Lead-Free Piezoelectrics


Book Description

Ecological restrictions in many parts of the world are demanding the elimination of Pb from all consumer items. At this moment in the piezoelectric ceramics industry, there is no issue of more importance than the transition to lead-free materials. The goal of Lead-Free Piezoelectrics is to provide a comprehensive overview of the fundamentals and developments in the field of lead-free materials and products to leading researchers in the world. The text presents chapters on demonstrated applications of the lead-free materials, which will allow readers to conceptualize the present possibilities and will be useful for both students and professionals conducting research on ferroelectrics, piezoelectrics, smart materials, lead-free materials, and a variety of applications including sensors, actuators, ultrasonic transducers and energy harvesters.




Ferroelectric Domain Walls


Book Description

Using the nano metric resolution of atomic force microscopy techniques, this work explores the rich fundamental physics and novel functionalities of domain walls in ferroelectric materials, the nano scale interfaces separating regions of differently oriented spontaneous polarization. Due to the local symmetry-breaking caused by the change in polarization, domain walls are found to possess an unexpected lateral piezoelectric response, even when this is symmetry-forbidden in the parent material. This has interesting potential applications in electromechanical devices based on ferroelectric domain patterning. Moreover, electrical conduction is shown to arise at domain walls in otherwise insulating lead zirconate titanate, the first such observation outside of multiferroic bismuth ferrite, due to the tendency of the walls to localize defects. The role of defects is then explored in the theoretical framework of disordered elastic interfaces possessing a characteristic roughness scaling and complex dynamic response. It is shown that the heterogeneous disorder landscape in ferroelectric thin films leads to a breakdown of the usual self-affine roughness, possibly related to strong pinning at individual defects. Finally, the roles of varying environmental conditions and defect densities in domain switching are explored and shown to be adequately modelled as a competition between screening effects and pinning.




Ferroelectric Materials and Their Applications


Book Description

This book presents the basic physical properties, structure, fabrication methods and applications of ferroelectric materials. These are widely used in various devices, such as piezoelectric/electrostrictive transducers and actuators, pyroelectric infrared detectors, optical integrated circuits, optical data storage, display devices, etc. The ferroelectric materials described in this book include a relatively complete list of practical and promising ferroelectric single crystals, bulk ceramics and thin films. Included are perovskite-type, lithium niobate, tungsten-bronze-type, water-soluable crystals and other inorganic materials, as well as organic ferroelectrics (polymers, liquid crystals, and composites). Basic concepts, principles and methods for the physical property characteristics of ferroelectric materials are introduced in the first two chapters for those readers new to the subject of ferroelectricity. Not only professional researchers and engineers but also students and other readers who have limited physical knowledge and an interest in ferroelectrics, will welcome this book.




Photoferroelectrics


Book Description

Since Valasek's discovery of the ferroelectric properties of Rochelle salt nearly 60 years ago, ferroelectricity has been regarded as one of the tradi tional branches of dielectric physics. It has had important applications in lattice dynamics, quantum electronics, and nonlinear optics. The study of electron processes in ferroelectrics was begun with VUL's investigations of the ferroelectric properties of barium titanate [1.1]. In trinsic and extrinsic optical absorption, band structure, conductivity and photoconductivity, carrier mobility. and transport mechanisms were examined in this compound, and in other perovskite ferroelectric semiconductors. An important discovery was that of the highly photosensitive photoconducting ferroelectrics of type AVBVICVIII (e.g. SbSI) by MERZ et al. in 1962 [1.2,3]. A large number of ferroelectric semiconductors (some photosensitive, some not) are now known, including broad-band materials (e.g. lithium niobate, lithium tantalate, barium and strontium niobate, and type-A~B~I compounds), BI and narrow-band semiconductors (e.g. type_AIVB compounds). A series of improper ferroelectric semiconductors and photosensitive ferroelastics have been discovered, of which Sb 0 I is an example. s 7 Owing to the uncertainty of their band structure, the difficulty in deter mining the nature of the levels, the complexity of alloying, and their gen erally low mobility values, ferroelectrics are rarely of interest regarded as nonlinear semiconductors. The most fruitful approach has been the study of the influence of electrons (especially nonequilibrium electrons) and electron excitations on phase transitions and ferroelectric properties. A large group of phenomena have recently been discovered and investigated.




