JPH09134985A - Mounting structure of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the mounting work of a semiconductor device as to the mounting structure of a semiconductor device in which the semiconductor device is mounted on a radiator fin. SOLUTION: This structure has an insulation holding member 3 in which a recessed part 3a for receiving a semiconductor device 1 with a lead 2 led out from one end of a mold case having a mounting hole 1a and a nearly flat foe a plate spring 5 disposed in the recessed part 3a to press the semiconductor device 1 against a radiator fin 6 in mounting the insulation holding member 3 on the radiator fin 6 and a supporting rod 4 projecting into the recessed part 3a and inserted into the elongated hole 5a of the plate spring 5 and the mounting hole 1a of the semiconductor device 1. The expansible head part 4a of the tip of the supporting rod 4 is passed through an insertion hole 6a formed in the radiator fin 6, thereby mounting the insulation holding member 3 on the radiator fin 6. 7 denotes a thermal sheet and 8 denotes a printed circuit board.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device mounting structure for mounting a semiconductor device on a radiation fin. Semiconductor devices for high power include, for example, SC-65 and SC-6.
A relatively flat mold case such as 7, TO-220, TO-3P, etc., in which leads are led out from one end is relatively often used, and the flat portion is attached to a heat radiation fin. Further, due to the height limitation and the like for downsizing the housing, the semiconductor device is mounted in a narrow space, which causes a problem of workability.

[0002]

2. Description of the Related Art FIG.
Reference numeral 2 is a semiconductor device, 53 is a thermal sheet, 54 is a radiating fin, 55 is an insulating sheet, 56 is a mounting bracket, 57 is a mounting screw, 58 is a screw hole, and 59 is an insertion hole. Shows the case of mounting.

The semiconductor devices 51 and 52 are semiconductor devices, such as high-power power transistors and high-current switching FETs, which generate a large amount of heat, and as described above, SC-6.
5, SC-67, TO-220, TO-3P and the like, the lead is led out from one end of a substantially flat mold case, and a mounting hole is formed in the mold case. A case is also known in which this mounting hole is not formed.

These semiconductor devices 51 and 52 are arranged on the heat radiation fins 54 via the thermal sheet 53 and on the mounting metal fittings 56 via the insulating sheet 55. The mounting metal fitting 56 is fastened to the radiation fin 54 so that the two semiconductor devices 51, 52
Is attached to the radiation fin 54. The leads of the semiconductor devices 51 and 52 are inserted into through holes of a printed circuit board (not shown) and connected to the printed wiring.

[0005]

In the conventional semiconductor device mounting structure, the insulating sheet 55 is interposed between the plurality of semiconductor devices 51 and 52 and the mounting bracket 56 for mounting the radiation fins 54. Since the height of the radiation fin 54 is limited as the device becomes smaller, the semiconductor devices 51 and 52 are arranged within a narrow range, and the mounting bracket 5 is installed.
6, the insulating sheet 55 is interposed, and the mounting screw 57
Will be fastened to the screw hole 58 of the heat radiation fin 54, and the work of attaching the semiconductor devices 51 and 52 to the heat radiation fin 54 is not easy.

Since the mounting screw 57 is made of metal, the standard (UL) is set so that the distance between the mounting screw 57 and the semiconductor devices 51 and 52 is, for example, 4 mm or more.
1950, IEC950) is known. In order to satisfy this standard, the semiconductor devices 51 and 52 should be arranged 8 mm or more apart from each other, so that there is a problem that miniaturization cannot be achieved even if the heat radiation conditions are satisfied. It is an object of the present invention to simplify the work of mounting a semiconductor device and reduce the size thereof.

