The microstructure of YBa2Cu3O7 films epitaxially grown on step-edge (100) SrTiO3 substrates has been characterized by means of high resolution transmission electron microscopy. The results indicate a relationship between the microstructure of the film acreoss a step and the angle step makes with the substrate plane. On a steep, high-angle step, the film grows with its c-axis perpendicular to that of the film on the substrate surface so that two grain boundaries are formed. On a low-angle step, the film grows without any change in c-axis orientation across the step and without grain boundaries. Epitaxial second phases intergrowths across the steps have been found in some cases which may act as barrier layers when they cut through th YBa2Cu3O7 film.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering