JPH09139448A - Semiconductor fitting, its mounting method and semiconductor device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for easily mounting and dismounting a semiconductor device, with a mounting board having a high mounting density. SOLUTION: A fitting 10 for mounting a semiconductor 20 on a mounting board 30 includes a pedestal 11 for accommodating the semiconductor 20 as orientated upside down, leg parts 12 for carrying the pedestal 11 to be fixed to the mounting board 30, and a holding part 13 holding a mounting part 20a of the semiconductor 20, which parts are integrally formed. The pedestal 11 is integrally formed with a heat radiating fin 15, and is provided with a projection 15 which fits in a threaded hole 22 for mounting of the semiconductor 20 at a position biased nearly from the center of the fin 15 toward the holding part 13. When the leg parts 12 of the mounting fitting 10 are soldered to the mounting board 30, a predetermined spacing is secured between a rear face of the pedestal 11 and a mounting face of the mounting board 30, thus attaining formation of a wiring pattern even on the mounting board on the underside of the semiconductor 20. The semiconductor 20 can be easily dismounted from the pedestal 11 only by removing solder at leads.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting device for mounting a semiconductor on a mounting substrate, for example, a mounting device for a so-called discrete semiconductor such as a general-purpose transistor.

[0002]

2. Description of the Related Art In the conventional electronic device manufacturing technology,
When mounting a discrete type semiconductor such as a general-purpose transistor on a mounting substrate such as a printed circuit board, there is a condition (height limitation) that the semiconductor is mounted within a predetermined height on the substrate. In order to meet this height limitation, conventionally, a mounting structure in which a semiconductor is laid down sideways and fixed with a screw (FIG. 11) and a mounting structure in which the semiconductor body is laid down sideways and the semiconductor body is fixed to a mounting substrate with an adhesive are adopted. It was

Specifically, in the mounting structure using screws (FIG. 11), the mounting substrate 90 has through holes 91 and 92 for mounting.
Is provided at a predetermined mounting position, and the mounting portion 8 of the semiconductor 80 is
0a and the mounting screw hole 82 and the through hole 9 described above.
1 and align them with screws 71 and nuts 72
Fixed by. At this time, the lead 81 of the semiconductor 80 is bent at a substantially right angle to the surface of the mounting board 90, and the tip portion 81 a of the lead 81 is penetrated into the through hole 92 of the mounting board 90.
And then brazed with solder. The semiconductor is entirely attached to the substrate by fixing the mounting portion 80a of the semiconductor 80 with the screw 71 and fixing the leads 81, 81 ... By soldering.

On the other hand, in the mounting structure using an adhesive (FIG. 12), the semiconductor 80 is laid sideways and the back surface 80b of the main body is kept.
Are surface-bonded to the mounting substrate 90 by the adhesive 73.
Further, the lead 81 is bent perpendicularly to the surface of the mounting substrate 90, and the tip portion 81a thereof is inserted into the through hole 92 and brazed by soldering. Also in this case, the leads 8 are fixed by fixing the back surface 80b with the adhesive 73 and soldering.
The semiconductor was attached to the mounting substrate 90 by fixing 1, 81 ...

[0005]

However, in the field of manufacturing electronic equipment in recent years, not only is there a demand for downsizing of equipment and high-density mounting on a mounting substrate, but also easy removal of electronic parts such as semiconductors. Came to be requested. This is for the replacement of parts for improvement or the replacement of defective parts, and for the recycling of various parts constituting the electronic device.

However, in the conventional mounting structure described above, the former cannot mount another electronic component on the back surface of the mounting board because the mounting screws and the leads project to the back side of the mounting board. It cannot meet the high-density mounting method of double-sided mounting. On the other hand, in the latter, since only the lead portion protrudes to the back surface, the mounting efficiency is higher than the mounting structure by screwing, but the strength of fixing the semiconductor is lower than that by the mounting structure by screwing, and Since the mold part on the back surface of the semiconductor is adhered over the entire surface with an adhesive, it is difficult to remove it and it is not suitable for replacing parts.

