JPH098224A - Semiconductor module and power converter - Google Patents

Abstract

(57) [Summary] [Structure] In a semiconductor module in which a common output terminal of a plurality of arranged semiconductor chips is a flat plate, and is stacked via an insulator, and is taken out to the outside, the semiconductor chip is aluminum nitride. What is claimed is: 1. A semiconductor module characterized in that a copper pattern, which is metallized on a plate, is fixed to the plate via solder, and is held in pressure contact with a cooling fin via an insulating material and grease. A plurality of semiconductor chips arranged in an insulating frame, a common output terminal of the semiconductor chips is a flat plate,
In addition, in the power conversion device including a semiconductor module that is superposed via an insulator and taken out to the outside, the flat plate terminal is directly connected and fixed to the capacitor terminal outside the insulating frame. . [Effect] A semiconductor module having excellent cooling efficiency and long life is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor module and a power converter, and more particularly to a semiconductor module and a power converter suitable for use in a high power type power module such as an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Publication No. 5-25392 is known as a low power semiconductor device. According to this type of device, a common collector terminal plate is arranged on an upper surface of a metal substrate via an insulating plate, and a semiconductor chip and a common emitter terminal plate arranged in parallel via the insulating plate are arranged and fixed thereon. What has been done is disclosed.

Further, US Pat. No. 5,049,973 discloses a semiconductor chip fixed to a terminal plate (wiring bus bar) and fixed to a diffusion plate together with other semiconductors.

[0004]

[Problems to be Solved by the Invention] The former Japanese Patent Fairness 5-2
According to Japanese Patent No. 5392, since the semiconductor chip and the terminal plate or the metal substrate and the terminal plate are fixed to each other, they have a relatively small capacity and are effective for those with a small heat generation, but are joined to each other for those with a large heat generation. Since the parts are made of different materials, stress is generated, and the reliability of bonding is unavoidable.

Further, the latter US Pat. No. 5,049,973 discloses a semiconductor chip and an external connection bus bar fixed to a cooling fin, and the semiconductor chip and the external connection bus bar are wire-connected. . According to this content, as in the former technique, a semiconductor device having a relatively small capacity is shown, and a copper alloy frame to which a chip is soldered is joined to a cooling fin made of nickel. Since they are made of different materials, stress is generated when the temperature is high, and the reliability of bonding remains low.

One of the objects of the present invention is to provide excellent cooling efficiency,
An object is to provide a long-life semiconductor module.

One of the objects of the present invention is to provide a power converter which is small in size and excellent in assembling.

[0008]

SUMMARY OF THE INVENTION The present invention is a semiconductor module in which a plurality of semiconductor chips arranged in common have a common output terminal as a flat plate, and the semiconductor chips are stacked via an insulator and taken out to the outside. The semiconductor chip is achieved by pressing a metal pattern, which is metalized on an aluminum nitride plate, through a solder, and fixing the semiconductor chip to a cooling fin through an insulating material and grease.

One aspect of the present invention is a semiconductor chip in which a plurality of semiconductor chips are arranged in an insulating frame, a common output terminal of the semiconductor chips is a flat plate, and the semiconductor chips are stacked with an insulator interposed therebetween and taken out to the outside. A power conversion device comprising a module, which is achieved by directly connecting and fixing the flat plate terminal to a capacitor terminal outside the insulating frame.

The present invention is preferably accomplished by arranging a common flat plate output terminal so as to project outside the insulating frame on the side opposite to the capacitor.

[0011]

In this structure, the chip of the semiconductor module is configured such that the metal pattern on the insulating plate, which is fixed to the copper pattern via solder, is fixed to the cooling fin via the insulating plate and grease. , Even with a relatively large capacity semiconductor module, there is no concern about thermal deformation due to heat generation,
Can dissipate heat effectively. In particular, since the place to be connected by solder is just below the semiconductor chip, stress exerted on the solder is small and the life is improved even if the temperature rises under severe control.

Further, since the flat plate terminals are superposed and directly connected and fixed to the terminals of the capacitor outside the insulating frame, it is possible to provide a power conversion device value which is effective in handling and assembling and which is highly productive.

From the viewpoint of the electric circuit, the inductance of the circuit is determined by the inductance of the wiring bus bar from the semiconductor chip to the filter capacitor such as the electrolytic capacitor, and the turn-up voltage occurs at L × di / dt at the time of turn-off.
This is superimposed on the power supply voltage and applied to the collector-emitter of the semiconductor chip. Therefore, L can be reduced.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view of a device showing one phase of a power conversion device, and FIG.

In the figure, a cooling fin 1 is made of an aluminum material having a thickness of several centimeters, and a power conversion device 2 and an electrolytic capacitor 3 corresponding to each phase are arranged and fixed on the upper surface thereof.

The structure of the power conversion device 2 will now be described with reference to FIG. 2. On the upper surface of the insulating plate 4 of each phase made of aluminum nitride, metal films 5, 51 made of copper material are partially formed. Is formed. Each IGBT chip (semiconductor chip) 6 is fixed on the metal film by soldering, and each I
The upper surface electrode of the GBT chip (semiconductor chip) 6 is connected to another adjacent metal film 7 and the upper surface electrode of the diode chip 8 via a wire.

