Differential silicon micro-resonant pressure sensor based on electrostatic excitation piezoresistance detection

Abstract

The invention discloses a differential silicon micro-resonance type pressure sensor based on electrostatic excitation piezoresistance detection. The differential silicon micro-resonance type pressuresensor comprises a resonance beam, a coupling beam, a vibration pickup beam, a fixed electrode, a movable electrode, a mass block, a movable anchor point, a fixed anchor point and a silicon island, wherein the movable anchor point is fixedly connected with the pressure sensitive film through using the silicon island; when the pressure sensitive film is deformed by a load, the movable anchor pointconnected with the pressure sensitive film is driven, then the movable anchor point drives the resonance beam to deform, such that the internal stress of the resonance beam is changed, the vibration frequency of the resonator is changed, the vibration frequency of the resonance beam is measured by means of a piezoresistor on the vibration pickup beam, and the vibration pickup beam and the couplingbeam adopt a special design method, so that the vibration pickup beam generates straight pulling and straight pressing acting force when the resonator is in a working mode, and the amplitude of the resonance beam can be linearly output through using a Wheatstone bridge.

Description

technical field [0001] The invention belongs to the technical field of micro-nano electronic sensors, and in particular relates to a differential silicon micro-resonant pressure sensor based on electrostatic excitation piezoresistive detection. Background technique [0002] Silicon micro-resonant pressure sensor is the pressure sensor with the highest precision at present. It measures the pressure indirectly by detecting the natural frequency of the resonant structure, and it is a quasi-digital output. Its accuracy is mainly affected by the mechanical properties of the mechanical structure, so it has strong anti-interference ability and stable performance. At the same time, silicon resonant pressure sensors also have the advantages of wide frequency band, compact structure, low power consumption, small size, light weight, and mass production, and have always been the focus of research by scientific research institutions in various countries. Silicon microresonant pressure s...

AI Technical Summary

Problems solved by technology

Single-resonator mode silicon microresonant pressure sensors are very susceptible to temperature and package stress, which reduces the output accuracy of the sensor and the sensor has low sensitivity

Through literature search, there are few literatures on the dual resonator differential design and compensation of silicon microresonant pressure sensors with electrostatic excitation and piezoresistive detection.

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