Patent ID: 7160665

Claim:
A lithographic method comprising: providing a bilayer film on a surface of a substrate to be patterned comprising one of a semiconductor material, a conductive material or an insulating material, wherein said bilayer film comprises an underlayer located on said surface of said substrate and an overlaying layer on a surface of said underlayer, wherein said underlayer is unpatterned and comprises (i) a photoacid generator and (ii) a polymeric material that includes at least one of an organic polymer and an inorganic matrix material, and wherein the overlying layer comprises a polymer resin that has reactive acid labile functionality and is substantially free of a photoacid generator; simultaneously irradiating the overlaying layer and the underlayer to generate acid throughout a patterned region in the underlayer; and transferring the pattern formed in the underlayer to said overlaying layer, said transferring comprising vertically transporting acid from the underlayer to the overlaying layer by diffusion to substantially enhance the density of acid throughout the overlaying layer, wherein sufficient acid is present in the overlaying layer to permit lithographic patterning of the overlaying layer, and the photoacid generator is selected to enhance said vertically transporting.