Download or read book Pulsed Laser Deposition of Relaxor Ferroelectric Lead Magnesium Niobate lead Titanate Thin Films and Heterostructures written by Dan Silviu Lavric and published by . This book was released on 2000 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ELECTROMECHANICAL CHARACTERIZATION OF LEAD MAGNESIUM NIOBATE BASED THIN FILMS written by Smitha Shetty and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Lead Magnesium Niobate (PMN) is the most studied relaxor ferroelectric compound with cation order intimately interacting with nanoscale polar heterogeneities. In undoped bulk PMN, the cation order can hardly be changed, while the polar order is quite responsive to external stimuli (electric field and temperature). Moreover, PMN-based oxides are of technological importance, displaying strong piezoelectric effects, high electrostrictive strains, and unusually high dielectric permittivity. The local compositional heterogeneity associated with short-range ordering of Mg and Nb in PbMg1/3Nb2/3O3 (PMN) is correlated with its characteristic relaxor ferroelectric behavior. Fully-ordered PMN has not been prepared as a bulk material. This work reports the growth and characterization of thin film PMN heterostructures with long-range cation order. These films were grown at temperatures below 1073 K by artificially reducing the degree of disorder via synthesis of heterostructures with alternate layers of Pb(Mg2/3Nb1/3)O3 and PbNbO3, as suggested by the random-site model. 100-nm-thick, phase-pure films were grown epitaxially on (111) SrTiO3 substrates using alternate target timed pulsed-laser deposition of Pb(Mg2/3Nb1/3)O3 and PbNbO3 targets with 20% excess Pb. Selected area electron diffraction confirmed the emergence of (1/2, 1/2, 1/2) superlattice spots with randomly distributed ordered domains as large as ~150 nm. These heterostructures exhibited a dielectric constant of 800, loss tangents of ~0.03 and 2 x remanent polarization of ~11 C/cm2 at room temperature. Polarization-electric field hysteresis loops, Rayleigh data, and optical second-harmonic generation measurements are consistent with the development of ferroelectric domains below 140 K. Temperature-dependent permittivity measurements demonstrate reduced frequency dispersion compared to short range ordered PMN films. Although perfectly layered heterostructures could not be grown, the novelty of this work lies in achieving the highest cation order in PMN. Further, these engineered films exhibit a continuum between normal and relaxor ferroelectric behavior as a function of temperature. The dynamic nonlinear dielectric responses were also studied as a function of temperature and electric field for the PMN thin films with long- and short-range ordering. It was found that long-range ordering decreased the dispersion in the first and third harmonic displacement current relative to short-range ordered films. For both sets of films, a second harmonic component of the dielectric response was also detected. The phase angles of the higher harmonic responses were used to probe the continuum in ferroelectric- relaxor behavior in these films. At high temperatures (e.g. above the freezing temperature), the presence of nanopolar clusters is believed to cause the strong dispersion in the third harmonic response in both long range and short-range films. However, at lower temperatures, changes in the sign of 3 suggest long-range ferroelectric ordering, such that the response of mobile interfaces (believed to be domain walls) dominate the response. Additionally, miniaturization of PMN based ferroelectric films for actuator applications necessitates quantification of piezoelectric properties with scaling. A single beam laser interferometer based on a modified Mirau detection scheme with a vertical resolution of 5pm was developed for localized d33 measurements on patterned piezoelectric films. The tool provides high spatial resolution (2m), essential for understanding scaling and processing effects in piezoelectric materials. This approach enables quantitative information on d33, currently difficult in local measurement techniques such as piezoresponse force microscopy. The interferometer is built in a custom microscope and employs a phase lock-in technique in order to detect sub-Angstrom displacements. d33 measurements on single crystal 0.67PbMg0.33Nb0.67O3-0.33PbTiO3 and bulk PbZrTiO3-5A ceramics demonstrated agreement within

