Organic salt, resist composition including the same, and pattern formation method using the resist composition

An organic salt represented by Formula 1:

• wherein, in Formula 1,
• A11 is a linear or cyclic C1-C30 hydrocarbon group optionally including a heteroatom,
• k11 is selected from integers of 1 to 4,
• L11 and L12 are each independently:
• a single bond;
• O;
• S;
• C(═O);
• C(═O)O;
• OC(═O);
• C(═O)NR12;
• NR12C(═O);
• S(═O);
• S(═O)2;
• S(═O)2O;
• OS(═O)2;
• or a linear, branched or cyclic C1-C30 divalent hydrocarbon group optionally including a heteroatom,
• a11 and a12 are each independently selected from integers of 0 to 4,
• R11 and R12 are each independently hydrogen, deuterium, a halogen atom, a cyano group, a hydroxyl group, or a linear, branched or cyclic C1-C20 monovalent hydrocarbon group optionally including a heteroatom,
• b11 is selected from integers of 0 to 10,
• any two adjacent groups among R11, L11 and L12 are optionally bonded to each other to form a ring,
• any two adjacent groups among a plurality of R11 groups are optionally bonded to each other to form a ring,
• n11 is selected from integers of 1 to 5, and
• M+ is a counter cation.