Download or read book Microwave Properties of Barium Strontium Titanate Thin Films written by Yin-lai Cheng and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural and Electrical Properties of Barium Strontium Titanate Thin Films for Tunable Microwave Applications written by Sriraj G. Manavalan and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: The dependence of dielectric permittivity on the applied electric field, high dielectric constant and low cost makes barium strontium titanate (BST) a promising ferroelectric material for applications in tunable microwave devices. High tunability and low dielectric loss is desired for tunable microwave devices. The primary objective of this research was to optimize the tunability and dielectric loss of BST thin films at microwave frequencies with different deposition techniques. Ba0.5Sr0.5TiO3 thin films were grown on Pt/TiO2/SiO2/Si, by pulsed laser deposition (PLD) and sputtering. Parallel plate capacitor structures were designed using ADS and fabricated. The microstructural and phase analysis of the BST films were performed using X-ray diffraction (XRD) method. The diffraction patterns are attributed to cubic (perovskite) crystal system. The analysis of surface morphology was done using atomic force microscopy.
Download or read book Dielectric Properties of Barium Strontium Titanate BST Thin Films and Phase Shifters Based on BST Thin Films written by Xiaoyuan Zhou and published by . This book was released on 2008 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nano Crystalline and Thin Film Magnetic Oxides written by Ivan Nedkov and published by Elsevier. This book was released on 1999-09-30 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop on Ferrimagnetic Nano-crystalline and Thin Film Magnetooptical and Microwave Materials, Sozopol, Bulgaria, 27 September - 3 October, 1998
Download or read book Strain and Thickness on the Microwave Properties of BST Thin Films written by Jeffrey A. Bellotti and published by . This book was released on 2003 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Properties of Nanoscale Barium Strontium Titanate Microwave Varactors written by Tony S. Price and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Barium strontium titanate thin film varactors have been widely investigated for the purpose of creating tunable front-ends for RF and microwave systems. There is an abundance of literature observing the capacitance-voltage behavior and methods on improving tunability. However, there is a lack of thorough investigations on the nonlinear behavior, specifically the third order intermodulation distortion, and the parameters that impact it. There is also a research void that needs to be filled for nanoscale barium strontium titanate varactors as nanotechnology becomes increasingly prevalent in the design of RF and microwave components. This work aims to advance the understanding of nonlinear properties of barium strontium titanate varactors. Temperature and voltage impacts on the third order intermodulation distortion products of BST varactors are observed by two-tone measurements. The material properties of the films are correlated with the nonlinear behavior of the varactors. Additionally, size reduction capabilities are shown by fabricating planar barium strontium titanate interdigital varactors with nanoscale size gaps between the electrodes. Modeling techniques are also investigated.
Download or read book Barium Strontium Titanate Thin Film Base Multi Layer Structures for Microwave Application written by Kumaravinothan N. Sanmugaratna Sarma and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ferroelectrics in Microwave Devices Circuits and Systems written by Spartak Gevorgian and published by Springer Science & Business Media. This book was released on 2009-05-30 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today’s wireless communications and information systems are heavily based on microwave technology. Current trends indicate that in the future along with - crowaves, the millimeter wave and Terahertz technologies will be used to meet the growing bandwidth and overall performance requirements. Moreover, motivated by the needs of the society, new industry sectors are gaining ground; such as wi- less sensor networks, safety and security systems, automotive, medical, envir- mental/food monitoring, radio tags etc. Furthermore, the progress and the pr- lems in the modern society indicate that in the future these systems have to be more user/consumer friendly, i. e. adaptable, reconfigurable and cost effective. The mobile phone is a typical example which today is much more than just a phone; it includes a range of new functionalities such as Internet, GPS, TV, etc. To handle, in a cost effective way, all available and new future standards, the growing n- ber of the channels and bandwidth both the mobile handsets and the associated systems have to be agile (adaptable/reconfigurable). The complex societal needs have initiated considerable activities in the field of cognitive and software defined radios and triggered extensive research in adequate components and technology platforms. To meet the stringent requirements of these systems, especially in ag- ity and cost, new components with enhanced performances and new functionalities are needed. In this sense the components based on ferroelectrics have greater - tential and already are gaining ground.
