JP2972112B2 - Power semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art One example of the structure of a conventional power semiconductor device is as follows.
This will be described with reference to FIG. 6 (a) to 6 (e)
It is the schematic which shows the manufacturing process of the 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 having circuit patterns 1 and 2 formed on the insulating layer 21 by conductors. The creamy solder 11 is applied to the electronic component mounting area including the semiconductor element, and the semiconductor element 7 and the electric components 8 and 10 are mounted at predetermined positions, and the entire metal-based insulating circuit board 6 is heated and cooled. Thereby, the creamy solder 11 is melted and hardened, and the semiconductor element 7 and the electric components 8, 10 are soldered <FIG.
(A), (b)>.

Next, creamy solder 11 ′ is applied to the external input / output terminals 3 and 4 mounting areas of the circuit patterns 1 and 2 on the metal-based insulating circuit board 6, and the creamy solder 1 is applied.
After setting the external input / output terminals 3 and 4 at a location where 1 'has been applied by using a jig or the like, the entirety of the metal-based insulating circuit board 6 is heated and cooled to melt and harden the creamy solder 11'. The input / output terminals 3 and 4 are soldered and electrically connected <FIG. 6 (c)>.

[0005] Thereafter, the frame-like case 5 serving as a wall surface is fixed to the outer peripheral portion of the metal-based insulating circuit board 6 using an adhesive 22 such as silicon or an epoxy type <FIG.
>. Lastly, a liquid sealing resin 12 made of an epoxy resin or the like is injected into the frame-shaped case 5 for sealing and sealing from the outside to enhance reliability, and the power semiconductor device is completed <FIG. e)>.

As described above, the manufacturing process of the conventional power semiconductor device is roughly divided, and as shown in the assembly flowchart of FIG. 5A, an electronic component including a semiconductor element is soldered on a metal-based insulating circuit board. Component mounting process,
An input / output terminal fixing step of soldering external input / output terminals to a metal-based insulated circuit board, and bonding of a frame-shaped case to a metal-based insulated circuit board on which electronic components including semiconductor elements and external input / output terminals are mounted. 4 of the frame fixing step and the insulating resin injecting step of injecting and curing the sealing resin into the inside of the frame-shaped case.
Process.

[0007]

In a conventional power semiconductor device, when a liquid encapsulating resin is injected and cured, a frame-shaped case is formed by forming a wall of the liquid resin accommodating portion. An outer frame fixing step of bonding to a metal-based insulating circuit board serving as a bottom surface of the metal-insulated circuit board, and an external input for fixing external input / output terminals to the circuit pattern on the metal-based insulating circuit board substantially perpendicular to the metal-based insulating circuit board An output terminal fixing step is required.

In the outer frame fixing step, a resin such as silicon or epoxy resin is used as an adhesive, but the bonding operation using such a resin requires a relatively long time, and when a thermosetting adhesive is used. In such a case, equipment such as a thermostat for heating and curing the adhesive is required, and the manufacturing cost is increased.

In the external input / output terminal fixing step, electrical connection and fixing between the external input / output terminals and the circuit pattern on the metal-based insulating circuit board are performed via a solder material. 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 temperature of the power semiconductor device becomes high due to the heat generation of the power semiconductor device itself and an increase in the ambient temperature, etc., the external input / output terminal is connected to the circuit by the difference in the expansion coefficient of the sealing resin. Stress is applied to the solder material which is a 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 downsizing of the metal-based insulating circuit board.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a power semiconductor device which is inexpensive, has higher reliability, and is smaller than conventional products.

[0013]

In order to achieve the above object, a power semiconductor device according to the present invention includes an insulating circuit board having a circuit pattern made of a metal plate embedded therein and a peripheral portion of the insulating circuit board. A frame-shaped case which is integrally erected from the same material and serves as a side wall of the sealing resin accommodating portion, and an electronic component including a semiconductor element electrically connected to a circuit pattern embedded inside the insulating circuit board; and External input / output terminals,
It is characterized by comprising a sealing resin injected and cured into a recess formed by the insulating circuit board and the frame-shaped case.

Further, in the power semiconductor device according to the first aspect, 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 about 90 degrees with respect to the circuit pattern. Pass through the inside of the frame case,
It is characterized by being led out of the frame-shaped case.

[0015]

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 formed of the same resin, and the circuit pattern is formed inside the insulating circuit board by a metal plate. Since the structure is formed, a complicated process of fixing the frame-shaped case to the insulating circuit board is not required. In addition, a circuit pattern can be formed directly below a mounting area for electronic components and the like, and the degree of freedom in designing a circuit pattern is increased.

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 of the frame-shaped case, there is no need to solder the external input / output terminals to the circuit pattern. Since there is no joint made of a solder material between the output terminal and the circuit pattern, the problem of cracking at the joint due to thermal stress or the like is solved.

Further, since an area for soldering the external input / output terminals to the circuit pattern is not required, the size of the insulating circuit board can be reduced.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a power semiconductor device according to the present invention, a frame-shaped case surrounds an insulating circuit board on which electronic components including semiconductor elements and external input / output terminals are mounted, and is formed by the insulating circuit board and the frame-shaped case. In the structure in which the 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. An external input / output terminal passes through the inside of the frame-shaped case and is formed integrally with a circuit pattern inside the insulating circuit board.

