This investigation reports surface chemistry and nanoscale characterizations of BiFeO3 (BFO) thin films prepared by radio-frequency magnetron sputtering. The films were grown successfully at temperatures as low as 350 S C and possessed a pure perovskite phase. The crystal structure, microstructure, and surface chemistry of the BFO films changed significantly with the working pressure. The X-ray photoelectron spectrometry and Auger electron spectroscopy results indicate that the metallic bismuth and Bi2O3 second-phase particles of the BFO films occurred at low and high working pressure condition, respectively. The domain structure imaging and piezoelectric property of the BFO film grown at 20 mTorr was obtained by piezoresponce force microscopy. (c) 2005 The Electrochemical Society.