Interferometric lithography for nanoscale fabrication

Interferometric lithography (IL) techniques provide a demonstrated, low-cost, large area nanoscale patterning capability with feature resolution to similar to 50 nm. Combining IL,with anisotropic etching (both by reactive-ion etching and by KOH wet etching) and with 3-D oxidation techniques provides a suite of techniques that accesses a broad range of Si nanostructures (as small as 10 nm) over large areas and with good uniformity. Optical characterization includes measurements of reflectivity for a wide range of 1D grating profiles, and Raman scattering characterization of Si nanostructures. Three regimes are found for the Raman scattering: bulk (10 linewidths of similar to 200 nm), resonant enhanced (similar to 50 nm linewidths) and asymmetry and splitting (linewidths < 20 nm).