JP2013105776A - Semiconductor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of further reducing workload on manufacturing a semiconductor module than before.SOLUTION: A semiconductor module 2 is manufactured by installing a first bus bar 50, a second bus bar 80, and a vertical semiconductor element 70 on predetermined positions of a wrapping sheet 10 and then wrapping the wrapping sheet 10 around a member to be wrapped. When the wrapping sheet 10 is wrapped around a cooler 40, one surface of the semiconductor element 70 and the first bus bar 50 are electrically connected, and the other surface of the semiconductor element 70 and the second bus bar 80 are electrically connected. For this reason, when the semiconductor module 2 is manufactured, there is no need to accurately align each component of the semiconductor element 70, the first bus bar 50, the second bus bar 80 and to stack them.

Description

  The present invention relates to a semiconductor module having a semiconductor element and a bus bar electrically connected to the semiconductor element.

  In Patent Document 1, a drain electrode of a vertical semiconductor chip is joined to a bus bar by soldering, and is electrically connected to another bus bar via an elastic conductor soldered to the source electrode of the semiconductor chip. A semiconductor module is disclosed.

JP 2007-31523 A

  When manufacturing the semiconductor module of Patent Document 1, it is necessary to accurately position and stack a semiconductor chip, a bus bar, and an elastic conductor, and solder them. Therefore, when manufacturing the conventional semiconductor module, the burden of the alignment work of each element is large.

  In the present specification, a technique capable of reducing the work burden when manufacturing a semiconductor module as compared with the prior art is disclosed.

  The semiconductor module disclosed in the present specification includes a winding sheet, a member to be wound around which the winding sheet is wound, a first bus bar installed in a first bus bar installation part of the winding sheet, and a second bus bar installation part of the winding sheet. A second bus bar to be installed and a vertical semiconductor element to be installed in the element installation part of the wound sheet are provided. When the winding sheet is wound around the member to be wound, one surface of the semiconductor element installed in the element installation unit and the first bus bar installed in the first bus bar installation unit are electrically connected and installed in the element installation unit The other surface of the formed semiconductor element and the second bus bar installed in the second bus bar installation part are electrically connected. The winding sheet communicates the front and back surfaces of the winding sheet and has a communication hole that electrically connects one surface of the semiconductor element and the first bus bar or the other surface of the semiconductor element and the second bus bar. ing.

  In the semiconductor module, the first bus bar is installed in the first bus bar installation section, the second bus bar is installed in the second bus bar installation section, the vertical semiconductor element is installed in the element installation section, and the winding sheet is covered. It is manufactured by winding around a winding member. That is, when the winding sheet is wound around the member to be wound, one surface of the semiconductor element and the first bus bar are electrically connected, and the other surface of the semiconductor element and the second bus bar are electrically connected. Therefore, when manufacturing the above-described semiconductor module, it is not necessary to stack the semiconductor element, the first bus bar, and the second bus bar by accurately aligning each other. Compared to a conventional method in which each element needs to be accurately aligned and stacked, the work load when forming a semiconductor module can be reduced. Also, when the winding sheet is wound around the member to be wound, the winding sheet may be located between the bus bar and the semiconductor element. In that case, by forming a communication hole in the winding sheet, the bus bar and the semiconductor element Can be electrically connected. As a result, the semiconductor element and each bus bar can be electrically connected.

  In one aspect of the semiconductor module described above, the first bus bar installation portion and the second bus bar installation portion are provided on one surface of the winding sheet, while the element installation portion is provided on the other surface of the winding sheet. Also good. The element installation part may be provided at a position facing the first bus bar installation part when the winding sheet is wound around the member to be wound. The second bus bar installation part may be provided on the back side of the element installation part. The communication hole may be provided at a position where the second bus bar installation part and the element installation part communicate with each other. As a result, the other surface of the semiconductor element installed in the element installation section and the second bus bar installed in the second bus bar may be electrically connectable through the communication hole.

  The wound member is preferably a cooler. According to this structure, a semiconductor element is arrange | positioned on the surface of a cooler by winding a winding sheet around the to-be-wrapped member which is a cooler. Therefore, the semiconductor element can be effectively cooled.