[0007]

The semiconductor device mounting structure according to the present invention is as follows: (1) The semiconductor device 1 in which the lead 2 is led out from one end of a substantially flat mold case having the mounting hole 1a is mounted on the heat radiation fin 6. In the mounting structure of a semiconductor device to be mounted, an insulating holding member 3 having a recess 3a for housing the semiconductor device 1 and a recess 3a of the insulating holding member 3 are formed.
Of the semiconductor holding device 3 and the insulating holding member 3 attached to the heat radiation fins 6, the leaf springs 5 for pressing the semiconductor device 1 against the heat radiation fins, and the recesses 3a of the insulating holding member 3 are protruded. It is provided with a support rod 4 which is inserted into the mounting hole 1a to support the semiconductor device 1.

(2) Further, the support rod 4 projects from the concave portion 3a of the insulating holding member 3, and the insulating holding member 3 is radiated by the heat radiation fins 6.
It has an expansion / contraction head 4a at its tip end portion, which penetrates the insertion hole 6a formed in the heat radiation fin 6 to prevent it from coming off when it is pressed against.

(3) Further, the support rods penetrate the insertion hole formed in the insulating holding member 3, the mounting hole 1a of the semiconductor device 1 and the insertion hole 6a formed in the heat radiation fin 6, respectively, to prevent the support rod from coming off. It is possible to have a configuration in which both ends have expansion / contraction heads.

(4) Also, a recess for accommodating the semiconductor device 1,
An insulating holding member having an extension attached to the radiation fin and an insulating holding member disposed in the recess of the insulating holding member. When the extension of the insulating holding member is attached to the radiation fin, the semiconductor device is attached to the radiation fin. It is possible to adopt a configuration including a leaf spring for pressing to the above, and a support rod that projects into the recess of the insulating holding member and is inserted into the mounting hole of the semiconductor device to support the semiconductor device.

(5) In the above structure, the support rod has a length which does not protrude from the mounting hole of the semiconductor device when protruding from the concave portion of the insulating holding member and when the extended portion of the insulating holding member is attached to the radiation fin. Can be set to.

[0012]

1 is a cross-sectional view of the essential parts of a first embodiment of the present invention, in which 1 is a semiconductor device, 1a is a mounting hole, 2 is a lead, 3 is an insulating holding member, 3a is a recess, and 4 is a recess. Support rod, 4a
Is an expansion / contraction head, 4b is a split groove, 5 is a leaf spring, 6 is a radiation fin, 6a is an insertion hole, 7 is a thermal sheet, 8 is a printed circuit board, and 9 is a screw. Further, as shown in the lower part, the leaf spring 5 has a long hole 5a through which the support rod 4 penetrates, so that the side edges 5b, 5
c and the edges 5d and 5e, the edges 5d,
5e is held by the groove on the wall surface of the recess 3a of the insulating holding member 3.

FIG. 2 is a perspective view of an insulation holding member according to the first embodiment of the present invention. An insulation holding member 3 made of synthetic resin or the like has a recess 3a for accommodating the semiconductor device 1 and a partition 3b. The side wall portions 3c and 3d and the upper wall portion 3e are formed. Further, the support rod 4 is integrally formed so as to project into the recess 3a, and the leaf spring 5 is arranged in the recess 3a.

The support rod 4 is formed integrally with the insulation holding member 3, and as shown in FIG. 1, the tip portion can be reduced by the split groove 4b, and after penetrating the hole, it is expanded to prevent coming off. It has an expanding / contracting head 4a. Also leaf spring 5
In the state where the support rod 4 penetrates the long hole 5a, the end sides 5d and 5e are held by the groove of the wall surface of the recess 3a of the insulating holding member 3, and the semiconductor device 1 is held by the side sides 5b and 5c.
Is pressed to the heat radiation fin 6 side.

