Semiconductor device and method for manufacturing the same

A semiconductor device comprising:

• a transistor including:
• a first gate electrode;
• a first insulating layer over the first gate electrode;
• an oxide semiconductor layer over the first insulating layer;
• a second insulating layer over the oxide semiconductor layer, and
• a second gate electrode in contact with the second insulating layer,
• wherein the first gate electrode overlaps with the oxide semiconductor layer with the first insulating layer provided therebetween, and
• wherein the second gate electrode overlaps with the first gate electrode with the oxide semiconductor layer provided therebetween;
• a third insulating layer over the second insulating layer, wherein the third insulating layer is thicker than the second insulating layer;
• a pixel electrode overlapping with the second insulating layer and the third insulating layer;
• and
• a color filter between the second insulating layer and the pixel electrode,
• wherein the second gate electrode overlaps with the oxide semiconductor layer with the second insulating layer interposed therebetween,
• wherein the second gate electrode is separated from the pixel electrode, and
• wherein the second gate electrode and the pixel electrode are formed using the same layer.