Chemical Vapor Deposition of ZrO₂ Thin Films Using Zr(NEt₂)4 as Precursor

Abstract
By using tetrakis(diethylamido) zirconium |Zr(NEt₂)4|. excellent quality ZrO₂ thin films were deposited with high growth rates on alumina and glass substrates by chemical vapor deposition. The depositions were carried out in a hot wall reactor at reduced pressure (200 Pa) in the temperature range 500-580°C and in the presence of oxygen. The as-grown films are colourless. smooth and well-adherent to the substrates. SIMS analysis evidenced pure ZrO₂ with a slight superficial contamination of hydrocarbons and nitrogen. The films have a tapered polycrystalline columnar structure well visible in SEM micrographs. From X-ray diffraction analysis, the monoclinic phase resulted as the major phase together with a small variable amount of tetragonal zirconia. Under 550°C the as-grown films resulted highly textured and were dominated by the (020) orientation. The films were annealed in the range 600-1000°C and the effect of annealing on the texture and on the phase and dimensions of the crystallites have been studied.