Patent ID: 7655947

Claim:
A thin film transistor, comprising: a gate electrode formed on a substrate; a gate insulating film formed on said substrate and gate electrode; an amorphous silicon film formed on said gate insulating film; a drain electrode and a source electrode formed above said amorphous silicon film via a contact layer, and a protection film formed on said amorphous silicon film and said drain electrode and said source electrode; wherein said contact layer is formed at least part where each of said drain electrode and said source electrode are contacted with said amorphous silicon film, and a thickness of said amorphous silicon film measured normal from the boundary between said protection layer and said amorphous silicon film to a top surface of the gate insulating film is thicker than a thickness of said amorphous silicon film measured normal from the boundary between said contact layer and said amorphous silicon film to the top surface of the gate insulating film.