Download or read book Switchable and Tunable Bulk Acoustic Wave Devices Based on Ferroelectric Material written by Almonir Abdulgader Mansour and published by . This book was released on 2017 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: The explosive development of personal communications systems, navigation, satellite communications as well as personal computer and data processing systems together with the constant demand for higher speeds and larger bandwidths has driven fabrication technology to its limits. This, in turn, necessitates the development of novel functional materials for the fabrication of devices with superior performance and higher capacity at reduced manufacturing costs. Ferroelectric materials such as barium strontium titanate (BST) and strontium titanium oxide (STO) have received more attention by researchers and industry because of their field-induced piezoelectric property. This property gives these types of ferroelectric materials the ability to be switchable and tunable in the presence of an electric field. These features have allowed the ferroelectric materials to be used in many applications such as non-volatile memory and DRAMs, sensors, pyroelectric detectors, and tunable microwave devices. Therefore, with the ever increasing complexity in RF front-end receivers, and the demand for services (which in turn requires more functionalities), ferroelectric bulk acoustic wave (BAW) resonators and filters that are intrinsically switchable and promise to reduce the size and complexity of component parts. In this work, we present the design, fabrication and experimental evaluation of switchable and tunable thin film bulk acoustic wave (BAW) resonators, filters and duplexers for radio frequency (RF) applications. The switchability and tunability of these devices come from utilizing the electrostrictive effect of ferroelectric materials such as barium strontium titanate (BST) with the application of an external DC-bias voltage. The BAW resonators, filters and duplexers in this work were fabricated on different substrates as solidly mounted resonator (SMR) structure with number of periodic layers of silicon dioxide and tantalum oxide as a Bragg reflector in order to acoustically isolate the resonator from the damping effect of the substrate, enhancing the quality factor and temperature compensation.

Download or read book Switchable and Tunable Ferroelectric Bulk Acoustic Wave Resonators and Filters written by George Nabih Saddik and published by . This book was released on 2011 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: BST tunable capacitors have always had anomalous resonances in the one port scattering parameter measurements, although they are very small they degrade the quality factor of the device, and research went into reducing these resonances as much as possible.

Download or read book Switchable and Tunable Bulk Acoustic Wave Resonators Based on BaxSr1 xTiO3 Thin Films written by John Berge and published by . This book was released on 2012 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tuneable Film Bulk Acoustic Wave Resonators written by Spartak Gevorgian and published by Springer. This book was released on 2013-03-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: To handle many standards and ever increasing bandwidth requirements, large number of filters and switches are used in transceivers of modern wireless communications systems. It makes the cost, performance, form factor, and power consumption of these systems, including cellular phones, critical issues. At present, the fixed frequency filter banks based on Film Bulk Acoustic Resonators (FBAR) are regarded as one of the most promising technologies to address performance -form factor-cost issues. Even though the FBARs improve the overall performances the complexity of these systems remains high. Attempts are being made to exclude some of the filters by bringing the digital signal processing (including channel selection) as close to the antennas as possible. However handling the increased interference levels is unrealistic for low-cost battery operated radios. Replacing fixed frequency filter banks by one tuneable filter is the most desired and widely considered scenario. As an example, development of the software based cognitive radios is largely hindered by the lack of adequate agile components, first of all tuneable filters. In this sense the electrically switchable and tuneable FBARs are the most promising components to address the complex cost-performance issues in agile microwave transceivers, smart wireless sensor networks etc. Tuneable Film Bulk Acoustic Wave Resonators discusses FBAR need, physics, designs, modelling, fabrication and applications. Tuning of the resonant frequency of the FBARs is considered. Switchable and tuneable FBARs based on electric field induced piezoelectric effect in paraelectric phase ferroelectrics are covered. The resonance of these resonators may be electrically switched on and off and tuned without hysteresis. The book is aimed at microwave and sensor specialists in the industry and graduate students. Readers will learn about principles of operation and possibilities of the switchable and tuneable FBARs, and will be given general guidelines for designing, fabrication and applications of these devices.

Download or read book Fabrication of Electronically Switchable and Tunable Bulk Acoustic Wave Resonators with Graphene Electrodes written by Wei Liu and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication of Ferroelectrics Based MEMS Structures for Electronically Switchable Bulk Acoustic Wave Resonators written by Tian Le Wang and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thin Film Ferroelectric Tunable Devices for Reconfigurable Radios written by and published by . This book was released on 2008 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper, a summary of our work in the area of tunable microwave circuits based on thin film ferroelectrics is presented. First, a technique is introduced to improve the linearity of thin film ferroelectric tunable capacitors. Measurements show an improvement in the 3rd order intermodulation point at the input (IIP3) of 16 dB. Next, the design and fabrication of an impedance tuner employing thin film ferroelectric capacitors for applications in adaptive matching networks is described. An impedance tuning ratio of 4:1 was achieved. Lastly, the fabrication of a switchable thin film bulk wave acoustic resonator (FBAR) and its application in the design of switchable filters are discussed. The resonator is measured to have a series resonance of 1.975 GHz with a Q factor of 233 and a parallel resonance of 2.035 GHz with a Q factor of 218. The resonator is proposed to construct a switchable bandpass filter.

