Patent ID: 7511709

Claim:
A display device comprising: a plurality of scan lines provided in a first conductive material over a substrate; a plurality of pixels over the substrate; and a scan line driver circuit over the substrate, wherein the scan line driver circuit comprises a shift register and a level shifter, the shift register is connected to a first power supply terminal; the level shifter is connected to a second power supply terminal, each of the pixels and the scan line driver circuit comprises: a gate electrode comprising the first conductive material over the substrate; a gate insulating film over the gate electrode; a lamination film over the substrate; and a second conductive layer over the lamination film, the lamination film comprising: a first semiconductor layer comprising semi-amorphous semiconductor formed over the gate electrode with the gate insulating film interposed therebetween; a second lightly-doped semiconductor layer formed on the first semiconductor layer; a third semiconductor layer having n-type conductivity formed over the first semiconductor layer with the second lightly-doped semiconductor layer interposed at least between the first semiconductor layer and the third semiconductor layer, wherein a voltage of the first power supply terminal is lower than a voltage of the second power supply terminal.