US Patent 7745094 Resist composition and patterning process using the same

A resist composition is provided comprising a silicone resin, a photoacid generator, a nitrogen-containing organic compound, and a solvent. The silicone resin is obtained through cohydrolytic condensation of a mixture of three silane monomers containing a fluorinated norbornane group, an organic group having a carboxyl group protected with an acid labile group, and a lactone ring-bearing organic group, respectively. The resist composition has satisfactory resolution and overcomes the problem of a low selective etching ratio between resist film and organic film during oxygen reactive etching.