• Kumar, S.; Tessarek, C.; Sarau, G.; Christiansen, S.; Singh, R.: Self-Catalytic Growth of β-Ga2O3 Nanostructures by Chemical Vapor Deposition. Advanced Engineering Materials 17 (2015), p. 709–715

10.1002/adem.201400289

Abstract:
In this work, we have studied the synthesis of single crystalline self-catalyzed beta gallium oxide (β-Ga2O3) nanostructures by chemical vapor deposition technique. We have adopted a new approach to grow the nanostructures instead of using conventional foreign metal nano-catalyst based-approaches. The as-grown nanostructures including nanowires and nanosheets (NSHs) were grown on spin-coated Ga2O3 films. The structural studies such as X-ray diffraction, Raman and transmission electron microscope (TEM) investigations on the nanostructures showed monoclinic phase of Ga2O3 and single crystalline structure. Furthermore, high-resolution TEM with a selected area electron diffraction pattern recorded on a single β-Ga2O3 nanowire and nanosheet verified their single crystalline nature, having [001] as favorable growth direction. The energy dispersive X-ray spectroscopy-elemental mapping of as-grown nanostructures indicated uniform distribution of Ga and O. Cathodoluminescence imaging and spectrum revealed excellent luminescence characteristics of nanostructures with a broad UV-blue emission band (1.80–4.20 eV nm) centered at 2.64 eV. This study also highlights the growth mechanism of NSHs. These β-Ga2O3 nanostructures have great potential in nanofunctional devices.