Fatigue properties of oriented PZT ferroelectric thin films

Oriented PZT thin films with Zr/Ti ratio of 60/40 were prepared using a multi-target R.F. sputtering system. The films were (1 0 0) or (1 1 1) oriented when grown on Pt/TiO2/SiO2/Si and exhibited c-axis epitaxial microstructure when deposited on Pt/MgO. Electrical measurements were performed in order to investigate the fatigue properties of the films. Fatigue characteristics of the Pt/PZT/Pt capacitors were found to be strongly dependent on their crystalline orientation: (1 1 1) and (0 0 1) oriented films exhibited poor fatigue endurance unlike (1 0 0) oriented films that did not fatigue. Lastly, almost full recovery of polarisation was obtained for c-axis epitaxial films while (1 1 1) oriented films showed only partial restoration.