METHOD FOR FABRICATING TRENCH DMOS TRANSISTOR

摘要

A method for fabricating trench DMOS transistor includes: forming an oxide layer(104) and a barrier layer(106) with photolithography layout sequentially on a semiconductor substrate(100); etching the oxide layer(104) and the semiconductor substrate(100) with the barrier layer(106) as a mask to form a trench(110); forming a gate oxide layer(112) on the inner wall of the trench(110); forming a polysilicon layer on the barrier layer(106), filling up the trench(110); etching back the polysilicon layer with the barrier layer mask to remove the polysilicon layer on the barrier layer(106) to form a trench gate(114); removing the barrier layer(106) and the oxide layer(104); implanting ions into the semiconductor substrate(100) on both sides of the trench gate(114) to form a diffusion layer(115); coating a photoresist layer(116) on the diffusion layer(115) and defining a source/drain layout thereon; implanting ions(117) into the diffusion layer(115) based on the source/drain layout with the photoresist layer(116) mask to form the source/drain(118); forming sidewalls(120) on both the sides of the trench gate(114) after removing the photoresist layer(116); and forming a metal silicide layer(122) on the diffusion layer(115) and the trench gate(114). Effective result is achieved with lower cost and improved efficiency of fabrication.