Proliferation in the photo-response characteristics of MDC thin films for optoelectronic applications through NSP technique

Abstract

Nebulizer spray pyrolysis (NSP), a simple thin-film deposition method, was used to fabricate p-Si/n-manganese-doped cerium oxide (MDC)/Al photodiodes. The structure, morphology, optics, composition, electrical and rectifying properties of the prepared materials were analyzed. UV-Vis analysis demonstrates a prominent and acute absorption edge at 425 nm in the visible region. As more Mn impurities are incorporated into CeO2 crystallites, the band gap decreases as the doping level increases, leading to the formation of new recombination sites with low energy emissions. Electrons in outer orbits operate in energy bands, moving to higher energy levels. At higher Mn doping, some NBE emissions and green emission peaks disappear. The emission spectrum confirmed that strong and broad blue emission peak occurred for the diode containing the 15% Manganese Diode Cerium film. XRD peak shows the mono-phase polycrystalline cubic fluorite structure with the main orientation in the 200 directions. The broad lines (CeO) symmetry at 695,659,538 and 517 cm−1 observed in the Fourier Transform -Infrared spectrum are due to the phonons of the cerium oxide (Ce-O) network caused by asymmetric tip stretching and fastening vibration. Satellite peaks arise due to the transition from ligand (O 2p) to metal (Ce 4f) achieved during the primary and main photo-ionization process. This suggests that the valence states of Ce3+ and Ce4+ provide access to the CeO2 lattice sites. The I-V properties of p-Si/n-MDC/Al devices show behavior limited by the properties of the inorganic semiconductor substrate and the size of the hetero-interface energy barrier. The switching voltage of the hetero-junction was found to be approximately 2.4 V.