Abstract: A positive resist composition comprising a polymer comprising recurring units of a specific structure adapted to generate an acid upon exposure to high-energy radiation, recurring units of a lactone ring-containing structure, and acid labile units, all the recurring units being free of hydroxyl, can form a fine size pattern having a rectangular profile and improved collapse resistance.

Abstract: A resist pattern is formed by coating a first positive resist composition comprising a polymer comprising 20-100 mol % of aromatic group-containing recurring units and adapted to turn alkali soluble under the action of an acid onto a substrate to form a first resist film, coating a second positive resist composition comprising a C3-C8 alkyl alcohol solvent which does not dissolve the first resist film on the first resist film to form a second resist film, exposing, baking, and developing the first and second resist films simultaneously with a developer.

Abstract: A polymer for resist use is prepared by previously charging a reactor with a solution containing a chain transfer agent and holding at a polymerization temperature, and continuously or discontinuously adding dropwise a solution containing monomers and a polymerization initiator to the reactor for radical polymerization. The polymer has a minimized content of a substantially insoluble component. A resist composition using the polymer as a base resin produces a minimized number of defects when processed by photolithography and is useful in forming microscopic patterns.

Abstract: A polymer is provided comprising recurring units having formulas (1), (2), (3), (4), (5), and (6) in amounts of 1-60 mol % (1), 1-60 mol % (2), 1-50 mol % (3), 0-60 mol % (4), 0-30 mol % (5), and 0-30 mol % (6), and having a Mw of 3,000-30,000 and a Mw/Mn of 1.5-2.5. R1, R3, R4, R7, R9, and R11 are H or CH3, Y is methylene or O, R2 is CO2R10 when Y is methylene and R2 is H or CO2R10 when Y is O, R10 is C1-C15 alkyl which may be separated by O, R5 and R6 are H or OH, R8 is a tertiary ester type acid-labile protective group, and R12 is OH-containing fluoroalkyl. A resist composition comprising the polymer has a high resolution and is improved in line edge roughness and I/G bias.

Abstract: A polymer for resist use is prepared by previously charging a reactor with a solution containing a chain transfer agent and holding at a polymerization temperature, and continuously or discontinuously adding dropwise a solution containing monomers and a polymerization initiator to the reactor for radical polymerization. The polymer has a minimized content of a substantially insoluble component. A resist composition using the polymer as a base resin produces a minimized number of defects when processed by photolithography and is useful in forming microscopic patterns.

Abstract: A polymer is provided comprising recurring units having formulas (1), (2), (3), (4), (5), and (6) in amounts of 1-60 mol % (1), 1-60 mol % (2), 1-50 mol % (3), 0-60 mol % (4), 0-30 mol % (5), and 0-30 mol % (6), and having a Mw of 3,000-30,000 and a Mw/Mn of 1.5-2.5. R1, R3, R4, R7, R9, and R11 are H or CH3, Y is methylene or O, R2 is CO2R10 when Y is methylene and R2 is H or CO2R10 when Y is O, R10 is C1-C15 alkyl which may be separated by O, R5 and R6 are H or OH, R8 is a tertiary ester type acid-labile protective group, and R12 is OH-containing fluoroalkyl. A resist composition comprising the polymer has a high resolution and is improved in line edge roughness and I/G bias.

Abstract: Provided is a polymer useful as a base resin of a resist material featuring a high resolution, patterns with less sidewall roughness, practically acceptable etching resistance, and a substantial margin allowed for heat treatment temperature after exposure. The polymer has a weight-average molecular weight of from 1,000 to 50,000 and comprises at least one repeating unit of formula (1) below, at least one repeating unit of formula (2) below and at least one repeating unit of formula (3) below. A resist material comprising the polymer is also provided.

