Method of manufacturing semiconductor device

摘要

A method of etching a semiconductor device preventing tapering of a gate electrode edge includes a main etching of an electrode or wiring material supported by a dielectric film at a semiconductor substrate surface to expose the dielectric film. After the main etching step, residues of the electrode or the wiring material by sequentially etching utilizing a first gas mixture including a halogen-containing gas and an additive gas suppressing etching of the dielectric film by the halogen-containing gas, and in a second gas mixture gas including the halogen-containing gas and the additive gas and having the additive gas amount in a larger concentration than the first gas mixture.