To provide a semiconductor device having improved performance.A semiconductor substrate has an element formation surface, a light receiving surface opposite thereto, a transfer transistor formed on the side of the element formation surface, a photodiode coupled in series with the transfer transistor, and a wiring formed on the element formation surface. The semiconductor substrate has, on the light receiving surface thereof, a second insulating film which is a reaction film obtained by the reaction between a first amorphous insulating film and the semiconductor substrate made of silicon. Due to holes trapped in the interface states of the second insulating film, an inversion layer is formed on the light receiving side of the semiconductor substrate. It contributes to reduction in dark current noise caused by electrons generated at the crystal defects on the light receiving surface of the semiconductor substrate or in the vicinity thereof.