Patent ID: 8637229

Claim:
A pattern forming method, comprising: applying, to a substrate, a resist composition of which solubility in a positive developer which is an alkali developer increases and solubility in a negative developer containing an organic solvent decreases upon irradiation with actinic rays or radiation, so as to form a resist film; exposing the resist film; and developing the resist film with the negative developer, wherein the negative developer containing an organic solvent is a developer consisting of butyl acetate, and the resist composition contains a resin having a monocyclic or polycyclic alicyclic hydrocarbon structure and contains a repeating unit represented by the following formula (pA): wherein R represents a hydrogen atom, a halogen atom or a linear or branched alkyl group having a carbon number of 1 to 4, and a plurality of R's may be the same or different; A represents a single bond, or a sole group or a combination of two or more groups selected from the group consisting of an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amido group, a sulfonamido group, a urethane group and a ureylene group; and Rp 1 represents a group represented by any one of the following formulae (pI) to (pV); in formulae (pI) to (pV), R 11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl 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 a linear or branched alkyl group having a carbon number of 1 to 4 or a cycloalkyl group, provided that at least one of R 12 to R 14 or either one of R 15 and R 16 represents a cycloalkyl group; R 17 to R 21 each independently represents a hydrogen atom, a linear or branched alkyl group having a carbon number of 1 to 4 or a cycloalkyl group, provided that at least one of R 17 to R 21 represents a cycloalkyl group and that either one of R 19 and R 21 represents a linear or branched alkyl group having a carbon number of 1 to 4 or a cycloalkyl group; R 22 to R 25 each independently represents a hydrogen atom, a linear or branched alkyl group having a carbon number of 1 to 4 or a cycloalkyl group, provided that at least one of R 22 to R 25 represents a cycloalkyl group; and R 23 and R 24 may combine with each other to form a ring.