Patent attributes
An object of the present invention is to simultaneously realize the enlargement of a dynamic range and the downsizing of a pixel. An additional capacitor CS is composed by using: a first capacitor formed of a first diffusion layer, a second diffusion layer and a P well by layering the P well, the first diffusion layer, a first dielectric film, a first polysilicon layer, a second dielectric film and a second polysilicon layer; a second capacitor formed of the second diffusion layer, the first polysilicon layer and the first dielectric film; and a third capacitor formed of the first polysilicon layers, a second polysilicon layer, and a second dielectric film. Thereby, the additional capacitor CS for accumulating carriers overflown from a photodiode PD can secure a required capacitance value while making its size as small as possible.
