Unveiling Center‐Type Topological Defects on Rosettes of Lead Zirconate Titanate Associated to Oxygen Vacancies

AbstractMany attempts have been made to reduce degradation properties of Lead Zirconate Titanate (PZT) thin film capacitors. Although each degradation property has been studied extensively for the sake of material improvement, it is desired that they be understood in a unified manner in order to reduce degradation properties simultaneously. This can be achieved if a common source(s) of degradations is identified and controlled. In the past it was noticed that oxygen vacancies play a key role in fatigue, leakage current, and electrical degradation/breakdown of PZT films. It is now known that space charges (oxygen vacancies, mainly) affect ageing, too. Therefore, a quantitative ageing mechanism is proposed based on oxygen vacancy migration under internal field generated by either remanent polarization or spontaneous polarization. Fatigue, leakage current, electrical degradation, and polarization reversal mechanisms are correlated with the ageing mechanism in order to establish guidelines for simultaneous degradation control of PZT thin film capacitors. In addition, the current pitfalls in the ferroelectric test circuit is discussed, which may cause false retention, imprint, and ageing.

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Electromechanical Manipulation of Topological Defects to Yield Giant Piezoelectric Response in Epitaxial Lead Zirconate Titanate Bilayers on Silicon

Advanced Electronic Materials ◽

10.1002/aelm.202100195 ◽

2021 ◽

pp. 2100195

Author(s):

Richard Stephen Winkler ◽

Yangyang Zhang ◽

Qi Zhang ◽

Zhe Wang ◽

Yimei Zhu ◽

...

Keyword(s):

Lead Zirconate Titanate ◽

Topological Defects ◽

Lead Zirconate ◽

Piezoelectric Response ◽

Zirconate Titanate

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First Principles’ Investigation of Electronic Properties of Hf, Ag, Cd, Zn, Ce, Nd, Sm-Modified Lead Zirconate Titanate

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2016.5768 ◽

2016 ◽

Vol 13 (10) ◽

pp. 7661-7665

Author(s):

R. A Hussein ◽

M El-Okr ◽

I. I Bashter ◽

M Ibrahim

Keyword(s):

Electronic Properties ◽

Lead Zirconate Titanate ◽

First Principles ◽

Density Functional ◽

Oxygen Vacancies ◽

Energy State ◽

Fatigue Behavior ◽

Lead Zirconate ◽

Theoretical Explanation ◽

Zirconate Titanate

First principles investigations, including density functional theory (DFT) have been applied to calculate the electronic properties of A-site modified lead zirconate titanate (PZT). The theoretical explanation for the origin of fatigue in ferroelectric perovskite oxides was implemented to study the fatigue behavior. The explanation indicates that, the fatigue is related to the weakness of π bond between Ti 3d and O 2p states, caused by the occupancy of the Ti 3d state by electrons which released from oxygen vacancies. If a certain energy state of the additive element founded to be overlapped with the Ti 3d state at conduction band minima, then it will sharing the electrons released by oxygen vacancies with the Ti 3d state. Therefore, when the Ti 3d state become less occupied with electrons the π bond between the Ti 3d and O 2p states become more maintained and the composition is less susceptible to fatigue.

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Donor–Doped Lead Zirconate Titanate (PbZr1−xTixO3) Films

MRS Proceedings ◽

10.1557/proc-335-53 ◽

1993 ◽

Vol 335 ◽

Cited By ~ 2

Author(s):

Seshu B. Desu ◽

Dilip P. Vijay ◽

In K. Yoo

Keyword(s):

Lead Zirconate Titanate ◽

Oxygen Vacancies ◽

Lead Zirconate ◽

Ferroelectric Films ◽

Leakage Currents ◽

Low Leakage ◽

Zirconate Titanate ◽

Switchable Polarization

AbstractProperties of undoped– and doped–ferroelectric PbZr1−xTixO3. films, with both Pt or RuO2 electrodes, were compared, with a view to understand the reasons for degradation of ferroelectric films. Donor–doped (e.g., Nb5+ at Ti4+ site) PbZr1−xTixO3 films, for which the PbO loss has been compensated, showed higher resistance to fatigue and low leakage currents compared to those of undoped films. The fatigue of ferroelectric films, a decrease in switchable polarization with increasing number of polarization reversals, has been attributed to the migration of oxygen vacancies and their entrapment at various interfaces (e.g., electrode/ferroelectric interface) that are present in the film.

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Convergent-bceam diffraction studies on lead zirconate titanate Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143961 ◽

1986 ◽

Vol 44 ◽

pp. 482-483

Author(s):

M.L.A. Dass ◽

T.A. Bielicki ◽

G. Thomas ◽

T. Yamamoto ◽

K. Okazaki

Keyword(s):

Lead Zirconate Titanate ◽

Direct Proof ◽

Lead Zirconate ◽

Subsolidus Phase ◽

Pzt Ceramics ◽

Subsolidus Phase Diagram ◽

Zirconate Titanate ◽

Two Phases ◽

Cbd Method ◽

Titanate Ceramics

Lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), ceramics are ferroelectrics formed as solid solutions between ferroelectric PbTiO3 and ant iferroelectric PbZrO3. The subsolidus phase diagram is shown in figure 1. PZT transforms between the Ti-rich tetragonal (T) and the Zr-rich rhombohedral (R) phases at a composition which is nearly independent of temperature. This phenomenon is called morphotropism, and the boundary between the two phases is known as the morphotropic phase boundary (MPB). The excellent piezoelectric and dielectric properties occurring at this composition are believed to.be due to the coexistence of T and R phases, which results in easy poling (i.e. orientation of individual grain polarizations in the direction of an applied electric field). However, there is little direct proof of the coexistence of the two phases at the MPB, possibly because of the difficulty of distinguishing between them. In this investigation a CBD method was found which would successfully differentiate between the phases, and this was applied to confirm the coexistence of the two phases.

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