SEMICONDUCTOR DEVICE, METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE AND ETCHANT USED FOR SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device using a copper-containing metal film for wirings, signal lines, or the like in a transistor using an oxide semiconductor film, to provide a novel semiconductor device having a good shape of a copper-containing metal film in a transistor using an oxide semiconductor film, or to provide an etchant which can be used in a transistor using an oxide semiconductor film.SOLUTION: A method for manufacturing a semiconductor device comprises: a step of forming a first conductive film on a substrate; a step of forming an insulation film on the first conductive film; a step of forming an oxide semiconductor film at a position which overlaps the first conductive film on the insulation film; a step of forming a film of a second conductive film including a metal film whose main component is molybdenum and a metal film whose main component is copper on the oxide semiconductor film; and a step of etching the second conductive film by an etchant. In the step of etching the second conductive film by the etchant, the oxide semiconductor film is used as an etching stopper film.