Method for forming CMOS image sensors

US8987033B2 · kind B2 · utility

Assignee

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD. · TW

Inventors

• Ching-Chung Su · Tainan, TW
• Shih-Chang Liu · Guanmiao, TW
• Shih Pei Chou · Tainan, TW
• Chia-Shiung Tsai · Jinshanmian, TW
• Chun-Tsung Kuo · Tainan, TW
• Wen-I Hsu · Tainan, TW
• Yi-Shin Chu · Hsinchu, TW

Key dates

• Filing date: Aug 2, 2011
• Grant date: Mar 24, 2015
• Expiry date: Oct 13, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F39/807

Abstract

A method includes forming a blocking layer over a substrate, and etching the blocking layer to form a trench in the blocking layer. A dielectric layer is formed, wherein the dielectric layer comprises a first portion over the blocking layer, and a second portion in the trench. After the step of forming the dielectric layer, an implantation is performed to implant an impurity into the substrate to form a deep well region. After the implantation, the dielectric layer and the blocking layer are removed.