Chamber cleaning process selection for installed-base CVD tools

This study presents a c-C
₄
F
₈
based chamber cleaning chemistry as an opportunity that has both process and ESH benefits with minimal cost and process modifications. c-C
₄
F
₈
was identified based on a balanced approach. The benefits of c-C
₄
F
₈
compared to the C
₃
F
₈
cleaning process were estimated to justify this work. Several factors related to cost and SHE were evaluated. Some issues pertaining to the cleaning gas delivery were considered. Previously optimized c-C
₄
F
₈
recipes were used to minimize the c-C
⁴
F
₈
recipe development work. FTIR and optical emission endpoint detector were used to verify the completion of chamber cleaning, and the reductions in PFC emissions. The results indicated that the c-C
₄
F
₈
cleaning process reduced PFC emission by 57%, compared to our current C
₃
F
₈
cleaning process. Reduced gas consumption also enabled 20% cost saving on cleaning gas. This work demonstrated a low cost and low effort approach to reduce PFC emissions in installed-base tools