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Book Atomic Layer Deposition of Epitaxial Perovskites for Electronic and Photonic Applications

Download or read book Atomic Layer Deposition of Epitaxial Perovskites for Electronic and Photonic Applications written by Edward Lawrence Lin and published by . This book was released on 2018 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research focuses on growth of ferroelectric and conductive perovskite oxides for both electronic and photonic applications. The advancement of computing technologies requires new device architectures, new materials, and new processing techniques. Perovskite class oxides, which have the general formula of ABO3, possess various types of properties. The ability to grow perovskite oxides epitaxially on Si and Ge(001) single crystals provides an opportunity for incorporating various properties of perovskite onto semiconductor devices. In particular, barium titanate (BaTiO3, BTO) is ferroelectric enabling opportunities in reducing transistor power consumption and fabricating photonic devices. The advancement in growing epitaxial perovskite oxides on Si(001) with a strontium titanate (SrTiO3, STO) buffer layer via atomic layer deposition (ALD) shows the promise of using ALD to integrate perovskite properties into semiconductor materials. In order to realize the benefit brought by BTO, BTO films deposited by ALD need to exhibit ferroelectric polarization. This work initially focuses on ALD growth of BTO on Ge(001) and STO-buffered Si(001) single crystal substrates. Ferroelectric polarization was observed on the BTO films deposited on STO-buffered Si(001) substrates. The c-axis direction, which is the direction of BTO ferroelectric polarization, of BTO films with thickness up to 66 nm can be controlled by adjusting post-deposition annealing parameters. Ferroelectric switching of BTO on STO-buffered Si(001) in out- of-plane and in-plane directions were demonstrated by piezoresponse force microscopy and electro-optic measurement, respectively. Another part of this work concerns the mismatch between the range of BTO polarization and the polarization range needed to switch Si transistor channels. One proposal to address the mismatch is to introduce a thin conductive layer to attenuate BTO polarization. An MBE-ALD approach was developed to grow the conductive La:STO layer between a ferroelectric BTO film and the Si(001) substrate. Capacitance-voltage measurements of the BTO/La:STO film grown on STO-buffered Si(001) demonstrate attenuation of an externally applied electric field by La:STO, which is a result of the La:STO film conductivity. Lastly, this work explores the possibility of selective growth of BTO. Pattern transfer of the ALD grown film was observed by atomic force microscopy. The patterned film crystallizes after annealing the film in vacuum to the temperature of 800 °C.

Book Thin Films On Silicon  Electronic And Photonic Applications

Download or read book Thin Films On Silicon Electronic And Photonic Applications written by Vijay Narayanan and published by World Scientific. This book was released on 2016-08-15 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a broad overview of the fundamental materials science of thin films that use silicon as an active substrate or passive template, with an emphasis on opportunities and challenges for practical applications in electronics and photonics. It covers three materials classes on silicon: Semiconductors such as undoped and doped Si and SiGe, SiC, GaN, and III-V arsenides and phosphides; dielectrics including silicon nitride and high-k, low-k, and electro-optically active oxides; and metals, in particular silicide alloys. The impact of film growth and integration on physical, electrical, and optical properties, and ultimately device performance, is highlighted.

Book Crystalline Perovskite Epitaxial Growth on Germanium  001  by Atomic Layer Deposition

