Method for manufacturing integrated piezoresistance SiO2 cantilever by wet etching

Abstract

The invention relates to a method for manufacturing an integrated piezoresistance SiO2 cantilever on a single side of a siliconchip with low cost by wet etching, and belongs to the technical field of silicon micromechanical manufacturing. The method is characterized in that: tetramethyl ammonium hydroxide aqueous solution is used for releasing a SiO2 cantilever structure through anisotropic etching, a Ti-Au-Cr three-layer composite metal is used as a lead wire to form good ohm contact with silicon piezoresistance, and simultaneously the method is compatible with the wet etching and late-stage chemical sensitive modification. The method has the characteristics of low cost of manufacturing process, time conservation, high yield, capability of producing the cantilever in batches and convenient integration with piezoresistance.

Description

technical field [0001] The present invention relates to a method for making a silicon dioxide micro-cantilever beam, more precisely to a method of using tetramethylammonium hydroxide aqueous solution (TMAH) wet etching to release a cantilever beam structure from a single side of a silicon chip at low cost and a three-layer A method of forming a good ohmic contact between a metal composite lead and a silicon piezoresistor. The invention belongs to the technical field of silicon micromachine manufacturing. Background technique [0002] At present, micromachined cantilever beam sensors have been widely used in biochemical detection, pressure sensitivity, and inertial measurement due to their small size, high sensitivity, rapid response, and strong applicability. Among them, the use of stress-sensitive silica micro-cantilever sensors has broad prospects in chemical detection, biological reactions, and microfluidic chips due to their simple structure, high sensitivity, high sign...

AI Technical Summary

Problems solved by technology

However, due to the high cost and long time consumption of the deep reactive ion etching process, it is difficult to carry out mass production

Poor uniformity of xenon difluoride gas etching process leads to low yield

Moreover, during the etching process of xenon difluoride gas, fluorine ions will also corrode the photoresist mask, making it difficult to remove after the etching is completed.

In addition, fluorine ions will also occupy the gold film layer on the surface of the cantilever beam through chemical bonding, resulting in the inability to grow a single-molecule self-assembly layer on the surface of the gold film layer during the subsequent chemical surface sensitive modification of the sensor, so that the sensor cannot work.

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