Patent ID: 7749913

Claim:
A semiconductor device manufacturing method comprising: forming a first silicon containing film containing silicon above a semiconductor substrate; forming an organic material film above the first silicon containing film; forming a second silicon containing film that contains silicon and that differs from the first silicon containing film above the organic material film; forming a first mask having a narrow width pattern and a wide width pattern above the second silicon containing film; patterning the second silicon containing film into a narrow width pattern and a wide width pattern by using the first mask and employing anisotropic etching; under a condition of availability of etching selectivity to the patterned second silicon containing film and the first silicon containing film, removing the first mask and patterning the organic material film into the narrow width pattern and wide width pattern by employing anisotropic etching; forming above the semiconductor substrate a third silicon containing film that contains silicon and that differs from the first silicon containing film so that the patterned second silicon containing film and the organic material film are covered; etching back the third silicon containing film to form a side wall of the third silicon containing film on a side surface of the patterned second silicon containing film and the organic material film; forming a second mask made of an organic material so that the second silicon containing film patterned to have the wide width and the side wall thereof are selectively covered; removing the second silicon containing film patterned to have the narrow width by using the second mask; and under a condition of availability of etching selectivity to the second silicon containing film patterned to have the wide width, the first silicon containing film, and the third silicon containing film, removing the organic material film patterned to have the narrow width and the second mask.