PURPOSE: To improve the integrating density by forming in advance and SiO2 film around the second conductor electrode and then forming the third conductor electrode.

CONSTITUTION: An n type semiconductor layer 12 is formed on a p type semiconductor substrate 11, and the first SiO2 film 13, Si3N4 film 14, the first conductor electrodes 151, 152, 153, p type semiconductor regions 161, 162, 163, the second SiO2 film 17, the second conductor electrodes 181, 182,... are sequentially formed. After the third SiO2 film 19 is formed around the electrodes 181, 182,... third conductor electrodes 201, 202... made of phosphorus-doped polycrystalline silicon are formed on the film 14 through the film 17 to be overlapped with two adjacent first electrodes 152, 153. The distance between the ends of the second and third electrodes can be shortened, thereby improving the integrating density.