Patent ID: 8847346

Claim:
A solid-state image pickup device including a pixel, the pixel comprising: a photoelectric conversion portion configured to generate charges in accordance with incident light; a charge holding portion including a first-conductivity-type first semiconductor region configured to hold the charges generated by the photoelectric conversion portion in a portion different from the photoelectric conversion portion; and a transfer portion including a transfer gate electrode provided on a region between the first semiconductor region and a sense node, wherein a second-conductivity-type second semiconductor region is disposed under the first semiconductor region so as to form a PN junction together with the first semiconductor region, and wherein, at a depth where a peak of a second-conductivity-type impurity concentration of the second semiconductor region exists, the second-conductivity-type impurity concentration of the second semiconductor region is higher than a second-conductivity-type impurity concentration of a region, under the transfer gate electrode, at a same depth as the peak.