摘要
微纳机械谐振器因其具有超高的谐振频率、品质因子和灵敏度等优越特性,在物理传感、生物与化学检测、射频通信、能量收集等方面表现出了卓越的性能而备受关注,已成为当前微/纳机电系统领域的研究重点和热点之一.能量耗散一直以来都是制约微纳机械谐振器性能提升与应用发展的瓶颈问题,且耗散机制具有多样性、不确定性和尺度相关性.本文综述了微纳机械谐振器中的能量耗散机理与非线性阻尼效应的研究进展,主要针对热弹性阻尼、声子相互作用、黏性阻尼、支撑损耗、表面与界面损耗等内禀和外部耗散机制进行了综述,阐明了不同能量耗散的产生机理及影响规律,可为降低能量损耗和结构优化设计、提高谐振器件的品质因子和动态性能提供参考,对微纳机械谐振器的设计、制造及应用发展具有重要意义.
Advances in micro-and nanofabrication technologies have enabled the development of micro-and nano-mechanical resonators which have attracted significant attention due to their advantages of ultra-high resonance frequency, quality factor and sensitivity, and growing potential for physical sensing, biological and chemical detection, radio frequency communications and energy harvesting applications. It has become one of the emphases and hotspots in micro-and nano-electromechanical systems（MEMS/NEMS）. Energy dissipation is always the key problem and significant bottlenecks, which restricts its performance improvement and application development. Energy dissipation in a mechanical resonator represents the relaxation or loss of energy contained in a resonant mode to the external environment coupled to the resonator structure as well as to the other resonant modes. In micro-and nano-mechanical resonators, a key performance metric is the quality factor（Q）, which is the ratio of stored mechanical energy to the dissipated energy. Furthermore, energy dissipation has various and complicated mechanisms, which are uncertainty and scaling with system size. It is of great importance to understand the dissipation mechanisms. There exists a host of identifiable mechanisms, both intrinsic and extrinsic, which play an important role in the energy dissipation in micro-and nano-mechanical resonators. This article provides an overview on the progress of energy dissipation mechanisms and nonlinear damping effects in micro-and nano-mechanical resonators. Both intrinsic and extrinsic mechanisms, including thermoelastic damping, phonon interaction, viscous damping, support loss, surface and interface losses, are reviewed and discussed. The energy dissipation caused by viscous damping environments needs to be taken into account in initial design process. Different damping mechanisms are distinguished as the ambient air pressure varies based on the Knudsen number and various models for evaluating air damping mechanisms in different vibration structures from viscous flow regime to molecular flow mechanism have been paid more attention. Furthermore, the quality factor is limited by the thermal physics and specific energy loss mechanisms including thermoelastic, Akhieser, and Landau-Rumer damping in well-optimized designs of mechanical resonators. Support loss occurs because of the strain at the connection to the support structure and must be considered in order to understand the interaction and energy transmission between the resonator-support coupled systems. The support losses become detrimental as the resonator size is reduced but can be suppressed with appropriate device design. As the mechanical resonators become thinner or narrower, the surfaceto-volume ratio grows and the surface properties start to play a significant role in the dissipation. Understanding the effect of each mechanism is very important for their application in predicting adequately the quality factor and operation characteristics of micro-and nano-mechanical resonators. In addition, the mergence of nonlinear dissipation mechanisms becomes more and more important in predicting and determining the device performance and discerning the dominant contribution to energy dissipation in resonator devices. Specifically, it reveals the physical mechanisms and the methods of dissipation reduction used in each strategy and provides design guidelines for the development of high-performance resonators. The purpose of this review is to understand, sort, and categorize dominant energy dissipation sources and to determine their significance with respect to physics processes and engineering applications.
作者
张文明
闫寒
彭志科
孟光
ZHANG WenMing YAN Hart PENG ZhiKe MENG Guang(School of Mechanical Engineering, State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240, Chin)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2017年第19期2077-2093,共17页
Chinese Science Bulletin
基金
国家优秀青年科学基金(11322215)
霍英东青年教师基金(141050)
中组部青年拔尖人才计划资助
关键词
微/纳机电系统
微/纳机械谐振器
能量耗散
品质因子
非线性阻尼
micro/nano-electromechanical system
micro/nanomechanical resonator
energy dissipation
quality factor
nonlinear damping
