Whispering gallery and Fabry-Perot modes enhanced luminescence from individual ZnO micro mushroom

One kind of micro structures, ZnO mushrooms, have been synthesized by self-assembled method on single silicon substrates with Au catalyst assisted thermal evaporation of ZnO and active carbon powders. Cathodoluminescence for individual ZnO micro mushroom has been invested. The luminescence from the center region is attributed to the Fabry-Perot mode enhanced emission, and the one from the hexagonal profiles is attributed to the whispering gallery mode enhanced emission when the individual ZnO micro mushroom is regarded as an optical resonator. The field-emission property of these ZnO micro mushrooms has been measured and the turn-on electric field is 5.9 V/mu m. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4780226]