Single elastic beam type interdigital capacitor accelerometer

Abstract

The invention relates to a single elastic beam type interdigital capacitor accelerometer, which comprises a substrate, an upper anchor point, a lower anchor point, interdigital capacitors, elastic beams, mass blocks, a connecting beam, a left anchor point and a right anchor point, wherein the upper anchor point, the lower anchor point, the interdigital capacitors, the elastic beams, the mass blocks, the connecting beam, the left anchor point and the right anchor point are arranged on the substrate. The accelerometer is characterized in that the interdigital capacitors, the elastic beams, the mass blocks and the connecting beam are of a vertical depositing and stacking structure, the vertical depositing and stacking structure sequentially consists of a first SiO2 (silicon dioxide) coating layer, a first metal aluminum coating layer, a second SiO2 coating layer, a second metal aluminum coating layer, a third SiO2 coating layer, a third metal aluminum coating layer and a passivating layer from bottom to top, the first metal aluminum coating layer and the second metal aluminum coating layer are connected by first tungsten plugs which are arranged in the second SiO2 coating layer, the second metal aluminum coating layer and the third metal aluminum coating layer are connected by second tungsten plugs which are arranged in the third SiO2 coating layer, the vertical depositing and stacking structure is provided with a side wall, the side wall extends from the upper surface of the passivating layer to the upper surface of the substrate, and the base is provided with a suspension structure. The capacitor accelerometer has the advantages that the sensitivity is high, the manufacturability is improved, and the manufacturing cost is low.

Description

technical field [0001] The invention relates to a single elastic beam interdigital capacitance accelerometer, in particular to a single elastic beam interdigital capacitance accelerometer based on CMOS DPTM (Double Poly Triple Metal) mixed signal technology, belonging to the technical field of MEMS device design and manufacture. Background technique [0002] Inertial measurement is a major application aspect of MEMS technology. Integrated inertial sensors have a wide range of applications, including automotive engineering, aviation navigation, consumer electronics and military applications. [0003] Today's mainstream acceleration detection technologies include: capacitance detection technology, piezoresistive detection technology, and tunnel effect current detection technology. Due to the inherent thermal noise of resistance and the characteristics of temperature change of resistance value, accelerometers based on piezoresistive detection technology have low measurement acc...

AI Technical Summary

Problems solved by technology

Due to the inherent thermal noise of resistance and the characteristics of temperature change of resistance value, accelerometers based on piezoresistive detection technology have low measurement accuracy and are mainly used to meet the needs of low-end markets

Tunneling current-sensing technology can be used to realize extremely high-precision accelerometers, but the fabrication of tunneling devices requires a very small gap (10V); so the cost of manufacturing the device is very high. High, and difficult to achieve system integration

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