Research On Resonance Characteristic Of Silicon Micro Resonator Under Abnormal Environment

With the commercialization of micro devices, abnormal working condition becomes key factor that affects the acquisition of high precision and reliability of micro devices. Since the microresonator is the core component of these microstructures, research on its resonant characteristics in abnormal working condition becomes more and more important. Therefore with micro resonator as the research object, in this thesis, temperature-sensitive and damping-sensitive resonator structures are designed first. Then, the temperature variation regularity of resonance frequency of micro resonator and the relationship between system damping and vacuum from theoretical derivation are verified from the perspectives of modeling simulation and experimental validation. The main content consists of the following:1) The typical temperature coefficient model of the natural frequency and the temperature-sensitive parameters of support beam are briefly described and summarized. Then, the regularity mechanism of the influence of temperature on the natural frequency of support beam is analyzed. With the above mechanism and regularity as a design goal, the structure parameters of typical support beam are simulated. The simulation results show that affected by environmental temperature, resonance frequencies of clamped-clamped beam, crab-leg beam and folded beam increases with the decrease of temperature linearly. Morerover, the bigger the rigidity of the beam is, the higher its temperature sensitivity is. And the stress relief capacity of folded beam is comparatively the best.2) After the analysis of energy loss of resonator in different vacuum, a theoretical model of quality factor and vacuum degree is established, with investigation plans being made. Then different resonators with different quantity of damping tooth are designed. Meanwhile, analysis results demonstrate that the quality factor decreases with increasing vacuum degree. And energy loss of resonator mainly stems from air damping in low vacuum, while it stems from anchor loss, material loss, etc. in high vacuum.3) Based on the structural characteristics of the designed resonator, the whole processing procedure is planned. And the research on relevant key process is accomplished to realize the preparation of temperature sensitive and damping sensitive structures.4) The temperature test platform is established and tests of typical temperature sensitive structure and temperature sensitivity are completed. The tests indicate that change tendency of temperature sensitive structure is approximately consistent with simulation result. And by analyzing the finite element simulation and process error, it is found that the error between experiments and simulations is primarily derived from etching processing, variation of clamped beams and random error of test environment.5) With a home-made vacuum test platform, the curve reflecting the relationship between quality factor of damping structure and vacuum degree is acquired. Then it is found that theoretical result coincides with experimental result in low vacuum by comparison. And the quality factor of resonator decreases with the increment of damping tooth and width of support beam.