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

Abstract

The present invention addresses the problem of providing a strontium salt used in a chemical amplification inhibitor composition that exhibits excellent solvent solubility, high sensitivity and high contrast, and excellent photolithography performance such as LWR, CDU, MEF, EL, and DOF in photolithography using high-energy rays; a chemical amplification inhibitor composition containing the strontium salt as a photoacid generator; and a patterning method using the chemical amplification inhibitor composition. The solution to this problem is a strontium salt, represented by the following formula (1). In this formula, Z- is a fluoroalkyl sulfonic acid anion without a polymerizable group. A sulfonium salt has the following formula (1): wherein Z- is a fluoroalkanesulfonic acid anion free of polymerizable group.