Integrated optoelectronic materials and circuits for optical interconnects

Conventional interconnect and switching technology is rapidly becoming a critical issue in the realization of systems using high speed silicon and GaAs based technologies. In recent years clock speeds and on-chip density for VLSI/VHSIC technology has made packaging these high speed chips extremely difficult. A strong case can be made for using optical interconnects for on-chip/on-wafer, chip-to-chip and board-to-board high speed communications. GaAs Integrated Optoelectronic Circuits (IOC's) are being developed in a number of laboratories for performing Input/Output functions at all levels. In this paper integrated optoelectronic materials, electronics and optoelectronic devices are presented. IOC’s are examined from the standpoint of what it takes to fabricate the devices and what performance can be expected.     

Optical and optoelectronic devices for optical fiber transmissionsystems

The present status and research trends in light sources, detectors, and various optical components are described, focusing mainly on those for single-mode fiber systems. Laser-diode and light-emitting-diode sources are described, and their problems and advantages are examined. The features of optical detectors, namely, avalanche and p-i-n photodiodes are discussed. A method of comparing the performance of optical receivers with different detectors, by examining the minimum detectable power at a specified error probability for the received pulses, is presented. Optical components such as optical filters, couplers, dividers, isolators, connectors, and switches are considered briefly. The potential of optoelectronic integrated circuits is discussed     

Semiconductor optoelectronic devices for free-space optical communications

LIGHT emitting devices based AlGaAs lasers are very useful radiation sources in free-space opticalcommunications systems. Following a brief review of the properties of individual injection lasers, more complex devices are described. These include (or are relevant to) monolithic integration configurations of the lasers with their electronic driving circuitry, power combining methods of semiconductor lasers, and electronic methods of steering the radiation patterns of semiconductor lasers and laser arrays. Fabrication of such devices is one of the major prerequisites for realizing fully the potential advantages of free-space optical communications.     

A BJT translinear loop based optoelectronic integrated circuit with variable transimpedance for optical storage systems

A 0.35 μm SiGe BiCMOS optical receiver with voltage-controlled transimpedance is presented. A variable-gain current amplifier using a BJT translinear loop is applied. A transimpedance dynamic range of 1554 (63.8 dB) with the largest transimpedance of 2.84 MΩ, a bandwidth up to 379 MHz, and a transimpedance bandwidth product up to 168 TΩHz are achieved.     

Integrated optical/optoelectronic switch for parallel opticalinterconnects

A monolithic optical/optoelectronic switch for a reconfigurable, parallel optical interconnect is described. By integrating a vertical-cavity surface-emitting laser with a three-terminal GaAs-AlGaAs heterojunction phototransistor, the functions of an optical transceiver and an optical space switch are combined. Switching experiments demonstrate optical/optoelectronic switching and data conversion at 200 Mbit/s     

InGaAsP/InP long wavelength optoelectronic integrated circuits (OEIC's) for high-speed optical fiber communication systems

This paper describes long wavelength InP-based OEIC's, in which optical components and electrical components are monolithically integrated on a single chip. Recent progress in the InP-based OEIC technologies is reviewed. Results obtained from transmission experiments using long wavelength OEIC's are described and applications for optical systems are discussed.     

Flexible optical waveguide film fabrications and optoelectronic devices integration for fully embedded board-level optical interconnects

This paper demonstrates a flexible optical waveguide film with integrated optoelectronic devices (vertical-cavity surface-emitting laser (VCSEL) and p-i-n photodiode arrays) for fully embedded board-level optical interconnects. The optical waveguide circuit with 45/spl deg/ micromirror couplers was fabricated on a thin flexible polymeric substrate by soft molding. The 45/spl deg/ couplers were fabricated by cutting the waveguide with a microtome blade. The waveguide core material was SU-8 photoresist, and the cladding was cycloolefin copolymer. A thin VCSEL and p-i-n photodiode array were directly integrated on the waveguide film. Measured propagation loss of a waveguide was 0.6 dB/cm at 850 nm.     

