JP2019033213A - Fixing structure of semiconductor package - Google Patents

Abstract

To enable the extension of an insulation distance from a semiconductor package to a heat sink while keeping a mounting area of the semiconductor package in the heat sink small in a fixing structure of the semiconductor package.SOLUTION: A fixing structure of a semiconductor package is provided, including: a heat sink 1; a first insulation member 5 and a semiconductor package 2 which are provided in layers in this order on a first principal plane 1a of the heat sink; a second insulation member 6 provided on a second principal plane 1b of the heat sink facing opposite from the first principal plane; a conductive male screw member 3 inserted into the semiconductor package, the first insulation member, the heat sink and the second insulation member; a conductive female screw member 4 screwed in the male screw member to pinch the semiconductor package, the first insulation member, the heat sink and the second insulation member in the arrangement direction of them together with the male screw member; and a cylindrical insulation member 7 which is housed in an insertion hole 11 of the heat sink through which the male screw member passes through to cover the inner periphery of the insertion hole and through which the male screw member is inserted .SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor package fixing structure.

  2. Description of the Related Art Conventionally, semiconductor packages that generate heat by energization include one in which a metal part for heat dissipation is exposed on the surface of a resin encapsulating a semiconductor, as in Patent Document 1, for example. In this type of semiconductor package, the metal part is opposed to a metal heat sink, and an insulating member (insulating sheet) is sandwiched between the surface of the semiconductor package including the metal part and the heat sink, and screwed. Fixed to the heat sink. Specifically, an electrically conductive male screw member (for example, a metal male screw member) is inserted into the semiconductor package and the insulating member, and then screwed into the female screw formed on the heat sink, so that the semiconductor package is heat sinked. Fixed to. Accordingly, heat generated in the semiconductor package can be released from the metal portion of the semiconductor package to the heat sink while electrically insulating the metal portion of the semiconductor package and the heat sink.

Japanese Patent Laid-Open No. 07-202090

  By the way, the semiconductor package fixing structure described above has a semiconductor package and a heat sink so that electrical insulation between the semiconductor package and the heat sink can be ensured even if the potential difference between the semiconductor package (particularly the metal portion) and the heat sink increases. There is a need to extend the insulation distance. However, in the conventional semiconductor package fixing structure, since the conductive male screw member is screwed to the heat sink, the male screw member and the heat sink have the same potential. For this reason, the insulation distance between the semiconductor package and the heat sink is only the distance from the metal part of the semiconductor package to the conductive male screw member, which is insufficient.

  Regarding the extension of the insulation distance described above, in the conventional semiconductor package fixing structure, the semiconductor package is sandwiched between the heat sink and the pressing metal, and a conductive male screw member is inserted into the pressing metal at a position away from the semiconductor package. Some are screwed onto the heat sink's internal thread above. In this configuration, since the conductive male screw member can be sufficiently separated from the metal portion of the semiconductor package, the insulation distance between the semiconductor package and the heat sink can be sufficiently extended. However, since the mounting area of the semiconductor package in the heat sink becomes large, it is not preferable.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a semiconductor package fixing structure capable of extending an insulation distance from a semiconductor package to a heat sink while suppressing a mounting area of the semiconductor package in the heat sink. To do.

  One aspect of the present invention includes a heat sink, a first insulating member and a semiconductor package that are sequentially stacked on the first main surface of the heat sink, and a second main surface of the heat sink facing away from the first main surface. A second insulating member disposed on the semiconductor package, a conductive male screw member inserted through the semiconductor package, the first insulating member, the heat sink and the second insulating member; and the male screw member screwed to the male screw member The semiconductor package, the first insulating member, the heat sink and the conductive insulating screw member sandwiching the second insulating member in the arrangement direction, and the insertion hole accommodated in the insertion hole of the heat sink through which the male screw member passes And a cylindrical third insulating member through which the male screw member is inserted, and a semiconductor package fixing structure.

According to the present invention, the male screw member and the heat sink can be electrically insulated by inserting the male screw member so as not to contact the heat sink. Furthermore, an insulating distance between the male screw member and the heat sink can be extended by interposing the cylindrical third insulating member between the inner periphery of the insertion hole of the heat sink and the outer periphery of the male screw member. Thereby, even if the semiconductor package has the metal part for heat radiation exposed to the heat sink side, the insulation distance from the metal part of the semiconductor package to the heat sink can be extended.
In addition, according to the present invention, since the male screw member is inserted into the semiconductor package, the mounting area of the semiconductor package in the heat sink can be reduced compared to the conventional configuration using the presser fitting.

