Morphological, optical and electrical properties of GaSe9 films and its application in photovoltaic devices

摘要: We report on the characterization of crystalline GaSe9 thin films produced by thermal evaporation onto fluorine doped tin oxide (FTO) transparent electrode substrate, and its further application in photovoltaic devices. The physical properties are studied order to understand implications gallium addition Se alloy. Hexagonal structure after annealing is confirmed X-ray diffraction, whereas scanning electron microscopy images indicate improved morphology films, comparison films. Photoelectrical devices current density–voltage, capacitance–voltage impedance spectroscopy measurements. based show average power conversion efficiency 1.37 %, under 100 mW/cm2 AM 1.5 irradiance, a simple FTO/GaSe9/Au structure. It means an increase 40 % with respect same Additional improvements related built-in potential, charge carrier concentration depletion width, which derived Schottky–Mott relationship. Finally, from measurements, recombination time faster extraction GaSe9-based observed.