Optical Properties of Vanadium Pentoxide Thin Films Prepared by Thermal Evaporation Method (original) (raw)

The Vanadium Pentoxide (V 2 O 5) thin films were obtained using thermal evaporation technique on a glass substrate. Many films of different thickness were prepared. Deposition rate was controlled by using quartz monitor connected with the system and the rate was about 5 nm per second for all films. The transmittance and reflectance of each film, in the spectral range 300 to 900 nm, were measured from which the optical constants (Refractive index, Absorption coefficient, Extinction coefficient, and Energy gap) were determined. The energy gap was calculated for two films (d1=320 nm and d2=700 nm) and found to be 1.87 and 2.1 eV for the direct allowed transitions respectively. All measured values were in consistent with other previous studies. All our films found to have an amorphous structure as was shown by the XRD patterns of the films.