A New Silicon-Based Dielectric Waveguide Technology for Millimeter-Wave/Terahertz Devices and Integrated Systems
Safieddin Safavi-Naeini and Mohamed Basha (Systems Design)
In recent decades, the millimeter-Wave (mmWave)/THz band has attracted great attention in the research community. The Terahertz frequency range has traditionally been considered as the RF "no man's land", between electronic and optic technologies. Many efforts have been made to extend existing active and passive devices to take advantage of these higher frequencies. The terahertz (THz) region of electromagnetic spectrum has been subject to extensive research activities due to its unique advantages for a vast number of applications in wireless communication, radar, physics, chemistry, imaging, biology, radio astronomy, and medicine.
This seminar presents a novel silicon waveguide-based platform for implementing various devices in the mmWave and THz range of frequencies. The structures introduced in this study are designed based on High Resistivity Silicon (HRS). Two technologies are developed and investigated at the Centre for Intelligent Antenna and Radio Systems (CIARS): Silicon-On-Glass (SOG) and Silicon Image Guide (SIG) platforms. The proposed technologies provide a low-cost, highly efficient, and integratable platform for implementing a variety of mmWave/THz systems suitable for various applications such as sensing, communication, and imaging. Extensive design and error analysis are conducted to evaluate the performance of two developed silicon waveguide technologies, SIG and SOG. The possible fabrication and measurement setup errors/uncertainties of the proposed silicon technologies are comprehensively studied. Also, the loss characteristics of both proposed platforms are experimentally assessed. Furthermore, a newly developed laser machining technique is explained in detail. The developed in-house laser machining technique is a fast, mask-free, and chemical-free fabrication method for realization of SIG structures.
Also, a number of building-block mmWave/THz passive components based on SIG technology are designed, fabricated, and successfully tested with desired performance at mmWave range of frequencies. In this seminar three major passive components are discussed: bends, dividers, and couplers. Also, three types of dielectric antennas are designed and optimized based on the SIG technology: parasitic tapered antenna, groove grating antenna, and strip grating antenna.
Last but not least, a number of resonance structures, operating at Whispering Gallery Modes (WGMs), are introduced and discussed. Located between the mmWave and optics, THz frequencies can be used for interfacing between optic and electronic systems. In short, the future belongs to THz. THZ technologies open new market opportunities for a vast range of applications. Finally, the universe and the cosmic background are inherently surrounded by Terahertz radiation and that is why THz has received much attention for investigation of our galaxy and the Big Bang. THz has therefore become the most exciting area of research and development in RF technologies with exciting promises for many future generation systems and emerging applications.