Resist composition and patterning process

A resist composition comprising a quencher containing a sulfonium salt having the formula (1):

• wherein R1 and R2 are each independently a single bond or a C1-C20 divalent aliphatic hydrocarbon group which may contain an ether bond, ester bond or hydroxyl,
• L1 is an ester bond, ether bond or amide bond,
• L2 and L3 are each independently a single bond, ester bond, ether bond or amide bond,
• R3 is hydroxyl, carboxyl, nitro, cyano, fluorine, chlorine, bromine, amino, or a C1-C20 alkyl, C1-C20 alkoxy, C2-C20 acyloxy, C2-C20 alkoxycarbonyl or C1-C4 alkylsulfonyloxy group, which may contain fluorine, chlorine, bromine, hydroxyl or amino, or —NR3A—C(═O)—R3B or —NR3A—C(═O)—O—R3B, wherein R3A is hydrogen or a C1-C6 alkyl group which may contain halogen, hydroxyl, C1-C10 alkoxy, C2-C10 acyl or C2-C10 acyloxy, R3B is a C1-C16 alkyl, C2-C16 alkenyl or C6-C12 aryl group, which may contain halogen, hydroxyl, C1-C10 alkoxy, C2-C10 acyl or C2-C10 acyloxy,
• R4 is hydroxyl, carboxyl, nitro, cyano, fluorine, chlorine, bromine, iodine, amino, or a C1-C20 alkyl, C1-C20 alkoxy, C2-C20 acyloxy, C2-C20 alkoxycarbonyl or C1-C4 alkylsulfonyloxy group, which may contain fluorine, chlorine, bromine, iodine, hydroxyl, amino or ether bond,
• R5 is a C1-C20 monovalent hydrocarbon group which may contain a heteroatom, in case of r=1, two R5 may be the same or different and may bond together to form a ring with the sulfur atom to which they are attached,
• X− is a carboxylic acid anion, amic acid anion, fluorine-free sulfonic acid anion or halide ion,
• m is an integer of 1 to 5, n is an integer of 0 to 3, the sum of m+n is 1 to 5, p is 0 or 1, q is an integer of 0 to 4, and r is an integer of 1 to 3.