JP2015038442A - Current supply device and semiconductor device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a current supply device capable of making values of supply currents flowing to respective conductive members as uniform as possible and a semiconductor device manufacturing method using the same.SOLUTION: A current supply device 31 supplies an AC current to an active area 35 of an IGBT 34 via a pin group formed by arranging spring pins 6 serving as a plurality of conductive members. The pin group of the spring pins 6 is configured so that a uniform current can flow to the respective spring pins 6 at a time of supplying an AC current, and so that the spring pin 6 located outward in the pin group is higher or larger in impedance or diameter than the spring pin 6 located inward.

Description

  The present invention relates to a current supply device that includes a conductor member group in which a plurality of conductor members are arranged, supplies an alternating current to an object through the conductor member group, and a semiconductor element manufacturing method using the same.

  Conventionally, as such a current supply device, a device for supplying a current for inspection to a semiconductor element or the like through a contact portion having a large number of pyramidal projections is known (for example, see Patent Document 1). In the device described in Patent Document 1, the contact portion is pressed against the semiconductor element by a spring so that each protrusion comes into contact with the electrode or the like of the semiconductor element, and an inspection current is supplied.

  According to this, since the contact portion is in good contact with the electrode of the semiconductor element by each protrusion, and the inspection current is distributed and applied by each protrusion, it is considered that a large inspection current can be applied.

  On the other hand, the present inventors have proposed a current supply device configured by supporting a flat contact electrode with a probe assembly in which a large number of spring probes are integrated. According to this current supply device, a large current can be supplied by pressing and electrically connecting the contact electrode to the semiconductor device. At this time, the probe assembly allows the contact electrode to contact the semiconductor device following its inclination.

  The probe assembly also functions as an electric circuit for supplying current to the contact electrode. That is, a large current is supplied to the semiconductor device in a state where the semiconductor device, the contact electrode, and the probe integrated body are connected in series.

JP 2007-218675 A

  By the way, in a screening test for power semiconductor elements such as IGBTs (insulated gate bipolar transistors) and power MOSFETs, a large current is applied to a contact region in an active region of the semiconductor element. In this case, in order to supply a large current as uniformly as possible over the entire contact area, the current is evenly distributed and supplied by the above-described protrusion group of Patent Document 1 and the contact electrode supported by the above-described probe assembly. It is preferable to do this.

  In this case, the current resistance value of one protrusion or spring probe (hereinafter referred to as “conductor member”) is the same. Therefore, the number of necessary conductor members can be determined according to the magnitude of the necessary supply current. Further, according to the number of conductor members, the arrangement pitch of the conductor members can be set so as to correspond to the area of the contact region in the active region.

  However, the present inventors have found that the supply current does not flow evenly distributed among the conductor members, but that a larger amount of current tends to flow through the conductor members arranged outside the arrangement of the conductor members. It was done.

  Thus, when the magnitude | size of the electric current which flows into a conductor member arises, the magnitude | size of the supply current as a whole is restrict | limited by the conductor member through which the largest electric current flows. If it does so, there exists a possibility that the electric current of the magnitude | size which is intended cannot be supplied.

  In view of the problems of the prior art, the present invention is to provide a current supply device capable of making the value of the supply current flowing through each conductor member as uniform as possible and a semiconductor element manufacturing method using the current supply device.

  A first invention is a current supply device that includes a conductor member group in which a plurality of conductor members are arranged, and supplies an alternating current to an object through the conductor member group, and each conductor member is supplied when the alternating current is supplied. In the conductor member group, the impedance of the conductor member located on the outside is made larger than the impedance of the conductor member located on the inside so that the current flowing through the conductor becomes uniform.

  In general, when an alternating current is supplied to an object through a conductor member group, the higher the frequency of the alternating current, the higher the degree of current flowing through the surface of the object due to the skin effect. For this reason, in the conductor member located on the outer side of the conductor member group, current tends to flow into the surface of the object around the array, so that there is a tendency that more current flows than the conductor member located inside the conductor member.

