Thickness Effect on the Optical Band Gap of V2O5 Thin Films Deposited by Thermal Evaporation

Abstract

Thin V2O5 films have been used as a passive electrode to be applied in some electrochromic devices that requires particular optical, crystallographic and electrochemical energy properties. These properties are greatly influenced by the film thickness. In this work were determined the thickness dependence on, spectral optical absorption and particle size of the V2O5 thin films deposited by thermal evaporation in three nanoscale thickness. It is clear from the results that these particles size apparently are not influenced by the thickness of the film in its formation. Thus, it was verified that the microstructure, mainly the thickness, strongly influences the optical properties, especially the absorption energy, of these samples. The optical gap energy decrease as the film thickness increased. This actually proves that film thickness can be used as a way to modulate the materials optical absorption in optical and optoelectronic devices.

Keywords

• band gap
• vanadium oxide
• thermal evaporation
• thin films