JP2014157954A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an art in a semiconductor device, which is capable of reducing man hour required for an attach/detach work of a fastening jig when bonding a base plate and a case by an adhesive, and capable of securing the base plate and the case with high fastening power.SOLUTION: A semiconductor device comprises: a base plate 1 on which an attachment part having a screw part 1b is formed and a semiconductor element is arranged; a bush 3 capable of being screwed with the attachment part of the base plate 1; and a case 2 in which an insertion hole 2b capable of inserting the bush 3 is formed. Further in the semiconductor device, by screwing the bush 3 to the attachment part of the base plate 1 in a state where the case 2 is placed on the base plate 1, the base plate 1 and the case 2 are secured.

Description

  The present invention relates to improvement of tact time and manufacturing cost in a manufacturing process of a semiconductor device (for example, a power semiconductor device).

  Conventionally, in a manufacturing process of a semiconductor device, when a base plate on which a semiconductor element is arranged and a case are joined with an adhesive, a fastening jig is attached to the product (base plate and case), and this fastening jig is used. The base plate and the case were clamped and fixed by screwing. Since it is necessary to remove the fastening jig from the product after the adhesive is cured, there has been a demand for reducing the number of man-hours required for attaching and detaching the fastening jig.

  Then, when joining a base board and a case, it is possible to fix these using a bush instead of a fastening jig. For example, Patent Document 1 discloses a structure that prevents the knurling bush from falling off the base plate due to the unevenness of the side surface by attaching a knurling bush having unevenness on the side surface to the base plate. It is conceivable to fix the base plate and the case using such a knurling bush. Since a fastening jig is not used when joining the base plate and the case, it is possible to reduce the man-hours required for attaching / detaching the fastening jig.

JP 2006-114641 A

  However, when the base plate and the case are fixed using the knurling bush when the base plate and the case are joined, the knurling bush is simply provided with unevenness on the side surface, so that the fastening force to the base plate and the case is low. There may be a shortage.

  Therefore, the present invention can reduce the number of man-hours required for attaching and detaching the fastening jig when joining the base plate and the case with an adhesive in the semiconductor device, and can provide a high fastening force between the base plate and the case. It aims at providing the technology which can be fixed with.

  The semiconductor device according to the present invention has a base plate on which a mounting portion having a screw portion is formed and a semiconductor element is disposed, a bush that can be screwed to the mounting portion of the base plate, and the bush can be inserted. A case in which a through hole is formed, and in a state where the case is placed on the base plate, the base plate and the case are secured by screwing the bush to the mounting portion of the base plate. It is fixed.

  Another semiconductor device according to the present invention includes a base plate in which a first fitting hole is formed and a semiconductor element is disposed, a bush that can be fitted into the first fitting hole of the base plate, and the bush And a case formed with a second fitting hole in which the upper part of the bush is tightened into the second fitting hole of the case, and the first fitting hole of the base plate is The base plate and the case are fixed by tightening and tightening the lower part of the bush.

  According to the semiconductor device of the present invention, the mounting portion having the screw portion is formed, the base plate on which the semiconductor element is disposed, the bush that can be screwed with the mounting portion of the base plate, and the insertion through which the bush can be inserted. The base plate and the case were fixed by screwing a bush to the mounting portion of the base plate in a state where the case was placed on the base plate.

  Therefore, since the base plate and the case can be fixed without using a fastening jig when the base plate and the case are joined with an adhesive, man-hours required for attaching and detaching the fastening jig can be reduced. it can. Further, since the base plate and the case are fixed by screwing the bush to the mounting portion of the base plate, they can be fixed with a high fastening force.

  According to another semiconductor device of the present invention, a base plate in which a first fitting hole is formed and a semiconductor element is arranged, a bush that can be fitted into the first fitting hole of the base plate, and a bush are fitted. A case formed with a second fitting hole that can be formed, and the upper part of the bush is tightened into the second fitting hole of the case, and the lower part of the bush is tightened into the first fitting hole of the base plate. The base plate and case were fixed.

  Therefore, since the base plate and the case can be fixed without using a fastening jig when the base plate and the case are joined with an adhesive, man-hours required for attaching and detaching the fastening jig can be reduced. it can. In addition, the base plate and the case are fixed by tightening the upper portion of the bush into the second fitting hole of the case and tightening the lower portion of the bush into the first fitting hole of the base plate. These can be fixed with a high fastening force.

