Science and Engineering of One- and Zero-Dimensional Semiconductors


Book Description

This volume comprises the proceedings of the NATO Advanced Research Workshop on the Science and Engineering of 1- and O-dimensional semiconductors held at the University of Cadiz from 29th March to 1st April 1989, under the auspices of the NATO International Scientific Exchange Program. There is a wealth of scientific activity on the properties of two-dimensional semiconductors arising largely from the ease with which such structures can now be grown by precision epitaxy techniques or created by inversion at the silicon-silicon dioxide interface. Only recently, however, has there burgeoned an interest in the properties of structures in which carriers are further confined with only one or, in the extreme, zero degrees of freedom. This workshop was one of the first meetings to concentrate almost exclusively on this subject: that the attendance of some forty researchers only represented the community of researchers in the field testifies to its rapid expansion, which has arisen from the increasing availability of technologies for fabricating structures with small enough (sub - O. I/tm) dimensions. Part I of this volume is a short section on important topics in nanofabrication. It should not be assumed from the brevity of this section that there is little new to be said on this issue: rather that to have done justice to it would have diverted attention from the main purpose of the meeting which was to highlight experimental and theoretical research on the structures themselves.




Hot Electrons in Semiconductors


Book Description

Under certain conditions electrons in a semiconductor become much hotter than the surrounding crystal lattice. When this happens, Ohm's Law breaks down: current no longer increases linearly with voltage and may even decrease. Hot electrons have long been a challenging problem in condensed matter physics and remain important in semiconductor research. Recent advances in technology have led to semiconductors with submicron dimensions, where electrons can be confined to two (quantum well), one (quantum wire), or zero (quantum dot) dimensions. In these devices small voltages heat electrons rapidly, inducing complex nonlinear behavior; the study of hot electrons is central to their further development. This book is the only comprehensive and up-to-date coverage of hot electrons. Intended for both established researchers and graduate students, it gives a complete account of the historical development of the subject, together with current research and future trends, and covers the physics of hot electrons in bulk and low-dimensional device technology. The contributions are from leading scientists in the field and are grouped broadly into five categories: introduction and overview; hot electron-phonon interactions and ultra-fast phenomena in bulk and two-dimensional structures; hot electrons in quantum wires and dots; hot electron tunneling and transport in superlattices; and novel devices based on hot electron transport.




Resonant Tunneling in Semiconductors


Book Description

This book contains the proceedings of the NATO Advanced Research Workshop on "Resonant Tunneling in Semiconductors: Physics and Applications", held at Escorial, Spain, on May 14-18, 1990. The tremendous growth in the past two decades in the field of resonant tunneling in semiconductor heterostructures has followed, if not outpaced, the expansion wit nessed in quantum structures in general. Resonant tunneling shares also the multi disciplinary nature of that broad area, with an emphasis on the underlying physics but with a coverage of material systems on the one end and device applications on the other. Indeed, that resonant tunneling provides great flexibility in terms of materials and configurations and that it is inherently a fast process with obvious device impli cations by the presence of a negative differential resistance have contributed to the unrelenting interest in this field. These proceedings consist of 49 refereed articles; they correspond to both invited and contributed talks at the workshop. Because of the intertwinning nature of the subject matter, it has been difficult to subdivide them in well-defined sections. Instead, they are arranged in several broad categories, meant to serve only as guidelines of emphasis on different topics and aspects. The book starts with an introduction to res onant tunneling by providing a perspective of the field in the first article. This is fol lowed by discussions of different material systems with various band-structure effects.




Nanostructured Materials


Book Description

This book discusses the early stages of the development of nanostructures, including synthesis techniques, growth mechanisms, the physics and chemistry of nanostructured materials, various innovative characterization techniques, the need for functionalization and different functionalization methods as well as the various properties of nanostructured materials. It focuses on the applications of nanostructured materials, such as mechanical applications, nanoelectronics and microelectronic devices, nano-optics, nanophotonics and nano-optoelectronics, as well as piezoelectric, agriculture, biomedical and, environmental remediation applications, and anti-microbial and antibacterial properties. Further, it includes a chapter on nanomaterial research developments, highlighting work on the life-cycle analysis of nanostructured materials and toxicity aspects.




Light Scattering in Semiconductor Structures and Superlattices


Book Description

Just over 25 years ago the first laser-excited Raman spectrum of any crystal was obtained. In November 1964, Hobden and Russell reported the Raman spectrum of GaP and later, in June 1965, Russell published the Si spectrum. Then, in July 1965, the forerunner of a series of meetings on light scattering in solids was held in Paris. Laser Raman spectroscopy of semiconductors was at the forefront in new developments at this meeting. Similar meetings were held in 1968 (New York), 1971 (Paris) and 1975 (Campinas). Since then, and apart from the multidisciplinary biennial International Conference on Raman Spectroscopy there has been no special forum for experts in light scattering spectroscopy of semiconductors to meet and discuss latest developments. Meanwhile, technological advances in semiconductor growth have given rise to a veritable renaissance in the field of semiconductor physics. Light scattering spectroscopy has played a crucial role in the advancement of this field, providing valuable information about the electronic, vibrational and structural properties both of the host materials, and of heterogeneous composite structures. On entering a new decade, one in which technological advances in lithography promise to open even broader horirons for semiconductor physics, it seemed to us to be an ideal time to reflect on the achievements of the past decade, to be brought up to date on the current state-of-the-art, and to catch some glimpses of where the field might be headed in the 1990s.




