PATTERN FORMING METHOD AND BILAYER FILM FOR PATTERN FORMATION

摘要

PROBLEM TO BE SOLVED: To provide a pattern forming method capable of forming a dense pattern independently of standing waves and capable of further forming a resist pattern having a high aspect ratio by using an underlayer film excellent in dry etching resistance and usable as a thin film in combination with a specified polysiloxane-base radiation-sensitive resin composition having high transparency at <=193 nm wavelength, and to provide a bilayer film for pattern formation. SOLUTION: In the pattern forming method, a coating film comprising a radiation-sensitive resin composition comprising an acid-dissociable group- containing polysiloxane which is made alkali-soluble when the acid-dissociable group is dissociated is formed on an underlayer film comprising a polymer having >=80 wt.% carbon content and a weight average molecular weight (expressed in terms of polystyrene) of 500-100,000 and irradiation with radiation is carried out. The bilayer film for pattern formation is obtained by forming a coating film comprising the radiation-sensitive resin composition on the underlayer film.