Download or read book Crystalline Perovskite Epitaxial Growth on Germanium 001 by Atomic Layer Deposition written by Shen Hu (Ph. D.) and published by . This book was released on 2017 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystalline perovskites (ABO3) have aroused widespread attention in material science due to their multiple properties. This research uses atomic layer deposition (ALD) to achieve perovskite oxides (ABO3) deposition on Ge (001) for gate oxide applications in microelectronics devices. In particular, this work is mainly focused on the study of crystalline Sr-based perovskites SrMO3, where M = Ti, Zr, Hf. In this research work, the mechanism for the initial growth of perovskites on Ge by ALD has been studied. High resolution scanning transmission electron microscopy (STEM) images have shown that both of molecular beam epitaxy (MBE)-grown BaTiO3 films and ALD-grown SrHfO3 films have the same interface structure, which has a 2×1 periodicity and with the alkaline earth metal (AEM) atoms between the Ge dimer rows. This result indicates that the ALD growth proceeds by forming the same Zintl-template layer that is purposely formed in MBE through formation of a 0.5-monolayer (ML) exposure to the AEM. The in situ XPS analysis has shown the same surface core level shift (SCLS) behavior results from half-cycle Sr or Ba precursor dosing on a bare Ge (001) surface as is observed following 0.5 -ML Sr or Ba exposure on Ge by MBE. These observations support the conclusion drawn from the STEM images. Based on the previous study of SrTiO3 (STO) and SrHfO3 (SHO) on Ge (001), there is a trade-off between dielectric constant and leakage current in STO and SHO. This research has also studied SrHf[subscript x]Ti1−[subscript x]O3 (SHTO) films with different Hf content x to see how composition and lattice constant affected the crystallization behavior. Crystalline SrZrO3 films have also been deposited by ALD on Ge. The C-V and I-V measurements indicate that the SrZrO3 yield the best results for dielectric properties compared to STO, SHO and SHTO. A new combined approach of oxygen plasma pre-treatment, Zintl template formation and atomic deuterium post treatment has been applied on this work to minimize the interface trap density, which has achieved 8.56×1011cm−2eV−1.

Book Synthesis and Properties of Ferroelectric Perovskite Oxide Thin Films

Download or read book Synthesis and Properties of Ferroelectric Perovskite Oxide Thin Films written by Andrei Akbasheu and published by . This book was released on 2015 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: The growth of oxide thin films has long been of great interested for materials scientists for the application in advanced technologies such as nanoelectronics, photovoltaics and sensors. Atomic layer deposition (ALD) is known for being a non-expensive, low-vacuum and low-temperature deposition method able to conformally coat even high-aspect-ratio materials and structures. ALD has been mainly applied to prepare binary oxides such as ZnO and TiO2, and the synthesis of functional complex oxides such as BiFeO3 and CoFe2O4 has little been studied. In the first part of this work, the application of ALD to the preparation of complex oxide thin films based on the Bi-Fe-O system is explored. The important aspects of the ALD approach such as (a) the growth of amorphous Bi-Fe-O by ALD, (b) the epitaxial crystallization of the multiferroic perovskite BiFeO3 films on different substrates, (c) appearance of impurity phases in the films are addressed. Ultimately, the dissertation aims at dispelling the widely held notion that atomic layer deposition is not appropriate for attaining high-quality chemically complex oxide films in the epitaxial form, demonstrating the applicability as an inexpensive, facile, and highly scalable route. The second part of this work is devoted to the preparation and characterization of new ferroelectric thin films as photovoltaic materials. Large optical band gaps of ferroelectric oxides make the optical absorption impractical for solar cell applications. Recently a new strategy for band gap lowering by doping the perovskite KNbO3 with Ba on the A-site and Ni on the B-site resulting in the generation of Ni2+-O vacancy pairs has been shown to significantly increase the optical absorption without loss of ferroelectricity. Using pulsed laser deposition, the synthesis approach to thin films of these new oxides was developed despite significant challenges for the stoichiometry control. The chemical doping approach to the reduction of the band gap was extended to produce new visible-light-absorbing ferroelectric thin films in another perovskite oxide. These materials showed a switchable photovoltaic effect under the visible light illumination along with the retention of the ferroelectric order. This dissertation demonstrates the feasibility of thin film deposition of aforementioned doped ferroelectric oxide perovskites and their ferroelectric photovoltaic properties, which can be extended to other ferroelectric oxides, and provide important information on the synthesis of such materials as thin films.

