Etching of polysilicon in inductively coupled Cl sub(2) and HBr discharges: I. Experimental characterization of polysilicon profiles

The etching of photoresist and oxide masked polysilicon samples was done in inductively coupled HBr and Cl sub(2) dicharges and experimental characterization of polysilicon profiles was done. The important features exhibited in the profiles included the greater polysilicon-to-photoresist selectivity exhibited by HBr over Cl sub(2), the increased sidewall deposition associated with photoresist over oxide masks and the variation of photoresist facet angle associated with product deposition. The lack of microtrenching was also observed for the HBr etching.