| abstract |
[PROBLEMS] To provide a polymer suitable as a base resin of a positive resist material having a high resolution and a small line edge roughness, which is higher than that of a conventional positive resist material, a positive resist material containing the same, and a pattern forming method using the same. A polymer comprising a repeating unit represented by the following formula (a), a repeating unit represented by the following formula (b) and a repeating unit represented by the following formula (c) and having a weight average molecular weight of 1,000 to 500,000 . Wherein R 1 is a halogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, or an acetoxy group, R 2 is an acid labile group R 3 and R 4 are each independently a halogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, and p is 0 or 1. q and r are each independently an integer of 0 to 4 .) |