Investigation on optical and electrical properties of Cu/Au/ITO transparent conductive films

Asymmetric Cu/Au/ITO tri-layer films are deposited on glass substrate by magnetron sputtering, the effect of Au and tin indium oxide (ITO) layers on the optical and electrical properties are studied systematically. The Cu/Au bi-layer films with a thickness of ~ 20 nm Au layers show low sheet resistance of 32.40 Ω/sq. and high transmittance of 84.5% at 550 nm. The addition of top ITO layer can effectively reduce sheet resistance. After 100 nm thick ITO layer is added, the sheet resistance reduces to 23.38 Ω/sq. without obvious decrease in the transmittance. Which attributes to the high carrier concentration (2.62 × 1021 cm−3) which originates from the injection of electrons from Au layer to ITO layer. This asymmetric Cu/Au/ITO tri-layer can be a good alternative for the common ITO electrodes.