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carbon number of 5 or more. The carbon number thereof is preferably from 6 to 30, more preferably from 7 to 25. 

Preferable cycloalkyl groups include, for example, an ada› mantyl group, a noradamantyl group, a decalinresidue group, a tricyclodecanyl group, a tetracyclododecanyl group, a nor- bomyl group, a cedrol group, a cyclopentyl group, a cyclo› hexyl group, a cycloheptyl group, a cyclooctyl group, a cyclo› decanyl group, and a cyclododecanyl group. An adamantyl group, a norbornyl group, a cyclohexyl group, a cyclopentyl group, a tetracyclododecanyl group, and a tricyclodecanyl group are more preferred. 

These alkyl group and cycloalkyl group may have a sub› stituent. This substituent includes, for example, an alkyl group (having a carbon number of 1 to 4), a halogen atom, a hydroxyl group, an alkoxy group (having a carbon number of 1 to 4), a carboxyl group, and an alkoxycarbonyl group (hav› ing a carbon number of 2 to 6). These substituents may have a further substituent. The further substituent includes, for example, a hydroxyl group, a halogen atom, and an alkoxy group. 

The structures represented by formulae (pl) to (p V) may be used for the protection of an alkali-soluble group. The alkali› soluble group includes various groups known in this technical field. 

Specific examples thereof include structures where the hydrogen atom of a carboxylic acid group, sulfonic acid group, phenol group or thiol group is substituted by a struc› ture represented by formulae (pl) to (p V). A structure where the hydrogen atom of a carboxylic acid group or sulfonic acid group is substituted by a structure represented by formulae (pl) to (p V) is preferred. 

The repeating unit having an alkali-soluble group pro› tected by a structure represented by formulae (pl) to (p V) is preferably a repeating unit represented by the following for- mula (pA): 

<img src='content_image/893925.jpg'>

In formula (pA), R represents a hydrogen atom, a halogen atom or a linear or branched alkyl group having from a carbon number of 1 to 4, and each R may be the same as or different from every other R. 

A is selected from the group consisting of a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amido group, a sulfonamide group, a urethane group, a urea group, and a combination of two or more thereof, and is preferably a single bond. 

Rp$_{1 }$ is a group represented by any one of formulae (pl) to (pV). 

The repeating unit represented by formula (pA) is most preferably a repeating unit composed of a 2-alkyl-2-adaman- tyl(meth)acrylate or a dialkyl(l-adamantyl)methyl(meth) acrylate. 

<img src='content_image/893922.jpg'>

<img src='content_image/893923.jpg'>

<img src='content_image/893924.jpg'>

In the structural formulae above, Rx represents H, CH$_{3}$, CF$_{3 }$ or CH$_{2}$0H, and each of Rxa and Rxb independently represents an alkyl group having a carbon number of 1 to 4. 

The halogen atom as Ru’ or R$_{12}$’ in formula (II-AB) includes, for example, a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. 

The alkyl group as Ru’ or R$_{12}$’ is preferably a linear or branched alkyl group having a carbon number of 1 to 10, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and a linear or branched butyl, pentyl, hexyl or heptyl group. 

The atomic group represented by Z’ is an atomic group for forming, in the resin, an alicyclic hydrocarbon repeating unit that may have a substituent. The atomic group is preferably an atomic group for forming a crosslinked alicyclic hydrocarbon repeating unit. 

Examples of the framework of the alicyclic hydrocarbon formed are the same as those of the cycloalkyl group ofR$_{12 }$to R$_{25 }$in formulae (pl) to (p VI). 

The framework of the alicyclic hydrocarbon may have a substituent, and the substituent includes, for example, R$_{13}$ ’ to R$_{16}$ ’ in formulae (II-AB!) and (II-AB2). 

In the alicyclic hydrocarbon-based acid-decomposable resin, the group capable of decomposing by an action of an acid may be contained in at least one repeating unit out of a repeating unit having an alicyclic hydrocarbon-containing partial structure represented by formulae (pl) to (p V), a repeating unit represented by formula (II-AB), and a repeat› ing unit composed of the later-described copolymerization component. 

