Micromechanical Resonant Displacement Gain Stages

Micromechanical resonant displacement gain stages have been demonstrated that employ directionally engineered stiffnesses in resonant structures to effect displacement amplification from a driven input axis to an output axis. Specifically, the introduction of slots along the output axis of a 53-MHz wine-glass mode disk resonator structure realizes a single gain stage with a measured input-to-output displacement amplification of 3.08 x. Multiple such mechanical displacement gain stages can then be cascaded in series via half-wavelength beam couplers to achieve multiplicative gain factors; e.g., two cascaded gain stages achieve a total measured gain of 7.94 x. The devices have also been operated as resonant switches, where displacement gain allows impact switching via actuation voltages of only 400 mV, which is 6 x smaller than for previous reso switches without displacement gain. The availability of such high frequency displacement gain strategies for resonant switches may soon allow purely mechanical periodic switching applications (such as power amplifiers and power converters) with much higher efficiencies than current transistor-based versions.