A spectroscopic ellipsometry investigation of RF-sputtered crystalline vanadium pentoxide thin films

Vanadium pentoxide (V2O5) raised much interest, in several fields, specially relating to thin film lithium microbatteries Yet, literature mentioned different results a electrochemical performance of these film with thickness. The present work is focused on the use of spectroscopic ellipsometry on V2O5 crystalline thin film during growth. Optical properties were determined in the near-IR-visible range (0.25-2 mu m). Effective media approximation base model was developed and was used to determine the optical constants of thin films. Thickness and roughness obtained corresponded well to respectively SEM and AFM results: Based on optical refractive index evolution, a density gradient was' identified through the film thickness: These results could explain in parts the thickness influence on the electrochemical performance of V2O5 thin films.