The present invention has been made in view of the above circumstances, and in the case where there is a height limit when mounting a semiconductor on a mounting substrate, the semiconductor can be mounted at a high density, and It is an object of the present invention to provide a semiconductor fixture that can be easily attached / removed, a method of attaching the same, and a semiconductor device using the same.

[0008]

According to a first aspect of the present invention, there is provided a mounting part for mounting a semiconductor on a mounting board, a pedestal part for storing the semiconductor in an inverted manner, a plurality of legs fixed to the mounting board, and The semiconductor device is configured so as to be integrally formed with a sandwiching portion that sandwiches the semiconductor mounting portion housed in the pedestal portion.

According to a second aspect of the present invention, the radiating fins are integrally formed on the pedestal portion of the fixture. According to a third aspect of the present invention, a convex portion that locks a mounting screw hole formed in the semiconductor is provided at a position substantially in the center of the pedestal portion of the fixture from the sandwiching portion. According to a fourth aspect of the present invention, openings are provided at the attachment positions of the legs of the pedestal of the fixture.

According to a fifth aspect of the present invention, a step is provided on the bottom surface of the leg portion of the fixture for ensuring a predetermined gap between the back surface of the pedestal portion and the attachment surface of the mounting board. According to a sixth aspect of the present invention, when mounting the mounting tool to the mounting board, the leg portion and the mounting hole of the mounting board are positioned, and a gap of a predetermined distance is provided between the back surface of the pedestal portion and the mounting surface of the mounting board. With the above-mentioned condition secured, the leg portion is fitted into the mounting hole and brazed.

According to a seventh aspect of the present invention, a semiconductor device is constituted by the mounting member according to any one of the first to fifth aspects, a mounting board, and a semiconductor, and the leg portions of the mounting tool are mounted on the mounting board. , The semiconductor mounting portion is sandwiched between the sandwiching portions and housed in the pedestal portion, and the semiconductor leads are brazed to the electrodes of the mounting board by soldering. According to the invention of claim 8, when a semiconductor having a mounting screw hole is placed upside down on a mounting board and the mounting board is fixed to the mounting board, a protrusion is provided in advance on the mounting tool, and the protrusion is used as a mounting screw hole for the semiconductor. The mounting tool is fixed to the mounting board in the inserted state and while covering the semiconductor body from the upper surface with the mounting tool.

(Operation) In the invention of claim 1, when the semiconductor is housed in the pedestal portion of the fixture, a spring action occurs in the holding portion, and the semiconductor is pressed against the pedestal portion. In this case, it is not necessary to fix the semiconductor directly to the mounting board.

According to the second aspect of the present invention, the heat radiation fins provided on the pedestal can efficiently dissipate the heat generated from the semiconductor housed in the pedestal. According to the third aspect of the invention, at the time of mounting, the mounting screw hole formed in the semiconductor can be fitted with the convex portion at the substantially center of the pedestal portion for positioning.

According to the invention of claim 4, by the action of the opening provided at the mounting position of the leg portion of the pedestal portion, the heat required for the work is unnecessary when brazing the leg portion to the mounting board. Diffusion is prevented. In the invention of claim 5,
The step formed on the bottom surface of the leg portion facilitates the work of securing a gap between the back surface of the pedestal portion and the mounting substrate.

According to the sixth aspect of the present invention, since a gap having a predetermined distance is secured between the back surface of the pedestal portion and the mounting surface of the mounting board, it is possible to effectively use the wiring board by forming another wiring pattern on the mounting board. Planned. In the invention of claim 7, the semiconductor mounting portion is fixed to the pedestal portion only by sandwiching the semiconductor mounting portion in the sandwiching portion of the mounting fixture, and the lead can be mounted by simply brazing the lead to the electrode of the mounting substrate. Further, the semiconductor can be removed only by removing the solder of the lead and removing the semiconductor from the holding portion.

According to the invention of claim 8, the protrusion of the fixture is inserted into the screw hole for attachment of the semiconductor, so that the positioning thereof is easy and the semiconductor can be firmly fixed to the mounting substrate.

