JPH08288441A - Power semiconductor device - Google Patents

Abstract

PURPOSE: To eliminate the need of a complicated manufacturing process so as to reduce the manufacturing cost and size of a power semiconductor device by integrally forming an insulating circuit board and frame-like case of the same resin and forming a circuit pattern of a metallic plate on the circuit board. CONSTITUTION: A frame-like case 5 which becomes the side wall of a liquid sealing resin housing section and insulating circuit board 6 which becomes the bottom of the housing section are integrally molded of the same resin. In the circuit board 6, an input-side circuit pattern 1 and output-side circuit pattern 2 are formed. An external output terminal 4 integrally formed with the circuit pattern 2 is bent at an angle of about 90 deg. against the pattern 2 and led out of the case 5 after passing through the case 5. The patterns 1 and 2 and terminal 4 are made of brass, etc., plated with tin, etc. Therefore, the manufacturing cost of a power semiconductor device can be reduced, because no complicated process is required at the time of joining the case 6 to the board 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mounts various electronic components including a semiconductor element and external input / output terminals on an insulating circuit board, and has a frame-like case surrounding the insulating circuit board. The present invention relates to a power semiconductor device such as, for example, a solid state relay (hereinafter referred to as “SSR”) module which is molded with a sealing resin to have a module having a predetermined function.

[0002]

2. Description of the Related Art An example of the structure of a conventional power semiconductor device is
This will be described with reference to FIG. In addition, FIG.
It is a schematic diagram showing a manufacturing process of a conventional power semiconductor device.

First, an insulating layer 21 is formed on the entire surface of a metal plate 20 made of Al or the like, and an insulating circuit board 6 made of a metal base on which circuit patterns 1 and 2 are formed by conductors. The cream-like solder 11 is applied to the electronic component mounting region including the semiconductor element, the semiconductor element 7 and the electric components 8 and 10 are placed at predetermined positions, and the entire metal-based insulating circuit board 6 is heated and cooled. As a result, the creamy solder 11 is melted and hardened, and the semiconductor element 7 and the electric components 8 and 10 are soldered.
(A), (b)>.

Next, cream-like solder 11 'is applied to the external input / output terminal 3, 4 mounting areas of the circuit patterns 1 and 2 on the metal-based insulating circuit board 6, and the cream-like solder 1 is applied.
After setting the external input / output terminals 3 and 4 to the portion to which 1'is applied by a jig or the like, the creamy solder 11 'is melted and hardened by heating and cooling the entire metal base insulating circuit board 6, The input / output terminals 3 and 4 are soldered and electrically connected <Fig. 6 (c)>.

After that, the frame-shaped case 5 to be the wall surface is fixed to the outer peripheral portion of the metal-based insulating circuit board 6 by using an adhesive 22 such as silicon or epoxy-based resin (FIG. 6D).
>. Finally, in order to shield and seal the inside of the frame-like case 5 from the outside to enhance reliability, a liquid sealing resin 12 made of epoxy resin or the like is injected and cured to complete the power semiconductor device <FIG. e)>.

As described above, the manufacturing process of the conventional power semiconductor device is roughly divided, and as shown in the assembly flow chart of FIG. 5A, the electronic component including the semiconductor element is soldered to the metal base insulating circuit board. Component mounting process,
I / O terminal fixing process of soldering external I / O terminals to the metal-based insulating circuit board, and attaching a frame-shaped case to the metal-based insulating circuit board on which electronic components including semiconductor elements and external I / O terminals are mounted 4 of the frame fixing step and the insulating resin injecting step of injecting and curing the sealing resin inside the frame-shaped case
Consists of steps.

[0007]

In the conventional power semiconductor device, when the liquid sealing resin is injected and cured, the frame-shaped case is used to form the wall surface of the liquid resin housing portion. The outer frame fixing process for adhering to the metal base insulating circuit board, which is the bottom of the board, and the external input to fix the external input / output terminals to the circuit pattern on the metal base insulating circuit board almost perpendicularly An output terminal fixing process is required.

