Electrical Characterization of ZnO (Al) / p-Si Heterojunctions Fabricated by SolGel Method

In this work, the electrical properties of heterojunctions formed by coating of undoped Zinc Oxide (ZnO) and 2% Aluminum doped zinc oxid (AZO) on p-type silicon (p-Si) were investigated. ZnO and AZO nanoparticles were synthesized by Sol-Gel method and ZnO / p-Si, ZnO (Al) / p-Si heterojunctions were formed by spin coating technique. After the coating, the samples were thermally annealed at 450 oC for 30 minutes. Current-Voltage (I-V) and Capacitance-Voltage (C-V) measurements taken at 10K-300K show that the samples exhibit diode behavior with very low leakage current. Built-in potential (Vbi) and carrier concentrations (Nd) of diodes were calculated from C-V measurement results. Deep level transition spectroscopy (DLTS) technique was used to investigate trap levels around the depletion region. The presence of electron traps in both samples was determined