Optimization of the Fabrication Parameters of PZT 52/48 Thin Films by Pulsed Laser Ablation
Thin films of PbZr0,52Ti0,48O3 (PZT) for applications in piezoelectric actuators were deposited by the pulsed laser deposition technique (PLD) over Pt/Ti/SiO2/Si substrates. The effect of different electrode and PZT deposition and processing conditions on the ferroelectric and piezoelectric properties of the devices was investigated. X-Ray diffraction results showed that the deposition temperature for the electrodes had a strong influence on the PZT orientation; the increase in the electrode deposition temperature changes the PZT orientation from random or (111) to (001) depending also on PZT deposition pressure. From scanning electron microscope (SEM) pictures one could also observe that the deposition pressure affects the porosity of the PZT films, which increases with the pressure above 1×10-1 mbar for films deposited at room temperature. The measurement of the ferroelectric hysteresis curves confirmed that the structural changes induced by different processing parameters affected the ferroelectric properties of the material. The best ferroelectric properties including fatigue endurance were obtained for electrodes made at high temperature and for PZT deposited at 2×10-2 mbar and heat treated at 675°C for 30 minutes in an oxygen atmosphere. The piezoelectric coefficient d33, measured using a Michelson interferometer, had values in the range between 20 and 60 pm/V, and showed a strong dependence on the thickness of the PZT films.
Paula Maria Vilarinho
J. R. A. Fernandes, E. Joanni, R. Savu, "Optimization of the Fabrication Parameters of PZT 52/48 Thin Films by Pulsed Laser Ablation", Materials Science Forum, Vols. 514-516, pp. 1353-1357, 2006