Intrinsic and Doped Zinc Oxide Nanowires for Transparent Electrode Fabrication via Low-Temperature Solution Synthesis

Undoped and doped zinc oxide (ZnO) nanowires were synthesized by decomposing metal salts in trioctylamine at 300C. By adding metal salts during the formation of the wires, effective incorporation of Ga and Al up to 5% was achieved, as measured by energy-dispersive x-ray spectroscopy and Auger electron spectroscopy. No secondary phase was detected by high-resolution transmission electron microscopy and x-ray diffraction. The nanowires were single-crystalline with a wurtzite lattice structure. Films made with doped wires show a complex dependence of the sheet resistance on processing conditions and dopant concentration. Thermal annealing treatment reduced the sheet resistance to values of 10 3 X/square.