Determination of Thickness and Optical Constants of ZnO Thin Films Prepared by Filtered Cathode Vacuum Arc Deposition

ZnO thin films are prepared on glass substrates by filtered cathode vacuum arc (FCVA) deposition technique. A new method is demonstrated to extract the refractive index, thickness and optical band gap of ZnO thin films from the transmission spectrum alone. The refractive index is calculated from the extremes of the interference fingers. The transmission spectrum is divided into two terms, non-interference term and interference effect term. The thickness of thin films is calculated by simulating the interference term, and the non-interference term is used to calculate optical band gap with the gained thickness. The results are compared with measurements by using an ellipsometry and a scanning electron microscope.