3 is a cross-sectional view of a fixing structure between a base plate and a case in the semiconductor device according to the first embodiment. FIG. 6 is a cross-sectional view showing an example of a method for manufacturing a bush in the semiconductor device according to the first embodiment. FIG. FIG. 6 is a cross-sectional view of a fixing structure between a base plate and a case in a semiconductor device according to a second embodiment. FIG. 9 is a cross-sectional view illustrating a method for fixing a base plate and a case in a semiconductor device according to a third embodiment. It is sectional drawing of the fixing structure of the base board and case in the semiconductor device which concerns on a base technology.

<Prerequisite technology>
First, a semiconductor device according to the prerequisite technology will be described. FIG. 5 is a cross-sectional view of the fixing structure of the base plate 101 and the case 102 in the semiconductor device according to the base technology, and shows a state where the base plate 101 and the case 102 are fixed by the fastening jig 106. The semiconductor device according to the base technology includes a copper base plate 101, a resin case 102, and a metal bush 103.

  The base plate 101 is a member for arranging semiconductor elements (not shown), and the case 102 is placed after the adhesive 104 is applied to the upper surface of the base plate 101. A hole 102a is formed in the case 102, and a bush 103 is incorporated in the hole 102a. When the semiconductor device is assembled into an inverter unit or the like after completion of the semiconductor device, a bolt is screwed through the bush 103, and the bush 103 is incorporated for the purpose of protecting the case 102 at this time.

  Next, a manufacturing process for bonding the base plate 101 and the case 102 with the adhesive 104 in the semiconductor device according to the base technology will be described. The base plate 101 is placed on the upper surface of the fastening jig 106, and after the adhesive 104 is applied to the upper surface of the base plate 101, the case 102 is placed. At this time, in order to improve the adhesion between the base plate 101 and the case 102, the base plate 101 and the case 102 are fixed using the fastening jig 106 and the fastening bolt 107.

  Specifically, the tightening bolt 107 is inserted from above into the hole 103 a of the bush 103 incorporated in the case 102 and the insertion hole 101 a of the base plate 101, and a screw is inserted into the screw hole 106 a of the fastening jig 106. By tightening, the base plate 101 and the case 102 are fixed. After the adhesive 104 is cured and adhered by heat, the fastening bolt 107 and the fastening jig 106 are removed from the semiconductor device. As described above, in the semiconductor device according to the base technology, the man-hours required for attaching / detaching the fastening bolt 107 and the fastening jig 106 are required.

<Embodiment 1>
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a fixing structure between a base plate 1 and a case 2 in the semiconductor device according to the first embodiment. The semiconductor device includes a copper base plate 1, a resin case 2, and a bush 3. The bush 3 has a head portion 3a and a screw portion 3b in the same manner as a normal bolt, and further, for example, an insertion hole 3c extending in the axial direction is formed in the bush 3 by drilling the bolt. ing. The insertion hole 3c is formed so that a bolt that is screwed when the semiconductor device is assembled into an inverter unit or the like after completion of the semiconductor device can be inserted. Here, the material of the bush 3 is optimally a metal such as brass or aluminum which has good workability and is inexpensive in material cost.

  The base plate 1 is formed with an attachment hole 1a (attachment portion) having a screw portion 1b into which the screw portion 3b of the bush 3 can be screwed. The case 2 is formed so that a counterbore 2a that can accommodate the head 3a of the bush 3 and an insertion hole 2b through which the screw portion 3b of the bush 3 can be inserted.

  Next, a manufacturing process for joining the base plate 1 and the case 2 in the semiconductor device according to the first embodiment with the adhesive 4 will be described. After the adhesive 4 is applied to the upper surface of the base plate 1, the case 2 is placed with its position aligned so that the mounting hole 1a and the insertion hole 2b communicate with each other. At this time, in order to improve the adhesion between the base plate 1 and the case 2, the base plate 1 and the case 2 are fixed using the bush 3. Specifically, from above, the bush 3 is inserted into the insertion hole 2b of the case 2 and is screwed into the mounting hole 1a of the base plate 1 so that the base plate 1 and the case 2 are fixed.

  As described above, in the semiconductor device according to the first embodiment, the mounting hole 1a having the screw portion 1b is formed, and the base plate 1 on which the semiconductor element is disposed, and the mounting hole 1a of the base plate 1 are screwed together. And a case 2 having an insertion hole 2b through which the bush 3 can be inserted, and the bush 3 is inserted into the insertion hole 2b of the case 2 with the case 2 placed on the base plate 1. At the same time, the base plate 1 and the case 2 were fixed by screwing the bush 3 into the mounting hole 1 a of the base plate 1.

