Abstract: A sulfonium salt having a triphenylsulfonium cation and a sulfite anion within the molecule is best suited as a photoacid generator in chemically amplified resist compositions. Upon exposure to high-energy radiation, the sulfonium salt generates a sulfonic acid, which facilitates efficient scission of acid labile groups in chemically amplified positive resist compositions. Because of substantial non-volatility under high vacuum conditions in the EB or EUV lithography, the risk of the exposure tool being contaminated is minimized.

Abstract: The photoacid generator produces a sulfonic acid which has a bulky cyclic structure in the sulfonate moiety and a straight-chain hydrocarbon group and thus shows a controlled acid diffusion behavior and an adequate mobility. The PAG is fully compatible with a resin to form a resist composition which performs well during the device fabrication process and solves the problems of resolution, LWR, and exposure latitude.

Abstract: A polymer comprising a high proportion of aromatic ring structure-containing units and containing an aromatic sulfonic acid sulfonium salt on a side chain is used to form a chemically amplified positive photoresist composition which is effective in forming a resist pattern having high etch resistance. The polymer overcomes the problems of dissolution in solvents for polymerization and purification and in resist solvents.

Abstract: A pattern is formed by coating a first positive resist composition comprising a base resin, a photoacid generator, and a base generator onto a substrate to form a first resist film, patternwise exposure, PEB, and development to form a first resist pattern, heating the first resist pattern for causing the base generator to generate a base for inactivating the pattern to acid, coating a second positive resist composition comprising a C3-C8 alcohol and an optional C6-C12 ether onto the first resist pattern-bearing substrate to form a second resist film, patternwise exposure, PEB, and development to form a second resist pattern.

Abstract: There is disclosed a sulfonate shown by the following general formula (2). R1—COOC(CF3)2—CH2SO3?M+??(2) (In the formula, R1 represents a linear, a branched, or a cyclic monovalent hydrocarbon group having 1 to 50 carbon atoms optionally containing a hetero atom. M+ represents a cation.) There can be provided: a novel sulfonate which is effective for a chemically amplified resist composition having a sufficiently high solubility (compatibility) in a resist solvent and a resin, a good storage stability, a PED stability, a further wider depth of focus, a good sensitivity, in particular a high resolution and a good pattern profile form; a photosensitive acid generator; a resist composition using this; a photomask blank, and a patterning process.

Abstract: A sulfonium salt has formula (1) wherein R1 is a monovalent hydrocarbon group except vinyl and isopropenyl, R2, R3, and R4 are alkyl, alkenyl, oxoalkyl, aryl, aralkyl or aryloxoalkyl or may bond together to form a ring with the sulfur atom, and n is 1 to 3. A chemically amplified resist composition comprising the sulfonium salt is capable of forming a fine feature pattern of good profile after development due to high resolution, improved focal latitude, and minimized line width variation and profile degradation upon prolonged PED.

Abstract: There is disclosed a resist lower-layer composition configured to be used by a multi-layer resist method used in lithography to form a layer lower than a photoresist layer acting as a resist upper layer film, wherein the resist lower-layer composition becomes insoluble or poorly-soluble in an alkaline developer after formation of the lower layer, and wherein the resist lower-layer composition comprises, at least, a thermal acid generator for generating an acid represented by the general formula (1) by heating at a temperature of 100° C. or higher.

Abstract: A material comprising a novolac resin having a C6-C30 aromatic hydrocarbon group substituted with a sulfo group or an amine salt thereof is useful in forming a photoresist undercoat. The undercoat-forming material has an extinction coefficient sufficient to provide an antireflective effect at a thickness of at least 200 nm, and a high etching resistance as demonstrated by slow etching rates with CF4/CHF3 gas for substrate processing.

Abstract: A polymerizable anion-containing sulfonium salt having formula (1) is provided wherein R1 is H, F, methyl or trifluoromethyl, R2, R3 and R4 are C1-C10 alkyl, alkenyl or oxoalkyl or C6-C18 aryl, aralkyl or aryloxoalkyl, or two of R2, R3 and R4 may bond together to form a ring with S, A is a C2-C20 hydrocarbon group having cyclic structure, and n is 0 or 1. The sulfonium salt generates a very strong sulfonic acid upon exposure to high-energy radiation. A resist composition comprising a polymer derived from the sulfonium salt is also provided.

Abstract: A polymerizable anion-containing sulfonium salt having formula (1) is provided wherein R1 is H, F, methyl or trifluoromethyl, R2, R3 and R4 are C1-C10 alkyl, alkenyl or oxoalkyl or C6-C18 aryl, aralkyl or aryloxoalkyl, or two of R2, R3 and R4 may bond together to form a ring with S, A is a C1-C10 organic group, and n is 0 or 1. The sulfonium salt generates a very strong sulfonic acid upon exposure to high-energy radiation. A resist composition comprising a polymer derived from the sulfonium salt is also provided.

