This study investigates the properties of fluorinated silicon dioxide films using hydrosilicofluoric acid and ammonium hydroxide aqua as sources by the temperature-difference-based liquid-phase deposition method. According to the experimental results, the deposition rate and refractive index increase with the concentration of ammonium hydroxide aqua. The secondary ion mass spectrometry depth profile shows that the fluorine concentration is high and uniform throughout the deposited film. The nitrogen is accumulated at the interface. The flatband voltage and leakage current density are functions of the concentration of ammonium hydroxide aqua. (C) 2003 The Electrochemical Society.