Patent ID: 7381991

Claim:
A semiconductor device comprising: a first n-channel thin film transistors and a second thin film transistor in one pixel, wherein a gate electrode of said first and second thin film transistors consist essentially of one layer formed in contact with a gate insulating film; wherein a semiconductor layer of said n-channel thin film transistors comprises a channel formation region, a first impurity region of one conductivity type, and a second impurity region of one conductivity type that is sandwiched between said channel formation region and said first impurity region and is contact with said channel formation region, wherein a part of said second impurity region of said one conductivity type overlaps with said gate electrode; and wherein a semiconductor layer of said second thin films transistor comprises a channel formation region, a first impurity region of one conductivity type and a second impurity region of said one conductivity type that is sandwiched between said channel formation region and said first impurity region and is in contact with said channel formation region, wherein only one side of said second impurity region of said one conductivity type overlaps with said gate electrode.