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  • 1 Budapest University of Technology and Economics, Department of Electronics Technology, H-1111 Budapest, Goldmann Gy. tér 3.
  • 2 University of Debrecen, Department of Experimental Physics, H-4026 Debrecen, Bem tér 18/a, Hungary
  • 3 University of Debrecen, Department of Solid State Physics, H-4010 Debrecen, POB 2, Hungary
  • 4 University of Debrecen, Department of Experimental Physics, H-4026 Debrecen, Bem tér 18/a, Hungary
  • 5 Institute of Technical Physics and Material Sciences of the Hungarian Academy of Sciences, Please ask the editor of the journal.
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We present a simple method of nanocrystal growth during the heating of Au-covered GaAs single crystals in a closed quartz ampoule, previously evacuated to 10-1 Pa. The process is the final stage of surface transformations in such crystals which include the disruption of initially continuous, 50 nm thick Au layer and formation of Au-particle fractals in the relatively low 300-500 °C temperature range and a next step, when a variety of crystalline nanowires and even nanotubes grows on the crystal surface during the further short-period heating up to 550-650 °C. These nanostructures were identified by SEM and TEM measurements as b-Ga2O3 and a non-stoichiometric arsenic oxide. It is supposed that the growth of few nanometer thick arsenic oxide tubes follows the vapour-solid mechanism, whereas the catalytic Au-metal growth of thicker b-Ga2O3 nanowires was dominated by the vapour-liquid-solid mechanism.