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is 0, 1, 2, 3 or 4. R$^{329 }$is hydrogen, methyl, ethyl or phenyl. X is a nitrogen atom or CR 330 . Y is a nitrogen atom or CR 331 . Z is a nitrogen atom or CR 332 . R 330 , R $^{331 }$and R$^{332 }$are each independently hydrogen, methyl or phenyl. Alternatively, a pair of R$^{330 }$and R$^{331 }$or a pair of R$^{331 }$and R$^{332 }$may bond 5 together to form a CcC$_{20 }$ aromatic ring or C$_{2}$ -C$_{20 }$hetero› aromatic ring with the carbon atom to which they are attached. 

Further included are organic nitrogen-containing com› pounds of7-oxanorbornane-2-carboxylic ester structure hav› ing the general formula (D)-15. 

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Herein R 333 is hydrogen or a straight, branched or cyclic C$_{1 }$-C$_{10 }$alkyl group. R$^{334 }$and R$^{335 }$are each independently a C$_{1 }$-C$_{20 }$ alkyl group, CcC$_{20 }$ aryl group or C$_{7}$-C$_{20 }$ aralkyl group, which may contain one or more polar functional groups selected from among ether, carbonyl, ester, alcohol, sulfide, nitrile, amine, imine, and amide and in which some hydrogen atoms may be replaced by halogen atoms. R$^{334 }$and R 335 , taken together, may form a heterocyclic or hetero-aro› matic ring of 2 to 20 carbon atoms with the nitrogen atom to which they are attached. 

Also useful as the basic component are basic compounds of amine oxide structure which is oxidized on nitrogen. Examples include tris(2-(methoxymethoxy)ethyl)amine oxide, 2,2’ ,2"-nitrilotriethylpropionate N-oxide, and N-2-( (2- methoxyethoxy )methoxyethy lmorpholine N-oxide. 

The organic nitrogen-containing compounds may be used alone or in admixture of two or more. The organic nitrogen› containing compound (D) is preferably formulated in an amount of0.001 to 4 parts, and especially 0.01 to 2 parts by weight, per 100 parts by weight of the entire base resin. Less than 0.001 part of the nitrogen-containing compound achieves no or little addition effect whereas more than 4 parts may result in too low a sensitivity. 

Surfactant 

Optionally, the resist composition of the invention may further comprise a surfactant which is commonly used for facilitating the coating operation. The surfactant may be added in conventional amounts so long as this does not com› promise the objects of the invention. 

Illustrative, non-limiting examples of the surfactant include nonionic surfactants, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxy› ethylene stearyl ether, polyoxyethylene cetyl ether, and poly› oxyethylene oleyl ether, polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenol ether and polyoxyeth› ylene nonylphenol ether, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, and sorbitan monostearate, and polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyeth› ylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and poly› oxyethylene sorbitan tristearate; fluorochemical surfactants such as EFTOP EF301, EF303 and EF352 (JEMCO Inc.), Megaface F171, Fl 72, Fl 73, ROS, R30, R90 and R94 (DIC Corp.), Fluorad FC-430, FC-431, FC-4430 and FC-4432 

(Sumitomo 3M Co., Ltd.), Asahiguard AG710, Surflon S-381, S-382, S-386, SC101, SC102, SC103, SC104, SC105, SC106, KH-10, KH-20, KH-30andKH-40 (Asahi Glass Co., Ltd.); organosiloxane polymers KP341, X-70-092 and X-70- 093 (Shin-Etsu Chemical Co., Ltd.), acrylic acid or meth› acrylic acid Polyflow No. 75 and No. 95 (Kyoeisha Ushi Kagaku Kogyo Co., Ltd.). 

Additional useful surfactants include partially fluorinated oxetane ring-opened polymers having the structural formula (surf-I). 

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It is provided herein that R, Rf, A, B, C, m’, and n’ are applied to only formula (surf-1), independent of their descriptions other than for the surfactant.Risa di- to tetra-valent C$_{2}$-C$_{5 }$ aliphatic group. Exemplary divalent groups include ethylene, 1,4-butylene, 1,2-propylene, 2,2-dimethyl-1,3-propylene and 1,5-pentylene. Exemplary tri- and tetra-valent groups are shown below. 

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Herein the broken line denotes a valence bond. These formu- lae are partial structures derived from glycerol, trimethylol ethane, trimethylol propane, and pentaerythritol, respec› tively. Of these, 1,4-butylene and 2,2-dimethyl-1,3-propy› lene are preferably used. 

Rf is trifluoromethyl or pentafluoroethyl, and preferably trifluoromethyl. The letter m’ is an integer of Oto 3, n’ is an integerofl to 4, and the sum of m’ andn’, which represents the valence of R, is an integer of 2 to 4. A is equal to 1, B is an integer of 2 to 25, and C is an integer ofO to 10. Preferably, B is an integer of 4 to 20, and C is 0 or 1. Note that the above structural formula does not prescribe the arrangement of respective constituent units while they may be arranged either in blocks or randomly. For the preparation of surfactants in the form of partially fluorinated oxetane ring-opened poly- mers, reference should be made to U.S. Pat. No. 5,650,483, for example. 

Of the foregoing surfactants, FC-4430, Surflon 5-381, KH-20, KH-30, and oxetane ring-opened polymers of for› mula (surf-I) are preferred. These surfactants may be used alone or in admixture. 

In the resist composition, the surfactant is preferably com› pounded in an amount ofup to 2 parts, and especially up to 1 

