A Tunable Miniaturized RF MEMS Resonator With Simultaneous High $Q$ (500–735) and Fast Response Speed $(

摘要

This paper reports on the design, fabrication, and measurement of a novel radio frequency (RF) microelectromechanical systems (MEMS) tunable all-silicon evanescent-mode cavity-based resonator that simultaneously achieves high quality factor and fast response speed. The resonator is based on a 1.5-mm-deep silicon-etched cavity attached to a gold-coated silicon substrate with an array of 75 185-$muhbox{m}$ -long 20-$muhbox{m}$-wide 1- $muhbox{m}$-thick gold beams. The 54- $hbox{mm}^{3}$ resonator is tunable from 15.2 GHz up to 16.5 GHz (analog tuning range) and up to 17.8-GHz range (digital tuning range) with an array of 75 MEMS fixed–fixed beams. The MEMS beams are biased against their own silicon substrate. This helps keep RF leakage at a minimum and permits high quality factors of 500–735 for the all-silicon configuration. By applying dynamic biasing waveforms, the MEMS tuners respond within 9 $muhbox{s}$ (actuation time) and 60 $muhbox{s}$ (release including settling time). To the best of the authors' knowledge, the presented resonator is more than 3 $times$ smaller, achieves nearly 30% higher average quality factor, and is at least 10–100$times$ faster than state-of-the-art resonators based on similar technology, implemented in similar frequency ranges.$hfill$ [2012-0122]