A positive resist composition comprising a base polymer comprising recurring units (a) having the structure of an ammonium salt of N-carbonylsulfonamide having an iodized aromatic ring, and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group exhibits a high sensitivity, high resolution, low edge roughness and dimensional uniformity, and forms a pattern of good profile after exposure and development.

A positive resist composition comprising a base polymer comprising recurring units (a) of an ammonium salt of a carboxylic acid having an iodized or brominated hydrocarbyl group and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group has a high sensitivity and resolution and forms a pattern of good profile with reduced edge roughness and improved dimensional uniformity.

A positive resist composition comprising a base polymer comprising recurring units (a) of an ammonium salt of a carboxylic acid having an iodized or brominated hydrocarbyl group and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group has a high sensitivity and resolution and forms a pattern of good profile with reduced edge roughness and improved dimensional uniformity.

A negative-tone resist composition is provided that contains a free photoacid generator and a multifunctional polymer covalently bound to a photoacid-generating moiety, where the composition is substantially free of cross-linking agents. Multifunctional polymers useful in conjunction with the resist composition are also provided, as is a process for generating a resist image on a substrate using the present compositions and polymers.

A negative-tone resist composition is provided that contains a free photoacid generator and a multifunctional polymer covalently bound to a photoacid-generating moiety, where the composition is substantially free of cross-linking agents. Multifunctional polymers useful in conjunction with the resist composition are also provided, as is a process for generating a resist image on a substrate using the present compositions and polymers.

Disclosed is a resin including a structural unit represented by formula (I) and a structural unit represented by formula (a2-A), and a resist composition: ##STR00001## wherein R.sup.1 represents a hydrogen atom or a methyl group; L.sup.1 and L.sup.2 each represent —O— or —S—; s1 represents an integer of 1 to 3; s2 represents an integer of 0 to 3; R.sup.a50 represents a hydrogen atom, a halogen atom, or an alkyl group which may have a halogen atom; R.sup.a51 represents a halogen atom, a hydroxy group, an alkyl group, an alkoxy group, an alkylcarbonyl group or the like; A.sup.a50 represents a single bond or *—X.sup.a51-(A.sup.a52-X.sup.a52).sub.nb—; A.sup.a52 represents an alkanediyl group; X.sup.a51 and X.sup.a52 each represent —O—, —CO—O— or —O—CO—; nb represents 0 or 1; and mb represents an integer of 0 to 4.

Disclosed is a resin including a structural unit represented by formula (I) and a structural unit represented by formula (a2-A), and a resist composition: ##STR00001## wherein R.sup.1 represents a hydrogen atom or a methyl group; L.sup.1 and L.sup.2 each represent —O— or —S—; s1 represents an integer of 1 to 3; s2 represents an integer of 0 to 3; R.sup.a50 represents a hydrogen atom, a halogen atom, or an alkyl group which may have a halogen atom; R.sup.a51 represents a halogen atom, a hydroxy group, an alkyl group, an alkoxy group, an alkylcarbonyl group or the like; A.sup.a50 represents a single bond or *—X.sup.a51-(A.sup.a52-X.sup.a52).sub.nb—; A.sup.a52 represents an alkanediyl group; X.sup.a51 and X.sup.a52 each represent —O—, —CO—O— or —O—CO—; nb represents 0 or 1; and mb represents an integer of 0 to 4.

A positive resist composition comprising a base polymer comprising recurring units having a nitrogen-containing tertiary ester structure exhibits a high sensitivity, high resolution, low edge roughness (LER, LWR) and small size variation, and forms a pattern of good profile after exposure and development.

A positive resist composition comprising a base polymer comprising recurring units having a nitrogen-containing tertiary ester structure exhibits a high sensitivity, high resolution, low edge roughness (LER, LWR) and small size variation, and forms a pattern of good profile after exposure and development.

An epoxy compound of formula (1) is provided. A resist composition comprising the epoxy compound is capable of adequately controlling the diffusion length of acid generated from an acid generator without sacrificing sensitivity. ##STR00001##