Ultrasonic Spray Pyrolysis of Antimony‐Doped Tin Oxide Transparent Conductive Coatings

Abstract

AbstractTransparent conducting oxides are fundamental for the fabrication of optoelectronic devices including touchscreen displays, solar cells, and light emitting diodes. However, they mostly rely on rare elements and expensive vacuum‐based deposition methods that negatively affect the overall cost of optoelectronics. Here, a detailed investigation on the synthesis of antimony‐doped tin oxide films using an ultrasonic spray coating system is presented. High‐quality, crystalline SnO2 films are deposited via decomposition of metal precursors sprayed directly onto hot (>400 °C) substrates. Doping is easily achieved by adding the dopant salt to the spray solution, and the presence of the dopant atoms heavily influences the optical, electrical, and structural properties of SnO2. These coatings are characterized using a comprehensive suite of techniques including X‐ray diffraction, electron microscopy, X‐ray and ultraviolet photoelectron spectroscopies, Hall effect measurements, optical spectroscopy in the visible and near infrared, and atomic force microscopy, in order to elucidate the relationship between the synthetic conditions and functional properties. Through a careful optimization process, Sb‐doped SnO2 coatings showing transmittance values in the visible spectrum between 80% and 90%, and sheet resistances of 10–20 Ω/sq−1 are achieved. Such values are suitable for immediate applications of these Sb‐doped SnO2 films as high‐performance transparent conductors.