Self-immolative polymers degrade by an end-to-end depolymerization mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus. Examples include homopolymers, mixed polymers including block copolymers, suitable for a variety of applications. A polyglyoxylate can be end-capped or capped with a linker as in a block copolymer.

Self-immolative polymers degrade by an end-to-end depolymerization mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus. Examples include homopolymers, mixed polymers including block copolymers, suitable for a variety of applications. A polyglyoxylate can be end-capped or capped with a linker as in a block copolymer.

The present disclosure relates to an atropisomer represented by the following general formula (1) and/or the general formula (2).

##STR00001##

In the formula (1) and the formula (2), R.sub.1 and R.sub.2 each independently represent any one structure of (R-1) to (R-20), and at least one of R.sub.1 and R.sub.2 represents any one of (R-1) to (R-5), provided that R.sub.1 and R.sub.2 are not same except for a case where the structure is (R-1).

The present disclosure relates to an atropisomer represented by the following general formula (1) and/or the general formula (2).

##STR00001##

In the formula (1) and the formula (2), R.sub.1 and R.sub.2 each independently represent any one structure of (R-1) to (R-20), and at least one of R.sub.1 and R.sub.2 represents any one of (R-1) to (R-5), provided that R.sub.1 and R.sub.2 are not same except for a case where the structure is (R-1).

A polymer comprising recurring units derived from a polymerizable monomer having two structures of hydroxyphenyl methacrylate having a hydroxy group substituted with an acid labile group is used as base resin in a positive resist composition, especially chemically amplified positive resist composition. The resist composition forms a resist film which is processed by lithography into a pattern of good profile having a high resolution, minimal edge roughness, and etch resistance.

A resist composition having favorable sensitivity, roughness characteristics, and etching resistance; a resist pattern formation method; and a novel compound that is useful as a resin component for the resist composition. The resist composition generates an acid upon exposure to light and changes solubility in developing solutions by the action of the acid, and includes a polymer compound having a constituent unit derived from a compound represented by general formula (a0-m0), as a resin component that changes in solubility in developing solutions by the action of an acid. In general formula (a0-m0), W.sup.01 is a polymerizable-group-containing group; W.sup.02 is an aromatic hydrocarbon group; Ra.sup.01 is a specific acid-dissociable group; Ra.sup.02 is an iodine atom or a bromine atom; and n is an integer of 1 or greater

##STR00001##

A resist composition having favorable sensitivity, roughness characteristics, and etching resistance; a resist pattern formation method; and a novel compound that is useful as a resin component for the resist composition. The resist composition generates an acid upon exposure to light and changes solubility in developing solutions by the action of the acid, and includes a polymer compound having a constituent unit derived from a compound represented by general formula (a0-m0), as a resin component that changes in solubility in developing solutions by the action of an acid. In general formula (a0-m0), W.sup.01 is a polymerizable-group-containing group; W.sup.02 is an aromatic hydrocarbon group; Ra.sup.01 is a specific acid-dissociable group; Ra.sup.02 is an iodine atom or a bromine atom; and n is an integer of 1 or greater

##STR00001##