Semiconductor device

A semiconductor device comprising:

• a first transistor comprising a gate electrode;
• a first insulating layer comprising an opening, wherein the gate electrode of the first transistor is positioned in the opening;
• a second transistor comprising:
• an oxide semiconductor layer on the first insulating layer;
• a first conductive layer and a second conductive layer over the oxide semiconductor layer;
• a second insulating layer over the oxide semiconductor layer, the first conductive layer, and the second conductive layer;
• and
• a gate electrode over the second insulating layer and overlapping with the oxide semiconductor layer
• a switching element electrically connected the second conductive layer;
• and
• a driver circuit electrically connected to the second conductive layer through the switching element,
• wherein the oxide semiconductor layer comprises indium and zinc,
• wherein the first conductive layer is in contact with the surface of the gate electrode of the first transistor and the first insulating layer.

A semiconductor device comprising:

• a first transistor comprising a gate electrode;
• a first insulating layer surrounding the gate electrode of the first transistor;
• a second transistor comprising:
• an oxide semiconductor layer on the first insulating layer;
• a first conductive layer and a second conductive layer over the oxide semiconductor layer;
• a second insulating layer over the oxide semiconductor layer, the first conductive layer, and the second conductive layer;
• and
• a gate electrode over the second insulating layer and overlapping with the oxide semiconductor layer;
• a switching element electrically connected the second conductive layer;
• and
• a driver circuit electrically connected to the second conductive layer through the switching element,
• wherein the oxide semiconductor layer comprise indium and zinc,
• wherein a surface of the gate electrode of the first transistor and a surface of the first insulating layer are included in a same planarized surface, and
• wherein the first conductive layer is in contact with the surface of the gate electrode of the first transistor.

A semiconductor device comprising:

• a first transistor comprising a gate electrode;
• a first insulating layer over the first transistor, wherein the gate electrode of the first transistor is exposed from the first insulating layer;
• a second transistor comprising:
• an oxide semiconductor layer on the first insulating layer;
• a first conductive layer and a second conductive layer over the oxide semiconductor layer;
• a second insulating layer over the oxide semiconductor layer, the first conductive layer, and the second conductive layer;
• and
• a gate electrode over the second insulating layer and overlapping with the oxide semiconductor layer;
• a switching element electrically connected the second conductive layer;
• and
• a driver circuit electrically connected to the second conductive layer through the switching element,
• wherein the oxide semiconductor layer comprises indium and zinc,
• wherein the first conductive layer is in contact with the surface of the gate electrode of the first transistor and the first insulating layer.