It is a top view which shows the structure of the semiconductor module of 1st Example, and has shown the state before winding the winding sheet | seat 10 around the cooler 40. FIG. It is a bottom view which shows the structure of the semiconductor module of 1st Example, and has shown the state before winding the winding sheet | seat 10 around the cooler 40. FIG. It is a figure which shows the cross section along the III-III line of the semiconductor module of 1st Example, and has shown the state after winding the winding sheet | seat 10 around the cooler 40. FIG. The front view which shows a 1st bus bar. The top view which shows a semiconductor element. The front view which shows a spring board. Sectional drawing which shows a mode that a winding sheet is wound around a cooler. Sectional drawing which shows the semiconductor module of 2nd Example. Sectional drawing which shows the semiconductor module of 3rd Example. The top view which shows the semiconductor module of 4th Example. The top view which shows the semiconductor module of 5th Example. The top view which shows the semiconductor module of 6th Example. Sectional drawing which shows the semiconductor module of 7th Example. Sectional drawing which shows the semiconductor module of 8th Example. Sectional drawing which shows the semiconductor module of 9th Example. The top view which shows the other example of the semiconductor module of 9th Example. Sectional drawing which shows the semiconductor module of 9th Example which shows another example. Sectional drawing which shows the semiconductor module of 10th Example. Sectional drawing which shows the semiconductor module of 11th Example.

(First embodiment)
As shown in FIGS. 1 to 3, the semiconductor module 2 of this embodiment includes a winding sheet 10, a cooler 40, a first bus bar 50, four signal lines 60, a semiconductor element 70, and a second element. A bus bar 80, a spring plate 90, and a pressing plate 98 are provided. In the present embodiment, by winding the winding sheet 10 around the cooler 40, the first bus bar 50 and the surface electrode 74 (see FIG. 5) of the semiconductor element 70 are electrically connected, and the signal line 60 and the semiconductor element 70 are connected. The signal pad 76 (see FIG. 5) is electrically connected, the second bus bar 80 and the back electrode (not shown) of the semiconductor element 70 are electrically connected, and the semiconductor module 2 is completed.

  As shown in FIGS. 1 and 2, the winding sheet 10 has a band-shaped main body 12. The main body 12 includes a first bus bar installation unit 14, a signal line installation unit 16, a second bus bar installation unit 18, an element installation unit 22, a spring plate installation unit 24, and a pressing plate installation unit 28.

  The main body 12 is a resin-made sheet-like member having insulating properties, and is formed in a band shape. The main body 12 can be formed of polyimide, for example.

  The 1st bus-bar installation part 14 hold | maintains the 1st bus-bar 50 installed, as shown in FIG. The first bus bar installation part 14 includes two corner holding parts 14 a formed on the surface of the main body 12 and a bus bar insertion part 14 b. In the present embodiment, the first bus bar 50 is inserted into the bus bar insertion portion 14b, and the two corner portions at the tip of the first bus bar 50 are respectively held by the corner holding portions 14a, whereby the first bus bar 50 is moved to the first bus bar. Install in the installation unit 14.

  As shown in FIG. 1, the signal line installation unit 16 holds the four signal lines 60 that are installed. The signal line installation part 16 is formed on the surface of the main body 12 at a position adjacent to the first bus bar installation part 14. The signal line installation part 16 includes four cylindrical parts through which the signal line 60 can be inserted. In the present embodiment, the four signal lines 60 are installed in the signal line installation unit 16 by inserting the tips of the four signal lines 60 into the cylindrical portion of the signal line installation unit 16. The tip of the signal line 60 installed in the signal line installation unit 16 extends in the direction of the first bus bar 50.

  The 2nd bus-bar installation part 18 hold | maintains the 2nd bus-bar 80 installed, as shown in FIG. The second bus bar installation part 18 is provided on the surface of the main body 12 at a position spaced apart from the first bus bar installation part 14 and the signal line installation part 16 in the longitudinal direction of the wound sheet 10. . The structure of the 1st bus-bar installation part 18 is substantially the same as said 1st bus-bar installation part 14, and is provided with the two corner holding parts 18a and the bus-bar insertion part 18b.

  The element installation unit 22 holds the semiconductor element 70 to be installed as shown in FIG. The element installation unit 22 is provided on the back surface of the main body 12 and on the back side of the second bus bar installation unit 18. Moreover, the position of the element installation part 22 is a position facing the first bus bar installation part 14 when the winding sheet 10 is wound around the cooler 40 (see FIG. 3). As shown in FIG. 2, the element installation portion 22 includes corner holding portions 22 a that can hold the four corner portions of the semiconductor element 70 at four locations. In the present embodiment, the four corner portions of the semiconductor element 70 are held by the corner holding portions 22a, respectively, so that the semiconductor element 70 is set in the element setting portion 22.

  As shown in FIG. 1, the second bus bar installation unit 18 and the element installation unit 22 communicate with the second bus bar installation unit 18 provided on the front surface of the main body 12 and the element installation unit 22 provided on the back surface of the main body 12. A communication hole 20 is provided. In the present embodiment, as shown in FIG. 3, a conductive layer 82 (described later) having conductivity is disposed in the communication hole 20. Therefore, the second bus bar 80 installed in the second bus bar installation unit 18 and the back electrode of the semiconductor element 70 installed in the element installation unit 22 are electrically connected via the conductive layer 82.

