Patent ID: 9583587
Date: 2017-02-28
CPC Classifications: H01L

Claim:
1. A method of manufacturing an injection enhanced IGBT (Insulated Gate Bipolar Transistor), comprising steps as follow: providing an N-type substrate; forming a P-type doped layer on the N-type substrate; forming a hard layer on the P-type doped layer; etching the hard layer to form a hard layer having a trench pattern; etching the P-type doped layer to form a trench extending into the N-type substrate; forming an N-type doped layer on a sidewall and a bottom of the trench; removing the hard layer having the trench pattern; performing a drive-in to the P-type dopant of the P-type doped layer and the N-type dopant of the N-type doped layer together, the P-type dopant forming a P-type base region by diffusing, and the N-type dopant forming an N-type buffer layer by diffusing; forming a gate oxide dielectric layer on a surface of the trench; and depositing a polysilicon layer in the trench on which the gate oxide dielectric layer is formed.