Tetrapod zinc oxide (T-ZnO) nanorods have been synthesized by evaporation and recondensation of metallic Zn under ambient conditions. The total sizes of the T-ZnO nanostructures range from 300nmto15μm with leg diameters of about 30to650nm, depending on the deposition temperature. A detailed high-resolution electron microscopy analysis showed that the center core of T-ZnO nanorods consists of four hexagonal grains with a twinlike relation. The nucleation and growth mechanism has been generated on the basis of energy considerations during a phase transition from a fullerenelike ZnO cluster to a nanometer-sized tetrahedron, which is directly visible in our high-resolution transmission electron microscopy investigations.

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Three broad cathodoluminescence bands centred at ∼2.02 eV (red), ∼2.78 eV (blue), and ∼3.45 eV (ultraviolet) have been observed from silica nanowires synthesized by thermal evaporation at high temperature. The luminescence intensities of both the red and ultraviolet bands decrease upon electron-beam irradiation, while the intensity of the blue band increases with both irradiation time and specimen temperature. The red, blue, and ultraviolet bands are identified as radiative transitions involving the following centres: nonbridging oxygen hole centres, oxygen-deficient centres, and peroxy linkage. The varying time- and temperature-dependent luminescence intensities can be explained by the mutual transformation of these defects, which is driven by the irradiation- and heat-induced migration and desorption of radiolytic oxygen.

Amorphous carbon thin films containing 0–50 at. % Cu have been grown by mass selected ion beam deposition in order to synthesize isolated Cu nanoparticles within a diamond-like matrix. Raman spectroscopy and x-ray photoelectron spectroscopy show that the sp3 content of the matrix decreases with increasing Cu content. Simultaneously, the mean particle size of the embedded Cu nanocrystals increases, as x-ray diffraction and transmission electron microscopy analysis reveal. There is apparently no dependence of the matrix structure on the Cu+ ion energy, while the Cu content is strongly influenced by this deposition parameter.

p -type conduction in hexagonal boron nitride (hBN) films was achieved by beryllium implantation and subsequent rapid thermal annealing treatment. The dependence of phase composition and electrical properties of hBN films on the implantation fluence and annealing was studied. A maximum resistivity reduction by six orders of magnitude was demonstrated. Hall measurements revealed a corresponding hole concentration of 3×1019 cm−3 and mobility of 27 cm2/V s. The activation energy of Be ions was estimated to be 0.21 eV. It is suggested that hBN is a promising wide bandgap semiconductor for applications in high-temperature electronic devices and transparent conductive coatings.