Silicon carbide mosfet device and manufacturing method thereof

Abstract

The invention discloses a self-aligned silicon carbide metal-oxide-semiconductor field-effect-transistor (MOSFET) device with an optimized P<+> region and a fabrication method of the self-aligned silicon carbide MOSFET device. The self-aligned silicon carbide MOSFET device is formed by connecting a plurality of same cells in parallel, and the cells of the silicon carbide MOSFET device are uniformly arranged. Each cell of the silicon carbide MOSFET device comprises two sources, a grid, a grid oxide layer, two N<+> source regions, two P<+> contact regions, two P pits, an N<-> drift layer, a buffer layer, an N<+> substrate, a drain and an isolation dielectric layer. By optimizing the P<+> region, favorable source ohmic contact is formed, the on resistance is reduced, meanwhile, the source and the P pits are in short connection, parasitic negative-positive-negative (PNP) and a parasitic transistor effect of PiN are prevented, the conduction property and the breakdown property of the device can be compatible, and the device can be used in a high-voltage and high-frequency silicon carbide MOSFET device. A self-aligned fabrication method is adopted by the invention, the process is simplified, the channel size is accurately controlled, and a transverse or longitudinal power MOSFET can be fabricated.

Description

technical field [0001] The invention relates to a self-aligned silicon carbide MOSFET device and its manufacturing process, in particular to an optimized P + Area self-aligned silicon carbide MOSFET devices and methods of fabrication thereof. Background technique [0002] Silicon carbide material has excellent physical and electrical properties. With its unique advantages such as wide band gap, high thermal conductivity, large saturation drift velocity and high critical breakdown electric field, it has become a high-power, high-frequency, high-voltage It is an ideal semiconductor material for high temperature resistant and radiation resistant devices, and has broad application prospects in military and civil affairs. Silicon carbide MOSFET devices have the advantages of fast switching speed and small on-resistance, and can achieve a high breakdown voltage level at a small drift layer thickness, reduce the volume of the power switch module, and reduce energy consumption. , ...

AI Technical Summary

Problems solved by technology

This method has strict requirements on the thermal oxidation process of polysilicon, and the size of the formed channel cannot be precisely controlled

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