Patent ID: 6864150

Claim:
A manufacturing method of shallow trench isolation, comprising: (a) depositing pad-oxide/silicon-nitride on a substrate as a hard mask for etching; (b) depositing a layer of high extinction coefficient silicon oxy-nitride (SiON) on said silicon nitride, then depositing a layer of low extinction coefficient silicon oxy-nitride (SiON) as the anti-reflective coating (ARC); (c) exposing by using a STI mask and developing to form an etching mask of said STI; (d) etching said silicon oxy-nitride (SiON), silicon nitride, pad oxide and said substrate to form a shallow trench; (e) growing an oxide layer on the side wall and the bottom of said shallow trench to remove damage and decrease leakage; (f) depositing an oxide layer on said shallow trench and said silicon nitride to fill said shallow trench; (g) planarizing by chemical mechanical polishing (CMP).