Patent ID: 11914291
Assignee: SHIN-ETSU CHEMICAL CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 7:
8. The resist composition of claim 3 wherein the base polymer comprises recurring units of at least one type selected from the formulae (f1) to (f3):, wherein RA is each independently hydrogen or methyl,
Z1 is a single bond, phenylene group, —O—Z11—, —C(═O)—O—Z11— or —C(═O)—NH—Z11—, Z11 is a C1-C6 aliphatic hydrocarbylene group or phenylene group, which may contain carbonyl, ester bond, ether bond or hydroxyl,
Z2 is a single bond, —Z21—C(═O)—O—, —Z21—O— or —Z21—O—C(═O)—, Z21 is a C1-C12 saturated hydrocarbylene group which may contain carbonyl, ester bond or ether bond,
Z3 is a single bond, methylene, ethylene, phenylene, fluorinated phenylene, —O—Z31—, —C(═O)—O—Z31— or —C(═O)—NH—Z31—, Z31 is a C1-C6 aliphatic hydrocarbylene group, phenylene group, fluorinated phenylene group, or trifluoromethyl-substituted phenylene group, which may contain carbonyl, ester bond, ether bond or hydroxyl,
R21 to R28 are each independently a C1-C20 hydrocarbyl group which may contain a heteroatom, any two of R23, R24 and R25 or any two of R26, R27 and R28 may bond together to form a ring with the sulfur atom to which they are attached,
A1 is hydrogen or trifluoromethyl, and
M− is a non-nucleophilic counter ion.