Polymer, resist composition comprising the same and method of forming pattern using the same

A polymer comprising:

• a first repeating unit represented by Formula 1 below;
• and
• a second repeating unit represented by Formula 2 below,
• wherein, in Formulae 1 and 2,
• L11 to L13 and L21 to L24 are each independently:
• a single bond;
• O;
• S;
• C(═O);
• C(═O)O;
• OC(═O);
• C(═O)NH;
• NHC(═O);
• S(═O);
• S(═O)2O;
• OS(═O)2;
• or a linear, branched, or cyclic C1-C30 divalent hydrocarbon group optionally including a heteroatom,
• a11 to a13 and a21 to a24 are each independently an integer from 1 to 4,
• A11 and A21 are each independently a C6-C30 aryl group or a C1-C30 heteroaryl group,
• X11 is a photo-degradable group,
• R11 is a halogen atom, or a linear, branched, or cyclic C1-C30 monovalent hydrocarbon group optionally including a heteroatom,
• R21 is a halogen atom, or a linear, branched, or cyclic C1-C30 monovalent hydrocarbon group substituted with a halogen atom,
• R12 and R22 are each independently:
• hydrogen;
• deuterium;
• a halogen atom;
• a cyano group;
• a hydroxyl group;
• an amino group;
• a carboxylate group;
• a thiol group;
• a carbonyl moiety;
• an ester moiety;
• a sulfonate moiety;
• a carbonate moiety;
• a lactone moiety;
• a sultone moiety;
• a carboxylic anhydride moiety;
• or a linear, branched, or cyclic C1-C30 monovalent hydrocarbon group optionally including a heteroatom,
• R23 is:
• hydrogen;
• deuterium;
• a halogen atom;
• a cyano group;
• a hydroxyl group;
• an amino group;
• a carboxylate group;
• a thiol group;
• a carbonyl moiety;
• an ester moiety;
• a sulfonate moiety;
• a carbonate moiety;
• a lactone moiety;
• a sultone moiety;
• a carboxylic anhydride moiety;
• a linear, branched, or cyclic C1-C30 monovalent hydrocarbon group optionally including a heteroatom;
• or a photo-degradable group,
• b12, b22, and b23 are each independently an integer from 1 to 10,
• p11 is an integer from 1 to 3,
• p21 is an integer from 0 to 4, and
• * is a binding site with an adjacent atom.