  As shown in FIG. 1, the spring plate installation unit 24 holds a spring plate 90 to be installed. The spring plate installation part 24 is provided on the surface of the main body 12 at a position spaced apart from the second bus bar installation part 18 in the longitudinal direction of the wound sheet 10. The position of the spring plate installing portion 24 is a position facing the second bus bar installing portion 18 when the winding sheet 10 is wound around the cooler 40 (see FIG. 3). As shown in FIG. 1, the spring plate installation portion 24 includes four corner holding portions 24 a that can hold the four corner portions of the spring plate 90. Further, as shown in FIG. 2, a through hole 26 is provided in the main body 12 at a position where the spring plate installation portion 24 is formed. The protrusion 92 of the spring plate 90 can be fitted into the through hole 26. In the present embodiment, the four corner portions of the spring plate 90 are respectively held by the corner holding portions 24a, and the convex portions 92 of the spring plates 90 are fitted into the through holes 26, and the tips of the convex portions 92 are connected to the main body 12. The spring plate 90 is installed in the spring plate installation section 24 by projecting to the back side (see FIG. 3).

  As shown in FIG. 2, the presser plate installation unit 28 holds a presser plate 98 to be installed. The presser plate installation portion 28 is provided on the rear surface of the main body 12 at a position spaced apart from the through hole 26 in the longitudinal direction of the wound sheet 10. The position of the pressing plate installation portion 28 is a position facing the spring plate installation portion 24 when the winding sheet 10 is wound around the cooler 40 (see FIG. 3). As shown in FIG. 2, the pressing plate installation portion 28 includes four corner holding portions 28 a that can hold the four corner portions of the pressing plate 98. In the present embodiment, the presser plate 98 is installed on the presser plate installation unit 28 by holding the four corners of the presser plate 98 on the corner holding unit 24a.

  As shown in FIG. 3, the cooler 40 is a rectangular cylindrical member capable of flowing water therein. The cooler 40 can be formed of Cu, for example.

  As shown in FIG. 1, the first bus bar 50 is a plate-like conductive member. The first bus bar 50 can be formed of, for example, a material obtained by plating Cu or Ni with Au. In the present embodiment, as shown in FIG. 4, a conductive layer 52 having conductivity is provided on the surface of the first bus bar 50 near the tip. For the conductive layer 52, a soft plastic material (for example, Sn) is used.

  As shown in FIG. 1, the signal line 60 is a linear conductive member. The signal line can be formed of Cu, for example. In this embodiment, four signal lines 60 are provided. A pressure contact portion (not shown) is formed at the distal end portion of the signal line 60.

  The semiconductor element 70 is a switching element for electric power, and a vertical MOSFET (Metal Oxide Semiconductor Field Effect Transistor) is used in this embodiment. The semiconductor element 70 can be formed of SiC or the like, for example. As shown in FIG. 5, the semiconductor element 70 is formed to have a substantially rectangular shape in plan view.

  A surface electrode 74 and four signal pads 76 are formed on the front surface side of the semiconductor element 70. The surface electrode 74 and the signal pad 76 are made of a conductive material such as Al. Further, a back surface electrode (not shown) is formed on the back surface side of the semiconductor element 70. The back electrode is formed of a conductive material composed of a plurality of metal layers such as Ni / Ti / Ni / Au.

  The surface electrode 74 is formed above the cell region (region where the MOSFET is formed) of the semiconductor element 70. On the other hand, the back electrode is formed on the entire back surface of the semiconductor element 70. The signal pad 76 is formed above the non-cell region (region where the MOSFET is not formed) of the semiconductor element 70. The signal pad 76 is used to input a gate signal (small current signal) output from an external drive circuit, or to output a detection signal from a temperature detection element (not shown) formed in the semiconductor element 70. It is done. An insulating layer 77 is formed around the surface electrode 74 and the signal pad 76 on the surface of the semiconductor element 70. The surface electrode 74 and the signal pad 76 are insulated by the insulating layer 77.

  The second bus bar 80 is a plate-like conductive member similar to the first bus bar 50 described above. In the present embodiment, as shown in FIG. 1, a conductive layer 82 having conductivity is provided on the back surface of the second bus bar 80. A soft plastic material (for example, Sn) is used for the conductive layer 82.

  As shown in FIG. 6, the spring plate 90 includes a plate-shaped main body 91 and a convex portion 92 formed by projecting the central portion of the main body 91 to one surface side. Both side portions of the convex portion 92 are open. The spring plate 90 can be formed of Cu, SUS (stainless steel), or the like.

  The pressing plate 98 is a plate-like member as shown in FIG. The pressing plate 98 can also be formed of Cu, SUS (stainless steel), or the like.

