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Discusses a study that produced amorphous aluminum oxide layers by oxidizing amorphous aluminum (Al) and arsenic (As) compounds using water vapor. How water vapor was created; Use of the Auger electron spectroscopy in the study; Application of the transmission electron microscopy (TEM).

Presents information on a study which investigated the microstructure of nominally undoped epitaxial wurtzite-structure amorphous-GaN (α-GaN) films. Description of high-resolution transmission electron microscopy images; Relationship between the ordered defects and the carrier concentration observed in the materials; Primary extended defects observed in as-grown α-GaN films.

Large-area arrays of copper oxide (CuO) nanorods were self-catalyzed and selectively grown on a Cu/TaN/Si assembly by combining vacuum-arc Cu deposition and vapor-solid reaction. X-ray-diffraction spectra showed the peaks of Cu films and CuO nanorods, respectively. Field-emission scanning electron microscopy images showed semialigned CuO nanorods with diameters of ∼40–80 nm. High-resolution transmission electron microscopy images showed the structure of individual CuO nanorods and their [111] growth direction. Auger electron spectroscopy depth profiles showed the elemental distribution of the CuO/a-TaN/Si assembly. X-ray photoelectron spectrometry identified the chemical nature of the CuO nanorods. Their electron field-emission properties are discussed from the current-density–voltage curves and Fowler-Nordheim plots. [ABSTRACT FROM AUTHOR]

Structures and magnetic properties of Y2O3:Co nanocrystals were investigated using high resolution transmission electron microscopy, x-ray diffraction, x-ray absorption fine structures, and superconducting quantum interference device. Cobalt atoms were found to be driven by thermal annealing from interstitial locations inside the Y2O3 nanoparticles toward particle surface, where increased O vacancies surrounding Co atoms led to increased saturation magnetization. Our results strongly support a bound magnetic polaron model for ferromagnetism in diluted magnetic oxides mostly due to magnetic dopants located on the grain boundaries. [ABSTRACT FROM AUTHOR]

The growth of high-density Si nanorings has been achieved on ultrathin Au films on silicon substrate. Nanorings, which are gold-free and epitaxially grown on (001) Si, had a narrow distribution of height and diameter of 1.4±0.3 and 24.9±4.0 nm, with a density of 4.3×1010 cm-2. In situ ultrahigh-vacuum transmission electron microscopy revealed that the formation of nanorings involves a mechanism mediated by Au nanodots and evaporation of Au-Si eutectic liquid droplets at high temperature. The process promises to be an effective nanofabrication technique to produce high-density and uniform-sized nanorings. [ABSTRACT FROM AUTHOR]