JPH0650358U - Composite semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] The difference in thermal expansion between the ceramic substrate and the external lead-out terminal board was absorbed by the expansion and contraction of the external lead-out terminal board in the horizontal direction to improve the reliability of the device itself. To provide a composite semiconductor device. [Structure] A notch 21 is formed in the horizontal portion 19 of the external lead-out terminal 18. As a result, even if a difference in thermal expansion occurs between the ceramic substrate 3 and the external lead-out terminal 18 due to the heat generated during operation, the cut 2 in the horizontal portion 19 of the external lead-out terminal 18
1 can expand and contract in the horizontal direction to absorb the shearing stress generated between the ceramic substrate 3 and the external lead-out terminal 18. Therefore, stress is not applied to the upper surface electrode of the semiconductor chip 5, and the reliability of the composite semiconductor device itself can be improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a composite semiconductor device in which a plurality of semiconductor chips are enclosed in an insulating case, and more particularly to the structure of its external lead terminal.

[0002]

[Prior art]

 A schematic structure of a conventional composite semiconductor device of this type is shown in FIGS. In these figures, a ceramic substrate 3 is placed and fixed on a heat dissipation plate 1 with a metallized layer 2 interposed therebetween. A plurality of semiconductor chips 5 are placed and fixed on the ceramic substrate 3 via a pedestal 4, and one external lead-out terminal 6 is fixed on the substrate 3. Electrode plates 7 are fixed at predetermined positions on the semiconductor chip 5, respectively, and the other external lead-out terminals 8 commonly connected to the respective electrode plates 7 are placed and fixed, and are continuously connected to the horizontal portion at L level. One end of the vertical portion bent in a letter shape is led out so as to face one end of the other external lead terminal 6.

An insulating case 9 having openings at both ends is fixed to the heat dissipation plate 1 so as to surround each of these members, and the inside of the insulating case 9 is filled with a gel coating agent 10 on the lower side thereof. The sealing resin 11 is filled and cured on the coating agent 10. The composite semiconductor device having the above structure is used by attaching the heat dissipation plate 1 to an external member (not shown) through the through hole 1a. However, the structure of the conventional composite semiconductor device has the following problems.

[0004]

[Problems to be solved by the device]

 That is, in the conventional composite semiconductor device, since there is a difference between the thermal expansion of the ceramic substrate 3 in the longitudinal direction and the thermal expansion of the other external terminal plate 8, horizontal shear stress is applied to the upper surface electrode of the semiconductor chip, and the semiconductor device is This adversely affected the electrical characteristics of the device, leading to a decrease in the reliability of the device itself.

[0005]

[The purpose of the device]

 The present invention has been made to solve the above problems, and absorbs the difference in thermal expansion between the ceramic base plate and the external lead-out terminal plate by the horizontal expansion and contraction of the external lead-out terminal plate. It is an object of the present invention to provide a composite semiconductor device in which the reliability of the device itself is improved without adversely affecting the electrical characteristics and the like.

[0006]

[Means for solving problems]

 The composite semiconductor device of the present invention is a composite semiconductor device having an external lead terminal for connecting electrodes provided on the upper surfaces of a plurality of semiconductor chips mounted on a heat sink via an insulating substrate. It consists of a plate-shaped member that has a horizontal portion that is arranged substantially parallel to the heat sink and a vertical portion that continuously rises at a right angle to this horizontal portion, and has a shape in which a cut is made from at least one side surface. It is characterized by having.

[0007]

[Action]

 In the composite semiconductor device of the present invention, when a difference in thermal expansion occurs between the ceramic substrate and the external lead-out terminal due to heat generation during operation, the external lead-out terminal expands and contracts in the horizontal direction through the notch, It absorbs the shear stress generated between the ceramic substrate and the external lead-out terminal. Therefore, stress is not applied to the upper surface electrode of the semiconductor chip, the electrical characteristics are not impaired, and the reliability of the device itself is improved.

