This thesis describes a new approach to the construction of "solar cells." Following nature's example, this approach has the goal to find a biomimetic self-assembling dye, whose aggregates can mimic the natural light-harvesting system of special photosynthetic active bacteria. The thesis investigates methods to control the self-assembly such that suitable dye aggregates are formed with high internal order and size-confinement. The dye aggregates can be implemented into a new type of "solar cells," designed to combine the advantages of "hybrid solar cells" and "solid-state dye-sensitized solar cells" (ss-DSSCs): dye aggregate solar cells (DASCs). This book describes the construction and first tests of a prototype for DASCs on the basis of the investigated dye aggregates. The described approach has the advantage that it will enable to build up a light-harvesting system fully synthetically in large scale in order to realize low-cost, light-weight and environmentally friendly solar cells - a worthwhile goal towards the exploitation of clean energy from sunlight.

Branch-and-bound search has been known for a long time and has been widely used in solving a variety of problems in computer-aided design (CAD) and many important optimization problems. In many applications, the classic branch-and-bound search methods perform duplications of computations, or rely on the search decision trees which keep track of the branch-and-bound search processes. In CAD and many other technical fields, the computational cost of constructing branch-and-bound search decision trees in solving large scale problems is prohibitive and duplications of computations are intolerable. Efficient branch-and-bound methods are needed to deal with today's computational challenges. Efficient branch-and-bound methods must not duplicate computations. Efficient Branch and Bound Search with Application to Computer-Aided Design describes an efficient branch-and-bound method for logic justification, which is fundamental to automatic test pattern generation (ATPG), redundancy identification, logic synthesis, minimization, verification, and other problems in CAD. The method is called justification equivalence, based on the observation that justification processes may share identical subsequent search decision sequences. With justification equivalence, duplication of computations is avoided in the dynamic branch-and-bound search process without using search decision trees. Efficient Branch and Bound Search with Application to Computer-Aided Design consists of two parts. The first part, containing the first three chapters, provides the theoretical work. The second part deals with applications, particularly ATPG for sequential circuits. This book is particularly useful to readers who are interested in the design and test of digital circuits.

This monographdeals with metastable states in amorphoussemiconductors- ma- rials which lack long-range periodicity in the atoms' positions, which are in th- modynamic nonequilibrium and which, in addition, have several metastable states. Thesestates giverise tovariouspropertiesandeffects- namelya widerangeofp- toinduced changes and high photosensitivity and X-ray sensitivity - that are unique among solid-state semiconductors.Historically, amorphousselenium and seleni- based materials have played an important role in physics and technology, and they continue to do so. In these materials there exist inherent intermediate (metastable) states, structural and electronic in origin, which lead to interesting properties and effects different from those of their crystalline counterparts. In this volume, the metastable states and related effects are investigated in depth against the background of a detailed consideration of local atomic and electronic structure, and taking into account a wide range of light-induced effects. Although the rst publications on amorphous semiconductors date back to the early 1970s, studies of metastable states in these materials had not been analyzed systematically up to now, which led to erroneous ideas, even among specialists. In the present book, experimental investigations of metastable states are reported in detail for elemental selenium and selenium-based materials.

System Test and Diagnosis is the first book on test and diagnosis at the system level, defined as any aggregation of related elements that together form an entity of sufficient complexity for which it is impractical to treat all of the elements at the lowest level of detail. The ideas presented emphasize that it is possible to diagnose complex systems efficiently. Since the notion of system is hierarchical, these ideas are applicable to all levels. The philosophy is presented in the context of a model-based approach, using the information flow model, that focuses on the information provided by the tests rather than the functions embedded in the system. Detailed algorithms are offered for evaluating system testability, performing efficient diagnosis, verifying and validating the models, and constructing an architecture for system maintenance. Several advanced algorithms, not commonly available in existing diagnosis tools, are discussed, including reasoning with inexact or uncertain test data, breaking large problems into manageable smaller problems, diagnosing systems with time sensitive information and time dependent tests and learning from experience. The book is divided into three parts. The first part provides motivation for careful development of the subject and the second part provides the tools necessary for analyzing system testability and computing diagnostic strategies. The third part presents advanced topics in diagnosis. Several case studies are provided, including a single detailed case study. Smaller case studies describe experiences from actual applications of the methods discussed. The detailed case study walks the reader through a complete analysis of a system to illustrate the concepts and describe the analyses that are possible. All case studies are based upon real systems that have been modeled for the purposes of diagnosis. System Test and Diagnosis is the culmination of nearly twelve years of research into diagnosis modeling and its applications. It is designed as a primary reference for engineers and practitioners interested in system test and diagnosis.

