A5032028141- Ferroelectric and Piezoelectric Materials
- Acoustic Wave Resonator Technologies
- Microwave Dielectric Ceramics Synthesis
- Multiferroics and related materials
- Electronic and Structural Properties of Oxides
- Advanced MEMS and NEMS Technologies
- Advanced Sensor and Energy Harvesting Materials
- Semiconductor materials and devices
- Dielectric materials and actuators
- Innovative Energy Harvesting Technologies
- Ultrasonics and Acoustic Wave Propagation
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- Force Microscopy Techniques and Applications
- Advanced X-ray Imaging Techniques
- Magnetic and transport properties of perovskites and related materials
- Dielectric properties of ceramics
- Mechanical and Optical Resonators
- Various Chemistry Research Topics
- Advanced ceramic materials synthesis
- Ultrasound Imaging and Elastography
- Photorefractive and Nonlinear Optics
- Ferroelectric and Negative Capacitance Devices
- Metal and Thin Film Mechanics
- Gas Sensing Nanomaterials and Sensors
Pennsylvania State University
2016-2025
Millennium Engineering and Integration (United States)
2015-2024
Center for Dielectrics & Piezoelectrics
2014-2023
Norwegian University of Science and Technology
2019
University of California, Berkeley
2019
Fox Corporation (United States)
2011-2018
Xerox (France)
2011-2018
Park University
2018
Teledyne Technologies (United States)
2017-2018
Technical University of Denmark
2017-2018
ABSTRACT Crystallographic texturing of polycrystalline ferroelectric ceramics offers a means achieving significant enhancements in the piezoelectric response. Templated grain growth (TGG) enables fabrication textured with single crystal-like properties, as well crystals. In TGG, nucleation and desired crystal on aligned template particles results an increased fraction oriented material heating. To facilitate alignment during forming, must be anisometric shape. serve preferred sites for...
▪ Abstract This paper reviews the literature on size effects in ferroelectric materials, with an emphasis thin film perovskite ferroelectrics. The roles of boundary conditions, defect chemistry, electrode interfaces, surface layers, and microstructure controlling measured properties films, as well observed deviation from bulk are discussed. Examples manifestation terms low high field dielectric properties, piezoelectric effect, leakage behavior films given.
A high, temperature‐stable dielectric constant (∼1000 from 0° to 300°C) coupled with a high electrical resistivity (∼10 12 Ω·cm at 250°C) make 0.7 BaTiO 3 –0.3 BiScO ceramics an attractive candidate for high‐energy density capacitors operating elevated temperatures. Single layer were prepared confirm the feasibility of –BiScO this application. It was found that energy about 6.1 J/cm field 73 kV/mm could be achieved room temperature, which is superior typical commercial X7R capacitors....
In this article, domain wall motion and the extrinsic contributions to dielectric piezoelectric responses in sol–gel derived lead zirconate titanate (PZT) films with compositions near morphotropic phase boundary were investigated. It was found that although had different thicknesses, grain sizes, preferred orientations, similar intrinsic constants obtained for all between 0.5 3.4 μm thick. estimated about 25%–50% of response at room temperature from sources. The contribution constant PZT...
Microelectromechanical systems (MEMS) incorporating active piezoelectric layers offer integrated actuation, sensing, and transduction. The broad implementation of such MEMS has long been constrained by the inability to integrate materials with giant response, as Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT). We synthesized high-quality PMN-PT epitaxial thin films on vicinal (001) Si wafers use an SrTiO(3) template layer superior coefficients (e(31,f) = -27 ± 3 coulombs per square meter) figures...
The structural and dielectric properties of (1− x )BaTiO 3 – BiScO ( =0–0.5) ceramics were investigated to acquire a better understanding the binary system, including determination symmetry phases, associated properties, differences in roles Bi 2 O substitutions BaTiO solid solution. solubility limit for into perovskite structure was determined be about =0.4. A systematic change from ferroelectric tetragonal phase pseudo‐cubic one observed at =0.05–0.075 room temperature. Dielectric...
Ferroelectric materials are well‐suited for a variety of applications because they can offer combination high performance and scaled integration. Examples note include piezoelectrics to transform between electrical mechanical energies, capacitors used store charge, electro‐optic devices, nonvolatile memory storage. Accordingly, widely as sensors, actuators, energy storage, components, ultrasonic in consumer electronics products. Because these functional properties arise from...
Piezoelectric materials convert between electrical and mechanical energies such that an applied stress induces a polarization electric field strain. This review describes the fundamental mechanisms governing piezoelectric response in high-performance single crystals, ceramics, thin films. While there are number of useful small molecules polymers, article focuses on inorganic displaying effect. Piezoelectricity is first defined, contribute discussed terms key crystal structures for with large...
This article provides the latest advances from NSF Advanced Self-powered Systems of Integrated sensors and Technologies (ASSIST) center. The work in center addresses key challenges wearable health environmental systems by exploring technologies that enable ultra-long battery lifetime, user comfort wearability, robust medically validated sensor data with value added multimodal sensing, access to open architecture streams. vison ASSIST is use nanotechnology build miniature, self-powered,...
