Electrical actuation of single-crystal diamond MEMS resonators at high temperatures

Achieving efficient low-voltage actuation of microelectromechanical system (MEMS) resonators in high-temperature environments poses a difficult topic due to the thermal interference and the risk of high-temperature failure. In this work, the single-crystal diamond (SCD) resonators fabricated through the ion implantation-assisted lift-off (IAL) technique exhibit a SCD-on-SCD cantilever structure. We propose an electrical actuation system based on the electrostatic effect specifically designed for SCD MEMS resonators with a low radio-frequency amplitude of similar to 100 mV. The SCD resonators demonstrate stable and efficient actuation across a wide temperature range, from room temperature to 500 degrees C. Importantly, the actuation voltage exhibits little impact on the resonance frequency and the Q factor of the resonator. The SCD resonator showcases exceptional thermal stability in resonance frequency, with a low temperature coefficient of frequency (TCF) below -12 ppm/degrees C up to 500 degrees C. The developed actuation scheme holds tremendous potential as a robust platform for realizing SCD MEMS devices, particularly in applications requiring high integration at high temperatures. An electrical actuation system harnessing the electrostatic effect is showcased for SCD MEMS resonators. In this setup, the electrode on the resonator is grounded, while the electrode on the SCD substrate, connected to an RF signal, is utilized to actuate the motion of the resonator. Notably, the SCD resonators exhibit reliable and efficient actuation across a wide temperature range, from room temperature to 500 degrees C.