US Patent 7218349 Semiconductor device

A semiconductor device is provided in which each pixel includes an electric circuit (a bootstrap circuit) for generating an electric potential that is higher than a voltage given through capacitative coupling. Also, there is provided a semiconductor device in which a sufficient signal amplitude can be attained by using the electric circuit to set a potential difference between both terminals of a photoelectric conversion element to the same value as the power source potential. Further, there is provided a semiconductor device in which the number of manufacturing steps is reduced by using transistors having a single polarity to constitute each pixel, thereby achieving increased yield and reduced costs.