Download or read book Multilayers And Artificial Superlattices Of Lead Magnesium Niobate Lead Titanate Based Relaxors written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The present research work mainly focuses on fabrication of compositionally modulated multilayers of (l−x) Pb(Mgi/3N2/3)O3 - x PbTiO3 (PMNPT) through multi target pulsed laser ablation technique. Heterostructures like compositionally varying multilayers; multilayers with graded interface and a ferroelectric [PbTiO3 (PT)] and relaxor (PMN) superlattices of different periodicities were fabricated. Role of artificially enhanced chemical heterogeneity and strain on enhancement of physical property was studied. Dimensional dependent ferroelectric and antiferroelectric type of polarization behavior was observed in the case of both compositionally varying multilayers and the superlattice structures fabricated. The dimensional dependence of various ferroelectric interactions like long-range, short-range and interfacial coupling among the layers was studied. The phase transition behavior and dielectric studies were carried out on these heterostructures. An artificial superlattice of a relaxor ferroelectric with a ferromagnetic layer was also fabricated for magnetoelectric applications. Chapter 1 provides a brief introduction to ferroelectric (FE) heterostructures, their technological applications and the fundamental physics involved in ferroelectric heterostructures. Initially an introduction to the technological importance and advantages of ferroelectric heterostructures is provided. A brief introduction to relaxor ferroelectrics and their characteristic structural features are discussed. A brief review of the ferroelectric heterostructures both from fundamental science and technological point of view is provided. Finally the specific objectives of the current research are outlined. Chapter 2 deals with the various experimental studies carried out in this research work. It gives the details of the experimental set up and the basic operation principles of various structural and physical characterizations of the materials prepared. A brief explanation of material fabrication,

Download or read book Formation and Characterization of Ferroelectric Thin films Deposited by Pulsed laser Ablation written by Christopher Scarfone and published by . This book was released on 1991 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Electrical and Photoferroelectric Properties of Lead Zirconate Titanate Thin Films Prepared by Pulsed Laser Deposition for Ferroelectric Memories written by Jaichan Lee and published by . This book was released on 1993 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Properties of Lead Magnesium Niobate lead Titanate PMN PT and Strontium Barium Niobate SBN Thin Films written by Ka-yi Chan and published by . This book was released on 2005 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pulsed Laser Deposition of Lead Zirconate Titanate Thin Films written by Lucymarie Mantese and published by . This book was released on 1992 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Phase Transition Characteristics of Doped Lead Magnesium Niobate Lead Titanate Relaxor Ferroelectrics written by Edgar Robert Seydel and published by . This book was released on 1996 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ceramic Abstracts written by and published by . This book was released on 1998 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pulsed Excimer Laser Deposition of Ferroelectric Thin Films written by S. B. Krupanidhi and published by . This book was released on 1991 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pulsed UV excimer laser ablation was employed to deposit multi-axial, bi-axial and uni-axial ferroelectric compositions of PZT, bismuth titanate and lead germanate respectively. In general, a fluence lower than 2 J/cm2 caused a preferential evaporation of volatile components, resulting in stoichiometric imbalance. However, the fluences beyond 2 J/cm2 enabled the deposition of stoichiometric thin films of multi-component oxide systems. The intrinsic bombardment due to the energetic ablated species during the thin film deposition seemed to influence the composition, structure, orientation and the electrical properties. The electrical characterization of ferroelectric films indicated a dielectric constant of 800-1000, a P, of 32 micron C/cm2 and E sub c of 130KV/cm for polycrystalline PZT films and the corresponding quantities were measured to be 150, 7 micron C/cm2 and 20 KV/cm for in-situ crystallized c-axis preferred oriented bismuth titanate films. Lead germanate thin films oriented along c-axis (OO3) showed a dielectric constant of 30, a P sub r of 2.5 micron C/cm2 and E sub c of 55 KV/cm.