Download or read book Tunable Bulk Acoustic Wave Resonators Based on BaxSr1 xTiO3 Thin Films written by John Berge and published by . This book was released on 2009 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling of Structural Elastic and Polar Properties of Organic and Inorganic Ferroelectrics written by Fu-Chang Sun and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational materials science has become an important branch of research with the advent of high performance computers and efficient algorithms. The viability of solving fundamental theories allows not only to understand experimental results, but predict properties of exotic materials or materials at extreme conditions. There exists fundamental theories that has been applied in different domains of length and time scales, where certain approximations are employed which enable improved performance with minimum compromise of accuracy. In this Thesis, various computational approaches at different length scales are considered to investigate different classes of organic and inorganic ferroelectric materials to describe structural-property relations. The in-plane and out-of-plane piezoelectric properties of (001) strontium titanate (SrTiO$_3$, STO) epitaxial thin films on pseudo-cubic (001) substrates are computed as a function of in-plane misfit strain. A nonlinear thermodynamic model is employed, which takes into account the appropriate mechanical boundary conditions, the electromechanical coupling between the polarization and the in-plane lattice mismatch, and the self-strains of the ferroelastic and ferroelectric phase transformations. The piezoelectric behavior of epitaxial STO films is described in various strain-induced ferroelectric phase fields in a temperature range from $-$50 to 50 $\degree$C. These results indicate that strain engineered STO films may be employed in a variety of sensor and actuator applications as well as surface acoustic wave devices and thin-film bulk acoustic resonators. Implementing the same technique, piezoelectric properties of epitaxial (001) barium strontium titanate (BST) films are computed as functions of composition, misfit strain, and temperature using a non-linear thermodynamic model. Results show that through adjusting in-plane strains, a highly adaptive rhombohedral ferroelectric phase can be stabilized at room temperature with outstanding piezoelectric response exceeding those of lead based piezoceramics. Furthermore, by adjusting the composition and the in-plane misfit, an electrically tunable piezoelectric response can be obtained in the paraelectric state. These findings indicate that strain engineered BST films can be utilized in the development of electrically tunable and switchable surface and bulk acoustic wave resonators. The theoretical model of ferroelectric bilayers using basic thermodynamics taking into account the appropriate electrical boundary conditions and electrostatic fields is present. We show that ferroelectric multilayers are not simple capacitors in series (CIS) and treating these as CIS may lead to misinterpretation of experimental results and to erroneous conclusions. The spontaneous polarization mismatch in ferroelectric/ferroelectric (FE/FE), FE/paraelectric (FE/PE), and FE/dielectric (FE/DE) bilayers results in a non-linear electrostatic coupling which produces significant deviations in the overall dielectric response if it is computed using the simple capacitor-in-series (CIS) model. Our results show that the CIS approach is a good approximation only for DE/DE multilayers and for FE heterostructures if the individual layers are electrostatically screened from each other. As a second method for this Thesis, classical molecular dynamics computations are considered to calculate the structural, elastic, and polar properties of crystalline ferroelectric $\beta$ phase poly(vinylidene fluoride), PVDF, with randomized trifluoroethylene TrFE as a function of TrFE content. The results show that molecular dynamics can be used to predict the mechanical and polarization-related behavior of ferroelectric poly(VDF\textit{-co-}TrFE). The same computational approach might be also utilized for other polymeric materials in the desired temperature and/or composition range. Furthermore, temperature-induced and deformation-induced phase transitions are reported, which are consistent with the experimental observation. Finally, the fundamental theory of electron physics, also called the first-principles formalism, is applied to study the polarization of the layered ferroelectric bismuth titanate (BiT). The electronic structure studies of pure BiT and technologically significant lanthanum-doped bismuth titanate (La-doped BiT) are performed. The results and the extension of current progress of A-site substitutional BiT using first-principle calculations could provide the theoretical evidence of the formation of oxygen vacancies, which is recognized to be associated with the leakage current and polarization properties. Studies on the optical properties of BiT are performed using a beyond-density functional theory (beyond-DFT) method. This is done because the regular approximation for electron-electron coupling in the DFT specific generalized gradient approximation (GGA) has limitations in predicting the band gap of semiconductors/insulators. The Heyd-Scuseria-Ernzerhof (HSE) screened hybrid-functional method is adopted.

Download or read book Ferroelectric Thin Films written by Masanori Okuyama and published by Springer Science & Business Media. This book was released on 2005-02-22 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferroelectric thin films continue to attract much attention due to their developing applications in memory devices, FeRAM, infrared sensors, piezoelectric sensors and actuators. This book, aimed at students, researchers and developers, gives detailed information about the basic properties of these materials and the associated device physics. The contributing authors are acknowledged experts in the field.

Download or read book Polar Oxides written by Rainer Waser and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, more than 20 experts from leading research institutes around the world present the entire scope of this rapidly developing field. In so doing, they cover a wide range of topics, including the characterization and investigation of structural, dielectric and piezoelectric properties of ceramic materials, a well as phase transitions, electrical and optical properties and microscopic investigations. Another feature is a complete profile of the properties of polar oxides -- from their proof to their latest applications. Throughout, the authors review, discuss and assess the material properties with regard to new and advanced characterization and imaging techniques. For physicists, physicochemists, semiconductor and solid state physicists, materials scientists, and students of chemistry and physics.

