Patent ID: 7192883

Claim:
A method of manufacturing a semiconductor device, comprising the steps of: forming a hard mask film comprised of a nitride film on a pattern film that can easily react with an oxide film etchant chemically; patterning the hard mask film and then performing an etching process using the patterned hard mask film an etch mask to etch the pattern film; performing an etching process using a BOE solution in which HF and NH 4 F are mixed under the condition where the composition ratio of HF and NH 4 F is 1:7 to 1:10 and a temperature of the BOE solution is between 15 to 26° C. to remove a native oxide film formed on the hard mask film, wherein voids are prevented from being formed in a portion of the pattern film below the hard mask film; and performing a phosphoric acid dip-out process to remove the hard mask film.