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An r.f. reactive sputter deposition technique was adopted to deposit ferroelectric lead zirconate titanate (PZT) thin films with high rate from a ZrTi alloy target combined with PbO pellets. The deposition characteristics, including the effects of the PbO area ratio, were discussed. A new deposition mode called the `quasi-metallic mode' was observed. Perovskite PZT films were prepared at a growth temperature as low as 450°C. However, because the target structure is unstable, we proposed a mixture target which consisted of Zr, Ti and PbO. Fundamental experiments were researched using the powder target. The perovskite PZT film could also be obtained at 450°C with better electrical properties.

An rf reactive sputter deposition technique was adopted to deposit lead zirconate titanate (PZT) thin films from a ZrTi (50%/50%) alloy target combined with PbO pellets. A new deposition mode called the quasi-metallic mode was observed. Crystalline structure and Pb/(Zr + Ti) atomic ratio of the films prepared in the mode were investigated as functions of growth temperature and PbO area ratio. Perovskite PZT films were obtained at a growth temperature as low as 450°C. Lattice constants, depth profiles, ferroelectric, dielectric characteristics of the films prepared from the (ZrTi + 30% PbO) target were investigated. The perovskite films prepared at 450°C exhibit the remanent polarization of 20μC/cm2, the coercive field of 150 kV/cm, the dielectric constant as high as 561, and leakage current smaller than 10−6/cm2 at the electric field lower than 235 kV/cm.

Ferroelectric lead zirconate titanate (PZT) thin films were prepared on Pt/Ti/SiO2/Si substrates from a ZrTi (50%/50%) alloy target combined with PbO pellets using an rf reactive sputter deposition technique. Perovskite PZT films were obtained at a growth temperature as low as 450°C in the quasi-metallic mode. Crystalline structure, depth profiles, ferroelectric and dielectric characteristics of the films prepared from the (ZrTi+30%PbO) target were investigated. The interdiffusion between the PZT film and the Pt/Ti/SiO2/Si substrate was suppressed by the low-temperature sputtering. The remanent polarization, leakage current and dielectric constant decrease with increasing growth temperature. The perovskite films prepared at 450°C exhibit the remanent polarization of 20 µC/cm2, the coercive field of 150 kV/cm, the leakage current smaller than 10-6 A/cm2 at the electric field lower than 235 kV/cm, and the dielectric constant as high as 561.

An rf reactive sputter deposition technique was adopted to deposit ferroelectric lead zirconate titanate (PZT) thin films from a ZrTi (50%/50%) alloy target combined with PbO pellets. Deposition characteristics including the effects of PbO area ratio were discussed. A new deposition mode called the near-metallic mode was observed. The crystallinity and the composition of the films prepared in the near-metallic mode were investigated as functions of PbO area ratio and substrate temperature. Excess Pb supply tended to enhance perovskite phase formation. Near-stoichiometric perovskite PZT films were obtained at a substrate temperature as low as 450° C. On the other hand, for a PZT+PbO target, perovskite PZT films were obtained only at temperatures higher than 540° C. Deposition rate of perovskite films from the ZrTi+PbO target was 2–3 times higher than that from the PZT+PbO target.

Pb(Zr,Ti)O3 (PZT) films were grown on fused quartz substrates by reactive sputtering using a Zr/Ti (50%/50%) alloy target combined with PbO pellets under argon pressure of 10mTorr and O2/Ar flow rate ratio of 2.1%. Structure and deposition rate of the films have been investigated as functions of substrate temperature and PbO content. When films were grown in near metallic mode using a Zr/Ti + 41%PbO target, perovskite PZT films were successfully prepared at a temperature as low as 450°C, and in the wide range from 450°C to 570°C. It was impossible to obtain perovskite PZT films using only a stoichiometic Pb(Zr0.5Ti0.5)O3 ceramic target, while perovskite PZT films could be obtained between 540°C and 570°C using a Pb(Zr0.5Ti0.5)O3 + 15%PbO target. Deposition rate of perovskite films for the Zr/Ti + 41%PbO target was 2–3 times higher than that for the PZT + 15%PbO target.