Low Resistivity-Highly Transparent Zno:Ga Tco's Grown by Laser Ablation

Abstract

ABSTRACTHighly transparent with low electrical resistivity gallium-doped zinc oxide (ZnO:Ga) thin films were prepared on glass by Pulsed Laser Deposition at different substrate temperatures. ZnO:Ga evaporation targets were prepared by pressing and sintering powder materials obtained with a novel combustion synthesis technique.An excellent transmittance of more than 85% in the visible range and a low sheet resistance value as low as 13 Ω/sq. were measured on a 200 nm thickness film grown at Ts=300°C. From optical measurements we observed an increase in the ZnO:Ga bandgap when the substrate temperature is raised from 150°C to 300°C. With this, a remarkable improvement in the blue-green region transmittance is obtained.X-Ray diffraction patterns indicate that the films grow highly oriented in the basal plane direction (c-axis) of the hexagonal ZnO grains.