Patent ID: 7414288

Claim:
A semiconductor device comprising at least a display device, said display device comprising: a substrate having an insulating surface; a semiconductor layer over the substrate, said semiconductor layer including at least a channel region; a first insulating film comprising silicon oxide formed over the semiconductor layer; a second insulating film comprising silicon nitride formed over the first insulating film; a gate electrode located over the channel region of the semiconductor layer with the first insulating film and the second insulating film interposed therebetween; a third insulating film comprising silicon nitride formed over the semiconductor layer, the first and second insulating films and the gate electrode; and a pixel electrode formed over said third insulating film wherein said pixel electrode is electrically connected to the semiconductor layer, wherein said second insulating film extends beyond edges of the gate electrode; wherein said first insulating film extends beyond edges of the second insulating film, and wherein said third insulating film is in direct contact with an upper surface of an extending portion of the first insulating film and an upper surface of an extending portion of the second insulating film.