Assessment of Optoelectronic Properties in ZnO-Ag(NPs)-ZnO Trilayer Thin Films Deposited by RF Sputtering

Abstract

This study investigates the optoelectronic properties of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Z n O} / \mathbf{A g} / \mathbf{Z n O}$</tex> tri-layer thin films deposited by RF sputtering and benchmarks their performance against commercial, high-cost Indium Tin Oxide (ITO). Post-deposition, the structure was annealed at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{3 0 0}^{\circ} \mathrm{C}$</tex> for 30 minutes to promote the formation of silver nanoparticles within the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Z n O}$</tex> matrix. Optical characterization reveals that while ITO maintains high transparency in the visible to near-infrared (NIR) range and strong UV absorption, the ZnO/Ag(NPs)/ZnO films exhibit both intrinsic UV absorption from ZnO and a distinct visible light absorption peak resulting from Surface Plasmon Resonance (SPR) induced by embedded silver nanoparticles. Electrical measurements confirm ITO's superior conductivity; however, the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{Z n O} / \mathbf{A g}$</tex> (NPs)/ZnO tri-layers demonstrate a favorable balance between transparency and conductivity, attributed to their engineered multilayer structure and plasmonic enhancement. These findings highlight the potential of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{ZnO} / \text{Ag}$</tex> (NPs)/ZnO thin films as a costeffective and tunable alternative to conventional ITO for transparent conductive applications.