MEMS gyroscope and preparation and packaging method thereof

Abstract

The invention discloses an MEMS gyroscope and a preparation and packaging method thereof. The MEMES gyroscope is of a tuning fork type gyroscope structure and comprises an outer frame, a mass block, an anchor point, a driving unit, a detection unit, a first-stage elastic connecting beam, a second-stage elastic connecting beam and a coupling elastic connecting beam. The driving mode is in-plane reverse oscillation motion of the two mass blocks relative to the outer frame, and the sensing mode is in-plane torsional pendulum motion of the whole structure. Detected Coriolis force signals are output in a differential mode through the induction electrodes located at the four corners of the outer frame. Through the driving mass block of the MEMS gyroscope, full coupling is achieved, meanwhile, fewer anchor point structures are provided, errors caused by machining errors and packaging stress can be effectively restrained, and therefore the precision and performance of the MEMS gyroscope are improved. According to the preparation and packaging method provided by the invention, vacuum packaging of the device is realized by using a wafer level vacuum bonding method, the difficulty of device design, preparation and electrical wiring is reduced, and the method is simple and efficient.

Description

technical field [0001] The invention relates to the field of MEMS gyroscope sensor design and processing, in particular to a MEMS gyroscope and a preparation and packaging method thereof. Background technique [0002] The gyroscope is a sensing device that measures the rotation angle or angular displacement of an object. It is used to realize the measurement and control of the attitude and trajectory of the moving carrier. It is the basic core device of the inertial system. Compared with traditional mechanical and optical gyroscopes, micro-electro-mechanical system (MEMS) gyroscopes have the advantages of low cost, small size, low power consumption, and can be integrated with circuits. They are widely used in consumer electronics and medical electronics. , automotive electronics, aerospace and military and other fields. The most widely used commercial MEMS gyroscope is the tuning fork gyroscope. Its principle is the Coriolis effect. When the platform rotates, the suspended ...

AI Technical Summary

Problems solved by technology

At present, commercial gyroscopes have the following disadvantages: 1. The coupling between sub-gyroscopes is generally connected by spring beam structure, which is a weak coupling structure

When there are processing defects and errors, the resonant frequencies between sub-gyroscopes cannot be perfectly matched, and different sub-gyroscopes respond differently to external input angular velocity signals, resulting in readout signal errors

2. At present, the number of anchor points in commercial gyroscope structures is generally greater than four. More anchor point structures make gyroscope devices vulnerable to packaging stress, which leads to a decline in the performance of MEMS gyroscopes.

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