Semiconductor device

A semiconductor device comprising:

• a substrate;
• a first insulating film over the substrate;
• a second insulating film over the first insulating film, the second insulating film being an inorganic insulating film;
• a third insulating film over the second insulating film, the third insulating film being an organic insulating film;
• a transistor in a pixel portion, the transistor comprising:
• a first gate electrode over the substrate;
• the first insulating film over the first gate electrode;
• an oxide semiconductor layer over the first insulating film and overlapping the first gate electrode;
• a source electrode and a drain electrode each in direct contact with the oxide semiconductor layer;
• the second insulating film over the oxide semiconductor layer, the source electrode, and the drain electrode;
• and
• a second gate electrode overlapping the oxide semiconductor layer and the first gate electrode, with the second insulating film between the second gate electrode and the oxide semiconductor layer;
• in the third insulating film, a first opening overlapping the oxide semiconductor layer and a second opening overlapping one of the source electrode and the drain electrode;
• and
• a pixel electrode over the third insulating film, in the second opening, and in direct contact with the one of the source electrode and the drain electrode in a third opening formed in the second insulating film, the third opening overlapping with the second opening,
• wherein the second gate electrode is in the first opening, and
• wherein the second gate electrode and the pixel electrode define respectively a first portion and a second portion of a same conductive film.