  A method of manufacturing the semiconductor module 2 of FIG. 3 using each of the above elements will be described. First, the winding sheet 10 is prepared. Next, the first bus bar 50 is installed in the first bus bar installation unit 14, and the four signal lines 60 are installed in the signal line installation unit 16. Next, the second bus bar 80 is installed in the second bus bar installation unit 18. At this time, the conductive layer 82 provided on the back surface of the second bus bar 80 is disposed in the communication hole 20. The surface of the conductive layer 82 protrudes from the communication hole 20 to the back side of the main body 12. Further, the semiconductor element 70 is installed in the element installation unit 22. At this time, the semiconductor element 70 is disposed in the element installation portion 22 so that the back surface side (back electrode side) of the semiconductor element 70 is in contact with the back surface of the main body 12. When the semiconductor element 70 is installed in the element installation unit 22, the back electrode (not shown) of the semiconductor element 70 comes into contact with the conductive layer 82 that protrudes from the communication hole 20 to the back side of the main body 12. As will be described later, when the winding sheet 10 is wound around the cooler 40, the conductive layer 82 is pressed against the back electrode of the semiconductor element 70 by the winding pressure and is plastically deformed. Thereby, the back electrode of the semiconductor element 70 installed in the element installation unit 22 and the second bus bar 80 installed in the second bus bar installation unit 18 are electrically connected via the conductive layer 82. Become. Next, the spring plate 90 is installed in the spring plate installation unit 24. At this time, the convex portion 92 of the spring plate 90 is fitted into the through hole 26. The tip of the convex portion 92 protrudes from the through hole 26 to the back side of the main body 12. Next, the presser plate 98 is installed in the presser plate installation unit 28. Thereby, as shown in FIGS. 1 and 2, each element of the first bus bar 50, the signal line 60, the semiconductor element 70, the second bus bar 80, the spring plate 90, and the pressing plate 98 is held by the winding sheet 10. .

  Next, the winding sheet 10 is wound around the cooler 40 which is a member to be wound. Specifically, first, as shown in FIG. 7, the end of the wound sheet 10 on the side where the first bus bar 50 is installed is fixed to the surface of the cooler 40. Next, the winding sheet 10 is wound around the cooler 40 while pulling the other end side of the winding sheet 10 and applying a pulling force in the direction of the arrow in FIG. The winding of the winding sheet 10 is not limited to the method of winding all the parts as described above, and may be performed by a method of winding each part little by little while installing each part.

  When the winding sheet 10 is wound around the cooler 40, first, the back side of the winding sheet 10 contacts the surface of the cooler 40 as shown in FIG. 3. At this time, the first bus bar 50 installed in the first bus bar installation unit 14 and the four signal lines 60 installed in the signal line installation unit 16 are arranged above the upper surface of the cooler 40.

  When the winding sheet 10 is further wound, the surface electrode 74 of the semiconductor element 70 installed in the element installation unit 22 and the first bus bar 50 face each other. At this time, the surface electrode 74 is in contact with the conductive layer 52 provided on the surface of the first bus bar 50. When the winding sheet 10 is wound, a tensile force is applied to the winding sheet 10. Thereby, the surface electrode 74 is pressed against the conductive layer 52, and the conductive layer 52 is plastically deformed. Accordingly, the surface electrode 74 of the semiconductor element 70 and the first bus bar 50 are electrically connected via the conductive layer 52. At the same time, the signal pad 76 of the semiconductor element 70 is pressed against the pressure contact portions at the tips of the four signal lines 60 installed in the signal line installation portion 16, and the pressure contact portions are plastically deformed. As a result, the four signal pads 76 of the semiconductor element 70 are electrically connected to the corresponding signal lines 60, respectively.

  When the winding sheet 10 is further wound, the surface of the second bus bar installed in the second bus bar installation part 18 and the convex part 92 of the spring plate 90 protruding from the through hole 26 to the back side of the winding sheet 10 face each other. . When the tensile force applied to the winding sheet 10 acts, the convex portion 92 of the spring plate 90 is pressed against the surface of the second bus bar 80.

  When the winding sheet 10 is further wound, the pressing plate 98 installed in the pressing plate installation unit 28 and the surface of the spring plate 90 installed in the spring plate installation unit 24 face each other. The holding plate 98 is pressed against the surface of the spring plate 90 by the pulling force applied to the winding sheet 10. As a result, the surface of the spring plate 90 is pressed by the pressing plate 98. Thus, the second bus bar 80, the semiconductor element 70, the first bus bar 50, and the signal line 60 are pressed against each other by the elastic force of the spring plate 90. As a result, the surface electrode 74 of the semiconductor element 70 and the first bus bar 50 are reliably electrically connected. Similarly, the signal pad 76 and the signal line 60 of the semiconductor element, and the back electrode of the semiconductor element 70 and the second bus bar 80 are reliably electrically connected.

  In this state, the other end of the winding sheet 10 is fixed to complete the semiconductor module 2 shown in FIG. The fixing means of the other end part of the winding sheet | seat 10 is arbitrary. In the semiconductor module 2, the first bus bar 50 and the surface electrode 74 of the semiconductor element 70 are electrically connected, the signal line 60 and the signal pad 76 of the semiconductor element 70 are electrically connected, and the second bus bar 80 and the semiconductor element 70 are electrically connected. The back electrodes are electrically connected. The cooler 40 can cool the first bus bar 50 disposed above the cooler 40, thereby cooling the semiconductor element 70 disposed above the first bus bar 50.

  The configuration of the semiconductor module 2 of the first embodiment and the manufacturing method thereof have been described above. As described above, in this embodiment, by winding the winding sheet 10 around the cooler 40, the surface electrode 74 of the semiconductor element 70 and the first bus bar 50 are electrically connected, and the signal pad 76 of the semiconductor element 70 The signal line 60 is electrically connected, and the back electrode of the semiconductor element 70 and the second bus bar 80 are electrically connected. Therefore, when the semiconductor module 2 is manufactured, it is not necessary to stack the elements of the semiconductor element 70, the first bus bar 50, the signal line 60, and the second bus bar 80 with accurate alignment with each other. Compared with a conventional method in which each element needs to be accurately aligned, stacked, and joined, the work load when manufacturing the semiconductor module 2 can be reduced.

  Further, in the semiconductor module 2 of the present embodiment, the elements of the semiconductor element 70, the first bus bar 50, the signal line 60, and the second bus bar 80 are electrically connected by being brought into pressure contact with each other. That is, it is not necessary to electrically connect the elements of the semiconductor element 70, the first bus bar 50, the signal line 60, and the second bus bar 80 by soldering. Therefore, the work burden when manufacturing the semiconductor module 2 can be further reduced. Also, since no solder is used, the solder is damaged due to the difference in linear expansion between the semiconductor element operating at high temperature and the bus bar, as in the conventional semiconductor module, and as a result, the cooling performance of the semiconductor element deteriorates and the semiconductor The inconvenience that the element is damaged does not occur.

  Further, in the semiconductor module 2 of the present embodiment, the second bus bar installation part 18 is provided on the back side of the element installation part 22, and the back electrode of the semiconductor element 70 and the second bus bar 80 are electrically connected through the communication hole 20. Has been. Therefore, the number of windings of the winding sheet 10 around the cooler 40 when manufacturing the semiconductor module 2 can be reduced as compared with the seventh and eighth embodiments described later.

  Moreover, in the semiconductor module 2 of the present embodiment, the first bus bar 50 and the second bus bar 80 can be made to face each other in parallel. Therefore, when a current flows through the semiconductor element 70, the current can flow in the opposite direction to the first bus bar 50 and the second bus bar 80 facing each other, and as a result, the parasitic inductance can be reduced.

  Moreover, in the semiconductor module 2 of a present Example, since the winding sheet | seat 10 has insulation, between members can be insulated without using an insulating board.

(Second embodiment)
The semiconductor module 102 of the second embodiment will be described focusing on differences from the first embodiment. As shown in FIG. 8, the second embodiment is different from the first embodiment in that the semiconductor elements 170a to 170d are arranged on the surface side of each of the four outer peripheral surfaces of the rectangular tubular cooler 40. Different. Although not shown in FIG. 8, each element such as the first bus bar, the signal line, and the second bus bar is also provided on each of the four outer peripheral surfaces of the rectangular tubular cooler 40. Therefore, in the second embodiment, a semiconductor module having four semiconductor elements 170a to 170d can be manufactured by using all of the four outer peripheral surfaces of the rectangular tubular cooler 40.

(Third embodiment)
In the semiconductor module 202 of the third embodiment, as shown in FIG. 9, the cooler 240 has an octagonal cylindrical shape, and on the surface side of each of the eight outer peripheral surfaces of the octagonal cylindrical cooler 240, Semiconductor elements 270a-h are arranged. Although not shown in FIG. 9, each element such as the first bus bar, the signal line, and the second bus bar is also provided on each of the eight outer peripheral surfaces of the octagonal cylindrical cooler 240. Therefore, in the third embodiment, a semiconductor module having eight semiconductor elements 270a to 270h can be manufactured by using all eight outer peripheral surfaces of the octagonal cylindrical cooler 240.

(Fourth embodiment)
In the semiconductor module 302 of the fourth embodiment, as shown in FIG. 10, two winding sheets 310 a and 310 b are wound around the cooler 40 at positions spaced apart in the longitudinal direction of the cooler 40. The winding sheet 310a is provided with each element (not shown) such as a first bus bar 350a, a signal line 360a, a semiconductor element, and a second bus bar. Similarly, the wound sheet 310b is provided with each element (not shown) such as a first bus bar 350b, a signal line 360b, a semiconductor element, and a second bus bar. The first bus bar 350a and the first bus bar 350b are arranged to extend in opposite directions. The signal line 360a and the signal line 360b are also arranged so as to extend in opposite directions. Therefore, also in the fourth embodiment, a semiconductor module having a large number of semiconductor elements can be manufactured.