  Further, when the arrangement of the conductor members is configured by arranging the same conductor members at equal intervals, the impedance of the conductor members closer to the outer periphery of the arrangement becomes smaller. For this reason, the electric current which flows by the conductor member of the outer side of a conductor member group and the conductor member inside it becomes non-uniform | heterogenous.

  In this regard, in the present invention, the conductor member group is configured such that the conductor member arranged on the outer side has a larger impedance than the conductor member arranged on the inner side. For this reason, the nonuniformity of said electric current can be relieve | moderated and the electric current which flows about the outer side conductor member and an inner side conductor member can be equalized.

  A second invention includes a conductor member group in which a plurality of columnar conductor members are arranged and supplies an alternating current to an object through the conductor member group. In the conductor member group, the cross-sectional area of the conductor member located on the outer side in the conductor member group is larger than the area of the cross-section of the conductor member located on the inside so that the current flowing through the conductor member is uniform. To do.

  In the second invention, a conductor member having a larger cross-sectional area than the inner conductor member is disposed outside the conductor member group. In this case, by appropriately selecting the area of the cross section, the impedance of the outer conductor member can be made larger than the impedance of the inner conductor member. Or compared with the case of the arrangement | sequence of the conductor member with the same cross-sectional area, the impedance of the conductor member of an outer side can be increased to a larger degree than the conductor member of the inner side.

  Therefore, as in the case of the first invention described above, the current non-uniformity can be alleviated, and the flowing current can be made uniform for the outer conductor member and the inner conductor member.

  According to a third aspect of the present invention, there is provided a semiconductor device manufacturing method comprising: a current supply step of supplying a predetermined large current to an active region of a formed semiconductor device by the current supply device of the first or second invention; and the current supply step. A determination step of determining whether or not the semiconductor element is destroyed by the supplied current, and a selection step of selecting, as the manufactured semiconductor element, the semiconductor element determined to be not destroyed by the determination step. Features.

  According to this, in the current supply step, the current flowing through the conductor member group of the current supply device used is uniform, so that a current having an intended magnitude can be easily supplied. Therefore, it is possible to easily manufacture only a semiconductor element that is excellent in breakdown resistance with respect to current and in which safe operation is reliably guaranteed.

It is a perspective view of the electric current supply apparatus which concerns on one Embodiment of this invention. It is a disassembled perspective view of the electric current supply apparatus of FIG. It is a schematic diagram which shows a mode that an electric current is supplied with the electric current supply apparatus which concerns on another embodiment of this invention. With respect to the case where the spring-loaded pins are arranged in 5 rows and 5 columns in the current supply device of FIG. 1 or FIG. 3, (a) shows each spring-loaded pin when the radius of all the spring-loaded pins is 0.25 [mm]. The impedance [Ω] of the pin is shown, and (b) shows the current value flowing through each spring-loaded pin when the inspection current is supplied in this case, and the current value of the spring-loaded pin in the middle 3 rows and columns c. (C) shows the radius of the outermost spring-loaded pin of 0.5 [mm] and the inner radius of the spring-loaded pin 6 is 0.25 [mm]. (D) shows the current shunt ratio in this case, and (e) shows that the radius of the outermost spring-loaded pin is 0.75 [mm]. When the radius of the inner spring pin is 0.25 [mm], Impedance [Ω] is shown, and (f) shows the current shunt ratio in this case. In the case where the spring-loaded pins are arranged in 9 rows and 9 columns in the current supply device of FIG. 1 or FIG. 3, (a) shows the impedance [Ω of each spring-loaded pin when the radii are all 0.25 [mm]. (B) shows the current shunt ratio of each spring-loaded pin in this case, (c) shows the radius of the outermost spring-loaded pin being 0.5 [mm], and the inner spring-loaded pin The impedance [Ω] of each spring-equipped pin when the radius of 0.25 is 0.25 [mm] is shown, and (d) shows the current shunt ratio in this case. In the case where the spring-loaded pins are arranged in 11 rows and 11 columns in the current supply device of FIG. 1 or FIG. 3, (a) shows the impedance [Ω of each spring-loaded pin when the radii are all 0.25 [mm]. (B) shows the current shunt ratio of each spring-loaded pin in this case, (c) shows the radius of the outermost spring-loaded pin being 0.5 [mm], and the inner spring-loaded pin Shows the impedance [Ω] of each spring-loaded pin 6 when the radius of 0.25 is [mm], (d) shows the current shunt ratio in this case, and (e) shows the spring with the outermost circumference. Each of the cases where the radius of the pin is 0.5 [mm], the radius of the inner spring-loaded pin 6 is 0.35 [mm], and the inner radius of the spring-loaded pin is 0.25 [mm] The impedance [Ω] of the pin with spring is shown, and (f) shows the current shunt ratio in this case.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The current supply device of the embodiment is used for applying an inspection current for inspecting a semiconductor element to the semiconductor element, and particularly for inspecting a power semiconductor element used for switching a large current of about 400 to 2000 [A]. Is suitable. Examples of the semiconductor element include an IGBT (Insulated Gate Bipolar Transistor) and a power MOSFET.

