Patent ID: 6900460
Filing Date: 2005-05-31
Classification: G02F,H01L

Abstract:
1. A semiconductor device comprising at least a pixel portion and a driving circuit portion, the pixel portion having at least one p-channel TFT and the driving circuit portion having at least an n-channel TFT and a p-channel TFT, each of the at least one n-channel TFT and the p-channel TFTs comprising: a semiconductor layer formed on an insulating surface; an insulating film formed on the semiconductor layer; and a gate electrode formed on the insulating film, wherein the gate electrode of the n-channel TFT of the driving circuit portion has a laminate structure with a first conductive layer as a lower layer and a second conductive layer as an upper layer, the first conductive layer having a first width and the second conductive layer having a second width that is narrower than the first width, and wherein the gate electrode of the p-channel TFT of at least the pixel portion has a laminate structure comprising a third conductive layer and a fourth conductive layer over the third conductive layer, wherein a first angle formed by a bottom surface and a side surface of the third conductive layer is larger than a second angle formed by a bottom surface and a side surface of the fourth conductive layer.