It is sectional drawing which shows the fixing structure of the semiconductor package which concerns on 1st embodiment of this invention. It is sectional drawing which shows the fixing structure of the semiconductor package which concerns on 2nd embodiment of this invention. It is sectional drawing which shows the fixing structure of the semiconductor package which concerns on 3rd embodiment of this invention. It is sectional drawing which shows the fixing structure of the semiconductor package which concerns on 4th embodiment of this invention.

[First embodiment]
A first embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, the semiconductor package fixing structure according to this embodiment includes a heat sink 1, a semiconductor package 2, a male screw member 3, a female screw member 4, and three insulating members 5, 6, 7 (first Insulating member 5, second insulating member 6, and third insulating member 7).

The heat sink 1 is made of a material having conductivity and high thermal conductivity. The heat sink 1 of the present embodiment is formed of a metal such as aluminum. The heat sink 1 is formed with an insertion hole 11 through which the male screw member 3 passes.
The heat sink 1 has two main surfaces 1 a and 1 b (first main surface 1 a and second main surface 1 b) that are opposite to each other in the axial direction of the insertion hole 11. The main surfaces 1a and 1b of the heat sink 1 may be uneven surfaces, for example, but are flat surfaces in this embodiment.

In the present embodiment, an inclined surface 12 is formed between the main surfaces 1 a and 1 b of the heat sink 1 and the inner periphery of the insertion hole 11. The inclined surface 12 extends to the outside of the insertion hole 11 in the radial direction of the insertion hole 11 toward the outside of the insertion hole 11 in the axial direction of the insertion hole 11.
The inclined surface 12 may be formed, for example, in part of the circumferential direction of the insertion hole 11, but is formed in the entire circumferential direction of the insertion hole 11 in this embodiment. Thereby, the end of the insertion hole 11 in the axial direction is formed such that the inner diameter dimension increases toward the outside of the insertion hole 11 in the axial direction. The inclined surface 12 may be formed only at one end portion of the insertion hole 11 in the axial direction, for example, but is formed at both end portions of the insertion hole 11 in the present embodiment.

  The specific shape of the heat sink 1 may be arbitrary. The heat sink 1 of this embodiment is formed in a plate shape. The insertion hole 11 of the heat sink 1 penetrates in the thickness direction of the heat sink 1 (left and right direction in FIG. 1). The two main surfaces 1 a and 1 b of the heat sink 1 are both surfaces facing the thickness direction of the heat sink 1.

The semiconductor package 2 generates heat when energized, such as a power transistor. The semiconductor package 2 is configured by exposing a heat radiating metal portion 22 on the surface of a resin 21 encapsulating a semiconductor element (not shown) as a main heat source. The resin 21 has electrical insulation.
The semiconductor package 2 is formed with an insertion hole 23 (package insertion hole 23) that passes through the resin 21 and the metal portion 22 and through which the male screw member 3 passes. The metal part 22 is covered with the resin 21 so as not to be exposed on the inner periphery of the package insertion hole 23.

  A portion of the semiconductor package 2 including the resin 21 and the metal portion 22 constitutes a package body 20. The exposed surface 20a of the package body 20 including the surface of the metal part 22 exposed from the surface of the resin 21 and the surface of the resin 21 from which the metal part 22 is exposed may be, for example, a surface having irregularities. Then, it is a flat surface.

The semiconductor package 2 of the present embodiment further includes a lead 24 that is electrically connected to the semiconductor element and extends from the package body 20 (resin 21). In the present embodiment, the leading end portion of the lead 24 is connected to the circuit board 100 (through-hole connection in the illustrated example).
In the semiconductor package 2 of the present embodiment, the package body 20 is formed in a plate shape. The exposed surface 20 a of the package body 20 is a surface facing the plate thickness direction of the package body 20. The package insertion hole 23 penetrates in the thickness direction of the package body 20. The lead 24 extends from the side surface 20b of the package body 20 (resin 21) facing in a direction orthogonal to the exposed surface 20a.