  As shown in FIGS. 1 and 2, the current supply device 1 holds a disk-shaped contact portion 2 that contacts a semiconductor element when supplying an inspection current to the semiconductor element to be inspected, And a pressing portion 3 that presses against the semiconductor element.

  The contact portion 2 has a contact surface 4 that comes into contact with the semiconductor element on the side where the semiconductor element to be inspected is arranged (hereinafter, simply referred to as “element side”). The pressing part 3 has a substantially cylindrical shape, and holds the contact part 2 inside thereof. The holding unit 3 holds the contact unit 2 in such a manner that the contact surface 4 is substantially perpendicular to the direction of the cylindrical axis (hereinafter simply referred to as “axial direction”), and the semiconductor along the axial direction. Press against the element.

  As shown in FIG. 2, the pressing portion 3 includes a disk-shaped base portion 5, spring-attached pins 6 as a large number of conductor members arranged vertically and horizontally on the element-side surface of the base portion 5, and springs A disc-shaped guide support portion 7 for guiding the attached pin 6 along the axial direction while supporting the pin 6 in a direction perpendicular to the axial direction, and a ring-shaped mounting portion for attaching the contact portion 2 to the element side of the guide support portion 7 8, an insulating plate 9 that insulates the contact portion 2 and the attachment portion 8, and a cylindrical pin 10 that guides the contact portion 2 in the axial direction.

  The guide support portion 7 is fixed in parallel to the base portion 5 with a fixing screw 11. The base 5 is provided with a positioning hole 12 for inserting and positioning the end of the cylindrical pin 10 opposite to the element side, and a screw hole 13 into which the fixing screw 11 is screwed. A signal pin 21 is erected on the base 5 in parallel with the spring-loaded pins 6 at a position away from the arrangement of the spring-loaded pins 6.

  The guide support portion 7 includes a guide hole group 14 composed of the same number of through-holes as the spring-loaded pins 6 that support the spring-supported pins 6 in the axial direction while supporting the pins 6 with the springs, and the cylindrical pins 10. Are provided in the direction perpendicular to the axial direction while guiding them in the axial direction, and a cylindrical protrusion 16 standing on the element side surface. The protrusion 16 is provided with a through hole for allowing the signal pin 21 to pass therethrough.

  A male screw for fixing the attachment portion 8 to the guide support portion 7 is provided on the outer periphery of the guide support portion 7. The arrangement of the guide hole groups 14 forms a rectangular pattern corresponding to the contact surface 4 of the contact portion 2 on the element-side surface of the guide support portion 7. That is, the surface of the contact portion 2 opposite to the contact surface 4 is supported in a region just corresponding to the contact surface 4 by each spring-equipped pin 6 guided by the guide hole group 14.

