New Gate CD Control Technology Using CF $_{4}$ Plasma Treatment Following HBr/O $_{2}$ Plasma Treatment Step in Gate Etch Process Using Organic BARC

A new technology of resist trimming in a gate etch process using organic bottom antireflective coating (BARC) for accurate and stable gate critical dimension (CD) control of sub-0.18-mum node technology is presented in this paper. The new method uses an in situ CF
₄
plasma treatment following an HBr/O
₂
plasma treatment step as a part of the gate etch process to achieve a stable gate CD. The new method controls gate CD by trimming the photo resist masking gate line by reducing the effect of etch by-products, the source of CD variation, after etching organic BARC with HBr/O
₂
plasma. It shows the markedly improved gate CD capability over the conventional one using just an HBr/O
₂
plasma treatment for the CD control. We confirm that this new method is very useful and effective for the accurate gate CD control for sub-0.18-mum node metal-oxide semiconductor technology