Simple Method for Fabrication of Light Diffraction Gratings from Ultraviolet to Infrared

Periodical structures with a wave-like shape were fabricated on semiconductors surfaces by utilizing ion milling from a Liquid Metal Ion Gun (LMIG) of bismuth. The symmetrical structures exhibit a well-defined shape and uniformity all over the irradiated area. Wavelength and amplitude of the ripples can be modified by varying the number of pixels and ion fluence, respectively. It was found that the ripples have potential applications as diffraction gratings for visible light. Furthermore, is possible to modify the wavelength of the gratings for applications in the range of infrared and ultra violet, this can be done by selecting the appropriate ion beam diameter. In this work, several gratings were fabricated on Si, Ge and ZnSe surfaces with a wavelength ranging from 294 nanometers up to 4.7 micrometers. A simple and accurate method for fabrication of light diffraction gratings is suggested.