38  US 9,069,246 B2  37  alkali-soluble groups not protected by a group capable of  leaving by an action of an acid. The content ratio is preferably  from 0.01 to 0.7, more preferably from 0.05 to 0.50, still more  preferably from 0.05 to 0.40.  In the case of irradiating the composition of the present  invention with ArF excimer laser light, the resin preferably  has a monocyclic or polycyclic alicyclic hydrocarbon struc› ture. Hereinafter, this resin is referred to as "alicyclic hydro› carbon-based acid-decomposable resin".  The alicyclic hydrocarbon-based acid-decomposable resin  is preferably a resin containing at least one repeating unit  selected from the group consisting of a repeating unit having  an alicyclic hydrocarbon-containing partial structure repre› sented by the following formulae (pl) to (p V), and a repeating  unit represented by the following formula (II-AB):  In formula (II-AB), each of Ru’ and R$_{12}$’ independently  represents a hydrogen atom, a cyano group, a halogen atom or  an alkyl group.  Z’ represents an atomic group necessary for forming an  alicyclic structure together with two carbon atoms (C-C) to  which Z’ is bonded.  Formula (II-AB) is preferably the following formula (II› ABl) or (II-AB2):  (II-AB)  [Chem.IS]  [Chem.17]  [Chem.19]  The cycloalkyl group ofR$_{12 }$to R 25  or the cycloalkyl group  formed by Z together with the carbon atom may be a mono- cyclic cycloalkyl group or a polycyclic cycloalkyl group.  Specific examples thereof include a group having a monocy› clo, bicyclo, tricyclo or tetracyclo structure and having a  Each of  R$_{22 }$ to R 25  independently represents a hydrogen  atom, a linear or branched alkyl group having a carbon num› ber of 1 to 4, or a cycloalkyl group, provided that at least one  ofR$_{22 }$to  R$_{25 }$ represents a cycloalkyl group. R$_{23 }$and R 24  may  combine with each other to form a ring structure.  Each of  R$_{1 }$ 7  to R$_{21 }$ independently represents a hydrogen  atom, a linear or branched alkyl group having a carbon num› ber of 1 to 4, or a cycloalkyl group, provided that at least one  ofR 17  to  R$_{21 }$ represents a cycloalkyl group and that either R 19  or  R$_{21 }$ represents a linear or branched alkyl group having a  carbon number of  1 to 4 or a cycloalkyl group.  In formulae (pl) to (p V), the alkyl group of R$_{12 }$to R 25  is  preferably a linear or branched alkyl group having a carbon  number of 1 to 4, and examples thereof include a methyl  group, an ethyl group, a propyl group, an n-butyl group, a  sec-butyl group, and a tert-butyl group.  n represents O or 1.  In formulae (II-AB!) and (II-AB2), each of R$_{13}$’ to R 16 ’  independently represents a hydrogen atom, a halogen atom, a  cyano group, a hydroxyl group, -COOH, ----COOR 5 , a  group capable of decomposing by an action of an acid,  ----C(=O)-X-A’-R$_{17}$ ’,  an alkyl group or a cycloalkyl group.  Here, R 5  represents an alkyl group, a cycloalkyl group or a  group having a lactone structure. X represents an oxygen  atom,  a  sulfur  atom,  -NH-,  -NHSO 2 - or  -NHSO 2 NH-. A’ represents a single bond or a divalent  linking group. R 1  / represents -COOH, -COOR 5 , ----CN, a  hydroxyl group, an alkoxy group, ----CO-NH-R 6 , -CO› NH-SO2-R6 or a group having a lactone structure, wherein  R 6  represents an alkyl group or a cycloalkyl group. At least  two members ofR$_{13}$’ to R 16 ’ may combine with each other to  form a ring structure.  Each of  R$_{12 }$ to R 16  independently represents a linear or  branched alkyl group having a carbon number of 1 to 4 or a  cycloalkyl group, provided that at least one of  R$_{12 }$ to  R$_{14 }$ represents a cycloalkyl group and that either R 15  or R 16  rep› resents a cycloalkyl group.  In formulae (pl) to (p V), Ru represents a methyl group, an  ethyl group, ann-propyl group, anisopropyl group, ann-butyl  group, an isobutyl group or a sec-butyl group. Z represents an  atomic group necessary for forming a cycloalkyl group  together with the carbon atom.  (11-ABl)  (II-AB2)  (pV)  R22  R23  0  I  I  II  R24  R2s  (p!V)  R11  I  -.c•---_  ’, __ z  (pl) 