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a hydrogen atom, or an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms, specifically a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group, or an octyl group). 

[0281] M$^{41 }$is preferably a single bond, an alkylene group, or a divalent linking group comprising a combination of an alkylene group and at least one of ---0-, --CO-, -CS-, and-N (Ro)-, and more preferably a single bond, an alky lene group, or a divalent linking group comprising a combination of an alkylene group and ---0-. Ro has the same meaning with the above Ro. 

[0282] The alkyl group as Q is the same with the alkyl group as R$^{41 }$described above. 

[0283] As the alicyclic group and aromatic cyclic group as Q, the cycloalkyl group andaryl group as R$^{41 }$described above are exemplified. The carbon atom number is preferably 3 to 18. Incidentally, in the invention, a group obtained by linking a plurality of aromatic rings via a single bond ( e.g., a biphenyl group and a terphenyl group) is also included in the aromatic group as Q. 

[0284] As the alicyclic group containing a hetero atom and the aromatic cyclic group containing a heteroatom, for example, thiirane, cyclothiolane, thiophene, furan, pyrrole, benzothiophene, benzofuran, benzopyrrole, triazine, imida› zole, benzimidazole, triazole thiadiazole, thiazole, and pyr› rolidone are exemplified. Incidentally, in the invention, a group obtained by linking "a plurality of aromatic rings con› taining hetero-atoms" via a single bond ( e.g., a viologen group) is also included in the aromatic group as Q. 

[0285] The alicyclic group and aromatic cyclic group as Q may have a substituent, for example, an alkyl group, a cycloalkyl group, a cyano group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycar› bonyl group are exemplified. 

[0286] (-M $^{41}$-Q) is especially preferably a methyl group, an ethyl group, a cyclohexyl group, a norbomyl group, an ary› loxyethyl group, a cyclohexylethyl group, or an arylethyl group. 

[ 0287] As the case of forming a ring by bonding at least two of R 41 , M 41 and Q to each other, for example, a case of bonding either M$^{41 }$or Q to R$^{41 }$to form a propylene group or a butylene group and to form a 5- or 6-membered ring con› taining an oxygen atom is exemplified. 

[0288] Taking the sum total of the carbon atom number of R 41 , M 41 and Q as Ne, in the case where Ne is large, the change of the solubility of the resin (P) in an alkali becomes large before and after leaving of the group represented by formula ( c ), and so the dissolution contrast is preferably improved. The range of Ne is preferably 4 to 30, more pref› erably 7 to 25, and especially preferably 7 to 20. When Ne is 30 or less, the reduction of the glass transition temperature of the resin (P) is suppressed, the exposure latitude (EL) of the resist is prevented from lowering, and the residue after leav› ing of the group represented by formula (c) is inhibited from remaining on the resist pattern as a defect, and so preferred. 

[0289] It is preferred from the viewpoint of dry etching resistance that at least one ofR 41 , M $^{41 }$and Q has an alicyclic ring or an aromatic ring. The alicyclic group and the aromatic cyclic group here are the same with the alicyclic group and the aromatic cyclic group as Q described above. 

[0290] The specific examples of the repeating unit (B) are shown below, but the invention is not restricted thereto. 

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