Silicon carbide MOSFET (Metal Oxide Semiconductor Field Effect Transistor) structure having self-aligned channels and manufacturing method thereof

Abstract

The invention discloses a silicon carbide MOSFET (Metal Oxide Semiconductor Field Effect Transistor) structure having self-aligned channels and a manufacturing method thereof. P+ contact of the silicon carbide MOSFET structure is in a groove between N+ source table surfaces and is in multi-surface contact with a P type base region; the P type base region is formed on an N- epitaxial wafer by utilizing polycrystalline silicon mask ion injection; SiO2 is deposited on polycrystalline silicon and a side wall is formed through etching; an N+ source region is formed by injection in the P type base region through a self-aligned process; the N+ source region is locally etched onto the P type base region; the P+ contact is formed by ion injection in an etched region; the device is in source / drain ohmic contact by utilizing an alloy self-aligned process; one end of an N+ substrate is used as a drain; one end of a gate medium layer is used as a grid; and one ends of a P+ region and an N+ region are used as sources. According to the invention, a stripping process is avoided; metal is prevented from serving as an ion injection barrier layer; simultaneously, compared with the traditional process, the method can have the photoetching times reduced by one; and the accuracy of the boundary of a P+ contact region is improved.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a channel self-aligned silicon carbide MOSFET structure and a manufacturing method thereof. Background technique [0002] Silicon carbide material has excellent physical and electrical properties. With its unique advantages such as large band gap, high critical breakdown electric field, high thermal conductivity and high saturation drift speed, it has become a high-voltage, high-power, high-temperature-resistant, high-frequency, anti- It is an ideal semiconductor material for irradiation devices and has broad application prospects in military and civil affairs. Power electronic devices made of silicon carbide materials have become one of the hot devices and frontier research fields in the field of semiconductors. [0003] Silicon carbide MOSFET (Metal-Oxide-SemiconductorField-Effect Transistor, Metal-Oxide-Semiconductor Field-Effect Transistor) has the advantages of low o...

AI Technical Summary

Problems solved by technology

Existing channel self-alignment process is doing N + Before ion implantation in the source region, the P + A metal mask is formed in the contact area as a barrier layer for ion implantation in the P+ region to block N+ implantation. This method introduces a lift-off process, which is incompatible with the existing silicon process. The use of a metal barrier layer in the high-temperature ion implantation process will damage the surface of the device. and ion implanter contamination

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