In the state shown in FIG. 2, the support rod 4 is penetrated through the mounting hole 1a of the semiconductor device 1 and the thermal sheet 7 is formed.
When the support rod 4 is penetrated through the insertion hole 6a formed in the heat radiation fin 6 with the interposition of, the expansion / contraction head 4a expands after penetrating the insertion hole 6a to prevent coming off. Since the semiconductor device 1 can be attached to the radiation fin 6, the semiconductor device 1 can be easily attached to the radiation fin 6. Further, the side edges 5b and 5c of the leaf spring 5 allow the semiconductor device 1 to be pressed against the heat radiation fin 6 on average, and the semiconductor device 1 can be attached to the heat radiation fin 6 with low thermal resistance.

Then, the leads 2 of the semiconductor device 1 are inserted into the through holes of the printed board 8 and the printed board 8 is inserted.
By fixing the radiation fin 6 with the screw 9,
The configuration shown in the cross-sectional view of the main part of FIG. 1 is obtained. In this case, since the semiconductor device 1 and the heat radiation fin 6 are not attached by screws, the semiconductor device 1 can be attached to the heat radiation fin 6 even in a narrow space. Two semiconductor devices 1
Since there is no metal screw or the like between them and only the partition wall 3b of the insulation holding member 3 is present, the partition wall 3b can be made thin, and the overall size can be reduced.

When it is necessary to remove the semiconductor device 1, the insulation holding member 3 can be easily removed from the heat radiation fin 6 by cutting the expansion / contraction head 4a of the support rod 4 with a nipper or the like. The semiconductor device 1 can be removed from the recess 3 a of the insulating holding member 3.

FIG. 3 is a sectional view of an essential part of a second embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same parts, 13 is an insulating holding member, 13a is a concave portion for accommodating the semiconductor device 1, and 14 is a concave portion.
Is a support rod, 14a and 14c are expansion / contraction heads, and 14b and 14d.
Is a split groove. In this embodiment, the insulation holding member 1
3 and the support rod 14 are formed as separate bodies, and the support rod 14 is replaceable.

That is, the support rod 14 has split grooves 14b,
14d has expansion / contraction heads 14a, 14c,
The supporting rod 14 is penetrated through the insertion hole formed in the concave portion 13a of the insulating holding member 13, the leaf spring 5 is arranged in the concave portion 13a, and the supporting rod 14 is penetrated through the mounting hole 1a of the semiconductor device 1. Radiating fins 6 through the thermal sheet 7
When the insertion hole 6a of the support rod 14 is penetrated, the insulating holding member 13 and the heat radiation fin 6 are coupled by the expansion / contraction heads 14a and 14c at both ends of the support rod 14, and the semiconductor device 1 by the leaf spring 5.
The semiconductor device 1 can be attached to the heat radiation fin 6 by pressing the heat radiation fin 6 to the heat radiation fin 6 in the same manner as in the embodiment shown in FIG.

Since the supporting rod 14 can be pulled out by cutting one of the expansion / contraction heads of the supporting rod 14, the insulating holding member 13 is removed from the heat radiation fin 6, and the insulating holding member 13 is removed. The semiconductor device 1 can be removed. Then, the new support bar 14 can be inserted into the insertion hole formed in the insulating holding member 13, the new semiconductor device 1 can be housed in the recess 13 a, and attached to the heat radiation fin 6.

FIG. 4 is a sectional view of an essential part of a third embodiment of the present invention, in which the same reference numerals as in FIG. 1 indicate the same parts, 16 is a radiation fin, 16a is an insertion hole, 22 is a screw, and 23 is an insulation. A holding member, a concave portion 23a, an extension portion 23f, and a support rod 24.

In this embodiment, the insulating holding member 23 is formed with an extension portion 23f for attaching to the upper portion of the heat radiation fin 16, and the support rod 24 formed so as to project into the recess 23a of the insulating holding member 23 is Support rod 4 in the above-mentioned embodiment
The length is shorter and the expansion / contraction head 4a is not formed. The recess 23a of the insulation holding member 23 has the same structure as the recesses 3a and 13a of the insulation holding members 3 and 13 of the above-described embodiments.

