Selective formation of hydrogen rich PECVD silicon nitride for improved NMOS transistor performance

US6372569B1 · kind B1 · utility

Assignee

• Chartered Semiconductor Manufacturing LTD · SG

Inventors

• Yong Meng Lee · Singapore, SG
• Gao Feng · Singapore, SG
• Yunqzang Zhang · Singapore, SG
• Ravi Sundaresan · San Jose, US

Key dates

• Filing date: Jan 18, 2000
• Grant date: Apr 16, 2002
• Expiry date: Jan 18, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D84/038

Abstract

A method of selective formation of SiN layer in a semiconductor device comprising the following steps. A semiconductor structure having at least one PMOS transistor and one NMOS transistor formed therein is provided. The PMOS and NMOS transistors each have source/drain regions, a gate, and salicide contact regions. An undoped silicate glass (USG) layer is deposited over the semiconductor structure and the PMOS and NMOS transistors. An H2-rich PECVD silicon nitride layer is deposited over the undoped silicate glass layer and over the PMOS and NMOS transistors. The H2-rich PECVD silicon nitride layer is patterned, etched, and removed from over the PMOS transistor. An inter-level dielectric (ILD) layer is formed over the structure. The ILD layer is densified whereby hydrogen diffuses from the H2-rich PECVD silicon nitride layer overlying the NMOS transistor into the source/drain of the NMOS transistor.