Transparent and conductive titanium indium zinc oxide/Ag/titanium indium zinc oxide multilayer films deposited by radio frequency magnetron co-sputtering

Abstract

Multilayer transparent films with lower electrical resistance than the widely used transparent conductive electrodes, were prepared at room temperature on flexible PES [poly(ether sulfone)] substrates using an RF-magnetron co-sputtering system. The multilayered films consisted of three layers, titanium indium zinc oxide (TIZO)/Ag/TIZO. The optical and electrical properties of the multilayered TIZO/Ag/TIZO structure were investigated in relation to the thickness of each layer. A transparent and conductive film with a sheet resistance of 7.7Ω/□ and an average transmittance of 92% (normalized to the flexible PES substrate) at 550nm, was obtained at thicknesses of PES/TIZO(100nm)/Ag(10nm)/TIZO(40nm). The surface roughness (root mean square, RMS) values of the obtained multilayer films were below 1nm. Overall, the properties of the film were comparable or superior to those of other multilayer films such as indium tin oxide (ITO)/Ag//ITO, indium zinc oxide (IZO)/Ag/IZO, and indium zinc tin oxide (IZTO)/Ag/IZTO. For this reason, the new TIZO/Ag/TIZO multilayer film may serve as a viable, high-efficiency alternative for electrode applications in flexible photovoltaic cells.