Dielectric Behavior of YMnO3 Epitaxial Thin Film at around Magnetic Phase Transition Temperature

Relationship between magnetic ordering and ferroelectric polarization switching in YMnO3 epitaxial thin film was investigated. It was found that Néel point of the YMnO3 film is below 80 K, which is consistent with that of YMnO3 single crystal by neutron diffraction. From temperature dependence of the polarization-electric field hysteresis loops and the dielectric permittivity-voltage characteristics, ferroelectric polarization switching behavior was investigated from 300 to 10 K in detail. The ferroelectric polarization switching behavior accords with Ishibashi-Orihara’s theory. Moreover, it was found that the dielectric permittivity under bias electric field have a anomaly below 80 K and the nucleation density for the ferroelectric polarization switching decreases below 130 K, which is higher than 80K.

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Dielectric behavior of alumina thin film under high DC electric field prepared by sol–gel method

Journal of Advanced Dielectrics ◽

10.1142/s2010135x13500173 ◽

2013 ◽

Vol 03 (03) ◽

pp. 1350017 ◽

Cited By ~ 10

Author(s):

Manwen Yao ◽

Wei Shan

Keyword(s):

Thin Film ◽

Electric Field ◽

Aluminum Oxide ◽

Breakdown Strength ◽

Amorphous State ◽

Dielectric Behavior ◽

Large Area ◽

Sem Images ◽

Dc Electric Field ◽

Electrode Edge

Dielectric behavior of aluminum oxide (Al2O3) thin film under high DC electric field is presented and discussed. Aluminum oxide thin films were prepared starting from aluminum isopropoxide as a precursor via a wet chemistry route. Silicon substrates and silica glass substrates were used to deposit the films via spin-coating technique. The deposited films were then annealed under 450°C–700°C for 2–3 h. Dense, crack-free and uniform films were obtained. The thickness of the films is in the range of 200–800 nm. The films obtained are in amorphous state as revealed by the X-ray diffraction patterns. Voltage–Current (V–I) characteristics of the films were used to study the dielectric behavior of the films. Very low leakage current density J under high DC electric field E can be obtained. The breakdown electric field of the films is around 1.2 MV/cm. The V–I characteristics of the films are slightly nonlinear. With platinum as bottom electrode and gold as top electrode, successive breakdown phenomena of the films under high DC electric field were observed. Each breakdown event of the film corresponds to a sharp spike at the V–I plot of the sample. The shape of the breakdown spots of the films are in crater-like with a breakdown channel of diameter around a few micrometers as revealed by SEM images. The top gold electrode at the breakdown spots either splashed out or ripped off from the breakdown spots, which isolated the breakdown spots from rest of the electrode, and made the successive breakdown of the sample possible. The breakdown spots of the sample are concentrated at the edge of the electrode with proportional spacing, which can be easily understood as the edge effect of the parallel capacitor configuration, while the uniform distribution of the breakdown spots signifies that the uniformity of the films thus prepared are satisfied. Breakdown spots apart from the electrode edge can also be observed. Most of such spots associated with ripped-off gold film electrode in large area. We suppose such breakdown took place at higher electric field after the successive breakdown at the electrode edge and the isolation of the edge part from rest of the sample. Higher energy is needed to tear off larger section of the electrode. The breakdown characteristics of the films reported in this work are useful for the further study to enhance the breakdown strength of the film.

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Reliable polarization switching of BiFeO 3

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2012.0197 ◽

2012 ◽

Vol 370 (1977) ◽

pp. 4872-4889 ◽

Cited By ~ 24

Author(s):

S. H. Baek ◽

C. B. Eom

Keyword(s):

Electric Field ◽

Room Temperature ◽

Remanent Polarization ◽

Magnetic Ordering ◽

Polarization Switching ◽

Ferroelectric Materials ◽

Promising Candidate ◽

Switching Path ◽

Ferroelectric Memory ◽

Rhombohedral Symmetry

As a room temperature multi-ferroic with coexisting anti-ferromagnetic, ferroelectric and ferroelastic orders, BiFeO 3 has been extensively studied to realize magnetoelectric devices that enable manipulation of magnetic ordering by an electric field. Moreover, BiFeO 3 is a promising candidate for ferroelectric memory devices because it has the largest remanent polarization ( P r >100 μC cm −2 ) of all ferroelectric materials. For these applications, controlling polarization switching by an electric field plays a crucial role. However, BiFeO 3 has a complex switching behaviour owing to the rhombohedral symmetry: ferroelastic (71 ° , 109 ° ) and ferroelectric (180 ° ) switching. Furthermore, the polarization is switched through a multi-step process: 180 ° switching occurs through three sequential 71 ° switching steps. By using monodomain BiFeO 3 thin-film heterostructures, we correlated such multi-step switching to the macroscopically observed reliability issues of potential devices such as retention and fatigue. We overcame the retention problem (i.e. elastic back-switching of the 71 ° switched area) using monodomain BiFeO 3 islands. Furthermore, we suppressed the fatigue problem of 180 ° switching, i.e. loss of switchable polarization with switching cycles, using a single 71 ° switching path. Our results provide a framework for exploring a route to reliably control multiple-order parameters coupled to ferroelastic order in other rhombohedral and lower-symmetry materials.

