Controlled formation of well-aligned GaAs nanowires with high aspect ratio on transparent substrates

摘要

In this study, we present a facile route to fabricate large-scale arrays of GaAs nanowires (NWs) with high aspect ratio on transparent substrates. It is demonstrated that the monolayer of SiO_2 nanoparticles can be effectively used as etch masks for the inductively coupled plasma (ICP) etching process. To form the monolayer of SiO_2 nanoparticles on the GaAs substrate, the concentration and temperature of the SiO_2 colloidal dispersion solution as well as the interface wetting of the GaAs substrate are investigated. By adjusting the ICP etching conditions, the high-aspect-ratio GaAs NWs with lengths of 4.3μm and cross-sections of 70nm are successfully fabricated. Furthermore, the fabricated GaAs NWs are massively transferred onto the transparent substrate at low temperature. The SEM observation and the X-ray diffraction spectrum reveal that the transferred GaAs NWs have vertically aligned morphology and good crystal property.