Imaging device

A semiconductor device comprising:

• a first circuit and a second circuit over a first surface of a silicon substrate;
• and
• a light-controlling layer in the silicon substrate,
• wherein the first circuit comprises a first transistor and a second transistor over the first transistor,
• wherein the second circuit comprises:
• a photodiode in the silicon substrate;
• a third transistor, a fourth transistor, and a fifth transistor over the photodiode,
• wherein the light-controlling layer surrounds a side surface of the photodiode, and
• wherein:
• each of the first to fifth transistors comprises a gate, a first terminal, and a second terminal;
• the gate of the first transistor is electrically connected to the gate of the second transistor;
• the first terminal of the first transistor is electrically connected to the first terminal of the second transistor;
• the photodiode is electrically connected to the first terminal of the third transistor;
• and
• the second terminal of the third transistor is electrically connected to the first terminal of the fourth transistor and the gate of the fifth transistor.