Gallium Arsenide technology has come of age. GaAs integrated circuits are available today as gate arrays with an operating speed in excess of one Gigabits per second. Special purpose GaAs circuits are used in optical fiber digital communications systems for the purpose of regeneration, multiplexing and switching of the optical signals. As advances in fabrication and packaging techniques are made, the operat ing speed will further increase and the cost of production will reach a point where large scale application of GaAs circuits will be economical in these and other systems where speed is paramount. This book is written for students and engineers who wish to enter into this new field of electronics for the first time and who wish to embark on a serious study of the subject of GaAs circuit design. No prior knowledge of GaAs technology is assumed though some previous experience with MOS circuit design will be helpful. A good part of the book is devoted to circuit analysis, to the extent that is possible for non linear circuits. The circuit model of the GaAs transistor is derived from first principles and analytic formulas useful in predicting the approxi mate circuit performance are also derived. Computer simulation is used throughout the book to show the expected performance and to study the effects of parameter variations."

The great interest in photonic crystals and their applications in the last 15 years is being expressed in the publishing of a large number of monographs, collections, textbooks and tutorials, where existing knowledge concerning - eration principles of photonic crystal devices and microstructured ?bers, their mathematicaldescription,well-knownandnovelapplicationsofsuchtechno- gies in photonics and optical communications are presented. They challenges authors of new books to cover the gaps still existing in the literature and highlight and popularize of already known material in a new and original manner. Authorsofthisbookbelievethatthenextsteptowardswideapplicationof photoniccrystalsisthesolutionofmanypracticalproblemsofdesignandc- putation of the speci?c photonic crystal-based devices aimed at the speci?c technicalapplication.Inordertomakethisstep,itisnecessarytoincreasethe number of practitioners who can solve such problems independently. The aim of this book is to extend the group of researchers, developers and students, who could practically use the knowledge on the physics of photonic crystals together with the knowledge and skills of independent calculation of basic characteristics of photonic crystals and modeling of various elements of - tegrated circuits and optical communication systems created on the basis of photonic crystals. The book is intended for quali?ed readers, specialists in the ?eld of optics and photonics, students of higher courses, master degree students and PhD students. As an introduction to the snopest, the book contains the basics of wave optics and radiation propagation in simple guiding media such as planar waveguides and step-index ?bers.

This book presents an in-depth discussion of the semiconductor-laser gain medium. The optical and electronic properties of semiconductors, particularly semiconductor quantum-well systems, are analzyed in detail, covering a wide variety of near-infrared systems with or without strain, as well as wide-gap materials such as the group-III nitride compounds or the II-VI materials. The important bandstructure modifications and Coulomb interaction effects are discussed, including the solution of the longstanding semiconductor laser lineshape problem. Quantitative comparisons between measured and predicted gain/absorption and refractive index spectra for a wide variety of semiconductor-laser materials enable the theoretical results to be used directly in the engineering of advanced laser and amplifier structures. A wealth of examples for many different material combinations bestow the book with quantitative and predictive value for a wide variety of applications.

Scanning Probe Lithography (SPL) describes recent advances in the field of scanning probe lithography, a high resolution patterning technique that uses a sharp tip in close proximity to a sample to pattern nanometer-scale features on the sample. SPL is capable of patterning sub-30nm features with nanometer-scale alignment registration. It is a relatively simple, inexpensive, reliable method for patterning nanometer-scale features on various substrates. It has potential applications for nanometer-scale research, for maskless semiconductor lithography, and for photomask patterning. The authors of this book have been key players in this exciting new field. Calvin Quate has been involved since the beginning in the early 1980s and leads the research time that is regarded as the foremost group in this field. Hyongsok Tom Soh and Kathryn Wilder Guarini have been the members of this group who, in the last few years, have brought about remarkable series of advances in SPM lithography. Some of these advances have been in the control of the tip which has allowed the scanning speed to be increased from mum/second to mm/second. Both non-contact and in-contact writing have been demonstrated as has controlled writing of sub-100 nm lines over large steps on the substrate surface. The engineering of a custom-designed MOSFET built into each microcantilever for individual current control is another notable achievement. Micromachined arrays of probes each with individual control have been demonstrated. One of the most intriguing new aspects is the use of directly-grown carbon nanotubes as robust, high-resolution emitters. In this book the authors concisely and authoritatively describe the historical context, the relevant inventions, and the prospects for eventual manufacturing use of this exciting new technology.

