US 10,781,276 B2  17  18  surfactant, a filler, a pigment, an antistatic agent, a flame  retardant, a light stabilizer, an antioxidant, an ion scavenger  and a solvent.  The fluorine-containing water-repellent polymer includes  that commonly used in an immersion exposure process. A  fluorine atom content of the fluorine-containing water-re› pellent polymer is preferably higher than that of the above  mentioned polymer. Thereby, when a resist film is formed by  using the resist composition, the fluorine-containing water› repellent polymer can be localized to a surface of the resist  film due to water repellency of the fluorine-containing  water-repellent polymer.  A method for preparing the resist composition in an  embodiment of the present invention is not limited, and the  resist composition may be prepared by a known method  such as mixing, dissolving or kneading the polymer and  other optional components.  The polymer may be synthesized by proper polymerizing  of the monomers constituting the unit A and the unit B, and  if necessary, the monomers constituting other units, accord› ing to a usual method. However, the method for preparing  the polymer of the present invention is not limited thereto.  <4> Method for Manufacturing Device  An embodiment of the present invention is a method for  manufacturing a device, comprising: a resist film forming  step of forming the resist film on a substrate using the resist  composition; a photolithography step of exposing the resist  film to the particle beam or the electromagnetic wave; and  a pattern forming step of developing an exposed resist film  to obtain a photoresist pattern.  Examples of the particle beam or the electromagnetic  wave used for exposure in the photolithography step include  an electron beam and EUV, respectively.  The exposure dose is, depending on a type and content of  each component in the photocurable composition, and the  film thickness of the coating film and the like, preferably 1  J/cm 2  or less or 1000 µC/cm 2  or less.  When the resist composition comprises the sensitizer unit  (the unit  C)  in the polymer or the sensitizer compound, a  second exposure to an ultraviolet ray or the like is preferably  performed after irradiation with the particle beam or the  electromagnetic wave.  Hereinafter, some embodiments of the present invention  will be described in more detail by examples, but the present  invention is not limited by these examples.  7.0 g of dibenzothiophene is dissolved in 21.0 g of formic  acid and set to 35°  C. 4.1 g of 35% by mass of aqueous  hydrogen peroxide is added dropwise thereto and the mix› ture is stirred at 25° C. for 5 hours. After cooling, the  reaction solution is added dropwise to 50 g of pure water to  precipitate. The precipitated solid is filtered, washed twice  with 20 g of pure water, and then recrystallized using  acetone. After filtration and drying, 7.6 g of dibenzothio› phene-9-oxide is obtained.  4.0 g of dibenzothiophene-9-oxide obtained in Synthesis  Example 1 and 2.8 g of phenol are dissolved in 19 g of  methanesulfonic acid and set to 25°  C. 1.5 g of diphospho› rous pentoxide is added thereto and the mixture is stirred at  room temperature for 15 hours. Thereafter, 60 g of pure  water is added thereto, the mixture is stirred for further 5  minutes, and then washed twice with 20 g of ethyl acetate.  After phase separation, and 3.9 g of potassium trifluo› romethanesulfonate and 30 g of methylene chloride are  added to the obtained aqueous layer, and the mixture is  stirred at room temperature for 2 hours. Thereafter, phase  separation is performed, and the obtained organic layer is  washed four times with 40 g of pure water. The combined  organic layer is concentrated and added dropwise to 100 g  of diisopropyl ether to precipitate a solid. The precipitated  solid is filtered and dried to obtain 5.6 g of 9-( 4-hydroxy› phenyl)dibenzothiophenium-trifluoromethanesulfonate.  EXAMPLES  <3> Method for Preparing the Resist Composition  <Synthesis of Compound Al Constituting Unit A>  (Synthesis Example 1) Synthesis of  dibenzothiophene-9-oxide  [Chem.13]  0  II  s  s  <SQ~<SQ  (Synthesis Example 2) Synthesis of 9-(4-hydroxy› phenyl)dibenzothiophenium-trifluoromethanesul› fonate  [Chem.14]  0  OH  II  6  s  <So’  - OH  ¢  s+ 