Semiconductor device and display device
According to one embodiment, a semiconductor device includes a first gate electrode formed integrally with a scanning line, an oxide semiconductor layer, first and second signal lines which are in contact with the oxide semiconductor layer, and a second gate electrode provided so as to face the first gate electrode across the oxide semiconductor layer therebetween and connected to the first gate electrode. The second gate electrode is provided between the first signal line and the second signal line and does not overlap the first signal line or the second signal line.
1 . A semiconductor device comprising:
a first gate electrode formed integrally with a scanning line;
a first insulating layer covering the first gate electrode;
an oxide semiconductor layer above the first gate electrode with the first insulating layer interposed therebetween;
a first signal line and a second signal line which are in direct contact with the oxide semiconductor layer, the first signal line being a conductive signal line in direct contact with a source region of the oxide semiconductor layer, the second signal line being a conductive signal line in direct contact with a drain region of the oxide semiconductor layer;
a second insulating layer entirely covering the oxide semiconductor layer, the first signal line, and the second signal line; and
a second gate electrode provided on the second insulating layer so as to face the first gate electrode across the oxide semiconductor layer therebetween, and connected to the first gate electrode, wherein
the second gate electrode is provided between the first signal line and the second signal line and does not overlap the first signal line or the second signal line.
2 . The semiconductor device according to claim 1 , wherein
the second gate electrode is formed of a light-shielding conductive material.
3 . The semiconductor device according to claim 1 , wherein the oxide semiconductor layer comprises a plurality of oxide semiconductor layers.
4 . The semiconductor device according to claim 1 , wherein the oxide semiconductor layer is a single oxide semiconductor layer.
5 . A display device comprising:
a pixel;
the semiconductor device according to claim 1 and provided in the pixel, wherein the pixel is provided at an intersection of the first signal line and the scanning line;
a pixel electrode connected to the second signal line; and
a transparent electrode overlapping the scanning line and the first signal line.
6 . The display device according to claim 5 , wherein
the transparent electrode does not overlap the second gate electrode.
7 . A semiconductor device comprising:
a first gate electrode formed integrally with a scanning line;
a first insulating layer covering the first gate electrode;
an oxide semiconductor layer above the first gate electrode with the first insulating layer interposed therebetween;
a first signal line and a second signal line which are in direct contact with the oxide semiconductor layer, the first signal line being a conductive signal line in direct contact with a source region of the oxide semiconductor layer, the second signal line being a conductive signal line in direct contact with a drain region of the oxide semiconductor layer;
a second insulating layer entirely covering the oxide semiconductor layer, the first signal line, and the second signal line; and
a second gate electrode provided on the second insulating layer so as to face the first gate electrode across the oxide semiconductor layer therebetween and connected to the first gate electrode, wherein
the second gate electrode is provided between the first signal line and the second signal line and does not overlap the first signal line or the second signal line, and
the second gate electrode includes a first section, a second section, and a connection electrode provided in a layer different from a layer of the first section and the second section.
8 . The semiconductor device according to claim 7 , wherein
the first section, the second section and the connection electrode are formed of a light-shielding conductive material.
9 . The semiconductor device according to claim 8 , wherein
an area in which the first section and the connection electrode are connected to each other does not overlap the oxide semiconductor layer.
10 . The semiconductor device according to claim 8 , wherein
an area in which the first section and the connection electrode are connected to each other overlaps the oxide semiconductor layer.
11 . The semiconductor device according to claim 7 , wherein
the first section and the second section are formed of a light-shielding conductive material, and
the connection electrode is formed of a transparent conductive material.
12 . The semiconductor device according to claim 11 , wherein
an area in which the first section and the connection electrode are connected to each other does not overlap the oxide semiconductor layer.
13 . The semiconductor device according to claim 11 , wherein
an area in which the first section and the connection electrode are connected to each other overlaps the oxide semiconductor layer.
14 . The semiconductor device according to claim 7 , wherein the semiconductor layer comprises a plurality of oxide semiconductor layers.
15 . The semiconductor device according to claim 7 , wherein the oxide semiconductor layer is a single oxide semiconductor layer.
16 . A display device comprising:
a pixel;
the semiconductor device according to claim 7 and provided in the pixel, wherein the pixel is provided at an intersection of the first signal line and the scanning line;
a pixel electrode connected to the second signal line; and
a transparent electrode overlapping the scanning line and the first signal line.
17 . The display device according to claim 16 , wherein
the transparent electrode does not overlap the second gate electrode.