Domain Formation in Ferroelectric BaTiO₃ Studied by X-Ray Topography. I

Abstract

Three dimensional structure of antiparallel ferroelectric domains formed in c -plates of BaTiO 3 , partly covered with electrodes, has been studied by X-ray topography. Outside the electrodes, clusters of needle-like domains of about (10 µm) 2 in cross section due to the leakage field were observed. These clusters were nucleated from the surface with the negative electrode and almost all of the needle-like domains have terminated inside the crystal near the opposite surface with positive electrode. At the domain boundaries of large domains and at the walls of these needle-like domains, the crystal lattice is strained with the strain field parallel to the c -axis. Under an optical microscope domains are visible with very poor contrast due to the reflexion of light at the domain walls.