Silicon substrate quartz acceleration sensor with temperature isolation structure

Abstract

A silicon substrate quartz acceleration sensor with a temperature isolation structure comprises a silicon substrate and a double end fixed quartz tuning fork, wherein a mass block on the silicon substrate is connected with the silicon substrate through two flexible beams, a groove is etched in the portion, on the same side of the flexible beams, of the surface of the silicon substrate, the two ends of the groove are respectively connected with a cavity, on the side of the flexible beams, of the mass block and a cavity below the temperature isolation structure, the temperature isolation structure is composed of a fixing seat and a supporting beam, a supporting seat at one end of the double end fixed quartz tuning fork is fixed on the fixing seat of the temperature isolation structure, a supporting seat at the other end of the double end fixed quartz tuning fork is fixed on the mass block, two fork teeth of the double end fixed quartz tuning fork are connected with the supporting seats through fixing ends, and an electrode is covered on the periphery of the fork teeth. When acceleration has an effect on the sensor, the mass block supported by the flexible beams generates displacement to pull or press the double end fixed quartz tuning fork to change vibration frequency of the double end fixed quartz tuning fork and achieve the measurement of the acceleration by the quartz. The temperature isolation structure of the silicon substrate quartz acceleration sensor can reduce the effect of low temperature on the accuracy of the sensor.

Description

technical field [0001] The invention belongs to the technical field of micro-mechanical electronics, and in particular relates to a quartz acceleration sensor with a temperature isolation structure. Background technique [0002] At present, the acceleration sensor with double-ended fixed quartz tuning fork as the sensing unit has been widely used gradually. This type of sensor has the advantages of frequency output, high signal-to-noise ratio, easy excitation and measurement, etc., and can be applied in high-precision digital navigation systems. The principle of this type of acceleration sensor is to paste the double-ended fixed quartz tuning fork on the metal base processed by traditional technology. The base has a mass block supported by a flexible beam. When the acceleration is applied to the sensor, the mass block is subjected to inertia The action produces displacement, thereby pulling or pressing the double-ended fixed quartz tuning fork, changing the vibration freque...

AI Technical Summary

Problems solved by technology

However, the thermal expansion coefficient of silicon crystal and quartz crystal is very different. When the temperature changes, thermal stress will be generated in the double-ended fixed quartz tuning fork, which seriously interferes with the measurement of the acceleration signal.

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