The room-temperature epitaxial growth of CeO2 films on Si(111) substrates was examined in situ by combined use of a coaxial impact-collision ion scattering spectroscopy (CAICISS) and the laser molecular beam epitaxy (laser MBE). It was found that the crystal quality of CeO2 ultrathin films (∼3 nm thick) as-grown in UHV ( ∼ 10-9 Torr) could be improved remarkably by a few minutes of O2 gas exposure (∼10-5 Torr) at room temperature. A three-fold symmetry in the Ce signal intensity of azimuth rotational CAICISS spectra, which exhibited the type-B epitaxial growth (CeO2∥S1), was observed for the films thicker than about 1 nm.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)