Composition and microstructure of zirconia films obtained by MOCVD with a new, liquid, mixed acetylacetonato-alcoholato precursor

The new mixed alcoholato-acetylacetonato precursor Zr(acac)(2)(hfip)(2), wh ere hfip = OCH(CF3)(2), has been used to deposit zirconia at temperatures b etween 350 and 700 degrees C. This compound. a liquid at room temperature, combines a high vapor pressure with a relatively low hydrolysis sensitivity . At 0.5 mbar total pressure, high growth rates of up to 200 nm min(-1) wer e reached in our cold-wall reactor, the apparent activation energy in the k inetic regime being 81.5 kJ mol(-1). Zirconia films with C and F levels bet ween 0.25 and 0.50 at.-% were obtained in a temperature window of 475 degre es C to 625 degrees C. The impact of deposition temperature on the microstr ucture has been followed by both field-emission scanning electron microscop y (SEM) and X-ray diffraction (XRD). With increasing deposition temperature . the initially cubic zirconia films convert progressively into the monocli nic equilibrium phase, probably due to a crystallite size effect.