Resist composition, method for forming resist pattern, and polymer compound

A resist composition which generates an acid upon exposure and whose solubility in a developing solution changes under the action of an acid, the composition comprising:

• a base material (A) whose solubility in the developing solution changes under the action of an acid and an acid generator component (B),
• wherein the base material (A) comprises a polymer compound (A1) having a structural unit (a01), a structural unit (a02), and a structural unit (a03), wherein
• a ratio of the structural unit (a03) in the polymer compound (A1) is greater than 0 mol % and equal to or less than 10 mol % with respect to the total of all the structural units constituting the polymer compound (A1),
• the structural unit (a01) is represented by general formula (a0-1) shown below:
• wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Va01 is a divalent hydrocarbon group which may have an ether bond, nao1 is an integer of 0 to 2, and Ra0″ is an acid dissociable group represented by general formula (a0-r1-1), (a0-r1-2), or (a0-r1-3) shown below:
• wherein in general formula (a0-r1-1), Ya0 represents a carbon atom, Xa0 is a group which forms an alicyclic hydrocarbon group together with Ya0, Ra0 is an aromatic hydrocarbon group which may have a substituent, or a group represented by general formula (a0-f1) shown below:
• wherein Ra01 to Ra03 are each independently an aliphatic hydrocarbon group which may have a substituent, or a hydrogen atom, and two or more of Ra01 to Ra03 may be bonded to each other to form a cyclic structure;
• in general formula (a0-r1-2), Ya00 represents a carbon atom, Xa00 is a group which forms a condensed ring of an alicyclic hydrocarbon group and an aromatic hydrocarbon group together with Ya00, and Ra00 is an alkyl group having 1 to 10 carbon atoms, an aromatic hydrocarbon group which may have a substituent, or a group represented by general formula (a0-f1) shown above;
• in general formula (a0-r1-3), Ra04 and Ra05 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom, at least one hydrogen atom of the chain saturated hydrocarbon group may be substituted, and Ra06 is an aromatic hydrocarbon group which may have a substituent;
• and
• a symbol of * represents a bond;
• the structural unit (a02) is represented by general formula (a0-2) shown below:
• wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Va02 is a divalent linking group containing a heteroatom, or a single bond, Raw is a monovalent organic group, na021 is an integer of 0 to 3, and nao22 is an integer of 1 to 3;
• and
• the structural unit (a03) is represented by general formula (a0-3) shown below:
• wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Va03 is a divalent hydrocarbon group which may have an ether bond, and na03 is an integer of 0 to 2.