Download or read book Ferroelectric Materials for Energy Applications written by Haitao Huang and published by John Wiley & Sons. This book was released on 2019-01-04 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a comprehensive overview of the emerging applications of ferroelectric materials in energy harvesting and storage Conventional ferroelectric materials are normally used in sensors and actuators, memory devices, and field effect transistors, etc. Recent progress in this area showed that ferroelectric materials can harvest energy from multiple sources including mechanical energy, thermal fluctuations, and light. This book gives a complete summary of the novel energy-related applications of ferroelectric materials?and reviews both the recent advances as well as the future perspectives in this field. Beginning with the fundamentals of ferroelectric materials, Ferroelectric Materials for Energy Applications offers in-depth chapter coverage of: piezoelectric energy generation; ferroelectric photovoltaics; organic-inorganic hybrid perovskites for solar energy conversion; ferroelectric ceramics and thin films in electric energy storage; ferroelectric polymer composites in electric energy storage; pyroelectric energy harvesting; ferroelectrics in electrocaloric cooling; ferroelectric in photocatalysis; and first-principles calculations on ferroelectrics for energy applications. -Covers a highly application-oriented subject with great potential for energy conversion and storage applications. -Focused toward a large, interdisciplinary group consisting of material scientists, solid state physicists, engineering scientists, and industrial researchers -Edited by the "father of integrated ferroelectrics" Ferroelectric Materials for Energy Applications is an excellent book for researchers working on ferroelectric materials and energy materials, as well as engineers looking to broaden their view of the field.

Download or read book Conference Papers Index written by and published by . This book was released on 1979 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monthly. Papers presented at recent meeting held all over the world by scientific, technical, engineering and medical groups. Sources are meeting programs and abstract publications, as well as questionnaires. Arranged under 17 subject sections, 7 of direct interest to the life scientist. Full programs of meetings listed under sections. Entry gives citation number, paper title, name, mailing address, and any ordering number assigned. Quarterly and annual indexes to subjects, authors, and programs (not available in monthly issues).

Download or read book Magnetoelectric Composites written by Mirza I. Bichurin and published by CRC Press. This book was released on 2019-02-22 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is dedicated to modeling and application of magnetoelectric (ME) effects in layered and bulk composites based on magnetostrictive and piezoelectric materials. Currently, numerous theoretical and experimental studies on ME composites are available but few on the development and research of instruments based on them. So far, only investigation of ME magnetic field sensors has been cited in the existing literature. However, these studies have finally resulted in the creation of low-frequency ME magnetic field sensors with parameters substantially exceeding the characteristics of Hall sensors. The book presents the authors’ many years of experience gained in ME composites and through creation of device models based on their studies. It describes low-frequency ME devices, such as current and position sensors and energy harvesters, and microwave ME devices, such as antennas, attenuators, filters, gyrators, and phase shifters.

Download or read book Piezoelectric Energy Harvesting written by Alper Erturk and published by John Wiley & Sons. This book was released on 2011-04-04 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: The transformation of vibrations into electric energy through the use of piezoelectric devices is an exciting and rapidly developing area of research with a widening range of applications constantly materialising. With Piezoelectric Energy Harvesting, world-leading researchers provide a timely and comprehensive coverage of the electromechanical modelling and applications of piezoelectric energy harvesters. They present principal modelling approaches, synthesizing fundamental material related to mechanical, aerospace, civil, electrical and materials engineering disciplines for vibration-based energy harvesting using piezoelectric transduction. Piezoelectric Energy Harvesting provides the first comprehensive treatment of distributed-parameter electromechanical modelling for piezoelectric energy harvesting with extensive case studies including experimental validations, and is the first book to address modelling of various forms of excitation in piezoelectric energy harvesting, ranging from airflow excitation to moving loads, thus ensuring its relevance to engineers in fields as disparate as aerospace engineering and civil engineering. Coverage includes: Analytical and approximate analytical distributed-parameter electromechanical models with illustrative theoretical case studies as well as extensive experimental validations Several problems of piezoelectric energy harvesting ranging from simple harmonic excitation to random vibrations Details of introducing and modelling piezoelectric coupling for various problems Modelling and exploiting nonlinear dynamics for performance enhancement, supported with experimental verifications Applications ranging from moving load excitation of slender bridges to airflow excitation of aeroelastic sections A review of standard nonlinear energy harvesting circuits with modelling aspects.

Download or read book Surface Chemistry and Catalysis written by Michalis Konsolakis and published by MDPI. This book was released on 2018-09-27 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Surface Chemistry and Catalysis" that was published in Catalysts

Download or read book Nano CMOS and Post CMOS Electronics written by Saraju P. Mohanty and published by IET. This book was released on 2016-04-12 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over two volumes this work describes the modelling, design, and implementation of nano-scaled CMOS electronics, and the new generation of post-CMOS devices, at both the device and circuit levels.