Patent ID: 7192826

Claim:
A process for fabrication of a semiconductor device in which a capacitive element and a photodiode are mounted together on the same substrate, said process comprising the steps of: a first step of forming on a semiconductor substrate a first semiconductor layer of a first conductivity type having a lower impurity concentration than the semiconductor substrate, the semiconductor device having a capacitive element forming region and a photodiode forming region, the first semiconductor layer being formed in the capacitive element forming region and the photodiode forming region and being one of an anode and a cathode in the photodiode forming region; a second step of forming on the first semiconductor layer a second semiconductor layer of a second conductivity type, the second semiconductor layer being the other of one of an anode and a cathode, compared to the anode or cathode of the first semiconductor layer, in the photodiode forming region; a third step of performing selective oxidation on the second semiconductor layer in the capacitive element forming region, thereby forming an insulating film on the first semiconductor layer; and a fourth step of forming on the insulating film a capacitive element by sequentially laminating a lower electrode layer, a dielectric layer, and an upper electrode layer.