When radio frequency microelectromechanical system (RF MEMS) based switches appeared more than 25 years ago, micromechanics have attracted huge attention for enabling near-ideal microwave devices. Since then, MEMS switches and circuits went through different development stages and are currently proving themselves commercially. Micromachining technology has the potential to become an enabling technology for volume manufacturable microwave to millimeterwave systems. Although, reliability of MEMS devices is one of the prime challenge to meet present state-of-the-art performances due to occurrence of multiple failure modes after few cycles of operations. This reliability becomes more critical when multiple MEMS switches operate simultaneously like in a multi-bit digital phase shifters. Furthermore, MEMS based resonators has also attracted huge attention in present software defined cognitive radios and ultra-low-power autonomous sensor network radios. Fortunately, MEMS based resonators exhibit record on-chip Quality factor in RF oscillators and narrow bandwidth filters in RF channel selections. Vibrating MEMS is a potential candidate to realize in the RF front-end frequency gating spectrum analyzer. MEMS-based Oscillator is expected to benefit both the fundamental science (high-resolution mass sensors for physical, chemical and bio field) and industrial applications like PM2.5 sensors. More recently, MEMS-based thermal-piezoresistive oscillator demonstrates tremendous growth for real-time mass sensor with excellent mass resolutions and well suited to sense PM2.5 (~10 pg per particle). This seminar is divided into three subdomains. First phase primarily concentrates on the reliability improvements on MEMS based switching networks (up to single-pole-sixteen-thou) and different types of 4 to 5-bit phase shifters. It takes multiple iterations, extensive characterizations to conclude with a reliable MEMS digital phase shifters and given prime attention in this talk. Second phase briefly presents development of different RF channel select filters based on piezoelectric MEMS resonators for true software-defined cognitive radios. Third phase briefly shows the potential of MEMS oscillator using capacitive, piezoresistive MEMS resonators and demonstrates a real-time mass sensor utilizing a self-sustained thermal-piezoresistive oscillator. Finally, the seminar concludes with future research goals and teaching plans, followed by publication details.
Dr. Sukomal Dey received the B.Tech. degree in Electronics and Communication engineering from the West Bengal University Technology, Kolkata, India, in 2006, the M.Tech. degree in Mechatronics Engineering from the Indian Institute of Engineering Science and Technology, Shibpur, in 2009 and he did his one year master dissertation from the Central Electronics Engineering Research Institute, Pilani, India, in 2008- 2009. He obtained Ph.D. degree in Microwave Engineering from the Centre for Applied Research in Electronics (CARE), Indian Institute of Technology, Delhi in July, 2015. From Aug-2015 to July-2016, he was in the Collaborative Research Program, supported by Synergy Microwave Corporation, Paterson, NJ, USA, where he was a project scientist for the development of high reliable MEMS digital phase shifters and tunable filters. Aug-2016 to June-2018, he was working in the Institute of NanoEngineering and MicroSystems, National Tsing Hua University (NTHU), Taiwan, as a Post-Doctoral Research Fellow. Since June-2018, Dr. Dey is working in the Department of Electrical Engineering, Indian Institute of Technology, Palakkad as an assistant professor. His research interests include development of RF-MEMS devices and components for future RF front ends. Dr. Dey was a recipient of the Postgraduate Student Award from the Institute of Smart Structure and System, Bangalore, in 2012; the First Prize for Best Poster on ‘MEMS in Microwave’ in science day celebrations at IIT Delhi in 2015; the Best Industry Relevant Ph.D. Thesis Award from the Foundation for Innovation in Technology Transfer in 2016; the Distinction in Doctoral Thesis—2016 from Ph.D. Thesis Review Committee, IIT Delhi, in 2016; and the Postdoctoral Research Fellow Scholarships from the Ministry of Science and Technology (MOST), Taiwan in 2016 and 2017 respectively.