  The guide hole 15 and the protrusion 16 are located outside the two opposite sides of the rectangular pattern. The contact portion 2 is provided with through holes 17 and 18 at positions corresponding to the guide holes 15 and the protruding portions 16. The portion constituting the contact surface 4 of the contact portion 2 travels to the element side through a step and forms a rectangular trapezoidal portion.

  The insulating plate 9 is provided with an opening hole 19 into which the protruding portion 16 of the guide support portion 7 is inserted, and an opening 20 into which the base portion constituting the contact surface 4 is inserted. The insulating plate 9 has an outer diameter that fits in the inner wall of the mounting portion 8. On the inner wall of the attachment portion 8, a female screw corresponding to the male screw of the guide support portion 7 is provided. The end surface on the element side of the attachment portion 8 is opened with an inner diameter slightly smaller than the outer diameter of the insulating plate 9.

  The current application device 1 can be assembled as follows. That is, first, the spring-loaded pins 6 are loaded into the guide hole group 14 of the guide support portion 7, the signal pins 21 are passed through the through holes of the protruding portion 16, and the guide support portion 7 is fixed to the base portion with the two fixing screws 11. Attach to 5. Next, the cylindrical pin 10 is inserted into the guide hole 15 of the guide support portion 7, and the end portion of the cylindrical pin 10 is inserted into the positioning hole 12 of the base portion 5.

  Next, the contact portion 2 is disposed on the element side of the guide support portion 7 such that the cylindrical pin 10 and the protruding portion 16 of the guide support portion 7 are inserted into the through holes 17 and 18, respectively. Next, the guide for the insulating plate 9 to be inserted into the opening 20 of the plate-like part constituting the contact surface 4 of the contact part 2 and to protrude into the opening hole 19 from the through hole 18 of the contact part 2. It arrange | positions at the element side of the contact part 2 so that the protrusion part 16 of the support part 7 may be inserted.

  Then, the attachment portion 8 is fixed to the guide support portion 7 by fastening the female screw of the attachment portion 8 to the male screw of the guide support portion 7. Thereby, the assembly of the electric current application apparatus 1 is completed, and the contact part 2 and the pressing part 3 will be in the state of FIG.

  In this state, the tip of the signal pin 21 protrudes from the tip of the protrusion 16. In addition, a region corresponding to the contact surface 4 on the surface opposite to the contact surface 4 of the contact portion 2 is supported on the base portion 5 while being biased toward the element side by a large number of spring-loaded pins 6. The contact portion 2 is positioned in a direction perpendicular to the axial direction by the cylindrical pin 10 and the protruding portion 16 and is guided so as to be somewhat movable in the axial direction.

  For this reason, when the contact portion 2 is pressed against the active region of the semiconductor element to be inspected, if there is a difference in inclination between the active region and the contact surface 4, the contact portion 2 is somewhat Can tilt.

  At the time of applying the inspection current to the semiconductor element, the current supply device 1 is positioned at a predetermined position with respect to the semiconductor element by the semiconductor inspection device in which the current supply device 1 is incorporated. At this position, the pressing portion 3 presses the contact portion 2 against the semiconductor element by the arrangement of the spring-loaded pins 6 so that the contact surface 4 contacts a predetermined contact area on the semiconductor element.

  At this time, since the contact portion 2 is guided by the cylindrical pin 10 and the protruding portion 16 so as to be slightly tiltable, the slight inclination of the contact surface 4 with respect to the contact region of the semiconductor element is a contraction amount of each spring-loaded pin 6. Absorbed by difference. As a result, the contact surface 4 comes into contact with the contact region of the semiconductor element with a substantially uniform pressing force. In this state, when an inspection current is supplied to the contact portion 2 via the cylindrical pin 10, the inspection current is supplied to the contact area of the semiconductor element via the contact surface 4.

