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DUV-30 Series, DUV-40 Series (produced by Brewer Sci› ence, Inc.), AR-2, AR-3 andAR-5 (produced by Shipley Co., Ltd.). 

[0149] In the production or the like of a precision inte› grated circuit device, the step of forming a pattern on a resist film is performed by coating the positive resist composition of the present invention on a substrate (for example, a silicon/silicon dioxide-coated substrate, a glass substrate, an ITO substrate or a quartz/chromium oxide-coated substrate) to form a resist film, irradiating thereon actinic rays or radiation such as KrF excimer laser light, electron beam or EUV light, and then subjecting the resist film to heating, development, rinsing and drying, whereby a good resist pattern can be formed. 

[0150] The alkali developer which can be used in the development is an aqueous solution of an alkali (usually, 0.1 to 20 mass %) such as inorganic alkalis (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia), primary amines (e.g., ethylamine, n-propylamine), secondary amines (e.g., diethylamine, di-n-butylamine), tertiary amines (e.g., triethylamine, methyldiethylamine), alcohol amines (e.g., dimetylethanolamine, triethanolamine), quaternary ammo› nium salts (e.g., tetramethylannnonium hydroxide, tetra› ethylammonium hydroxide, choline) and cyclic amines ( e.g., pyrrole, piperidine ). This aqueous solution of an alkali may be used after adding thereto alcohols such as isopropyl alcohol or a surfactant such as nonionic surfactant in an appropriate amount. 

[0151] Among these developers, preferred are a quater› nary ammonium salt, more preferred are tetramethylammo› nium hydroxide and choline. 

[0152] The pH of the alkali developer is usually from 10 to 15. 

[0153] The present invention is described in greater detail below by referring to Examples, but the present invention should not be construed as being limited thereto. In the following, Resins A-1 to A-20 correspond to Resins (1) to (20) set forth above. (Synthesis Example 1: synthesis of Resin A-1) 

[0154] Acetoxystyrene, styrene and 2-methyl-2-adaman› tyl cinnamate were charged at a ratio of 60/20/20 (by mo!) and dissolved in tetrahydrofuran to prepare 100 mL of a solution having a solid content concentration of 20 mass %. Subsequently, 2 mo! % of polymerization initiator V-65 (produced by Waka Pure Chemical Industries, Ltd.) was added thereto and the resulting solution was added dropwise to 10 ml oftetrahydrofuran heated at 60° C., over 4 hours in a nitrogen atmosphere. After the completion of dropwise addition, the reaction solution was heated for 4 hours, and 1 mo! % of V-65 was again added, followed by stirring for 4 hours. After the completion of reaction, the reaction solution was cooled to room temperature and then crystallized in 3 L of hexane, and the precipitated white powder was collected by filtration. 

[0155] The compositional ratio of the polymer determined from C$^{13}$NMR was 58/20/22 (by mo!). Also, the weight average molecular weight determined from GPC was 9,500 in terms of the standard polystyrene. 

## EXAMPLES 

[0156] This polymer was dissolved in 100 ml of acetone, 5 ml of hydrochloric acid was then added thereto and after stirring 1 hour, distilled water was added to precipitate a polymer. The precipitate was washed with distilled water and dried under reduced pressure. Furthermore, the polymer was dissolved in 100 ml of ethyl acetate and after adding hexane, the polymer precipitated was dried under reduced pressure to obtain a powder form of the polymer. The weight average molecular weight of this powder determined by GPC was 10,000 in terms of the standard polystyrene. 

[0157] The resins shown in Table 1, having structures set forth above, were synthesized in the same manner as in Synthesis Example 1. In Table 1, the molar ratio of repeating units is a molar ratio of repeating units starting from the left in the structure shown above. 

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[0158] Incidentally, Resin C-1 of Comparative Example is a p-hydroxystyrene-styrene-tert-butyl acrylate copolymer (molar ratio: 60/20/20) having a weight average molecular weight of 10,000 and a dispersity of 2.28. 

[0159] The sulfonic acid generators and carboxylic acid generators used in Examples all were synthesized by a known synthesis method such as synthesis method described in JP-A-2002-27806. 

[0160] 

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[0161] These components were dissolved in 8.8 g of propylene glycol monomethyl ether acetate, and 0.003 g of D-1 (see below) as the organic basic compound and 0.001 g ofMegafac Fl 76 (produced by Dainippon Ink & Chemicals, Inc., hereinafter simply referred to as "W-1") as the surfac› tant were further added thereto and dissolved. The obtained 

## Example 1 

