A5026281346- Ferroelectric and Piezoelectric Materials
- Microwave Dielectric Ceramics Synthesis
- Multiferroics and related materials
- Acoustic Wave Resonator Technologies
- Advanced ceramic materials synthesis
- Electronic and Structural Properties of Oxides
- Metal and Thin Film Mechanics
- Semiconductor materials and devices
- Dielectric properties of ceramics
- Gas Sensing Nanomaterials and Sensors
- Dielectric materials and actuators
- Analytical Chemistry and Sensors
- Advanced Surface Polishing Techniques
- Ultrasonics and Acoustic Wave Propagation
- Transition Metal Oxide Nanomaterials
- Advanced materials and composites
- MXene and MAX Phase Materials
- Advanced Chemical Sensor Technologies
- Integrated Circuits and Semiconductor Failure Analysis
- Diamond and Carbon-based Materials Research
- Magnetic and transport properties of perovskites and related materials
- Electrical and Thermal Properties of Materials
- Boron and Carbon Nanomaterials Research
- 3D IC and TSV technologies
- Photorefractive and Nonlinear Optics
Silicon Austria Labs (Austria)
2024-2025
Materials Center Leoben (Austria)
2014-2023
Carl Zeiss (Germany)
2020
Montanuniversität Leoben
2010-2018
Institut Für Angewandte Kulturforschung
2016
Karlsruhe Institute of Technology
2015
Robert Bosch (Germany)
2015
Queen Mary University of London
2013
Nanoforce Technology (United Kingdom)
2013
Institute of Science and Technology for Ceramics
2005-2010
Abstract Bismuth sodium titanate (BNT)‐derived materials have seen a flurry of research interest in recent years because the existence extended strain under applied electric fields, surpassing that lead zirconate (PZT), most commonly used piezoelectric. The underlying physical and chemical mechanisms responsible for such extraordinary levels BNT are still poorly understood, as is nature successive phase transitions. A comprehensive explanation proposed here, combining short‐range structural...
Sodium bismuth titanate (NBT) ceramics are among the most promising lead-free materials for piezoelectric applications. This work reports crystal structure and phase evolution of NBT Fe-modified (from 0-2 at.$%$ Fe) using synchrotron x-ray diffraction Raman spectroscopy, at both ambient elevated temperatures. The crystallographic results discussed with reference to permittivity thermal depolarization measurements same compositions. Changes in temperature due Fe substitution were detected by...
In 0.95[0.94Bi0.5Na0.5TiO3-0.06BaTiO3]-0.05CaTiO3 ceramics, the temperature TS (dielectric permittivity shoulder at about 125 °C) represents a transition between two different thermally activated dielectric relaxation processes. Below TS, approximately linear decrease of with logarithm frequency was attributed to presence dominant ferroelectric phase. Above shows more complicated dependence and Raman modes indicate sudden increase in spatial disorder material, which is ascribed nonpolar...
The design of core–shell materials affords additional degrees freedom to tailor functional properties as compared solid solution counterparts. Although date most the work in has focused on dielectrics, piezoelectric ceramics may gain similar interest. Generalities features are addressed this work. A model system, Bi 1/2 Na TiO 3 –SrTiO , is introduced discuss structure–property relationships. We demonstrate that system a microstructure for composition corresponding 25 at.% Sr. material...
High-resolution x-ray diffraction (XRD), Raman spectroscopy and total scattering XRD coupled to atomic pair distribution function (PDF) analysis studies of the atomic-scale structure archetypal BaZrxTi1−xO3 (x = 0.10, 0.20, 0.40) ceramics are presented over a wide temperature range (100–450 K). For x 0.1 0.2 results reveal, well above Curie temperature, presence Ti-rich polar clusters which precursors long-range ferroelectric order observed below TC. Polar nanoregions (PNRs) relaxor...
Defects, in particular vacancies, play a crucial role substituted perovskite systems, influencing the structural features that underpin ferroelectricity. B-site vacancies introduce cation disorder lattice and are fact one of main driving forces for relaxor behaviour barium titanate (BaTiO3, BT) based ferroelectrics. In this work, material systems carefully selected to qualitatively study change vacancy concentration heterovalent BT-based ferroelectric polycrystals. Raman spectroscopy was...
