Patent ID: 8049293

Claim:
A solid-state image pickup device comprising: a first semiconductor region ( 1052 b ) of a first conductivity type between an electric charge accumulation region ( 1052 a ) of the first conductivity type and a second semiconductor region ( 1052 c ) of the first conductivity type; a third semiconductor region ( 1052 c 1 ) of the first conductivity type between a semiconductor well region ( 1046 ) of a second conductivity type and said second semiconductor region ( 1052 c ), wherein an impurity concentration of the first conductivity type for said electric charge accumulation region ( 1052 a ) is higher than an impurity concentration of the first conductivity type for said third semiconductor region ( 1052 c 1 ), wherein an impurity concentration of the first conductivity type for said first semiconductor region ( 1052 b ) is higher than an impurity concentration of the first conductivity type for said electric charge accumulation region ( 1052 a ).