Sidewall oxidation behavior of dichlorosilane-based W-polycide gate

We studied the sidewall oxidation behavior of dichlorosilane-based WSix/P-d oped Si stack gate electrode and compared to that of monosilane-based WSix . WSix was known to be abnormally oxidized during reoxidation after gate st ack patterning, resulting in deformation of the sidewall profile of gate el ectrode. We found that low temperature oxide for mask of gate patterning wa s effective to prevent the abnormal oxidation, Preannealing at temperature higher than 800 degreesC was also found to effectively suppress the abnorma l oxidation of crystalline WSix. (C) 2001 American Vacuum Society.