  FIG. 3 shows a state in which an inspection current is supplied by a current supply device according to another embodiment. As shown in FIG. 3, in the current supply device 31, when supplying the inspection current to the semiconductor element to be inspected, the contact portion 32 that contacts the semiconductor element via the rectangular contact surface 32a and the contact portion 32 are provided. And a pressing part 33 that holds and presses the semiconductor element.

  As in the case of the current supply device 1 described above, the pressing portion 33 holds the contact portion 32 while urging the contact portion 32 toward the element side by a large number of spring-loaded pins 6. The spring-loaded pin 6 is configured by connecting a spring 6a and a pin 6b in series. The pressing portion 33 is provided with a signal pin 21 as in the case of the current supply device 1.

  As shown in FIG. 3, when inspecting the IGBT 34, the current supply device 31 is pressed against the IGBT 34 so that the contact portion 32 is in contact with the active region 35 of the IGBT 34 and the signal pin 21 is in contact with the gate 36. . In addition, a high-frequency inspection current is supplied to each pin 6 with a spring via a common electrode 37. A gate signal is supplied to the signal pin 21 through a signal electrode 39 insulated from the common electrode 37 by the insulating member 38.

  At this time, if there is a difference in inclination between the active region 35 and the contact surface 32a, the spring-loaded pin 6 contracts and the contact portion 32 is inclined so that the difference is eliminated. The inspection current is supplied to the active area 35 via the arrangement of the spring-loaded pins 6 and the contact portion 32. The inspection current is supplied to the IGBT 34 in the same manner in the case of the current supply device 1 of FIG.

  When a high-frequency inspection current is supplied by the current supply device 1 or the current supply device 31 in this way, the current tends to flow on the surface of the metal due to the skin effect. That is, the supply current flows exclusively on the surface of the contact portion 2 or the contact portion 32.

  A conductor surface that is not in contact with the spring-loaded pins 6 spreads outside the external spring-loaded pins 6 in the arrangement of the spring-loaded pins 6. For this reason, the spring-loaded pins 6 on the outer side of the array are more likely to flow current than the inner pins.

  Accordingly, if the spring-loaded pins 6 have the same specifications and are arranged at the same interval, the current concentrates on the spring-loaded pins 6 on the outer side of the arrangement. In addition, when the spring-loaded pins 6 having the same specifications are arranged at the same interval, the external spring-loaded pin 6 has a smaller impedance than the inner one. It becomes a factor which current concentrates.

  When the current concentrates on the external spring-loaded pin 6, the current-proof value of each spring-loaded pin 6 is the same, so even if the overall supply current value is small, the current-proof value of the external spring-loaded pin 6 is The current that reaches For this reason, there is a possibility that current supply with an intended current value cannot be performed.

  Therefore, in the current supply device 1 and the current supply device 31, the impedance of the external spring-loaded pin 6 is made larger than that of the inner one. Specifically, this is achieved by making the diameter of the external spring-loaded pin 6 larger than the inner one.

  As a result, the current flows more easily through the inner spring-loaded pin 6 than through the outer spring-loaded pin 6. Therefore, the tendency of current concentration on the outer spring-loaded pin 6 due to the skin effect described above can be alleviated, and the current value passing through the spring-loaded pin 6 can be averaged for the outer side and the inner spring-loaded pin 6 as a whole. it can.

  FIG. 4 shows the effect obtained by making the diameter of the external spring-loaded pin 6 larger than that of the internal pin. The spring-loaded pin 6 is divided into 5 rows 1 to 5 and 5 columns a to e. Fig. 6 shows the case where the elements are arranged at equal intervals.

  FIG. 4A shows the impedance [Ω] of each spring-loaded pin 6 when the radius of all the spring-loaded pins 6 is 0.25 [mm]. In FIG. 4B, in this case, the current value flowing through each spring-loaded pin 6 when the inspection current is supplied is the current value (hatched portion) of the 3 × c spring-loaded pin 6 located in the center. The value is 1.00 (hereinafter referred to as “current shunt ratio”).

  The impedance Z of one spring-loaded pin 6 is expressed by the following equation.