Book Thin Film Growth and Deposition of Functional Perovskite Oxides

Download or read book Thin Film Growth and Deposition of Functional Perovskite Oxides written by Bryce Isaiah Edmondson and published by . This book was released on 2019 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research documented in this work focuses on the growth and deposition of thin film perovskite oxides for their electronic and photonic functionalities. The ever increasing demand for faster electronic devices, particularly in the realm of micro and nanoelectronics, is requiring diversification of the materials used in typical semiconductor-based integrated circuits. Metal oxides, particularly those in the perovskite family of materials, offers a wide range of functionalities that can both increase device performance and add new capabilities such as optical interconnects. The process in which perovskite oxide thin films are deposited and integrated with one another and conventional semiconductors can have many effects on the properties of the resulting device. This work explores these effects in the context of BaTiO3 (BTO) and Ba [subscript x] Sr1- [subscript x] TiO3 (BST) second order nonlinear optical effects, which includes second harmonic generation (SHG) and the linear electro-optic effect (Pockels effect). The work also studies the growth effects on the apparent interfacial conductivity of LaTiO3/SrTiO3 (LTO/STO) heterostructures. BTO thin films grown epitaxially on STO(001) by molecular beam epitaxy (MBE) experience strain relaxation due to misfit dislocations for increasing thickness while epitaxial BST thin films remain strained at equivalent thicknesses due to the smaller lattice mismatch. These strained BST films exhibit larger second harmonic generation than relaxed BTO films, for particular compositions, suggesting that the epitaxial strain enhances their polarization and second order nonlinear susceptibility beyond what is capable in equivalently thick, relaxed BTO films. We also explore the deposition of BTO and BST thin films by a chemical solution method under atmospheric conditions. The films are epitaxial with STO(001) template layers prepared by MBE on Si(001) wafers. Presence of the Pockels effect is confirmed in the films, although optical hysteresis and remanent polarization is not observed owing to the films' small (10-100 nm) grain size, structural defects, and residual tensile stress. Effective Pockels coefficients decrease monotonically with decreasing Ba composition. Non-zero Pockels response is observed in even Sr-rich films, which is explained by the tensile stress that deforms the normally cubic crystal structure into a non-centrosymmetric structure. Post-deposition annealing can increase the Pockels response by approximately four times and is attributed to an increase in grain size and the elimination of structural defects. Finally, we study the effects of oxygen vacancies caused by varying MBE growth conditions of LTO thin films on STO(001) single crystals and thin STO layers on Ge(001). Electrical conductivity of the heterostructures is LTO-thickness dependent, and LTO growth on STO/Ge structures requires orders of magnitude higher partial pressures of molecular oxygen in order to achieve crystalline LTO with proper oxidation states. This is explained by the propensity of LTO to scavenge oxygen from STO during growth, which is limited in LTO/STO/Ge heterostructures, and generates many free carriers and leads to the observed conductivity of the LTO/STO systems

Book Oxide Electronics

Download or read book Oxide Electronics written by Asim K. Ray and published by John Wiley & Sons. This book was released on 2021-04-12 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oxide Electronics Multiple disciplines converge in this insightful exploration of complex metal oxides and their functions and properties Oxide Electronics delivers a broad and comprehensive exploration of complex metal oxides designed to meet the multidisciplinary needs of electrical and electronic engineers, physicists, and material scientists. The distinguished author eschews complex mathematics whenever possible and focuses on the physical and functional properties of metal oxides in each chapter. Each of the sixteen chapters featured within the book begins with an abstract and an introduction to the topic, clear explanations are presented with graphical illustrations and relevant equations throughout the book. Numerous supporting references are included, and each chapter is self-contained, making them perfect for use both as a reference and as study material. Readers will learn how and why the field of oxide electronics is a key area of research and exploitation in materials science, electrical engineering, and semiconductor physics. The book encompasses every application area where the functional and electronic properties of various genres of oxides are exploited. Readers will also learn from topics like: Thorough discussions of High-k gate oxide for silicon heterostructure MOSFET devices and semiconductor-dielectric interfaces An exploration of printable high-mobility transparent amorphous oxide semiconductors Treatments of graphene oxide electronics, magnetic oxides, ferroelectric oxides, and materials for spin electronics Examinations of the calcium aluminate binary compound, perovoksites for photovoltaics, and oxide 2Degs Analyses of various applications for oxide electronics, including data storage, microprocessors, biomedical devices, LCDs, photovoltaic cells, TFTs, and sensors Suitable for researchers in semiconductor technology or working in materials science, electrical engineering, and physics, Oxide Electronics will also earn a place in the libraries of private industry researchers like device engineers working on electronic applications of oxide electronics. Engineers working on photovoltaics, sensors, or consumer electronics will also benefit from this book.

