The deposition of thin silicon dioxide films using plasma enhanced and ozone assisted thermal chemical vapor deposition techniques and tetraethylorthosilicate (TEOS) as precursor in AME Precision 5000 reactor has been carried out. The properties of the oxide, such as etch rate, hydrogen concentration, dielectric constant, andC–Vbehavior, were investigated as a function of the deposition parameters, such as radio‐frequency (rf) power, gas composition, and temperature, and post rapid thermal annealing (RTA). The paper reports these results and discusses the findings. The electrical properties of these oxides, plasma, and ozone, were influenced primarily by water vapor that was absorbed and trapped into the bulk of the film either during or within a short time of deposition. The film quality can be considerably improved by RTA between 800 and 1000 °C.