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 radiation-sensitive resin composition contains: a polymer having an acid-labile group, a radiation-sensitive acid generator, a compound represented by the following formula (1), and a solvent. In the formula (1), X represents an oxygen atom or a sulfur atom; R.sup.1 represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R.sup.2 to R.sup.5 each independently represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and optionally two or more of R.sup.2 to R.sup.5 taken together represent an alicyclic structure having 3 to 20 ring atoms or an aliphatic heterocyclic structure having 3 to 20 ring atoms together with the carbon atom to which the two or more of R.sup.2 to R.sup.5 bond; Z.sup.n+ represents a cation having a valency of n; and n is an integer of 1 to 3. ##STR00001##

A radiation-sensitive resin composition contains: a polymer having an acid-labile group, a radiation-sensitive acid generator, a compound represented by the following formula (1), and a solvent. In the formula (1), X represents an oxygen atom or a sulfur atom; R.sup.1 represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R.sup.2 to R.sup.5 each independently represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and optionally two or more of R.sup.2 to R.sup.5 taken together represent an alicyclic structure having 3 to 20 ring atoms or an aliphatic heterocyclic structure having 3 to 20 ring atoms together with the carbon atom to which the two or more of R.sup.2 to R.sup.5 bond; Z.sup.n+ represents a cation having a valency of n; and n is an integer of 1 to 3. ##STR00001##

An onium salt having formula (1) serving as an acid diffusion inhibitor and a chemically amplified resist composition comprising the acid diffusion inhibitor are provided. When processed by lithography, the resist composition forms a pattern having minimal defects and excellent lithography performance factors such as CDU, LWR and DOF.

##STR00001##

A resist composition comprising a quencher containing a sulfonium salt having the formula (A). ##STR00001##

A resist composition comprising a quencher containing a sulfonium salt having the formula (A). ##STR00001##

A novel carboxylic acid iodonium salt and a resist composition comprising the same as a quencher are provided. When resist composition is processed by photolithography using KrF or ArF excimer laser, EB or EUV, there is formed a resist pattern which is improved in rectangularity, MEF, LWR, and CDU.

A novel carboxylic acid iodonium salt and a resist composition comprising the same as a quencher are provided. When resist composition is processed by photolithography using KrF or ArF excimer laser, EB or EUV, there is formed a resist pattern which is improved in rectangularity, MEF, LWR, and CDU.

An aim of the present disclosure is to provide a method for producing a fluoroalkoxide, said method being more useful than conventional methods, and the like. The aim can be achieved by a method for producing a compound represented by the following formula (1):

##STR00001## (wherein R.sup.1 is a fluoroalkyl group optionally containing an oxygen atom between carbon atoms, or a fluoroalkoxy group optionally containing an oxygen atom between carbon atoms, and each R.sup.2 is identical to or different from each other and is a hydrocarbon group), the method comprising the step of reacting a compound represented by the following formula (2):

##STR00002## with a compound represented by the following formula (3):

.sup.⊖F.sup.⊕NR.sup.2).sub.4  (3).