Ordered silicon nanowires (SiNWs) with single crystal structure were synthesized using nanochannel-Al2O3 (NCA) and the chemical vapor deposition (CVD) method. Firstly, the SiNWs with nearly amorphous structure were fabricated at 500℃; then the SiNWs with crystalline structure were obtained by annealing an as-received sample at 800 C. The average diameter and length of the SiNWs are 40-70 nm and 10 mm, respectively. The Raman shift related to the crystallization and the amorphous SiNWs was analyzed.

Aligned single crystal superconducting MgB2 nanowires were synthesized on nano-channel-Al2O3 (NCA) substrates. At first, aligned single crystal boron nanowires were prepared by the chemical vapour deposition process. Then magnesium was incorporated in a sealed vacuum quartz tube to form aligned single crystal superconducting MgB2 nanowires. The diameters of the MgB2 nanowires were in the range of 20-150nm. Finally, there are indications that the nanowires had a superconducting transition temperature (Tc) at ～33 K.

Non-filled MgO nanotube bundles have been fabricated via a thermal evaporation method using Mg strips as the source material. The samples were characterized using x-ray diffraction, scanning electron microscopy and transmission electron microscopy. The as-synthesized nanotubes self-assembled into bundles, and the nanotubes in a bundle had the same growth direction. The nanotubes are about 100 nm in diameter and several micrometres in length. The possible growth process for the MgO nanotube bundles has been discussed.

The thermal stability of oxygen precipitates formed by prolonged annealing at 1000℃ in conventional Czochralski silicon and nitrogen-doped Czochralski silicon has been comparatively investigated. It was found that a majority of the existing oxygen precipitates in the nitrogen-doped silicon were dissolved by both conventional furnace annealing and rapid thermal annealing at 1200℃, while those in the conventional Czochralski silicon dissolved at 1250℃, as a result of nitrogen enhancing denser oxygen precipitates with smaller size. Furthermore, it can be considered that the dissolution of oxygen precipitates is primarily determined by the annealing temperature.

Array-ordered single-crystal silicon nanowires were fabricated by the nanochannel-aluminal and CVD method. The average length and diameter of the nanowires is about 10 mm and 60 nm, respectively. A study of the Raman spectrum of the nanowires shows that the Raman shift to low frequency is due to the quantum confinement effect, which is discussed by using the phonon confinement model. Also we determine the peaks of the Raman spectrum to be corresponding to that of crystal silicon (c-Si).