Electrical properties of PZT thin films on Al-Ti electrodes

Pb(Zr/sub 0.53/Ti/sub 0.47/)O/sub 3/ thin films, with the morphotropic phase boundary (MPB) composition, were successfully grown on [111] silicon substrates by a high oxygen pressure RF sputtering technique, which is used for the preparation of HTS thin films. Underlayers of Ti and Al were evaporated on the [111] oxidized Si wafers and then subjected to an annealing process before the ferroelectric thin film was deposited. The best structural characteristics were found for the annealing temperature of 600/spl deg/C and a deposition temperature of 450/spl deg/C. For these conditions a perovskite structure with [011] and [110] preferential orientations was obtained. The films show a peak in the dielectric constant at 380/spl deg/C, near the Curie temperature for PZT in the MPB composition, and a slim hysteresis loop with Pr /spl ap/ 2 /spl mu/C/cm/sup 2/ and Ec /spl ap/ 25 kV/cm at 3V.