Abstract Antiferroelectric (AFE) materials are of great interest owing to their scientific richness and utility in high‐energy density capacitors. Here, the history AFEs is reviewed, characteristics antiferroelectricity phase transition an AFE material described. energetically close ferroelectric (FE) phases, thus both electric field strength applied stress (pressure) influence nature transition. With comparable energetics between FE there can be a competition frustration these either...
This manuscript demonstrates ferroelectricity in B-substituted AlN thin films and a complementary set of first-principles calculations to understand their structure-property relationships. ${\mathrm{Al}}_{1--x}{\mathrm{B}}_{x}\mathrm{N}$ are grown by dual-cathode reactive magnetron sputtering on $(110)\mathrm{W}/(001){\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ substrates at 300\ifmmode^\circ\else\textdegree\fi{}C compositions spanning $x=0$ $x=0.20$. X-ray diffraction studies indicate decrease both...
We demonstrate ferroelectricity in Mg-substituted ZnO thin films with the wurtzite structure. Zn1−xMgxO are grown by dual-cathode reactive magnetron sputtering on (111)-Pt // (0001)-Al2O3 substrates at temperatures ranging from 26 to 200 °C for compositions spanning x = 0 0.37. X-ray diffraction indicates a decrease c-lattice parameter and an increase a-lattice increasing Mg content, resulting nearly constant c/a axial ratio of 1.595 over this composition range. Transmission electron...
Ferroelectric wurtzites have the potential to revolutionize modern microelectronics because they are easily integrated with multiple mainstream semiconductor platforms. However, electric fields required reverse their polarization direction and unlock electronic optical functions need substantial reduction for operational compatibility complementary metal-oxide (CMOS) electronics. To understand this process, we observed quantified real-time switching of a representative ferroelectric wurtzite...
Textured bismuth titanate, Bi 4 Ti 3 O 12 (BiT), was produced by templated grain growth (TGG). Molten‐salt‐synthesized BiT platelets were dispersed in a matrix of 200 nm powder and aligned tape casting. Highly textured obtained with the use only 5 vol% template particles sintering at 1000°C for 1 h. The uniformity through‐thickness texture is much higher than reported literature tapes cast 100% platelets. Initial platelet alignment shown to increase because frequent interaction fine during...
Bi 2 O 3 –ZnO–Nb 5 pyrochlore thin films were prepared on platinum coated Si wafers using a metalorganic deposition process. The structures, morphologies, and dielectric properties of with two compositions: (Bi1.5Zn0.5)(Zn0.5Nb1.5)O7 Bi2(Zn1/3Nb2/3)2O7, investigated. Thin have cubic phase when crystallized at 550 °C or higher. crystal structure Bi2(Zn1/3Nb2/3)2O7 was dependent the firing temperature; showed temperatures below 650 °C, pseudo-orthorhombic 750 °C. A mixture structures found in...
Single crystals of Ba(ZrxTi1−x)O3 were grown by templated grain growth (TGG). Millimeter size single produced heating a BaTiO3 crystal in contact with sintered polycrystalline matrix 4.5, 5.0, or 8.5 mol % Zr-doped barium titanate for 30 h at 1350 °C. To facilitate boundary migration, the ceramic compact was made 3 TiO2 excess. The 4.5 and 5.0 orthorhombic room temperature, pseudocubic (001) orientation, they showed remanent polarizations 13 μC/cm2 high field d33 340–355 pC/N. [again...
Scanning force microscopy (SFM) has been used for the determination of friction, phase transformation, piezoelectric behavior (in contact mode), polarization state, and dielectric constant noncontact mode) nanometer regions lead zirconate titanate (PZT) films. The use SFM tip in mode, to polarize different nanoregions PZT film apply an oscillating field thereon, led effective coefficients loops. measured coefficient was shown depend appreciably on both quality tip-to-film electrical contact....
The complex dielectric response of ${\mathrm{Bi}}_{1.5}{\mathrm{Zn}}_{1.0}{\mathrm{Nb}}_{1.5}{\mathrm{O}}_{7}$ cubic pyrochlore ceramics was investigated between 100 Hz and THz by a combination low-frequency capacitance bridges, high-frequency coaxial technique, time domain transmission spectroscopy, infrared spectroscopy. data obtained 10 K 400 revealed glasslike behavior: relaxation is observed over wide frequency temperature range, the permittivity loss maxima shift to higher values...
The piezoelectric properties of (1−x) Pb(Mg1/3Nb2/3)O3–xPbTiO3 (x=0.3–0.35), ceramics with a high degree 〈001〉 fiber texture were investigated for possible actuator applications. Piezoelectric coefficients (d33) in excess 1200 pC/N associated strain levels up to >0.3% observed samples prepared by reactive templated grain growth process. No PbO was used the starting composition. A achieved using oriented BaTiO3 template particles fine-grained precursor PMN–32PT matrix. High densities...