Coupled optoelectronic oscillators for generating both RF signaland optical pulses

We present experimental results of coupled optoelectronic oscillators (COEO) constructed with a semiconductor optical amplifier-based ring laser and a semiconductor colliding pulse mode-locked laser. Each COEO can simultaneously generate short optical pulses and spectrally pure radio frequency (RF) signals. With these devices, we obtained optical pulses as short as 6.2 ps and RF signals as high, in frequency, as 18.2 GHz with a spectral purity comparable with an HP83731B synthesizer. These experiments demonstrate that COEO's are promising compact sources for generating low jitter optical pulses and low phase noise RF/millimeter wave signals     

Bi-directional optical backplane bus for general purposemulti-processor board-to-board optoelectronic interconnects

We report for the first time a bidirectional optical backplane bus for a high performance system containing nine multi-chip module (MCM) boards, operating at 632.8 and 1300 nm. The backplane bus reported here employs arrays of multiplexed polymer-based waveguide holograms in conjunction with a waveguiding plate, within which 16 substrate guided waves for 72 (8×9) cascaded fanouts, are generated. Data transfer of 1.2 Gbt/s at 1.3-μm wavelength is demonstrated for a single bus line with 72 cascaded fanouts. Packaging-related issues such as transceiver size and misalignment are embarked upon to provide a reliable system with a wide bandwidth coverage. Theoretical treatment to minimize intensity fluctuations among the nine modules in both directions is further presented and an optimum design rule is provided. The backplane bus demonstrated, is for general-purpose and therefore compatible with such IEEE standardized buses as VMEbus, Futurebus and FASTBUS, and can function as a backplane bus in existing computing environments     

Ultraviolet photodetectors fabricated on natural-diamond substrates for optoelectronic systems

Spectral and current-voltage characteristics of photodetectors based on natural 2a-type diamond are studied. The long-wavelength sensitivity edge is discovered to shift with an increase in the nitrogen concentration. The conductivity of the detectors is estimated. It is shown that, for diamond photodetectors, both the photoresistive and photodiode operation principles can be implemented. A model of a diamond ultraviolet photoelectric converter with separation of nonequilibrium carriers in the space-charge region is proposed.     

Synthesis and optical properties of Ni-doped zinc oxide nanoparticles for optoelectronic applications

Nanocrystalline undoped and nickel doped zinc oxide (Zn1-xNixO, x=0.00, 0.01) powders are successfully synthesized by a simple and low-temperature "auto-combustion method". The microstructural and optical absorption and emission properties of the as-prepared samples are obtained using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red spectrometer (FTIR), UV-visible and photoluminescence (PL). The structure study confirms the formation of the hexagonal wurtz...     

Novel design procedure of broad-band multilayer antireflectioncoatings for optical and optoelectronic devices

A novel design procedure of broad-band multilayer antireflection (AR) coatings for optical and optoelectronic devices is proposed. The design algorithm is based on the optical admittance detuning, with the bandwidth of finite reflectivity as a new merit function. Coating structures consist of only two materials with nonquarter-wave thicknesses. Numerical mappings on the four-layer structure showed four optimizing regions where an optimized four-layer AR coating on 1.55 μm GaInAs-AlGaInAs MQW semiconductor laser facet was predicted to have a broad bandwidth of 106 mm for a reflectivity of less than 10^-5. TiO₂ and SiO₂ were electron-beam (EB) evaporated to form the four-layer AR coating on glass and InP substrates with an ion-beam assist and a real time in situ optical thickness monitor and experimentally verify its broad-band performance     

Electrical and optical properties of the three-terminaldouble-heterostructure optoelectronic switch

A theory is developed for the three-terminal version of the double-heterojunction optoelectronic switch (DOES), in which the third terminal, the injector, makes ohmic contact to the active layer of the device. The injector permits the biasing of the active-layer-substrate junction, the effect of which is to reduce the threshold voltage at which switching from the electrical and optical OFF-state to the ON-state occurs. Reverse baising the junction initiates switching from the ON- to the OFF-state. The current and optical output as a function of voltage with the injector current as a parametric variable are plotted in terms of the physical and geometrical properties of the device     

Integration of optical interconnects and optoelectronic elements on wafer-scale

The UV-reaction molding technology enabling for the fabrication of microoptical elements with rectangular, triangular or circular cross-sections (waveguides, prisms, lenses) in optical polymers is described. Multimode waveguide optical interconnects, coupling prisms and holding structures for fibers can be fabricated in one step. A three-dimensional monomode waveguide interconnection module is presented. Stability tests of the microoptical elements are reported.     

