Transparent Conducting Oxides SrNbO3 Thin Film with Record High Figure of Merit

Abstract

Transparent conducting oxides are crucial in the field of optoelectronics, and SrNbO3 has emerged as a promising candidate because it can outperform commonly used indium tin oxides due to its novel functionality. However, experimental investigations of SrNbO3 are challenging because it undergoes topotactic phase transition to exhibit insulating behavior. Here, we investigate the pivotal role of SrNbO3 stoichiometry to enhance its performance as a transparent conducting oxide. Results indicate the optoelectronic properties of SrNbO3 are highly dependent on its intrinsic lattice parameters and stoichiometry. Films with lattice parameters close to those of pure SrNbO3 exhibit excellent conductivity and transmittance in the visible range, while off-stoichiometry diminishes optoelectronic properties. Our stoichiometric sample demonstrates a record-high figure of merit for SrNbO3, considerably surpassing that of indium tin oxide by an order of magnitude. Thus, this study paves the way for production of high-quality SrNbO3 and leveraging its novel functionalities in optoelectronic applications.