Sulfonium salt monomer, polymer, chemically amplified resist composition, and pattern forming method

Abstract

The present invention addresses the need for providing a strontium salt monomer, a polymer containing repeating units from the strontium salt monomer, a chemical amplification inhibitor composition containing the polymer, and a patterning method using the chemical amplification inhibitor composition that exhibits excellent solvent solubility, high sensitivity, high contrast, and superior lithography performance such as LWR, CDU, EL, and DOF in photolithography using high-energy rays. The solution to this problem is a strontium salt monomer, represented by the following formula (A). In this formula, Z- represents a fluoroalkyl sulfonic acid anion with a polymerizable group. A sulfonium salt monomer having the following formula (A): wherein Z- is a fluoroalkanesulfonic acid anion having a polymerizable group.