Fabrication of high-spatial-frequency gratings through computer-generated near-field holography

We demonstrate an innovative method for fabrication of high-spatial-frequency grating structures. This technique makes use of the near-field diffraction patterns from computer-generated phase holograms for lithographic fabrication of grating structures with periods that are one half that of the phase hologram mask. Linear, rectilinear, and circular gratings were fabricated with this technique. Experimental results from gratings with periods to $0.5 \mu \mathrm{m}$ and feature sizes to $\sim 0.2 \mu \mathrm{m}$ are presented.