Synthesis And Optical Characteristic Of ZnO Nanostructures And Films

ZnO is a direct wide band gap compound semiconductor,E_g=3.37eV at room temperature,it has a large exciton binding energy about 60meV.In recent years,ZnO nanostructures have attracted much attention due to their potential applications in a wide range of advanced devices.ZnO nanostructures have become promising candidates for applications in blue-ultraviolet light emitting,field-effect transistor(FET) and transparent conductivity.Furthermore,ZnO nanostructures can be used for electromechanical coupled sensor,transducers and biomedical applications.In this paper,many kinds of ZnO nanostructure have been prepared by pulsed laser deposition technique on InP subatrate. ZnO:Al thin films have also been fabricated by reactive radio frequency magnetron sputtering on InP substrate at different temperature.Scanning electron microscopy(SEM),X-ray diffraction(XRD),photoluminescence(PL) spectra,energy-dispersive X-ray(EDAX),atom force microscopy(AFM) are adoped to characterize the properties of the samples.Ⅰ.Well-aligned ZnO nanorod arrays were successfully fabricated on InP(001) substrate using pulsed laser deposition(PLD) technique at 400℃,the ZnO nanorod exhibits a strong c-axis orientation with high crystalline quality and well optical quality.ZnO:P nanorods were also synthesized at 500℃.Indium element diffused in to ZnO nanowire and formed ZnO:In at the temperature higher than 500℃.Ⅱ.High-density well-aligned ZnO nanotube was prepared on InAs substrate at 650℃.SEM image showed that uniformly distributed nanotube was formed perpendicular to the InAs wafer and well separated from each othrer.The results denoted that crystalline quality was well at 650℃.Indium element diffused in to ZnO and formed ZnO:In nanostructure.Ⅲ.ZnO:Al thin films were prepared by reactive radio frequency magnetron sputtering at different temperature.The measurement results illuminated that the crystalline quality and optical property are increasing with increase temperature of substrate,the properties is the best at 550℃.When continuely increase temperature,the properties decreased.