The leaf spring 5 is provided in the recess 23a of the insulating holding member 23.
Is arranged, the supporting rod 24 is pierced through the mounting hole 1a of the semiconductor device 1 to support the semiconductor device 1 in the recess 23a, and the tip portion of the supporting rod 24 protruding from the mounting hole 1a of the semiconductor device 1 is attached to the thermal sheet. 7 insertion hole and radiating fin 1
6 is inserted into the insertion hole 16a of the insulating holding member 23, the extension 23f of the insulating holding member 23 is placed on the upper portion of the heat radiation fin 16 and attached by the screw 22, the semiconductor device 1 radiates heat through the thermal sheet 7 by the leaf spring 5. It is pressed against the fin 16. Then, the leads 2 of the semiconductor device 1 are inserted into the through holes of the printed circuit board 8 and the heat radiation fins 16 are fixed to the printed circuit board 8 with the screws 9.

FIG. 5 is a schematic perspective view of the semiconductor device.
(A) shows a schematic perspective view of the TO-3P type, and (b) shows a schematic perspective view of the TO-220 type. The lead 2 is led out from one end of a substantially flat mold case, and the mounting hole 1a is basically the same. However, the specific shape and dimensions differ slightly depending on the manufacturer. The mounting hole 1a has a diameter of about 3 to 5 mm, and the support rods 4, 14, 24 are formed to have a diameter that allows the mounting hole 1a to penetrate therethrough.

Further, in the recesses 3a, 13a and 23a of the above-mentioned insulation holding members 3, 13 and 23, TO-3 shown in FIG.
Not only the P-type semiconductor device but also the TO-22 shown in (b)
A 0-type semiconductor device can be housed and attached to the radiation fin.

FIG. 6 is a sectional view of the essential portions of the fourth embodiment of the present invention, in which the same symbols as in FIG. 4 indicate the same parts, and the semiconductor device 1 is a TO-220 type shown in FIG. 5 (b). Shows the case. That is, the mounting hole 1a is formed in the thin portion of the mold case.
The support rod 24 is inserted into the extension holding portion 23 of the insulation holding member 23.
When f is attached to the upper portion of the radiation fin 16 with the screw 22, the thick portion of the mold case of the semiconductor device 1 can be pressed by the leaf spring 5 to be attached to the radiation fin 16 via the thermal sheet 7. . That is, as described above, the present invention can be applied to any type of semiconductor device of TO-3P type and TO-220 type.

FIG. 7 is a sectional view of the essential parts of the fifth embodiment of the present invention, in which 1 is a semiconductor device, 1a is a mounting hole, 2 is a lead, 5 is a leaf spring, 8 is a printed circuit board, and 9 and 32 are. screw,
33 is an insulating holding member, 33a is a concave portion, 33f is an extension portion,
Reference numeral 34 is a support rod, 36 is a radiation fin, and 37 is a thermal sheet.

In this embodiment, as compared with the support rod 24 in the embodiment shown in FIG. 4 or 6, the length of the support rod 34 formed so as to project from the recess 33a of the insulating holding member 33 is shortened, When the extension portion 33f of the insulation holding member 33 is fixed to the upper portion of the heat radiation fin 36 with the screw 32 and the semiconductor device 1 is attached to the heat radiation fin 36 via the thermal sheet 37, the support rod is inserted from the attachment hole 1a of the semiconductor device 1. 34 does not project, so that the thermal sheet 37 and the radiation fin 36 do not need to have insertion holes.

In this case, a case is shown in which a split groove is formed at the tip so that the semiconductor device 1 housed in the concave portion 33a of the insulating holding member 33 does not fall out due to the short support rod 34. It is also possible to form fine irregularities on the outer periphery of the support rod 34 so that the semiconductor device 1 does not fall off when it is inserted into the mounting hole 1a of the semiconductor device 1.

