Optical properties of thermally vacuum evaporated thin films

摘要: Silver antimony diselenide thin films were prepared by a thermal vacuum evaporation technique onto quartz and glass substrates kept at room temperature . The as-deposited amorphous transformed to face centred cubic (FCC) polycrystalline nature with the lattice constant on post-deposition annealing above 423 K for one hour in argon atmosphere. optical constants (the refractive index n, absorption k) of determined several samples different thickness (180 nm-270 nm), using spectrophotometric measurements transmittance T reflectance R normal incidence spectral range 500-2500 nm. These also preannealed films, (polycrystalline). obtained values both n k independent film within above-mentioned range. data fitted single-oscillator model high-frequency dielectric increasing from 13 15 crystalline films. It was found that has same as analysis behaviour coefficient intrinsic region revealed existence an indirect allowed transition energy gap 1.2 eV 1.03 respectively.