Silicon Waveguide Integrated Technologies for Intelligent Millimeter-wave/Terahertz Micro-Systems

位于无线电频率和光波之间，毫米波(mmW)/太赫兹（THz）电磁波频谱（特别是0.1到3太赫兹）具有两种频谱最理想的特性。像无线电波一样，毫米波/太赫兹波可以穿透不透明的物体，同时提供与光波相当的几何分辨率。这种独特的特性使超宽带通信（毫米波卫星通信、5G及以上）、高分辨率雷达（未来的汽车雷达）、安全成像、生物医学/制药材料表征和射电天文学等领域的广泛新应用成为可能。***尽管该频率范围具有独特的优势，并且毫米波商用（CMOS, SiGe）纳米级半导体技术取得了令人印象深刻的进步，但缺乏具有合理性能的高效毫米波/太赫兹有源器件，以及现有无源器件的成本和复杂性以及缺乏合适的集成技术平台阻碍了该频谱的快速工业规模使用。***虽然低成本毫米波/太赫兹有源器件技术要实现大规模市场应用还有很长的路要走，但高效、低插入损耗的无源器件和天线以及低成本集成技术可以在很大程度上弥补有源器件效率和灵敏度的不足，以及它们的噪声行为。***目前用于射频/微波频率范围的平面多层电路和天线技术不适用于毫米波/太赫兹系统，因为金属和常见的商用级软基板的插入损耗大。目前，100+ GHz波段的主流波传输/处理技术是金属波导及其变体，它们体积大、重量重、成本高，特别是在太赫兹波段，几乎没有集成的可能性。这已经成为实现毫米波/太赫兹集成化低成本商用产品的主要瓶颈。作为解决这一问题的一种全新方法，申请人小组在过去的8年里一直在研究和开发一种新的基于硅的集成波传输/处理/发射技术平台。新的技术平台是基于硅波导在玻璃或硅衬底在毫米波/太赫兹频率范围。这项研究已经产生了一个成熟的技术平台和几个新颖的设计概念，如毫米波/太赫兹传感器和具有波束控制能力的天线阵列。***提出的研究的主要目的是研究在开发的基于si的平台中最具成本效益的系统（电路/天线/封装）集成技术。拟议计划的主要重点是有源器件的集成，包括传统的和新型的，如石墨烯，以及用于新兴毫米波/太赫兹通信系统、成像和传感的模块化大规模集成智能微系统的开发。********

Sitting between the radio frequencies and light-waves, millimeter-wave (mmW)/Terahertz (THz) spectra of electromagnetic waves (particularly 0.1 to 3 THz) have the most desirable properties of both spectra. Like radio waves, mmW/THz waves can penetrate into opaque objects and, at the same time, provide geometrical resolution only comparable to that of the light-waves. Such unique characteristics have enabled a wide range of new applications in ultra-broadband communication (mmW satellite communication, 5G and beyond), high resolution radar (future automotive radars), security imaging, biomedical/pharmaceutical material characterizations, and radio astronomy.*** Despite unique advantages of this range of frequencies and impressive advances in mmW commercial (CMOS, SiGe) nano-scale semiconductor technologies, lack of efficient mmW/THz active devices with reasonable performance, as well as the cost and complexity of the existing passive devices and the lack of a suitable integration technology platform has hindered fast industrial scale usage of this spectrum.*** Although there is still a long way to low-cost mmW/THz active device technologies for mass market applications, highly efficient and low insertion loss passive devices and antenna and low-cost integration technologies can, to a large extent, compensate for the active devices lack of efficiency and sensitivity, as well as their noisy behavior. *** Current planar multi-layer circuit and antenna technologies for RF/microwave range of frequencies are not applicable to mmW/THz systems due the large insertion loss of metals and common commercial grade soft substrates. Currently, the mainstream technique for wave transmission/processing at 100+ GHz is metallic waveguide and its variations, which are bulky, heavy, and quite costly, particularly at THz, with almost no possibility of integration. This has become a major bottleneck for realizing integrated mmW/THz commercial products at low cost.*** As a fundamentally new approach to this problem, the applicant group has been investigating and developing a novel Si-based technology platform for integrated wave transmission/processing/emission, over the past 8 years. The new technology platform is based on Si-waveguide on glass or Si substrate at mmW/THz range of frequencies. This research has resulted in a proven technology platform and several novel design concepts such as mmW/THz sensors and antenna arrays with beam control capability.*** The main objective of the proposed research is to investigate the most cost-effective system (circuit/antenna/package) integration technologies in the developed Si-based platform. Major foci in the proposed program are integration of the active devices, both conventional and new ones such as graphene and development of modular large scale integrated intelligent microsystems for emerging mmW/THz communication systems, imaging, and sensing.********