SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a transistor which inhibits the occurrence of shape defects when a source electrode layer and a drain electrode layer are formed on an oxide semiconductor in a contacting manner; and form a source electrode layer and a drain electrode layer each having a cross-sectional shape which is unlikely to cause stage cut though a film thickness of a gate insulation film and a film thickness of an oxide semiconductor film which are formed on the source electrode layer and the drain electrode layer are thin.SOLUTION: A semiconductor device manufacturing method comprises: forming an oxide semiconductor film having a crystal structure on an insulation surface; forming an electrode layer in contact with a part of a top face of the oxide semiconductor film; and exposing the oxide semiconductor film to dilute hydrofluoric acid with a concentration of over 0.0001% and not more than 0.25% to reduce a film thickness of an exposed part of the oxide semiconductor film.