Influences of the Ag and the ITO Thicknesses on the Optical and the Electrical Properties of ITO/Ag/ITO Multilayer Films

We studied the electrical and the optical properties of indium tin oxide (ITO) (t₁)/Ag (t₀)/ITO (t₂) (IAI) multilayer thin films based on the variations in the thicknesses of the Ag and the top and bottom ITO layers. The IAI multilayer thin films were deposited on soda lime glass (SLG) substrates by using radio-frequency and direct-current magnetron sputtering methods at room temperature. The deposited IAI multilayer thin films were analyzed using X-ray diffraction, UV-Visible spectroscopy, and Hall measurements. The optical transmittance at a wavelength of 550 nm was 91.7% for the IAI thin films having 9 nm-thick Ag and 50 nm-thick top and bottom ITO layers. The sheet resistance and mobility decreased with the increasing Ag thickness t₀ from 4.5 nm to 18 nm while they varied little with the thicknesses (t₁, t₂) of the top and the bottom ITO layers. The best optical and electrical performance of the IAI layer was obtained for the sample with 50 nm-thick top and bottom ITO layers (t₁ = t₂ = 50 nm) and the optimum Ag layer (t₀ = 9 nm).