One-dimensional quantum wires are expected to play important role in future electronic and optical devices. We have investigated semiconducting nanowires made by a novel supercritical fluid solution-phase technique [1]. Conductivity and force interactions in individual semiconductor nanowires were investigated by using an in-situ probing technique using a TEM-SPM [2,3], which is a combination of the scanning probe microscope (SPM) and the transmission electron microscope (TEM). Free standing Si nanowires were high resistive with exhibited metallic behaviour. Nonconductive gap was observed in Ge nanowires. The electromechanical properties of these wires were characterised and a prototype nanorelay was demonstrated.
Uniform mesoporous thin films, with pores orientated almost perpendicular to the substrate surface are used as templates for unidirectional semiconducting nanowire growth. Structure of films and polycrystalline material containing Si and Ge nanowire arrays was investigated [4]. Luminescence of mesoporous nanowires was determined, as function of nanowire size. The optical properties can be controlled by the effective change of pore size inside mesoporous silica.
Quantum-chemical simulation of the silicon nanowires is carried out by semi-empirical CLUSTER code.