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wherein R 1 is hydrogen, or a straight, branched or cyclic C$_{1 }$-C$_{30 }$ alkyl, CcC$_{30 }$ aryl, C$_{7}$-C$_{30 }$ aralkyl, C$_{2}$-C$_{30 }$ alkenyl, C$_{2}$ -C$_{10 }$alkenyl, or C$_{4}$ -C$_{12 }$heterocyclic-bearing group, or a combination of such groups, which group may contain a hydroxyl, mercapto, carboxyl, ether, thio ether, ester, sulfonic acid ester, sulfonyl, lactone ring, carbonyl, cyano, nitro, halo- gen, trifluoromethyl, amide, imide, sulfonamide, carbonate, sulfide, -N=CR---0-, -N=CR-S-, or N-O› N=moiety, or R $^{1 }$may be an acid labile group; R is hydrogen, mercapto, hydroxyl or C$_{1 }$-C$_{3 }$ alkyl, or may bond with the nitrogen atom in formula (1) to form a ring; R $^{2 }$and R$^{3 }$each are hydrogen, a straight or branched C$_{1 }$-C$_{4 }$ alkyl group or C$_{2}$-C$_{4 }$ alkenyl group, or R$^{2 }$andR$^{3 }$may bond together to form a ring with the carbon atom to which they are attached; R 4 , Rs and R 6 are each independently a straight, branched or cyclic C$_{1 }$-C$_{12 }$alkyl, alkenyl, oxoalkyl or oxoalkenyl group, CcC$_{20 }$ aryl, C$_{7}$ -C$_{12 }$aralkyl or aryloxoalkyl group, in which at least one hydrogen atom may be substituted by an ether, ester, carbonyl, carbonate, hydroxyl, carboxyl, halogen, cyano, amide, nitro, sultone, sulfonic acid ester, sulfone moiety, or sulfonium salt-containing substituent, R 4 and Rs may bond together to form a ring with the sulfur atom to which they are attached; R$^{7 }$and R $^{8 }$each are a C$_{6}$-C$_{20 }$aryl group which may contain a straight, branched or cyclic C$_{1 }$-C$_{10 }$alkyl or alkoxy moiety, and mis an integer of 2 to 8. 

13. The resist composition of claim 12 wherein the base polymer further comprises recurring units (al) derived from (meth)acrylate, styrenecarboxylic acid or vinylnaphthalen› ecarboxylic acid having an acid labile group substituted thereon, or recurring units (a2) derived from hydroxystyrene having an acid labile group substituted thereon, as repre› sented by the general formula (2): 

wherein R 9 and R 11 are each independently hydrogen or methyl, Xis a single bond, a C$_{1 }$-C$_{12 }$linking group hav› ing an ester moiety or lactone ring, phenylene group or naphthylene group, Y is a single bond or ester group, and R $^{10 }$and R $^{12 }$are each independently an acid labile group. 

14. A process for forming a pattern comprising the steps of applying a resist composition onto a substrate, baking to form a resist film, exposing the resist film to ArF excimer laser radiation of 193 nm wavelength or KrF excimer laser radia- tion of 248 nm wavelength, and developing the exposed film with a developer, 

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-continued 

wherein the resist composition comprises a base polymer and a sulfonium salt having the general formula (1 )-1 or a iodonium salt having the general formula (1)-2, 

wherein R 1 is hydrogen, or a straight, branched or cyclic C$_{1 }$-C$_{30 }$ alkyl, CcC$_{30 }$ aryl, C$_{7}$ -C$_{30 }$ aralkyl, C$_{2}$ -C$_{30 }$ alkenyl, C$_{2}$-C$_{10 }$ alkenyl, or C$_{4}$ -C$_{12 }$heterocyclic-bearing group, or a combination of such groups, which group may contain a hydroxyl, mercapto, carboxyl, ether, thio ether, ester, sulfonic acid ester, sulfonyl, lactone ring, carbonyl, cyano, nitro, halo› gen, trifluoromethyl, amide, imide, sulfonamide, carbonate, sulfide, -N=CR---0-, -N=CR-S-, or N-O› N=moiety, or R $^{1 }$may be an acid labile group; R is hydrogen, mercapto, hydroxyl or C$_{1 }$-C$_{3 }$ alkyl, or may bond with the nitrogen atom in formula (1) to form a ring; R $^{2 }$and R$^{3 }$each are hydrogen, a straight or branched C$_{1 }$-C$_{4 }$ alkyl group or C$_{2}$-C$_{4 }$ alkenyl group, or R$^{2 }$andR$^{3 }$may bond together to form a ring with the carbon atom to which they are attached; R 4 , Rs and R 6 are each independently a straight, branched or cyclic C$_{1 }$-C$_{12 }$alkyl, alkenyl, oxoalkyl or oxoalkenyl group, C$_{6}$-C$_{20 }$ aryl, C$_{7}$ -C$_{12 }$aralkyl or aryloxoalkyl group, in which at least one hydrogen atom may be substituted by an ether, ester, carbonyl, carbonate, hydroxyl, carboxyl, halogen, cyano, amide, nitro, sultone, sulfonic acid ester, sulfone moiety, or sulfonium salt-containing substituent, R 4 and Rs may bond together to form a ring with the sulfur atom to which they are attached; R$^{7 }$and R$^{8 }$each are a CcC$_{20 }$ aryl group which may contain a straight, branched or cyclic C$_{1 }$-C$_{10 }$alkyl or alkoxy moiety, and m is an integer of 2 to 8. 

15. A process for forming a pattern comprising the steps of applying a resist composition onto a substrate, baking to form a resist film, exposing the resist film to electron beam or extreme ultraviolet radiation of 3 to 15 nm wavelength, and developing the exposed film with a developer, 

wherein the resist composition comprises a base polymer and a sulfonium salt having the general formula (1 )-1 or a iodonium salt having the general formula (1)-2, 

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