Patent ID: 7166899
Filing Date: 2007-01-23
Classification: G02B,G02F,H01L

Abstract:
1. A semiconductor device comprising: a semiconductor layer formed over a substrate, the semiconductor layer including at least a channel region, and source and drain regions; a gate electrode located over the channel region of the semiconductor layer; at least first and second insulating films, each comprising silicon oxynitride interposed between the gate electrode and the channel region of the semiconductor layer; and a third insulating film formed over the semiconductor layer, the first and second insulating films and the gate electrode; wherein the second insulating film has a different composition from the first insulating film and is formed over the first insulating film, wherein the gate electrode comprises at least a first layer and a second layer, wherein the third insulating film is in contact with a part of the first insulating film, and wherein the gate electrode has at least a tapered portion.