A semiconductor structure is provided. The semiconductor structure includes a substrate, a gate disposed thereon, an insulation layer disposed on the substrate and overlying the gate, a patterned semiconductor layer disposed on the insulation layer, a source and a drain disposed on the patterned semiconductor layer, a protective layer overlying the insulation layer, the source and the boundary of the drain to expose a portion of the drain, and a pixel electrode disposed on the substrate, overlying the protective layer overlying the boundary of the drain, electrically connected to the exposed drain.