Epitaxial BaTiO3 thin films on MgO

The epitaxy of thin films of BaTiO3 is motivated by the potential integration of electrooptical functions onto silicon. An epitaxial buffer layer of MgO on Si will be needed for optical waveguide formation and for enabling the growth of BaTiO3. In a first step, epitaxial waveguide structures of c-axis oriented BaTiO3 thin films on MgO (001) have been grown by pulsed laser deposition (PLD). The structural properties of the samples have been characterized by Rutherford backscattering spectrometry/ion channeling (RBS/C) and X-Ray diffraction (XRD). We found excellent crystalline quality even up to a thickness of a few microns. Waveguide losses of 2.9 dB cm−1 have been demonstrated.