N semiconductor elements, the voltage measured for the collector sense terminal closest to the semiconductor element as the saturation voltage of the semiconductor element among the M voltages measured for the M collector sense terminals.

11. A semiconductor test method by a semiconductor test apparatus for simultaneously testing the characteristics of N (N is a natural number of 2 or more) semiconductor elements that have a positive electrode on the back surface, a negative electrode and a control electrode on the front surface, and turn on or off according to a control signal input to the control electrode. The semiconductor test apparatus includes a test stage having a role of a positive electrode, 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) second constant current sources each having a negative electrode connected to the positive electrodes of the N first constant current sources, or M variable resistors, M electrodes each disposed on the outer periphery of the test stage and connected to a corresponding one of the positive electrodes of the M second constant current sources or the M variable resistors and functioning as current supply points, at least one collector sense terminal disposed on the outer periphery of the test stage, a first probe, a second probe, and a voltage measurement unit. The semiconductor test method is as follows. Fixing a wafer on which a plurality of the semiconductor elements are arranged to the test stage and connecting the positive electrodes of the plurality of semiconductor elements to the test stage. Connecting each of the N first probes to a corresponding one of the negative electrodes of the N semiconductor elements and a corresponding one of the negative electrodes of the N first constant current sources. Connecting each of the N second probes to a corresponding one of the control electrodes of the N semiconductor elements and a drive circuit. The N first constant current sources start supplying a constant current. Each of the M second constant current sources or each of the M variable resistors starts supplying a current that is 1 / M of the sum of the currents of the N first constant current sources. The voltage measurement unit measures the voltage between the collector sense terminal and each of the negative electrodes of the N semiconductor elements. A semiconductor test method comprising the steps.

12. Manufacturing semiconductor elements by a wafer process. Testing the manufactured wafer. Commercializing the semiconductor elements that have passed the test. A manufacturing method of a semiconductor device comprising the steps. The step of testing the wafer uses the semiconductor test method described in Claim 11.