Sensor for self-testing self-oscillation of resonant-type tiny cantilever beam

Abstract

A self-detection transducer of self-excitation oscillation on resonant micro-cantilever beam is prepared for forming closed loop circuit by series-connecting frequency-selection network, filter amplification circuit, phase compensation circuit with driving circuit; forming frequency-selection network by micro-cantilever beam, compensation circuit, operation- amplification circuit, the first and the second feedback circuits; connecting bottom electrode to negative input end of operation amplification circuit and top electrode to positive input end of operation amplification circuit through compensation circuit.

Description

technical field [0001] The present invention relates to the field of resonant micro-electromechanical system (MicroElectroMechanical System) cantilever sensor, and specifically relates to the resonant frequency detection type MEMS micro-cantilever sensor technology, and related MEMS micro-cantilever self-excited oscillation self-detection resonance frequency technology and method . Background technique [0002] With the development of MEMS technology, MEMS microsensors have the characteristics of small size, light weight, fast response, low power consumption, low cost, easy array integration, etc., and are more and more widely used in various fields of production and life. There is a large class of MEMS sensors that belong to the resonant sensor. The MEMS structure enters the resonance state under the excitation of the natural frequency, and the change of the physical quantity of the external environment will change the natural frequency of the system, thereby causing the re...

AI Technical Summary

Problems solved by technology

[0004] The use of two sets of independent structures for driving and detecting makes the sensor structure more complicated and the process flow increases accordingly. For the uncommercialized MEMS process technology, this reduces the stability of the system and the yield of the microstructure, greatly Increased cost; on the other hand, two energy conversions from electrical signals to mechanical frequency signals and then from mechanical frequency signals to electrical signals increase the loss of the system and reduce the reliability of the system

In short, the sensor system is complex, susceptible to interference, and loss increases, seriously affecting the performance and stability of the sensor system, and increasing the difficulty and cost of sensor manufacturing, hindering the application and development of resonant MEMS microsensors

However, if the two independent structures of drive and incentive are combined into one, the above problems can be well avoided. There is no report on this aspect yet.

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