Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100W, 1.5 Pa, 60 min, 125 degrees C). The sheet resistance of 510 Omega and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain. (C) 2016 Elsevier B.V. All rights reserved.