JPH09260557A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To electrically insulate a semiconductor device from a cooling body, and improve the heat radiation, with a flat IGBT(insulated gate bipolar transistor). SOLUTION: A solder sheet 7, a metallic plate 5 for takeout of currents, a solder sheet 7, and an insulating substrate 6 are stacked on the emitter terminal 2 of a flat IBGT 1. Likewise, also on the collector terminal side 3, a solder sheet 7, a metallic plate 5 for takeout of currents, a solder sheet 7, and an insulating substrate 6 are stacked. The insulating board 6 is pressed with a flat press not shown in the figure, and the solder sheet 7 is fused by heating these parts and then is cooled to solder each part. The insulating board 6 is manufactured by covering both sides of an insulating board 10 such as an alumina plate, an aluminum nitride plate, etc., with metallic films 11. By constituting it this way, the flat IGBT 1 is insulated electrically from the cooling body not shown in the figure, but thermally good conductivity can be secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended for a power device such as an insulated gate bipolar transistor (IGBT) and the like. A main electrode (emitter) and a control electrode (gate) are provided on one main surface of a substrate, and another main surface is provided. On the second main electrode (collector)
The present invention relates to a semiconductor device in which a plurality of semiconductor chips having the above are incorporated in the same package, and a manufacturing method thereof.

[0002]

2. Description of the Related Art A pressure contact type flat IGBT mounted in a ceramic package equivalent to a conventional thyristor or GTO.
Has been proposed. Unlike the GTO and the like, the flat IGBT has a MOS structure on the pressing surface, and therefore, in order to ensure initial characteristics and long-term reliability, it is necessary to consider not pressing the MOS portion such as the gate electrode. Therefore, a structure is provided in which a collector electrode for both cooling and energization is provided in a region where the gate electrode is not formed, and the collector electrode is externally pressed through the contact terminal body and the common electrode plate on the package side. . This common electrode plate is pressurized by a cooling body, a load current is passed through the IGBT chip, and heat generated in the IGBT chip is dissipated.

[0003]

However, when a semiconductor device is used in an inverter or a converter, it is often easier to use the electrically insulating material if the cooling body and the semiconductor device have good heat dissipation. In the conventional flat IGBT, a current flows from the common electrode plate to the cooling body, so that the common electrode plate and the cooling body are not electrically or thermally insulated from each other. Therefore, the semiconductor device is not easy to use.

The object of the present invention is to solve the above problems,
It is an object of the present invention to provide a flat semiconductor device in which heat conduction between the cooling body and the common electrode plate is good but electrically insulated.

[0005]

In order to achieve the above object, a semiconductor chip of MOS structure having a first main electrode and a control electrode on a first main surface and a second main electrode on a second main surface is provided. A plurality of juxtaposed devices are mounted in a flat package having a pair of common electrode plates with both surfaces exposed and an insulating outer tube interposed therebetween, and the first main electrode of the semiconductor chip and the common electrode on the side of one package facing the first main electrode. Exposure of both common electrode plates in a semiconductor device in which a contact terminal body that also functions as pressure, conductivity, and heat dissipation is interposed between the plate and the second main electrode is fixed on the common electrode plate on the other package side. An insulating substrate is fixed on the surface. A current extraction metal plate may be sandwiched and fixed between both common electrode plates and the insulating plate. This insulating substrate is preferably made of alumina (Al ₂ O ₃ ) or aluminum nitride (NAl). Further, it is effective to provide an insulating ring on the outer peripheral portion of the insulating substrate. The semiconductor chip of the MOS structure is an insulated gate bipolar transistor, a MOS control thyristor or a MOS transistor, and a free wheel diode is incorporated side by side with the semiconductor chip of the MOS structure in the same flat package,
It is preferable to provide a contact terminal body that also serves as pressure, conductivity, and heat dissipation between the common electrode on one package side and the free wheel diode.

As a method of manufacturing the semiconductor device, each solder sandwiched between the insulating substrate and the common electrode plate or between the insulating substrate, the current extracting metal plate and the common electrode plate is pressed by a flat press, and A method is preferable in which the insulating substrate and the common electrode plate are solder-bonded by being heated and melted and then cooled. By providing a metal plate for current extraction as in the above configuration, an insulating substrate made of an alumina plate or an aluminum nitride plate having good thermal conductivity is heated on the surface of the metal plate while pressing it with a flat press. By cooling and soldering, it is possible to ensure electrical insulation between the cooling body and the IGBT, and with this configuration, the exposed surface of the insulating substrate that contacts the cooling body can be flattened, and the heat generated by the IGBT Can be smoothly dissipated to the cooling body.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view of the essential parts of a first embodiment of the present invention, in which FIG. 1 (a) is an exploded view of each part and FIG. 1 (a) is a side view of a finished product. It is a figure. In FIG. 1, a solder sheet 7, a current extracting metal plate 5, a solder sheet 7, and an insulating substrate 6 are laminated on an emitter terminal 2 (one common electrode plate) of a flat IGBT 1. Similarly, on the collector terminal 3 (the other common electrode plate) side, the solder sheet 7, the current extracting metal plate 5, the solder sheet 7, and the insulating substrate 6 are laminated. The insulating substrate 6 is pressed by a flat press (not shown), these components are heated to melt the solder sheet 7, and cooled to solder each component. The insulating substrate 6 has a metal film 11 on both sides of an insulating plate 10 (thermally good conductor) such as an alumina plate or an aluminum nitride plate.
It is manufactured by coating.

FIG. 2 is an external view of the flat IGBT, FIG. 2 (a) is a plan view, and FIG. 2 (b) is a side view. In FIG. 2, an emitter terminal 2, a collector terminal 3, and a gate terminal 4 are welded to an insulating cylinder 9 (also called a ceramic case) made of ceramic. A semiconductor chip and a contact terminal body (not shown) are housed in the insulating cylinder 9.

FIG. 3 is a block diagram of a metal plate for extracting electric current.
FIG. 1A is a plan view, and FIG. 1B is a side view. FIG.
In, the current terminal 5a connected to the external circuit is provided on the side surface of the current extraction metal plate 5. A mounting hole 5b is opened in the current terminal 5a. This current terminal 5
a is an emitter terminal 2 and a collector terminal 3 of the flat IGBT 1.
It is also possible to dispose the metal plate 5 for current extraction in the structure by omitting it from the configuration.

4A and 4B are structural views of the insulating substrate. FIG. 4A is a plan view and FIG. 4B is a side view. In FIG. 4, the insulating substrate 6 has a structure in which a metal film 11 is coated on both surfaces of an insulating plate 10 such as an alumina plate or an aluminum nitride plate having good thermal conductivity and excellent electric insulation. FIG. 5 shows a side view of the second embodiment of the present invention. By providing the insulating ring 8 around the insulating plate 10 forming the insulating substrate 6 and increasing the creeping distance of the flat IGBT 1 including the insulating substrate 6 sandwiched between the cooling bodies (not shown), the creeping discharge of the flat IGBT 1 Prevent.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a first embodiment of the present invention,
(A) is a view of each part disassembled, (b) is a side view of the finished product

FIG. 2 is an external view of a flat IGBT, (a) is a plan view,
(B) is a side view

FIG. 3 is a configuration diagram of a metal plate for current extraction, (a) is a plan view and (b) is a side view.

4A and 4B are structural views of an insulating substrate, where FIG. 4A is a plan view and FIG.
Is a side view

FIG. 5 is a side view of the second embodiment of the present invention.

[Explanation of symbols]

 1 Flat IGBT 2 Emitter Terminal 3 Collector Terminal 4 Gate Terminal 5 Current Extraction Metal Plate 5a Current Terminal 5b Mounting Hole 6 Insulating Substrate 7 Solder Sheet 8 Insulation Ring 9 Insulation Tube 10 Insulation Plate 11 Metal Film

Claims (6)

[Claims] 1. A pair of common semiconductor chips having a first main electrode and a control electrode on a first main surface and a plurality of MOS structure semiconductor chips each having a second main electrode on a second main surface, which are arranged side by side. Built in a flat package having an insulating outer tube interposed between the electrode plates, pressure, conduction, between the first main electrode of the semiconductor chip and the common electrode plate on the one package side facing the first main electrode.
In a semiconductor device in which a contact terminal that also serves as heat dissipation is interposed and a second main electrode is fixed on the common electrode plate on the other package side, an insulating substrate is fixed on the exposed surface of both common electrode plates. A semiconductor device characterized by: 2. The semiconductor device according to claim 1, wherein the current extracting metal plate and the insulating substrate are fixed on the exposed surfaces of both common electrode plates. 3. The semiconductor device according to claim 1, wherein an insulating ring is provided on an outer peripheral portion of the insulating substrate. 4. The semiconductor device according to claim 1, wherein the insulating substrate is made of alumina (Al ₂ O ₃ ) or aluminum nitride (NAl). 5. A semiconductor chip having a MOS structure is an insulated gate bipolar transistor, a MOS control thyristor or a MOS transistor, and a freewheel diode is incorporated in parallel with the semiconductor chip having a MOS structure in the same flat package, and one package is provided. 2. The semiconductor device according to claim 1, further comprising: a contact terminal body that also serves as a pressurizing member, a conductive member, and a heat sink between the common electrode on the side and the free wheel diode. 6. A pair of common semiconductor chips, each having a first main electrode and a control electrode on the first main surface and a plurality of MOS structure semiconductor chips each having a second main electrode on the second main surface, arranged side by side to expose both surfaces. Built in a flat package having an insulating outer tube interposed between the electrode plates, pressure, conduction, between the first main electrode of the semiconductor chip and the common electrode plate on the one package side facing the first main electrode.
In a semiconductor device in which a contact terminal that also serves as heat dissipation is interposed and a second main electrode is fixed to the common electrode plate on the other package side, external lead terminals are provided on the side surfaces of both common electrode plates, Further, in a semiconductor device in which an insulating substrate is fixed on the exposed surfaces of both common electrode plates, each solder sandwiched between the insulating substrate and the common electrode plate or between the insulating plate, the current extraction metal plate and the common electrode plate. Is a method of manufacturing a semiconductor device in which the insulating substrate and the common electrode plate are solder-joined by being pressed by a flat press, heated and melted, and cooled.