Optical and Electrical Properties of Annealed AZO/Ag/AZO Multilayer Deposited Using RF Sputtering Technique

This work aims at analyzing the effect of both Ag middle layer and annealing effects on the structural, optical and electrical properties of Al-doped ZnO (AZO) thin-films. In this framework, AZO/Ag/AZO tri-layers were deposited on glass substrates using RF magnetron sputtering technique. Structural, optical and electrical characterizations were carried out using XRD, UV-Vis Spectrophotometry and Hall measurements, respectively. The obtained XRD patterns demonstrated the enhanced crystallinity of the annealed AZO/Ag/AZO multilayer structure. In addition, transmittance spectra of prepared samples revealed the enhanced visible transparency of the annealed structure, showing a high average transparency of 85%. It is found also that the use of annealing and Ag middle layer can enlarge the band gap (3.53 eV). This is attributed to the increase of the free charge carrier, which can shift the Fermi Level. Electrical characterizations demonstrate that annealing process can modulate the electrical properties of the AZO/Ag/AZO thin-film, offering a high mobility of 17 cm
²
/Vs and a favorable sheet-resistance of 46 Ω/eq. Therefore, the present study can provide guidelines for the fabrication of alternative buffer layer, which can be appropriate for various thin-film solar cell technologies.