An apparatus includes a first semiconductor region of a first conductivity type configured to collect a signal charge, and a connection region of a second conductivity type configured to feed a predetermined potential to a well including a second semiconductor region of the second conductivity type at a depth to which the connection region extends, a third semiconductor region of the second conductivity type at a position deeper than the connection region and the second semiconductor region, and a fourth semiconductor region between the second semiconductor region and the third semiconductor region, wherein a dopant for use in forming a semiconductor region of the first conductivity type is injected in the fourth semiconductor region, and a main carrier of the fourth semiconductor region is a carrier of the same conductivity type as a majority carrier of a semiconductor region of the second conductivity type.