A method comprises preparing a semiconductor substrate having a first portion, and a second portion including a first region and a second region; forming an active region in the first portion, and an isolating portion of an insulator defining the active region in the second portion; forming a first semiconductor region of a first conductivity type configuring a first photoelectric conversion element, a second semiconductor region of first conductivity type configuring a second photoelectric conversion element, a third semiconductor region of first conductivity type, a fourth semiconductor region of the conductivity type, a first gate electrode configuring a first transfer transistor, and a second gate electrode configuring a second transfer; exposing the first region of the semiconductor substrate, and performing ion implantation masked by a first photoresist pattern covering the second region of the semiconductor substrate, thus forming a fifth semiconductor region of a second conductivity type.