High transparent, low surface resistance ZTO/Ag/ZTO multilayer thin film electrodes on glass and polymer substrates

Zinc tin oxide (ZTO)/Ag/ZTO multilayer thin films were grown by direct current (DC) magnetron sputtering technique at room temperature on soda lime glass (SLG) and different polymer substrates such as polycarbonate (PC) and polyethylene terephthalate (PET) for transparent conductive electrode (TCE) applications. The effect of substrate on the structural, optical and electrical characteristics of ZTO/Ag/ZTO multilayers was investigated. All prepared ZTO/Ag/ZTO films presented amorphous structure as expected from room temperature deposition process and smooth surface quality with very low surface roughness. We found that ZTO/Ag/ZTO multilayer films grown on SLG, PET and PC substrates have very high optical transmission and low surface resistance. Moreover, after ZTO/Ag/ZTO multilayer thin film deposition on polymer substrates, the optical transmission was found to be enhanced because the higher absorption due to Ag layer is compensated by lower reflectance. Our results suggest that ZTO/Ag/ZTO multilayer thin films on any substrate can be a promising alternative to indium tin oxide (ITO) films as a cost-effective, indium-free, flexible and transparent electrode for various applications. •ZTO/Ag/ZTO electrodes were grown by DC magnetron sputtering at room temperature.•ZTO/Ag/ZTO thin films grown on SLG, PC and PET substrates were studied.•ZTO/Ag/ZTO electrodes are more transparent and conductive than conventional TCOs.•ZTO/Ag/ZTO on PC and PET show enhanced optical transmission due to the higher absorption and lower reflectance occurred in Ag.