Download or read book Ferroelectrics written by Mickaël Lallart and published by BoD – Books on Demand. This book was released on 2011-08-24 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferroelectric materials have been and still are widely used in many applications, that have moved from sonar towards breakthrough technologies such as memories or optical devices. This book is a part of a four volume collection (covering material aspects, physical effects, characterization and modeling, and applications) and focuses on ways to obtain high-quality materials exhibiting large ferroelectric activity. The book covers the aspect of material synthesis and growth, doping and composites, lead-free devices, and thin film synthesis. The aim of this book is to provide an up-to-date review of recent scientific findings and recent advances in the field of ferroelectric materials, allowing a deep understanding of the material aspects of ferroelectricity.
Download or read book A Systematic Investigation of Strain stress Effect on the Dielectric Properties of Barium Strontium Titanate Thin Films written by 路勝博 and published by . This book was released on 2010 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Barium Strontium Titanate Films for Tunable Microwave and Acoustic Wave Applications written by Venkataramanan Gurumurthy and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: The composition-dependent Curie temperature and bias-dependant dielectric permittivity of Barium Strontium Titanate (BST) makes it very attractive for tunable application in the RF/Microwave regime. In this research work, the performance of BST varactors fabricated on the conventional Pt/Ti/SiO2/Si bottom electrode stack were compared with those fabricated using chemical vapor deposited Nanocrystalline Diamond (NCD) as the diffusion barrier layer instead of SiO2. The varactors fabricated on NCD films displayed much better symmetry in capacitance-voltage behavior and better overall quality factors than varactors fabricated on SiO2. The improvement in performance can be attributed to existence of stable interfaces in the devices fabricated on NCD which reduced the bottom electrode losses at high frequencies. The SiO2 based BST varactors on the other hand displayed better reliability and breakdown fields. The main purpose of this research work is to develop a robust Metal Insulator Metal (MIM) structure to achieve better all round performance of BST varactors. In the second part of this research work, the prospect of developing diamond based layered Surface Acoustic Wave (SAW) devices using Ba0.8Sr0.2TiO3 as the piezoelectric layer is investigated. Structural characterization of BST thin films deposited on Si/NCD/Pt and Si/SiO2/Ti/Pt stack were performed using X-Ray Diffraction (XRD) and Atomic Force Microscopy (AFM). Cross-sectional studies on the two stacks were performed using Scanning Electron Microscopy (SEM). X-Ray Mapping (XRM) was then done to ascertain the quality of the interfaces and to check for interdiffusion between layers. MIM structures in the Coplanar Waveguide (CPW) configuration were fabricated using conventional lithography and etching techniques for high frequency measurements. The performance of the fabricated varactors was characterized from 100 MHz to 1 GHz. For the SAW application, structural characterization of Ba0.8Sr0.2TiO3 on Chemical Vapor Deposited (CVD) diamond was done and the deposition procedure was optimized to obtain thick BST films. SAW bandpass filters and resonators were designed wherein the device geometry was varied over a wide range in order to characterize the variation in device performance with geometry. Finally interdigital capacitor structures were fabricated and used for conducting Curie temperature measurements on the deposited BST films in order to determine the operation range of the deposited BST films.
Download or read book Microstrip Filters for RF Microwave Applications written by Jia-Sheng Hong and published by John Wiley & Sons. This book was released on 2011-01-06 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first edition of “Microstrip Filters for RF/Microwave Applications” was published in 2001. Over the years the book has been well received and is used extensively in both academia and industry by microwave researchers and engineers. From its inception as a manuscript the book is almost 8 years old. While the fundamentals of filter circuits have not changed, further innovations in filter realizations and other applications have occurred with changes in the technology and use of new fabrication processes, such as the recent advances in RF MEMS and ferroelectric films for tunable filters; the use of liquid crystal polymer (LCP) substrates for multilayer circuits, as well as the new filters for dual-band, multi-band and ultra wideband (UWB) applications. Although the microstrip filter remains as the main transmission line medium for these new developments, there has been a new trend of using combined planar transmission line structures such as co-planar waveguide (CPW) and slotted ground structures for novel physical implementations beyond the single layer in order to achieve filter miniaturization and better performance. Also, over the years, practitioners have suggested topics that should be added for completeness, or deleted in some cases, as they were not very useful in practice. In view of the above, the authors are proposing a revised version of the “Microstrip Filters for RF/Microwave Applications” text and a slightly changed book title of “Planar Filters for RF/Microwave Applications” to reflect the aforementioned trends in the revised book.
