Voltage-controlled tuning to optimize MEMS resonator array-composite output power

A voltage controlled electrical stiffness tuning method has been demonstrated to correct phase and amplitude mismatches between the constituent resonators in a half-wavelength (λ/2) mechanically coupled array-composite towards maximizing its output power. Via tuning, a nine-disk array-composite using 3 output resonators achieves an output current 2.91× larger than that of a single one of its constituent resonators, and only a bit short of the 3× theoretical maximum. Without tuning, the array-composite achieves only 2.78× the current of a single device, and the deviation from ideal is expected to increase with the number of resonators in the array. The amount of tuning available can be tailored in numerous ways, from sizing of electrode-to-disk gap spacing, to specifying the number of devices in the array involved with tuning, to simple variation of voltages across selected electrode-to-resonator gaps. By raising the power output of a high-Q micromechanical disk-array composite resonator, the method and design of this work stand to greatly lower the phase noise of oscillators referenced to such devices.