Patent ID: 7244549

Claim:
A pattern forming method comprising steps of: providing a film containing a polymer with a carbon content of 80 wt % or more and a polystyrene-reduced weight average molecular weight of 500–100,000, providing a radiation-sensitive resin composition containing an acid-dissociable group-containing polysiloxane which is alkali-insoluble or scarcely alkali-soluble but becomes alkali-soluble when the acid-dissociable group dissociates, forming a coating of the radiation-sensitive resin composition on the film, and applying radiation to the coating; wherein the acid-dissociable group-containing polysiloxane contains a structural unit of the following formula (2) and a structural unit of the following formula (3), wherein A 1 and A 2 individually represent a monovalent organic group having an acid-dissociable group which dissociates by the action of an acid and R 4 represents a linear, branched, or cyclic alkyl group having 1–10 carbon atoms or a linear, branched, or cyclic halogenated alkyl group having 1–10 carbon atoms; and wherein the acid-dissociable group represented by A 1 in the formula (2) is a group of the following formula (10), —P-Q-R 8 (10) wherein P indicates a single bond, a methylene group, a difluoromethylene group, a substituted or unsubstituted, linear or branched alkylene group having 2–20 carbon atoms, or a substituted or unsubstituted, divalent alicyclic group having 3–20 carbon atoms, Q represents a —COO— or —O— group, and R 8 represents a monovalent organic group dissociable by the action of an acid to produce hydrogen atoms.