Patent ID: 8378343

Claim:
A semiconductor device comprising: a driver circuit comprising a first transistor and a pixel portion comprising a second transistor over a substrate; the first transistor comprising: a first gate electrode layer over the substrate; a gate insulating layer over the first gate electrode layer; a first oxide semiconductor layer comprising a first channel formation region over the first gate electrode layer with the gate insulating layer interposed therebetween; a first source electrode layer and a first drain electrode layer over the first oxide semiconductor layer; and an oxide insulating layer over the first source electrode layer and the first drain electrode layer; the second transistor comprising: a second gate electrode layer over the substrate; the gate insulating layer over the second gate electrode layer; a second oxide semiconductor layer over the second gate electrode layer with the gate insulating layer interposed therebetween; a channel protective layer over the second gate electrode layer with the second oxide semiconductor layer interposed therebetween; and a second source electrode layer and a second drain electrode layer over the second oxide semiconductor layer, wherein the oxide insulating layer is in contact with the first channel formation region, and wherein each of the second gate electrode layer, the gate insulating layer, the second oxide semiconductor layer, the channel protective layer, the second source electrode layer, and the second drain electrode layer has a light-transmitting property.