  Here, R is the resistance of the pin 6 with spring, ω is the angular frequency of the alternating current flowing through the pin 6 with spring, and L is the inductance of the pin 6 with spring. The inductance L is expressed by the following equation.

  Here, Ls is a self-inductance of the pin 6 with spring, and M is a mutual inductance. The self inductance Ls is expressed by the following equation.

Here, μ is the relative magnetic permeability, μ ₀ is the vacuum magnetic permeability, b is the length of the spring-loaded pin 6, and a is the radius of the spring-loaded pin 6. The mutual inductance M _nm between the n-th spring-loaded pin 6 and the m-th spring-loaded pin 6 is expressed by the following equation.

Here, Ls _n is the self-inductance of the n-th spring-loaded pin 6, and Ls _m is the self-inductance of the m-th spring-loaded pin 6. The mutual inductance M of the spring-loaded pin 6 is the sum of the mutual inductances with the other spring-loaded pins 6.

  When the radii of the spring-loaded pins 6 are all 0.25 [mm] as shown in FIGS. 4A and 4B, the impedance of the outer spring-loaded pins 6 depends on the other spring-loaded pins 6. Since the contribution to the mutual inductance is small, it is smaller than the impedance of the inner spring pin 6. Accordingly, the current shunt ratio of the outer spring-loaded pin 6 is larger than the current shunt ratio of the inner spring-loaded pin 6.

  In FIG. 4C, the radius of the outermost spring-loaded pin 6 corresponding to the hatched portion is 0.5 [mm], and the radius of the inner spring-loaded pin 6 is 0.25 [mm]. The impedance [Ω] of each spring-loaded pin 6 is shown. FIG. 4D shows the current shunt ratio in this case.

  Also in this case, the impedance of the outermost spring-loaded pin 6 is smaller than the impedance of the inner spring-loaded pin 6. However, as compared with the case of FIG. 4B, the current shunt ratio is close to the center 1.00 because the value of the outermost spring-loaded pin 6 becomes smaller. Accordingly, when the radius of the outermost spring-loaded pin 6 is increased, as shown in FIG. 4 (d), the value of the current flowing through each spring-loaded pin 6 is uniform compared to the case of FIG. 4 (b). You can see that

  In FIG. 4E, the radius of the outermost spring-loaded pin 6 corresponding to the hatched portion is 0.75 [mm], and the radius of the inner spring-loaded pin 6 is 0.25 [mm]. The impedance [Ω] of each spring-loaded pin 6 is shown. FIG. 4F shows the current shunt ratio in this case.

  Even in this case, the impedance of the outermost spring-loaded pin 6 is smaller than the impedance of the inner spring-loaded pin 6. However, the current shunt ratio in FIG. 4 (f) is smaller than that in FIG. 4 (b), and the value of the outermost spring-loaded pin 6 is smaller and approaches the center of 1.00. Therefore, it can be seen that even when the radius of the outer spring pin 6 is set to 0.75 [mm], the value of the current flowing through each spring pin 6 can be made uniform as compared with the case of FIG.

  FIG. 5 shows the effect of making the diameter of the external spring-loaded pins 6 larger than that of the inner ones. The spring-loaded pins 6 are arranged in 9 rows 1 to 9 and 9 columns a to i at equal intervals. It shows about the case where it arranged by. FIG. 5A shows the impedance [Ω] of each pin 6 with a spring when the radii are all 0.25 [mm]. FIG. 5B shows the current shunt ratio of each spring-loaded pin 6 when the current value of the spring-loaded pin 6 in the center 5 rows and e columns is 1.00.

  Also in this case, as in the case of FIGS. 4A and 4B described above, the impedance of the external spring-loaded pin 6 is smaller than the impedance of the inner spring-loaded pin 6. Accordingly, the current shunt ratio of the outer spring-loaded pin 6 is larger than the current shunt ratio of the inner spring-loaded pin 6.

