Room-temperature growth of $ZrO2$ thin films using a novel hyperthermal oxygen-atom source

Thin $ZrO2$ films have been grown on Si(100) and on glassy carbon substrates using a novel atomic oxygen source in a standard molecular beam epitaxy system. The oxygen source produces a flux of hyperthermal oxygen atoms with an ion/atom-ratio $≪0.001$ through electron stimulated desorption from a Ag alloy surface at an operating pressure $<10−8$ Torr. The films were grown at room temperature and analyzed using Rutherford backscattering spectroscopy, x-ray diffraction (XRD), x-ray photoelectron spectroscopy and transmission electron microscopy (TEM). The results show the successful growth of fully stoichiometric $ZrO2$ films on nonheated Si(100) and on amorphous glassy carbon substrates at a rate of 0.58 $μ$m/hr. The XRD and TEM investigations indicate the formation of a mixed amorphous/orthorhombic film structure. Based on the film growth rate, the O flux produced by the electron stimulated desorption atom source is estimated to be $8×1014$ $atoms/cm2 s.$ This flux value is consistent with other determinations using ion scattering spectroscopy and pyromellitic dianhydride-oxydianiline polyimide (Kapton^®) erosion experiments.