[0017]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

(First Embodiment) FIGS. 1 to 7 show a first embodiment (corresponding to claims 1 to 7) of the present invention. The semiconductor 20 attached to the mounting substrate 30 in this embodiment is a general-purpose transistor and is molded with resin. This transistor is of a type that consumes relatively little power, and its body portion is not provided with a radiation fin. A mounting screw hole 22 is provided substantially in the center of the mounting portion 20a of the semiconductor 20.

First, an outline of a semiconductor device having the mounting structure of the first embodiment will be described. As shown in FIGS. 1 and 2, the mounting board 30 is provided with a mounting bracket (mounting tool) 10.
For example, the semiconductor 20 is brazed by solder, and the semiconductor 20 is installed on the pedestal portion 11 of the mounting bracket 10. Then, one end of the mounting portion 20a of the semiconductor 20 is sandwiched by the sandwiching portion 13 of the mounting bracket 10, and its back surface 20 is supported by its spring action.
The b is fixed in a state of being in contact with the pedestal portion 11.

The pedestal portion 11 is provided with a protrusion (tab) 14 as will be described later, and the protrusion 14 is attached at the time of mounting.
However, the semiconductor 20 is fitted on the mounting screw hole 22 of the semiconductor 20, and the semiconductor 20 is positioned on the mounting bracket 10. on the other hand,
The leads 21, 21 ... Of the semiconductor 20 are bent in a gentle crank shape, and the tip portions 21a, 21a ... Are brazed to the electrodes 31, 31.

Then, the semiconductor 2 by the mounting bracket 10 is used.
The semiconductor 20 as a whole is mounted on the mounting substrate 30 by fixing 0 and brazing the leads 21, 21 ..., Thus, a semiconductor device is configured. Next, the shape of the mounting bracket 10 and the function of each part constituting the mounting bracket 10 will be described.

As shown in FIGS. 3 and 4, the mounting bracket 10
Is a metal fitting integrally formed in a substantially chair shape, and is a pedestal part 1
1 to 4, four leg portions 12, 12, ..., A sandwiching portion 13, a side portion of which has a substantially U-shaped cross section, a protrusion 14, and a radiation fin 15. In addition, openings 11a, 11a ... Are formed in the mounting portions of the legs 12, 12, ... The openings 11a, 11a, ... Generate heat required for soldering the legs 12, 12, ...
1) Further, the heat radiation fins 15 prevent the heat from being released to the outside.

Further, a projection (positioning projection) 14 formed at a position closer to the sandwiching portion 12 in the center of the pedestal portion 11
Is for locking the mounting screw hole 22 formed in the semiconductor 20 when the semiconductor 20 is stored, and for positioning the semiconductor screw. The mounting of the semiconductor 20 using the mounting bracket 10 is performed as follows. First, the leg portions 12, 12 ... Are inserted into the through holes 32, 32 ... Of the mounting board 30 and brazing by soldering is performed (see FIG. 5).

A round shape is formed in the through holes 32, 32 ... With a thin copper layer, so that other electronic components installed on the back surface of the mounting board 30 are electrically connected to the semiconductor 20. Is possible. By the way, this first
In the embodiment of FIG.
When fixing to ..., the following two points are considered.

First, the legs 12, 12 ... Are mounted on the mounting substrate 30.
That is, the back side 30b does not project. This is because, when the other electronic components are attached to the back surface side 30b, if the legs 12, 12, ... Project, the mounting on the back surface side is restricted, and the mounting efficiency is reduced. Second, the pedestal 1
That is, a gap S having a predetermined interval is provided between the back surface 11b of the first substrate 1 and the front surface 30a of the mounting substrate 30 (see FIG. 2).

By providing the gap S in this way,
The wiring pattern can be formed on the mounting board (printed circuit board) below the mounting position of the semiconductor 20 where the conventional wiring pattern could not be formed. The mounting board 30
The method of attaching the semiconductor 20 to the attachment metal fitting 10 fixed to is carried out as follows.