(5th Example)
Also in the semiconductor module 402 of the fifth embodiment, two winding sheets 410a and 410b are wound around the cooler 40 as shown in FIG. However, in the fifth embodiment, the first bus bar 450a and the second bus bar (not shown) provided in the winding sheet 410a are arranged on the upper surface side of the cooler 40. On the other hand, the first bus bar 450b and the second bus bar (not shown) provided in the winding sheet 410b are arranged on the side surface side of the cooler 40. The first bus bar 450a and the first bus bar 450b are extended in the same direction. In the fifth embodiment, since the first bus bars 450a and 450b are arranged on different surfaces of the cooler 40, the first bus bars 450a and 450b do not interfere with each other. In the fifth embodiment, a semiconductor module having a large number of semiconductor elements can be manufactured, and the first bus bars 450a and 450b extend in the same direction. Therefore, external wiring to the extended first bus bars 450a and 450b is possible. Can be connected relatively easily.

(Sixth embodiment)
As for the semiconductor module 502 of 6th Example, as shown in FIG. 12, the material of the winding sheet 510 changes with places. That is, in 6th Example, area | region S1 in which the 1st bus-bar 50 is arrange | positioned among the winding sheets 510 is formed with the high heat conductive material (for example, Cu film). Furthermore, an insulating heat conductive resin sheet is provided in a portion in contact with the cooler 40 in the region S1 in order to ensure insulation between the cooler 40 and the first bus bar 50. Therefore, the cooling efficiency of the first bus bar 50 by the cooler 40 is improved, and as a result, the cooling efficiency of the semiconductor element 70 is also improved. Further, in the wound sheet 510, the region S2 in which the second bus bar 80, the semiconductor element 70, and the spring plate 90 are disposed is formed of an insulating resin (for example, polyimide) as in the first embodiment. Further, in the sixth embodiment, in the wound sheet 510, the region S3 in which the pressing plate 98 is disposed is formed of a resin (for example, engineering plastic) having a high hardness at a portion facing the spring plate 90. Therefore, each element of the semiconductor element 70, the first bus bar 50, the signal line 60, and the second bus bar 80 can be more strongly pressed by the pressing plate 98. Therefore, it is possible to reliably connect the elements of the semiconductor element 70, the first bus bar 50, the signal line 60, and the second bus bar 80, and it is also possible to prevent the elements from being displaced from each other.

(Seventh embodiment)
Also in the semiconductor module 602 of the seventh embodiment, the configuration of the winding sheet 610 is different from that of the first embodiment, as shown in FIG. In the winding sheet 10 of the first embodiment, the second bus bar setting portion 18 is provided on the surface side of the element setting portion 22, and the semiconductor element 70 and the second bus bar 80 are provided so as to overlap the front and back surfaces of the winding sheet 10. Yes. Instead, in the winding sheet 610 of the seventh embodiment, as shown in FIG. 13, the second bus bar installation portion is the back surface of the main body 612, and when the winding sheet 610 is wound around the cooler 40, It is formed at a position facing the communication hole 20 provided on the surface side of the element installation portion 22. In this case, by winding the winding sheet 610 around the cooler 40, the conductive layer 82 provided on the back surface of the second bus bar 80 enters the communication hole 20 and contacts the back electrode of the semiconductor element 70. Thereby, also in the seventh embodiment, the back electrode of the semiconductor element 70 and the second bus bar 80 are electrically connected. In the seventh embodiment, the convex portion 92 of the spring plate 90 is pressed against the surface side of the portion of the main body 612 of the winding sheet 610 where the second bus bar 80 is installed.

(Eighth embodiment)
As for the semiconductor module 702 of the eighth embodiment, as shown in FIG. 14, the configuration of the winding sheet 710 is different from that of the first embodiment. In the winding sheet 10 of the first embodiment, the element installation portion 22 is provided on the back side of the main body 12. Instead, in the wound sheet 710 of the eighth embodiment, as shown in FIG. 14, both the element installation portion and the second bus bar installation portion are provided on the surface of the main body 712. In the eighth embodiment, communication holes 720 and 725 are provided in the main body 712 at the position of the element installation portion and the position of the second bus bar installation portion, respectively. A conductive layer 82 provided on the back surface of the second bus bar 80 is disposed in the communication hole 725, and a part of the conductive layer 82 protrudes to the back surface side of the main body 712. Therefore, in the eighth embodiment, by winding the winding sheet 710 around the cooler 40, the conductive layer 52 provided on the surface of the first bus bar 50 enters the communication hole 720 and contacts the surface electrode 74 of the semiconductor element 70. To do. Thereby, also in the eighth embodiment, the surface electrode 74 of the semiconductor element 70 and the first bus bar 50 are electrically connected. Furthermore, by winding the winding sheet 710 around the cooler 40, the conductive layer 82 protruding to the back side of the main body 712 comes into contact with the back electrode of the semiconductor element 70. Thereby, also in the eighth embodiment, the back electrode of the semiconductor element 70 and the second bus bar 80 are electrically connected.

