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Single quantum dots (QD) luminescence from MBE-grown CdSe/ZnSe QD was observed by micro-cathodoluminescence measurement. The scanning area of the exciting electron beam was decreased from 100 × 100 μm2 to 0.2 × 0.2 μm2. A broad emission was observed till an area of 2 × 2 μm2, and sharp emission lines were clear at a scanning area of 1 × 1 μm2 or less. The spatial resolution of this measurement was determined to be 0.45 μm from the number of sharp lines and the QD density. The luminescence intensity mapping was performed at arbitrarily selected wavelengths, and QD existence was clearly shown at different positions at each wavelength. Thus, the luminescence observation of the CdSe single QD and its mapping were successfully performed by micro-cathodoluminescence measurement for the first time. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

InN/Si heterojunctions consisting of InN with an oxygen concentration of ∼3% and a bandgap of 1.8 ∼ 2.0 eV were formed by MBE. The band alignment of the heterojunctions turned out be type II with a band discontinuity of 1.49 ∼ 1.60 eV. A SiNx intermediate layer with a thickness of 2.1 nm was observed by angle-resolved X-ray photoemission spectroscopy. The heterojunction showed good rectifying characteristics with a reverse current of 1 × 10−7 A/cm2. Separation of the InN/Si interface and the p–n interface by insertion of n-Si layer with a thickness of 200 nm resulted in a reduction of the reverse current in the heterojunction.