【作者】 余志华；

【导师】 罗风光；

【作者基本信息】 华中科技大学 ， 光电信息工程， 2010， 博士

【摘要】 随着通信和计算机技术等信息科学技术的发展,特别是近几年来高速信息通信网的飞速发展,要求计算机处理速度向着每秒千亿次、万亿次甚至更快的高性能计算机方向发展。而传统电互连技术的性能由于固有的物理原因而受到限制,已越来越不适应高速信息处理与传输的要求。因此,光互连技术的研究越来越受到国内外研究者的重视,以高速率的光互连技术取代目前计算机中所采用的铜导线,以光子而不是电子为媒介,在芯片间之间实现高密度、高速传输数据。本文的研究对象为基于波导的芯片间光互连网络,首先从Maxwell方程出发,分析阶跃型平板波导中的波动方程以及场分布的解的形式和相关参量。由于方程的解析解难以确定,引入有限差分光束传输法,详细推导出FDBPM求解光在波导中传输的过程,并用它在Matlab上来实现光波导器件的设计和仿真。其次提出一种新型的PCB上芯片间光互连的基本结构,主要包括：VCSEL激光器、波导耦合器、内置光波导和光接收器;光互连层是其实现的关键,充分利用有限差分光束传输法来设计和分析光互连层。对所设计的矩形多模光波导仿真分析显示,其传输效率将大于99%。接下来,系统研究光波导的制备工艺,通过实验摸索,总结出一套刮刀法制作光波导的工艺流程,主要包括模具制作和波导制作两个部分,它具有步骤简单,易于控制波导芯层尺寸,适合制作大尺寸波导等突出优点。然后,对制作出的波导样品进行了通光测试和波导损耗测试,结果表明,其各路波导的平均损耗大概在3dB左右,符合通信要求。最后针对芯片间互连网络特点,分别设计了三种不同的网络模型：基于弯曲波导的全连接光互连网络、基于光开关阵列的全光交换互连网络和基于Mesh的光电混合互连网络。通过分析各自特点,选用最后一种方案,并在PCB板上成功制作出基于2×2 Mesh的光互连网络演示系统。它采用阵列式VCSEL/PIN垂直腔表面发射并行光发射／光接收模块,通过PCB板中光波导层进行光信号传输。对该系统进行全面测试表明：系统成功实现芯片间MESH网络的上移、下移、左移、右移光互连功能,光波长850m,单通道速率3.125Gbit/s,误码率低于10-16,完全满足通信要求。总之,成功实现了一种基于光波导的芯片间光互连网络,它将光互连层引入到常规电路板中,克服了电路板上芯片间电互连的高速瓶颈,具有创新性,对发展宽带、高速、大容量信息通讯网和高性能计算机并行处理和传输系统,具有重要的现实意义和应用前景。更多还原

【Abstract】 Recently, with the development of information technoledge, such as telecommunications and computers, computers’processing speed was required to hundreds of billions per second or even trillions times per second, especially in high-speed information networks. But the performance of conventional electrical interconnection technology, because of the inherent physical restrictions, has become more and more unsuitable for high-speed information processing and transmission requirements. As a result, domestic and foreign researchers pay more attantion to optical interconnection technology aiming to replace the traditional copper wire interconnects, with photons rather than electronic as a medium, to realize high-density, high-speed communtions between chips.This paper focuses on waveguide-based interchip optical interconnection network. Firstly, from the Maxwell equation, the step-index planar waveguide were analyzed to get its wave equation, field distribution and related parameters. As the equation could not be solved exactly, we introduced finite difference beam propagation method (FDBPM) and derived it in detail for light transmitting in waveguides. And with it, we realized the design and simulation of optical waveguide devices in Matlab.Then, we proposed a new chip-to-chip optical interconnect structure on PCB, including VCSEL laser, waveguide coupler, embedded optical waveguide and optical receivers. The optical interconnect layer is the key to its implementation. So we designed and analyzed the optical interconnect layer in FDBPM, and the simulation of rectangular multi-mode waveguide in Matlab shows that the transmission efficiency would be greater than 99%. Next, the production process of waveguide was discussed, and through experiments, we summed up a new waveguide fabrication process named doctor bladding, that mainly includes two steps:mold-making and waveguide-making. The whole fabrication process was simple and easy to control for the size of waveguide core, suitable for making large-size waveguides and other prominent advantages. Then, the samples of waveguide fabricated were tested and results showed the average waveguide loss was about 3dB, that would be enough to meet the communication requirements.Finally, according to the characteristics of the interchip interconnection network, we designed three different network models:fully-connected network based of bending waveguide, all-optical switch interconnection network based of optical switch array and mesh-based opto-electronic hybrid connected network. By analyzing their own characteristics, the third option was chosen. We successfully fabricated a 2x2 Mesh-based optical interconnection network for demonstrations, which included parallel optical transmitter /receiver module-VCSEL/PIN array, and realized the optical signal transmitting in waveguides embedded in PCB. Experiments confirmed that each node of this network could realized to move up, down, left, right, the light’s wavelength was 850nm, the data rate in each channel could reach above 3.125 Gbps and the bit error rate (BER) could be up to 10-16, which would be enough to satisfy communications.In a word, a new interchip waveguide-based optical interconnection network, with a conventional optical interconnection layer in printed circuit boards, was designed and realized, which could overcome the bottleneck of high-speed electrical interconnecs. It would be a innovation and could have important practical significances and applications to the development of broadband, high-speed, large-capacity information communication networks and parallel processing and transmission of high-performance computer systems.更多还原