Disclosed are a photoacid generator, a photoresist composition including the same, and a method of preparing the photoacid generator. The photoacid generator may include a compound represented by Formula 1: ##STR00001##
wherein, in Formula 1, CY, A1, A2, and B are respectively described in the specification.

Disclosed are a photoacid generator, a photoresist composition including the same, and a method of preparing the photoacid generator. The photoacid generator may include a compound represented by Formula 1: ##STR00001##
wherein, in Formula 1, CY, A1, A2, and B are respectively described in the specification.

Disclosed are a salt represented by formula (I), an acid generator, and a resist composition comprising the same:

##STR00001##

wherein R.sup.1 and R.sup.2 each represent a hydroxy group, *—O—R.sup.10, *—O-L.sup.10-CO—O—R.sup.10; L.sup.10 represents an alkanediyl group; R.sup.10 represents an acid-labile group; R.sup.4, R.sup.5, R.sup.7 and R.sup.8 each represent a halogen atom, a haloalkyl group or a hydrocarbon group; A.sup.1 and A.sup.2 each represent a hydrocarbon group, the hydrocarbon group may have a substituent, and —CH.sub.2— included in the hydrocarbon group may be replaced by —O—, —CO—, —S— or —SO.sub.2—; m1 represents an integer of 1 to 5, m2 and m8 represent an integer of 0 to 5, m4, m5 and m7 represent an integer of 0 to 4, 1≤m1+m7≤5, 0≤m2+m8≤5; and AI.sup.− represents an organic anion.

Provided are a salt capable of producing a resist pattern with satisfactory CD Uniformity (CDU), an acid generator, and a resist composition. Disclosed are a salt represented by formula (I), an acid generator, and a resist composition:

##STR00001##

wherein, in formula (I), R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 and R.sup.9 each represent a halogen atom, a haloalkyl group, etc.; A.sup.1, A.sup.2 and A.sup.3 each represent a hydrocarbon group, etc.; m1 and m4, m5, m6 and m7 represent an integer of 0 to 5, m2, m3, m8 and m9 represent an integer of 0 to 4, 0≤m1+m7≤5, 0≤m2+m8≤4, 0≤m3+m9≤4, and at least one of m1, m2 and m3 represents an integer of 1 or more; X.sup.4 represents a single bond, —CH.sub.2—, —O—, —S—, —CO—, —SO— or —SO.sub.2—; and AI.sup.− represents an organic anion.

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

A monomer has the structure ##STR00001##
wherein R is an organic group comprising a polymerizable carbon-carbon double bond or carbon-carbon triple bond; X and Y are independently at each occurrence hydrogen or a non-hydrogen substituent; EWG1 and EWG2 are independently at each occurrence an electron-withdrawing group; p is 0, 1, 2, 3, or 4; n is 1, 2, 3, or 4; and M.sup.+ is an organic cation. A polymer prepared from monomer is useful as a component of a photoresist composition.

A monomer has the structure ##STR00001##
wherein R is an organic group comprising a polymerizable carbon-carbon double bond or carbon-carbon triple bond; X and Y are independently at each occurrence hydrogen or a non-hydrogen substituent; EWG1 and EWG2 are independently at each occurrence an electron-withdrawing group; p is 0, 1, 2, 3, or 4; n is 1, 2, 3, or 4; and M.sup.+ is an organic cation. A polymer prepared from monomer is useful as a component of a photoresist composition.

A radiation-sensitive resin composition includes a polymer including a phenolic hydroxyl group, a compound represented by formula (1-1) or formula (1-2), and a compound represented by formula (2). In the formula (1-1), a sum of a, b, and c is no less than 1; at least one of R.sup.1, R.sup.2, and R.sup.3 represents a fluorine atom or the like; and R.sup.4 and R.sup.5 each independently represent a hydrogen atom, a fluorine atom, or the like. In the formula (1-2), in a case in which d is 1, R.sup.6 represents a fluorine atom or the like, and in a case in which d is no less than 2, at least one of the plurality of R.sup.6s represents a fluorine atom or the like; and R.sup.8 represents a single bond or a divalent organic group having 1 to 20 carbon atoms. ##STR00001##

A radiation-sensitive resin composition includes a polymer including a phenolic hydroxyl group, a compound represented by formula (1-1) or formula (1-2), and a compound represented by formula (2). In the formula (1-1), a sum of a, b, and c is no less than 1; at least one of R.sup.1, R.sup.2, and R.sup.3 represents a fluorine atom or the like; and R.sup.4 and R.sup.5 each independently represent a hydrogen atom, a fluorine atom, or the like. In the formula (1-2), in a case in which d is 1, R.sup.6 represents a fluorine atom or the like, and in a case in which d is no less than 2, at least one of the plurality of R.sup.6s represents a fluorine atom or the like; and R.sup.8 represents a single bond or a divalent organic group having 1 to 20 carbon atoms. ##STR00001##