Method of etching polysilicon layer

摘要

A highly reliable semiconductor IC circuit can be produced by this etching method: A resist layer is formed on a polysilicon layer which is formed on a silicon dioxide layer on a silicon substrate. The resist layer is used as a mask, and silicon oxide layer deposits thereon while polysilicon layer is being etched. Carbon emission out of the resist layer is thus restrained, and thereby a selectivity, an etching speed ratio of polysilicon layer vs. silicon dioxide layer, is substantially raised.