Download or read book Coherent Strain Changes in Si Ge Alloys Grown by Ion Assisted Molecular Beam Epitaxy written by H. A. Atwater and published by . This book was released on 1992 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although low energy ion bombardment has been employed in various contexts epitaxial growth, such as enhanced dopant incorporation, surface cleaning during plasma enhanced chemical vapor deposition, and direct low energy ion beam deposition, key questions about the interaction of low energy ions with growing surfaces remain unanswered. Improved understanding of ion-surface interactions during growth may yield additional elements of control over epitaxial film structure, strain state, and composition. Of particular interest for high quality epitaxial films is the identification of the regime in which surface and near-surface processes, such as surface diffusion and incorporation at growth sites, can be enhanced at low temperatures while avoiding or controlling damage in the deposited films.

Download or read book Diffusion and Defect Data written by and published by . This book was released on 1992 with total page 1120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interface Dynamics and Growth Volume 237 written by Keng S. Liang and published by . This book was released on 1992-05-29 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.

Download or read book Strained Ge and GeSn Band Engineering for Si Photonic Integrated Circuits written by Yijie Huo and published by Stanford University. This book was released on 2010 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: The on-chip interconnect bandwidth limitation is becoming an increasingly critical challenge for integrated circuits (ICs) as device scaling continues to push the speed and density of ICs. Silicon photonics has the ability to solve this emerging problem due to its high speed, high bandwidth, low power consumption, and ability to be monolithically integrated on silicon. Most of the key devices for Si photonic ICs have already been demonstrated. However, a practical CMOS compatible coherent light source is still a major challenge. Germanium (Ge) has already been demonstrated to be a promising material for optoelectronic devices, such as photo-detectors and modulators. However, Ge is an indirect band gap semiconductor, which makes Ge-based light sources very inefficient and limits their practical use. Fortunately, the direct [uppercase Gamma] valley of the Ge conduction band is only 0.14 eV higher than the indirect L valley, suggesting that with band-structure engineering, Ge has the potential to become a direct band gap material and an efficient light emitter. In this dissertation, we first discuss our work on highly biaxial tensile strained Ge grown by molecular beam epitaxy (MBE). Relaxed step-graded InGaAs buffer layers, which are prepared with low temperature growth and high temperature annealing, are used to provide a larger lattice constant substrate to produce tensile strain in Ge epitaxial layers. Up to 2.3% in-plane biaxial tensile strained thin Ge epitaxial layers were achieved with smooth surfaces and low threading dislocation density. A strong increase of photoluminescence with highly tensile strained Ge layers at low temperature suggests that a direct band gap semiconductor has been achieved. This dissertation also presents our work on more than 9% Sn incorporation in epitaxial GeSn alloys using a low temperature MBE growth method. This amount of Sn is 10 times greater than the solid-solubility of Sn in crystalline Ge. Material characterization shows good crystalline quality without Sn precipitation or phase segregation. With increasing Sn percentage, direct band gap narrowing is observed by optical transmission measurements. The studies described in this dissertation will help enable efficient germanium based CMOS compatible coherent light sources. Other possible applications of this work are also discussed in the concluding chapter.

Download or read book Evolution of Thin Film and Surface Microstructure Volume 202 written by C. V. Thompson and published by . This book was released on 1991-05-31 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.

Download or read book Growth and Characterization of Si Ge Structures Grown by Molecular Beam Epitaxy written by Robert Michael Ostrom and published by . This book was released on 1989 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growth and Characterization of Strain engineered Si SiGe Heterostructures Prepared by Molecular Beam Epitaxy written by and published by . This book was released on 2008 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Megaelectron Volt Ion Beam Induced Epitaxy of Deposited Silicon and Germanium silicon Alloys on 100 Silicon Substrates written by Anthony J. Yu and published by . This book was released on 1989 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book SiGe and Si Strained Layer Epitaxy for Silicon Heterostructure Devices written by John D. Cressler and published by CRC Press. This book was released on 2017-12-19 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: What seems routine today was not always so. The field of Si-based heterostructures rests solidly on the shoulders of materials scientists and crystal growers, those purveyors of the semiconductor “black arts” associated with the deposition of pristine films of nanoscale dimensionality onto enormous Si wafers with near infinite precision. We can now grow near-defect free, nanoscale films of Si and SiGe strained-layer epitaxy compatible with conventional high-volume silicon integrated circuit manufacturing. SiGe and Si Strained-Layer Epitaxy for Silicon Heterostructure Devices tells the materials side of the story and details the many advances in the Si-SiGe strained-layer epitaxy for device applications. Drawn from the comprehensive and well-reviewed Silicon Heterostructure Handbook, this volume defines and details the many advances in the Si/SiGe strained-layer epitaxy for device applications. Mining the talents of an international panel of experts, the book covers modern SiGe epitaxial growth techniques, epi defects and dopant diffusion in thin films, stability constraints, and electronic properties of SiGe, strained Si, and Si-C alloys. It includes appendices on topics such as the properties of Si and Ge, the generalized Moll-Ross relations, integral charge-control relations, and sample SiGe HBT compact model parameters.

