Trench gate super-junction MOSFET

Abstract

The invention discloses a trench gate super-junction MOSFET. The trench gates of the device are formed at the tops of interfaces of the P-type columns and the N-type columns of a super-junction structure and span the corresponding interfaces; the trench regions composed of P wells are formed at the tops of the N-type columns; the source regions are formed on the surface of the trench regions; the tops of the trench regions and the source regions are simultaneously connected to the source electrode composed of a right-side metal layer through the same contact holes; the tops of the P-type columns are connected to the source electrode via contact holes; a parasitic transistor consists of a source region, a trench region, and a drift region at the top of each N-type column; and the trench gates are set into a structure spanning the interfaces of the P-type columns and the N-type columns, so that the side parts of the trench gates in the P-type columns form an avalanche current path away from the parasitic transistor when the device reverse avalanche breaks down, and the EAS capability of the device is improved.

Description

technical field [0001] The invention relates to a semiconductor integrated circuit, in particular to a trench gate super junction MOSFET. Background technique [0002] The super-junction MOSFET adopts a new voltage-resistant layer structure, and uses a series of superjunction structures composed of alternately arranged semiconductor P-type thin layers and N-type thin layers to combine P-type thin layers and N-type thin layers at lower voltages in the off state. The N-type thin layer is depleted to achieve mutual compensation of charges, so that the P-type thin layer and N-type thin layer can achieve high breakdown voltage under high doping concentration, thereby obtaining low on-resistance and high reverse breakdown at the same time Voltage (BV), that is, super junction MOSFET is to use PN, that is, P-type thin layer and N-type thin layer charge balance to reduce the surface electric field (Resurf) technology in the body to improve the BV of the device while maintaining a sm...

AI Technical Summary

Problems solved by technology

[0003] In the application of superjunction devices, its single-pulse avalanche breakdown energy (EAS) capability is one of the key performances of the robustness of the device, which is very important. Devices with poor EAS capabilities are often prone to failure in use. In severe cases, even a bombing phenomenon

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