Influence of RF Power on the Physical Properties of ZnTe Thin Films

Abstract

In this study, zinc telluride (ZnTe) thin films were deposited using radio frequency (RF) sputtering at various powers ranging from 100 to 250 W for 60 minutes. Structural and optical properties were investigated as a function of RF power. X-ray diffraction (XRD) analysis revealed that increasing the RF power led to a growth in the crystallite size from 3 to 9.4 nm, while dislocation density and microstrain decreased. The ZnTe films exhibited a cubic crystal structure with a lattice parameter of 6.08 Å. Scanning Electron Microscopy (SEM) showed that the film surfaces are uniform and free of cracks. Optical measurements using UV-Vis-NIR spectrophotometry indicated that both transmittance and optical band gap increased from 1.82 to 1.94 eV with increasing RF power. The modulation of the optical and structural properties of ZnTe thin films by RF power, as demonstrated in this study, opens perspectives for optimizing these materials in real device architectures, particularly for more efficient solar cells or high-performance sensors.