Patent ID: 8405149

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