Low resistivity ITO film prepared using the ultra high density ITO target

Abstract

The ultra high density ITO target of 99% or more in relative density has developed by the improvements of the ITO powder and the sintering process. Sputtering test on various densities (90, 97 and 99%) of ITO (SnO₂: 10 wt.%) targets was performed in a dc magnetron sputtering system. The minimum resistivity of the thin film was obtained at 0.1% in O₂/Ar for each of the targets, and was 149 (μΩ×cm) for the 99% target, 159 (μΩ×cm) for the 97% one and 161 (μΩ×cm) for the 90% one, respectively. Hall effect measurement revealed that the improvement of the resistivity with an increase in the target density is due to the carrier concentration increase. ITO films prepared with different density targets were analyzed by means of EPMA, SEM, XRD and ESCA. However, no differences in microstructure were recognized between them.