Patent ID: 8716708

Claim:
A semiconductor device comprising: a gate electrode layer over an insulating surface; a gate insulating film over the gate electrode layer; an oxide semiconductor film including a channel formation region over the gate insulating film; an insulating layer over and in contact with the oxide semiconductor film; a source electrode layer having an end portion over the insulating layer; and a drain electrode layer having an end portion over the insulating layer, wherein the end portion of the source electrode layer and the end portion of the drain electrode layer overlap with the channel formation region, wherein the insulating layer, the source electrode layer, and the drain electrode layer are in direct contact with a first surface of the oxide semiconductor film, wherein an angle between a side surface of an end portion of the insulating layer and the insulating surface is smaller than or equal to 60°, and wherein a thickness of the insulating layer is less than or equal to 0.3 μm.