Book Crystal Structure Electronic and Optical Properties of Epitaxial Alkaline Earth Niobate Thin Films

Download or read book Crystal Structure Electronic and Optical Properties of Epitaxial Alkaline Earth Niobate Thin Films written by Dongyang Wan and published by Springer. This book was released on 2017-09-18 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: This impressive thesis offers a comprehensive scientific study of the alkaline earth niobates and describes their nonlinear optical properties for the first time. It explores the crystal structure, electrical properties, optical absorption properties, hot carrier dynamics, nonlinear optical property and strain-induced metal to insulator transition of alkaline earth niobates using advanced experimental techniques. These alkaline earth niobates can have a strong plasmon resonance in the visible range due to their large carrier density, and this unique property gives rise to the emergent phenomenon of photocatalysis and nonlinear optical properties. This series of intrinsic plasmonic materials based on niobates, can be used as a photocatalyst to split water under sunlight, a novel saturable absorber in the high-power ultrashort pulsed laser system, and as a sensor in microelectromechanical systems.

Book Electrical   Electronics Abstracts

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2092 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Chemical Vapor Transport Reactions

Download or read book Chemical Vapor Transport Reactions written by Michael Binnewies and published by Walter de Gruyter. This book was released on 2012-08-31 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive handbook covers the diverse aspects of chemical vapor transport reactions from basic research to important practical applications. The book begins with an overview of models for chemical vapor transport reactions and then proceeds to treat the specific chemical transport reactions for the elements, halides, oxides, sulfides, selenides, tellurides, pnictides, among others. Aspects of transport from intermetallic phases, the stability of gas particles, thermodynamic data, modeling software and laboratory techniques are also covered. Selected experiments using chemical vapor transport reactions round out the work, making this book a useful reference for researchers and instructors in solid state and inorganic chemistry.

Book Solution Processable Components for Organic Electronic Devices

Download or read book Solution Processable Components for Organic Electronic Devices written by Beata Luszczynska and published by John Wiley & Sons. This book was released on 2019-09-16 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides first-hand insights into advanced fabrication techniques for solution processable organic electronics materials and devices The field of printable organic electronics has emerged as a technology which plays a major role in materials science research and development. Printable organic electronics soon compete with, and for specific applications can even outpace, conventional semiconductor devices in terms of performance, cost, and versatility. Printing techniques allow for large-scale fabrication of organic electronic components and functional devices for use as wearable electronics, health-care sensors, Internet of Things, monitoring of environment pollution and many others, yet-to-be-conceived applications. The first part of Solution-Processable Components for Organic Electronic Devices covers the synthesis of: soluble conjugated polymers; solution-processable nanoparticles of inorganic semiconductors; high-k nanoparticles by means of controlled radical polymerization; advanced blending techniques yielding novel materials with extraordinary properties. The book also discusses photogeneration of charge carriers in nanostructured bulk heterojunctions and charge carrier transport in multicomponent materials such as composites and nanocomposites as well as photovoltaic devices modelling. The second part of the book is devoted to organic electronic devices, such as field effect transistors, light emitting diodes, photovoltaics, photodiodes and electronic memory devices which can be produced by solution-based methods, including printing and roll-to-roll manufacturing. The book provides in-depth knowledge for experienced researchers and for those entering the field. It comprises 12 chapters focused on: ? novel organic electronics components synthesis and solution-based processing techniques ? advanced analysis of mechanisms governing charge carrier generation and transport in organic semiconductors and devices ? fabrication techniques and characterization methods of organic electronic devices Providing coverage of the state of the art of organic electronics, Solution-Processable Components for Organic Electronic Devices is an excellent book for materials scientists, applied physicists, engineering scientists, and those working in the electronics industry.

