InP-based integrated optical components

The possibilities of fabricating integrated optical components on an InP substrate are demonstrated by a number of devices that have been made in recent years. These components can have a major impact on evolving communication networks by facilitating new techniques for increasing capacity such as wavelength division multiplexing and soliton transmission.     

Monolithically integrated HgCdTe focal plane arrays

The cost and performance of hybrid HgCdTe infrared (IR) focal plane arrays are constrained by the necessity of fabricating the detector arrays on a CdZnTe substrate. These substrates are expensive, fragile, available only in small rectangular formats, and are not a good thermal expansion match to the silicon readout integrated circuit. We discuss in this paper an IR sensor technology based on monolithically integrated IR focal plane arrays that could replace the conventional hybrid focal plane array technology. We have investigated the critical issues related to the growth of HgCdTe on Si read-out integrated circuits and the fabrication of monolithic focal plane arrays: (1) the design of Si read-out integrated circuits and focal plane array layouts; (2) the low-temperature cleaning of Si(001) wafers; (3) the growth of CdTe and HgCdTe layers on read-out integrated circuits; (4) diode creation, delineation, electrical, and interconnection; and (4) demonstration of high yield photovoltaic operation without limitation from earlier preprocessing such as substrate cleaning, molecular beam epitaxy (MBE) growth, and device fabrication. Crystallographic, optical, and electrical properties of the grown layers will be presented. Electrical properties for diodes fabricated on misoriented Si and readout integrated circuit (ROIC) substrates will be discussed. The fabrication of arrays with demonstrated I–V properties show that monolithic integration of HgCdTe-based IR focal plane arrays on Si read-out integrated circuits is feasible and could be implemented in the third generation of IR systems.     

Monolithically integrated grating cavity tunable lasers

A novel grating cavity tunable laser is proposed and experimentally demonstrated. It is realized by monolithically integrating a semiconductor optical amplifier, a dispersive element, a phase-control section, and an etched diffraction grating in a single chip. Tuning operation is based on electrically controlled beam deflection provided by dispersive element and phase matching by phase-control section. With the electrical control, the wavelength tuning of 8.5 nm with a sidemode suppression ratio of about 35 dB has been successfully achieved.     

Monolithically integrated multiwavelength grating cavity laser

A multiwavelength grating cavity laser is reported using a novel design for a multichannel light source based on an etched diffraction grating. Following the design, the compact eight-channel device capable of fine-tuning has been realized by monolithically integrating semiconductor optical amplifiers, various passive waveguides, and deeply etched grating, providing high butt-coupling efficiency, and low waveguide losses. As a result, the sidemode suppression ratio in excess of 45 dB over all channels was achieved.     

Monolithically integrated tunable laterally coupleddistributed-feedback lasers

A new method for fabrication of tunable InGaAsP-InP single-mode lasers without epitaxial overgrowth is reported. These devices show the advantage of a considerably simplified fabrication process compared to conventional tunable laser types. The lasers comprise an active Bragg reflector integrated with an uncorrugated separately pumped gain region. By adjusting the current through the Bragg reflector, the wavelength can be tuned between 1590.8 and 1595.2 nm     

First InP-based reconfigurable integrated add-drop multiplexer

A four-channel reconfigurable integrated add-drop multiplexer on InP-substrate is reported. The device consists of a 5/spl times/5 PHASAR demultiplexer integrated with Mach-Zehnder interferometer electrooptical switches. Total device size is 3/spl times/6 mm/sup 2/. All routing configurations of four wavelengths have been demonstrated. Crosstalk values are better than -20 dB. On-chip loss for the dropped or added signals and for the signals coupled from the input to the output port are lower than 7 and 11 dB, respectively.     

单片集成电吸收调制分布反馈激光器

提出一种选择区域外延双有源区叠层(SAG-DSAL)结构新技术,基于此技术设计研制了单片集成电吸收调制激光器(EML),SAG-DSAL-EML管芯的阈值电流为20mA,工作电流为100mA时的出光功率为10mw,由吸收调制器(EAM)加-3V偏压时的消光比为12dB,实现了简化制作工艺并提高器件性能的预期目的,有望用...     

Monolithically integrated Gunn oscillator at 35 GHz

A fully planar monolithically integrated Gunn oscillator for 35 GHz has been constructed on a GaAs substrate. An output power of about 1.5 mW, corresponding to an efficiency of 0.5%, is obtained from the oscillator in its present unoptimised form. The device is intended for use as a local oscillator in integrated millimetre-wave receivers. Measurements are made by means of quasi-optical output coupling.     

Monolithically integrated array of GaAlAs electroabsorption modulators

The operation of an eight-element monolithic array of GaAlAs electroabsorption modulators has been demonstrated. The single-mode waveguide modulators are implemented in a reverse-biased p-?-n heterojunction configuration, with centre-to-centre spacing of 9 ?m between adjacent channels. This device may be useful for intensity modulation in high (spatial) resolution applications.     

Monolithically integrated InGaAs/InP PIN-JFET photoreceiver

A vertically integrated InGaAs/InP PIN-JFET has been fabricated, in which separate layers are used for the FET channel and PIN intrinsic region. The maximum transconductance was 170 mS/mm, which is the highest reported figure for an integrated structure, and the photodiode quantum efficiency was 64% at ?5 V and 1.53 ?m wavelength, without antireflection-coating.     

