155  US 9,323,153 B2  156  more preferably, the repeating unit contains no fluorine atom.  In the case where the resin (Ab) has a repeating unit (B), the  repeating unit is a repeating unit other than the repeating unit  (B), and the content of the fluorine atom-containing repeating  unit is more preferably  1  % by mole or less, and most prefer- ably, the repeating unit contains no fluorine atom.  [3] Compound Capable of Generating an Acid by Irradia› tion with Actinic Rays or Radiation  The composition of the present invention may further 10  include a compound capable of generating an acid by irradia› tion with actinic rays or radiation ( also hereinafter referred to  a "photo-acid generator").  As such a photo-acid generator, photoinitiators for photo› cation polymerization, photoinitiators for photo-radical poly› merization,  photodecoloring  agents,  photo-discoloring  agents, known compounds that generate an acid by irradiation  with actinic rays or radiation, which are used in microresists,  or the like, mixtures thereof may be suitably selected and  used. Examples thereof include onium salts such as a sulfo› nium salt and an iodonium salt, and diazodisulfone com› pounds such as bis(alkylsulfonyl)diazomethane.  Preferred examples of the photo-acid generator include the  compounds represented by the following general formulae  (ZI), (ZII)  and  (ZIII).  In the general formula (ZI), R$_{201}$, R$_{202 }$and R$_{203 }$each inde› pendently represent an organic group. The number of carbon  atoms of the organic group as R$_{20}$ i, R $_{202 }$and R$_{203 }$ is, for  example, from  1  to 30, and preferably from  1  to 20.  Two members out of R$_{201 }$to R$_{203 }$may be bonded to each  other via a single bond or a connecting group to form a ring  structure. In this case, examples of the connecting group  include an ether bond, a thioether bond, an ester bond, an  amide bond, a carbonyl group, a methylene group, and an  ethylene group. Examples of the group formed by combining  two members out of R$_{20}$1 to R$_{203 }$ include alkylene groups  such as a butylene group and a pentylene group.  x- represents a non-nucleophilic anion. Examples of x- include a sulfonate anion, a bis(alkylsulfonyl)amide anion, a  tris(alkylsulfonyl)methide anion, BF  4 -, PF 6  -, and SbF  6 -. x- is preferably an organic anion containing a carbon atom.  Preferred examples of the organic anions include organic  anions represented by the following AN! to AN3.  [Chem. 33]  -continued  In the formulae AN! to AN3, Rc$_{1 }$ to Rc$_{3 }$ each indepen› dently represent an organic group. Examples of the organic  group include an organic group having  1  to 30 carbon atoms,  and the organic group is preferably an alkyl group, an aryl  group, or a group formed by connecting a plurality of these  groups through a connecting group. Examples of the connect› ing group include a single bond, -0-, -CO$_{2}$ -,  -S-,  -SO$_{3}$-and-SO$_{2}$N(Rd$_{1}$)-. Here, Rd$_{1 }$represents a hydro› gen atom or an alkyl group and may form a ring structure  together with the alkyl group or aryl group to which Rd$_{1 }$ is  bonded.  The organic group of Rc$_{1 }$ to Rc$_{3 }$ may be an alkyl group  substituted with a fluorine atom or a fluoroalkyl group at the  I-position, or a phenyl group substituted with a fluorine atom  or a fluoroalkyl group. By containing a fluorine atom or a  fluoroalkyl group, the acidity of an acid generated by irradia› tion with light can be increased. This can improve the sensi› tivity of an actinic ray-sensitive or radiation-sensitive resin  composition. Incidentally, each ofRc$_{1 }$to Rc$_{3 }$ may be bonded  to another alkyl group, aryl group, or the like to form a ring  structure.  Furthermore, preferred examples ofx- include a sulfonate  anion represented by the following general formula (SAi) or  (SA2).  In the formula (SAi ),  In the formula (SA2),  Xf’ s each independently represent a fluorine atom, or an  alkyl group with at least one hydrogen atom being sub› stituted with a fluorine atom.  Ar $_{1 }$represents an aryl group, and may further have a sub› stituent other than a -(D-B) group.  D represents a single bond or a divalent connecting group.  This divalent connecting group is an ether group, a thio› ether group, a carbonyl group, a sulfoxide group, a sul› fone group, a sulfonic acid ester group, or an ester group.  B represents a hydrocarbon group.  (ZII)  (ZIii)  AN2  AN3  n represents an integer of  1  or more. n is preferably from  1  to  4,  more preferably from 2 to 3, and most preferably 3.  [Chem. 35]  (D-B)n  (SA 1)  [Chem. 34]  [Chem. 36]  (SA2) 