Silicon-based optical receivers in BiCMOS technology for advanced optoelectronic integrated circuits

A double photodiode (DPD) and a phototransistor were implemented in an industrial 0.8 μm bipolar complementary metal oxide semiconductor (BiCMOS) n-well process. Both devices are 100% BiCMOS compatible, so that no process modifications were necessary. A −3 dB bandwidth of more than 200 MHz was measured for the DPD. The rise and fall times of the photodiode are less than 1 ns. By an optimized antireflection coating layer for a wavelength of 638 nm a quantum efficiency of η=95%, which corresponds to a responsivity of R=0.49 A/W, is achievable. A phototransistor with a light-sensitive area of 53×53 μm² was developed. Its current amplification of B=300 results in a much larger responsivity compared to the photodiodes. Measurements have shown a −3 dB bandwidth of 7.8 MHz for the phototransistor.     

全光通信用关键光电子器件

近几年来，光纤通信在宽带网络 技术急速发展的推动和信息呈爆炸式增长需求的牵引下，发展速度比以往任何时候都更加迅猛。传统语音业务的年增长率只有５～１０％，而以Ｉｎｔｅｒｎｅｔ为代表的数据业务的年增长率却达到了２０－３０％。与传统的电话相比，Ｉｎｔｅｒｎｅｔ的最大特点不是人与人之间的一对一通信，而是人与机器（数据库）之间的一对Ｎ的通信。由于将全世界分散的数据库连接起来，使得整个网络中的信息量急剧增加。 另一方面，过去几年来，以ＤＷＤＭ为代表的宽带技术使系统带宽的增长比摩尔定律（约１８个月翻一番）还要快…     

光神经网络中的半导体光电器件

叙述了光神经网络的基本概念，并介绍了光神经网络中使用中的半导体光电器件， 体可调制光电检测器（ＶＳＰＤ），具有内存贮光神经芯片，人工视网膜芯片，以及不对称的Ｆａｂｒｙ－Ｐｅｒｏｔ调制器（ＡＦＰＭ）的最新研究结果。     

微机械加工技术与微传感器

传感技术的一个重要发展方向是传感器的微型化,微机械加工技术同昌硅微传感器的基础工艺技术,也是制作微执行器和微电子机械系统的基础工艺技术。本介绍微机械加工技术的概况以及采用微机械加工技术研制的几种微传感器。     

Low-noise current optoelectronic integrated receiver with internalequalizer for gigabit-per-second long-wavelength optical communications

An equalizer, which is essential in order to improve the sensitivity of receiver optoelectronic integrated circuits (OEICs) at a gigabit-per-second data rate, has been monolithically integrated on an InP substrate with a p-i-n photodiode and a high-impedance high-electron-mobility-transistor (HEMT) amplifier. The receiver operated up to 1.6 Gb/s and showed low noise current characteristics. The minimum noise current is less than 4 pA/√Hz. The sensitivity calculated from the noise current characteristics is -28.4 dBm for 1.6-Gb/s signals. The receiver chip, which was assembled on a ceramic mount, exhibited a sensitivity of -30.4 dBm at 1.2 Gb/s and 1.3-μm wavelength. The performance is as good as those of receiver OEICs with an external equalizer and sufficient for practical use in gigabit-per-second optical communication system     

An optoelectronic CMOS memory circuit for parallel detection andstorage of optical data

A CMOS static RAM (SRAM) circuit capable of detecting and storing optically transmitted data is described. Bits of data are transferred to the memory circuit via an array of parallel light beams. A 16-b optoelectronic SRAM was fabricated in a standard bulk CMOS process and tested using argon and helium-neon lasers. Data contained in an array of 16 light beams with an average power of 3.35 μW/pixel were successfully transferred to the SRAM in parallel fashion. The storage of the optical information was verified by electronically addressing each cell. The optical data transfer technology is extended to other systems in which high speed and parallelism are essential