A radiation-sensitive composition includes: a first polymer having a first structural unit that includes an acid-labile group; and a first compound including a metal cation and a first anion that is a conjugate base of an acid. The acid has a pKa of no greater than 0. The acid is preferably sulfonic acid, nitric acid, organic azinic acid, disulfonylimidic acid or a combination thereof. The first compound is preferably represented by formula (1). In the formula (1), M represents a metal cation; A represents the first anion; x is an integer of 1 to 6; R.sup.1 represents a σ ligand; and y is an integer of 0 to 5, and a sum: x+y is no greater than 6. The van der Waals volume of the acid is preferably no less than 2.5×10.sup.−28 m.sup.3.
[A.sub.xMR.sup.1.sub.y]  (1)

A radiation-sensitive composition includes: a first polymer having a first structural unit that includes an acid-labile group; and a first compound including a metal cation and a first anion that is a conjugate base of an acid. The acid has a pKa of no greater than 0. The acid is preferably sulfonic acid, nitric acid, organic azinic acid, disulfonylimidic acid or a combination thereof. The first compound is preferably represented by formula (1). In the formula (1), M represents a metal cation; A represents the first anion; x is an integer of 1 to 6; R.sup.1 represents a σ ligand; and y is an integer of 0 to 5, and a sum: x+y is no greater than 6. The van der Waals volume of the acid is preferably no less than 2.5×10.sup.−28 m.sup.3.
[A.sub.xMR.sup.1.sub.y]  (1)

A resist composition including a compound represented by formula (b1) in which R.sup.b1 represents an aryl group which may have a substituent; R.sup.b2 and R.sup.b3 each independently represents an aryl group which may have a substituent or an alkyl group which may have a substituent; provided that at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a halogen atom, and at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a sulfonyl group; and X.sup.− represents a counteranion

##STR00001##

A resist composition including a compound represented by formula (b1) in which R.sup.b1 represents an aryl group which may have a substituent; R.sup.b2 and R.sup.b3 each independently represents an aryl group which may have a substituent or an alkyl group which may have a substituent; provided that at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a halogen atom, and at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a sulfonyl group; and X.sup.− represents a counteranion

##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##

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 salt represented by formula (I), a generator and a resist composition:

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent an iodine atom, a fluorine atom or an alkyl fluoride group having 1 to 6 carbon atoms; R.sup.4, R.sup.5, R.sup.7 and R.sup.8 each independently represent a halogen atom, a hydroxy group, a haloalkyl group having 1 to 12 carbon atoms or an alkyl group having 1 to 12 carbon atoms, —CH.sub.2— included in the haloalkyl group and the alkyl group may be replaced by —O—, —CO—, —S— or —SO.sub.2−; X.sup.1 and X.sup.2 each independently represent an oxygen atom or a sulfur atom; m1 represents 1 to 5, m2 and m8 represent 0 to 5, and m4, m5 and m7 represent an integer of 0 to 4, in which 1≤m1+m7≤5, 0≤m2+m8≤5; and AI.sup.− represents an organic anion.

A salt represented by formula (I):

##STR00001##

In formula (I), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently represent a halogen atom or a perfluoroalkyl group having 1 to 6 carbon atoms, R.sup.5, R.sup.6 and R.sup.7 each independently represent a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 12 carbon atoms, and —CH.sub.2— included in the alkyl group may be replaced by —O— or —CO—, m5 represents an integer of 0 to 3, m6 represents an integer of 0 to 3, m7 represents an integer of 0 to 3, R.sup.8 and R.sup.9 each independently represent a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and —CH.sub.2— included in the alkyl group may be replaced by —O— or —CO—, and AI.sup.− represents an organic anion.

An actinic ray-sensitive or radiation-sensitive resin composition containing (A) an acid-decomposable resin, (B) a compound represented by General Formula (b1), and (C) a compound represented by General Formula (c1), in which a ratio of a content of the compound (C) to a content of the compound (B) is from 0.01% by mass to 10% by mass. In the formulae, L represents a single bond or a divalent linking group. A represents a group that decomposes by the action of an acid. B represents a group that decomposes by the action of an acid, a hydroxy group, or a carboxy group. It should be noted that at least one B represents the hydroxy group or the carboxy group. n represents an integer from 1 to 5. X represents an (n+1)-valent linking group. M.sup.+ represents a sulfonium ion or an iodonium ion.

##STR00001##

The invention comprises a process for preparing mixtures of DEFI and amide taurate (ATA) having excellent yields of ATA and substantial absence of browning of final ATA and DEFI mixtures. The process permits much greater flexibility in ratios of DEFI to ATA. The invention further relates to mixtures prepared by processes of the invention.