METHOD FOR MANUFACTURING TRANSISTOR

摘要

To provide a method for manufacturing a transistor which has little variation in characteristics and favorable electric characteristics. A gate insulating film is formed over a gate electrode; a semiconductor layer including a microcrystalline semiconductor is formed over the gate insulating film; an impurity semiconductor layer is formed over the semiconductor layer; a mask is formed over the impurity semiconductor layer, and then the semiconductor layer and the impurity semiconductor layer are etched with use of the mask to form a semiconductor stacked body; the mask is removed and then the semiconductor stacked body is exposed to plasma generated in an atmosphere containing a rare gas to form a barrier region on a side surface of the semiconductor stacked body; and a wiring over the impurity semiconductor layer of the semiconductor stacked body is formed.