The Study On Zinc Oxide Micro/nanowire Based Photoelectric Device

Ultraviolet light-emitting and laser have important applications in greenlighting, optical communication and optical information storage. II-VI groupsemiconductor zinc oxide is a wide direct band gap semiconductor (3.37eV) withhexagonl wurtzite structure, and also it has a large exciton binding energy of60meV,which makes the excitons thermally stable at room temperature because the value ismuch larger than the thermal energy of26meV, is a promising candidate material forultraviolet light emitting diodes and lasing diodes at room temperature. Meanwhile,ZnO raw material is abundant, non-toxic and so on. So ZnO is an important materialfor semiconductor untraviolet laser, which has been the new hot spot in theshort-wavelength semiconductor laser materials and device research following theGaN material. In this thesis, focusing on the controllable growth of ZnOmicro/nanostructures, the design, preparation light emitting and laser devices of ZnOmicrowire to carry out research work, and made the following innovative researchresults:1. The ZnO microwires with the quadrate cross section were obtained bychemical vapor deposition method, the width is about7μm, and the length is about1cm. The ultraviolet stimulated emission of F-P cavity modes were observed withthreshold intensity of58kW/cm2excited by femtosecond laser in the opticallypumped single ZnO microwire. 2. Preparing the single ZnO microwire/GaN heterostructure using the p-GaN asthe hole injection layer, the UV electrically pumped stimulated emission originatedfrom the ZnO microwire was obtained, and the full width at half maximum (FWHM)was0.2nm.3. Preparing the MS junction light emitting diodes based on single ZnOmicrowire, the metal Au was use as electrodes. The turn-on voltage of this devicewas5V, and the visible region (400to700nm) electroluminescence was realized.4. Exploring hydrothermal treatment method to obtain p-type ZnO film, andverifying the films were p-type conductivity through low-temperature luminescencespectroscopy, Hall measurement and prepare the diode method and so on. This workis published in the Appl.Phys.Lett. and is Top20most downloaded articles in APL inFebruary2011.