Sputtered Nanocrystalline Nickel Thin Films for Solar Thermal Energy Applications

Optical properties of sputtered nickel thin films and nanocrystalline materials are important in solar thermal energy applications. Optical constants of sputtered nickel thin films were analyzed in this work using spectroscopic infrared ellipsometry in the wavelength region from 1.5 μm to 30 μm as a function of film thickness. Surface roughness, nanocrystal size, and crystal orientation of the nickel thin films were also analyzed to correlate with the optical properties. Increasing film thickness, optical constant n decreases and optical constant k increases in this infrared region. This experimental work provided a wide wavelength range of infrared optical constants of the sputtered nickel thin films by correlating them with other physical properties of the thin films.