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Room temperature electroluminescence has been demonstrated from undoped silicon nanowires that were grown from disilane. Ensembles of nanowires were excited by capacitively coupling them to an ac electric field. The emission peak occurred at about 600 nm from wires of average diameter of about 4 nm. The emission appears to result from band-to-band electron–hole recombination.

Graphene films were grown on nickel films and foils using chemical vapor deposition. To date, similar growth has been reported at around 1000 degrees C using methane or ethylene as source gases. However, by using acetylene, we have achieved growth of graphene films between 650 and 700 degrees C. The electrical and optical properties, including high resolution transmission electron microscopy of these films, suggest that this technique is both viable and scalable for potential large area optoelectronic applications.

Single-crystal SiGe nanowires were synthesized via the vapour-liquid-solid (VLS) growth mechanism using disilane and germane as precursor gases. We have investigated the effect of temperature, pressure, and the inlet gas ratio on the growth and stoichiometry of Si(x)Ge(1-x) nanowires. The nanowires were characterized using scanning and transmission electron microscopies and energy dispersive x-ray analysis. It was found that nanowires with a Si:Ge ratio of about 1 had smooth surfaces, whereas departure from this ratio led to rough surfaces. Electrical properties were then investigated by fabricating back-gated field effect transistors (using a focused ion beam system) where single SiGe nanowires served as the conduction channels. Gated conduction was observed although resistance in the undoped devices was high.