Spontaneously generated sinusoidallike structures on Ti-Ni thin film under focused ion-beam bombardment

A new fabrication method for a sinusoidallike structure is described. The sinusoidal structure can be spontaneously self-formed on the surface of a substrate by focused ion-beam bombardment with raster scanning and an ion incident angle perpendicular to the sample surface (normal incidence). The substrate material is a silicon wafer coated with 2-mum-thick Ti-Ni thin film. We show by measurement and analysis of the grating characteristics at the working wavelength range from 50 to 1500 nm that the technique of self-organized formation is a valid approach for microfabrication of diffractive structures, and the spontaneously generated structure under ion bombardment is applicable for a sinusoidal grating that functions from the ultraviolet to the near-infrared wavelength range.