In the step of fixing the outer frame, a resin such as silicone or epoxy is used as an adhesive, but the bonding work using these takes a relatively long time, and when a thermosetting adhesive is used. Requires a facility such as a thermostatic oven for heating and curing the adhesive, which increases the manufacturing cost.

In the step of fixing the external input / output terminal, the external input / output terminal and the circuit pattern on the metal base insulating circuit board are electrically connected and fixed through the solder material, and this work also takes a relatively long time. In addition, a jig or the like for vertically fixing the external input / output terminal to a desired position is required, which increases the manufacturing cost.

Further, when the power semiconductor device becomes high in temperature due to heat generation of the power semiconductor device itself, increase in ambient temperature, etc., the external input / output terminal and the circuit are affected by the difference in expansion coefficient between the external input / output terminal and the sealing resin. Stress is applied to the solder material that is the joint with the pattern, and cracks may occur in the solder material, which has been a problem of reliability.

Further, a region for soldering the external input / output terminals to the circuit pattern is required, which hinders the miniaturization of the metal-based insulating circuit board.

The present invention has been made in view of the above problems, and provides a power semiconductor device which is cheaper, more reliable, and smaller in size than conventional products.

[0013]

To achieve the above object, a power semiconductor device of the present invention comprises an insulating circuit board having a circuit pattern made of a metal plate embedded therein, and a peripheral portion of the insulating circuit board. An electronic component including a frame-like case that is integrally erected upright with the same material and serves as a side wall of the encapsulating resin housing portion, and a semiconductor element electrically connected to the circuit pattern embedded inside the insulating circuit board, and External input / output terminals,
It is characterized in that it is provided with a sealing resin which is injected and cured in a recess formed by the insulating circuit board and the frame-shaped case.

Further, in the power semiconductor device according to the present invention, the external input / output terminal is formed integrally with the circuit pattern embedded in the insulating circuit board, and is bent at an angle of approximately 90 degrees with respect to the circuit pattern. Through the frame-shaped case,
It is characterized in that it is led out of the frame-shaped case.

[0015]

With the above structure, according to the power semiconductor device of the present invention, the insulating circuit board and the frame-like case are integrally molded with the same resin, and the circuit pattern is formed inside the insulating circuit board by the metal plate. Since the structure is formed, a complicated step of fixing the frame-shaped case to the insulating circuit board is not necessary. In addition, it becomes possible to form a circuit pattern directly under a mounting area for electronic components and the like, which increases the degree of freedom in designing the circuit pattern.

According to the power semiconductor device of the second aspect,
Since the external I / O terminals are formed integrally with the circuit pattern and pass through the inside of the frame-shaped case and are led out to the outside of the frame-shaped case, the step of soldering the external I / O terminals to the circuit pattern is unnecessary, and Since there is no joint between the output terminal and the circuit pattern by the solder material, the problem of cracking in the joint due to thermal stress or the like is solved.

Further, since the area for soldering the external input / output terminal to the circuit pattern is unnecessary, the insulating circuit board can be downsized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A power semiconductor device according to the present invention is formed by an insulating circuit board and a frame-like case by surrounding an insulating circuit board on which electronic components including semiconductor elements and external input / output terminals are mounted with a frame-like case. In a structure in which a liquid resin is injected into the recessed portion and cured, the insulating circuit board and the frame-shaped case are integrally molded with the same resin, and the circuit pattern is embedded inside the insulating circuit board and led out to the outside. The external input / output terminals that pass through the frame-shaped case are integrally formed with the circuit pattern inside the insulating circuit board.

The structure of the power semiconductor device of the present invention will be described below.
As an example, a so-called 5-channel power SSR module in which five SSRs are connected in parallel will be described in detail with reference to the drawings.

