Germanium catalyzed amorphous silicon dioxide nanowire synthesized via thermal evaporation method

Summary for only given. One-dimensional (1D) nanostructures have been attracting great interest because they have opportunities for potential applications in nano-electronics and optoelectronics. SiO₂ has attracted great attention due its potential application such as laser emitter, panel displays and sensors [1], Various SiO₂ nanowires have been produced by several methods, mostly vapor-liquid-solid (VLS) mechanism using different metal catalyst including thermal evaporation [2-4], chemical vapor deposition [5] and laser ablation [6]. Recently, Liu et al. [7] have studied the magnesium catalyzed growth of SiO₂ hierarchical nanostructures by a thermal evaporation process. In this paper we report a simple thermal evaporation technique (horizontal tube furnace) to grow the bulk-quantity of the Ge-catalyzed amorphous SiO₂ nanowires on the Si substrate by using germanium (Ge) powder as catalyst. The nanostructure and optical properties of the Ge-catalyzed amorphous SiO₂ nanowires have been investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-Ray diffraction (XRD) and photoluminescence (PL) spectroscopy. The investigation of structural properties indicated that the structures consist of SiO₂ nanowire with diameters around 70-400 nm and length of about 2-40 μm (Figure 1). EDX reveals that the nanowires structures have Ge, Si and O₂ compositions and XRD analysis confirmed the product is typical amorphous structure. Room temperature photoluminescence (PL) spectrum (Figure 2) shows emission peak was at about 390 nm, opening up a route to potential applications in future optoelectronic devices.