Preparations And Optoelectronic Properties Of Pulsed Laser Deposited Oxide Films

Pulsed laser deposition is of great interest due to its numerous merits, for instance,flexibility and precise stoichiometry. As a result, this technique is much suitable forin-situ preparation of solid oxide heterojunction devices. Many oxide materials retainexcellent photoelectronic properties which are promising alternatives ofoptoelectronic devices.In this thesis, we fabricate perovskite manganite, zinc oxide and SrRuO₃thin filmsvia pulsed laser deposition. We deposit polycrystalline and amorphous Ca and Kco-doped manganite on single crystal substrate and ITO substrate, consequently ZnOto form heterojunction, respectively. Both two devices exhibit reproduciblerectifying characteristics and the rectifying ratio is high. We also focus on theoptoelectronic property of heterojunction which is fabricated on ITO substrate withlow deposition temperature under continuous laser irradiation. We measure thecrystalline, morphology, composition property using XRD, AFM, SEM and EDSapproaches. We report here the influence of LCKMO/ZnO bilayers’ thickness on theelectrical and photoelectric properties of the heterostructure at room temperature.The power conversion efficiency （PCE） is achieved when the LCKMO and ZnOlayers are thin enough and the space charge layer is entire. The transport andphotoelectric mechanisms are explored according to the experimental results.Furthermore, we successfully fabricate the ZnO hollow nanospheres monolayerarrays. The ZnO films are deposited on ITO substrate using PLD method andself-assembly polystyrene monolayer template. Later we remove the PS balls byheating. The cross-sectional and surface morphologies of nanospheres of differentthickness are studied via focused ion beam and SEM. We obtain the critical thicknessof the existence of3D hollow spheres. The specific surface area can be enhancedalmost100%by making the crack of the bottom of spheres. Owing to the high surface area and photonic crystal effect, this nanostructure has decent potential inorganic solar cells, hybrid photovoltaics and gas sensors.