(Ninth embodiment)
In each of the above embodiments, the conductive layer 52 is provided on the surface of the first bus bar 50 (see FIG. 3, FIG. 13, FIG. 14, etc.). In the ninth embodiment, in order to prevent the conductive layer 52 from falling off from the surface of the first bus bar 50 or from being displaced when the winding sheet 10 is wound, a dropping prevention process described below is performed. . In the ninth embodiment, as shown in FIG. 15, an adhesive material 53 is disposed around the conductive layer 52 provided on the surface of the first bus bar 50. The adhesive material 53 temporarily fixes the conductive layer 52 and the surface of the first bus bar 50. Thereby, it is suppressed that the conductive layer 52 falls off from the surface of the first bus bar 50 or is displaced when the winding sheet 10 is wound. In another example, a recess (not shown) for accommodating the back surface side of the conductive layer 52 is formed on the surface of the first bus bar 50, the conductive layer 52 is accommodated in the recess, and is accommodated in the recess. An adhesive material 53 can also be disposed around the conductive layer 52.

  In still another example, as shown in FIGS. 16 and 17, a conductive layer holding portion 14 c is formed in the first bus bar installation portion 14 of the wound sheet 10 in addition to the corner holding portion 14 a and the bus bar insertion portion 14 b. The conductive layer holding part 14c is formed in a cylindrical shape into which the first bus bar 50 can be inserted, similarly to the bus bar insertion part 14b. The conductive layer holding portion 14 has a communication hole 14 d that exposes the central portion 52 of the conductive layer 52. As shown in FIG. 17, the conductive layer 52 of this example includes a flange portion 52b formed thinner than the central portion 52a around the thick central portion 52a. In this example, when the first bus bar 50 is installed in the first bus bar installation portion 14, the surface of the flange portion 52b of the conductive layer 52 is suppressed by the conductive layer holding portion 14c, and the central portion 52a of the conductive layer 52 is The surface is exposed from the communication hole 14d. The surface of the flange portion 52b of the conductive layer 52 is suppressed by the conductive layer holding portion 14c, so that the conductive layer 52 falls off the surface of the first bus bar 50 or is displaced when the winding sheet 10 is wound. Is suppressed.

(Tenth embodiment)
The tenth embodiment is a modification of the seventh embodiment. In the seventh embodiment, the conductive layer 82 is provided on the back surface of the second bus bar 80 (see FIG. 13). In this regard, in the tenth embodiment, a conductive layer 82 is provided on the back electrode of the semiconductor element 70 as shown in FIG. In addition, the conductive layer 82 includes a collar portion 82b formed thinner than the central portion 82a around the thick central portion 82a. In the tenth embodiment, the flange portion 82b of the conductive layer 82 is sandwiched and held between the back electrode of the semiconductor element 70 and the back surface of the main body 612 of the winding sheet 610, and the central portion 82a of the conductive layer 82 is , Projecting to the surface side of the main body 612 through the communication hole 20. In the tenth embodiment, by winding the winding sheet 610 around the cooler 40, the central portion 82 a of the conductive layer 82 protruding to the front surface side of the main body 612 comes into contact with the back surface of the second bus bar 80. In the tenth embodiment, the brim portion 82b of the conductive layer 82 is sandwiched and held between the back electrode of the semiconductor element 70 and the back surface of the main body 612 of the winding sheet 610, so that the conductive layer 82 is held in the semiconductor element 70. Are prevented from falling off from above the back electrode or from being displaced when the winding sheet 610 is wound.

(Eleventh embodiment)
The eleventh embodiment is a modification of the eighth embodiment. In the eighth embodiment, the conductive layer 82 is provided on the back surface of the second bus bar 80, and a part of the conductive layer 82 passes through the communication hole 725 on the back surface side of the main body 712 of the wound sheet 710. It protrudes (see FIG. 14). In this regard, also in the eleventh embodiment, as shown in FIG. 19, the conductive layer 82 includes a flange 82b formed thinner than the central portion 82a around the thick central portion 82a. In the eleventh embodiment, the flange portion 82b of the conductive layer 82 is sandwiched and held between the back surface of the second bus bar 80 and the back surface of the main body 712 of the wound sheet 710, and the central portion 82a of the conductive layer 82 is , Projecting to the back side of the main body 712 through the communication hole 725. In the eleventh embodiment, by winding the winding sheet 710 around the cooler 40, the central portion 82 a of the conductive layer 82 protruding to the back surface side of the main body 712 comes into contact with the back electrode of the semiconductor element 70. In the tenth embodiment, the brim portion 82b of the conductive layer 82 is sandwiched and held between the back surface of the second bus bar 80 and the back surface of the main body 712 of the wound sheet 710, so that the conductive layer 82 is held in the second bus bar. It is possible to prevent falling off from the back surface of 80 or displacement when winding the winding sheet 710.

