Preparation and quality assessment of CuS thin films encapsulated in glass

Copper sulfide (CuS)-based thin films with different thickness have been prepared by thermal co-evaporation of the elemental constituents. Morphological and microstructural properties were shown to vary with film thickness. Optical properties of films encapsulated in a double-glazed configuration and containing an air gap have been measured. Encapsulated CuS films of thickness 100 and 150 nm showed high transmittance peak values of 48% and 36%, respectively, and a low reflectance below 20% and 15%, respectively, in the visible region. A low transmittance of ~ 10% (~ 15%) and a high reflectance of ~ 45% (~ 40%) in the near-infrared region were obtained for the film with 150 nm (100 nm). Thermal stability of the films has been proved by annealing of the films in air and Argon at 150 °C.