Hereinafter, the structure of the power semiconductor device of the present invention will be described.
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 embodiments, the same functional portions as those in the conventional example are denoted by the same symbols.

FIG. 1 is a structural view of a frame-shaped case-integrated insulating circuit board of the present invention, wherein (a) is an internal perspective view from the top side, (b) 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 serving as a side wall of a liquid sealing resin housing portion and an insulating circuit board 6 at the bottom are integrally formed of the same resin.

The frame-shaped case 5 which is integrally formed
As the material of the insulating circuit board 6, a thermoplastic resin having a heat deformation temperature of 230 ° C. or more, for example, 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 created in the desired circuit are connected to 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 about 90 degrees with respect to the output side circuit pattern 2, passes through the inside of the frame-like case 5, and It is led out of the case 5.

In this embodiment, only the external output terminals 4 are formed integrally with the output circuit pattern 2. However, the external input terminals may be formed integrally with the input circuit pattern 1. As a material of 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 as necessary.

Reference numeral 13 denotes a through hole for fixing a screw when mounting to an external device.

FIG. 2 is an external view of the above-described frame-shaped case-integrated insulated circuit board as viewed from above.

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

FIGS. 3A and 3B are structural views in which electronic components including a semiconductor element 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, and a capacitor 8 and a resistance 9 constituting a snubber circuit for protecting the SSR element 7 from external noise are predetermined. Is soldered at the position.

The semiconductor element 7 and the electronic components 8
Lead terminals 9 and 10 are used. The lead terminals 15 are inserted into through holes 16 formed in a circuit pattern exposed from the surface of the insulating circuit board 6, and the lead terminals 15 and the circuit pattern are soldered. Soldered with material. As the solder material, for example, a cream-like melting point of 1
83 ° C. Sn / Pb eutectic solder is used.

Reference numeral 17 denotes an external input connector. The external input connector 17 may be formed integrally with the input-side circuit pattern 1 similarly to the external output terminal 4, and may be an external input terminal that passes through the inside of the frame-shaped case 5 and leads out of the frame-shaped case 5.

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

First, the external input / output terminals 3, 4 formed integrally with the input side circuit pattern 1, the output side circuit pattern 2, and the circuit patterns 1, 2 made of a metal plate having a thickness of about 0.3 to 0.5 mm. Is arranged 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 formed of the same resin by so-called insert molding, whereby the frame-shaped case integrated type is formed. The insulating circuit board 23 is completed (FIG. 4A).

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

Finally, the liquid sealing resin 1 is placed in a concave portion surrounded by the insulating circuit board 6 and the frame case 5 formed 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. 4C).
>.

According to the power semiconductor device of the present invention configured as described above, as shown in the comparative diagram of the assembly flowchart of the conventional power semiconductor device of FIG. This eliminates the need for an input / output terminal fixing step of soldering the external input / output terminals to the circuit pattern and an outer frame fixing step of bonding the frame-shaped case to the insulating circuit board, thus simplifying the steps.

[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 formed of the same resin, and the inside of the insulating circuit board is formed. Since the circuit pattern is formed by using a metal plate, a complicated process of bonding the frame-shaped case to the insulating circuit board is not required, and the manufacturing cost can be reduced.

Further, a circuit pattern can be formed immediately below a mounting area for electronic parts and the like, and the degree of freedom in designing a circuit pattern is increased.

According to the power semiconductor device of the second aspect,
The external input / output terminals are formed integrally with the circuit pattern and passed through the inside of the frame-shaped case to the outside.Therefore, there is no need to solder the external input / output terminals to the circuit pattern, which can reduce manufacturing costs. Become.

Furthermore, since there is no solder joint between the external input / output terminal and the circuit pattern, the problem of cracking at the joint due to thermal stress or the like is eliminated.
A highly reliable power semiconductor device can be provided.

Further, since a region for soldering the external input / output terminals to the circuit pattern is not required, the size of the power semiconductor device can be reduced.

[Brief description of the drawings]

FIG. 1 is a structural view of a frame-shaped case-integrated insulated circuit board of the present invention, wherein (a) is an internal perspective view from the top side, and (b)
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 insulated circuit board of the present invention as viewed from the upper surface side.

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

4 (a) to 4 (c) are schematic views showing steps of manufacturing a power semiconductor device of the present invention.

FIG. 5 is a comparison diagram of an assembly flowchart of a power semiconductor device of the related art and the present invention.

6 (a) to 6 (e) are schematic views showing steps of manufacturing a power semiconductor device according to a conventional example.

[Explanation of symbols]

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

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 23/48 H01L 23/08

Claims (2)

(57) [Claims] An insulated circuit board having a circuit pattern made of a metal plate embedded therein, and an upright portion integrally formed of the same material from a peripheral portion of the insulated circuit board, and a side wall of a sealing resin accommodating portion. A frame-shaped case, an electronic component including a semiconductor element electrically connected to the circuit pattern embedded in the insulating circuit board, and an external input / output terminal; and the insulating circuit board and the frame-shaped case. And a sealing resin injected and cured into the recess formed by the steps (a) and (b). 2. 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 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 of the frame-shaped case.