Patent ID: 9082863
Filing Date: 2015-07-14
Classification: H01L

Abstract:
1. A semiconductor device comprising: a gate electrode layer; an oxide semiconductor stacked film overlapping with the gate electrode layer with a first insulating film therebetween; a source electrode layer and a drain electrode layer electrically connected to the oxide semiconductor stacked film; and a second insulating film overlapping with the oxide semiconductor stacked film, wherein the oxide semiconductor stacked film includes a first oxide semiconductor layer, a second oxide semiconductor layer, and a third oxide semiconductor layer which are sequentially stacked, wherein the third oxide semiconductor layer includes a first region in contact with a top surface of the second oxide semiconductor layer and a second region in contact with top surfaces of the source electrode layer and the drain electrode layer, wherein the second oxide semiconductor layer includes a first crystalline structure whose c-axis is aligned in a direction parallel to a normal vector of a surface of the second oxide semiconductor layer, and wherein the third oxide semiconductor layer includes a second crystalline structure whose c-axis is aligned in a direction parallel to a normal vector of a surface of the third oxide semiconductor layer.