Some Optical Properties of Manganese Sulfide (MnS) Thin-films

Abstract

The aim of this study is to investigate the effects of thermal treatment and the Laser of MnS thin films, and their optical properties. In this work, thin-films of Manganese Sulfide (MnS) were prepared by thermal evaporation, on glass substrate which has thickness of 1mm, and refractive index 1.52 under high vacuum of 2×10-7 torr. The Differential Thermal Analysis (DTA) for MnS in powder form revealed that melting point is 700Co. The effects of thermal treatment beside the transmission of Laser beam on MnS were investigated. The thickness of film is determined by using laser interference phenomenon, the value of thickness is found to be 0.085 μm. The transmission property is found by utilizing ultraviolet visible spectrophotometer. After heat treatment is found that the light transmission is temperature dependent in the visible and ultraviolet-visible region. The transmission increases with temperature, while absorption decreases upon increasing the Laser wavelength. At high temperatures the layer showed thermal instability, due to changing in the thickness which decreases as temperature increases. The optical properties, like absorption coefficient, transmission and refractive index were calculated for each sample at different temperatures. The results showed the possibility of utilizing these films as filters in wave lengths 307nm to 577nm.