Patent ID: 9040980
Filing Date: 2015-05-26
Classification: H01L

Abstract:
1. A transistor comprising: a source electrode layer; an oxide semiconductor layer in contact with the source electrode layer; a drain electrode layer in contact with the oxide semiconductor layer; a first gate electrode layer, wherein part of the first gate electrode layer overlaps with the source electrode layer, the drain electrode layer, and the oxide semiconductor layer; a second gate electrode layer, wherein part of the second gate electrode layer overlaps with the source electrode layer, the drain electrode layer, and the oxide semiconductor layer; a first gate insulating layer in contact with a surface of the first gate electrode layer; and a second gate insulating layer in contact with a surface of the second gate electrode layer, wherein the first gate insulating layer on a bottom surface side of the first gate electrode layer is in contact with the source electrode layer, wherein the second gate insulating layer on a bottom surface side of the second gate electrode layer is in contact with the source electrode layer, wherein the first gate insulating layer on an upper surface side of the first gate electrode layer is in contact with the oxide semiconductor layer, and wherein the second gate insulating layer on an upper surface side of the second gate electrode layer is in contact with the oxide semiconductor layer, wherein the first gate electrode layer has a first comb-shaped electrode and the second gate electrode layer has a second comb-shaped electrode, wherein first side surfaces of the first comb-shaped electrode and second side surfaces of the second comb-shaped electrode have tapered shapes, wherein one of the first side surfaces and one of the second side surfaces are opposed to each other, and wherein the oxide semiconductor layer and a part of the drain electrode layer is interposed between the one of the first side surfaces of the first comb-shaped electrode and the one of the second side surfaces of the second comb-shaped electrode.