RF MEMS Resonators: Getting the Right Frequency and Q

Having recently been demonstrated at frequencies up to 1.9 GHz with Q's > 10,000 and record frequency-Q product of 2.75times10
¹³
exceeding those of quartz crystals, vibrating on-chip micromechanical resonators have now attained frequency and Q magnitudes needed by wireless RF front ends for both frequency filtering and generation. But, the performance of microresonators as building blocks in micromechanical signal processors such as filters and oscillators often relies more on the degree to which the manufacturing process can consistently achieve a set of specific RF frequencies and retain high Q's above a certain threshold. An overview on recent advances in vibrating RF MEMS technologies with focus on getting desired and repeatable frequencies and Q's is presented, followed by discussion of the key remaining issues and possible solutions for insertion into future wireless handsets.