In this study, the influence of oxygen on high rate (up to 110nm m/min) sputtered aluminum doped zinc oxide films (ZnO:Al) was systematically investigated. Different oxygen gas flows from 0 sccm to 8 sccm were inputted into the chamber during the preparation of ZnO: Al films from dual rotatable ceramic targets under high discharge power (14 kW). The resistivity increases from 4.2x10(-4) Omega cm to 4.3x10(-2) Omega cm with the rising oxygen gas flow. While both the carrier concentration and mobility drop by one order of magnitude from 3.4x10(20) cm(-3) to 2.5x10(19) cm(-3) and from 43.5cm(2)/V s to 5.6cm(2)/V s, respectively. The as-grown ZnO:Al films and after-etched ZnO: Al films after a chemical wet etching step in diluted HCl solution (0.5%) exhibit different surface structures. All films show high light transmission and low light absorption but different light scattering properties (diffusion and haze) because of different surface structures. Moreover, ZnO: Al films display different optical bandgaps between 3.51 eV and 3.27 eV, which are corresponding to different carrier concentrations. The variation of mobility and morphology is related with chemisorption of oxygen in the grain boundaries as well as high energetic oxygen ions bombardment. (C) 2010 Elsevier B. V. All rights reserved.