Micro force sensor integrated with sensitive membrane and force transmission guiding rod and processing method thereof

Abstract

The invention relates to a micro force sensor integrated with a sensitive membrane and a force transmission guiding rod. The sensor comprises a sensitive membrane and a force transmission guiding rodthat are fixedly connected. The sensitive membrane includes a substrate, a central plate disposed at the central position of the substrate, a cantilever beam connected between the substrate and the central plate, and a piezoresistor arranged on the cantilever beam. A contact hole matching the piezoresistor is formed in the substrate; and a metal lead and the piezoresistor form ohmic contact in thecontact hole and form a Wheatstone bridge. The central plate is connected to the force transmission guiding rod in an integrated manner. Compared with the prior art, the micro force sensor has advantages of simple preparation, low cost, small measurement error, great convenience in installation and the like.

Description

technical field [0001] The invention relates to the technical field of sensors, in particular to a micro force sensor integrating a sensitive film and a force transmission guide rod and a processing method thereof. Background technique [0002] With the advent of the new technology revolution, the world has entered the information age, and sensors, as the main way and means to obtain information in the fields of nature and production, have played a great role. Some weaknesses in our country's sensor testing process are inevitably revealed, such as certain improvements in the testing of pressure-sensitive sensors. [0003] For this reason, the present invention designs a micro force sensor in which a sensitive film and a force transmission guide rod are integrally prepared. The micro force sensor is a device made by spreading resistance on the substrate of the semiconductor material according to the piezoresistive effect of the semiconductor material. The basic principle is...

AI Technical Summary

Problems solved by technology

[0004] The traditional method of testing the pressure-sensitive sensor is usually prepared separately from the pressure-sensitive sensor and the force-transmitting rod, and the pressure-sensitive sensor and the force-transmitting rod are connected through an adhesive. It is very difficult, and it is easy to affect the force conduction in the follow-up measurement work of the pressure-sensitive sensor. For the delicate components of the sensor, it is easy to cause measurement errors

Ritsumeikan University Dzung et al. prepared a micro force sensor for measuring robot finger force in 2006 through microfabrication (see "SIX-DEGREE OF FREEDOM MICRO FORCE-MOMENTSENSOR FOR APPLICATION IN GEOPHYSICS" 2002 Proceedings of the IEEEInternational Conference on Micro Electro Mechanical Systems (MEMS) February 2002, pp.312-315), but the installation between the pressure-sensitive sensor and the force transmission rod is cumbersome during the test process and the force transmission is easily affected and causes errors, so it is not suitable for mass production

[0005] Chinese patent CN104729784 A discloses a beam-groove combined stepped island membrane micro-pressure sensor chip and its preparation method. The chip includes a thin film in the middle of the base, four shallow grooves are distributed along the upper edge of the thin film, and four relief beams are arranged on adjacent two shallow Between the ends of the grooves and the base, the upper surface of the embossed beam, the upper surface of the film and the bottom surface of the shallow groove form a beam-groove combined stepped film structure. Four piezoresistor strips are arranged on the four embossed beams. Metal leads The varistor strips are connected to form a semi-open-loop Wheatstone bridge, and the output end of the bridge is connected to the pad; the four bumps are evenly distributed along the lower edge of the film and connected to the substrate; the four mass blocks are spaced from the bumps by distance, the bumps are connected on the film, and the preparation method is to oxidize the SOI silicon wafer at high temperature to make a varistor strip, obtain the ohmic contact area to make metal leads and pads; then make four embossed beams and shallow grooves, and finally connect the back of the substrate with the anti- Overload glass bonding; however, this patented technology is a traditional piezoresistor structure, and the force acts directly on the piezoresistor, which limits the application field of the sensor and reduces the sensitivity of force transmission

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