Optical characteristics of chemically deposited MnSb2S4 thin films

Abstract

In this research work, manganese antimony sulfide (MnSb2S4) films have been prepared and deposited via the chemical bath deposition route at various thicknesses (189, 275, 329, and 412 nm). The X-ray diffraction results confirmed the polycrystalline character of these films, which exposed orthorhombic structures. The compositional element percentages of these layers were analyzed via energy-dispersive X-ray spectroscopy. The impact of thickness on the optical characteristics of films has also been studied. The optical investigations manifest that these MnSb2S4 films demonstrate a direct optical transition with variable energy gap values (1.77–1.53 eV). The refractive index, optical dielectric constant, absorption coefficient, extinction coefficient, optical conductivity, and others have been estimated and studied. Additionally, the dispersion refractive index, dispersion, and oscillator energies of these spray-deposited films were computed and discussed. In the same way, increasing the thickness of the film has been shown to improve the nonlinear optical parameters. The hot-probe method using a negative voltage was used to investigate the semiconductor behaviour of MnSb2S4 films. It was found that these films tend to behave as p-type semiconductors. This study showed that MnSb2S4 films were utilized as a new absorber layer in photovoltaics.