On the other hand, the output terminals 9 and 10 of the common collector and emitter of the semiconductor chip serving as a bus bar, respectively.
And the common output terminal 11 of the emitter and the collector is the insulating frame 1
2 is molded and held by the mold 2, and one end of the plate is taken out of the insulating frame 12 and arranged. Further, most of the output terminals 9 and 10 are overlapped with each other via the insulating plate 13, and the inner tip is brazed and fixed to the metal film 5, and the outer tip is brazed and fixed to another metal film 51. One end outside the insulating frame 12 extends vertically along the insulating frame and is electrically connected to the respective terminals 3A and 3B of the capacitor 3 arranged on the cooling fin 1.
On the other hand, the output terminal 11 is similarly arranged and fixed in the opposite direction to the terminals 9 and 10. The output terminals 9 and 1
Input terminals 14, 15, 16, 17 such as gates are molded and held in an insulating frame perpendicular to the directions 0, 11. In the device constructed in this manner, the two peripheral surfaces of the insulating plate 4 and the lower peripheral surface of the insulating frame 12 are fixed by an adhesive 18 such as silicon, and after filling the insulating gel 19, the lid 20 is closed. To form one device. Then, this apparatus is pressed and held on the cooling fin 1 through the metal plate 21 made of copper and the silicon grease 22.

In the above device, the insulating plate 4 other than the fixed two-sided surface is projected outside the insulating frame, so that this part is held and fixed by pressure contact. That is,
Several screw holes are previously formed on the cooling fin,
After arranging the device, a mounting screw 24 is tightened in this screw hole via a rigid support plate 23. This support plate 2
A coil spring (may be a leaf spring or the like) 25 is previously disposed between the insulating plate 3 and the insulating plate 4 via a guide pin 26, and the insulating plate is firmly pressed against each other as the tightening force of the mounting screw increases.

In such a structure, the semiconductor module chip has a structure in which a metal pattern on an insulating plate, which is fixed to a copper pattern through solder, is fixed to a cooling fin through the insulating plate and grease. Even in a semiconductor module having a relatively large capacity, heat can be effectively dissipated without fear of thermal deformation due to heat generation. In particular, since the place to be connected by solder is just below the semiconductor chip, stress exerted on the solder is small and the life is improved even if the temperature rises under severe control.

Further, since the flat plate terminals are superposed and directly connected and fixed to the terminals of the capacitor outside the insulating frame, it is possible to provide a power conversion device value which is effective in handling and assembling and which is highly productive.

From the viewpoint of the electric circuit, the inductor of the circuit is determined by the inductance of the wiring bus bar from the semiconductor chip to the filter capacitor such as the electrolytic capacitor, and at turn-off, a rising voltage is generated at L × di / dt, which is superimposed on the power supply voltage. And applied to the collector-emitter of the semiconductor chip. Therefore, since L can be made small, there is also an advantage that the snubber circuit can be omitted.

In the above embodiment, the support plate 23 is attached to the insulating frame 1.
Although it is described as a separate body from 2, the integrally molded product may be fixed via a spring, or the insulating frame itself may be clamped and fixed via a spring, and the same effect can be obtained.

[0023]

As described above, the semiconductor module chip is fixed to the metallized copper pattern on the insulating plate via solder, and the chip is fixed to the cooling fin via the insulating plate and grease, resulting in excellent cooling efficiency. It is possible to provide a long-life semiconductor module.

Further, by stacking the flat plate terminals and directly connecting and fixing the flat terminals to the terminals of the capacitor outside the insulating frame, it is possible to provide a power converter having excellent assemblability.

[Brief description of drawings]

FIG. 1 is a perspective cross-sectional view of a main part showing a part of a power conversion device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

3 is a circuit diagram in FIG.

FIG. 4 is a layout diagram in the application of the present invention.

[Explanation of Codes] 1 ... Cooling fin, 3 ... Capacitor, 4 ... Insulating plate, 5, 5
1 ... Copper pattern (metal film), 6 ... Semiconductor chip, 9, 1
0, 11 ... Output terminal, 12 ... Insulating frame, 21 ... Metal plate, 2
3 ... Support plate.

Claims (9)

[Claims] 1. A semiconductor module in which a common output terminal of a plurality of arranged semiconductor chips is formed into a flat plate, and is stacked via an insulator and taken out to the outside, wherein the semiconductor chips are metalized to an insulating plate. What is claimed is: 1. A semiconductor module, wherein a copper pattern fixed to a copper pattern with solder is held in pressure contact with a cooling fin via a metal plate and grease. 2. The semiconductor module according to claim 1, wherein a copper pattern is pressure-welded. 3. The semiconductor module according to claim 1, wherein the grease is silicon gel. 4. A power converter comprising a plurality of semiconductor chips arranged in an insulating frame, a common output terminal of the semiconductor chips being a flat plate, superposed via an insulator, and taken out to the outside. In the device, the terminal of the flat plate is directly connected and fixed to the capacitor terminal outside the insulating frame, and the power converter. 5. The power converter according to claim 1, wherein the terminals of the flat plate are arranged along the outer wall of the insulating frame and are connected so as to cross the capacitor terminals. 6. The semiconductor chip according to claim 4, wherein the semiconductor chip is secured to a copper pattern metallized on an aluminum nitride plate via solder, and is held in pressure contact with a cooling fin via a metal plate and grease. A power converter characterized by the above. 7. The power conversion device according to claim 6, wherein the copper pattern is pressed via spring pressure. 8. The copper pattern according to claim 6 or 7, wherein both ends of the copper pattern protruding from the insulating frame are pressed and held by a support plate held by the cooling fin and a spring elastically held by the support plate. A power conversion device characterized by: 9. A power supply comprising a plurality of semiconductor chips arranged in an insulating frame, a semiconductor module in which a common output terminal of the semiconductor chips is a flat plate, and the semiconductor chips are superposed on each other via an insulator and taken out to the outside. In the conversion device, the stacked flat plate terminals are directly connected and fixed to the capacitor terminals outside the insulating frame, and the common flat plate output terminal is arranged to project outside the insulating frame on the side opposite to the capacitor. Power conversion device.