Patent ID: 6912019

Claim:
A method of manufacturing a semiconductor device, comprising the steps of: forming a semiconductor film on a substrate; forming an insulating film on the semiconductor film; forming a conductive film on the insulating film; covering a partial upper surface of the conductive film with a resist pattern, the semiconductor film protruding from edges of the resist pattern; etching the conductive film by using the resist pattern as a mask to leave a patterned conductive film, said etching step being executed under conditions that sidewall additives made of reaction byproducts of material of the conductive film and material of the resist pattern reacted with etching gas during etching are generated on side walls of the patterned conductive film; etching the insulating film by using as a mask the patterned conductive film and side wall additives attached to the side walls of the patterned conductive film; removing the side wall additives; implanting impurities in the semiconductor film using the patterned conductive film as a mask under conditions that the impurities transmit through the insulating film, which expose on both sides of the patterned conductive film after removing the side wall additives; and removing the resist pattern after etching the conductive film.