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Among these, the structural units (I-2-1) to (I-2-8), (I-2- 13), and (I-2-14) are preferable. 

The content of the structural unit (I) in the polymer [A] is preferably 10 to 80 mo! %, more preferably 20 to 70 mo! %, and still more preferably 30 to 60 mo! %, based on the total structural units included in the polymer [A]. When the content of the structural unit (I) is within the above range, a resist pattern can be formed with more excellent sensitivity, LWR performance, and resolution. 

A monomer compound (i) that produces the structural unit (I) may be synthesized according to the following scheme, for example. 

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In the above scheme, R 1 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group, R 2 is a hydrogen atom or a monovalent hydrocarbon group, R 3 is a hydrogen atom, a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, or a monovalent aromatic hydrocarbon group, or is bonded to R $^{6 }$to form an alicyclic structure together with the carbon atoms respec› tively bonded to R 3 and R 6 , R 4 is a hydrogen atom, a monovalent chain hydrocarbon group, a monovalent alicy› clic hydrocarbon group, or a monovalent aromatic hydro- carbon group, Rs is a hydrogen atom, a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, or a monovalent aromatic hydrocarbon group, or is bonded to R $^{6 }$to form an alicyclic structure together with the carbon atoms respectively bonded to Rs and R 6 , R 6 monovalent chain hydrocarbon group, and is bonded to R 3 or Rs to form an alicyclic structure together with the carbon 

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-continued 

atoms respectively bonded to R$^{3 }$or Rs and R 6 , provided that, when R 6 and Rs are bonded to each other, R 2 is a hydrogen atom, and R 3 and R 4 are independently a hydrogen atom, a monovalent chain hydrocarbon group, a monovalent alicy- clic hydrocarbon group, or a monovalent aromatic hydro› carbon group, or R$^{3 }$and R 4 are bonded to each other to form an alicyclic structure or an aromatic heterocyclic structure together with the carbon atoms respectively bonded to R 3 and R 4 , or R 4 and Rs are bonded to each other to form an alicyclic structure or an aromatic heterocyclic structure together with the carbon atom bonded to R 4 and Rs, and some or all of the hydrogen atoms of R 2 , R 3 , and R 4 are optionally substituted with a fluorine atom, X is a halogen atom, a hydroxyl group, or R$^{2}$COO-, and R 2 is a monova- lent hydrocarbon group. 

The cyclic a,~-unsaturated ketone is reacted with the organolithium compound or the hydrogenation agent (e.g., LiAIH$_{4}$ ) in a solvent (e.g., tetrahydrofuran (THF)) to obtain the cyclic unsaturated alcohol compound. A (meth)acryloyl halide, (meth)acrylic acid, or (meth)acrylic anhydride is reacted with the unsaturated alcohol compound in the pres› ence of a base ( e.g., organic amine) to synthesize the compound (i). 

Examples of the halogen atom represented by X include a chlorine atom, a bromine atom, and an iodine atom. Among these, a chlorine atom is preferable. 

Examples of the monovalent chain hydrocarbon group represented by R 2 include those mentioned above in con- nection with the monovalent chain hydrocarbon group rep› resented by R 3 , R 4 , and Rs, and the like. 

Examples of the monovalent aromatic hydrocarbon group represented by R 2 include those mentioned above in con› nection with the monovalent aromatic hydrocarbon group represented by R 3 , R 4 , and Rs, and the like. 

The polymer [A] may include the following structural units (II) to (VII) and an additional structural unit in addition to the structural unit (I). Note that the polymer [A] may include two or more types of each structural unit. Each structural unit is described in detail below. 

Structural Unit (II) 

The structural unit (II) is a structural unit represented by the following formula (2). When the polymer [A] is used as the base polymer, the hydrophilicity of the resulting resist film can be appropriately adjusted by incorporating the structural unit (II) in the polymer [A]. When the polymer [A] is used as the water-repellent additive, an improvement in hydrophobicity can be achieved by incorporating the struc› tural unit (II) that includes a fluorine atom in the polymer [A], and the dynamic contact angle of the surface of a resist film formed using the resulting radiation-sensitive resm composition can be further improved. 

wherein R 7 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group, G is a single bond, an oxygen atom, a sulfur atom, ----C0-0-, -S0$_{2}$-0- NH-, --CO-NH-, or ---0-CO-NH-, and W is a monovalent chain hydrocarbon group having 1 to 6 carbon atoms that includes at least one fluorine atom, or a mon- 

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