Nov. 24,  2016  25  US 2016/0342090 Al  N-substituted maleimide, acrylonitrile, methacrylonitrile,  vinylnaphthalene, vinylanthracene, indene which may have  a substituent, and a polymerizable monomer having an  alcoholic hydroxyl group substituted with a fluoroalkyl  group or the like at the a-position. Preferred examples of the  substituted styrene include 4-(1-naphthylmethoxy)styrene,  4-benzyloxystyrene,  4-( 4-chlorobenzyloxy)styrene,  3-(1- naphthylmethoxy)styrene, 3-benzyloxy styrene, and 3-(4- chlorobenzyloxy)styrene.  [0156]  The polymer compound (A) may or may not con› tain such other repeating unit, but in the case of containing  such other repeating unit, the content thereof in the polymer  compound (A) is generally 1 mo! % to 20 mo! %, and  preferably 2 mo! % to 10 mo! %, based on the total repeating  units constituting the polymer compound (A).  [0157]  The polymer compound (A) can be synthesized, for  example, by radical, cationic or anionic polymerization of  unsaturated monomers corresponding to respective repeat› ing units. The polymer compound can be also synthesized by  polymerizing a polymer from unsaturated monomers corre› sponding to precursors of respective repeating units, and  modifying the synthesized polymer with a low molecular  compound, thereby converting the precursors into desired  repeating units, in either case, living polymerization such as  living anionic polymerization is preferably used, because the  obtained polymer compound can have a uniform molecular  weight distribution.  [0158]  The weight average molecular weight of the poly› mer compound (A) is preferably 1,000 to 200,000, more  preferably 2,000 to 50,000, and still more preferably 2,000  to 15.000. The polydispersity (molecular weight distribu› tion) (Mw/Mn) of the polymer compound (A) is, in view of  sensitivity, preferably from 1.0 to 1.7, and more preferably  from 1.0 to 1.2. The weight average molecular weight and  the polydispersity of the polymer compound (A) are defined  in terms of polystyrene by GPC measurement.  [0159]  In the present specification, the weight average  molecular weight and polydispersity can be determined, for  example using HLC-8120 (manufactured by Tosoh Corpo› ration), TSK gel Multipore HXL-M (manufactured by Tosoh  Corporation, 7.8 mmIDx30.0 cm) as a colunm, and tetra› hydrofuran (THF) as an eluting solution.  [0160]  In the composition of the present invention, two or  more of these polymer compounds (A) may be mixed and  used.  [0161]  The content of the polymer compound (A) is  preferably 30 mass % to 100 mass %, more preferably 50  mass% to 99.7 mass%, and particularly preferably 70 mass  % to 99.5 mass %, based on the total solid content of the  composition of the present invention.  [0162]  [2] (B) Compound Capable of Generating Acid  Upon Irradiation with Actinic Rays or Radiation  [0163]  The actinic ray-sensitive or radiation-sensitive  resin composition of the present invention further contains  (B) a compound capable of generating an acid upon irra› diation with actinic rays or radiation (hereinafter, sometimes  simply referred to as an "acid generator") as an essential  component. In the present invention, the compound (B)  capable of generating an acid upon irradiation with actinic  rays or radiation may be a low-molecular weight acid  generator capable of generation an acid upon irradiation  with actinic rays or radiation (particularly an electron beam  or extreme ultraviolet rays) or may be an acid-generating  polymer compound. As described above, also preferred is an  [0174]  Examples of the organic anion of  x- in General  Formulae (1) and (2) include a sulfonate anion, a carboxy› late anion, a bis(alkylsulfonyl)amide anion, and a tris(alkyl› sulfonyl)methide anion. The organic anion is preferably an  organic anion represented by the following General Formula  [0173]  Ra$_{1 }$to  Ra$_{3 }$ in General Formula (1) and  Ra$_{4 }$ and  Ras  in General Formula (2) each independently represent an  organic group, but each of at least one of Ra$_{1}$ ,  Ra$_{2}$ ,  or  Ra$_{3 }$ and  at least one of  Ra$_{4 }$ or  Ras  is preferably an aryl group. The  aryl group is preferably a phenyl group or a naphthyl group,  and more preferably a phenyl group.  [0172]  Hereinafter, the sulfonium compound represented  by General Formula (1) and the iodonium compound rep› resented by General Formula (2) will be described in more  detail.  [0171]  x- represents an organic anion.  [0170]  Rau Ra$_{2}$ ,  Ra$_{3}$ ,  Ra$_{4}$ ,  and  Ras  each independently  represent an organic group.  [0169]  In General Formulae (1) and (2),  (2)  (1)  embodiment in which the compound (B) is integrated as one  constituent component of the polymer compound (A), that  is, the polymer compound (A) includes a repeating unit  further containing a group capable of generating an acid  upon irradiation with actinic rays or radiation in the main  chain or side chain.  [0164]  A preferred aspect of the acid generator is an onium  compound. Examples of the onium compound include a  sulfonium salt, an iodonium salt, and a phosphonium salt.  [0165]  Another preferred embodiment of the acid genera› tor is a compound capable of generating a sulfonic acid, an  imide acid, or a methide acid upon irradiation with actinic  rays or radiation. Examples of the acid generator in this  embodiment include a sulfonium salt, an iodonium salt, a  phosphonium salt, oxime sulfonate, and imidosulfonate.  [0166]  The acid generator for use in the present invention  is not limited to a low-molecular weight compound, and a  compound where a group capable of generating an acid upon  irradiation with actinic rays or radiation is introduced into  the main or side chain of a polymer compound may also be  used. Furthermore, in the case where, as described above, a  group capable of generating an acid upon irradiation with  actinic rays or radiation is present in a repeating unit serving  as a copolymerization component of the polymer compound  (A) for use in the present invention, the acid generator (B)  as a molecule different from the polymer compound (A) of  the present invention may be absent.  [0167]  The acid generator is preferably a compound  capable of generating an acid upon irradiation with an  electron beam or extreme ultraviolet rays.  [0168]  In the present invention, the onium compound is  preferably a sulfonium compound represented by the fol› lowing General Formula  (I)  or an iodonium compound  represented by General Formula (2). 