LUMINESCENCE OF ZnO WHISKERS GROWN ON Au SURFACE BY ELECTRIC CURRENT HEATING: EFFECT OF THE DENSITY OF ZnO CERAMIC BAR

摘要

We have recently developed a new ZnO crystal growth process using Au combined with electric current heating. Au paste was placed on a ZnO ceramic bar. When a certain current flowed through the bar, the paste melted and became spherical on the bar. Then novel crystals were grown on the Au. The relation between the relative density of the ZnO ceramic bar and luminescence from the grown crystals was investigated. ZnO whiskers with spherical Au top were grown on Au surface in air. The diameter of the whiskers grown by electric current heating for porous ceramics was smaller than that for dense one. The whiskers grown for dense ceramics exhibited a weak ultraviolet emission at approximately 3.3 eV and green emission at approximately 2.3 eV, while the spectra of the whiskers grown for the porous ceramics were dominated by ultraviolet emission.