High-speed monolithically integrated silicon photoreceivers fabricated in 130-nm CMOS technology

A complementary metal-oxide-semiconductor (CMOS) monolithically integrated photoreceiver is presented. The circuit was fabricated in a 130-nm unmodified CMOS process flow on 2-/spl mu/m-thick silicon-on-insulator substrates. The receiver operated at 8 Gb/s with 2-dBm average input optical power and a bit error rate of less than 10/sup -9/. The integrated lateral p-i-n photodetector was simultaneously realized with the amplifier and had a responsivity of 0.07 A/W at 850 nm. The measured receiver sensitivities at 5, 3.125, 2, and 1 Gb/s, were -10.9, -15.4, -16.5, and -19 dBm, respectively. A 3-V single-supply operation was possible at bit rates up to 3.125 Gb/s. The transimpedance gain of the receivers was in the range 53.4-31 dB/spl Omega/. The circuit dissipated total power between 10 mW and 35 mW, depending on the design.     

A compact integrated InP-based single-phasar optical crossconnect

The first integrated InP-based polarization independent optical crossconnect is reported. The device can crossconnect signals at four wavelengths independently from two input fibers to two output fibers. Total on-chip loss is less then 16 dB. Device size is 7×9 mm²      

V频段小型化集成接收前端技术

V频段小型化集成接收前端主要实现对V频段毫米波信号的低驻波、低噪声接收和产品小型化。采用多功能芯片与混合集成技术,实现了毫米波接收信道的小型化集成。引进了微带正交耦合器,构成平衡式分布放大优化射频接收端口输入驻波系数的设计思路,替换了体积笨重的波导宽带隔离器,减小了毫米波接收前端体积和重量。通过对V频段波导微带过渡探针的容错性设计,降低了V频段毫米波接收前端的组装难度,提高了接收前端的一次组装合格率。最终实现批量化V频段小型化集成接收前端射频的输入驻波系数优于1.6,噪声系数优于4.2 dB,外形尺寸(含插座)33.4 mm×30 mm×12 mm。     

Monolithically integrated InGaAsP/InP composite-cavity distributedfeedback lasers

Linewidth reduction to 1 MHz for monolithically integrated extended-cavity DFB lasers that are designed to achieve high optical coupling to a low-loss extended cavity is described. Since a high-efficiency extended cavity at the same time degrades the frequency-modulation (FM) response, an active gain section is integrated at the end of the extended cavity, and its use as a modulator section that maintains a flat FM response at 0.7 GHz/mA is shown. The linewidth and FM characteristics of this DFB extended-passive/active-cavity laser are compared to those of the conventional DFB extended-passive-cavity laser and a two-section DFB laser     

Monolithically integrated polarisation-insensitive high-speedbalanced mixer receiver on InP

A monolithically integrated high-speed balanced mixer receiver on InP is presented for the operation at 1.55 μm wavelength. The detector provides cutoff frequency of 14 GHz and polarisation-insensitive common-mode rejection ratio of better than -20 dB     

Monolithically integrated multichannel SiGe/Si p-i-n-HBTphotoreceiver arrays

A low-power, short-wavelength eight-channel monolithically integrated photoreceiver array, based on SiGe/Si heterojunction bipolar transistors, is demonstrated. The photoreceiver consists of a photodiode, three-stage transimpedance amplifier, and passive elements for feedback, biasing and impedance matching. The photodiode and transistors are grown by molecular beam epitaxy in a single step. The p-i-n photodiode exhibits a responsivity of 0.3A/W and a bandwidth of 0.8 GHz at λ=0.88 μm. The three-stage transimpedance amplifier demonstrates a transimpedance gain of 43 dBΩ and a -3 dB bandwidth of 5.5 GHz. A single channel monolithically integrated photoreceiver consumes a power of 6 mW and demonstrates an optical bandwidth of 0.8 GHz. Eight-channel photoreceiver arrays are designed for massively parallel applications where low power dissipation and low crosstalk are required. The array is on a 250-μm pitch and can be easily scaled to much higher density. Large signal operation up to 1 Gb/s is achieved with crosstalk less than -26 dB. A scheme for time-to-space division multiplexing is proposed and demonstrated with the photoreceiver array     

Monolithically integrated, photoreceiver with large, gain-bandwidth product

A direct-detection 800 nm GaAs monolithically integrated photoreceiver is reported with a photocurrent gain of 200 and a 1 GHz bandwidth capable of driving a 50 ? load with IV peak pulses. The integrated NPN photodiode has over 7GHz bandwidth and requires no modifications to the ion-implanted GaAs MESFET process. The 200GHz gain-bandwidth product and 3200 V/W responsivity are among the highest reported for similar receivers.     

Monolithically integrated optical channel monitor for DWDM transmission systems

The design, fabrication, and performance of an InP-based monolithically integrated optical power monitor are presented. It contains 44 wavelength channels separated by 100 GHz and demonstrates record small footprint size. The device's major components, which include the echelle diffractive grating demultiplexer, passive waveguide circuitry and single-mode vertically integrated waveguide PIN photodetectors, are characterized and discussed as generic building blocks of InP-based planar lightwave technology for DWDM.