Patent ID: 7485898

Claim:
A semiconductor device comprising: a pixel comprising: a thin film transistor comprising: a semiconductor film having a pair of impurity regions and a channel region interposed therebetween, and a pair of lightly doped regions between the channel region and the pair of impurity regions, wherein each of the pair of lightly doped regions includes a fi and a second portion; a gate insulating film formed over the semiconductor film; a gate electrode formed over the channel region with the gate insulating film interposed therebetween, wherein the gate electrode comprises a first conductive layer formed on the gate insulating film, and a second conductive layer formed on top and side surfaces of the first conductive layer, wherein the second conductive layer extends beyond side edges of the first conductive layer, and contacts with the gate insulating film, wherein an extended portion of the second conductive layer overlaps the first portion of each of the pair of lightly doped regions, and wherein the gate electrode does not overlap the second portion of each of the pair of lightly doped regions, a planarizing film formed over the thin film transistor; a pixel electrode formed over the planarizing film, and electrically connected to one of the pair of impurity regions; and a light emitting layer over the pixel electrode.