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Ferroelectric Polarization Switching Behavior of Hf 0.5 Zr 0.5 O 2 Gate Dielectrics on Gallium Nitride High‐Electron‐Mobility‐Transistor Heterostructures

physica status solidi (a) ◽

10.1002/pssa.201900717 ◽

2019 ◽

Vol 217 (7) ◽

pp. 1900717

Author(s):

Chunlei Wu ◽

Hansheng Ye ◽

Benjamin Grisafe ◽

Suman Datta ◽

Patrick Fay

Keyword(s):

Gallium Nitride ◽

Electron Mobility ◽

Gate Dielectrics ◽

High Electron Mobility Transistor ◽

Polarization Switching ◽

Switching Behavior ◽

Ferroelectric Polarization ◽

High Electron ◽

High Electron Mobility

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RF-Characterization of HZO Thin Film Varactors

Crystals ◽

10.3390/cryst11080980 ◽

2021 ◽

Vol 11 (8) ◽

pp. 980

Author(s):

Sukhrob Abdulazhanov ◽

Quang Huy Le ◽

Dang Khoa Huynh ◽

Defu Wang ◽

Maximilian Lederer ◽

...

Keyword(s):

Thin Film ◽

Dielectric Loss ◽

Dielectric Permittivity ◽

Electric Field ◽

Zirconium Oxide ◽

Electric Field Distribution ◽

Frequency Range ◽

Microwave Characterization ◽

Reflectivity Method

A microwave characterization at UHF band of a ferroelectric hafnium zirconium oxide metal-ferroelectric-metal (MFM) capacitors for varactor applications has been performed. By using an impedance reflectivity method, a complex dielectric permittivity was obtained at frequencies up to 500 MHz. Ferroelectric Hf0.5Zr0.5O2 of 10 nm thickness has demonstrated a stable permittivity switching in the whole frequency range. A constant increase of the calculated dielectric loss is observed, which is shown to be an effect of electric field distribution on highly resistive titanium nitride (TiN) thin film electrodes. The C-V characteristics of a “butterfly” shape was also extracted, where the varactors exhibited a reduction of capacitance tunability from 18.6% at 10 MHz to 15.4% at 500 MHz.

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Structures and local ferroelectric polarization switching properties of orthorhombic YFeO 3 thin film prepared by a sol–gel method

Chinese Physics B ◽

10.1088/1674-1056/28/3/037701 ◽

2019 ◽

Vol 28 (3) ◽

pp. 037701

Author(s):

Runlan Zhang ◽

Shuaishuai Li ◽

Changle Chen ◽

Li-An Han ◽

Shanxin Xiong

Keyword(s):

Thin Film ◽

Sol Gel ◽

Polarization Switching ◽

Ferroelectric Polarization ◽

Gel Method ◽

Sol Gel Method

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THE EFFECT OF ELECTRIC FIELD ON THE DIELECTRIC PERMITTIVITY OF BST/STO SUPERLATTICE

Modern Physics Letters B ◽

10.1142/s0217984913500668 ◽

2013 ◽

Vol 27 (10) ◽

pp. 1350066 ◽

Cited By ~ 3

Author(s):

ZHI-GAO ZUO ◽

FU-RI LING ◽

DAN LI ◽

JIN-SONG LIU ◽

JIAN-QUAN YAO

Keyword(s):

Dielectric Properties ◽

Dielectric Permittivity ◽

Electric Field ◽

External Electric Field ◽

Ferroelectric Properties ◽

Transformation Strain ◽

Elastic Interaction ◽

Dielectric Behavior ◽

Electrical Field ◽

External Electrical Field

A nonlinear thermodynamic model is developed for investigating the effect of external electric field on the dielectric properties of Ba 0.6 Sr 0.4 TiO 3/ SrTiO 3( BST / STO ) super-lattice. The transformation strain induced by the external electrical field are analyzed and calculated. It is found that the dielectric and ferroelectric properties of the ( BST / STO ) superlattice vary substantially with the interlayer elastic interaction caused by the external electrical field. The results also provide better understanding of the dielectric behavior of BST / STO superlattice with external electric field and a necessary step in the development of the general nonlinear theory.

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Tuning the Electric Field Response of MOFs by Rotatable Dipolar Linkers

10.26434/chemrxiv.8153198.v1 ◽

2019 ◽

Author(s):

Johannes P. Dürholt ◽

Babak Farhadi Jahromi ◽

Rochus Schmid

Keyword(s):

Electric Field ◽

Electric Fields ◽

Structural Changes ◽

Dielectric Behavior ◽

Two Dimensions ◽

Dielectric Constants ◽

Electric Response ◽

Dipole Strength ◽

Metal Organic ◽

Dynamics Simulations

Recently the possibility of using electric fields as a further stimulus to trigger structural changes in metal-organic frameworks (MOFs) has been investigated. In general, rotatable groups or other types of mechanical motion can be driven by electric fields. In this study we demonstrate how the electric response of MOFs can be tuned by adding rotatable dipolar linkers, generating a material that exhibits paralectric behavior in two dimensions and dielectric behavior in one dimension. The suitability of four different methods to compute the relative permittivity κ by means of molecular dynamics simulations was validated. The dependency of the permittivity on temperature T and dipole strength μ was determined. It was found that the herein investigated systems exhibit a high degree of tunability and substantially larger dielectric constants as expected for MOFs in general. The temperature dependency of κ obeys the Curie-Weiss law. In addition, the influence of dipolar linkers on the electric field induced breathing behavior was investigated. With increasing dipole moment, lower field strength are required to trigger the contraction. These investigations set the stage for an application of such systems as dielectric sensors, order-disorder ferroelectrics or any scenario where movable dipolar fragments respond to external electric fields.

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