Photosensitive polymer, photoresist composition including the same, and method of manufacturing semiconductor device

A photoresist composition comprising:

• a photoacid generator (PAG);
• a solvent;
• and
• a photosensitive polymer including repeating units that are represented by Formula 1,
• wherein, in Formula 1, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently a hydrogen atom, a C1-C3 linear or branched alkyl group, a substituted or unsubstituted C2-C3 linear or branched alkenyl group, a substituted or unsubstituted C2-C3 linear or branched alkynyl group, a substituted or unsubstituted C1-C3 alkoxy group, or a halogen element,
• A is an acid-labile group having an acid desorption rate that is lower than a acid desorption rate of a trialkylsilyl group.

A method of manufacturing a semiconductor device, the method comprising:

• forming a photoresist film on a feature layer using a photoresist composition, a photoacid generator (PAG), and a solvent;
• exposing a first region to light, the first region being a portion of the photoresist film, the exposing the first region to light forming an exposed region of the photoresist film and a non-exposed region of the photoresist film;
• forming a photoresist pattern by removing the exposed region of the photoresist film using a developer;
• and
• processing the feature layer by using the photoresist pattern, wherein
• the photosensitive polymer has a polydispersity index (PDI) of 1.1 or less,
• the photoresist composition includes a photosensitive polymer with repeating units represented by Formula 1 and obtained by anionic polymerization of a p-hydroxystyrene monomer and a p-styrene monomer, the p-hydroxystyrene monomer having a hydrogen atom of a hydroxyl group substituted with a trialkylsilyl group and the p-styrene monomer having a hydrogen atom substituted with an acid-labile functional group,
• wherein, in Formula 1,
• R1, R2, R3, R4, R5, R6, R7, and R8 are each independently a hydrogen atom, a C1-C3 linear or branched alkyl group, a substituted or unsubstituted C2-C3 linear or branched alkenyl group, a substituted or unsubstituted C2-C3 linear or branched alkynyl group, a substituted or unsubstituted C1-C3 alkoxy group, or a halogen element,
• A is an acid-labile group having an acid desorption rate which is lower than that of a trialkylsilyl group, and
• m and n are each an integer of 1 or more.