9:45 AM - 10:00 AM
▼ [17a-502-4] Au/Mo-catalyzed Vapor-Liquid-Solid Growth of InGaZnO Nanowires from Amorphous Thin Film
Keywords:InGaZnO, nanowires, VLS growth
InGaZnO (IGZO) is gaining interest as a material of choice for various electronic applications owing to its superior carrier mobility, stability, low-temperature process, and optical properties. However, only few reports on nanostructured IGZO were presented, and their fabrication methods require complicated steps and high annealing temperatures. In this study, the direct growth of high aspect ratio IGZO nanowires via a facile Au/Mo-catalyzed VLS process is reported. Pre-cleaned quartz glass substrates were used to deposit 200 nm of amorphous IGZO thin film via RF sputtering using sintered (In:Ga:Zn ~2:2:1) targets at room temperature. Thin film strips of Mo (100 nm) and Au (20 nm) were then deposited perpendicular to each other across the a-IGZO layer. Annealing was performed under 5.0 slm N2 atmosphere at 700°C for 2 h. The SEM image revealed that the nanowires grew on the surface of the Mo thin film, at the edge of the Mo/Au overlap. There were no nanowires on only Au or Mo area. The lengths of the nanowires ranged from 1.5-4.0 µm, while the diameters are about 60 nm. A nanoparticle is seen attached to the nanowire tip, which suggests that VLS growth is the probable growth mechanism by which the nanowires grew. EDX line profile confirmed the composition of the nanowires to be InGaZnO, with Au and Mo at the tip.