Patent ID: 8405092

Claim:
A display device comprising: a pixel portion comprising a plurality of pixels over an insulating surface, each of the plurality of pixels comprising: a light-emitting element; a switching element for controlling on/off of a current control element; and the current control element for controlling a current of the light-emitting element, the current control element comprising: a first gate electrode and a second gate electrode formed apart from each other over the insulating surface; a first oxide semiconductor film comprising a region overlapping with the first gate electrode with a gate insulating film interposed therebetween, a region overlapping with the second gate electrode with the gate insulating film interposed therebetween, and a region overlapping with neither the first gate electrode nor the second gate electrode; one of a first source electrode and a first drain electrode overlapping with a part of the first gate electrode and a part of the first oxide semiconductor film; the other of the first source electrode and the first drain electrode overlapping with a part of the second gate electrode and a part of the first oxide semiconductor film; and an insulating film covering the gate insulating film, the first gate electrode, the second gate electrode, the first oxide semiconductor film, the first source electrode, and the first drain electrode, the insulating film being in direct contact with the first oxide semiconductor film, and a driver circuit for driving the pixel portion over the insulating surface, the driver circuit comprising a transistor comprising: a third gate electrode over the insulating surface; a second oxide semiconductor film overlapping with the third gate electrode with the gate insulating film interposed therebetween; a second source electrode overlapping with a part of the third gate electrode and a part of the second oxide semiconductor film and a second drain electrode overlapping with a part of the third gate electrode and a part of the second oxide semiconductor film; and the insulating film covering the gate insulating film, the third gate electrode, the second oxide semiconductor film, the second source electrode, and the second drain electrode, the insulating film being in direct contact with the second oxide semiconductor film.