Download or read book Microstructure and Nonstoichiometry of Barium Strontium Titanate Thin Films for Dram Applications written by and published by . This book was released on 1999 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper we investigate the microstructural accommodation of nonstoichiometry in (Ba(subscript x)Sr{sub 1-x}Ti{sub 1+y}O{sub 3+z}) thin films grown by chemical vapor deposition. Films with three different (Ba+Sr)/Ti ratios of 49/51 (y=0.04 in the notation of the formula above), of 48/52 (y=0.08) and of 46.5/53.5 (y=O.15), were studied. High-resolution electron microscopy is used to study the microstructure of the BST films. High-spatial resolution electron energy-loss spectroscopy (EELS) is used to reveal changes in chemistry and local atomic environment both at grain boundaries and within grains as a function of titanium excess. We find an amorphous phase at the grain boundaries and grain boundary segregation of excess titanium in the samples with y=0.15. In addition, EELS is also used to show that excess titanium is being partially accommodated in the grain interior. Implications for the film electrical and dielectric properties are outlined.
Download or read book Ceramic Integration and Joining Technologies written by Mrityunjay Singh and published by John Wiley & Sons. This book was released on 2011-10-11 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book joins and integrates ceramics and ceramic-based materials in various sectors of technology. A major imperative is to extract scientific information on joining and integration response of real, as well as model, material systems currently in a developmental stage. This book envisions integration in its broadest sense as a fundamental enabling technology at multiple length scales that span the macro, millimeter, micrometer and nanometer ranges. Consequently, the book addresses integration issues in such diverse areas as space power and propulsion, thermoelectric power generation, solar energy, micro-electro-mechanical systems (MEMS), solid oxide fuel cells (SOFC), multi-chip modules, prosthetic devices, and implanted biosensors and stimulators. The engineering challenge of designing and manufacturing complex structural, functional, and smart components and devices for the above applications from smaller, geometrically simpler units requires innovative development of new integration technology and skillful adaptation of existing technology.
Download or read book Study of Barium Strontium Zirconate Titanate Thin Films and Their Microwave Device Applications written by Ngai-yui Chan and published by . This book was released on 2010 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Processing Science of Barium Titanate written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Barium titanate and barium strontium titanate thin films were deposited on base metal foils via chemical solution deposition and radio frequency magnetron sputtering. The films were processed at elevated temperatures for densification and crystallization. Two unifying research goals underpin all experiments: 1) To improve our fundamental understanding of complex oxide processing science, and 2) to translate those improvements into materials with superior structural and electrical properties. The relationships linking dielectric response, grain size, and thermal budget for sputtered barium strontium titanate were illustrated. (Ba0.6Sr0.4)TiO3 films were sputtered on nickel foils at temperatures ranging between 100-400 Ã'°C. After the top electrode deposition, the films were co-fired at 900 Ã'°C for densification and crystallization. The dielectric properties were observed to improve with increasing sputter temperature reaching a permittivity of 1800, a tunability of 10:1, and a loss tangent of less than 0.015 for the sample sputtered at 400 Ã'°C. The data can be understood using a brick wall model incorporating a high permittivity grain interior with low permittivity grain boundary. However, this high permittivity value was achieved at a grain size of 80 nm, which is typically associated with strong suppression of the dielectric response. These results clearly show that conventional models that parameterize permittivity with crystal diameter or film thickness alone are insufficiently sophisticated. Better models are needed that incorporate the influence of microstructure and crystal structure. This thesis next explores the ability to tune microstructure and properties of chemically solution deposited BaTiO3 thin films by modulation of heat treatment thermal profiles and firing atmosphere composition. Barium titanate films were deposited on copper foils using hybrid-chelate chemistries. An in-situ gas analysis process was developed to probe the organic removal and.
Download or read book Growth and Properties of Barium Strontium Titanate Thin Films and Multilayer Stacks written by D. O'Neill and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
