Selective-area Growth of Gallium Oxide Nanowires:Synthesis, Characterization, and Device Application

In this paper, we report the selective area synthesis of gallium oxide (Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) nano-wires on gold patterned gallium arsenide (GaAs) substrate which have been treated by ion implantation. The GaAs substrate was first treated with implantation of acetylene (C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) ions, and then followed by coating the surface with a 2nm thick gold film. After rapid thermal anneal (RTA) at 950degC for 15 seconds, Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> nanowires were found on gold patterned surface. The Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> nanowires with diameters of 50-500nm were examined by Raman spectroscopy, scanning electron microscopy (SEM), and cathodoluminescence (CL). We also measured the I-V behavior for Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> material under the excitation by various laser radiations, hence demonstrating its potential applications as UV sensors. In addition, nano-particles of gold were found at the tip of the nano-wires, suggesting that a vapor-liquid-solid (VLS) mechanism was involved.