Influence of MgO substrate miscut on domain structure of pulsed laser deposited $SrxBa1−xNb2O6$ as characterized by x-ray diffraction and spectroscopic ellipsometry

Pulsed laser deposition has been used to grow highly oriented $SrxBa1−xNb2O6$ $(SBN:x)$ on (001)MgO and miscut MgO $(2°$ off 001 toward 100) in the presence of a pulsed $O2$ jet. The target stoichiometry was $SBN:52±1.5%,$ but films grown at $700 °C$ were cation deficient and had a final composition of $SBN:61±1.5%.$ Visually, the films were specular, but spectroscopic ellipsometry measurements showed they were highly absorbing, requiring a short anneal in $O2$ at $700 °C$ to make them fully transparent. Pole figure analysis indicated that a thick $626±1 nm$ film consisted of the characteristic antiphase domain structure of SBN, but four antiphase domains were found in a thin $185±1 nm$ film. However, the formation of these additional domains was suppressed in a $165±1 nm$ film grown on miscut MgO. Spectroscopic ellipsometry measurements have been made to measure surface and interface roughness, film thickness, as well as the spectroscopic refractive index and extinction coefficient of the films.