Bringing Scanning Probe Microscopy Up to Speed introduces the principles of scanning probe systems with particular emphasis on techniques for increasing speed. The authors include useful information on the characteristics and limitations of current state-of-the-art machines as well as the properties of the systems that will follow in the future. The basic approach is two-fold. First, fast scanning systems for single probes are treated and, second, systems with multiple probes operating in parallel are presented. The key components of the SPM are the mechanical microcantilever with integrated tip and the systems used to measure its deflection. In essence, the entire apparatus is devoted to moving the tip over a surface with a well-controlled force. The mechanical response of the actuator that governs the force is of the utmost importance since it determines the scanning speed. The mechanical response relates directly to the size of the actuator; smaller is faster. Traditional scanning probe microscopes rely on piezoelectric tubes of centimeter size to move the probe. In future scanning probe systems, the large actuators will be replaced with cantilevers where the actuators are integrated on the beam. These will be combined in arrays of multiple cantilevers with MEMS as the key technology for the fabrication process.

This book discusses the effects, modeling, latest results, and nanotechnology applications of rainbows that appear during channeling of charged particles in crystals and nanotubes. The authors begin with a brief review of the optical and particle rainbow effects followed by a detailed description of crystal rainbows, which appear in ion channeling in crystals, and their modeling using catastrophe theory. The effects of spatial and angular focusing of channeled ions are described, with special attention given to the applications of the former effect to subatomic microscopy. The results of a thorough study of the recent high-resolution channeling experiments performed with protons of energies between 2.0 and 0.7 MeV and a 55 nm thick silicon crystal are also provided. This study opens up the potential for accurate analysis of very thin crystals. Also presented are recent results related to rainbows occurring in proton transmission through carbon nanotubes, and a detailed quantum consideration of the transmission of positrons of an energy of 1 MeV through very short carbon nanotubes. This process is determined by the rainbow effect. The initial positron beam is represented as an ensemble of non-interacting Gaussian wave packets, and the principal and supernumerary primary rainbows appearing in the spatial and angular distributions of transmitted positrons are clearly identified. They are explained by the effects of wrinkling, concentration and coordination of the wave packets.

Silicon technology has developed along virtually one single line: reducing the minimal size of lithographic features. But has this taken us to the point of diminishing returns? Are we now at a turning point in the logical evolution of microelectronics? Some believe that the semiconductor microelectronics industry has matured: the research game is over (comparisons with the steel industry are being made). Others believe that qualitative progress in hardware technology will come roaring back, based on innovative research. This debate, spirited as it is, is reflected in the pages of Future Trends in Microelectronics, where such questions are discussed. What kind of research does the silicon industry need to continue its expansion? What is the technical limit to shrinking Si devices? Is there any economic sense in pursuing this limit? What are the most attractive applications of optoelectronic hybrid systems? Are there any green pastures beyond the traditional semiconductor technologies? Identifying the scenario for the future evolution of microelectronics will present a tremendous opportunity for constructive action today.

In modern electoral processes, Information and Communication Technologies play a crucial role, whether used in voter registration, ballot casting, or processing of results. Securing these systems is a necessary step in ensuring the fairness of the democratic process. Design, Development, and Use of Secure Electronic Voting Systems analyzes current research on the integration of modern technologies with traditional democratic systems, providing a framework for designing and deploying electronic voting systems in any context or society. Stakeholders, researchers, architects, designers, and scholars interested in the use of electronic systems in government processes will use this book to gain a broader understanding of some of the latest advances in this emerging field.

