INFLUENCE OF SPUTTERING POWER ON PHYSICAL PROPERTIES OF NANOSTRUCTURED ZINC ALUMINUM OXIDE THIN FILMS FOR PHOTOVOLTAIC APPLICATIONS

In the present work Zinc Aluminum Oxide (ZAO) thin films have been deposited on glass substrates by DC reactive magnetron sputtering technique at different sputtering powers of Zn varied from 85 W - 125 W. XRD patterns exhibits ZAO thin films had a diffraction peak corresponding to (0 0 2) preferred orientation with c-axis perpendicular to the substrate surface. The preferred orientation is due to the lowest surface free energy for (0 0 2) plane. The minimum resistivity of 1.67 X 10(-4) Omega. cm is found for the thin film deposited at sputtering power of 115 W. Optical absorption edge of nanostructured ZAO thin films has a significant blue shift to the region of higher photon energy. Such a shift is attributed to the Burstein-Moss effect. The optical band gap of nanostructured ZAO thin films is found to be in the range of 3.43 - 3.60 eV. The carrier concentration of ZAO thin films is found to be in the range of 3.95 X 10(20) cm(-3) - 1.38 X 10(21) cm(-3).