TRANSPARENT CONDUCTING ZnO FILMS DEPOSITED BY REACTIVE DC MAGNETRON SPUTTERING FROM METALLIC TARGET Zn

Abstract

Transparent conducting ZnO films are prepared on glass substrates by reactive de magnetron sputtering from metallic target Zn in an Ar – O2 mixture gases. During deposition, the sputtering power was controlled at P = 120W, the total pressure was maintained at p = 2.10-3 torr, the deposition time t = 90 minutes. The substrate was not intentionally heated and no bias was applied. Transmission T%, band gap Eg, refraction index n and extinction coefficient k can be obtained from Swanepoel method. The structure properties of ZnO films were determined from XRD and the films resistivity was measured by a four – point probe method. When the gas ratio of O2/Ar is 1%, the best films resistivity is 1.3x10-3 cm and the average transmission of the films is 86% in the wavelength range of the visible spectrum. The c-axis of all films is highly oriented perpendicular to the plane of substrate.