TRENCH POWER MOSFET AND MANUFACUTRING METHOD THEREOF

摘要

A trench power MOSFET and a manufacturing method thereof are provided. The trench power MOSFET has a buried oxide layer formed in the epitaxial layer, wherein the buried oxide layer is located under a body region for changing a vertical electric field distribution to increase a breakdown voltage of the MOSFET, thereby obtaining a lower on-state resistance.

主权项

1. A trench power MOSEFT, comprising:
a substrate having a first heavily doped region; an epitaxial layer formed above the substrate, wherein the epitaxial layer has a drift region; an oxide layer formed above the drift region; a channel region formed on one side of the oxide layer; a body region formed above the oxide layer and the channel region, wherein the channel region connects the body region and the drift region; a second heavily doped region formed above the body region; and a trench gate structure formed on the side of the second heavily dope region and the body region;wherein the channel region is formed between the trench gate structure and the oxide layer.