Download or read book High Speed Germanium Silicon Modulators For Optical Interconnect written by Yiwen Rong and published by LAP Lambert Academic Publishing. This book was released on 2014-11-28 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information processing requires interconnects to carry information from one place to another. Optical interconnects between electronics systems have attracted significant attention and development for a number of years because optical links have demonstrated potential advantages for high-speed, low-power, and interference immunity. With increasing system speed and greater bandwidth requirements, the distance over which optical communication is useful has continually decreased to chip-to-chip and on-chip levels. Monolithic integration of photonics and electronics will significantly reduce the cost of optical components and further combine the functionalities of chips on the same or different boards or systems. Modulators are one of the fundamental building blocks for optical interconnects.

Download or read book High Speed Low Driving Voltage Vertical Cavity Germanium silicon Modulators for Optical Interconnect written by Yiwen Rong and published by Stanford University. This book was released on 2010 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information processing requires interconnects to carry information from one place to another. Optical interconnects between electronics systems have attracted significant attention and development for a number of years because optical links have demonstrated potential advantages for high-speed, low-power, and interference immunity. With increasing system speed and greater bandwidth requirements, the distance over which optical communication is useful has continually decreased to chip-to-chip and on-chip levels. Monolithic integration of photonics and electronics will significantly reduce the cost of optical components and further combine the functionalities of chips on the same or different boards or systems. Modulators are one of the fundamental building blocks for optical interconnects. Previous work demonstrated modulators based upon the quantum confined Stark effect (QCSE) in SiGe p-i-n devices with strained Ge/SiGe multi-quantum-well (MQW) structures in the i region. While the previous work demonstrated the effect, it did not examine the high-speed aspects of the device, which is the focus of this dissertation. High-speed modulation and low driving voltage are the keys for the device's practical use. At lower optical intensity operation, the ultimate limitation in speed will be the RC time constant of the device itself. At high optical intensity, the large number of photo generated carriers in the MQW region will limit the performance of the device through photo carrier related voltage drop and exciton saturation. In previous work, the devices consist of MQWs configured as p-i-n diodes. The electric field induced absorption change by QCSE modulates the optical transmission of the device. The focus of this thesis is the optimization of MQW material deposition, minimization of the parasitic capacitance of the probe pads for high speed, low voltage and high contrast ratio operation. The design, fabrication and high-speed characterization of devices of different sizes, with different bias voltages are presented. The device fabrication is based on processes for standard silicon electronics and is suitable for mass-production. This research will enable efficient transceivers to be monolithically integrated with silicon chips for high-speed optical interconnects. We demonstrated a modulator, with an eye diagram of 3.125GHz, a small driving voltage of 2.5V and an f3dB bandwidth greater than 30GHz. Carrier dynamics under ultra-fast laser excitation and high-speed photocurrent response are also investigated.

Download or read book High Speed Low Driving Voltage Vertical Cavity Germanium silicon Modulators for Optical Interconnect written by Yiwen Rong and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Information processing requires interconnects to carry information from one place to another. Optical interconnects between electronics systems have attracted significant attention and development for a number of years because optical links have demonstrated potential advantages for high-speed, low-power, and interference immunity. With increasing system speed and greater bandwidth requirements, the distance over which optical communication is useful has continually decreased to chip-to-chip and on-chip levels. Monolithic integration of photonics and electronics will significantly reduce the cost of optical components and further combine the functionalities of chips on the same or different boards or systems. Modulators are one of the fundamental building blocks for optical interconnects. Previous work demonstrated modulators based upon the quantum confined Stark effect (QCSE) in SiGe p-i-n devices with strained Ge/SiGe multi-quantum-well (MQW) structures in the i region. While the previous work demonstrated the effect, it did not examine the high-speed aspects of the device, which is the focus of this dissertation. High-speed modulation and low driving voltage are the keys for the device's practical use. At lower optical intensity operation, the ultimate limitation in speed will be the RC time constant of the device itself. At high optical intensity, the large number of photo generated carriers in the MQW region will limit the performance of the device through photo carrier related voltage drop and exciton saturation. In previous work, the devices consist of MQWs configured as p-i-n diodes. The electric field induced absorption change by QCSE modulates the optical transmission of the device. The focus of this thesis is the optimization of MQW material deposition, minimization of the parasitic capacitance of the probe pads for high speed, low voltage and high contrast ratio operation. The design, fabrication and high-speed characterization of devices of different sizes, with different bias voltages are presented. The device fabrication is based on processes for standard silicon electronics and is suitable for mass-production. This research will enable efficient transceivers to be monolithically integrated with silicon chips for high-speed optical interconnects. We demonstrated a modulator, with an eye diagram of 3.125GHz, a small driving voltage of 2.5V and an f3dB bandwidth greater than 30GHz. Carrier dynamics under ultra-fast laser excitation and high-speed photocurrent response are also investigated.

