[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 

[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 

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. 

[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. 

[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. 

[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. 

[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. 

[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. 

## EXAMPLE 

