DRY ETCHING METHOD USING ALUMINUM ALLOY FILM

摘要

PURPOSE:To prevent the local corrosion of the wiring material right under a resist in a titled method for an Al alloy film contg. Cu or In, by depositing beforehand a film of Al or an Al alloy contg. no Cu and In on said film. CONSTITUTION:An Al-Si-Cu alloy film 3 is deposited on an insulation film 2 provided on an Si substrate 1, and a pure Al film 6 of about 1,000Angstrom thickness is deposited thereon. A resist mask 5 having a wiring pattern is formed thereon and the part except the region for the wiring is dry-etched by using a gaseous mixture of CCl4-Cl2 as an etching gas. The resist 5 and the film 3 in this case are not in direct contact with each other as the film 6 is interposed between the same. The contact of the residue contg. Cl stuck on the resist 5 with the film 3 is thus prevented by the film 6 and since the corrosion of the film 6 is substantially slow, the corrosion is prevented by the treatment after the etching.