Patent ID: 8654272

Claim:
A semiconductor device comprising: a substrate; a driver circuit portion including a first transistor over the substrate; and a pixel portion including a second transistor and a pixel electrode layer over the substrate, wherein the first transistor comprises a first electrode layer; a first insulating layer over the first electrode layer; a first oxide semiconductor layer over the first insulating layer; a second electrode layer and a third electrode layer over the first oxide semiconductor layer; a second insulating layer over the second electrode layer, the third electrode layer, and the first oxide semiconductor layer; and a conductive layer over the second insulating layer, wherein the conductive layer and the first electrode layer are overlapped with each other with the first insulating layer, the first oxide semiconductor layer, and the second insulating layer interposed therebetween, wherein the second transistor comprises: a fourth electrode layer; the first insulating layer over the fourth electrode layer; a second oxide semiconductor layer over the first insulating layer; a fifth electrode layer and a sixth electrode layer over the second oxide semiconductor layer; and the second insulating layer over the fifth electrode layer, the sixth electrode layer, and the second oxide semiconductor layer, wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes a portion which is in contact with the second insulating layer, the portion being in an oxygen-excess state, and wherein the pixel electrode layer is electrically connected to the second transistor.