merization process ( also called an oligomer process) may be used. The fluoro-aliphatic compound can be synthesized by the method described in JP-A-2002-90991. 

[0136] The polymer having a fluoro-aliphatic group is preferably a copolymer of a fluoro-aliphatic group-contain› ing monomer with a (poly(oxyalkylene)) acrylate and/or a (poly(oxyalkylene)) methacrylate, and the polymer may have an irregular distribution or may be a block copolymer. Examples of the poly(oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group and a poly (oxybutylene) group. This group may also be a unit having alkylenes differing in the chain length within the same chain, such as block-linked poly(oxyethylene, oxypro› pylene and oxyethylene) andblock-linked poly(oxyethylene and oxypropylene ). Furthermore, the copolymer of a fluoro› aliphatic group-containing monomer with a (poly(oxyalky› lene)) acrylate (or methacrylate) may be not only a binary copolymer but also a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different fluoro-aliphatic group-containing monomers or two or more different (poly(oxyalkylene)) acrylates (or methacrylates). 

[0137] Examples thereof include commercially available surfactants such as Megafac F178, F-470, F-473, F-475, F-476 and F-472 (produced by Dainippon Ink & Chemicals, Inc.), and further include a copolymer of an acrylate (or methacrylate) having a C$_{6}$F $_{13 }$ group with a (poly-( oxyalky› lene )) acrylate ( or methacrylate ), a copolymer of an acrylate ( or methacrylate) having a C$_{6}$F $_{13 }$ group with (poly( oxyeth› ylene )) acrylate (or methacrylate) and (poly-(oxypropy› lene )) acrylate ( or methacrylate ), a copolymer of an acrylate ( or methacrylate) having a C$_{8}$F $_{17 }$ group with a (poly( oxy› alkylene )) acrylate ( or methacrylate ), and a copolymer of an acrylate ( or methacrylate) having a C$_{8}$F $_{17 }$group with (poly› ( oxyethylene )) acrylate (or methacrylate) and (poly(oxypro› pylene)) acrylate (or methacrylate). 

[0138] The amount of the surfactant used is preferably from 0.0001 to 2 mass %, more preferably from 0.001 to 1 mass %, based on the entire amount of the positive resist composition (excluding the solvent). 

## [ 5] Other components 

[0139] The positive resist compos1t10n of the present invention may further contain, if desired, a dye, a photo-base generator and the like. 

## 1. Dye 

[0140] In the present invention, a dye may be used. 

[0141] A suitable dye includes an oily dye and a basic dye. Specific examples thereof include Oil Yellow #101, Oil Yellow #103, Oil Pink #312, Oil Green BG, Oil Blue BOS, Oil Blue #603, Oil Black BY, Oil Black BS, Oil Black T-505 (all produced by Orient Chemical Industries Co., Ltd.), Crystal Violet (CI42555), Methyl Violet (CI42535), Rhodamine B (CI45170B), Malachite Green (CI42000) and Methylene Blue (CI52015). 

## 2. Photo-base generator 

[0142] Examples of the photo-base generator which can be added to the composition of the present invention include the compounds described in JP-A-4-151156, JP-A-4- 162040, JP-A-5-197148, JP-A-5-5995, JP-A-6-194834, JP-A-8-146608, JP-A-10-83079 and European Patent 622, 

682. Specific examples of the photo-base generator which can be suitably used include 2-nitrobenzyl carbamate, 2,5- dinitro benzy lcyclohexyl carbamate, N-cyclohexy 1-4-meth› y lpheny !sulfonamide and 1, 1-dimethy 1-2-pheny lethy 1-N› isopropy l carbamate. Such a photo-base generator is added for the purpose of improving the resist profile or the like. 

## 3. Solvents 

[0143] The resist composition of the present invention is dissolved in a solvent capable of dissolving respective components described above and then coated on a support. Usually, the concentration is, in terms of the solid content concentration of all resist components, preferably from 2 to 30 mass %, more preferably from 3 to 25 mass %. 

[0144] Preferred examples of the solvent used here include ethylene dichloride, cyclohexanone, cyclopentanone, 2-hep› tanone, y-butyrolactone, methyl ethyl ketone, ethylene gly› col monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene gly› col monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N,N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone and tetrahydrofuran. One of these sol› vents is used alone, or several species thereof are mixed and used. 

[0145] The positive resist composition of the present invention is coated on a substrate to form a thin film. The thickness of this coating film is preferably from 0.05 to 4.0 µm. 

[0146] In the present invention, a commercially available inorganic or organic antireflection film may be used, if desired. Furthermore, an antireflection film may be used by coating it as an underlayer of the resist. 

[0147] The antireflection film used as the underlayer of the resist may be either an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon and amorphous silicon, or an organic film type comprising a light absorbent and a polymer material. The former requires equipment for the film formation, such as vacuum deposition apparatus, CVD apparatus and sputtering appa› ratus. Examples of the organic antireflection film include a film comprising a diphenylamine derivative and formalde› hyde-modified melamine resin condensate, an alkali-soluble resin and a light absorbent described in JP-B-7-69611 (the term "JP-B" as used herein means an "examined Japanese patent publication"), a reaction product of a maleic anhy› dride copolymer and a diamine-type light absorbent described in U.S. Pat. No. 5,294,680, a film comprising a resin binder and a methylolmelamine-based heat crosslink› ing agent described in JP-A-6-118631, an acrylic resin-type antireflection film containing a carboxylic acid group, an epoxy group and a light absorbing group within the same molecule described in JP-A-6-118656, a film comprising methylolmelamine and a benzophenone-based light absor› bent described in JP-A-8-87115, and a film obtained by adding a low molecular light absorbent to a polyvinyl alcohol resin described in JP-A-8-179509. 

[0148] Also, the organic antireflection film may be a commercially available organic antireflection film such as 