  Accordingly, since the base plate 1 and the case 2 can be fixed without using a fastening jig when the base plate 1 and the case 2 are joined with an adhesive, man-hours required for attaching and detaching the fastening jig are reduced. Can be reduced. Moreover, since the base plate 1 and the case 2 are fixed by screwing the bush 3 into the mounting hole 1a of the base plate 1, they can be fixed with a high fastening force. In this way, since the base plate 1 and the case 2 can be fixed and joined with a high fastening force, the case 2 can be prevented from being detached from the base plate 1, and the yield of the semiconductor device can be improved.

  The bush 3 is not manufactured in advance, but is drilled in the axial direction of the bolt 10 with the bolt 10 screwed into the mounting hole 1a of the base plate 1 as shown in FIG. It may be formed by applying. FIG. 2 is a cross-sectional view showing an example of a manufacturing method of the bush 3 in the semiconductor device according to the first embodiment.

  A method of manufacturing the bush 3 in this case will be briefly described. When joining the base plate 1 and the case 2 with an adhesive, the bolt 10 is inserted into the insertion hole 2b of the case 2 and screwed into the mounting hole 1a of the base plate 1. Thereafter, the drill 11 is drilled in the axial direction of the bolt 10, thereby forming the insertion hole 3 c and manufacturing the bush 3. As described above, since the bush 3 is also manufactured together when the base plate 1 and the case 2 are fixed, it is not necessary to prepare the bush 3 in advance before assembling the semiconductor device.

<Embodiment 2>
Next, a semiconductor device according to the second embodiment will be described. FIG. 3 is a cross-sectional view of a fixing structure between the base plate 21 and the case 2 in the semiconductor device according to the second embodiment. In the second embodiment, the same components as those described in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The semiconductor device according to the second embodiment includes a copper base plate 21, a resin case 2, and a bush 23. The base plate 21 is formed with an insertion hole 21a into which a bolt to be screwed when the semiconductor device is assembled into an inverter unit or the like after the semiconductor device is completed. In the base plate 21, a protrusion 21 b (attachment portion) that protrudes toward the case 2 (upward) is formed at the periphery of the insertion hole 21 a. In a state where the protrusion 21 b of the base plate 21 is inserted into the insertion hole 2 b of the case 2 and the case 2 is placed on the base plate 21, the tip of the protrusion 21 b is formed above the insertion hole 2 b of the case 2. Located in the counterbore 2a. A screw portion 21c is formed on the outer peripheral surface of the protruding portion 21b.

  The bush 23 is a nut-type bush, and a screw portion 23a that can be screwed with the screw portion 21c of the protruding portion 21b is formed on the inner peripheral surface. The bush 23 is configured such that the lower end of the bush 23 is in contact with the bottom surface of the counterbore 2a in a state in which the bush 23 is screwed to the protruding portion 21b. For this reason, the base plate 21 and the case 2 are fixed with a high fastening force by screwing the bush 23 to the protrusion 21b.

  Next, a manufacturing process for joining the base plate 21 and the case 2 in the semiconductor device according to the second embodiment with the adhesive 4 will be described. After applying the adhesive 4 to the upper surface of the base plate 21, the case 2 is placed at a position where the protruding portion 21 b of the base plate 21 is inserted into the insertion hole 2 b of the case 2. At this time, in order to improve the adhesion between the base plate 21 and the case 2, the base plate 21 and the case 2 are fixed using the bush 23. Specifically, with the protrusion 21b of the base plate 21 inserted into the insertion hole 2b of the case 2, the base plate 21 and the case 2 are fixed by screwing the bush 23 onto the protrusion 21b from above. The

  As described above, in the semiconductor device according to the second embodiment, the mounting portion is the protrusion 21 b formed on the base plate 21, the bush 23 is a nut-type bush, and the base is located in the insertion hole 2 b of the case 2. The base plate 21 and the case 2 were fixed by screwing the bush 23 to the protrusion 21b with the protrusion 21b of the plate 21 inserted.

  Therefore, as in the case of the first embodiment, the base plate 21 and the case 2 can be fixed without using a fastening jig when the base plate 21 and the case 2 are joined with an adhesive. Man-hours required for attaching / detaching the fastening jig can be reduced. Moreover, since the base plate 21 and the case 2 are fixed by screwing the bush 23 to the protruding portion 21b of the base plate 21, they can be fixed with a high fastening force.

