Index-matched indium tin oxide electrodes for capacitive touch screen panel applications

Index-matched indium tin oxide (ITO) electrodes for capacitive touch screen panels have been fabricated to improve optical transmittance and reduce the difference of reflectance (□R) between the etched and un-etched regions. 8.5 nm Nb₂O₅ and 49 nm SiO₂ thin films were deposited by magnetron sputtering as index-matching layers between an ITO electrode and a glass substrate. In case of 30 nm ITO electrode, a 4.3% improvement in the optical transmittance and a □R of less than 1% were achieved, along with a low sheet resistance of 90 Ω/□.