Beam and groove combined stepped island film micropressure sensor chip and manufacturing method thereof

Abstract

The invention relates to a beam and groove combined stepped island film micropressure sensor chip and a manufacturing method thereof. The chip comprises a thin film in the middle of a substrate, four shallow grooves are formed along the edges of the upper portion of the thin film, four embossment beams are arranged between the ends of the adjacent shallow grooves and connected with the substrate, and the upper surfaces of the embossment beams, the upper surface of the thin film and the bottom faces of the shallow grooves form a beam and groove combined stepped thin film structure; four piezoresistor strips are arranged on the four embossment beams and connected through metal leads into semi-open-loop Wheatstone bridges, and the output ends of the bridges are connected with bonding pads; four bumps are evenly distributed along the edges of the lower portion of the thin film and connected with the substrate; four mass blocks are spaced from the bumps, and the bumps are connected to the thin film. The manufacturing method includes the steps that the piezoresistor strips are made of SOI silicon wafers in an oxidized mode at high temperature, and an Ohmic contact region is obtained to manufacture the metal leads and the bonding pads; then the four embossment beams and the shallow grooves are manufactured, and the back face of the substrate and anti-overload glass are bonded. The beam and groove combined stepped island film micropressure sensor chip has the advantages of being high in sensitivity and linearity and the like.

Description

technical field [0001] The invention relates to the technical field of MEMS piezoresistive micro-pressure sensors, in particular to a beam-groove combined stepped island membrane micro-pressure sensor chip and a preparation method. Background technique [0002] With the development of micro-mechanical electronic system technology, MEMS micro-pressure sensors have been widely used in wind tunnel testing, biomedical and other fields, especially in the aerospace field, there are strict requirements on the volume and weight of the sensor, and the sensor is required to have certain sensitivity and natural frequency. MEMS sensor is undoubtedly a very ideal choice. For example, in the field of aerospace, it is of great significance to monitor the altitude of the aircraft at high altitude, and the pressure has a certain proportional relationship with the altitude, so the change of the altitude of the aircraft can be reflected by the pressure sensor. The atmospheric pressure change...

AI Technical Summary

Problems solved by technology

[0005] my country's current MEMS micro-pressure sensors are still mainly at the kPa level, which cannot meet the requirements of Pa-level micro-pressure measurement in the aerospace field, nor can it adapt to such as the precise measurement technology of deep and high-altitude micro-pressure, and the precise micro-pressure measurement in biomedical equipment. needs in other fields

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