METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a semiconductor device is provided to reduce lack of oxygen by forming a sidewall insulating layer around a second oxide semiconductor. CONSTITUTION: A fourth etching mask is formed on a second conductive film. A second conductive layer(120) is formed by processing a second conductive film using the fourth etching mask. The fourth etching mask is removed. The ion implantation is performed on first oxide semiconductor layer using the second conductive layer as a mask. A second oxide semiconductor layer(124) including source and drain regions is formed.