A first circuit layer including a first semiconductor substrate with photoelectric conversion unit that photoelectrically converts incident light and generates charge, and a first wiring layer with wiring that reads out signal based upon charge generated by the photoelectric conversion unit; second circuit layer including a second wiring layer with wiring connected to the wiring of the first wiring layer, and a second semiconductor substrate with a through electrode connected to the wiring of the second wiring layer; third circuit layer including a third semiconductor substrate with a through electrode connected to the through electrode of the second circuit layer, and third wiring layer with wiring connected to the through electrode of the third semiconductor substrate; and a fourth circuit layer including a fourth wiring layer with wiring connected to the wiring of the third wiring layer, and fourth semiconductor substrate connected to the wiring of the fourth wiring layer.