  In FIG. 5C, the radius of the outermost spring-loaded pin 6 corresponding to the hatched portion is 0.5 [mm], and the radius of the inner spring-loaded pin 6 is 0.25 [mm]. The impedance [Ω] of each spring-loaded pin 6 is shown. FIG. 5D shows the current shunt ratio in this case. In this case, except for the spring-loaded pins 6 at the four corners, the impedance of the outermost spring-loaded pin 6 is larger than the impedance of the inner spring-loaded pin 6.

  Correspondingly, the current shunt ratio is also smaller than the innermost spring-loaded pin 6 except for the spring-loaded pins 6 at the four corners, which is smaller than that in the case of FIG. The value is close to 1.00 at the center. Therefore, when the radius of the outermost spring-loaded pin 6 is set to 0.5 [mm], the value of the current flowing through each spring-loaded pin 6 becomes uniform compared to the case of FIG.

  FIG. 6 shows an effect obtained by making the diameter of the external spring-loaded pin 6 larger than that of the inner one. The spring-loaded pins 6 are arranged in 11 rows 1 to 11 and 11 columns a to k at equal intervals. It shows about the case where it arranged by. FIG. 6A shows the impedance [Ω] of each pin 6 with a spring when the radii are all 0.25 [mm]. FIG. 6B shows the current shunt ratio of each spring-loaded pin 6 when the current value of the spring-loaded pin 6 in the middle 6 rows and f columns is 1.00.

  Also in this case, the impedance of the external spring-loaded pin 6 is smaller than the impedance of the inner spring-loaded pin 6. Accordingly, the current value of the spring-loaded pin 6 on the outer side is larger than the current value of the inner spring-loaded pin 6.

  In FIG. 6C, the radius of the outermost spring-loaded pin 6 corresponding to the hatched portion is 0.5 [mm], and the radius of the inner spring-loaded pin 6 is 0.25 [mm]. The impedance [Ω] of each spring-loaded pin 6 is shown. FIG. 6D shows the current shunt ratio in this case.

  In this case, the impedance of the outermost spring-loaded pin 6 is larger than the impedance of the inner spring-loaded pin 6. Accordingly, the current shunt ratio is also smaller for the outermost spring-loaded pin 6 than for the inner spring-loaded pin 6 and closer to the central value of 1.00 than in the case of FIG. 6B. It has become. That is, when the radius of the outermost spring-loaded pin 6 is 0.5 [mm], the current flowing through each spring-loaded pin 6 becomes uniform compared to the case of FIG.

  In FIG. 6E, the radius of the outermost spring-loaded pin 6 corresponding to the hatched portion is 0.5 [mm], and the radius of the inner spring-loaded pin 6 is 0.35 [mm]. mm], and the impedance [Ω] of each spring-loaded pin 6 when the radius of the spring-loaded pin 6 inside is 0.25 [mm] is shown. FIG. 6F shows the current shunt ratio in this case.

  In this case, the impedance of the inner spring pin 6 on the innermost outermost circumference is larger than the impedance of the inner spring pin 6. Further, the impedance of the pin 6 with the outermost spring is larger than the impedance of the pin 6 with the spring inside the outermost one.

  Correspondingly, the current shunt ratio of the innermost spring-loaded pin 6 is smaller than the current shunt ratio of the inner spring-loaded pin 6. The value is close to 00. Further, the current shunt ratio of the outermost spring-loaded pin 6 is smaller than the current shunt ratio of the innermost spring-loaded pin 6 and is 1.00 in the center than in the case of FIG. It is close.

  Therefore, even if the radius of the outermost spring-loaded pin 6 is 0.5 [mm] and the radius of the inner spring-loaded pin 6 is 0.35 [mm], each spring-loaded pin 6 flows. The current becomes uniform as compared with the case of FIG.

  As described above, according to the present embodiment, the one arranged on the outside side in the arrangement of the spring-loaded pins 6 has a larger impedance or diameter than the one arranged on the inside thereof. The flowing current can be made uniform over the entire array of spring pins 6.

