Characteristics of transparent conductive Al-doped ZnO and Ag-Ti tri-layer thin films prepared by multi-target magnetron sputtering

Al-doped ZnO (AZO) and Ag-Ti films were successfully deposited on glass substrates by multi-target magnetron sputtering to form the high transparent AZO/Ag-Ti/AZO multilayer. The optical, electrical properties and lifetime performance were investigated at various AZO and Ag-Ti thicknesses. As the AZO thickness was fixed at 10 nm and Ag-Ti thickness was varied between 6 and 22 nm, it can be found that AZO(10) (nm)/Ag-Ti-10 (nm)/AZO(10) (nm) possessed good conductivity and highest transmittance in visible region. Then an AZO thickness adjustment of 10-90 nm was performed. With increasing AZO thickness from 10 to 70 nm, the transmittances of AZO(10-70) (nm)/Ag-Ti-10 (nm)/AZO(10-70) (nm) films were all above 80% in the visible region and optimal transparency can be reached at AZO thickness of 70 nm. Although the conductivity in AZO/Ag-Ti/AZO films was decreased with increasing Ag-Ti thickness, the resistivity of 4.95 x 10-(4)Omega-cm in AZO(70) (nm)/Ag-Ti-10 (nm)/AZO(70) (nm) was still acceptable. From the lifetime tests under normal circumstance, these multilayers almost showed the same transmittance and resistivity from 0 to 90 days. Furthermore, the AZO(70 nm)/Ag-Ti-10 nm/AZO(70 nm) exhibits the highest figure of merit of 8.93 x 10(-3) Omega(-1), indicating that the multilayer has high potential in optoelectonic applications. (c) 2013 Elsevier B.V. All rights reserved.