Patent ID: 8823004

Claim:
A display device comprising: a transistor comprising: a gate electrode; a first insulating film over the gate electrode; a semiconductor film over the first insulating film, the semiconductor film comprising a first portion, a second portion, and a recessed portion interposed between the first portion and the second portion, wherein a thickness of the first portion is larger than a thickness of the recessed portion and a thickness of the second portion is larger than the thickness of the recessed portion; a source electrode over and electrically connected to the semiconductor film; and a drain electrode over and electrically connected to the semiconductor film; a pixel electrode over and electrically connected to one of the source electrode and the drain electrode, a second insulating film over the semiconductor film, wherein the second insulating film comprises a region located between the source electrode and the drain electrode, and the region is in contact with a top surface of the first portion, a top surface of the second portion and a top surface of the recessed Portion, wherein the gate electrode overlaps with the recessed portion, and wherein a gap between the source electrode and the drain electrode is larger than a width of the recessed portion.