Silicon capacitor type accelerometer of mechanical modulation

Abstract

The invention discloses a silicon capacitor type accelerometer of mechanical modulation. The accelerometer comprises a substrate, a silicon chip and metal electrodes. The silicon chip comprises a central mass block (100); the central mass block (100) comprises an internal intermediate-frequency movable part (601) and an external low-frequency movable part (602) surrounding the internal intermediate-frequency movable part (601), and the internal intermediate-frequency movable part (601) is connected with the external low-frequency movable part (602) via beams (701). The metal electrodes include mass block electrodes (101), a negative feedback electrode (202), a positive feedback electrode (201), positive driving electrodes (501), negative driving electrodes (502), positive driving detection electrodes (401), negative driving detection electrodes (402), a positive external acceleration detection anode (301) and a negative external acceleration detection anode (302), wherein the mass block electrodes (101) are connected with the central mass block (100) via beams (702).

Description

technical field [0001] The invention relates to the technical field of accelerometers, in particular to a mechanically modulated silicon capacitive accelerometer. Background technique [0002] The silicon capacitive accelerometer belongs to the field of micro-electro-mechanical systems (MEMS, micro-electro-mechanical system). It uses MEMS processing technology to make a silicon wafer (silicon wafer) into a sensitive external apparent acceleration (the so-called apparent acceleration refers to the acceleration in the accelerometer. The sum of the inertial acceleration component and the gravitational acceleration component in the sensitive direction, hereinafter referred to as the acceleration) variable capacitance, supplemented by a follow-up circuit, forms a type of micro accelerometer. Compared with traditional accelerometers, micro accelerometers have many advantages in volume, quality, power consumption, cost, production capacity, and environmental adaptability, but compa...

AI Technical Summary

Problems solved by technology

[0005] However, silicon microresonant accelerometers have technical difficulties such as large temperature drift, low bandwidth, difficulty in closing the loop, difficulty in improving cross-coupling suppression, and high cost of high-precision structures, which restrict the improvement of accuracy and product promotion in a short period of time.

The sandwich silicon capacitive accelerometer also has the problems of high difficulty in process realization and difficult electrical leads, which restricts product promotion and production capacity, and affects the realization of high-precision circuit technology.

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