The first insulating member 5 has electrical insulation and is sandwiched between the first main surface 1a of the heat sink 1 and the semiconductor package 2 (first semiconductor package 2A). That is, the first insulating member 5 and the first semiconductor package 2 </ b> A are arranged in order on the first main surface 1 a of the heat sink 1.
The first semiconductor package 2 </ b> A is arranged so that the exposed surface 20 a (metal part 22) of the package body 20 faces the first insulating member 5. That is, the first insulating member 5 is sandwiched between the heat sink 1 and the exposed surface 20 a of the package body 20. The first insulating member 5 may cover at least the surface of the metal part 22 in the exposed surface 20a. The first insulating member 5 of the present embodiment covers the entire exposed surface 20a.
In the present embodiment, the leads 24 of the first semiconductor package 2 </ b> A are located at a distance from the first main surface 1 a of the heat sink 1. For this reason, the first insulating member 5 also covers a region of the first main surface 1 a of the heat sink 1 that faces the leads 24.

  The first insulating member 5 is preferably formed so that the heat of the first semiconductor package 2A can be efficiently transmitted to the heat sink 1. In the present embodiment, the first insulating member 5 is an insulating sheet. The first insulating member 5 may have flexibility, for example.

  A through hole 51 through which the male screw member 3 passes is formed in the first insulating member 5. The edge 52 of the through hole 51 of the first insulating member 5 is located outside the inner periphery of the insertion hole 11 in the radial direction of the insertion hole 11 of the heat sink 1 and inside or outside of the inclined surface 12 described above, for example. May be. In the present embodiment, the edge portion 52 of the through hole 51 is located inside the inner periphery of the insertion hole 11 in the radial direction of the insertion hole 11. The edge 52 of the through hole 51 may be positioned inside the package insertion hole 23 of the first semiconductor package 2A in the radial direction as in the illustrated example, but may be positioned outside the package insertion hole 23, for example. .

The second insulating member 6 has electrical insulation and is disposed on the second main surface 1 b of the heat sink 1. In the present embodiment, the second insulating member 6 is sandwiched between the second main surface 1b of the heat sink 1 and the semiconductor package 2 (second semiconductor package 2B), like the first insulating member 5. That is, the second insulating member 6 and the second semiconductor package 2 </ b> B are arranged so as to overlap the second main surface 1 b of the heat sink 1 in order. The arrangement of the second semiconductor package 2B with respect to the heat sink 1 and the second insulating member 6 is the same as the arrangement of the first semiconductor package 2A with respect to the heat sink 1 and the first insulating member 5.
The second insulating member 6 of the present embodiment is configured in the same manner as the first insulating member 5. That is, the second insulating member 6 is an insulating sheet. The second insulating member 6 has a through hole 61 through which the male screw member 3 passes. The positions of the edge portions 62 of the through holes 61 of the second insulating member 6 with respect to the insertion holes 11 of the heat sink 1 and the package insertion holes 23 of the semiconductor package 2 are the same as in the case of the first insulating member 5.

The male screw member 3 has conductivity, and is inserted through the first semiconductor package 2A, the first insulating member 5, the heat sink 1, the second insulating member 6, and the second semiconductor package 2B. The male screw member 3 of the present embodiment is made of metal.
The male screw member 3 may be configured by, for example, a shaft portion (screw rod) on which a male screw is formed and a nut screwed to the shaft portion. The male screw member 3 of the present embodiment includes a shaft portion 31 on which a male screw is formed, and a head portion 32 that is integrally formed on one end of the shaft portion 31.

  The shaft portion 31 of the male screw member 3 may be passed through the insertion hole 11 of the heat sink 1 from the second main surface 1b side of the heat sink 1, for example, but in this embodiment, the insertion hole is inserted from the first main surface 1 a side of the heat sink 1. 11 is passed. In this state, for example, the head 32 of the male screw member 3 may directly contact the surface of the resin 21 of the first semiconductor package 2A (the surface of the package body 20 facing away from the exposed surface 20a). In the illustrated example, a washer 33 and a spring washer 34 are interposed between the head 32 of the male screw member 3 and the surface of the resin 21 of the first semiconductor package 2A.

The female screw member 4 has conductivity. The female screw member 4 of this embodiment is a metal nut. The female screw member 4 is screwed to the male screw member 3 described above, and together with the male screw member 3 (head 32), the first semiconductor package 2A, the first insulating member 5, the heat sink 1, the second insulating member 6, and the second semiconductor package. 2B is sandwiched between these arrangement directions.
In the present embodiment, the female screw member 4 is screwed to the shaft portion 31 of the male screw member 3 protruding from the second semiconductor package 2B. In this state, for example, the female screw member 4 may directly contact the surface of the resin 21 of the second semiconductor package 2B (the surface of the package body 20 facing away from the exposed surface 20a). In the illustrated example, a washer 43 is interposed between the female screw member 4 and the surface of the resin 21 of the second semiconductor package 2B.