Abstract: Photoacid generators generate sulfonic acids of formula (1a) or (1c) upon exposure to high-energy radiation. R1—COOCH(CF3)CF2SO3?H+??(1a) R1—O—COOCH(CF3)CF2SO3?H+??(1c) R1 is a C20-C50 hydrocarbon group having a steroid structure. The photoacid generators are compatible with resins and can control acid diffusion and are thus suited for use in chemically amplified resist compositions.

Abstract: There is disclosed a chemically-amplified positive resist composition comprising, as main components, (A) a base polymer, which contains one or more kinds of a monomer unit represented by the following general formula (1) and the like, and is an alkali-insoluble polymer whose hydroxyl group is partly protected by an acetal group while alkali-soluble when deprotected by an acid catalyst, (B) a sulfonium salt containing a sulfonate anion, (C) a basic component, and (D) an organic solvent. In a lithography technology by a photo resist, an extremely high temporal stability is necessary. In addition, it must give a good pattern profile not dependent on a substrate and have a high resolution power. There can be provided a chemically-amplified positive resist composition which can solve these problems simultaneously, a resist patterning process using the same, and a method for producing a photo mask blank.

Abstract: There is disclosed a resist composition which shows high sensitivity and high resolution on exposure to high energy beam, provides reduced Line Edge Roughness because swelling at the time of development is reduced, provides minor amounts of residue after development, has excellent dry etching resistance, and can also be used suitably for the liquid immersion lithography; and a patterning process using the resist composition. There can be provided a resist composition which comprises, at least, a polymer including repeating units represented by the following general formulae (a) and (b).

Abstract: A resist composition comprising as a quencher a nitrogen-containing organic compound bearing a nitrogen-containing heterocycle and having a molecular weight of at least 380 exhibits a high resolution and satisfactory mask coverage dependence and is useful in microfabrication using electron beam or deep-UV.

Abstract: Photoacid generators generate sulfonic acids of formula (1a) or (1b) upon exposure to high-energy radiation. R1—COOCH2CF2SO3?H+??(1a) R1—O—COOCH2CF2SO3?H+??(1b) R1 is a monovalent C20-C50 hydrocarbon group of steroid structure which may contain a heteroatom. The bulky steroid structure ensures adequate control of acid diffusion. The photoacid generators are compatible with resins and suited for use in chemically amplified resist compositions.

Abstract: A polymer comprising recurring units having formulae (1), (2) and (3) is provided as well as a chemically amplified resist composition comprising the same. R1 is H, F, CH3 or CF3, Rf is H, F, CF3 or C2F5, A is an optionally fluorine or oxygen-substituted divalent organic group, R2, R3 and R4 are alkyl, alkenyl, oxoalkyl, aryl, aralkyl or aryloxoalkyl, or may form a ring with the sulfur atom, N=0-2, R8 is H or alkyl, B is a single bond or optionally oxygen-substituted divalent organic group, a=0-3, b=1-3, and X is an acid labile group. The polymer generates a strong sulfonic acid which provides for effective cleavage of acid labile groups in a chemically amplified resist composition.

Abstract: Photoacid generators generate sulfonic acids of formula (1a) upon exposure to high-energy radiation. ROC(?O)R1—COOCH2CF2SO3?H+??(1a) RO is OH or C1-C20 organoxy, R1 is a divalent C1-C20 aliphatic group or forms a cyclic structure with RO. The photoacid generators are compatible with resins and can control acid diffusion and are thus suited for use in chemically amplified resist compositions.

Abstract: A polymer comprising recurring units of a sulfonium salt represented by formula (1) is provided as well as a chemically amplified resist composition comprising the same. R1 is H, F, methyl or trifluoromethyl, R2 to R4 are C1-C10 alkyl or alkoxy, R5 is C1-C30 alkyl or C6-C14 aryl, k, m and n are 0 to 3. The recurring units generate a sulfonic acid upon exposure to high-energy radiation so as to facilitate effective scission of acid labile groups in the resist composition. The resist composition exhibits excellent resolution and a pattern finish with minimal LER.

Abstract: A positive resist composition comprises a polymer comprising recurring units having a sulfonium salt incorporated therein as a base resin which becomes soluble in alkaline developer under the action of acid. The polymer generates a strong sulfonic acid upon exposure to high-energy radiation so as to facilitate effective scission of acid labile groups in the resist composition.

Abstract: A sulfonium salt having a polymerizable anion generates a strong sulfonic acid upon exposure to high-energy radiation so that it facilitates effective scission of acid labile groups in chemically amplified resist compositions. It is useful as a monomer from which a base resin for use in radiation-sensitive resist compositions is derived.