This book describes intuitive analog design approaches using digital inverters, providing filter architectures and circuit techniques enabling high performance analog circuit design. The authors provide process, supply voltage and temperature (PVT) variation-tolerant design techniques for inverter based circuits. They also discuss various analog design techniques for lower technology nodes and lower power supply, which can be used for designing high performance systems-on-chip.

Plasma Processing of Semiconductors contains 28 contributions from 18 experts and covers plasma etching, plasma deposition, plasma-surface interactions, numerical modelling, plasma diagnostics, less conventional processing applications of plasmas, and industrial applications. Audience: Coverage ranges from introductory to state of the art, thus the book is suitable for graduate-level students seeking an introduction to the field as well as established workers wishing to broaden or update their knowledge.

Kalia and Fu's novel monograph covers cryogenic treatment, properties and applications of cryo-treated polymer materials. Written by numerous international experts, the twelve chapters in this book offer the reader a comprehensive picture of the latest findings and developments, as well as an outlook on the field. Cryogenic technology has seen remarkable progress in the past few years and especially cryogenic properties of polymers are attracting attention through new breakthroughs in space, superconducting, magnetic and electronic techniques. This book is a valuable resource for researchers, educators, engineers and graduate students in the field and at technical institutions.

The emergence of highly efficient short-wavelength laser diodes based on the III-V compound semiconductor GaN has not only enabled high-density optical data storage, but is also expected to revolutionize display applications. Moreover, a variety of scientific applications in biophotonics, materials research and quantum optics can benefit from these versatile and cost-efficient laser light sources in the near-UV to green spectral range. This thesis describes the device physics of GaN-based laser diodes, together with recent efforts to achieve longer emission wavelengths and short-pulse emission. Experimental and theoretical approaches are employed to address the individual device properties and optimize the laser diodes toward the requirements of specific applications.

For the past seventy years, ferrites (magnetic ceramics) have been prized for a range of properties that has no equivalent in the existing metal magnetic materials. They have contributed to many important advances in electronics and new high-performance products are appearing all the time. Ferrite technology has produced greater progress in the past 15 years since the first edition was published. Many of the semiconductor and IC technology responsible for the computer and Internet explosion would not have been possible without the magnetic materials technology needed for powering and otherwise exploiting those developments.

Modern Ferrite Technology, 2nd ed, offers the readers an expert overview of the latest ferrite advances as well as their applications in electronic components. This volume develops the interplay among material properties, component specification and device requirements using ferrites. Throughout, emphasis is placed on practical technological concerns as opposed to mathematical and physical aspects of the subject.

The book traces the origin of the magnetic effect in ferrites from the level of the simplest particle and the increases the scope to the larger and larger hierarchies. From the desired magnetic properties the author deduces the physical and chemical material parameters, taking into consideration major chemistry, impurity levels, ceramic microstructures and grain boundary effects. He then discusses the processing conditions and associated conditions required for implementation. In addition to conventional ceramic techniques, he describes non-conventional methods such as coprecipitation, co-spray roasting and single crystal growth.

The secondsection of this book deals with a complete listing of the many important applications in the field including ferrites for permanent magnet, telecommunications, power supplies, memory systems magnetic recording and microwave applications.

The function of ferrites in each of these applications is described. The requirements of the electronic circuit and device are broken down into the individual component specifications with regard to size and configuration. Design criteria for power level, degree of stability and cost are then considered.

Optical Properties of Crystalline and Amorphous Semiconductors: Materials and Fundamental Principles presents an introduction to the fundamental optical properties of semiconductors. This book presents tutorial articles in the categories of materials and fundamental principles (Chapter 1), optical properties in the reststrahlen region (Chapter 2), those in the interband transition region (Chapters 3 and 4) and at or below the fundamental absorption edge (Chapter 5). Optical Properties of Crystalline and Amorphous Semiconductors: Materials and Fundamental Principles is presented in a form which could serve to teach the underlying concepts of semiconductor optical properties and their implementation. This book is an invaluable resource for device engineers, solid-state physicists, material scientists and students specializing in the fields of semiconductor physics and device engineering.