  The third insulating member 7 has electrical insulation and is formed in a cylindrical shape. The third insulating member 7 is accommodated in the insertion hole 11 so as to cover the inner periphery of the insertion hole 11 of the heat sink 1. That is, the third insulating member 7 is an insulating bush that fills a partial space of the insertion hole 11. The above-described male screw member 3 (shaft portion 31) is inserted into the third insulating member 7.

  In the present embodiment, both end portions of the third insulating member 7 in the axial direction are located inside the inclined surface 12 described above in the radial direction. That is, the third insulating member 7 of the present embodiment also covers the inclined surface 12. In the present embodiment, the dimension (axial dimension) of the third insulating member 7 in the axial direction is set to be equal to the thickness dimension of the heat sink 1 or slightly smaller than the thickness dimension of the heat sink 1.

  The third insulating member 7 may be fitted into the insertion hole 11 of the heat sink 1, for example. That is, the outer periphery of the third insulating member 7 may contact the inner periphery of the insertion hole 11. In this state, the third insulating member 7 may be fixed to the heat sink 1, for example. In the present embodiment, the third insulating member 7 is arranged with an interval from the inner periphery of the insertion hole 11. That is, the outer diameter dimension of the third insulating member 7 is set smaller than the inner diameter dimension of the insertion hole 11.

  The third insulating member 7 may be formed of any material. The third insulating member 7 of this embodiment is formed of a hard resin such as polycarbonate (PC), polybutylene terephthalate (PBT), or polypropylene terephthalate (PPT).

The edge portion 52 of the through hole 51 of the first insulating member 5 described above may be positioned outside the outer periphery of the third insulating member 7 described above in the radial direction, for example. In the present embodiment, the edge 52 of the through hole 51 of the first insulating member 5 is located on the inner side of the outer periphery of the third insulating member 7 in the radial direction, and the axis of the insertion hole 11 with respect to the third insulating member 7. It is arranged in the direction. For example, the edge 52 of the through hole 51 of the first insulating member 5 may be positioned on the inner side of the inner periphery of the third insulating member 7 in the radial direction, but is not limited thereto.
The position of the edge 62 of the through hole 61 of the second insulating member 6 with respect to the third insulating member 7 is the same as that of the first insulating member 5 described above.

  In the semiconductor package fixing structure of the present embodiment, the heat sink 1 is disposed on the circuit board 100. For this reason, the heat of the semiconductor package 2 may be released to the circuit board 100 via the heat sink 1, for example.

  As described above, according to the semiconductor package fixing structure of the present embodiment, the male screw member 3 is inserted into the insertion hole 11 of the heat sink 1 without being screwed to the heat sink 1 as in the prior art. For this reason, electrical insulation between the male screw member 3 and the heat sink 1 can be achieved by inserting the male screw member 3 so as not to contact the heat sink 1. Furthermore, the cylindrical third insulating member 7 is interposed between the inner periphery of the insertion hole 11 of the heat sink 1 and the outer periphery of the male screw member 3 (particularly the shaft portion 31), so that the space between the heat sink 1 and the male screw member 3 is reduced. The insulation distance can be extended. From the above, the insulation distance from the metal part 22 of the semiconductor package 2 to the heat sink 1 can be extended.

  Further, according to the semiconductor package fixing structure of the present embodiment, the male screw member 3 is inserted through the semiconductor package 2. For this reason, the mounting area of the semiconductor package 2 in the heat sink 1 can be reduced as compared with the conventional configuration using the pressing metal. Further, since the pressing metal fitting is unnecessary, the number of parts constituting the semiconductor package fixing structure can be reduced, and the cost of the product including the semiconductor package fixing structure can be reduced.

  Moreover, according to the semiconductor package fixing structure of the present embodiment, the male screw member 3 and the female screw member 4 are made of metal. The metal male screw member 3 and female screw member 4 have higher strength (for example, strength against external force such as vibration and strength against thermal change) than the male screw member 3 and female screw member 4 made of synthetic resin having electrical insulation. The semiconductor package 2 can be stably fixed to the heat sink 1.

