EPITAXIAL GROWTH OF SrRuO3 THIN FILM ELECTRODE ON Si BY PULSED LASER DEPOSITION

Pseudocubic SrRuO3 (100) epitaxial thin films were fabricated on Si (100) with a SrO buffer layer by PLD. RHEED revealed that the SrO layer is epitaxially grown on naturally oxidized Si substrates with an orientation relationship of SrO (110)/Si (100) and SrO < 001 > //Si < 011 > . Subsequent SrRuO3 deposition resulted in a (100) epitaxial thin film possessing good crystallinity with a FWHM of 1.9 degrees in the SrRuO3 (200) rocking curve by XRD. Based on the Gibbs free energy change in the reaction of Si with alkaline earth metal oxides, deoxidization of SiO2 on Si by Sr is thought to play an important role in the epitaxial growth of SrO. Cross-sectional observation for the optimized SrRuO3/SrO/Si sample using TEM revealed that the thickness of the SrO layer is < 2 nm and that the SrRuO3 electrode forms an epitaxial thin film almost directly on Si. 27 refs.