The nature of the "forbidden" local- and long-range polar order in nominally nonpolar paraelectric phases ferroelectric materials has been an open question since discovery ferroelectricity oxide perovskites (ABO3). A currently considered model suggests locally correlated displacements B-site atoms along a subset <111> cubic directions. Such offsite have confirmed experimentally, however, being essentially dynamic they cannot account for static symmetry-forbidden polarization implied by...
Abstract Despite being applied with success in many fields of materials science, Raman spectroscopy is not yet determinant the study electroceramics. Recent experimental and theoretical developments, however, should increase popularity this class materials. In review, we outline application microscopy various electroceramic systems, defining current key bottlenecks explaining promising recent developments. We focus our attention on including coupling other methodologies modelling approaches...
BaSnxTi1−xO3 solid solutions with compositions in the range x = 0–0.20 were studied by combining analysis of field-induced dielectric and ferroelectric properties Raman spectroscopic investigations. By techniques, detection specific features related to ferroelectric-to-relaxor crossover increasing Sn content is possible. Detailed tunability 0.05 composition indicated that multiple components contribute dc-field induced permittivity response; these are active different temperature field...
Abstract Several PbZr 1− x Ti O 3 (PZT) compositions in the proximity of morphotropic phase boundary (MPB) were examined by means Raman spectroscopy 15–800 K temperature range. Previous studies performed other researchers using various techniques evidenced that, diagram PZT, areas with rhombohedral/monoclinic and tetragonal/monoclinic phases coexist across MPB. For these compositions, either long‐range or short‐range symmetry ordering monoclinic should be considered, so that no true...
The functional properties of a series BaTiO3 ceramics, having grain sizes ranging from 75 nm to 2.25 μm, with polymorph coexistence around room temperature are presented. Large ranges phase were detected through structural analyses, no apparent size effect on the extension co-existence domain, while transition temperatures vary size. Permittivity values among highest reported and typical maximum 1 μm is confirmed by low field measurements sub-switching Rayleigh analysis. An interesting...
Inducing and detecting the polar orthorhombic phase are crucial for establishment of ferroelectricity in HfO 2 ‐ ZrO ‐based thin films. Unfortunately, commonly used structural characterization techniques such as grazing incidence angle X‐ray diffraction (GIXRD) only partially allow an accurate detection this crystalline phase, whose characteristic pattern almost coincides with one tetragonal phase. As a consequence, determination is based on peak deconvolution tracing position main at θ...
Abstract Amorphous oxide thin films are crucial materials for micro- and nanoelectronics device fabrication have frequently been employed as a component of stacks (e.g., gate dielectrics), well hard masks lithography protective layers ion etching. In this work, we report a-SiOx deposited on Si substrates using reactive magnetron sputtering techniques. By adjusting the oxygen content silicon power during deposition process found that it is possible to obtain with density up 7% lower 25%...
The contribution of 180° domain wall motion to polarization and dielectric properties ferroelectric materials has yet be determined experimentally. In this paper, an approach for estimating the extent (180°) reversal during application electric fields is presented. We demonstrate method by determining in soft lead zirconate titanate strong fields. At maximum applied field, was account >80% measured macroscopic polarization. also apply quantify weak-field permittivity BaTiO3. results analysis...
It is well known that disordered relaxor ferroelectrics exhibit local polar correlations. The origin of localized fields disrupt long range order for different substitution types, however, unclear. Currently, it substituents the same valence as Ti4+ at B-site barium titanate lattice produce random disruption Ti-O-Ti chains induces behavior. On other hand, investigating and behavior resulting from more complex due to simultaneous occurrence charge imbalances displacements substituent cation....
BaCe x Ti1− O3 (x = 0.06, 0.10, and 0.20) solid solutions were prepared via conventional the solid-state reaction sintered at 1500°C for 4 h, resulting in dense single phase ceramics with homogeneous microstructures. The electric field dependence of permittivity was investigated detail, together ferroelectric–paraelectric transition features. A transformation from normal to relaxor ferroelectrics observed by increasing Ce concentration. For low-Ce content, a substitution on both B site...
The influence of a local thermal treatment on the properties Ti–Al–N coatings is not understood. In present work, Ti0.52Al0.48N coating WC–Co substrate was heated with diode laser up to 900 °C for 30 s and radially symmetric lateral gradients phases, residual stress hardness were characterized ex-situ using position-resolved synchrotron X-ray diffraction, Raman spectroscopy, transmission electron microscopy nanoindentation. results reveal (i) relaxation at edge irradiated area (ii)...