Download or read book High performance Ge SiGe Quantum Well Waveguide Modulators for Optical Interconnect Systems written by Stephanie Ann Claussen and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical interconnects have the potential to help create faster, more powerful computers that use far less energy than they currently do. However, to accomplish this goal, key material and device design breakthroughs must first occur. This Ph. D. dissertation focuses on developing the technology for one component of future optical interconnects, the optical modulator. Ge/SiGe quantum wells exhibit the quantum-confined Stark effect, the strongest high-speed electroabsorption modulation mechanism available in a CMOS-compatible material. We begin by examining the ultrafast carrier dynamics of these quantum wells as a way to understand the fundamental limitations to optical modulators which rely on this material. Using a pump-probe experimental setup, we measured the intervalley scattering time of electrons from the direct valley to the indirect L valley in the conduction band of the germanium wells to be ~185 fs. We also measured field screening in these quantum wells and modeled its recovery through diffusive conduction within 120 ps. This improved understanding of Ge/SiGe quantum wells allowed us to design a waveguide-integrated modulator that relies on selective area growth of this material in thick silicon-on-insulator waveguides. Selective area quantum well waveguide modulators offer the potential of high contrast ratios, low operating energies, and low loss. We developed a novel growth substrate fabrication process to enable high quality selective area growth of Ge/SiGe quantum wells with minimal sidewall growth. We then fabricated selective area modulators integrated with SOI waveguides, and present here preliminary results from these devices.

Download or read book Ge SiGe Quantum Well Waveguide Modulator for Optical Interconnect Systems written by Ren Shen and published by Stanford University. This book was released on 2011 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thanks to the development of silicon VLSI technology over the past several decades, we can now integrate far more transistors onto a single chip than ever before. However, this also imposes more stringent requirements, in terms of bandwidth, density, and power consumption, on the interconnect systems that link transistors. The interconnect system is currently one of the major hurdles for the further advancement of the electronic technology. Optical interconnect is considered a promising solution to overcome the interconnect bottleneck. The quantum-confined Stark effect in Ge/SiGe quantum well system paves the way to realize efficient optical modulation on Si in a fully CMOS compatible fashion. In this dissertation, we investigate the integration of Ge/SiGe quantum well waveguide modulators with silicon-on-insulator waveguides. For the first time, we demonstrate the selective epitaxial growth of Ge/SiGe quantum well structures on patterned Si substrates. The selective epitaxy exhibits perfect selectivity and minimal pattern sensitivity. Compared to their counterparts made using bulk epitaxy, the p-i-n diodes from selective epitaxy demonstrate very low reverse leakage current and high reverse breakdown voltage. Strong quantum-confined Stark effect (QCSE) is, for the first time, demonstrated in this material system in the telecommunication C-band at room temperature. A 3 dB optical modulation bandwidth of 2.8 THz is measured, covering more than half of the C-band. We propose, analyze, and experimentally demonstrate a novel approach to realize butt coupling between a SOI waveguide and a selectively grown Ge/SiGe quantum well waveguide modulator using a thin dielectric spacer. Through numerical simulation, we show that the insertion loss penalty for a thin 20 nm thick spacer can be as low as 0.13 dB. Such a quantum well waveguide modulator with a footprint of 8 [Mu]m2 has also been fabricated, demonstrating 3.2 dB modulation contrast with merely 1V swing at a speed of 16 Gpbs.

