Epitaxial LiTaO3 thin film by pulsed metalorganic chemical vapor deposition from a single precursor

Epitaxial LiTaO3 thin films were grown on (0001) sapphire in a low pressure chemical vapor deposition reactor of a new design, using lithium tantalum hexa-t-butoxide as the precursor. X-ray diffraction shows that the LiTaO3 c axis is normal to the sapphire surface. The x-ray pole figure and cross-section transmission electron microscopy diffraction show that the films were also in-plane oriented, with sapphire [101̄0] parallel to lithium tantalate [101̄0]. The refractive index of the film compares well with bulk values, over a wide wavelength range.