SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a transistor excellent in electrical characteristics.SOLUTION: A semiconductor device manufacturing method comprises: preparing a substrate having an insulating surface; depositing laminated films including a first oxide semiconductor layer and a second oxide semiconductor layer on the substrate; forming a mask layer on a part of the laminated films and subsequently performing a dry etching treatment thereby to remove the laminated films leaving a region where the mask layer is provided and to form a reaction product on a lateral face of the remaining laminated films; removing the mask layer and subsequently removing the reaction product by a wet etching treatment to form a source electrode and a drain electrode on the laminated films; and forming a third oxide semiconductor layer, a gate insulation film, and a gate electrode by sequential lamination on the laminated films, on the source electrode and on the drain electrode.