Trench gate power MOSFET and manufacturing method thereof

Abstract

The invention discloses a trench gate power MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), which comprises a plurality of trench gates, a body region, a source region and a drain region positioned on the back surface; and each trench gate comprises a gate trench, a gate dielectric layer and a polysilicon gate. The trench gate power MOSFET comprises a plurality of MOSFET unit structures and at least one SBR unit structure, wherein the MOSFET unit structures and the SBR unit structure are connected in parallel. The top of the polysilicon gate of the MOSFET unit structure is connected to a gate composed of a front metal layer through a contact hole, and the top of the source region and the top of the body region are connected to a source composed of a front metal layer through acontact hole. The tops of the polysilicon gate, the source region and the body region of the SBR unit structure are connected to a source electrode consisting of the front metal layer through contactholes. The invention also discloses a manufacturing method of the trench gate power MOSFET. According to the invention, the SBR unit structure can be embedded, so that the recovery rate of the devicecan be improved, and rapid recovery is realized.

Description

technical field [0001] The invention relates to the field of manufacturing semiconductor integrated circuits, in particular to a trench gate power MOSFET. The invention also relates to a method for manufacturing the trench gate power MOSFET. Background technique [0002] Such as figure 1 As shown, it is a schematic structural diagram of an existing trench gate power MOSFET, and the existing trench gate power MOSFET includes a plurality of trench gates. [0003] The trench gate includes a gate trench, a gate dielectric layer 102 and a polysilicon gate 103, the gate dielectric layer 102 is formed on the bottom surface and side surfaces of the gate trench, and the polysilicon gate 103 is filled in the trench in the grid. [0004] The gate trench is formed in the first epitaxial layer 101 of the first conductivity type. [0005] The body region 104 of the second conductivity type is formed in the first epitaxial layer 101, the depth of the polysilicon gate 103 is greater tha...

AI Technical Summary

Problems solved by technology

[0019] figure 1 Existing trench gate power MOSFET shown has slow reverse recovery and cannot achieve fast recovery

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