| 摘要 |
An imaging device which is capable of taking images with high quality and can be manufactured at low cost is provided. An imaging device includes a first layer, a third layer and a second layer which is located between the first layer and the second layer. The first layer includes a first transistor, the second layer includes a second transistor, and the third layer includes a photodiode. A channel formation region of the first transistor includes silicon. A channel formation region of the second transistor includes an oxide semiconductor. The photodiode has a PIN structure and includes amorphous silicon. |
