Patent ID: 8324621

Claim:
A semiconductor device comprising: a pixel portion including a first transistor and a driver circuit portion including a second transistor, the pixel portion and the driver circuit portion being provided over a substrate, the first transistor and the second transistor each comprising: a gate electrode layer; a gate insulating layer over the gate electrode layer; an oxide semiconductor layer over the gate insulating layer; a source electrode layer and a drain electrode layer over the oxide semiconductor layer; and an oxide insulating layer over the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, the oxide insulating layer being in contact with the oxide semiconductor layer, a first gate wiring formed from a same layer as the gate electrode layer of the first transistor; a second gate wiring formed from a same layer as the gate electrode layer of the second transistor; and a connection wiring formed from a same layer as the source electrode layer and the drain electrode layer of the second transistor, and in electrical contact with the first gate wiring through the second gate wiring, wherein the gate electrode layer, the source electrode layer, and the drain electrode layer of the first transistor comprise an oxide conductive layer, and wherein the gate electrode layer, the source electrode layer, and the drain electrode layer of the second transistor comprise a metal layer.