SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide good electric characteristics to a semiconductor device using an oxide semiconductor; or provide a semiconductor device having high reliability.SOLUTION: A semiconductor device manufacturing method comprises: a process of forming an oxide semiconductor layer on an insulating surface; a process of forming a source electrode and a drain electrode on the oxide semiconductor layer; a process of depositing an insulation film and a conductive film in this order on the oxide semiconductor layer, the source electrode and the drain electrode; a process of forming a gate electrode and a gate insulation layer by etching a part of the conductive film and insulation film, and forming a first coating layer including constituent element of the source electrode and the drain electrode in contact with a lateral face of the gate insulation layer by etching a part of upper parts of the source electrode and drain electrode; a process of forming a second coating layer by oxidizing the first coating layer; and a process of depositing an oxide-containing protective insulation layer on the second coating layer.