STRUCTURAL AND ELECTRICAL-PROPERTIES OF ANTIFERROELECTRIC LEAD ZIRCONATE THIN-FILMS PREPARED BY REACTIVE MAGNETRON COSPUTTERING

The structural and electrical properties of antiferroelectric lead zir conate thin films were investigated. The films were prepared by a reac tive magnetron co-sputtering method followed by rapid thermal annealin g. The crystallized films showed (240) preferred orientation on platin um-coated silicon substrates. The lead content in the films was found to affect the crystallization temperatures, the preferred orientation, the film morphology and the electrical properties. In particular, the hysteresis behaviour is sensitive to the amount of lead. The electric field forced transformation from the antiferroelectric phase to the f erroelectric phase was very similar to that observed in single crystal s at room temperature, with a maximum polarization value of 70 mu Ccm( -2). The average field required to excite the ferroelectric state and that for reversion to the antiferroelectric state were 290 kV cm(-1) a nd 180 kV cm(-1) respectively. The dielectric constant was 200 with an associated loss of 0.05 at 1 MHz. The Curie temperature was 248 degre es C at 1 kHz. The conduction mechanism of the films was similar to th at observed for lead zirconate titanate films.