Mechanically corner-coupled square microresonator array for reduced series motional resistance

Abstract

Substantial reductions in vibrating micromechanical resonator series motional resistance R/sub x/ have been attained by mechanically coupling and exciting a parallel array of corner-coupled polysilicon square plate resonators. Using this technique with five resonators, an effective R/sub x/ of 4.4 k/spl Omega/ has been attained at 64 MHz, which is more than 4.8 X smaller than the 21.3 k/spl Omega/ exhibited by a stand-alone transverse-mode square resonator, and all this achieved while still maintaining an effective Q>9,000. This method for R/sub x/-reduction is superior to methods based on brute force scaling of electrode-to-resonator gaps or DC-bias increases, because it allows a reduction in R/sub x/ without sacrificing linearity, and thereby breaks the R/sub x/ versus dynamic range trade-off often seen when scaling.