Capacitive MEMS acceleration sensor

Abstract

A capacitive MEMS acceleration sensor comprising an MEMS acceleration chip (1), a signal processing chip (2) and a substrate (3). The MEMS acceleration chip (1) comprises a cover body (4), a micromechanical system (5) and a circuit substrate (6), the micromechanical system (5) is composed of an X-axis acceleration induction area (7), a Y-axis acceleration induction area (8) and a Z-axis acceleration induction area (9); the Y-axis acceleration induction area (8) comprises a Y-direction 'H'-shaped moving sheet (81) with two through holes, two Y-direction moving electrodes (82) and two Y-direction fixed electrodes (83); the Z-axis acceleration induction area (9) comprises a mass block (24) and a supporting shaft (25) for supporting the center of the mass block (24); the lower surface of the circuit substrate (6) is bonded with a partial area on the upper surface of the signal processing chip (2) through a first insulation adhesive layer (12); the upper surface of the circuit substrate (6) is provided with a plurality of chip welding points (14), the upper surface of the substrate (3) is provided with a plurality of substrate welding points (15) which are distributed in the edge areas on the two sides of the substrate (3), and the upper surface of the signal processing chip (2) is provided with signal input welding points (16) and signal output welding points (17) respectively. The capacitive MEMS acceleration sensor improves the reliability of a device and effectively reduces stress damage to the chips by an external force.

Description

technical field [0001] The invention relates to the technical field of acceleration sensors, in particular to a capacitive MEMS acceleration sensor. Background technique [0002] MEMS acceleration sensors have attracted much attention due to their small size, light weight, low cost, and high reliability, especially in the fields of aerospace and weapon science, which have high requirements for the volume, quality, and reliability of devices. Application prospects. The research on acceleration sensors has developed rapidly in recent years, and high-range acceleration sensors with various performances and ranges have been reported one after another. However, the accelerometer has high requirements for high overload resistance and natural frequency. Usually, the high overload resistance is required to withstand hundreds of thousands of range impact loads, and the natural frequency is required to be as high as tens of kHz, or even hundreds of kHz. Therefore, in applications, M...

AI Technical Summary

Problems solved by technology

Practice has shown that the existing sensor packaging technology generally has the problems of poor resistance to high overload, low natural frequency, and poor packaging reliability. , there are often problems such as shell cracking, cover plate depression, chip falling off from the shell substrate, lead wire breakage, etc.

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