Download or read book Growth and Characterization of GeSn and SiGeSn Alloys for Optical Interconnects written by Hai Lin and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few decades, the microelectronics industry has achieved previously unimagined success. Following Moore's law, the number of transistors in a chip has approximately doubled every 18 months and the size of a transistor has reduced down to 32nm. However, as the device size scales down, one of the major limitations in today's silicon integrated circuits comes from the electrical interconnects. In order to increase the interconnect density and decrease the interconnect energy, optical interconnects between chips or even on-chip have been proposed and widely investigated. The big challenge of integrating optics onto a Si chip is the compatibility, so group IV materials are considered. Optoelectronic devices for optical interconnects, such as modulators and detectors, have been demonstrated using both Si and Ge. A major issue now is the lack of a Si compatible light source. Because Si itself has very poor light emitting efficiency, current research focuses on Ge based semiconductors. There are two promising approaches to modify the band structure of Ge and make it a direct band gap material. This dissertation focuses on both of these approaches: applying biaxial tensile strain and alloying with Tin (Sn). In addition, combining these two methods is expected to achieve the goal with a more stable materials system. Therefore the ability to decouple these two effects and investigate the material properties independently is critical in our research. Ge1-xSnx alloys were grown by molecular beam epitaxy (MBE) machines at low growth temperatures (150-200°C) on InGaAs buffer layers on GaAs substrates. Ge1-xSnx alloys with up to 10.5% Sn have been demonstrated with high crystal quality in this dissertation. Crystal quality of Ge1-xSnx layers was characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM). Composition and strain were studied by X-ray diffraction (XRD), secondary ion mass spectroscopy (SIMS) and X-ray photoelectron spectroscopy (XPS). The optical properties of Ge1-xSnx alloys were determined by photoreflectance (PR) and photoluminescence (PL). The advantage of using InGaAs buffer layers is the separate control of the strain and composition effects on the material properties of Ge1-xSnx alloys. In this dissertation, Ge1-xSnx alloys with different Sn compositions and various levels of strain were grown. Room temperature PR measurements were used in this work to determine the direct bandgap from the maxima of the light- and heavy-hole bands to the bottom of [upper case Gamma] valley. The energy bowing parameter (bGeSn) was calculated from the bandgap of unstrained Ge1-xSnx alloys to describe the composition effect. The indirect to direct band gap transition for unstrained Ge1-xSnx alloys was estimated to be around 6~7% Sn composition from low-temperature PL studies. The effect of biaxial strain on the direct band gap, described by two deformation potentials (a and b), was investigated for the first time as well. These basic parameters are very useful for the design of optoelectronic devices based on strained Ge1-xSnx alloys. Additionally, the strain and composition contributions to Raman shift of Ge-Ge LO peak in Ge1-xSnx alloys were quantified separately as well. Moreover, Ge1-xSnx/ SixGe1-x-ySny quantum well (QW) structures are of great interest for photonic devices. Due to the large direct band gap of Si, SixGe1-x-ySny alloys have larger bandgap energies than Ge1-xSnx alloys by design, so as barrier layers they can confine injected carriers inside the active Ge1-xSnx well. Good crystal quality of SixGe1-x-ySny alloys were grown by MBE at low temperatures and annealed by RTA at 500°C in a forming gas ambient. The decoupling of the direct band gap and lattice constant of SixGe1-x-ySny alloys were demonstrated. This feature simplifies the strain engineering in QW designs. Finally, PL from SixGe1-x-ySny/Ge1-xSnx/ SixGe1-x-ySny double heterostructure was demonstrated experimentally for the first time. The measured PL peak energy matches the calculated value at room temperature, indicating that the basic materials properties determined in this dissertation are accurate. The observation of PL proves that these group IV alloys are promising candidates to make a Si-compatible laser for on chip optical interconnects.

Download or read book Epitaxy and Applications of Si Based Heterostructures Volume 533 written by Eugene A. Fitzgerald and published by . This book was released on 1998 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The April 13-17, 1998 symposium held in San Francisco offered an intriguing mix of SiGe device and circuit technology, and the latest developments in SiGE materials and SiGeC alloys. The 53 papers pivot around the themes of: technologies and devices; devices, processing, and characterization; photonics and optoelectronics; epitaxy of quantum structures; SiGeC alloys; and epitaxy of SiGe/ related materials. A sample title from each of the six parts includes: carrier transport and velocity overshoot in strained Si on SiGe heterostructures, device and fabrication issues of high-performance Si/SiGe FETS, photonic crystals based on macroporous silicon, stacked layers of self-assembled Ge islands, photoluminescence in strain compensated Si/SiGeC multiple quantum wells, and a novel layer-by-layer heteroepitaxy of germanium on silicon (100) surface. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book Carbon Incorporation Pathways and Lattice Site Distribution in Si1 yCy Si 001 and Ge1 yCy Ge 001 Alloys Grown by Molecular Beam Epitaxy written by Se-Yang Park and published by . This book was released on 2001 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Substrate Engineering and Strain Effects on the Growth of Ge on Si written by Paul Rugheimer and published by . This book was released on 2004 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book GeSi Strained Layers and Their Applications A Reprint Volume written by A. M. Stoneham and published by CRC Press. This book was released on 1995 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents key papers published in recent years dealing with silicon-germanium strained layers and their applications.Papers are presented in three groups, dealing with growth and mechanical properties of strained layers, electronic and optical properties, and applications, notably in novel diode and transistor designs and high performance optical detectors. The collected papers will be an ideal source for new researchers who need quick and easy access to an authoritative selection of high quality papers. An important aspect of the selection is the cross-disciplinary nature of the papers, presenting material from electronic engineers as well as from physicists and materials scientists. An extensive bibliography gives details of a further 250 papers on the subject.

Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1074 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1992-12 with total page 2022 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2668 pages. Available in PDF, EPUB and Kindle. Book excerpt: