| abstract |
PROBLEM TO BE SOLVED: To provide a radiation-sensitive resin composition free from swelling of pattern side walls and pattern collapse in a development process, and a (meth) acrylic acid polymer that can be used for this composition. A (meth) acrylic acid polymer contains a repeating unit represented by the following formula (1) and is characterized in that the solubility in an alkali solution can be controlled by the action of an acid. [Chemical 1] (In the formula, R 1 represents a hydrogen atom or a methyl group, and each R 2 independently represents an alkyl group optionally having a linear or branched substituent having 1 to 4 carbon atoms, or 4 to 4 carbon atoms. 20 represents an alicyclic alkyl group or a monovalent hydrocarbon group in which two R 2 are bonded to each other and have an alicyclic skeleton having 4 to 9 carbon atoms, and X is a linear chain having 1 to 12 carbon atoms. Or a branched or branched linking group or an alicyclic linking group having 6 to 20 carbon atoms, and n represents an integer of 1 to 3) [Selection] None |