A flow battery includes a first liquid containing a redox mediator, a first electrode, a first active material, and a first circulator that circulates the first liquid between the first electrode and the first active material. The redox mediator contains a heteranthrene compound. The redox mediator contains a heteranthrene compound. The heteranthrene compound has a skeletal structure including a central ring structure, the central ring structure containing no nitrogen.

Provided are a carboxylate capable of producing a resist pattern with satisfactory CD uniformity (CDU), and a resist composition. Disclosed are a carboxylate represented by formula (I) and a resist composition:

##STR00001##

wherein Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, X.sup.1 represents an oxygen atom or a sulfur atom, R.sup.1 represents a halogen atom or a haloalkyl group having 1 to 12 carbon atoms, R.sup.2 represents 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— or —CO—, m1 represents an integer of 1 to 6, m2 represents an integer of 0 to 4, and Z.sup.+ represents an organic cation.

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

##STR00001##

wherein Q.sup.1 and Q.sup.2 each represent a fluorine atom or a perfluoroalkyl group; R.sup.11 and R.sup.12 each represent a hydrogen atom, a fluorine atom or a perfluoroalkyl group; z represents an integer of 0 to 6; X.sup.1 and X.sup.2 each represent *—CO—O—, *—O—CO—, etc.; L.sup.1 represents a single bond or a hydrocarbon group which may have a substituent; A.sup.1 represents a group having a lactone structure which may have a substituent; L.sup.2 and L.sup.3 each represent a single bond or an alkanediyl group; R.sup.1 represents an iodine atom or a haloalkyl group; R.sup.2 represents a halogen atom, a hydroxy group, a haloalkyl group or an alkyl group; m2 represents an integer of 0 to 4; and Z.sup.+ represents an organic cation.

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 containing a compound represented by the general formula (bd1-1), (bd1-2) or (bd1-3); in the formula, Rx.sup.1 to Rx.sup.4 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure; Ry.sup.1 to Ry.sup.2 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure, Rz.sup.1 to Rz.sup.4 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure. At least one of Rx.sup.1 to Rx.sup.4, Ry.sup.1 to Ry.sup.2 and Rz.sup.1 to Rz.sup.4 has an anion group, M.sub.1.sup.m+ represents a sulfonium cation having a sulfonyl group, R.sup.001 to R.sup.003 each independently represent a monovalent organic group; provided that at least one of R.sup.001 to R.sup.003 is an organic group having an acid dissociable group; and M.sub.3.sup.m+ represents an m-valent organic cation having an electron-withdrawing group. ##STR00001##

A resist composition containing a compound represented by the general formula (bd1-1), (bd1-2) or (bd1-3); in the formula, Rx.sup.1 to Rx.sup.4 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure; Ry.sup.1 to Ry.sup.2 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure, Rz.sup.1 to Rz.sup.4 represent a hydrocarbon group or a hydrogen atom or may be mutually bonded to form a ring structure. At least one of Rx.sup.1 to Rx.sup.4, Ry.sup.1 to Ry.sup.2 and Rz.sup.1 to Rz.sup.4 has an anion group, M.sub.1.sup.m+ represents a sulfonium cation having a sulfonyl group, R.sup.001 to R.sup.003 each independently represent a monovalent organic group; provided that at least one of R.sup.001 to R.sup.003 is an organic group having an acid dissociable group; and M.sub.3.sup.m+ represents an m-valent organic cation having an electron-withdrawing group. ##STR00001##

A resist composition comprising a sulfonium compound of specific structure as PAG has excellent lithography performance factors such as minimal defects, high sensitivity, improved LWR and CDU, and is a quite effective resist material for precise micropatterning.

A resist composition comprising a sulfonium compound of specific structure as PAG has excellent lithography performance factors such as minimal defects, high sensitivity, improved LWR and CDU, and is a quite effective resist material for precise micropatterning.

A salt represented by the formula (I): ##STR00001##

A salt represented by the formula (I): ##STR00001##