65nm poly gate etch challenges and solutions

This paper presents an overview of 65 nm poly gate fabrication challenges emerged during the device performance & yield enhancement on 300 mm wafer. The proposed solutions hinge on the improvement of some critical process parameters in 65 nm gate etch such as, critical dimension uniformity (CDU), through-pitch etch bias (TPEB), line width roughness (LWR) and poly gate profile. More than 7% yield enhancement and improved Vmin (the minimum voltage at which the addressed device function correctly) distribution have been obtained with improved CDU&TPEB.