In the embodiment, the same functional parts as those of the conventional example are designated by the same symbols.

1A and 1B are structural views of an insulating circuit board integrated with a frame-like case according to the present invention. FIG. 1A is an internal perspective view from the upper surface side, and FIG. 1B is a front view including a partial cross section. c) is a side sectional view.

As shown in FIG. 1, a frame-shaped case 5 which serves as a side wall of the liquid sealing resin accommodating portion and an insulating circuit board 6 at the bottom are integrally formed of the same resin.

The frame-shaped case 5 integrally formed
As the material of the insulating circuit board 6, a thermoplastic resin having a heat distortion temperature of 230 ° C. or higher, such as polyphenylene sulfide (PPS), is used in order to withstand heating during soldering in a later step.

The input side circuit pattern 1 and the output side circuit pattern 2 formed in a desired circuit are the insulating circuit board 6
Is formed inside.

The external output terminal 4 is formed integrally with the output side circuit pattern 2, is bent at an angle of approximately 90 degrees with respect to the output side circuit pattern 2, passes through the inside of the frame-shaped case 5, It is led to the outside of the case 5.

Although only the external output terminal 4 is formed integrally with the output side circuit pattern 2 in this example, the external input terminal may be formed integrally with the input side circuit pattern 1. As a material for the circuit patterns 1 and 2 and the external input / output terminals 3 and 4, a brass plate or the like having a thickness of about 0.3 to 0.5 mm is used, and tin plating or the like is applied if necessary.

Reference numeral 13 is a through hole for fixing a screw when it is attached to an external device.

FIG. 2 is an external view of the frame-shaped case-integrated insulative circuit board from the top side.

As shown in FIG. 2, a window portion 14 is provided on the insulating circuit board 6 at the soldered portion of the electronic component including the semiconductor element of the input side circuit pattern and the output side circuit pattern,
Part of the circuit pattern is exposed.

3A and 3B are structural views in which electronic parts including semiconductor elements are mounted, FIG. 3A is a plan view, FIG. 3B is a front view including a partial cross section, and FIG.

As shown in FIG. 3, an input resistor 10 for adjusting an input current, an SSR element 7 composed of a semiconductor element, a capacitor 8 and a resistor 9 constituting a snubber circuit for protecting the SSR element 7 from external noise are predetermined. Soldered to the position.

These semiconductor element 7 and electronic component 8,
9 and 10 are of lead terminal type, and the lead terminal 15 is inserted into a through hole 16 formed in a circuit pattern exposed from the surface of the insulating circuit board 6 so that the lead terminal 15 and the circuit pattern are soldered. Soldered by material. As the solder material, for example, a creamy melting point 1
Sn / Pb eutectic solder at 83 ° C is used.

Reference numeral 17 is an external input connector. Like the external output terminal 4, the external input connector 17 may be an external input terminal that is integrally formed with the input side circuit pattern 1 and passes through the inside of the frame-shaped case 5 and is led out from the frame-shaped case 5 to the outside.

Next, a method of manufacturing a power semiconductor device according to an embodiment of the present invention will be described with reference to the schematic diagrams shown in FIGS.

First, the external input / output terminals 3 and 4 integrally formed with the input side circuit pattern 1, the output side circuit pattern 2 and the circuit patterns 1 and 2 which are made of a metal plate having a thickness of about 0.3 to 0.5 mm. Is placed at a predetermined position in a mold (not shown), and the frame-shaped case 5 and the insulating circuit board 6 at the bottom are integrally molded by the same resin by so-called insert molding, thereby forming a frame-shaped case integrated type. The insulating circuit board 23 is completed <FIG. 4 (a)>.

Next, an electronic component 8 including the semiconductor element 7,
9 and 10 are circuit patterns 1 and 2 inside the insulating circuit board 6.
Solder with the solder material 11. This solder material 11
Is, for example, Sn / having a cream-like melting point of 183 ° C.
Pb eutectic solder is used <Fig. 4 (b)>.