Lead-Free Piezoelectric Materials


Book Description

Provides in-depth knowledge on lead-free piezoelectrics - for state-of-the-art, environmentally friendly electrical and electronic devices! Lead zirconate titanate ceramics have been market-dominating due to their excellent properties and flexibility in terms of compositional modifications. Driven by the Restriction of Hazardous Substances Directive, there is a growing concern on the toxicity of lead. Therefore, numerous research efforts were devoted to lead-free piezoelectrics from the beginning of this century. Great progress has been made in the development of high-performance lead-free piezoelectric ceramics which are already used, e.g., for power electronics applications. Lead-Free Piezoelectric Materials provides an in-depth overview of principles, material systems, and applications of lead-free piezoelectric materials. It starts with the fundamentals of piezoelectricity and lead-free piezoelectrics. Then it discusses four representative lead-free piezoelectric material systems from background introduction to crystal structures and properties. Finally, it presents several applications of lead-free piezoelectrics including piezoelectric actuators, and transducers. The challenges for promoting applications will also be discussed. Highly attractive: Lead-free piezoelectrics address the growing concerns on exclusion of hazardous substances used in electrical and electronic devices in order to protect human health and the environment Thorough overview: Covers fundamentals, different classes of materials, processing and applications Unique: discusses fundamentals and recent advancements in the field of lead-free piezoelectrics Lead-Free Piezoelectric Materials is of high interest for material scientists, electrical and chemical engineers, solid state chemists and physicists in academia and industry.




Ferroelectric Devices


Book Description

Updating its bestselling predecessor, Ferroelectric Devices, Second Edition assesses the last decade of developments—and setbacks—in the commercialization of ferroelectricity. Field pioneer and esteemed author Uchino provides insight into why this relatively nascent and interdisciplinary process has failed so far without a systematic accumulation of fundamental knowledge regarding materials and device development. Filling the informational void, this collection of information reviews state-of-the-art research and development trends reflecting nano and optical technologies, environmental regulation, and alternative energy sources. Like the first edition, which became a standard in the field, this volume provides a general introduction to ferroelectrics with theoretical background. It then addresses practical design and device manufacturing, including recently developed processes and applications. Updating old data with a forecast of future developments, the text analyzes improvements to original ferroelectric devices to aid the design process of new ones. The second edition includes new sections on: Pb-free piezoelectrics Size effect on ferroelectricity Electrocaloric devices Micro mass sensor Piezoelectric energy harvesting Light valves and scanners Multi-ferroic devices, including magneto-electric sensors Uchino provides a general introduction to the theoretical background of ferroelectric devices, practical materials, device designs, drive/control techniques, and typical applications. He presents frequently asked questions from students, lab demonstrations for practical understanding, and "check point" quizzes and model solutions to monitor understanding. After a thorough exploration of ferroelectric devices and their past, this book looks to the industry’s future, assessing market size and remaining reliability/lifetime issues. The author also unveils his strategy for developing "best-selling" ferroelectric devices.




Ferroelectric Thin Films


Book Description

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.




Magnetoelectric Composites


Book Description

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.




Broadband Dielectric Spectroscopy


Book Description

Both an introductory course to broadband dielectric spectroscopy and a monograph describing recent dielectric contributions to current topics, this book is the first to cover the topic and has been hotly awaited by the scientific community.




Progress in Advanced Dielectrics


Book Description

Dielectrics is becoming increasingly important due to the rapid developments in electronics, optoelectronics, photonics and nanotechnology. In the past two decades, research on advanced dielectric materials and related applications has undergone an accelerated growth, due in larger part to the discovery of the superior piezoelectric properties in relaxor single crystals, the development of the lead-free piezoelectric/ferroelectric materials and the renaissance of the multiferroics. This book contains 9 feature articles which, together, provide a comprehensive account on the current state of advanced dielectrics and related phenomena. The first two articles present fundamental knowledge related to the characterization of ferroelectric hysteresis, which is the most widely used method to learn the ferroelectricity experimentally. The latest research progress in relaxor ferroelectric is given in the next two articles. The last five articles are dedicated to the multi-functionality of advanced dielectrics, with emphasis on multiferroic magnetoelectric composites, lead-free piezoceramics, pyroelectric/electrocaloric materials, polymer-based dielectrics, and flexible nanodielectrics.