Download or read book Surface normal Germanium Quantum Well Modulators for Free space Optical Interconnects to Silicon written by Ross Michael Audet and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Today's computer systems are constrained by the high power consumption and limited bandwidth of inter- and intra-chip electrical interconnections. Optical links could alleviate these problems, provided that the optical and electronic elements are tightly integrated. Most present optical modulators use materials systems that are incompatible with CMOS device fabrication, or rely on weak electrooptic effects that are difficult to utilize for vertical incidence devices. The extremely high communications bandwidth demands of future silicon chips may ultimately require massively parallel free-space optical links based on array integration of such vertical incidence modulators. We have investigated the suitability of surface-normal asymmetric Fabry-Perot electroabsorption modulators for short-distance optical interconnections between silicon chips. These modulators should be made as small as possible to minimize device capacitance; however, size-dependent optical properties impose constraints on the dimensions. We have thus performed simulations that demonstrate how the optical performance of the modulators depends on both the spot size of the incident beam and the dimensions of the device. We also discuss the tolerance to nonidealities such as surface roughness and beam misalignment. The particular modulators considered here are structures based upon the quantum-confined Stark effect in Ge/SiGe quantum wells. We present device designs that have predicted extinction ratios greater than 7 dB and switching energies as low as 10 fF/bit, which suggests that these CMOS-compatible devices can enable high interconnect bandwidths without the need for wavelength division multiplexing. Next, we present experimental results from these Ge/SiGe asymmetric Fabry-Perot modulators. Several approaches were investigated for forming resonant cavities using high-index-contrast Bragg mirrors around the Ge/SiGe quantum well active regions. These include fabrication on double-silicon-on-insulator reflecting substrates, a layer transfer and etch-back process using anodic bonding, and alkaline etching the backside of the Si substrate to leave suspended SiGe membranes. We present results from each of these modulator structures. The best performance is achieved from the SiGe membrane modulators, which are the first surface-normal resonant-cavity reflection modulators fabricated entirely on standard silicon substrates. Electroabsorption and electrorefraction both contribute to the reflectance modulation. The devices exhibit greater than 10 dB extinction ratio with low insertion loss of 1.3 dB. High-speed modulation with a 3 dB bandwidth of 4 GHz is demonstrated. The moderate-Q cavity (Q~600) yields an operating bandwidth of more than 1 nm and permits operation without active thermal stabilization.

Download or read book Silicon Photonics III written by Lorenzo Pavesi and published by Springer Science & Business Media. This book was released on 2016-01-08 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is volume III of a series of books on silicon photonics. It reports on the development of fully integrated systems where many different photonics component are integrated together to build complex circuits. This is the demonstration of the fully potentiality of silicon photonics. It contains a number of chapters written by engineers and scientists of the main companies, research centers and universities active in the field. It can be of use for all those persons interested to know the potentialities and the recent applications of silicon photonics both in microelectronics, telecommunication and consumer electronics market.

Download or read book High Efficiency Silicon Photonic Interconnects written by Liang Cao and published by . This book was released on 2014 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Silicon photonic has provided an opportunity to enhance future processor speed by replacing copper interconnects with an on chip optical network. Although photonics are supposed to be efficient in terms of power consumption, speed, and bandwidth, the existing silicon photonic technologies involve problems limiting their efficiency. Examples of limitations to efficiency are transmission loss, coupling loss, modulation speed limited by electro-optical effect, large amount of energy required for thermal control of devices, and the bandwidth limit of existing optical routers. The objective of this dissertation is to investigate novel materials and methods to enhance the efficiency of silicon photonic devices. The first part of this dissertation covers the background, theory and design of on chip optical interconnects, specifically silicon photonic interconnects. The second part describes the work done to build a 300mm silicon photonic library, including its process flow, comprised of basic elements like electro-optical modulators, germanium detectors, Wavelength Division Multiplexing (WDM) interconnects, and a high efficiency grating coupler. The third part shows the works done to increase the efficiency of silicon photonic modulators, unitizing the X(3) nonlinear effect of silicon nanocrystals to make X(2) electro-optical modulators on silicon, and increasing the efficiency of thermal control by incorporating micro-oven structures in electro-optical modulators. The fourth part introduces work done on dynamic optical interconnects including a broadband optical router, single photon level adiabatic wavelength conversion, and optical signal delay. The final part summarizes the work and talks about future development."--Abstract.

Download or read book Strained Germanium Technology for On chip Optical Interconnects written by Donguk Nam and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the invention of the first transistor over half a century ago, transistor scaling has led the semiconductor industry to blossom. Despite the improved performance of scaled transistors, however, the computational speed of integrated circuits (IC) has now become limited by their electrical interconnects. To alleviate this performance bottleneck in ICs, optical interconnects, which have already revolutionized long-haul communications, have recently gained much attention for on-chip applications. Over the past decade many of the key constituents of an on-chip optical interconnect system, such as high-performance photodetectors and modulators, have been demonstrated on a silicon-compatible platform. However, an efficient light source remains particularly challenging: silicon and silicon-compatible materials such as germanium (Ge) are not readily suitable for light emission because their band gaps are indirect. It has been proposed to use tensile strain to make Ge's band gap direct and therefore suitable for light emission, however experimental realization has thus far been lacking. In this dissertation, we focus on developing an efficient silicon-compatible light emitter based on strained Ge technology. Starting from theoretical calculations showing how tensile strain can improve the light emission efficiency of Ge, we present several approaches for enhancing light emission from highly strained Ge on a CMOS-compatible platform. In the first part, we describe a thin film membrane technique in which a large residual stress in a tungsten layer is used as a stressor to induce a biaxial strain in a Ge membrane, upon which we have fabricated optoelectronic devices. In the second part, we introduce an approach to induce uniaxial strain that can potentially create a direct band gap in Ge wire using geometrical amplification of a small pre-existing strain. Lastly, we present a novel way to mimic double-heterostructure behavior within a single material, further enhancing light emission from Ge by capturing photo-generated carriers within a strain-induced potential well. Throughout this dissertation, we discuss the implications of these experimental achievements towards creating an efficient Ge laser for use in silicon-compatible optical interconnects.