[0030]

As described above, according to the present invention, the concave portions 3a, 13a, 23 of the insulating holding members 3, 13, 23, 33 are formed.
The leaf springs 5 are disposed on the a and 33a, the semiconductor device 1 is accommodated therein, and the heat radiation fins 6, 16 and 36 are provided with the insulation holding members 3, 3.
By mounting 13, 23 and 33, the semiconductor device 1 can be pressed against the radiating fin 5 side by the leaf spring 5, so that the mounting of the semiconductor device 1 is extremely easy even in a narrow place as compared with the conventional example. There is an advantage to be.

Further, the partition walls between the concave portions of the insulating holding member can make the arrangement interval of the semiconductor device 1 narrower than that of the conventional example, and there is an advantage that the device can be downsized. Further, the semiconductor device 1 can be positioned by the support rod, and when the expansion / contraction head is formed, the semiconductor device 1 can be easily assembled by pushing, and the expansion / reduction head is cut, so that the semiconductor device 1 is It can be easily removed. When the support rod 14 is separate from the insulation holding member 13, the insulation holding member 13 can be used repeatedly. When the length of the support rod 34 is shortened,
There is an advantage that it is not necessary to form an insertion hole in the thermal sheet 37 and the radiation fin 36.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a first embodiment of the present invention.

FIG. 2 is a perspective view of an insulation holding member according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of essential parts of a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of an essential part of a third embodiment of the present invention.

FIG. 5 is a schematic perspective view of a semiconductor device.

FIG. 6 is a cross-sectional view of essential parts of a fourth embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts of a fifth embodiment of the present invention.

FIG. 8 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1 Semiconductor Device 1a Mounting Hole 2 Lead 3 Insulation Holding Member 3a Recess 4 Support Rod 4a Expansion / Reduction Head 5 Leaf Spring 6 Radiating Fin 6a Insertion Hole 7 Thermal Sheet 8 Printed Circuit Board

Claims (5)

[Claims] 1. A mounting structure of a semiconductor device, wherein a lead is led out from one end of a substantially flat mold case having a mounting hole, and a semiconductor device mounting structure for mounting the semiconductor device on a radiation fin. A holding member; a leaf spring arranged in the recess of the insulation holding member for pressing the semiconductor device against the heat radiation fin when the insulation holding member is mounted on the heat radiation fin; A mounting structure for a semiconductor device, comprising: a support rod that projects into the recess and is inserted into the mounting hole of the semiconductor device to support the semiconductor device. 2. The expansion and contraction of the support rod projecting from the recess of the insulation holding member and penetrating an insertion hole formed in the heat dissipation fin when the insulation holding member is pressed against the heat dissipation fin to prevent the support rod from coming off. 2. The mounting structure for a semiconductor device according to claim 1, wherein the head has a tip. 3. The expansion / contraction of the support rod, which penetrates the insertion hole formed in the insulation holding member, the attachment hole of the semiconductor device, and the insertion hole formed in the heat dissipation fin, and which prevents the support rod from coming off. 2. The mounting structure for a semiconductor device according to claim 1, further comprising heads at both ends. 4. A mounting structure of a semiconductor device, wherein a semiconductor device having leads extending from one end of a substantially flat mold case having a mounting hole is mounted on a radiation fin, wherein a recess for accommodating the semiconductor device and the heat radiation are provided. An insulating holding member having an extension attached to the fin and an insulating holding member disposed in the recess of the insulating holding member. When the extension of the insulating holding member is attached to the heat radiation fin, the semiconductor device serves as the heat radiation fin. A semiconductor device comprising: a leaf spring for pressing; and a support rod that projects into the recess of the insulating holding member and is inserted into the mounting hole of the semiconductor device to support the semiconductor device. Mounting structure. 5. The length of the support rod protruding from the recess of the insulation holding member and not protruding from the mounting hole of the semiconductor device when the extension of the insulation holding member is mounted on the heat radiation fin. The mounting structure for a semiconductor device according to claim 4, wherein: