Wide-range high-precision double film-integrated capacitive pressure sensor and manufacturing method

Abstract

The invention relates to the technical field of pressure sensors and particularly relates to a wide-range high-precision double film-integrated capacitive pressure sensor and a manufacturing method. The wide-range high-precision double film-integrated capacitive pressure sensor comprises a glass substrate; a first shallow groove and a second shallow groove are arranged in the glass substrate; the first shallow groove and the second shallow groove are communicated through a thin groove; the center position of the second shallow groove is provided with a shallow groove through hole; the shallow groove through hole extends to the bottom surface of the glass substrate from the bottom surface of the second shallow groove; the first shallow groove is provided with a capacitor C1 capable of measuring a low pressure difference; the second shallow groove is provided with a capacitor C2 capable of measuring a high pressure difference; the capacitor C1 capable of measuring the low pressure difference comprises a bottom electrode plate and a thin pressure sensitive film; the capacitor C2 capable of measuring the high pressure difference comprises a thick pressure sensitive film and a top electrode plate; the shallow groove through hole and the capacitor C1 capable of measuring the low pressure difference are arranged correspondingly; and the shallow groove through hole and the capacitor C2 capable of measuring the high pressure difference are arranged correspondingly. Through the capacitor C1 capable of measuring the low pressure difference and the capacitor C2 capable of measuring the high pressure difference, high-precision pressure measurement in a low pressure section and a high pressure section can be realized respectively.

Description

technical field [0001] The invention relates to the technical field of pressure sensors, in particular to a wide-range, high-precision integrated double-membrane capacitive pressure sensor and its manufacturing method, especially the thin and thick two-layer pressure-sensitive film distributed in the horizontal direction, which is formed at the same time in the low-pressure section and the high-pressure section. A pressure sensor structure with high measurement sensitivity. Background technique [0002] Pressure sensors are widely used in the fields of medical treatment, sanitation, industrial process control, automotive electronics, and consumer electronics. There are many types of pressure sensors on the market, which can be roughly divided into several categories according to different measurement principles: strain gauge, silicon piezoresistive, piezoelectric, capacitive, and resonant. Among them, the capacitive pressure sensor is an ideal upgrade product of the piezore...

AI Technical Summary

Problems solved by technology

Due to the characteristics of its own structure, the range and sensitivity are mutually restricted. In order to obtain higher sensitivity, the range must be sacrificed, which limits the application range of this type of sensor.

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