Determination of optical properties of amorphous Ta2O5 films deposited by spin- and dip-coating methods

Abstract

The optical properties of amorphous Ta2O5 films prepared by the sol-gel dip- and spin-coating deposition technique and dried at 60 degrees C have been investigated. Refractive index, extinction coefficient and optical energy gap have been calculated from optical transmission measurements using the Swanepoel method. The films of similar thickness deposited by the two methods were compared. It is shown that the optical properties are dependent on the deposition methods. The energy band gap of the Ta2O5 films is 3.75 +/- 0.12 eV and is independent of the coating methods.