To provide a method for manufacturing a semiconductor device capable of reducing manufacturing costs by omitting a photolithography step.
A method for manufacturing a semiconductor device comprises the steps of: forming a first insulating film on a memory cell region M of a semiconductor substrate 1; forming first conductive films 6c and 6d1 on a first well of a peripheral circuit region C of the semiconductor substrate 1 and forming a second insulating film 6e on the first conductive film 6c; forming second conductive films 6c and 6d2 on the first insulating film, the second insulating film 6e, and a second well of the peripheral circuit region; forming a third insulating film 6h so as to cover the second conductive films 6c and 6d2; exposing the second conductive film 6d2 on the first and second insulating films so as to leave the third insulating film 6h provided on the second conductive film on the second well by etching back the third insulating film 6h; and etching the second conductive films 6c and 6d2 on the first and second insulating films using the third insulating film 6h on the second conductive film as a mask.
Ishibashi Masayuki
Masaaki Ogata