RF MEMS Capacitors and Variable Capacitors Overview The most recent 4G devices are designed with specific emphasis on the data traffic challenge. Because there is an increasing number of bands, all the circuits and devices related to the design of wireless systems need to be enhanced including the power amplifiers, filters, and antennas. One of the very promising ways to enable this is to use tunable RF tunable devices based on microelectromechanical systems (MEMS) technology, and the RF MEMS variable capacitor (or switch) poses itself as a very strong candidate for this purpose. In fact, some commercial systems utilizing RF MEMS passive devices have already hit the market. Among the favorable characteristics of RF MEMS passive variable capacitance devices are linearity, low loss, high quality factor, and high capacitance ratio. The tutorial will discuss these figures of merit and also focus on the challenges that present themselves including seamless integration with CMOS, packaging, cost, and reliability. It is expected that RF/COMS engineers and designers of today will be working with RF MEMS engineers heavily in the near future, if they have not begun to do so already! In order for this interaction to be smooth, electronic engineers need to possess a thorough understanding of the MEMS technology and what it can offer; this tutorial will precisely fulfill this requirement. It is imperative that the electronic engineers of today acquaint themselves with the RF MEMS technology at an early stage to better plan for possible future trends in the wireless communication industry. Finally, and because the tutorial was designed in such a way that no prior MEMS knowledge is required, all audience, regardless of their backgrounds are welcome and encouraged to attend. The tutorial can be download from here. You are free to use this presentation as you see fit. Any publications, in the form of slides, conference papers, journal articles, technical reports, or otherwise, in which these slides will be used (in their original or modified format) should cite one or more of references below. For the developed tools, click here. Amro M. Elshurafa et al., "Low voltage puzzle-like fractal MEMS variable capacitor suppressing pull-in," IET/IEEE Micro & Nano Letters, Vol. 7, No. 9, pp. 965-969, 2012. Amro M. Elshurafa et al., "Differential RF MEMS Interwoven Capacitor Immune to Residual Stress Warping," IET/IEEE Micro & Nano Letters, Vol. 7, No. 7, pp. 658-661, 2012. Amro M. Elshurafa et al., "Two-Layer RF MEMS Fractal Capacitors in PolyMUMPS for S-Band Applications," IET/IEEE Micro & Nano Letters, Vol. 7, No. 5, pp. 419-421, 2012. Amro M. Elshurafa et al., "A Low Voltage RF MEMS Variable Capacitor with a Linear C-V Response," IET/IEEE Electronics Letters, Vol. 48, No. 7, pp. 392-393, 2012. Amro M. Elshurafa et al., "RF MEMS Fractal Capacitors with High Self Resonant Frequencies," IEEE JMEMS, Vol. 21, No. 1, pp. 10-12, 2012. Amro M. Elshurafa et al., "MEMS Variable Capacitance Devices Utilizing the Substrate: I. Novel Devices with Customizable Tuning Range," Journal of Micromechanics and Microengineering, Vol. 20, No. 4, 045027 (8pp), 2010. Amro M. Elshurafa et al., "Effects of Non-uniform Nanoscale Deflections on Capacitance in RF MEMS Parallel Plate Variable Capacitors," Journal of Micromechanics and Microengineering, Vol. 18, No. 4, 040512 (11pp), 2008. Amro M. Elshurafa et al., "Finite Element Modeling of Low Stress Suspension Structures and Applications in RF MEMS Parallel Plate Variable Capacitors,“ IEEE Transactions of Microwave Theory and Techniques, Vol. 54, No. 5, pp. 2211-2219, 2006.