When mounting the semiconductor 20 on the mounting member 10, the mounting portion 20a of the semiconductor 20 is sandwiched by the sandwiching portion 13 of the mounting member 10 (FIG. 6), and then rotated in the direction indicated by arrow A in the figure. To do. At this time, the lower surface 20b of the semiconductor is fixed in contact with the pedestal portion 11 of the mounting member 10 by the spring action of the holding portion 13. At this time, the pedestal 11
Since the protrusion (tab) 14 formed on the fitting portion is fitted into the mounting screw hole 22 formed on the mounting portion 20a, the positioning can be easily performed (see FIG. 2).

On the other hand, the leads 21, 21, ... Of the semiconductor 20.
Is bent into a gentle crank shape as described above,
The tips 21a, 21a ... Are the electrodes 3 on the mounting substrate 30.
, 31 ... Are brazed by solder (see FIG. 1). Semiconductor 20 mounted in this way
, The solder adhered to the tip portions 21a, 21a ... Of the leads 21, 21 ... Is melted and removed, and thereafter, the mechanical action is exerted against the spring action of the holding section 13. It can be removed by simply uncoupling it.

When the mounting bracket 10 is mounted on the mounting substrate 30, the back surface 11 of the pedestal 11 is mounted as described above.
It is necessary to provide a gap S between the b and the front surface 30a of the mounting board 30 and prevent the leg portions 12 thereof from projecting to the back surface of the mounting board 30. The leg 12 of the metal fitting 10 may be provided with a step having a height h2 in advance as shown in FIG.

The width w of the leg 12 is determined by the through hole 32.
The size is determined according to the inner diameter of the round provided in. Further, the height h2 is set to be equal to or less than the thickness of the mounting board 30 so that the leg portion 12 does not project to the back surface side of the mounting board 30. Further, the height h1 of the leg portion 12 is determined so as to secure the gap S to the extent that the wiring pattern can be effectively formed on the mounting substrate 30 below the semiconductor 20.

Instead of providing the above step, a spacer may be installed between the mounting substrate 30 and the pedestal 11 of the mounting member 10 to secure the gap S. Further, if a semiconductor with relatively high power consumption is to be mounted, the two mounting fins 15A, as shown in FIG.
If the one having 15B is used, the heat radiation effect by the heat radiation fins can be obtained in a limited space.

Such a mounting bracket is particularly effective in the case where an electronic device which does not require a radiation fin at an initial design stage is improved later and a radiation fin is provided on the electronic device. In this case, it is not necessary to change the arrangement of electronic components on the mounting board 30. (Second Embodiment) FIGS. 9 and 10 show a second embodiment (corresponding to claim 8) of the present invention.

In the second embodiment, the mounting metal member 4 is used with the back surface 20b of the discrete type semiconductor 20 such as a general-purpose transistor abutting the front surface 50a of the mounting substrate 50.
0 is used to attach to the surface 50A.
As shown in FIG. 9 and FIG.
With the mounting position of 0 on the mounting substrate 50 being determined and aligned, the protrusion 43 formed on the main body 41 is inserted into the mounting screw hole 22 of the semiconductor 20, and in this state, the leg portion 42 is brazed to the mounting portions 52, 52 of the mounting substrate 50.

On the other hand, the leads 21 of the semiconductor 20 are bent in a gentle crank shape as in the case of the first embodiment, and their tip portions 21a, 21a ... Are mounted on the mounting substrate 50.
Are brazed to the electrodes 51, 51 ...

In the mounting structure of the second embodiment, as compared with the conventional mounting structure (FIGS. 11 and 12), the mounting bracket 40 and its lead 21 do not project to the back surface side of the mounting substrate 50. This is particularly effective when electronic components are individually mounted on both the front and back surfaces of the mounting board.

[0036]

As described above in detail, according to the semiconductor mounting tool of the present invention, a mounting screw is not required, and therefore, a member necessary for mounting the front surface on the back side of the mounting substrate protrudes. In addition, the degree of freedom in mounting other electronic components on the back surface is increased, and the mounting efficiency is improved.

