Probe type high-accuracy force sensor based on quartz resonator

Abstract

The invention discloses a probe type high-accuracy force sensor based on a quartz resonator. The force sensor comprises a probe, wherein the probe is connected with the input end of a second-order enlargement beam; the second-order enlargement beam is connected with a silicon substrate frame through four supporting point beams; the output end of the second-order enlargement beam is fixedly connected with one end of a quartz tuning fork beam by organic adhesive; the quartz tuning fork beam is positioned in the hollow rectangle of the silicon substrate frame; the other end of the quartz tuning fork beam is fixed on the silicon substrate frame through organic adhesive; the silicon substrate frame is sputtered with a metal electrode; and the metal electrode and the electrode of the quartz tuning fork beam are connected by a gold wire. When a force function is in the presence in a probe sensitivity direction, force amplified by the second-order enlargement beam acts on the quartz tuning fork beam, and the quartz tuning fork beam causes that resonant frequency changes under the function of axial force. The vibrated quartz tuning fork beam is connected into a detection circuit to detect frequency change so as to realize force measurement. Through a way of combining a silicon micro-technology and a quartz processing technology, the force sensor has the advantages of simple structure, frequency output, small volume and high accuracy.

Description

Technical field [0001] The invention belongs to the field of micromechanical electronics (MEMS), and specifically relates to a probe type high-precision force sensor based on a quartz resonator. Background technique [0002] The sensitive device of the quartz resonant force sensor is a quartz resonator, which has high frequency stability. When the resonator is deformed by force, its natural frequency will change accordingly, and the frequency increment has a linear relationship with the stress received by the resonator. Therefore, the force received can be calculated by measuring the frequency change of the resonant circuit; The sensor uses frequency as the output and belongs to a digital sensor. Because the quartz crystal is a linear elastic material close to ideal, there is no hysteresis, and it has outstanding advantages such as excellent stability, so that the sensor can obtain good performance. , It has the characteristics of good stability, good linearity and good repeatab...

AI Technical Summary

Problems solved by technology

Among them, the silicon resonant pressure sensor with electrostatic excitation capacitance pickup developed by Greenwood et al. has an accuracy better than 1 / 10000, but due to the electrostatic excitation method, it is difficult to process; someone has developed a surface processing technology The electromagnetically excited resonant pressure sensor is made of two resonant beams on the surface of the pressure film for differential detection, and its accuracy can reach 1 / 10000, but the processing technology is very complicated due to the surface processing technology

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