Abstract: A polymer comprising recurring units of formulae (1), (2), (3) and (4) increases a dissolution rate in an alkali developer under the action of an acid. R1, R2, R3 and R6 are H or CH3, R4 and R5 are H or OH, X is a tertiary exo-alkyl group having a bicyclo[2.2.1]heptane framework, represented by any of formulae (X-1) to (X-4): wherein R7 is C1–C10 alkyl, and Y is a tertiary alkyl group having an adamantane structure. A resist composition comprising the inventive polymer has a sensitivity to high-energy radiation, improved resolution and minimized proximity bias and lends itself to micropatterning with electron beams or deep UV for VLSI fabrication.

Abstract: A polymer comprising recurring units having formulae (1) and (2) and having a weight average molecular weight of 1,000 to 50,000. In the formulae, R1 and R3 are H or CH3, R4 is alkylene, R2 is a lactone structure-containing substituent group selected from formulae (R2-1) to (R2-4) wherein Y is CH2 or O, R5 is CO2R7 when Y is CH2, or R5 is H or CO2R7 when Y is O, R6 is H or alkyl, and R7 is alkyl which may be separated by at least one oxygen atom. The polymer is used as a base resin to formulate a resist composition, especially a chemically amplified positive resist composition which has a high sensitivity, resolution and dry etch resistance and forms a resist pattern having good substrate adhesion and least roughened sidewalls.

Abstract: Provided is a polymer useful as a base resin of a resist material featuring a high resolution, patterns with less sidewall roughness, practically acceptable etching resistance, and a substantial margin allowed for heat treatment temperature after exposure. The polymer has a weight-average molecular weight of from 1,000 to 50,000 and comprises at least one repeating unit of formula (1) below, at least one repeating unit of formula (2) below and at least one repeating unit of formula (3) below. A resist material comprising the polymer is also provided. In addition, provided is a pattern formation process comprising steps of applying the resist material onto a substrate, heating the film, exposing the heated film through a photomask to high energy radiation or electron beam, heating the exposed film and then developing with a developer.

Abstract: A polymer comprising recurring units of formulae (1), (2), (3) and (4) increases a dissolution rate in an alkali developer under the action of an acid. R1, R2, R3 and R6 are H or CH3, R4 and R5 are H or OH, X is a tertiary exo-alkyl group having a bicyclo[2.2.1]heptane framework, represented by any of formulae (X-1) to (X-4): wherein R7 is C1-C10 alkyl, and Y is a tertiary alkyl group having an adamantane structure. A resist composition comprising the inventive polymer has a sensitivity to high-energy radiation, improved resolution and minimized proximity bias and lends itself to micropatterning with electron beams or deep UV for VLSI fabrication.

Abstract: A polymer comprising recurring units of formulae (1), (2) and (3) increases a dissolution rate in an alkali developer under the action of an acid. R1, R2 and R5 are H or CH3, R3 and R4 are H or OH, and X is a tertiary exo-alkyl group having a bicyclo[2.2.1]heptane structure, represented by any of formulae (X-1) to (X-4): wherein R6 is a C1-C10 alkyl group. A resist composition comprising the inventive polymer has a sensitivity to high-energy radiation, improved resolution and minimized line edge roughness and lends itself to micropatterning with electron beams or deep UV for VLSI fabrication.

Abstract: A novel polymer is obtained by copolymerizing a (meth)acrylic acid derivative with a vinyl ether compound, an allyl ether compound and an oxygen-containing alicyclic olefin compound. A resist composition comprising the polymer as a base resin is sensitive to high-energy radiation, has excellent sensitivity, resolution, etching resistance, and minimized swell and lends itself to micropatterning with electron beams or deep-UV.

Abstract: A novel polymer is obtained by copolymerizing a (meth)acrylic acid derivative with a vinyl ether compound, an allyl ether compound and an oxygen-containing alicyclic olefin compound. A resist composition comprising the polymer as a base resin is sensitive to high-energy radiation, has excellent sensitivity, resolution, etching resistance, and minimized swell and lends itself to micropatterning with electron beams or deep-UV.

Abstract: A hydroxyl group-containing compound is silylated by reacting it with an organohydrosilane compound in the presence of a ruthenium complex catalyst having carbonyl groups as ligands. Silylation takes place in a short time while the amount of the catalyst is minimized.