Patent ID: 8153337

Claim:
A photomask for fabricating a thin film transistor, comprising: a transparent substrate having a U-shaped channel-forming region and a rectangular channel-forming region adjacent thereto; a translucent layer disposed on the transparent substrate and covering the U-shaped and rectangular channel-forming regions; a first light-shielding layer and a second light-shielding layer disposed on the translucent layer and located at the outer and inner sides of the U-shaped channel-forming region, respectively, to serve as a pair of first source/drain-forming regions; a third light-shielding layer and a fourth light-shielding layer disposed on the translucent layer and located at opposite sides of the rectangular channel-forming region, respectively, to serve as a pair of second source/drain-forming regions, wherein an end of the third light-shielding layer extends to the first light-shielding layer; and a plurality of first light-shielding islands disposed on the translucent layer and located within the rectangular channel-forming region.