32  US 7,217,493 B2  31  Further, commercially available surfactants as described  below can also be used as they are.  Examples of the commercially available surfactant that  can be used include fluorine based surfactants or silicon  based surfactants, for example, Eftop EF301 or Eftop EF303  (manufactured by Jemco Inc.), Fluorad FC430 or Fluorad  FC431 (manufactured by Sumitomo 3M Limited), Megafac  F171, Megafac F173, Megafac F176, Megafac F189 or  Megafac ROS (manufactured by Dainippon Ink and Chemi› cals, Inc.), Surflon S-382, Surflon SCIO!, Surflon SC102,  Surflon SC103, Surflon SC104, Surflon SC105 or Surflon  SC106 (manufactured by Asahi Glass Co., Ltd.) and Troysol  S-366 (manudactured by Troy Chemical Industries, Inc.).  Also, Polysiloxane Polymer KP-341 (manufactured by Shin- Etsu Chemical Co., Ltd.) can be used as the silicon based  surfactant.  Besides the above-described known surfactants, surfac› tants using a polymer containing a fluoro aliphatic group  derived from a fluoro aliphatic compound produced by a  telomerization process (also called a telomer process) or an  oligomerization process (also called an oligomer process)  can also be used as the surfactant. The fluoro aliphatic  compound can be synthesized according to the method  described in JP-A-2002-90991.  As the polymer containing a fluoro aliphatic group,  copolymers of a fluoro aliphatic group-containing monomer  and a (poly(oxyalkylene)) acrylate and/or a (poly(oxyalky› lene)) methacrylate are preferred. The copolymer may be in  the form of a random copolymer or a block copolymer.  Examples of the poly(oxyalkylene) group include a poly  ( oxyethylene) group, a poly( oxypropylene) group and a  poly(oxybutylene) group. Also, units containing alkylenes  having a different chain length in the same chain, for  example, a poly(block connecting body of oxyethylene,  oxypropylene and oxyethylene) group and a poly(block  connecting body of oxyethylene and oxypropylene) group  may be used. Further, the copolymer of a fluoro aliphatic  group-containing monomer and a (poly(oxyalkylene)) acry› late ( or methacrylate) includes not only binary copolymers  but also ternary or multi-component copolymers prepared by  copolymerization of two or more different fluoro aliphatic  group-containing monomers or two and more different (poly  (oxyalkylene)) acrylates (or methacrylates).  Examples of commercially available surfactants include  Megafac F178, Megafac F-470, Megafac F-473, Megafac  F-475, Megafac F-476 or Megafac F-472 (manufactured by  Dainippon Ink and Chemicals, Inc.). Also, copolymers of a  C$_{6}$F $_{13 }$ group-containing acrylate ( or methacrylate) and a  (poly(oxyalkylene)) acrylate (or methacrylate), copolymers  of a C$_{6}$F $_{13 }$ group-containing acrylate ( or methacrylate ),  (poly(oxyethylene)) acrylate (or methacrylate) and (poly  ( oxypropylene )) acrylate ( or methacrylate ), copolymers of a  C$_{8}$F $_{17 }$ group-containing acrylate ( or methacrylate) and a  (poly(oxyalkylene)) acrylate (or methacrylate), and copoly- mers of a C$_{8}$F $_{17 }$group-containing acrylate ( or methacrylate ),  (poly(oxyethylene)) acrylate (or methacrylate) and (poly  (oxypropylene)) acrylate (or methacrylate) can be exempli› fied.  An  amount of the surfactant used is preferably from  0.0001 to 2% by weight, and more preferably from 0.001 to  1 % by weight based on the total amount of the positive resist  composition (excluding a solvent).  The positive resist composition of the present invention  may further contain other components, for example, a dye,  a photo-base generator or the like, if desired.  Examples  of such  surfactants  include  surfactants  described in JP-A-62-36663, JP-A-61-226746, JP-A-61- 226745, JP-A-62-170950, JP-A-63-34540, JP-A-7-230165,  JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, JP-A-2002- 277862 and U.S. Pat. Nos. 5,405,720, 5,360,692, 5,529,881,  5,296,330, 5,436,098, 5,576,143, 5,294,511 and 5,824,451.  It is preferred to contain either one or two or more kinds  of fluorine based and/or silicon based surfactants (including  a fluorine based surfactant, a silicon based surfactant and a  surfactant containing both a fluorine atom and a silicon  atom) as the surfactant in view of improving film forming  property, reducing development defect and increasing wet- tability of a developing solution on the resist film.  The surfactants may be used individually or in combina› tion of two or more thereof.  An  amount of the surfactant is ordinarily not more than 2  parts by weight, and preferably not more than 1 part by  weight based on 100 parts by weight of the solid content of  the resist composition of the present invention.  Specific examples of the surfactant include nonionic  surfactants, for example, polyoxyethylene alkyl ethers (for  example, polyoxyethylene lauryl ether, polyoxyethylene  stearyl ether, polyoxyethylene cetyl ether or polyoxyethyl› ene oleyl ether), polyoxyethylene alkylaryl ethers (for  example, polyoxyethylene octylphenyl ether or polyoxyeth› ylene nonylphenyl ether), polyoxyethylene-polyoxypropy- lene block copolymers, sorbitan fatty acid esters (for  example, sorbitan monolaurate, sorbitan monopalmitate,  sorbitan monostearate, sorbitan monooleate, sorbitan tri› oleate or sorbitan tristearate) and polyoxyethylene sorbitan  fatty acid esters (for example, polyoxyethylene sorbitan  monolaurate,  polyoxyethylene  sorbitan monopalmitate,  polyoxyethylene sorbitan mono-stearate, polyoxyethylene  sorbitan trioleate or poly-oxyethylene sorbitan tristearate );  fluorine based surfactants or silicon based surfactants, for  example, Eftop EF301, Eftop EF303 or Eftop EF352 (manu- factured by Jemco Inc.), Megafac Fl 71 or Megafac Fl 73  (manufactured by Dainippon Ink and Chemicals, Inc.), Fluo› rad FC430 or Fluorad FC431 (manufactured by Sumitomo  3M Limited), Asahi Guard AG710, Surflon S-382, Surflon  SCIO!, Surflon SC102, Surflon SC103, Surflon SC104,  Surflon SC105 or Surflon SC106 (manufactured by Asahi  Glass Co., Ltd.) and Troysol S-366 (manufactured by Troy  Chemical Industries, Inc.); organosiloxane polymers (for  example, KP341 manufactured by Shin-Etsu Chemical Co.,  Ltd.) and acrylic acid based or methacrylic acid based  (co)polymers (for example, Polyflow No. 75 or Polyflow  No. 95 manufactured by Kyoeisha Chemical Co., Ltd.).  In the present invention, a surfactant can be used, and the  use of surfactant is preferred from the viewpoint of film  forming property, adhesion of pattern, reduction of devel› opment defect or the like.  Aratio of the compound of Component (B)/the compound  of Component (D) by weight is ordinarily from 99.9/0.1 to 10  50/50, preferably 99/1 to 60/40, and particularly preferably  from 98/2 to 70/30.  An  amount of the compound of Component (D) in the  positive resist composition of the present invention is pref› erably from 0.01 to 10% by weight, more preferably from  0.03 to 5% by weight, and particularly preferably from 0.05  to 3% by weight based on the solid content of the resist  composition. The compounds that generate a carboxylic acid  upon irradiation of an actinic ray or radiation may be used  individually or as a mixture of two or more thereof.  [ 6] Other Components  [5] Surfactant 