The radiation-sensitive resin composition and pattern forming method

An object of the present invention has excellent basic properties as a resist, is to provide a radiation sensitive resin composition excellent in circularity and CD Uniformity at the time of forming the contact hole pattern. This radiation sensitive resin composition, the acid-dissociable group-containing resin which becomes alkali-soluble (A) by the action of an acid, acid generator (B), and the solvent (C) and radiation-sensitive resin composition containing a is, the resin (a) are those comprising the repeating unit represented by the following general formula (1) and (2). [R ]