Download or read book Optical Fiber Telecommunications VA written by Tingye Li and published by Elsevier. This book was released on 2010-07-28 with total page 945 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Fiber Telecommunications V (A&B) is the fifth in a series that has chronicled the progress in the research and development of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition not only brings a fresh look to many essential topics but also focuses on network management and services. Using high bandwidth in a cost-effective manner for the development of customer applications is a central theme. This book is ideal for R&D engineers and managers, optical systems implementers, university researchers and students, network operators, and the investment community. Volume (A) is devoted to components and subsystems, including: semiconductor lasers, modulators, photodetectors, integrated photonic circuits, photonic crystals, specialty fibers, polarization-mode dispersion, electronic signal processing, MEMS, nonlinear optical signal processing, and quantum information technologies. Volume (B) is devoted to systems and networks, including: advanced modulation formats, coherent systems, time-multiplexed systems, performance monitoring, reconfigurable add-drop multiplexers, Ethernet technologies, broadband access and services, metro networks, long-haul transmission, optical switching, microwave photonics, computer interconnections, and simulation tools. Biographical Sketches Ivan Kaminow retired from Bell Labs in 1996 after a 42-year career. He conducted seminal studies on electrooptic modulators and materials, Raman scattering in ferroelectrics, integrated optics, semiconductor lasers (DBR , ridge-waveguide InGaAsP and multi-frequency), birefringent optical fibers, and WDM networks. Later, he led research on WDM components (EDFAs, AWGs and fiber Fabry-Perot Filters), and on WDM local and wide area networks. He is a member of the National Academy of Engineering and a recipient of the IEEE/OSA John Tyndall, OSA Charles Townes and IEEE/LEOS Quantum Electronics Awards. Since 2004, he has been Adjunct Professor of Electrical Engineering at the University of California, Berkeley. Tingye Li retired from AT&T in 1998 after a 41-year career at Bell Labs and AT&T Labs. His seminal work on laser resonator modes is considered a classic. Since the late 1960s, He and his groups have conducted pioneering studies on lightwave technologies and systems. He led the work on amplified WDM transmission systems and championed their deployment for upgrading network capacity. He is a member of the National Academy of Engineering and a foreign member of the Chinese Academy of Engineering. He is a recipient of the IEEE David Sarnoff Award, IEEE/OSA John Tyndall Award, OSA Ives Medal/Quinn Endowment, AT&T Science and Technology Medal, and IEEE Photonics Award. Alan Willner has worked at AT&T Bell Labs and Bellcore, and he is Professor of Electrical Engineering at the University of Southern California. He received the NSF Presidential Faculty Fellows Award from the White House, Packard Foundation Fellowship, NSF National Young Investigator Award, Fulbright Foundation Senior Scholar, IEEE LEOS Distinguished Lecturer, and USC University-Wide Award for Excellence in Teaching. He is a Fellow of IEEE and OSA, and he has been President of the IEEE LEOS, Editor-in-Chief of the IEEE/OSA J. of Lightwave Technology, Editor-in-Chief of Optics Letters, Co-Chair of the OSA Science & Engineering Council, and General Co-Chair of the Conference on Lasers and Electro-Optics.

Download or read book CMOS Compatible Key Engineering Devices for High Speed Silicon Based Optical Interconnections written by Jing Wang and published by Springer. This book was released on 2018-11-23 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses some research results for CMOS-compatible silicon-based optical devices and interconnections. With accurate simulation and experimental demonstration, it provides insights on silicon-based modulation, advanced multiplexing, polarization and efficient coupling controlling technologies, which are widely used in silicon photonics. Researchers, scientists, engineers and especially students in the field of silicon photonics can benefit from the book. This book provides valuable knowledge, useful methods and practical design that can be considered in emerging silicon-based optical interconnections and communications. And it also give some guidance to student how to organize and complete an good dissertation.