[0008]

【Example】

 Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a vertical sectional view of a composite semiconductor device of the present invention, and FIG. 2 is a plan view of the same. In this embodiment, a composite semiconductor device having three semiconductor chips will be described. In these figures, three ceramic substrates 3 having double-sided metallized layers 2 and 2 are linearly arranged in the longitudinal direction on a heat dissipation plate 1 and fixed by a solder (not shown). Next, the semiconductor chip 5 fixed in advance on the pedestal 4 with a high-temperature solder is placed on the ceramic substrate 3 together with the pedestal 4. At the same time, the connection terminal 12, the internal terminal 13 and the external lead-out terminal 18 of the present invention are placed respectively and fixed by soldering.

The external lead-out terminal 18 has the following features. That is, as shown in the plan view of FIG. 2 and FIGS. 3 to 5, the external lead-out terminal 18 is provided with a horizontal portion 19 arranged substantially parallel to the heat dissipation plate 1 and a rectangular portion continuous with the horizontal portion 19. It consists of a vertical portion 20 that stands up. Further, the horizontal portion 19 is provided with a cut 21 at a substantially right angle from at least one side surface. The tip portion 21a of the cut 21 has an acute angle shape, and is designed so that the expansion and contraction in the horizontal direction due to thermal expansion can be easily performed from the apex portion. Further, the horizontal portion 19 is provided with a plurality of holes 22. This hole 22 is not always necessary, but it is for helping the spread of the solder when soldering with the internal terminal 13. The holes 23 provided in the vertical portion 20 are used for screwing to an external member.

The external lead-out terminal 18 is fixed to the internal terminal 13. Next, the insulating case 9 is placed on the heat dissipation plate 1, and as shown in FIG. 1, the gel coating agent 10 is filled to such an extent that the horizontal portion 19 of the external lead-out terminal 18 is buried. The sealing resin 11 is filled and cured on the agent 10. Instead of using the gel coating agent 10 and the sealing resin 11 described above, the upper end opening of the insulating case 9 may be covered with a lid (not shown). In the composite semiconductor device having the above structure, since the notch 21 is formed in the horizontal portion 19 of the external lead-out terminal 18, the difference in thermal expansion between the ceramic substrate 3 and the external lead-out terminal 18 is caused by the heat generated during operation. If the horizontal portion 19 of the external lead-out terminal 18 is expanded and contracted in the horizontal direction by the notch 21, the shearing stress generated between the ceramic substrate 3 and the external lead-out terminal 18 is absorbed. You can Therefore, stress is not applied to the upper surface electrode of the semiconductor chip 5, and the reliability of the composite semiconductor device itself can be improved.

[0011]

[Effect of device]

 As described above, in the composite semiconductor device of the present invention, the horizontal portion of the external lead-out terminal is provided with the notch for easy expansion and contraction, so that the thermal expansion due to the heat generation during operation can be easily absorbed, and the semiconductor chip Since it is not stressed, it can withstand long-term use, and since it does not impair electrical characteristics, it has the effect of improving the reliability of the device itself.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a composite semiconductor device according to an embodiment of the present invention.

FIG. 2 is a plan view of the composite semiconductor device.

FIG. 3 is a plan view of an external lead terminal used in the composite semiconductor device.

FIG. 4 is a side view of the same.

FIG. 5 is a perspective view of the same.

FIG. 6 is a vertical cross-sectional view of a conventional composite semiconductor device.

FIG. 7 is a plan view of the conventional composite semiconductor device.

[Explanation of symbols]

 1 heat sink 2 metallization layer 3 ceramic substrate 4 pedestal 5 semiconductor chip 9 insulating case 10 gel-like coating agent 11 sealing resin 12 connecting terminal 13 internal terminal 18 external lead-out terminal 19 horizontal part 20 vertical part 21 notch 22 hole

Claims (1)

[Scope of utility model registration request] 1. A composite semiconductor device having an external lead terminal for connecting electrodes provided on the upper surfaces of a plurality of semiconductor chips mounted on a heat sink via an insulating substrate, wherein the external lead terminal is substantially on the heat sink. It is composed of a plate-shaped member having a horizontal portion arranged in parallel and a vertical portion continuously rising at a right angle to the horizontal portion, and the horizontal portion has a shape in which a cut is made from at least one side surface. And a composite semiconductor device.