Novel piezoresistance type pressure pickup and method for making same

Abstract

This invention is neotype pressure resistance pressure sensor, including inward-leg wire, package outer, outward-leg wire, pin hole, substrate and the piezoresistor, installing the close structure piezoresistor and the banding piezoresistor,; the four piezoresistors make up of the Wheatstone bridge interconnect structure, a-alloy sputtering from the pin hole, installing the electronic glass mass on the surface of close structure outer. The production method is: (1)mixing; (2)surface thermal oxidization; (3)technic-processing of photoetch and plasma corrosion;(4)photoengraving the pin hole; (5)sputtering a-alloy; (6)static electrostatic encapsulating electronic glass; (7)testing and capsulation. The technic-scheme of this invention makes the production-craft more simple, and compatible with the craft of CMOS integrated circuit plate, and have more high harmonic frequency, and can work in the high temperature circumstance and assuring the compatibility of the production performance.

Description

technical field [0001] The invention relates to a pressure sensor and a preparation method thereof, more precisely, to a filmless piezoresistive pressure sensor made of SOI (Silicon-On-Insulator, silicon on an insulating substrate) material and a preparation method thereof. Background technique [0002] Human beings have entered the information age, and the importance of sensors as collection devices for various types of information is self-evident. The rapid development of microelectronics and micromachining technology has greatly promoted the progress of sensor technology and greatly expanded the application range of sensors. As the most important type of Micro Electro Mechanical Systems (MEMS) products, semiconductor pressure sensors are widely used in many fields such as industrial automation, aerospace, oil well logging, and automobile engines. At present, piezoresistive pressure sensors mostly use a silicon cup structure. Under the action of pressure, the stress film ...

AI Technical Summary

Problems solved by technology

[0003] However, the silicon cup structure also has the following problems: (1) due to the light weight of the stress diaphragm, the response speed of the sensor is low, and the resonance frequency is usually only around kilohertz, which limits the application of the sensor; (2) due to the large size of the substrate Due to the non-uniformity of material thickness and the limitation of surface smoothness, it is difficult to achieve the consistency of stress film thickness of different sensors in silicon cups prepared by anisotropic etching process, and the quality of stress film is the key to determining many characteristics of sensors factors, resulting in large performance differences between sensors; (3) deep anisotropic etching process is difficult to be compatible with complementary metal oxide semiconductor (CMOS) integrated circuit planar process

Images