Modifications of the above embodiments are listed below.
(1) A metal film such as Cu or a metal plate may be further wound around the outer periphery of the wound sheet wound around the cooler. At this time, the winding is performed so as to ensure insulation between the cooler and the module. In that case, heat can be radiated not only from the cooler but also from the wound metal film (metal plate), and the cooling efficiency of the semiconductor element is improved.
(2) A drip-proof sheet may be further wound around the outer periphery of the wound sheet wound around the cooler. This can prevent water droplets from adhering to each element such as a semiconductor element.
(3) An adhesive material may be disposed on a part or the entire surface of the wound sheet. Thereby, when winding a winding sheet around a cooler, the position shift of the winding sheet wound around the cooler can be prevented by fixing the winding sheet with an adhesive.
(4) A wiring pattern may be formed on the winding sheet.
(5) A plurality of semiconductor elements may be installed on one winding sheet. In this case, the plurality of semiconductor elements to be installed may be the same or different from one another.
(6) A positioning pin (protrusion) is provided on one of the cooler and the wrapping sheet, and the pin is fitted when the wrapping sheet is wound on the other of the cooler and the wrapping sheet. May be provided. In this case, when the winding sheet is wound, the pin and the hole are fitted to position the winding sheet. Thereby, the position shift at the time of winding a winding sheet | seat can be prevented.
(7) In each of the above embodiments, a MOSFET is used as a semiconductor element. However, the semiconductor element is not limited to this, and various semiconductor elements such as an IGBT and a diode can be used.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Semiconductor module 10: Winding sheet 12: Body 14: First bus bar installation part 14a: Corner holding part 14b: Bus bar insertion part 14c: Conductive layer holding part 14d: Communication hole 16: Signal line holding part 18: Second bus bar installation Part 18a: Corner holding part 18b: Bus bar insertion part 20: Communication hole 22: Element installation part 24: Spring plate installation part 24a: Corner holding part 26: Through hole 28: Presser plate installation part 28a: Corner holding part 40: Cooler 50: first bus bar 52: conductive layer 53: adhesive material 54: recess 60: signal line 70: semiconductor element 74: surface electrode 76: signal pad 77: insulating layer 80: second bus bar 82: conductive layer 90: spring plate 91 : Main body 92: Convex portion 98: Presser plate 102: Semiconductor modules 170 a to 170 d: Semiconductor element 202: Semiconductor module 240: Cooler 27 a to 270h: semiconductor element 302: semiconductor module 310a, 310b: winding sheet 314a, 314b: first bus bar installation part 350a, 350b: first bus bar 360a, 360b: signal line 402: semiconductor module 410a, 410b: winding sheet 450a, 450b: first bus bar 502: semiconductor module 510: winding sheet 602: semiconductor module 610: winding sheet 612: main body 702: semiconductor module 710: winding sheet 712: main bodies 720, 725: communication holes

Claims (3)

A wrapping sheet;
A member to be wound on which the winding sheet is wound;
A first bus bar installed in a first bus bar installation section of the wound sheet;
A second bus bar installed in a second bus bar installation part of the wound sheet;
A vertical semiconductor element installed in the element installation part of the winding sheet,
When the winding sheet is wound around the member to be wound, one surface of the semiconductor element installed in the element installation unit and the first bus bar installed in the first bus bar installation unit are electrically connected. The other surface of the semiconductor element installed in the element installation part and the second bus bar installed in the second bus bar installation part are electrically connected,
The winding sheet communicates the front surface and the back surface of the winding sheet, and electrically connects one surface of the semiconductor element and the first bus bar, or the other surface of the semiconductor element and the second bus bar. Having a communicating hole,
Semiconductor module. The first bus bar installation part and the second bus bar installation part are provided on one surface of the winding sheet, while the element installation part is provided on the other surface of the winding sheet,
The element installation part is provided at a position facing the first bus bar installation part when the winding sheet is wound around the member to be wound.
The second bus bar installation part is provided on the back side of the element installation part,
The communication hole is provided at a position where the second bus bar installation part and the element installation part communicate with each other.
The other surface of the semiconductor element installed in the element installation part and the second bus bar installed in the second bus bar can be electrically connected through the communication hole.
The semiconductor module according to claim 1. The member to be wound is a cooler.
The semiconductor module according to claim 1 or 2.

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