Abstract: The present disclosure provides a method for efficiently producing an ?-alkylstyrene ?-chloroacrylate copolymer having a high monomer conversion rate. According to the present disclosure, the method for producing a copolymer containing 30 mol % to 70 mol % of an ?-alkylstyrene unit and 30 mol % to 70 mol % of an ?-chloroacrylate unit includes a step of performing solution polymerization of a monomer composition containing ?-alkylstyrene and ?-chloroacrylate, and uses ketone as a polymerization solvent for the solution polymerization.

Abstract: The present disclosure provides a method for efficiently producing an ?-alkylstyrene ?-chloroacrylate copolymer having a high monomer conversion rate. According to the present disclosure, the method for producing a copolymer containing 30 mol % to 70 mol % of an ?-alkylstyrene unit and 30 mol % to 70 mol % of an ?-chloroacrylate unit includes a step of performing solution polymerization of a monomer composition containing ?-alkylstyrene and ?-chloroacrylate, and uses ketone as a polymerization solvent for the solution polymerization.

Abstract: A substrate for forming a resist pattern comprising a resist film of the chemical amplification type and a coating film which is formed on the resist film, comprises an amorphous polyolefin or a polymer having an aromatic ring and has the same thickness as that of the resist film or smaller; and a process for forming a resist pattern of the chemical amplification type, which comprises steps of forming a pattern of a latent image in the resist film by irradiation with an ionizing radiation and converting the pattern of a latent image into a pattern of a visible image by a development treatment.

Abstract: The invention provides a resist composition which comprises a polymer (a) having structural units with an acid-labile group, and a radiation-sensitive compound (b) which forms an acid upon exposure to activated radiation, wherein the polymer (a) is a polymer obtained by polymerizing 10 to 100 wt. % of a (meth)acrylic ester (i) having, as an alcohol residue, an allyl group with at least two substituent groups and 0 to 90 wt. % of a monomer (ii) copolymerizable with the (meth)acrylic ester, and has excellent sensitivity, resolution and heat resistance, and a pattern forming process making use of the resist composition.

Abstract: The invention provides a resist composition comprising a polymer (a) having groups cleavable by an acid and a compound (b) which can form an acid upon exposure to active rays, wherein the polymer (a) is a polymer having, as the groups cleavable by an acid, groups containing a substituted allyloxy group having at least two substituents, and a resist composition comprising a resin binder (A), a compound (B) which can form an acid upon exposure to active rays, and a compound (C) having a group cleavable by an acid, wherein the compound (C) having the group cleavable by an acid is a compound having a group containing a substituted allyloxy group having at least one substituent. The resist compositions have excellent sensitivity, resolution and heat resistance and can provide excellent pattern form.

Abstract: Disclosed herein is a resist composition comprising in admixture (a) 100 parts by weight of an alkali-soluble phenolic resin, (b) 0.2-50 parts by weight of a compound which forms an acid upon exposure to active rays and consists of a specific halogen-containing aromatic compound, (c) 0.01-50 parts by weight of a compound which crosslinks the alkali-soluble phenolic resin in the presence of the acid formed from the compound (b), and (d) sufficient solvent to dissolve the foregoing composition components.

Abstract: A chemically amplified resist pattern is formed by applying chemically amplified resist, forming thereafter a layer of an amorphous polyolefines substance thereon, then exposing the chemically amplified resist, and furthermore, developing the chemically amplified resist after removing the amorphous polyolefines substance.

Abstract: A resist composition comprising in admixture (A) a compound which forms an acid upon exposure to active rays, (B) a polymer which has at least one structural unit with a group unstable to an acid and cleaves at this group in the presence of the acid derived from the compound (A) to turn alkali-soluble, and (C) a phenolic compound, and a process for forming a resist pattern using this resist composition are provided.