Carboxylate salt, photoresist composition including the same, and method of forming pattern by using the photoresist composition

A carboxylate salt represented by Formula 1:

• wherein, in Formula 1,
• A11 is a cyclic C1-C20 hydrocarbon group that selectively includes a heteroatom, and represents at least one of a carbon-carbon single linkage or a carbon-carbon double linkage,
• R11 to R15 are each independently at least one of hydrogen;
• deuterium;
• a halogen;
• or a linear, branched, or cyclic C1-C20 monovalent hydrocarbon group that optionally includes a heteroatom,
• b15 is an integer from 0 to 10,
• n11 and n12 are each 0, 1, or 2 such that the sum of n11 and n12 is 1 or 2, and
• M+ is a at least one of a substituted or unsubstituted sulfonium cation, a substituted or unsubstituted iodonium cation, or a substituted or unsubstituted ammonium cation.