Influence of oxygen partial pressure on the composition and orientation of strontium-doped lead zirconate titanate thin films

The lead zirconate titanate (PZT) thin film was deposited on platinized silicon wafer substrate by the rf magnetron sputtering method. In order to investigate the effect of cooling ambient, oxygen partial pressure was controlled during cooling PZT films. The PZT films cooled at lower oxygen partial pressure had perovskite phase and pyrochlore phase in both as-grown and postannealed films, but in the PZT films cooled at higher oxygen partial pressure, pyrochlore phases were not detected by XRD. As the oxygen partial pressure became lower during cooling, the capacitors had low values of remanent polarization and coercive field for as-grown films. The PZT capacitor with such a low value was recovered by postannealing in air, but its electrical properties had the same tendency before and after annealing. Microstructure was also affected by cooling ambient. Higher oxygen partial pressure on cooling reduced the number of very fine grains, and enhanced uniform grain distribution. Fatigue characteristics were also enhanced by cooling at higher oxygen partial pressure. However, the imprint was negligible irrespective of oxygen partial pressure upon cooling. The cooling procedure at higher oxygen ambients is believed to reduce the amounts of nonferroelectric second phases and oxygen vacancies. We find that oxygen partial pressure during cooling is a considerable process parameter. Therefore, care should be taken in treating the parameter after depositing films.

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Failure Mechanisms of Lead Zirconate Titanate Thin Films during Electromechanical Loading

2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF) ◽

10.1109/ifcs-isaf41089.2020.9234833 ◽

2020 ◽

Author(s):

Kathleen Coleman ◽

Julian Walker ◽

Wanlin Zhu ◽

Song Won Ko ◽

Peter Mardilovich ◽

...

Keyword(s):

Thin Films ◽

Lead Zirconate Titanate ◽

Failure Mechanisms ◽

Lead Zirconate ◽

Zirconate Titanate ◽

Electromechanical Loading

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Characteristics of Sputtered Lead Zirconate Titanate Thin Films with Different Layer Configurations and Large Thickness

IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control ◽

10.1109/tuffc.2020.3039230 ◽

2020 ◽

pp. 1-1

Author(s):

Kensuke Kanda ◽

Tsukasa Koyama ◽

Takeshi Yoshimura ◽

Shinichi Murakami ◽

Kazusuke Maenaka

Keyword(s):

Thin Films ◽

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Large Thickness ◽

Zirconate Titanate

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Improvement of Ferroelectric Properties of Lead Zirconate Titanate Thin Films by Ion-substitution using Rare-earth Cations

MRS Proceedings ◽

10.1557/proc-830-d3.3 ◽

2004 ◽

Vol 830 ◽

Author(s):

Hiroshi Nakaki ◽

Hiroshi Uchida ◽

Shoji Okamoto ◽

Shintaro Yokoyama ◽

Hiroshi Funakubo ◽

...

Keyword(s):

Thin Films ◽

Rare Earth ◽

Lead Zirconate Titanate ◽

Ferroelectric Property ◽

Ferroelectric Properties ◽

Lead Zirconate ◽

Crystal Anisotropy ◽

Pzt Film ◽

Zirconate Titanate ◽

Ion Substitution

ABSTRACTRare-earth-substituted tetragonal lead zirconate titanate thin films were synthesized for improving the ferroelectric property of conventional lead zirconate titanate. Thin films of Pb1.00REx (Zr0.40Ti0.60)1-(3x /4)O3 (x = 0.02, RE = Y, Dy, Er and Yb) were deposited on (111)Pt/Ti/SiO2/(100)Si substrates by a chemical solution deposition (CSD). B-site substitution using rare-earth cations described above enhanced the crystal anisotropy, i.e., ratio of PZT lattice parameters c/a. Remanent polarization (Pr) of PZT film was enhanced by Y3+-, Dy3+- and Er3+-substitution from 20 μC/cm2 up to 26, 25 and 26 μC/cm2 respectively, while ion substitution using Yb3+ degraded the Pr value down to 16 μC/cm2. These films had similar coercive fields (Ec) of around 100 kV/cm. Improving the ferroelectric property of PZT film by rare-earth-substitution would be ascribed to the enhancement of the crystal anisotropy. We concluded that ion substitution using some rare-earth cations, such as Y3+, Dy3+ or Er3+, is one of promising technique for improving the ferroelectric property of PZT film.

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