  Further, according to the semiconductor package fixing structure of the present embodiment, the inclined surface 12 is formed between the main surfaces 1 a and 1 b of the heat sink 1 and the inner periphery of the insertion hole 11. For this reason, compared with the case where the inclined surface 12 is not formed, the insulation distance (diameter of the insertion hole 11) from the boundary portion between the main surfaces 1 a and 1 b of the heat sink 1 and the inner periphery of the insertion hole 11 to the male screw member 3. Distance in the direction) can be extended. Therefore, the insulation distance from the semiconductor package 2 to the heat sink 1 can be further extended. In the present embodiment, the boundary between the first insulating member 5 or the second insulating member 6 and the third insulating member 7 is located near the boundary portion between the main surfaces 1 a and 1 b of the heat sink 1 and the inner periphery of the insertion hole 11. Therefore, it is particularly effective to form the inclined surface 12.

Further, according to the semiconductor package fixing structure of the present embodiment, the edge portions 52 and 62 of the through holes 51 and 61 of the first insulating member 5 and the second insulating member 6 are more than the inner periphery of the insertion hole 11 of the heat sink 1. Located inside. For this reason, it is possible to extend the creeping distance from the heat sink 1 to the semiconductor package 2 (particularly the metal portion 22) along the surfaces of the first insulating member 5 and the second insulating member 6.
In addition, according to the semiconductor package fixing structure of the present embodiment, the edges 52 and 62 of the through holes 51 and 61 of the first insulating member 5 and the second insulating member 6 in the axial direction of the insertion hole 11 are the third insulating member. 7 overlaps. For this reason, the clearance between the first insulating member 5 or the second insulating member 6 and the third insulating member 7 can be reduced or eliminated by the tightening force of the male screw member 3 and the female screw member 4. Thereby, the insulation distance from the heat sink 1 to the semiconductor package 2 can be further extended.

  Also, according to the semiconductor package fixing structure of the present embodiment, the first semiconductor package 2A, the first insulating member 5, the heat sink 1, the second insulating member 6 and the first screw member 3 and the female screw member 4 are arranged in order. Two semiconductor packages 2B are sandwiched. For this reason, the two semiconductor packages 2 and 2 can be fixed to both the main surfaces 1 a and 1 b of the heat sink 1 by the single male screw member 3 and the female screw member 4. That is, a larger number of semiconductor packages 2 can be fixed to the heat sink 1 with a smaller number of screwing times compared to the conventional configuration in which the male screw member 3 is screwed to the heat sink 1 to fix the semiconductor package 2 to the heat sink 1. As a result, it is possible to improve the productivity of a product including a semiconductor package fixing structure.

  In the semiconductor package fixing structure of the present embodiment, when the third insulating member 7 is fitted into the insertion hole 11 of the heat sink 1, a gap between the outer periphery of the third insulating member 7 and the inner periphery of the insertion hole 11 is formed. Since the size can be reduced or eliminated, electrical insulation between the male screw member 3 and the heat sink 1 can be further achieved. When the third insulating member 7 is fitted and fixed in the insertion hole 11 of the heat sink 1, the third insulating member 7 is in the axial direction of the insertion hole 11 or perpendicular to the insertion hole 11 of the heat sink 1. It is also possible to prevent displacement in the direction of the movement.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
Below, it demonstrates centering on difference with 1st embodiment, about the component same as 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 2, the semiconductor package fixing structure of the present embodiment has a heat sink 1, a semiconductor package 2, a male screw member 3, a female screw member 4, and three insulating members 5 as in the first embodiment. , 6C, 7C (first insulating member 5, second insulating member 6C, third insulating member 7C). However, in the semiconductor package fixing structure of the present embodiment, the semiconductor package 2 (first semiconductor package 2A) is disposed only on the first main surface 1a side of the heat sink 1 and is not disposed on the second main surface 1b side.

In the present embodiment, the second insulating member 6C disposed on the second main surface 1b side of the heat sink 1 and the cylindrical third insulating member 7C accommodated in the insertion hole 11 of the heat sink 1 are integrally formed. Is formed. That is, the second insulating member 6C and the third insulating member 7C include a cylindrical portion 91C and a flange portion 92C projecting in the radial direction of the cylindrical portion 91C at the first end portion in the axial direction of the cylindrical portion 91C. Insulating bush including.
The second insulating member 6C (flange portion 92C) may be formed in the same sheet shape as in the first embodiment, for example, but in the present embodiment, the second insulating member 6C (flange portion 92C) has an annular shape having a larger thickness than the first insulating member 5. Is formed.