Download or read book Growth of Heteroepitaxial Single Crystal Lead Magnesium Niobate lead Titanate Thin Films on R plane Sapphire Substrates written by Madhana Sunder and published by . This book was released on 2009 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1996 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growth of Optical Quality Lead Magnesium Niobate lead Titanate Thick Films written by Kyle French and published by . This book was released on 2019 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Investigation Into Controlling the Growth Modes of Ferroelectric Thin Films Using Pulsed Laser Deposition and RHEED written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film ferroelectricss are widely considered for tunable microwave applications, the reduced small dimensions leading to low tuning voltages. The incipient ferroelectric strontium titanate is an ideal solution for tunable microwave devices, particularly in conjunction with high temperature superconductors. It has no spontaneous polarisation yet possesses a large permittivity at low temperatures that is sensitive to an electric field bias with relatively low loss. For such applications it is essential to use a low loss substrate such as magnesium oxide. In general, thin films have less favourable dielectric properties compared with their bulk counterparts due to differences in microstructure. strontium titanate films on MgO substrate prove difficult to grow due to the high lattice mismatch and issues connected with chemical incompatibility at the film/substrate interface. It has been shown here that it is possible to engineer the growth mode of this system, altering the strain and the defect concentration. These are both known factors influencing the dielectric properties of thin films. Reflection high energy electron diffraction (RHEED) in combination with interval pulsed laser deposition (PLD) has been used to achieve a two dimensional, layer-by-layer growth mode. Crucial to this was the deposition of a unit-cell thick titanium dioxide buffer layer on the surface, the deposition of which was also controlled by RHEED. The growth mode and microstructure of films grown using standard PLD with and without the buffer layer and films grown by interval PLD with and without the buffer layer have been compared by analysis of the RHEED data and transmission electron microscopy. This is the first time layer-by-layer growth has been achieved in this highly-mismatched epitaxial systems. The results point the way towards control of defects in oxide thin films from which microstructure-property relationships may be more clearly determined.

Download or read book Handbook of Laser Micro and Nano Engineering written by KOJI SUGIOKA. and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook provides a comprehensive review of the entire field of laser micro and nano processing, including not only a detailed introduction to individual laser processing techniques but also the fundamentals of laser-matter interaction and lasers, optics, equipment, diagnostics, as well as monitoring and measurement techniques for laser processing. Consisting of 11 sections, each composed of 4 to 6 chapters written by leading experts in the relevant field. Each main part of the handbook is supervised by its own part editor(s) so that high-quality content as well as completeness are assured. The book provides essential scientific and technical information to researchers and engineers already working in the field as well as students and young scientists planning to work in the area in the future. Lasers found application in materials processing practically since their invention in 1960, and are currently used widely in manufacturing. The main driving force behind this fact is that the lasers can provide unique solutions in material processing with high quality, high efficiency, high flexibility, high resolution, versatility and low environmental load. Macro-processing based on thermal process using infrared lasers such as CO2 lasers has been the mainstream in the early stages, while research and development of micro- and nano-processing are becoming increasingly more active as short wavelength and/or short pulse width lasers have been developed. In particular, recent advances in ultrafast lasers have opened up a new avenue to laser material processing due to the capabilities of ultrahigh precision micro- and nanofabrication of diverse materials. This handbook is the first book covering the basics, the state-of-the-art and important applications of the dynamic and rapidly expanding discipline of laser micro- and nanoengineering. This comprehensive source makes readers familiar with a broad spectrum of approaches to solve all relevant problems in science and technology. This handbook is the ultimate desk reference for all people working in the field.

Download or read book Piezoelectric Dielectric and Ferroelectric Thin Films on Metal Substrates for Microelectronic Applications written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this research has been to demonstrate the possibility of integrating piezoelectric, dielectric and ferroelectric- lead and barium based oxide thin films and PVDF polymer on flexible metal substrates for microelectronic applications. Investigations on the key processing parameters and properties relationship for lead zirconate titanate (PZT, 52D 8) and barium zirconate titanate (BZT, 35D 5) based thin films on Cu foils were performed and studied. The impact of the oxygen partial pressure on the electrical properties of PZT and BZT thin films during processing has been explored, and demonstrated that high quality films and interfaces can be achieved through control of the pO2 within a window predicted by thermodynamic stability considerations. It should be noted that the high temperature processing of barium based ferroelectric oxides can be processed on Cu foils in a wider window of pO2 compared to that of processing lead based ferroelectric oxides. Also, the high volatile nature of lead makes the processing of lead based ferroelectric oxides difficult. Considering these issues, this work shows the processing technique undertaken to achieve high quality barium and lead based oxide thin films on Cu foils. The demonstration has broad implications, opening up the possibility of the use of low cost, high conductivity copper electrodes for a range of Pb-based and Ba-based perovskite materials, including PZT films in embedded printed circuit board applications for capacitors, varactors, and sensors; multilayer PZT piezoelectric stacks; and multilayer lead magnesium niobate-lead titanate-based dielectric and electrostrictive devices. In the case of ferroelectric PZT films on Cu foil, the capacitors do not fatigue upon repeated switching like those with Pt noble metal electrodes. Instead they appear to be fatigue-resistant like ferroelectric capacitors with oxide electrodes. This may have implications for ferroelectric nonvolatile memories. The eff.