Abstract: An object of the present invention is to provide a photoelectric conversion device, wherein improvement of charge transfer properties when charge is output from a charge storage region and suppression of dark current generation during charge storage are compatible with each other. This object is achieved by forming a depletion voltage of a charge storage region in the range from zero to one half of a power source voltage (V), forming a gate voltage of a transfer MOS transistor during a charge transfer period in the range from one half of the power source voltage to the power source voltage (V) and forming a gate,voltage of the transfer MOS transistor during a charge storage period in the range from minus one half of the power source voltage to zero (V).

Abstract: A photoelectric conversion device comprising a semiconductor substrate of a first conduction type, and a photoelectric conversion element having an impurity region of the first conduction type and a plurality of impurity regions of a second conduction type opposite to the first conduction type. The plurality of second-conduction-type impurity regions include at least a first impurity region, a second impurity region provided between the first impurity region and a surface of the substrate, and a third impurity region provided between the second impurity region and the surface of the substrate. A concentration C1 corresponding to a peak of the impurity concentration in the first impurity region, a concentration C2 corresponding to a peak of the impurity concentration in the second impurity region and a concentration C3 corresponding to a peak of the impurity concentration in the third impurity region satisfy the following relationship: C2<C3<C1.