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Herein R 1 is hydroxyl, C 1 -C 6 alkyl group, C 1 -C 6 alkoxy group, C 2 -C 6 acyloxy group, fluorine, chlorine, bromine, amino group, -NR 1 A----C(=O)-R 1$_{B,}$ or $_{-NR}$1A----C (=O)-O-R 1$_{B,}$ $_{R}$1 A is hydrogen or a C 1 -C 6 alkyl group, RIB is a C 1 -C 6 alkyl, C 2 -C 8 alkenyl, CcC 12 aryl or C 7 -C$_{13 }$ aralkyl group; R 2 is hydrogen, nitro, or a C 1 -C$_{20 }$monovalent hydrocarbon group which may contain at least one moiety selected from hydroxyl, carboxyl, thiol, ether bond, ester bond, nitro, cyano, halogen and amino moiety, in case of p=l, R 2 may bond together to form a ring with the nitrogen atom to which they are attached, the ring optionally con› taining a double bond, oxygen, sulfur or nitrogen, or R 2 and X may bond together to form a ring with the nitrogen atom to which they are attached, the ring optionally containing a double bond, oxygen, sulfur or nitrogen; X is a C 1 -C$_{20 }$ divalent hydrocarbon group which may contain at least moiety selected from ester bond and ether bond; m and n are independently an integer meeting lsms5, 0sns4 and Ism+ ns5, and pis 1, 2 or 3. 

[0019] The resist composition may further comprise an acid generator capable of generating a sulfonic acid, imide acid or methide acid. 

[0020] The resist composition may further comprise an organic solvent. 

[0021] In a preferred embodiment, the base polymer com› prises recurring units having the formula (al) or recurring units having the formula (a2). 

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Herein RA is each independently hydrogen or methyl, R 11 and R 12 each are an acid labile group, Y 1 is a single bond, phenylene group, naphthylene group, or C 1 -C 12 linking group containing at least one moiety selected from ester bond and lactone ring, and Y 2 is a single bond or ester bond. 

[0022] Typically, the resist composition is a chemically amplified positive resist composition. 

[0023] In another embodiment, the base polymer is free of an acid labile group. 

[0024] Also typically, the resist composition is a chemi› cally amplified negative resist composition. 

[0025] In a preferred embodiment, the base polymer fur› ther comprises recurring units of at least one type selected from recurring units having the formulae (fl) to (f3). 

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[0026] Herein RA is each independently hydrogen or methyl. Z 1 is a single bond, phenylene group, or ----C(=O)-NH-Z 11 -, Z 11 is a Cl-C6 alkanediyl group, C 2 -C 6 alkenediyl group, or phenylene group, which may contain a carbonyl, ester bond, ether bond or hydroxyl moiety. Z 2 is a single bond, -Z 21 -C(=O)-O-, -Z 21 - O- or -Z 21 ---0-C(=O)-, Z 21 is a cl -C12 alkanediyl group which may contain a carbonyl moiety, ester bond or ether bond. Z 3 is a single bond, methylene, ethylene, phe› nylene, fluorinated phenylene, ---O-Z 31 -, ----C(=O)› O-Z31-, or ----C(=O)-NH-Z 31 -, Z 31 is a C 1 -C 6 alkanediyl group, C 2 -C 6 alkenediyl group, phenylene group, fluorinated phenylene group, or trifluoromethyl-substituted phenylene group, which may contain a carbonyl moiety, ester bond, ether bond or hydroxy moiety. R 21 to R 28 are each independently a C 1 -C$_{20 }$ monovalent hydrocarbon group which may contain a heteroatom, any two ofR 23 , R 24 and R 25 or any two of R 26 , R 27 and R 28 may bond together to form a ring with the sulfur atom to which they are attached, A is hydrogen or trifluoromethyl, and M- is a non-nucleophilic counter ion. 

[0027] The resist composition may further comprise a surfactant. 

[0028] The resist composition may further comprise a quencher other than the amine compound. 

[0029] In another aspect, the invention provides a process for forming a pattern comprising the steps of applying the resist composition defined herein onto a substrate, baking to form a resist film, exposing the resist film to high-energy radiation, and developing the exposed resist film in a devel› oper. 

[0030] Typically, the high-energy radiation is ArF excimer laser radiation of wavelength 193 nm, KrF excimer laser radiation of wavelength 248 nm, EB, or EUV of wavelength 3 to 15 nm. 