In a semiconductor device using this,
Since the strength of fixing the semiconductor is high and the work for removing the semiconductor is easy, it is easy to collect the semiconductor for replacement by improvement of parts or replacement of defective parts, and for recycling various parts. Further, since the wiring pattern can be formed on the mounting substrate below the semiconductor mounting position, the electronic components can be arranged freely and higher density mounting becomes possible. Further, since it is easy to form the heat radiation fins on the fixture, it is possible to form the heat radiation fins on the semiconductor, without changing the design pattern, for the semiconductor that was originally designed to require no heat radiation fins.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a semiconductor mounting structure by a mounting tool according to claims 1 to 7. FIG.

FIG. 2 is a side view showing a partial cross section showing an example of a semiconductor mounting structure by the mounting tool according to any one of claims 1 to 7.

FIG. 3 is a perspective view showing an example of a mounting bracket (mounting tool) according to claims 1 to 7.

FIG. 4 is a plan view showing an example of a mounting bracket according to claims 1 to 7.

FIG. 5 is a perspective view showing an example of a mounting state of the mounting bracket according to claim 1 to the mounting board.

FIG. 6 is a perspective view showing an example of a mounting state of a semiconductor on a mounting bracket according to claim 1 to claim 7;

FIG. 7 is a perspective view showing an example of a shape of a leg portion of the mounting bracket according to claim 1 to claim 7;

FIG. 8 is a perspective view showing another modified example of the attachment fitting according to claim 1 to claim 7;

FIG. 9 is a perspective view of a semiconductor device for explaining an example of a mounting method according to an eighth aspect.

FIG. 10 is a side view showing an example of a semiconductor device to which the mounting method of claim 8 is applied.

FIG. 11 is a side view showing a conventional semiconductor mounting structure by screwing.

FIG. 12 is a side view showing a conventional semiconductor mounting structure using an adhesive.

[Explanation of symbols]

 10, 40 Mounting bracket (mounting tool) 11 Pedestal part 12 Leg part 13 Clamping part 14 Projection (projection for positioning) 15 Radiating fin 20 Semiconductor 21 Lead 22 Mounting screw hole 30, 50 Mounting board

Claims (8)

[Claims] 1. A pedestal for accommodating a semiconductor in an inverted manner, a plurality of legs fixed to a mounting board, and a clamping part for clamping a semiconductor mounting part accommodated in the pedestal are integrally formed. A semiconductor fixture characterized in that. 2. The semiconductor fixture according to claim 1, wherein a radiation fin is integrally formed on the pedestal portion. 3. A positioning convex portion for locking a mounting screw hole formed in a semiconductor is provided at a position substantially in the center of the pedestal portion from the sandwiching portion. 1
Or the semiconductor fixture according to 2. 4. The semiconductor mounting tool according to claim 1, wherein an opening is provided at a mounting position of the leg portion of the pedestal portion. 5. The bottom surface of the leg portion includes a back surface of the pedestal portion,
5. The semiconductor mounting tool according to claim 1, wherein a step is provided between the mounting surface of the mounting substrate and the mounting surface to ensure a predetermined gap. 6. The leg part of the fixture according to claim 1 and the mounting hole of the mounting board are positioned, and the leg part is brazed in a state of being fitted in the mounting hole. At this time, a mounting method of a mounting tool, characterized in that a gap of a predetermined interval is secured between the back surface of the pedestal portion and the mounting surface of the mounting board. 7. The mounting bracket according to any one of claims 1 to 5, a mounting board, and a semiconductor, wherein the legs of the mounting tool are fixed on the mounting board, and the legs are fixed to the holding section. A semiconductor device, wherein a semiconductor is housed in the pedestal with the mounting portion being sandwiched, and a semiconductor lead is brazed to an electrode of the mounting board by soldering. 8. A semiconductor having mounting screw holes is placed upside down on a mounting substrate, the semiconductor device is covered from above with a mounting fixture, and a protrusion provided on the mounting fixture is inserted into the mounting screw hole of the semiconductor. A method of mounting a semiconductor, characterized in that the mounting fixture and the semiconductor are fixed on a mounting board, and the leads of the semiconductor are brazed to the mounting board by soldering.