Further, in the present embodiment, the second insulating member 6 </ b> C is formed to a size that covers the region of the second main surface 1 b that overlaps the female screw member 4. That is, the outer diameter dimension of the second insulating member 6C is slightly larger than the outer diameter dimension of the female screw member 4 and the outer diameter dimension of the washer disposed between the female screw member 4 and the second insulating member 6C.
By forming the second insulating member 6 </ b> C as described above, a sufficient insulation distance between the female screw member 4 and the heat sink 1 can be ensured.

According to the semiconductor package fixing structure of the present embodiment, the same effects as those of the first embodiment can be obtained.
Further, according to the semiconductor package fixing structure of the present embodiment, since the second insulating member 6C and the third insulating member 7C are integrally formed, the gap between the second insulating member 6C and the third insulating member 7C. Can be eliminated. Thereby, the insulation distance from the heat sink 1 to the male screw member 3 (particularly the shaft portion 31) can be further extended. Further, since the second insulating member 6C can be disposed on the second main surface 1b of the heat sink 1 simply by inserting the third insulating member 7C into the insertion hole 11 of the heat sink 1, the number of steps for assembling the semiconductor package fixing structure is reduced. It becomes possible to reduce.

  In the second embodiment, for example, the first semiconductor package in which the head 32 of the male screw member 3 is arranged on the second insulating member 6 </ b> C and the female screw member 4 is arranged on the first main surface 1 a side of the heat sink 1. It may be arranged on top of 2A.

  In the second embodiment, for example, similarly to the first embodiment, the second insulating member 6C and the second semiconductor package 2B may be sequentially stacked on the second main surface 1b side of the heat sink 1. In this case, as in the case of the first embodiment, the second insulating member 6C is formed in a sheet shape so as to be interposed between the heat sink 1 and the metal part 22 or the lead 24 of the second semiconductor package 2B. May be.

[Third embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG.
Below, it demonstrates centering on difference with 1st embodiment, about the component same as 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 3, the semiconductor package fixing structure of the present embodiment has a heat sink 1, a semiconductor package 2, a male screw member 3, a female screw member 4, and three insulating members 5 as in the first embodiment. , 6D, 7D (first insulating member 5, second insulating member 6D, third insulating member 7D). However, in the semiconductor package fixing structure of the present embodiment, the semiconductor package 2 (first semiconductor package 2A) is disposed only on the first main surface 1a side of the heat sink 1 and is not disposed on the second main surface 1b side.

In the present embodiment, the second insulating member 6D disposed on the second main surface 1b of the heat sink 1 includes the sandwiched portion 63D and the surrounding portion 64D.
The sandwiched portion 63 </ b> D is sandwiched between the second main surface 1 b of the heat sink 1 and the female screw member 4. A through hole 61D through which the male screw member 3 passes is formed in the sandwiched portion 63D. The shape and size of the sandwiched portion 63D may be arbitrary. The sandwiched portion 63 </ b> D of the present embodiment is formed in an annular shape having a larger thickness than the first insulating member 5.

The surrounding portion 64 </ b> D extends from the sandwiched portion 63 </ b> D in the insertion direction of the male screw member 3 and surrounds the female screw member 4. The shape and size of the surrounding portion 64D may be arbitrary. The surrounding portion 64D of the present embodiment extends in a direction away from the second main surface 1b of the heat sink 1 at the periphery of the sandwiched portion 63D formed in an annular shape.
That is, the second insulating member 6D of the present embodiment is formed in a bottomed cylindrical shape that accommodates the female screw member 4, and a through hole 61D through which the male screw member 3 passes through the bottom of the second insulating member 6D that is the sandwiched portion 63D. Is formed.

  The second insulating member 6D may be formed separately from the third insulating member 7D, for example, as in the first embodiment, but in this embodiment, the second insulating member 6D is formed integrally with the third insulating member 7D as in the second embodiment. ing.

According to the semiconductor package fixing structure of the present embodiment, the same effects as those of the first and second embodiments can be obtained.
Further, according to the semiconductor package fixing structure of the present embodiment, the female screw member 4 is arranged inside the surrounding portion 64D of the second insulating member 6D, so that the heat sink 1 (particularly the second main surface 1b) and the female screw are arranged. The insulation distance with the member 4 can be extended. Thereby, the insulation distance between the heat sink 1 and the external thread member 3 can be extended.