Book Hybrid Organic Inorganic Perovskites

Download or read book Hybrid Organic Inorganic Perovskites written by Li Wei and published by John Wiley & Sons. This book was released on 2020-10-19 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybrid organic-inorganic perovskites (HOIPs) have attracted substantial interest due to their chemical variability, structural diversity and favorable physical properties the past decade. This materials class encompasses other important families such as formates, azides, dicyanamides, cyanides and dicyanometallates. The book summarizes the chemical variability and structural diversity of all known hybrid organic-inorganic perovskites subclasses including halides, azides, formates, dicyanamides, cyanides and dicyanometallates. It also presents a comprehensive account of their intriguing physical properties, including photovoltaic, optoelectronic, dielectric, magnetic, ferroelectric, ferroelastic and multiferroic properties. Moreover, the current challenges and future opportunities in this exciting field are also been discussed. This timely book shows the readers a complete landscape of hybrid organic-inorganic pervoskites and associated multifuctionalities.

Book Perovskite Photovoltaics

Download or read book Perovskite Photovoltaics written by Aparna Thankappan and published by Academic Press. This book was released on 2018-06-29 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perovskite Photovoltaics: Basic to Advanced Concepts and Implementation examines the emergence of perovskite photovoltaics, associated challenges and opportunities, and how to achieve broader development. Consolidating developments in perovskite photovoltaics, including recent progress solar cells, this text also highlights advances and the research necessary for sustaining energy. Addressing different photovoltaics fields with tailored content for what makes perovskite solar cells suitable, and including commercialization examples of large-scale perovskite solar technology. The book also contains a detailed analysis of the implementation and economic viability of perovskite solar cells, highlighting what photovoltaic devices need to be generated by low cost, non-toxic, earth abundant materials using environmentally scalable processes. This book is a valuable resource engineers, scientists and researchers, and all those who wish to broaden their knowledge on flexible perovskite solar cells. Includes contributions by leading solar cell academics, industrialists, researchers and institutions across the globe Addresses different photovoltaics fields with tailored content for what makes perovskite solar cells different Provides commercialization examples of large-scale perovskite solar technology, giving users detailed analysis on the implementation, technical challenges and economic viability of perovskite solar cells

Book Ceramic Abstracts

Download or read book Ceramic Abstracts written by and published by . This book was released on 1998 with total page 1040 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Multifunctional Oxide Heterostructures

Download or read book Multifunctional Oxide Heterostructures written by Evgeny Y. Tsymbal and published by OUP Oxford. This book was released on 2012-08-30 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is devoted to the rapidly developing field of oxide thin-films and heterostructures. Oxide materials combined with atomic-scale precision in a heterostructure exhibit an abundance of macroscopic physical properties involving the strong coupling between the electronic, spin, and structural degrees of freedom, and the interplay between magnetism, ferroelectricity, and conductivity. Recent advances in thin-film deposition and characterization techniques made possible the experimental realization of such oxide heterostructures, promising novel functionalities and device concepts. The book consists of chapters on some of the key innovations in the field over recent years, including strongly correlated oxide heterostructures, magnetoelectric coupling and multiferroic materials, thermoelectric phenomena, and two-dimensional electron gases at oxide interfaces. The book covers the core principles, describes experimental approaches to fabricate and characterize oxide heterostructures, demonstrates new functional properties of these materials, and provides an overview of novel applications.