Modern Semiconductor Quantum Physics


Book Description

Modern Semiconductor Quantum Physics has the following constituents: (1) energy band theory: pseudopotential method (empirical and ab initio); density functional theory; quasi-particles; LCAO method; k.p method; spin-orbit splitting; effect mass and Luttinger parameters; strain effects and deformation potentials; temperature effects. (2) Optical properties: absorption and exciton effect; modulation spectroscopy; photo luminescence and photo luminescence excitation; Raman scattering and polaritons; photoionization. (3) Defects and Impurities: effective mass theory and shallow impurity states; deep state cluster method, super cell method, Green's function method; carrier recombination kinetics; trapping transient measurements; electron spin resonance; electron lattice interaction and lattice relaxation effects; multi-phonon nonradiative recombination; negative U center, DX center and EL2 Defects. (4) Semiconductor surfaces: two dimensional periodicity and surface reconstruction; surface electronic states; photo-electron spectroscopy; LEED, STM and other experimental methods. (5) Low-dimensional structures: Heterojunctions, quantum wells; superlattices, quantum-confined Stark effect and Wannier-Stark ladder effects; resonant tunneling, quantum Hall effect, quantum wires and quantum dots.This book can be used as an advanced textbook on semiconductor physics for graduate students in physics and electrical engineering departments. It is also useful as a research reference for solid state scientists and semiconductor device engineers.




Phonons in Semiconductor Nanostructures


Book Description

In the last ten years, the physics and technology of low dimensional structures has experienced a tremendous development. Quantum structures with vertical and lateral confinements are now routinely fabricated with feature sizes below 100 run. While quantization of the electron states in mesoscopic systems has been the subject of intense investigation, the effect of confinement on lattice vibrations and its influence on the electron-phonon interaction and energy dissipation in nanostructures received atten tion only recently. This NATO Advanced Research Workshop on Phonons in Sem iconductor Nanostructures was a forum for discussion on the latest developments in the physics of phonons and their impact on the electronic properties of low-dimensional structures. Our goal was to bring together specialists in lattice dynamics and nanos tructure physics to assess the increasing importance of phonon effects on the physical properties of one-(lD) and zero-dimensional (OD) structures. The Workshop addressed various issues related to phonon physics in III-V, II-VI and IV semiconductor nanostructures. The following topics were successively covered: Models for confined phonons in semiconductor nanostructures, latest experimental observations of confined phonons and electron-phonon interaction in two-dimensional systems, elementary excitations in nanostructures, phonons and optical processes in reduced dimensionality systems, phonon limited transport phenomena, hot electron effects in quasi - ID structures, carrier relaxation and phonon bottleneck in quantum dots.







Hot Carriers in Semiconductors


Book Description

This volume contains invited and contributed papers of the Ninth International Conference on Hot Carriers in Semiconductors (HCIS-9), held July 3 I-August 4, 1995 in Chicago, Illinois. In all, the conference featured 15 invited oral presentations, 60 contributed oral presentations, and 105 poster presentations, and an international contingent of 170 scientists. As in recent conferences, the main themes of the conference were related to nonlinear transport in semiconductor heterojunctions and included Bloch oscillations, laser diode structures, and femtosecond spectroscopy. Interesting questions related to nonlinear transport, size quantization, and intersubband scattering were addressed that are relevant to the new quantum cascade laser. Many lectures were geared toward quantum wires and dots and toward nanostructures and mesoscopic systems in general. It is expected that such research will open new horizons to nonlinear transport studies. An attempt was made by the program committee to increase the number of presen tations related directly to devices. The richness of nonlocal hot electron effects that were discussed as a result, in our opinion, suggests that future conferences should further encourage reports on such device research. On behalf of the Program and International Advisory Committees, we thank the participants, who made the conference a successful and pleasant experience, and the support of the Army Research Office, the Office of Naval Research, and the Beckman Institute of the University of Illinois at Urbana-Champaign. We are also indebted to Mrs. Sara Starkey and Mrs.




Delta-doping of Semiconductors


Book Description

This book is the first to give a comprehensive review of the theory, fabrication, characterisation, and device applications of abrupt, shallow, and narrow doping profiles in semiconductors. Such doping profiles are a key element in the development of modern semiconductor technology. After an introductory chapter setting out the basic theoretical and experimental concepts involved, the fabrication of abrupt and narrow doping profiles by several different techniques, including epitaxial growth, is discussed. The techniques for characterising doping distributions are then presented, followed by several chapters devoted to the inherent physical properties of narrow doping profiles. The latter part of the book deals with specific devices. The book will be of great interest to graduate students, researchers and engineers in the fields of semiconductor physics and microelectronic engineering.