Silicon carbide MOSFET device and process method thereof

Abstract

The invention provides a silicon carbide MOSFET device, and the device comprises a high-concentration N-type drain electrode and drain electrode metal; an N-type epitaxial layer is arranged on the high-concentration N-type drain electrode to serve as a drift region of the MOSFET device, a spaced P-type body region is arranged above the N-type epitaxial layer, a high-concentration N-type source electrode is arranged in the P-type body region, N-type source electrodes are arranged on the surface of the N-type epitaxial layer, high-concentration first P-type source electrodes are arranged on the outer sides of the N-type source electrodes, a gate oxide layer is further arranged on the surface of the N-type epitaxial layer, the gate oxide layer starts and ends above two adjacent N-type source electrodes, gate polycrystalline silicon is arranged above the gate oxide layer, source electrode metal is further arranged on the surfaces of the N-type source electrodes and the surface of the first P-type source electrode, and an insulating dielectric layer is arranged between the source electrode metal and the grid electrode polycrystalline silicon for isolation; the P-type body region and the N-type source electrode are recessed inwards at intervals in the Y direction, the P-type body region surrounds the N-type source electrode, and a second P-type source electrode with high concentration is arranged in the recessed region. The short-circuit capability of the device is improved.

Description

technical field [0001] The invention relates to a semiconductor device, in particular to a silicon carbide power semiconductor device. Background technique [0002] As a third-generation semiconductor material, silicon carbide (SiC) has the advantages of wide bandgap, high critical breakdown electric field, and high saturation drift speed compared with existing silicon materials. MOSFET devices made of SiC materials have the same resistance to Compared with the silicon-based MOSFET with low voltage level, it has the advantages of low on-resistance, small size, and fast switching speed. [0003] However, once the SiC MOSFET device is short-circuited in the application, the high voltage and high current will cause the device to generate a lot of heat in a very short time, and because of the small size of the SiC MOSFET, it is difficult for a large amount of heat to pass through the small device area in a short time Therefore, improving the short-circuit capability of SiC MOSF...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a silicon carbide MOSFET device and its process method, to overcome the problem of insufficient short-circuit capability of SiC devices in the prior art, and to improve the short-circuit capability of SiC devices

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