Finally, the liquid sealing resin 1 is placed in the recess surrounded by the insulating circuit board 6 and the frame-shaped case 5 which are made of the same resin.
2 is injected and cured to complete the power semiconductor device.

Here, as the liquid sealing resin 12, for example, a thermosetting epoxy resin is used <FIG. 4 (c).
>.

According to the power semiconductor device of the present invention configured as described above, as shown in a comparison diagram of the assembly flowchart of the conventional power semiconductor device of the present invention shown in FIG. The external input / output terminal fixing step of soldering the external input / output terminal to the circuit pattern and the outer frame fixing step of adhering the frame-shaped case to the insulating circuit board, which are required in the above step, are unnecessary, and the steps can be simplified.

[0040]

As is apparent from the above description, according to the power semiconductor device of the first aspect of the present invention, the insulating circuit board and the frame-shaped case are integrally molded with the same resin, and the inside of the insulating circuit board is formed. Since the circuit pattern is formed on the metal plate, the complicated process of adhering the frame-shaped case to the insulative circuit board is unnecessary, and the manufacturing cost can be reduced.

Furthermore, it becomes possible to form a circuit pattern directly under the mounting area for electronic parts and the like, and the degree of freedom in designing the circuit pattern increases.

According to the power semiconductor device of the second aspect,
Since the external input / output terminals are formed integrally with the circuit pattern and pass through the inside of the frame-shaped case and are led out to the outside, the process of soldering the external input / output terminals to the circuit pattern is unnecessary, and the manufacturing cost can be reduced. Become.

Further, since there is no joint between the external input / output terminal and the circuit pattern by the solder material, the problem of cracks occurring at the joint due to thermal stress is solved.
A highly reliable power semiconductor device can be provided.

Further, since the area for soldering the external input / output terminal to the circuit pattern is unnecessary, the power semiconductor device can be downsized.

[Brief description of drawings]

1A and 1B are structural views of a frame-shaped case-integrated insulating circuit board of the present invention, in which FIG. 1A is an internal perspective view from the upper surface side, and FIG.
Is a front view including a partial cross section, and (c) is a side cross-sectional view.

FIG. 2 is an external view of the frame-shaped case-integrated insulative circuit board of the present invention seen from the upper surface side.

FIG. 3 is a structural diagram in which electronic components and the like are mounted on a frame-shaped case-integrated insulating circuit board of the present invention, (a) is a plan view,
(B) is a front view including a partial cross section, and (c) is a side cross-sectional view.

4A to 4C are schematic views showing a manufacturing process of the power semiconductor device of the present invention.

FIG. 5 is a comparison diagram of assembly flowcharts of a conventional power semiconductor device and the present invention.

6A to 6E are schematic views showing a manufacturing process of a conventional power semiconductor device.

[Explanation of symbols]

 1 Input side circuit pattern 2 Output side circuit pattern 3,4 External input / output terminal 5 Frame case 6 Insulating circuit board 7 Semiconductor element 8, 9, 10 Electronic parts

Claims (2)

[Claims] 1. An insulating circuit board in which a circuit pattern made of a metal plate is embedded, and an insulating circuit board and a side wall of a sealing resin accommodating portion, which are integrally erected from the peripheral portion of the insulating circuit board with the same material. A frame-shaped case, an electronic component and an external input / output terminal including a semiconductor element electrically connected to the circuit pattern embedded in the insulating circuit board, the insulating circuit board and the frame-shaped case A power semiconductor device, comprising: a sealing resin that is injected into the recess formed by and cured. 2. The external input / output terminal is integrally formed with the circuit pattern embedded in the insulating circuit board, and is bent at an angle of about 90 degrees with respect to the circuit pattern,
The power semiconductor device according to claim 1, wherein the power semiconductor device passes through the inside of the frame-shaped case and is led out to the outside of the frame-shaped case.