Three-dimensional micro-force sensor capable of measuring sub micro Newton force and packaging method of three-dimensional micro-force sensor

Abstract

The invention discloses a three-dimensional micro-force sensor capable of measuring sub micro Newton force and a packaging method of the three-dimensional micro-force sensor. The sensor comprises a contact probe arranged on a sensitive chip; the back face of the sensitive chip is provided with a glass substrate; the sensitive chip uses four L-shaped cantilever beams for supporting a centre supporting film crosswise; twelve piezoresistors are arranged on the cantilever beams; the piezoresistors form three groups of Wheatstone bridges; the contact probe is contacted with an measured object to transfer an external acting force to the centre supporting film of the sensor probe, and change the bending of the cantilever beams of the sensor; the piezoresistors detect the change of stresses and output a voltage signal proportional to a loading force via the Wheatstone bridges so as to complete the test of the external contact force. In the packaging of the sensor, a location cover is used for mounting the probe, so that the verticality of the probe is ensured, and the system error and interference error of the sensor are reduced. The invention has the advantages of small volume, low cost, high resolution ratio, and high stability.

Description

Technical field [0001] The invention relates to the technical field of advanced manufacturing and micro-force measurement, in particular to a three-dimensional micro-force sensor capable of measuring sub-micro Newton force in the form of a piezoresistive high-sensitivity probe based on MEMS technology and a packaging method thereof. technical background [0002] With the continuous development of microelectronics and MEMS technology, and the continuous improvement of semiconductor and bulk silicon processing technology, semiconductor sensors based on MEMS technology are developing in the direction of integration and miniaturization. MEMS micro-force sensor is the basis and key component of micro-force measurement and control. It is widely used in advanced manufacturing, medicine, biomedicine, marine measurement, environmental monitoring and other fields. It is the research focus in the field of micro-force measurement at home and abroad. The current research work mainly includes ...

AI Technical Summary

Problems solved by technology

The processing technology of capacitive MEMS sensor is difficult, the output is nonlinear, and the follow-up circuit is complicated. The piezoelectric sensor is extremely susceptible to environmental humidity and external electromagnetic interference, and the two sensors have the disadvantage of small measurement range, and the measurement displacement is only microns or even nanometers. level, the working environment is severely restricted

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