  In the third embodiment, for example, the head 32 of the male screw member 3 is arranged inside the surrounding portion 64D of the second insulating member 6D, and the female screw member 4 is arranged on the first main surface 1a side of the heat sink 1. One semiconductor package 2 </ b> A may be arranged in an overlapping manner. In this case, the insulation distance between the heat sink 1 and the head 32 of the male screw member 3 can be extended.

  In the third embodiment, for example, similarly to the first embodiment, the second insulating member 6D and the second semiconductor package 2B may be sequentially stacked on the second main surface 1b side of the heat sink 1. In this case, the sandwiched portion 63D of the second insulating member 6D is located between the heat sink 1 and the metal portion 22 or the lead 24 of the second semiconductor package 2B, similarly to the second insulating member 6 of the first embodiment. It may be formed in a sheet shape so as to be interposed. Further, the surrounding portion 64D of the second insulating member 6D may be formed so as to surround the second semiconductor package 2B (particularly the package body 20) together with the female screw member 4 (or the head portion 32 of the male screw member 3).

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG.
Below, it demonstrates centering on difference with 1st embodiment, about the component same as 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

As shown in FIG. 4, the semiconductor package fixing structure of the present embodiment has a heat sink 1, a semiconductor package 2, a male screw member 3, a female screw member 4E, and three insulating members 5 as in the first embodiment. 6, 7 (first insulating member 5, second insulating member 6, third insulating member 7).
However, in the semiconductor package fixing structure of the present embodiment, a plurality of female screw holes 44E for screwing the male screw member 3 into the same female screw member 4E are formed.

  The shape of the female screw member 4E may be arbitrary. The surface of the female screw member 4E facing the main surface 1b (second main surface 1b) of the heat sink 1 may be a surface having irregularities, for example, but is a flat surface in this embodiment. The female screw member 4E of the present embodiment is formed in a flat plate shape. The plurality of female screw holes 44E penetrates in the thickness direction of the female screw member 4E.

  A plurality of insertion holes 11 are formed in the heat sink 1 of the present embodiment. The plurality of insertion holes 11 are formed at positions corresponding to the plurality of female screw holes 44E of the female screw member 4E. The third insulating members 7 are accommodated one by one in the plurality of insertion holes 11. Although the inclined surface 12 (refer FIG. 1) is not formed in the heat sink 1 of the example of illustration, it may form, for example.

A plurality of through holes 51 are formed in the first insulating member 5 disposed on the first main surface 1 a of the heat sink 1. The plurality of through holes 51 are formed at positions corresponding to the plurality of insertion holes 11 of the heat sink 1.
A plurality of first semiconductor packages 2 </ b> A are arranged on the first insulating member 5 on the first main surface 1 a side of the heat sink 1. The plurality of first semiconductor packages 2 </ b> A are arranged at positions corresponding to the plurality of insertion holes 11 of the heat sink 1. In FIG. 4, illustration of the metal part 22 (refer FIG. 1 etc.) of the 1st semiconductor package 2A is abbreviate | omitted.

A plurality of through holes 61 corresponding to the plurality of insertion holes 11 of the heat sink 1 are formed in the second insulating member 6 disposed on the second main surface 1 b of the heat sink 1, similarly to the first insulating member 5. Yes.
For example, the semiconductor package 2 may not be disposed on the second main surface 1b side of the heat sink 1 as in the second and third embodiments. In this case, the second insulating member 6 and the female screw member 4E are disposed on the second main surface 1b of the heat sink 1 so as to overlap each other. In the present embodiment, as in the first embodiment, a plurality of second semiconductor packages 2 </ b> B are arranged on the second insulating member 6 on the second main surface 1 b side of the heat sink 1. The plurality of second semiconductor packages 2 </ b> B are arranged at positions corresponding to the plurality of insertion holes 11 of the heat sink 1. In FIG. 4, illustration of the metal part 22 (refer FIG. 1 etc.) of the 2nd semiconductor package 2B is abbreviate | omitted.

  The plurality of third insulating members 7 respectively accommodated in the plurality of insertion holes 11 of the heat sink 1 may be formed integrally with the second insulating member 6 as in the second and third embodiments, for example. Then, like the first embodiment, it is formed separately from the second insulating member 6.

According to the semiconductor package fixing structure of this embodiment, the same effects as those of the first and second embodiments can be obtained.
Further, according to the semiconductor package fixing structure of the present embodiment, a plurality of female screw holes 44E for screwing the male screw member 3 into the same female screw member 4E are formed. For this reason, a plurality of semiconductor packages 2 can be fixed to the heat sink 1 using one female screw member 4E.

