Patent ID: 8101442

Claim:
A method for manufacturing an EL display device comprising the steps of: forming a thin film transistor comprising the steps of: stacking a first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film sequentially; forming a first resist mask over the second conductive film; first etching the first insulating film, the semiconductor film, the impurity semiconductor film, and the second conductive film using the first resist mask to expose at least a surface of the first conductive film; second etching a portion of the first conductive film to form a gate electrode layer in such a manner that a width of the gate electrode layer is narrower than a width of the first insulating film; forming a second resist mask over the second conductive film; and third etching the second conductive film, the impurity semiconductor film, and a part of the semiconductor film using the second resist mask to form a source and drain electrode layer, a source and drain region layer, and a semiconductor layer; removing the second resist mask; forming a second insulating film to cover the thin film transistor; forming an opening in the second insulating film so as to expose a part of the source and drain electrode layer; forming a first pixel electrode selectively over the opening and the second insulating film; forming an EL layer over the first pixel electrode; and forming a second pixel electrode over the EL layer.