Surface Energy Anisotropy of SrTiO3 at 1400 C in Air

Published

October 12, 2021

Author(s)

T Sano, D M. Saylor, G S. Rohrer

Abstract

Geometric and crystallographic measurements of grain boundary thermal grooves and surface faceting behavior as a function of orientation have been used to determine the surface energy anisotropy of SrTiO₃ at 1400 C in air. Under these conditions, thermal grooves are formed by surface diffusion. The surface energy anisotropy was determined using the capillarity vector reconstruction method under the assumption that Herring's local equilibrium condition holds at the groove root. The results indicate that the (100) surface has the minimum energy. For surfaces inclined between 0 and 30 from (100), the energy increases with the inclination angle. Orientations inclined by more than 30 from (100) are all about 10 % higher in energy and, within experimental uncertainty, energetically equivalent. A procedure for estimating the uncertainties in the reconstructed energies is also introduced. Taken together, the orientation dependence of surface facet formation and the measured energy anisotropy lead to the conclusion that the equilibrium crystal shape is dominated by 100}, but also includes 100} and 111} facets. Complex planes within about 15 of 110) are also part of the equilibrium shape.

Citation

American Ceramic Society Bulletin

Pub Type

Journals

Keywords

atomic force microscopy (AFM), electron back-scatter diffraction (EBSD), strontium titanate, surface energy, surface faceting, thermal groove, Wulff shape

Citation

Sano, T. , Saylor, D. and Rohrer, G. (2021), Surface Energy Anisotropy of SrTiO₃ at 1400 C in Air, American Ceramic Society Bulletin (Accessed January 2, 2025)