Photoelectric conversion device and image pickup system

摘要

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: C 2 < C 3 < C 1.