Patent ID: 7109126

Claim:
A method of manufacturing a semiconductor integrated circuit device in forming plural interconnections in one identical interconnection layer over a semiconductor substrate comprising steps of: (a) dividing the plural interconnections into plural groups and preparing plural sheets of photomasks each formed with a pattern for interconnections contained in each of the plural groups; and (b) forming the plural interconnections by photolithographic steps for plural times using the plural sheets of photomasks, wherein the step (b) includes the steps of: (b-1) forming a conductive film for use in interconnections over the interconnection layer; (b-2) forming an insulating film for use in mask over the conductive film for use in interconnections and forming a photoresist film over the insulating film for use in mask; (b-3) transferring the patterns for the plural interconnections to the insulating film for use in mask by photolithographic steps for plural times by using the plural sheets of photomasks; and (b-4) forming the plural interconnections by patterning the conductive film for use in interconnections by etching using the insulating film for use in mask transferred with the plural interconnection patterns as a mask.