Electrical and Optical Properties of Solution-Based Sb-Doped SnO2 Transparent Conductive Oxides Using Low-Temperature Process

Abstract

Solution-based Sb-doped <TEX>$SnO_2$</TEX> (ATO) transparent conductive oxides using a low-temperature process were fabricated by an electrospray technique followed by spin coating. We demonstrated their structural, chemical, morphological, electrical, and optical properties by means of X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, atomic force microscopy, Hall effect measurement system, and UV-Vis spectrophotometry. In order to investigate optimum electrical and optical properties at low-temperature annealing, we systemically coated two layer, four layer, and six layers of ATO sol-solution using spin-coating on the electrosprayed ATO thin films. The resistivity and optical transmittance of the ATO thin films decreased as the thickness of ATO sol-layer increased. Then, the ATO thin films with two sol-layers exhibited superb figure of merit compared to the other samples. The performance improvement in a low temperature process (<TEX>$300^{\circ}C$</TEX>) can be explained by the effect of enhanced carrier concentration due to the improved densification of the ATO thin films causing the optimum sol-layer coating. Therefore, the solution-based ATO thin films prepared at <TEX>$300^{\circ}C$</TEX>C exhibited the superb electrical (<TEX>${\sim}7.25{\times}10^{-3}{\Omega}{\cdot}cm$</TEX>) and optical transmittance (~83.1 %) performances.