In this study, WO3 films for electrochromic devices were deposited on a Sn-doped In2O3 substrate by hollow-cathode gas-flow sputtering using a pair of facing W metal targets. The sputtering power for all depositions was fixed at 1000 W (3.9 W/cm(2)). The deposited WO3 films were amorphous in structure. Static deposition rates were achieved to be higher by two orders of magnitude than those for conventional dc magnetron sputtering, as well as to be the comparable colouration efficiency. (C) 2012 Elsevier B.V. All rights reserved.