抄録
Zinc oxide is a highly attractive material for fabrication of novel UV lasers. We recently discovered that many kinds of ZnO crystals grow on a ZnO ceramic bar heated by electric current (Joule heating). We named the technique ″Electric Current Heating Method″. The advantages of this method are that various crystals such as whisker, tetrapod and double-hollow prism can be fabricated, without special equipments or catalysts, solely by changing the electric current, atmosphere and relative density of a ZnO ceramic bar. Nanowhiskers tended to grow under the atmosphere with low oxygen partial pressure. The diameters and lengths of the nanowhiskers were a few hundred nm and a few hundred μm, respectively. Photoluminescence of the nanowhiskers was investigated at 15 K. Clear exciton emissions at UV region and the extremely weak deep-level emission at visible region were observed from the nanowhiskers, reflecting high-crystalline quality.
