Patent ID: 7632623

Claim:
A positive resist composition comprising: a resin which increases solubility in an alkali developing solution by an action of an acid and comprises a repeating unit containing a lactone structure and a cyano group, a repeating unit containing a first group selected from groups represented by the following formulae (pI) to (pV) and a repeating unit containing a second group selected from groups represented by the following formulae (pI) to (pV) which is different from the first group; a compound which generates an acid upon irradiation of an actinic ray or a radiation; and a solvent: wherein R 11 represents an alkyl group or a cycloalkyl group, Z represents an atomic group necessary for forming a cycloalkyl group together with the carbon atom, R 12 to R 16 each independently represents an alkyl group or a cycloalkyl group, provided that at least one of R 12 to R 14 or either R 15 or R 16 represents a cycloalkyl group, R 17 to R 21 each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group, provided that at least one of R 17 to R 21 represents a cycloalkyl group and either R 19 or R 21 represents an alkyl group or a cycloalkyl group, and R 22 to R 25 each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group, provided that at least one of R 22 to R 25 represents a cycloalkyl group, alternatively, R 23 and R 24 may be combined with each other to form a ring.