Synthesis and characterization of some binary chalcogen compounds by explosive laser irradiation and heat treatment

The thin film preparation of Se, Ge, Sn monolayers and also binary chalcogenide alloys with their various structures and morphologies have been thoroughly studied. A new phase of the composite materials was identified. The short range ordering structure of chalcogens when mixed up with four-fold-coordinated atoms like Ge and Sn produce alloys or compounds with a certain specific characteristic. Laser impulse on these materials caused rapid cooling allowing the materials to form alloys. The optical measurements of the chalcogen films are reported. The transmittance versus wavelength measurement in the UV-VIS-NIR was studied and the optical band gaps of the films were calculated to be 1.48 eV for Ge-Se and 1.65 eV for Sn-Se for the wavelength range 300-1100 nm.