Freestanding HfO(2 )grating fabricated by fast atom beam etching

We report here the fabrication of freestanding HfO(2 )grating by combining fast atom beam etching (FAB) of HfO(2 )film with dry etching of silicon substrate. HfO(2 )film is deposited onto silicon substrate by electron beam evaporator. The grating patterns are then defined by electron beam lithography and transferred to HfO(2 )film by FAB etching. The silicon substrate beneath the HfO(2 )grating region is removed to make the HfO(2 )grating suspend in space. Period- and polarization-dependent optical responses of fabricated HfO(2 )gratings are experimentally characterized in the reflectance measurements. The simple process is feasible for fabricating freestanding HfO(2 )grating that is a potential candidate for single layer dielectric reflector. PACS: 73.40.Ty; 42.70.Qs; 81.65.Cf.