<Embodiment 3>
Next, a semiconductor device according to the third embodiment will be described. FIG. 4 is a cross-sectional view of a fixing structure between the base plate 31 and the case 32 in the semiconductor device according to the third embodiment. In the third embodiment, the same components as those described in the first and second embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  The semiconductor device according to the third embodiment includes a copper base plate 31, a resin case 32, and a bush 33. The bush 33 is formed in a cylindrical shape, and the bush 33 is formed with an insertion hole 33a in the axial direction through which a bolt to be screwed can be inserted when the semiconductor device is assembled into an inverter unit or the like after the semiconductor device is completed. . Here, the material of the bush 33 is optimally copper like the base plate 31.

  The base plate 31 is formed with a fitting hole 31a (first fitting hole) into which the lower portion of the bush 33 can be fitted. The case 32 is formed with a fitting hole 32a (second fitting hole) into which the upper portion of the bush 33 can be fitted. The diameters of the fitting hole 31a of the base plate 31 and the fitting hole 32a of the case 32 are formed to be slightly smaller than the outer diameter of the bush 33, respectively. For this reason, the base plate 31 and the case 32 are fixed by tightening the upper portion of the bush 33 into the fitting hole 32a of the case 32 and tightening the lower portion of the bush 33 into the fitting hole 31a of the base plate 31. The

  Next, a manufacturing process for joining the base plate 31 and the case 32 in the semiconductor device according to the third embodiment with the adhesive 4 will be described. For example, the upper portion of the bush 33 is clamped in advance into the fitting hole 32 a of the case 32 by a press 34. In this state, the lower portion of the bush 33 protrudes from the lower surface of the case 32. After the adhesive 4 is applied to the upper surface of the base plate 31, the lower portion of the bush 33 is pushed from above by the press 34 with the fitting hole 31a of the base plate 31 and the lower end of the bush 33 aligned. By inserting in, the lower part of the bush 33 and the fitting hole 31a are tightened. Thereby, the base plate 31 and the case 32 are fixed.

  As described above, in the semiconductor device according to the third embodiment, the fitting hole 31a is formed, and the base plate 31 on which the semiconductor element is arranged, and the bush 33 that can be fitted into the fitting hole 31a of the base plate 31. And a case 32 in which a fitting hole 32 a into which the bush 33 can be fitted is formed. The upper portion of the bush 33 is tightened into the fitting hole 32 a of the case 32, and the bush is inserted into the fitting hole 31 a of the base plate 31. The base plate 31 and the case 32 were fixed by tightening and tightening the lower part of 33.

  Therefore, as in the first and second embodiments, the base plate 31 and the case 32 can be fixed without using a fastening jig when the base plate 31 and the case 32 are joined with the adhesive 4. Therefore, man-hours required for attaching / detaching the fastening jig can be reduced. The base plate 31 and the case 32 are fixed by tightening the upper portion of the bush 33 into the fitting hole 32a of the case 32 and tightening the lower portion of the bush 33 into the fitting hole 31a of the base plate 31. Therefore, they can be fixed with a high fastening force.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  1 Base plate, 1a Mounting hole, 1b Screw part, 2 case, 2b Insertion hole, 3 Bush, 21 Base plate, 21b Projection part, 21c Screw part, 23 Bush, 31 Base plate, 31a Fitting hole, 32 Case, 32a Fitting hole, 33 bush.

Claims (5)

A base plate on which a mounting portion having a screw portion is formed and a semiconductor element is disposed;
A bushing screwable with the mounting portion of the base plate;
And a case formed with an insertion hole through which the bush can be inserted,
A semiconductor device in which the base plate and the case are fixed by screwing the bush to the mounting portion of the base plate in a state where the case is placed on the base plate. The mounting portion is a mounting hole formed in the base plate,
The semiconductor device according to claim 1, wherein the base plate and the case are fixed by inserting the bush into the insertion hole of the case and screwing the bush into the mounting hole of the base plate.   The semiconductor device according to claim 2, wherein the bush is formed by drilling in a direction of an axis of the bolt in a state where a bolt is screwed into the mounting hole of the base plate. The mounting portion is a protrusion formed on the base plate,
The bush is a nut-type bush;
2. The semiconductor according to claim 1, wherein the base plate and the case are fixed by screwing the bush to the protrusion in a state where the protrusion of the base plate is inserted into the insertion hole of the case. apparatus. A base plate on which a first fitting hole is formed and a semiconductor element is disposed;
A bush that can be fitted into the first fitting hole of the base plate;
A case formed with a second fitting hole into which the bush can be fitted,
The base plate and the case are fixed by tightening the upper portion of the bush into the second fitting hole of the case and tightening the lower portion of the bush into the first fitting hole of the base plate. A semiconductor device.

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