Source: unknown

Herein m is an integer of 1 to 5, n is an integer of 0 to 4, 1≤m+n≤5, p^1 is 1, 2 or 3, p^2 is 1 or 2, q^1 is 1, 2 or 3, and q^2 is 1, 2 or 3. X^1 is a C_1-C_20 (p^1+1)-valent hydrocarbon group which may contain at least one moiety selected from ester bond and ether bond. R^1 is hydroxyl, C_1-C_6 saturated hydrocarbyl group, C_1-C_6 saturated hydrocarbyloxy group, C_2-C_6 saturated hydrocarbylcarbonyl group, fluorine, chlorine, bromine, amino group, —NR^{14}—C(=O)—R^{16}, or —NR^{14}—C(=O)—R^{17}, wherein R^{14} is hydrogen or a C_1-C_6 saturated hydrocarbyl group, R^{16} is a C_1-C_6 saturated hydrocarbyl, C_2-C_6 unsaturated aliphatic hydrocarbyl, C_6-C_12 aryl or C_7-C_12 aralkyl group. R^{17} is hydrogen, nitro, or a C_1-C_20 hydrocarbyl group which may contain at least one moiety selected from hydroxyl, carbonyl, thiol, ether bond, ester bond, nitro, cyano, halogen and amino moiety, in case of p^1=1 or 2, two R^{2} 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, or R^{2} and X^1 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^{87} is iodine or bromine. X^2 is a single bond, ether bond, ester bond, amide bond, carbonyl group or carbonate group. X^3 is a single bond or a C_1-C_20 (q^1+1)-valent hydrocarbon group which may contain a heteroatom exclusive of iodine and bromine. R^3 is a C_1-C_20 (q^1+1)-valent aliphatic hydrocarbon group which may contain at least one moiety selected from fluorine, chlorine, hydroxyl, carbonyl, C_6-C_12 aryl, ether bond, ester bond, carbonyl, amide bond, carbonate, urethane bond, and urea bond.

[0020] The resist composition may further comprise an acid generator capable of generating a sulfonic acid, imide acid or methide acid and/or an organic solvent.

[0021] In a preferred embodiment, the base polymer comprises recurring units having the formula (a1) or recurring units having the formula (a2).

Herein R^4 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] In one embodiment, the resist composition is a chemically amplified positive resist composition.
[0023] In another embodiment, the base polymer is free of an acid labile group. The resist composition is typically a chemically amplified negative resist composition.
[0024] The base polymer may comprise recurring units of at least one type selected from recurring units having the formulae (f1) to (f3).

Herein R^4 is each independently hydrogen or methyl. Z^1 is a single bond, phenylene group, —O—Z^{11}—, —C(=O)—O—Z^{11}— or —C(=O)—NH—Z^{11}—, wherein Z^{11} is a C_1-C_6 aliphatic hydrocarbylene group or phenylene group, which may contain carbonyl, ester bond, ether bond or hydroxyl moiety. Z^2 is a single bond, —Z^{23}—C(=O)—O—, —Z^{23}—O— or —Z^{23}—O—C(=O)—, wherein Z^{23} is a C_1-C_{12} saturated hydrocarbylene group which may contain