Fabrication and application potential of ZnO nanowires grown on GaAs(002) substrates by metal-organic chemical vapour deposition

ZnO nanowires were grown on GaAs(002) single-crystal substrates using metal-organic chemical vapour deposition. X-ray diffraction analysis, scanning electron microscopy and photoluminescence spectroscopy were carried out to characterize their crystallinity, orientations, dimensions and optical properties. It was demonstrated that well aligned arrays of single-crystalline ZnO nanowires with sharp tips could be grown on GaAs substrates using a typical thin film deposition technique without catalysts. The application potential of the nanowires as probes of atomic force microscopes (AFMs) was then discussed by predicting their structural compatibility with AFM cantilevers based on continuum elasticity and finite element analysis. Theoretically estimated mechanical properties of the ZnO nanowires suggested that they are structurally compatible with typical AFM cantilevers while maintaining mechanical stability during operation and they are therefore promising candidates for high aspect ratio probes.