  The current supply device 1 and the current supply device 31 of the above-described embodiment manufacture a semiconductor element that sufficiently satisfies the design value of a reverse biased safe operation area (RBSOA) when manufacturing a semiconductor element such as an IGBT. Can be used to

  The reverse bias safe operation region represents the non-destructive operation range of the collector-emitter voltage and the collector current accompanying the turn-off of the IGBT in the voltage-current region. The wider the reverse bias safe operating area, the higher the non-destructive performance against reverse bias. The process for manufacturing only the semiconductor element that sufficiently satisfies the design value of the reverse bias safe operation region includes the following current supply process, determination process, and selection process.

  In the current supply process, the inspection current is supplied to the active region of the formed semiconductor element using the current supply device 1 or 31 as described above. For example, an IGBT formed on a semiconductor substrate corresponds to the semiconductor element.

  The supplied current has, for example, a current value that is twice the design value for the maximum current in the reverse bias safe operation region. This is to ensure the safe operation of the manufactured semiconductor element. Specifically, if the design value is 500 amperes, a current of 1000 amperes, twice that amount, is supplied. In this current supply step, the current supply device 1 or the current supply device 31 is used, so that a current having an intended magnitude can be easily supplied.

  In the determination step, it is determined whether or not the semiconductor element is destroyed by the current supplied in the current supply step. For example, in the case of IGBT, the presence or absence of breakdown is determined by examining the leakage current between the gate and the emitter and the leakage current between the collector and the emitter.

  In the sorting step, the semiconductor elements determined to have been destroyed in the determination step are removed, and only the semiconductor elements determined to have not been destroyed are selected as manufactured (products). As a result, it is possible to manufacture only semiconductor elements that are guaranteed safe operation.

  In addition, this invention is not limited to said embodiment. For example, the arrangement interval of the spring-loaded pins 6 may not be constant. The shape of the array is not limited to a rectangular shape, and may be a circular shape or the like. Even in this case, when the current concentrates on the spring-loaded pins 6 on the external side of the array, the current flowing in each spring-supported pin 6 is increased by increasing the diameter of the external spring-loaded pins 6 to increase the impedance. Can be made as uniform as possible.

  Moreover, in the said embodiment, although the diameter of the pin 6 with a spring was enlarged in order to enlarge the impedance of the pin 6 with a spring, it replaces with this and changes the magnetic permeability and length of the pin 6 with a spring. You may enlarge the impedance of the pin 6 with a spring.

  Moreover, in the said embodiment, although the contact part 2 is supported by the pin 6 with a spring, and the electric current is supplied to the active area | region 35 of IGBT34 via the contact part 2, it replaces with this and the pin 6 with a spring is directly attached. A current may be supplied in contact with the active region 35.

  DESCRIPTION OF SYMBOLS 1, 31 ... Current supply apparatus, 6 ... Pin with spring (conductor member), 34 ... IGBT (target object).

Claims (3)

A current supply device comprising a conductor member group formed by arranging a plurality of conductor members, and supplying an alternating current to an object through the conductor member group,
In the conductor member group, the impedance of the conductor member located on the outside is made larger than the impedance of the conductor member located on the inside so that the current flowing through each conductor member becomes uniform when the alternating current is supplied. A current supply device. A current supply device comprising a conductor member group formed by arranging a plurality of columnar conductor members, and supplying an alternating current to an object through the conductor member group,
In order to make the current flowing through each conductor member uniform when supplying the alternating current, the area of the cross section of the conductor member located on the outside in the conductor member group is larger than the area of the cross section of the conductor member located on the inside. A current supply device characterized by the fact that it is also enlarged. A current supply step of supplying a predetermined large current to the active region of the formed semiconductor element by the current supply device according to claim 1,
A determination step of determining whether or not the semiconductor element is destroyed by the current supplied in the current supply step;
A semiconductor element manufacturing method, comprising: a selecting step of selecting, as a manufactured semiconductor element, a semiconductor element determined not to be destroyed by the determining step.