A structural investigation of high-quality epitaxial thin films

The (PZT 53/47) and (PZT 20/80) films deposited on substrates by RF magnetron sputtering are single-phase epitaxial films. In order to prevent large thermal stresses being induced in the films during the preparation process, the PZT films were cooled slowly through the Curie temperature. Scanning electron microscopy (SEM) showed that the PZT 53/47 film had a pyramid structure on its surface, whereas the PZT 20/80 film had a smooth surface without any observable features. Transmission electron microscopy (TEM) observations showed similar features: the PZT 53/47 film had a coarse columnar structure, whereas the PZT 20/80 film had a fine crystalline structure; this is due to the better lattice matching in the latter.