Method of forming low dielectric silicon oxynitride spacer films highly selective to etchants

摘要

A method of depositing a silicon oxynitride spacer film on a gate stack in a semiconductor device involves contacting the gate stack with bistertiarybutylaminosilane (BTBAS), at least one nitrogen containing compound and oxygen (O2). The deposition is controlled to provide a wet etch rate for the deposited spacer film that is within the range of about 25 Angstroms per minute to less than or equal to about 1 Angstrom.