Sustainable ITO films with reduced indium content deposited by AACVD

Abstract

Investigation of novel and high-performance transparent conducting electrodes (TCEs) is required to substitute currently widely used tin-doped indium oxide (ITO) due to the low abundance of indium and constantly increasing demand on ITO in the optoelectronic device industry. Here we synthesise In–Sn–O thin films from inexpensive and air-stable precursors by aerosol-assisted chemical vapour deposition (AACVD). These films presented excellent electro-optical properties, of which the optimum sample possessed a low resistivity of 8.7 × 10⁻⁴ Ω cm and an optical transmission (∼80%) across the visible light spectrum, which is similar to current industry standards. Analysis of the film elemental composition revealed considerably lower indium content (70 at%) as compared to those in commercial ITO (commonly >90 at% of indium). Scanning electron microscopy (SEM) images displayed dense and continuous crystal grains with uniform film thickness. This work shows the promising potential of AACVD to prepare more sustainable alternatives to ITO under simple, safe and cost-effective conditions.