Download or read book Optical Interconnects for Future Data Center Networks written by Christoforos Kachris and published by Springer Science & Business Media. This book was released on 2012-11-07 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Interconnects in Future Data Center Networks covers optical networks and how they can be used to provide high bandwidth, energy efficient interconnects for future data centers with increased communication bandwidth requirements. This contributed volume presents an integrated view of the future requirements of the data centers and serves as a reference work for some of the most advanced solutions that have been proposed by major universities and companies. Collecting the most recent and innovative optical interconnects for data center networks that have been presented in the research community by universities and industries, this book is a valuable reference to researchers, students, professors and engineers interested in the domain of high performance interconnects and data center networks. Additionally, Optical Interconnects in Future Data Center Networks provides invaluable insights into the benefits and advantages of optical interconnects and how they can be a promising alternative for future data center networks.

Download or read book Integrated Optical Interconnect Architectures for Embedded Systems written by Ian O'Connor and published by Springer Science & Business Media. This book was released on 2012-11-07 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a broad overview of current research in optical interconnect technologies and architectures. Introductory chapters on high-performance computing and the associated issues in conventional interconnect architectures, and on the fundamental building blocks for integrated optical interconnect, provide the foundations for the bulk of the book which brings together leading experts in the field of optical interconnect architectures for data communication. Particular emphasis is given to the ways in which the photonic components are assembled into architectures to address the needs of data-intensive on-chip communication, and to the performance evaluation of such architectures for specific applications.

Download or read book Optical Interconnects for Data Centers written by Tolga Tekin and published by Woodhead Publishing. This book was released on 2016-11-01 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current data centre networks, based on electronic packet switches, are experiencing an exponential increase in network traffic due to developments such as cloud computing. Optical interconnects have emerged as a promising alternative offering high throughput and reduced power consumption. Optical Interconnects for Data Centers reviews key developments in the use of optical interconnects in data centres and the current state of the art in transforming this technology into a reality. The book discusses developments in optical materials and components (such as single and multi-mode waveguides), circuit boards and ways the technology can be deployed in data centres. Optical Interconnects for Data Centers is a key reference text for electronics designers, optical engineers, communications engineers and R&D managers working in the communications and electronics industries as well as postgraduate researchers. Summarizes the state-of-the-art in this emerging field Presents a comprehensive review of all the key aspects of deploying optical interconnects in data centers, from materials and components, to circuit boards and methods for integration Contains contributions that are drawn from leading international experts on the topic

Download or read book SiGe Ge and Related Compounds Materials Processing and Devices 8 written by Q. Liu and published by The Electrochemical Society. This book was released on 2018-09-21 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Interconnects written by Lorenzo Pavesi and published by Springer. This book was released on 2007-05-17 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Interconnects provides a fascinating picture of the state of the art in optical interconnects and a perspective on what can be expected in the near future. It is composed of selected reviews authored by world leaders in the field, and these reviews are written from either an academic or industrial viewpoint. An in-depth discussion of the path towards fully-integrated optical interconnects in microelectronics is presented. This book will be useful not only to physicists, chemists, materials scientists, and engineers but also to graduate students who are interested in the fields of microelectronics and optoelectronics.

Download or read book Advanced Interconnects for ULSI Technology written by Mikhail Baklanov and published by John Wiley & Sons. This book was released on 2012-02-17 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finding new materials for copper/low-k interconnects is critical to the continuing development of computer chips. While copper/low-k interconnects have served well, allowing for the creation of Ultra Large Scale Integration (ULSI) devices which combine over a billion transistors onto a single chip, the increased resistance and RC-delay at the smaller scale has become a significant factor affecting chip performance. Advanced Interconnects for ULSI Technology is dedicated to the materials and methods which might be suitable replacements. It covers a broad range of topics, from physical principles to design, fabrication, characterization, and application of new materials for nano-interconnects, and discusses: Interconnect functions, characterisations, electrical properties and wiring requirements Low-k materials: fundamentals, advances and mechanical properties Conductive layers and barriers Integration and reliability including mechanical reliability, electromigration and electrical breakdown New approaches including 3D, optical, wireless interchip, and carbon-based interconnects Intended for postgraduate students and researchers, in academia and industry, this book provides a critical overview of the enabling technology at the heart of the future development of computer chips.