Combined type high-power semiconductor chip

Abstract

The invention provides a combined type high-power semiconductor chip and belongs to the technical field of power electronic semiconductor devices. The combined type high-power semiconductor chip comprises a package body, a chip, molybdenum pieces and copper pieces, wherein the package body comprises an inner abnormally-shaped annular ring and an outer abnormally-shaped annular ring; an inward protruded clamping ring is arranged on the inner wall of the upper part of the outer abnormally-shaped annular ring (102); an inward protruded limiting block is arranged at the bottom of the outer abnormally-shaped annular ring (102); a groove which is combined with the clamping ring on the inner wall of the outer abnormally-shaped annular ring in a matched way is arranged on the outer edge of the inner abnormally-shaped annular ring (107); an inward protruded limiting block is arranged at the upper end of the inner abnormally-shaped annular ring (107); a lower copper piece (101), a lower molybdenum piece (103), the chip (104) and the inner abnormally-shaped annular ring are arranged in the outer abnormally-shaped annular ring; and an upper molybdenum piece (105) and an upper copper piece (106) are arranged in the inner abnormally-shaped annular ring. By the combined type high-power semiconductor chip, the chip, the molybdenum pieces and the copper pieces can be compressed with one another according to pressure of an outer clamping device, and aims of high product yield, low thermal stress, improvement on thermal cycle frequency, low cost, and convenience and quickness of assembly arefulfilled.

Description

Technical field: [0001] The invention relates to a combined high-power semiconductor chip, which belongs to the technical field of power electronic semiconductor chips. Background technique: [0002] Power electronic semiconductor chips refer to semiconductor devices such as rectifier diodes, fast rectifier diodes, thyristors and fast thyristors in the field of power electronic devices. Most of the low-power chip anode and cathode are welded together with soft solder and molybdenum sheet to form a die. The chips with high power above 200A are welded together by molybdenum and silicon chips. Generally, the molybdenum sheet is welded on the anode side of the semiconductor chip. Welding directly places the chip between two molybdenum sheets, and relies on the pressure of the external clamping device to press the chip and the molybdenum sheet together. [0003] However, both of the above methods have disadvantages: [0004] The welding type has a large thermal stress, and the...

AI Technical Summary

Problems solved by technology

[0008] Its technical effect is: due to the use of special-shaped annular rings to implement a combined positioning structure for high-power semiconductor chips, molybdenum sheets, and copper sheets, the chips, molybdenum sheets, and copper sheets are pressed together by relying on the external clamping device, which not only protects The fragile chip is protected from the impact of external force, and the thermal stress caused by the deformation of the chip caused by welding is eliminated. The difference in thermal expansion coefficient between the copper sheet and the molybdenum sheet is compensated by the sliding of the pressure surface, realizing the chip, Molybdenum sheets are free of welding and reduce thermal stress; at the same time, the bottom of the outer special-shaped annular ring is provided with an inwardly convex limit block, the upper end of the inner special-shaped annular ring is provided with an inwardly convex limit block, and the outer surface of the inner special-shaped annular ring There is a groove on the edge that matches and combines with the snap ring on the inner wall of the outer special-shaped annular ring, so that the chip, the upper and lower molybdenum sheets and the upper and lower copper sheets can be positioned accurately, which solves the problem of difficult positioning and high cost of the traditional welding-free pressing type. It achieves convenient and fast assembly, high efficiency, improves the number of thermal fatigue and service life, and optimizes the electrical parameters of the chip

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