Patent ID: 8373164
Filing Date: 2013-02-12
Classification: H01L

Abstract:
1. A semiconductor device comprising: a gate electrode over a substrate having an insulating surface; an insulating layer over the gate electrode; a source electrode and a drain electrode over the insulating layer; and an oxide semiconductor layer between a side surface of the source electrode and a side surface of the drain electrode, which face each other, so as to overlap with the gate electrode with the insulating layer interposed therebetween, wherein the oxide semiconductor layer is in contact with at least one of the side surface of the source electrode and the side surface of the drain electrode, wherein a first angle between a surface of the substrate and a side surface of a first bottom edge of the source electrode and a second angle between the surface of the substrate and a side surface of a second bottom edge of the drain electrode are each greater than or equal to 20° and less than 90°, wherein the first angle is made to be different from an angle between the surface of the substrate and a side surface of a top edge of the source electrode, and wherein the second angle is made to be different from an angle between the surface of the substrate and a side surface of a top edge of the drain electrode.