Patent ID: 7382009

Claim:
A solid state image pickup device, comprising an arrangement of a plurality of pixels each of which includes at least: a photodiode for accumulating a signal charge generated by an incident light; and an amplifying MOS transistor receiving the signal charge at a gate electrode, amplifying the signal charge and outputting an amplified signal, wherein: the amplifying MOS transistor has a source and drain of a first conductivity type formed in a first semiconductor region which is the same conductivity type as a source and drain of the amplifying MOS transistor, the first semiconductor region has an impurity concentration lower than that of the source and drain, a second semiconductor region of a second conductivity type opposite to the first conductivity type is formed at least under a gate of the amplifying MOS transistor, wherein the first semiconductor region, between a channel region of the amplifying MOS transistor and the second semiconductor region, is depleted during at least a period of driving the amplifying MOS transistor for an amplifying operation.