Single silicon chip integrated chip combining acceleration sensor and pressure sensor and manufacturing method of single silicon chip integrated chip

Abstract

The invention relates to a single silicon chip integrated chip combining an acceleration sensor and a pressure sensor and a manufacturing method of the single silicon chip integrated chip. The single silicon chip integrated chip comprises a single crystal silicon substrate and an acceleration sensor and a pressure sensor both integrated on the single crystal silicon substrate. The acceleration sensor and the pressure sensor are integrated on the same surface of the single crystal silicon substrate through adopting a single silicon chip single-side micro-processing method; a single crystal silicon thin film with a uniform and controllable thickness and an embedded cavity are formed through adopting the side wall root transversal etching technology, and pressure resistance is reasonably distributed on the upper surface of the single crystal silicon thin film to manufacture the pressure sensor; and the acceleration sensor adopts double cantilever beams and a mass block, both the mass block and the cantilever beams are processed and released through the follow-up optional galvanizing and etching to the single crystal silicon thin film, and the quality of the mass block is increased through adopting an electrocoppering method, so as to improve sensitivity. The single silicon chip integrated chip disclosed by the invention has the advantages that the structure is simple; and a non-bonding single silicon chip micro-machinery technology is adopted to realize the manufacturing of a single-side structure of the integrated chip, thereby meeting the requirements on small dimension, low cost and mass production of the sensor chip in TPMS (Tire Pressure Monitor System) application.

Description

technical field [0001] The invention relates to a chip integrating an acceleration sensor and a pressure sensor and a manufacturing method thereof, in particular to an integrated chip of an acceleration sensor and a pressure sensor processed by a single-sided micromachining of a single silicon chip and a manufacturing method thereof, which can be used in TPMS (tire pressure detection system) ), belonging to the technical field of silicon micromechanical sensors. Background technique [0002] In the fields of aerospace, industrial automation control, automotive electronics, navigation, and consumer electronics, parameters such as acceleration and pressure need to be measured simultaneously. For example, in the automobile TPMS (tire pressure monitoring system), the pressure sensor installed in each tire is used to detect the tire pressure in real time, and the information of each tire pressure is fed back to the control panel for real-time display and monitoring to ensure the ...

AI Technical Summary

Problems solved by technology

However, because the detection resistor is processed by polysilicon doping, and the piezoresistive coefficient of polysilicon resistor is much smaller than that of single crystal silicon, the piezoresistive coefficient is about half of that of single crystal silicon, so the sensitivity is low, and it is not suitable For high-sensitivity detection applications

In addition, because the sensor of this structure needs to release the structure by wet etching the sacrificial layer, it is easy to cause thin film adhesion failure, and due to the limitation of thin film deposition, it is not easy to make a large-range pressure sensor

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