Book Tailored Thin Coatings for Corrosion Inhibition Using a Molecular Approach

Download or read book Tailored Thin Coatings for Corrosion Inhibition Using a Molecular Approach written by Simo Olavi Pehkonen and published by Academic Press. This book was released on 2018-08-25 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tailored Thin Coatings for Corrosion Inhibition Using a Molecular Approach discusses the fundamentals and applications of various thin coatings for the inhibition of fouling and corrosion from a molecular perspective. It provides the reader with a fundamental understanding of why certain coatings perform better than others in a given environment. Surface analytical and electrochemical techniques in understanding the coating performance are emphasized throughout the book, providing readers with a useful reference on how to pursue a systematic corrosion inhibitor R&D program that involves the testing of coating performance using various, currently available, state-of-the-art laboratory techniques. Wherever relevant, environmental considerations of the discussed coatings’ technologies are highlighted and discussed, with current and upcoming regulatory trends put forth by different governmental organizations. Provides atomic and molecular level understanding of tailored thin coatings for corrosion inhibition Discusses key steps in corrosion, including the attachment of harmful substances to surfaces, the fouling of surfaces, and the initiation and propagation of corrosion on surfaces Written by leading experts in the field

Book Handbook of Crystal Growth

Download or read book Handbook of Crystal Growth written by Peter Rudolph and published by Elsevier. This book was released on 2014-11-04 with total page 1420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vol 2A: Basic TechnologiesHandbook of Crystal Growth, Second Edition Volume IIA (Basic Technologies) presents basic growth technologies and modern crystal cutting methods. Particularly, the methodical fundamentals and development of technology in the field of bulk crystallization on both industrial and research scales are explored. After an introductory chapter on the formation of minerals, ruling historically the basic crystal formation parameters, advanced basic technologies from melt, solution, and vapour being applied for research and production of the today most important materials, like silicon, semiconductor compounds and oxides are presented in detail. The interdisciplinary and general importance of crystal growth for human live are illustrated.Vol 2B: Growth Mechanisms and DynamicsHandbook of Crystal Growth, Second Edition Volume IIB (Growth Mechanisms and Dynamics) deals with characteristic mechanisms and dynamics accompanying each bulk crystal growth method discussed in Volume IIA. Before the atoms or molecules pass over from a position in the fluid medium (gas, melt or solution) to their place in the crystalline face they must be transported in the fluid over macroscopic distances by diffusion, buoyancy-driven convection, surface-tension-driven convection, and forced convection (rotation, acceleration, vibration, magnetic mixing). Further, the heat of fusion and the part carried by the species on their way to the crystal by conductive and convective transport must be dissipated in the solid phase by well-organized thermal conduction and radiation to maintain a stable propagating interface. Additionally, segregation and capillary phenomena play a decisional role for chemical composition and crystal shaping, respectively. Today, the increase of high-quality crystal yield, its size enlargement and reproducibility are imperative conditions to match the strong economy. Volume 2A Presents the status and future of Czochralski and float zone growth of dislocation-free silicon Examines directional solidification of silicon ingots for photovoltaics, vertical gradient freeze of GaAs, CdTe for HF electronics and IR imaging as well as antiferromagnetic compounds and super alloys for turbine blades Focuses on growth of dielectric and conducting oxide crystals for lasers and non-linear optics Topics on hydrothermal, flux and vapour phase growth of III-nitrides, silicon carbide and diamond are explored Volume 2B Explores capillarity control of the crystal shape at the growth from the melt Highlights modeling of heat and mass transport dynamics Discusses control of convective melt processes by magnetic fields and vibration measures Includes imperative information on the segregation phenomenon and validation of compositional homogeneity Examines crystal defect generation mechanisms and their controllability Illustrates proper automation modes for ensuring constant crystal growth process Exhibits fundamentals of solution growth, gel growth of protein crystals, growth of superconductor materials and mass crystallization for food and pharmaceutical industries

Book Thin Films on Silicon

Download or read book Thin Films on Silicon written by Vijay Narayanan and published by . This book was released on 2016 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This volume provides a broad overview of the fundamental materials science of thin films that use silicon as an active substrate or passive template, with an emphasis on opportunities and challenges for practical applications in electronics and photonics. It covers three materials classes on silicon: Semiconductors such as undoped and doped Si and SiGe, SiC, GaN, and III-V arsenides and phosphides; dielectrics including silicon nitride and high-k, low-k, and electro-optically active oxides; and metals, in particular silicide alloys. The impact of film growth and integration on physical, electrical, and optical properties, and ultimately device performance, is highlighted."--Publisher's website.