Crystallization in Pb(Zr, Ti)O3/Pt Thin Films on Mg2TiO4 Buffer Layer

Pb(Zr, Ti)O3 (PZT)/Pt structures were fabricated on an Si substrate with a Mg2TiO4 buffer layer and their crystallographic and morphological properties were studied. PZT and Mg2TiO4 thin films were deposited by the ultrasonic spraying metal-organic chemical vapor deposition (MOCVD) at atmospheric pressure. Pt thin films were deposited by RF magnetron sputtering. The crystallographic properties of Pt films were affected by the structure of the Mg2TiO4 films on which they grow. (111)-oriented platinum films were deposited on (111) Mg2TiO4 independently of deposition conditions. However, the Pt films deposited on (100)-oriented Mg2TiO4 films show a mixed orientation of (111) and (100), and the degree of (100) orientation was a function of the deposition temperature and crystallinity of Mg2TiO4 films. The surface morphology of Pt films differs depending on their crystallographic properties. (111)-oriented Pt films have excellently flat and dense surface morphology. (111)- or (100)-oriented PZT thin films were deposited on (111)- or (100)-oriented Pt layers, respectively. The surface morphology of (111)-oriented PZT thin films was more dense and flat than that of (100)-oriented PZT films.