Feb.28,2019  57  US 2019/0064665 Al  [0213]  For the surfactant which is insoluble or substan› tially insoluble in water and soluble in alkaline developer,  reference may be made to JP-A 2008-122932, 2009-098638,  2009-191151, 2009-192784, 2009-276363, 2010-107695,  2010-134012, 2010-250105, and 2011-042789.  [0214]  An appropriate amount of component (F) is Oto 20  parts by weight per 100 parts by weight of the base resin (B).  The lower limit is preferably 0.001 part, and more preferably  0.01 part by weight, whereas the upper limit is preferably 15  parts, and more preferably 10 parts by weight.  Process  EXAMPLE  [0215]  A further embodiment of the invention is a pattern  forming process using the resist composition defined above.  A pattern may be formed from the resist composition using  any well-known lithography process. The preferred process  includes at least the steps of forming a resist film on a  substrate, exposing it to high-energy radiation, and devel› oping it in a developer.  [0216]  Specifically, the resist composition is applied onto  a substrate for integrated circuitry fabrication ( e.g., Si, Si 0 2 ,  SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective  film, etc.) or a substrate for mask circuitry fabrication (e.g.,  Cr, CrO, CrON, MoSi$_{2}$, SiO 2 , etc.) by a suitable coating  technique such as spin coating. The coating is prebaked on  a hotplate at a temperature of 60 to 150°  C. for 1 to 10  minutes, preferably 80 to 140°  C. for 1 to 5 minutes. The  resulting resist film is generally 0.05 to 2 m thick.  [0217]  Through a mask having a desired pattern disposed  over the substrate, the resist film is then exposed to high› energy radiation such as KrF excimer laser, ArF excimer  laser or EUV in an exposure dose preferably in the range of  1 to 200 mJ/cm 2 ,  more preferably 10 to 100 mJ/cm 2 .  Alternatively, pattern formation may be performed by writ› ing with EB directly ina dose of preferably 1 to 300 µC/cm 2 ,  more preferably 10 to 200 µC/cm 2 .  Light exposure may be  done by a conventional lithography process or in some  cases, by an immersion lithography process of providing a  liquid having a refractive index of at least 1.0 between the  projection lens and the resist film. The preferred liquid is  water. In the case of immersion lithography, a protective film  which is insoluble in water may be formed on the resist film.  [0218]  The resist film is then baked (PEB) on a hotplate at  60 to 150°  C. for 1 to 5 minutes, and preferably at 80 to 140°  C. for 1 to 3 minutes. Finally, development is carried out  using as the developer an aqueous alkaline solution, such as  a 0.1 to 5 wt%, preferably 2 to 3 wt%, aqueous solution of  tetramethylammonium hydroxide (TMAH), this being done  by a conventional method such as dip, puddle, or spray  development for a period of0.1 to 3 minutes, and preferably  0.5 to 2 minutes. In this way the desired pattern is formed on  the substrate.  [0219]  While the water-insoluble protective film which is  used in the immersion lithography serves to prevent any  components from being leached out of the resist film and to  improve water slippage at the film surface, it is generally  divided into two types. The first type is an organic solvent› strippable protective film which must be stripped, prior to  alkaline development, with an organic solvent in which the  resist film is not dissolvable. The second type is an alkali› soluble protective film which is soluble in an alkaline  developer so that it can be removed simultaneously with the  removal of solubilized regions of the resist film. The pro› tective film of the second type is preferably of a material  [0224]  Synthesis Examples, Examples and Comparative  Examples are given below by way of illustration and not by  way of limitation. The abbreviation "pbw" is parts by  weight. For all polymers, Mw and  Mn are determined by  GPC versus polystyrene standards using THF solvent. THF  stands for tetrahydrofuran, MEK for methyl ethyl ketone,  MIBK for methyl isobutyl ketone, and DIPE for diisopropyl  ether. Analytic instruments are as shown below.  [0223]  In the organic solvent development, the organic  solvent used as the developer is preferably selected from  2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-hep› tanone, 2-hexanone, 3-hexanone, diisobutyl ketone, meth› ylcyclohexanone, acetophenone, methylacetophenone, pro› pyl acetate, butyl acetate, isobutyl acetate, pentyl acetate,  isopentyl acetate, butenyl acetate, propyl formate, butyl  formate, isobutyl formate, pentyl formate, isopentyl for› mate, methyl valerate, methyl pentenoate, methyl crotonate,  ethyl crotonate, methyl propionate, ethyl propionate, ethyl  3-ethoxypropionate, methyl lactate, ethyl lactate, propyl  lactate, butyl lactate, isobutyl lactate, pentyl lactate, isopen› tyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxy› isobutyrate,  methyl benzoate,  ethyl benzoate,  phenyl  acetate, benzyl acetate, methyl phenylacetate, benzyl for› mate, phenylethyl formate, methyl 3-phenylpropionate, ben› zyl propionate, ethyl phenylacetate, and 2-phenylethyl  acetate. These organic solvents may be used alone or in  admixture of two or more.  [0222]  In the pattern forming process, an alkaline aqueous  solution is often used as the developer. The negative tone  development technique using an organic solvent instead is  also applicable wherein the unexposed region is developed  and dissolved in the organic solvent.  [0221]  A pattern may also be formed by a double pattern› ing process. The double patterning process includes a trench  process of processing an underlay to a 1 :3 trench pattern by  a first step of exposure and etching, shifting the position, and  forming a 1 :3 trench pattern by a second step of exposure for  forming a 1: 1 pattern; and a line process of processing a first  underlay to a 1 :3 isolated left pattern by a first step of  exposure and etching, shifting the position, processing a  second underlay formed below the first underlay by a second  step of exposure through the 1:3 isolated left pattern, for  forming a half-pitch 1:1 pattern.  [0220]  Any desired step may be added to the pattern  forming process. For example, after a photoresist film is  formed, a step of rinsing with pure water (post-soaking) may  be introduced to extract the acid generator or the like from  the film surface or wash away particles. After exposure, a  step of rinsing (post-soaking) may be introduced to remove  any water remaining on the film after exposure.  compnsmg a polymer having a 1,1,1,3,3,3-hexafluoro-2- propanol residue (which is insoluble in water and soluble in  an alkaline developer) as a base in an alcohol solvent of at  least 4 carbon atoms, an ether solvent of 8 to 12 carbon  atoms or a mixture thereof. Alternatively, the aforemen› tioned surfactant which is insoluble in water and soluble in  an alkaline developer may be dissolved in an alcohol solvent  of at least 4 carbon atoms, an ether solvent of 8 to 12 carbon  atoms or a mixture thereof to form a material from which the  protective film of the second type is formed. 