Crack-free polycrystalline BaTiO3 films of up to 1-µm thickness were grown on silicon and on silicon-on-sapphire (SoS) substrates by pulsed laser deposition. The quality of films of different thickness was studied, particularly the onset of the formation of cracks. The crystallinity of the films was confirmed by x-ray diffraction measurements. The thickness and composition of the films were examined by Rutherford backscattering spectrometry. The optical properties (index of refraction and damping) of planar BaTiO3 waveguides were determined with a prism coupling setup. The films showed an optical attenuation of less than 2 dB/cm and a birefringence of up to 0.01.
© 2005 Optical Society of America
Thomas Lipinsky, Juergen Schubert, and Christoph Buchal, "Crack-free BaTiO3 films on Si with SiO2, MgO, or Al2O3 buffer layers," J. Opt. Soc. Am. B 22, 913-916 (2005)