| This paper introduces the use of surface plasmon resonance, transparent dielectric microspheres and laser irradiation to improve the photoelectric properties of ZnO materials.First of all, laser pulse deposition technology was used to grown ZnO thin films with a variety of substrates(sapphire, SiC, ZnO single crystal, Ti, graphene). Detection methods, such as XRD, Raman spectra show that the optimal growth temperature of Ti-ZnO thin film is 500 oC. ZnO-graphene thin film has good fluorescence properties. First principles calculation results show that zinc atom first combined with the C atom in graphene during the ZnO molecules adsorbed on the surface of graphene. The outermost electron of zinc atom transfered to the graphene surface, and formed a strong chemical bonds.Secondly, we have shown the enhanced UV emission and decreased visible emission of Au/ZnO/sapphire and ZnO/Au/sapphire films. AFM results show that the size of Au nanoparticles is 20 nm in Au/ZnO. And SEM results show that the Au is 80 nm in ZnO/Au. By the means of electromagnetic simulation, the electric field intensity spatial distributions over the ZnO film(in the xz plane) and ZnO surface(in the xy plane) have been investigated. The electric field intensity in ZnO film and ZnO surface has been enhanced. The simulation of EED shows the same trend of the change of electric field intensity. Simulation results show that the value of D can significantly affect the electric field intensity distribution of the incident light. Since the PL intensity can be adjusted by electric field intensity. It indicates that the enhancement of UV intensity is a result of the enhanced electric field intensity of the 325 nm stimulate light which induced by localized surface plasmons resonance LSPR. Due to the localized surface plasmon resonance LSPR, the electric field intensity of incident light which radiate into the ZnO film is enhanced. The enhanced electric field intensity will increase the radiative recombination of electron at the conduction band and hole at the valence band. On the other hand, electron transfer which induced by the local surface may be can also affect the enhancements of UV emissions. From the PL results of ZnO/Au/sapphire films, we think that surface passivation is not the main reason for the decline of the visible emission. The suppression of the visible emissions might be due to flowing of the electrons from defects states to Au Fermi level, which caused the reduction of the electrons in the defect states.Then, a strong enhancement in ultraviolet photoluminescence(UV-PL) of ZnO thin films(grown on a SiC substrate) has been achived by monolayer dielectric fused silica or polystyrene microspheres with diameters ranging from 0.5 to 7.5 μm. The excited light scatted in the film is collected by the microspheres to stimulate whispering gallery modes, by which the internal quantum efficiency of spontaneous emission is enhanced. Meanwhile, the microsphere monolayer efficiently couples emitted light energy from the luminescent film to the far-field for PL detection. A UV-PL enhancement up to 10-fold via a 5-μm-diameter microsphere monolayer is experimentally demonstrated in this work. The unique optical property of microsphere in photoluminescence(PL) enhancement makes them promising for high-sensitivity PL measurements as well as design of photoelectric devices with low loss and high efficiency.Finally, we discussed the electro-optical properties of ZnO(film, single crystal and GZO) after laser irradiation. Photoluminescence and UV-VIS spectra show that the bandgap of ZnO thin film was smaller after laser irradiation. UV emission could be fitted by FX, neutral donor bound exciton(D0X) and neutral donor bound exciton first-order phonon tracing line(D0X-1LO) three parts at room temperature. The visible emission of ZnO thin films can be attributable to VO+, VZn, Oi and Vo++. The carrier concentration of ZnO thin film increased two orders of magnitude, carrier mobility increased by one order of magnitude, resistivity decreased by 3 orders of magnitude after laser irradiation. The crystallization of ZnO single crystal quality change is small, there are no obvious crack on the surface. After laser irradiation, the resistivity of ZnO single crystal decreased by two orders of magnitude, carrier concentration increased by one order of magnitude. The UV emission of ZnO single crystal has been enhanced and the visible emission has been decreased after irradiation. Changing the number of laser pulses can effectively control the Zn O single crystal emitting light colors. The photoelectric properties of GZO single crystal did not change after KrF excimer laser irradiation.
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