A recent major development in high technology, and one which bears considerable industrial potential, is the advent of low-dimensional semiconductor quantum structures. The research and development activity in this field is moving fast and it is thus important to afford scientists and engineers the opportunity to get updated by the best experts in the field. The present book draws together the latest developments in the fabrication technology of quantum structures, as well as a competent and extensive review of their fundamental properties and some remarkable applications. The book is based on a set of lectures that introduce different aspects of the basic knowledge available, it has a tutorial content and could be used as a textbook. Each aspect is reviewed, from elementary concepts up to the latest developments. Audience: Undergraduates and graduates in electrical engineering and physics schools. Also for active scientists and engineers, updating their knowledge and understanding of the frontiers of the technology.

This reference presents a system analysis of the fibre-optic gyro. Drawing on 15 years of research and developments, it describes the concepts that have emerged as the preferred solutions for obtaining a practical device, and provides access to the information needed to know about optics, single-mode fibre optics and integrated optics to understand the fibre gyro.

"System level testing is becoming increasingly important. It is driven by the incessant march of complexity ... which is forcing us to renew our thinking on the processes and procedures that we apply to test and diagnosis of systems. In fact, the complexity defines the system itself which, for our purposes, is Aany aggregation of related elements that together form an entity of sufficient complexity for which it is impractical to treat all of the elements at the lowest level of detail . System approaches embody the partitioning of problems into smaller inter-related subsystems that will be solved together. Thus, words like hierarchical, dependence, inference, model, and partitioning are frequent throughout this text. Each of the authors deals with the complexity issue in a similar fashion, but the real value in a collected work such as this is in the subtle differences that may lead to synthesized approaches that allow even more progress. The works included in this volume are an outgrowth of the 2nd International Workshop on System Test and Diagnosis held in Alexandria, Virginia in April 1998. The first such workshop was held in Freiburg, Germany, six years earlier. In the current workshop nearly 50 experts from around the world struggled over issues concerning the subject... In this volume, a select group of workshop participants was invited to provide a chapter that expanded their workshop presentations and incorporated their workshop interactions... While we have attempted to present the work as one volume and requested some revision to the work, the content of the individual chapters was not edited significantly. Consequently, you will see different approaches to solving the sameproblems and occasional disagreement between authors as to definitions or the importance of factors. ... The works collected in this volume represent the state-of-the-art in system test and diagnosis, and the authors are at the leading edge of that science...." From the Preface

Reliability of Semiconductor Lasers and Optoelectronic Devices simplifies complex concepts of optoelectronics reliability with approachable introductory chapters and a focus on real-world applications. This book provides a brief look at the fundamentals of laser diodes, introduces reliability qualification, and then presents real-world case studies discussing the principles of reliability and what occurs when these rules are broken. Then this book comprehensively looks at optoelectronics devices and the defects that cause premature failure in them and how to control those defects. Key materials and devices are reviewed including silicon photonics, vertical-cavity surface-emitting lasers (VCSELs), InGaN LEDs and lasers, and AlGaN LEDs, covering the majority of optoelectronic devices that we use in our everyday lives, powering the Internet, telecommunication, solid-state lighting, illuminators, and many other applications. This book features contributions from experts in industry and academia working in these areas and includes numerous practical examples and case studies. This book is suitable for new entrants to the field of optoelectronics working in R&D.

Density functional theory (DFT) has become the standard workhorse for quantum mechanical simulations as it offers a good compromise between accuracy and computational cost.
However, there are many important systems for which DFT performs very poorly, most notably strongly-correlated materials, resulting in a significant recent growth in interest in 'beyond DFT' methods. The widely used DFT+U technique, in particular, involves the addition of explicit Coulomb repulsion terms to reproduce the physics of spatially-localised electronic subspaces.
The magnitude of these corrective terms, measured by the famous Hubbard U parameter, has received much attention but less so for the projections used to delineate these subspaces.
The dependence on the choice of these projections is studied in detail here and a method to overcome this ambiguity in DFT+U, by self-consistently determining the projections, is introduced.
The author shows how nonorthogonal representations for electronic states may be used to construct these projections and, furthermore, how DFT+U may be implemented with a linearly increasing cost with respect to system size.
The use of nonorthogonal functions in the context of electronic structure calculations is extensively discussed and clarified, with new interpretations and results, and, on this topic, this work may serve as a reference for future workers in the field."