MEMS technology for timing and frequency control

An overview on the use of microelectromechanical systems (MEMS) technologies for timing and frequency control is presented. In particular, micromechanical RF filters and reference oscillators based on recently demonstrated vibrating on-chip micromechanical resonators with Q's >10,000 at 1.5 GHz, are described as an attractive solution to the increasing count of RF components (e.g., filters) expected to be needed by future multi-band wireless devices. With Q's this high in on-chip abundance, such devices might also enable a paradigm-shift in the design of timing and frequency control functions, where the advantages of high-Q are emphasized, rather than suppressed (e.g., due to size and cost reasons), resulting in enhanced robustness and power savings. With even more aggressive 3D MEMS technologies, even higher on-chip Q's have been achieved via chip-scale atomic physics packages, which so far have achieved Q's >10/sup 7/ using atomic cells measuring only 10 mm/sup 3/ in volume, consuming just 5 mW of power, all while still allowing Allan deviations down to 10/sup -11/ at one hour.