Patent ID: 8497211

Claim:
A method of depositing a phosphosilicate glass (PSG) film on a substrate disposed in a substrate processing chamber, the method comprising: depositing a first portion of the PSG film over the substrate and within a gap using a high-density plasma process; etching back a portion of the first portion of the PSG film, wherein etching back the portion comprises: flowing a halogen precursor to the substrate processing chamber; forming a high-density plasma from the halogen precursor; and terminating flowing the halogen precursor after the portion has been etched back; flowing a halogen scavenger to the substrate processing chamber to react with residual halogen in the substrate processing chamber; thereafter, exposing the first portion of the PSG film to a phosphorus-containing gas to provide a substantially uniform phosphorus concentration throughout the first portion of the PSG film; and thereafter, depositing a second portion of the PSG film over the first portion of the PSG film and within the gap using a high-density plasma process.