Imaging device and electronic device

1. A semiconductor device comprising:

a first layer; and

a second layer,

wherein the first layer comprises a first insulating layer, a second insulating layer, and a first transistor comprising a channel formation region in an oxide semiconductor layer,

wherein the first transistor is provided between the first insulating layer and the second insulating layer,

wherein the first transistor comprises a first conductive layer in contact with the oxide semiconductor layer,

wherein the second layer comprises a photodiode, and

wherein the first conductive layer is electrically connected to one of a cathode and an anode of the photodiode via a first conductor that penetrates the first insulating layer, the first conductive layer, and the second insulating layer.

2. The semiconductor device according to claim 1 , wherein the photodiode is provided in a single crystal silicon substrate.

3. The semiconductor device according to claim 1 , further comprising a third layer,

wherein the third layer comprises a third insulating layer, a fourth insulating layer, and a second transistor comprising silicon in a channel formation region,

wherein a top surface of a gate of the first transistor faces a top surface of a gate of the second transistor,

wherein a second conductive layer is embedded in the third insulating layer,

wherein a source, a drain, or a gate of the second transistor is electrically connected to the second conductive layer via a second conductor that penetrates the fourth insulating layer,

wherein a third conductive layer is provided on a light-receiving surface side of the photodiode in the single crystal silicon substrate, and

wherein the second conductive layer is electrically connected to the third conductive layer via a third conductor that penetrates the first to third insulating layers and the single crystal silicon substrate.

4. The semiconductor device according to claim 3 ,

wherein the first layer comprises the first transistor, the second transistor, a third transistor, a fourth transistor, a first wiring, and a second wiring,

wherein the first transistor is in a pixel circuit,

wherein the second transistor is in a row driver,

wherein the third transistor is in a column driver,

wherein the fourth transistor is in an analog switch, and

wherein each of the second to fourth transistors comprises a channel formation region in an oxide semiconductor layer.

5. The semiconductor device according to claim 4 , further comprising an A/D converter,

wherein the analog switch is electrically connected to the first wiring and the second wiring,

wherein the first wiring is electrically connected to the pixel circuit,

wherein the second wiring is electrically connected to the A/D converter, and

wherein the A/D converter comprises a transistor comprising silicon in a channel formation region.

6. The semiconductor device according to claim 1 ,

wherein the first conductor further penetrates the oxide semiconductor layer.

7. The semiconductor device according to claim 1 ,

wherein the oxide semiconductor layer comprises In, Zn, and M, and

wherein M is at least one of Al, Ga, Y, and Sn.

8. A module comprising:

the semiconductor device according to claim 1 ; and

a lens.

9. An electronic device comprising:

the semiconductor device according to claim 1 ; and

a display device.

10. A semiconductor device comprising:

a first transistor;

a photoelectric conversion element;

a first insulating layer; and

a second insulating layer,

wherein the first transistor comprising a channel formation region in an oxide semiconductor layer,

wherein the first transistor is provided between the first insulating layer and the second insulating layer,

wherein the first transistor comprises a first conductive layer in contact with the oxide semiconductor layer, and

wherein the first conductive layer is electrically connected to an electrode of the photoelectric conversion element via a first conductor that penetrates the first insulating layer, the first conductive layer, and the second insulating layer.

11. The semiconductor device according to claim 10 , wherein the photoelectric conversion element is provided in a single crystal silicon substrate.

12. The semiconductor device according to claim 10 , further comprising a third insulating layer, a fourth insulating layer, and a second transistor comprising silicon in a channel formation region,

wherein a top surface of a gate of the first transistor faces a top surface of a gate of the second transistor,

wherein a second conductive layer is embedded in the third insulating layer,

wherein a source, a drain, or a gate of the second transistor is electrically connected to the second conductive layer via a second conductor that penetrates the fourth insulating layer,

wherein a third conductive layer is provided on a light-receiving surface side of the photoelectric conversion element in the single crystal silicon substrate, and

wherein the second conductive layer is electrically connected to the third conductive layer via a third conductor that penetrates the first to third insulating layers and the single crystal silicon substrate.

13. The semiconductor device according to claim 12 , further comprising a third transistor, a fourth transistor, a first wiring, and a second wiring,

wherein the first transistor is in a pixel circuit,

wherein the second transistor is in a row driver,

wherein the third transistor is in a column driver,

wherein the fourth transistor is in an analog switch, and

wherein each of the second to fourth transistors comprises a channel formation region in an oxide semiconductor layer.

14. The semiconductor device according to claim 13 , further comprising an A/D converter,

wherein the analog switch is electrically connected to the first wiring and the second wiring,

wherein the first wiring is electrically connected to the pixel circuit,

wherein the second wiring is electrically connected to the A/D converter, and

wherein the A/D converter comprises a transistor comprising silicon in a channel formation region.

15. The semiconductor device according to claim 10 ,

wherein the first conductor further penetrates the oxide semiconductor layer.

16. The semiconductor device according to claim 10 ,

wherein the oxide semiconductor layer comprises In, Zn, and M, and

wherein M is at least one of Al, Ga, Y, and Sn.

17. A module comprising:

the semiconductor device according to claim 10 ; and

a lens.

18. An electronic device comprising:

the semiconductor device according to claim 10 ; and

a display device.