High sensitive SiO2/TiO2 hybrid sol-gel material for fabrication of 3 dimensional continuous surface relief diffractive optical elements by electron-beam lithography.

A negative-tone sensitive SiO2/TiO2 organic-inorganic hybrid sol-gel material was synthesized and characterized for fabrication of multilevel micro-optical elements by direct electron-beam lithography. The exposure was carried out by an in-house modified electron-beam writing system using LEO SEM-982 with Elphy Quantum exposure beam-blanking control system at 25keV. The hybrid Sol-Gel material demonstrated a superb sensitivity for doses between 0.22microC/cm2 and 0.33microC/cm2.