Patent ID: 7758794

Claim:
A method of making an article comprising a nanoscale surface pattern having reduced edge and/or sidewall roughness comprising the steps of: providing a mold with a molding surface having one or more nanoscale protruding regions tapering toward the end distal the surface, the protruding regions arranged complementary to the pattern, at least one of the protruding features having a minimum lateral dimension less than 200 nanometers and smooth edges and sidewalls having a minimum surface roughness of less than 5 nanometers; providing a workpiece comprising a substrate and a moldable surface layer; pressing together the molding surface and the moldable surface to reduce the thickness of the moldable surface layer under the protruding features; and separating the mold from the moldable surface; wherein providing the mold comprises providing a mold substrate having a nanoscale pattern of etch resistant masking material; anisotropically etching portions of the masked mold substrate to etch recessed regions with converging walls, thereby leaving tapered protruding regions under the masking material; removing the masking material; depositing a second etch resistant material on portions of the tapered protruding regions by to form masked protruding regions; and etching the masked protruding regions to produce substantially vertical sidewalls on the unmasked portions of the protruding regions.