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PACS 78.55. 81.05.Dz, 82.80.Pv, 85.60.Jb ZnO films were fabricated by spin coating. The photoluminescence (PL) spectra of the films, which included a near-band-edge emission, were observed at RT. The estimated external quantum efficiency of their PL is approximately 1.2%. Electroluminescent devices (ELDs) using the ZnO films were also fabricated. The violet light emission was observed from the devices. The results indicate that the spin-coated ZnO films have high potential for application to UV light-emitting devices. In this study, the spin-coating fabrication of ZnO films deposited on tantalum oxide (Ta 2 O 5 ) insulators (thickness: 150 nm), which were coated on Si substrates, is reported. The photoluminescence (PL) spectra of these ZnO films were observed at RT and their emission efficiency was estimated. Electroluminescence devices (ELDs) were also fabricated using the ZnO films. Finally, the possibility of spin-coated ZnO films for application to light-emitting devices is discussed.

Electroluminescent devices (ELDs) were fabricated using GaNO crystallites. The GaNO crystallites were obtained by the oxidation of GaN crystallites before their annealing in vacuum. Although the cathodoluminescence spectra of GaNO crystallites were broad compared with those of GaN crystallites, the spectral intensities of GaNO crystallites are higher than those of GaN crystallites. In the fabrication of lightemission layers in the ELDs, sedimentation with the selection of GaNO crystallite size was performed. The size selection of GaNO crystallites is effective for the realization of thin and uniform emission layers. It leads to the reduction of operating voltage.

The cathodoluminescence (CL) of GaN crystallites with and without surface oxide layers is reported. The CL intensity of the coated GaN crystallites is higher than that of the crystallites without oxide layers although the shapes of the coated GaN crystallites are similar to those of uncoated GaN crystallites. The surface coating with gallium oxide is effective for the reduction of surface recombination in GaN crystallites. Electroluminescent devices (ELDs) using GaN crystallites covered with gallium oxides were fabricated. UV light emission was observed from the GaN‐based ELDs at RT. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)