Presentation Information
[23p-12E-6]Air Damping Effect on Quality-Factor in High-Order Resonance Modes of Single-Crystal Diamond Microcantilevers
〇(DC)Guo Chen1,2, Zilong Zhang1, Keyun Gu1, Liwen Sang1, Satoshi Koizumi1, Yasuo Koide1, Zhaohui Huang2, Meiyong Liao1 (1.National Institute for Materials Science, 2.China University of Geosciences (Beijing))
Keywords:
single-crystal diamond,MEMS cantilever,energy dissipation
Single-crystal diamond (SCD) for micro/nanoelectromechanical systems (MEMS/NEMS) has attracted a lot of interest because of their numerous outstanding properties, such as the highest Young’s modulus, the highest thermal conductivity, and low intrinsic dissipation. Resonant cantilevers with high-frequency and high-quality (Q) factors hold great promise for high-sensitivity and high-resolution sensors. Under practical use, resonators are always operated in atmospheric air, and this environment significantly impacts their Q-factor in comparison to vacuum conditions. For MEMS cantilevers, air damping is very pronounced, particularly in the fundamental resonance mode. However, the resonant behavior in high-order modes of SCD cantilevers against pressures has not been reported yet. In this work, we fabricated diamond cantilevers and investigated the effect of gas atmosphere on Q-factor in high-order resonance of SCD MEMS cantilevers. The Q-factor of the high-order modes is found to be nearly constant up to pressures between 10-4 to 100 Pa and then decreases to less than 1,000 in 103 Pa, similar to the fundamental mode. Compared to the high-order modes, the first mode has higher Q-factors in vacuum (intrinsic regime). Nevertheless, the high-order modes in the molecular and viscous flow regimes (P > 101 Pa) exhibit higher Q-factors than the fundamental mode. Hence, in low-vacuum and atmospheric environments, the high-order resonance modes provide a profound sensitivity improvement for MEMS sensing devices, attributed to the much higher f·Q product.