  Further, when the male screw member 3 is screwed into the female screw hole 44E of the female screw member 4E, the female screw member 4E can be prevented from rotating with respect to the second semiconductor package 2B and the second insulating member 6. For this reason, the female screw member 4E and the second semiconductor package 2B and the second insulating member 6 do not rub against each other. Thereby, the washer (for example, described in FIGS. 1-3) protects the second semiconductor package 2B and the second insulating member 6 from the rubbing between the female screw member 4E and the second semiconductor package 2B and the second insulating member 6. The need for the washer 43) is eliminated. That is, the number of parts constituting the semiconductor package fixing structure can be reduced, and the cost of the product including the semiconductor package fixing structure can be reduced.

  In the fourth embodiment, for example, the heads 32 of the plurality of male screw members 3 are arranged on the second insulating member 6 or the plurality of second semiconductor packages 2B, and the female screw member 4E is the first main member of the heat sink 1. The plurality of first semiconductor packages 2A arranged on the surface 1a side may be overlaid.

  For example, the configuration of the third embodiment may be applied to the configuration of the fourth embodiment. For example, the surrounding portion 64D of the second insulating member 6D of the third embodiment may be formed so as to surround the female screw member 4E and the plurality of second semiconductor packages 2B (particularly the package body 20) of the present embodiment.

  Although the details of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Heat sink 1a 1st main surface 1b 2nd main surface 11 Insertion hole 12 Inclined surface 2 Semiconductor package 2A 1st semiconductor package 2B 2nd semiconductor package 3 Male screw member 31 Shaft part 32 Head part 4, 4E Female screw member 44E Female screw hole 5 1st One insulating member 51 Through-hole 52 Edges 6, 6C, 6D of through-hole 52 Second insulating members 61, 61D Through-hole 62 Edge 63D of through-hole 61 Encased part 64D Surrounding parts 7, 7C, 7D Third insulating member

Claims (7)

A heat sink,
A first insulating member and a semiconductor package, which are sequentially stacked on the first main surface of the heat sink;
A second insulating member disposed on the second main surface of the heat sink facing away from the first main surface;
A conductive male screw member inserted through the semiconductor package, the first insulating member, the heat sink and the second insulating member;
A conductive female screw member that is screwed to the male screw member and sandwiches the semiconductor package, the first insulating member, the heat sink, and the second insulating member together with the male screw member in the arrangement direction;
A semiconductor package fixing structure comprising: a cylindrical third insulating member that is accommodated in an insertion hole of the heat sink through which the male screw member passes and covers an inner periphery of the insertion hole and through which the male screw member is inserted.   Between the main surface of the heat sink and the inner periphery of the insertion hole, there is an inclined surface that extends to the outside of the insertion hole in the radial direction of the insertion hole toward the outside of the insertion hole in the axial direction of the insertion hole. The semiconductor package fixing structure according to claim 1, wherein the semiconductor package fixing structure is formed.   The edge portion of the through hole of the first insulating member through which the male screw member passes is located on the inner side of the inner periphery of the insertion hole in the radial direction of the insertion hole, and is inserted into the insertion hole. The semiconductor package fixing structure according to claim 1, wherein the semiconductor package fixing structure is arranged so as to overlap with an insulating member in an axial direction of the insertion hole.   The semiconductor package fixing structure according to any one of claims 1 to 3, wherein the second insulating member and the third insulating member are integrally formed. The second insulating member is
A sandwiched portion sandwiched between the second main surface of the heat sink and either the head of the male screw member or the female screw member;
The surrounding part which extends in the insertion direction of the said external thread member from the said sandwiched part and surrounds either the head part of the external thread member or the said internal thread member is provided in any one of Claims 1-4. Fixed structure of the semiconductor package as described.   The semiconductor package fixing structure according to any one of claims 1 to 5, wherein a plurality of female screw holes into which the male screw member is screwed are formed in the female screw member. The semiconductor package is also arranged at a position where the second insulating member is sandwiched between the heat sink,
7. The device according to claim 1, wherein the male screw member and the female screw member sandwich the semiconductor package, the first insulating member, the heat sink, the second insulating member, and the semiconductor package that are sequentially arranged in the arrangement direction. The semiconductor package fixing structure according to claim 1.

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