Design And Realization Of Ceramic Piezoresistive Pressure Sensor

Pressure sensor plays an important role in automatic control and detection.It is the basis of pressure signal detection.At present,pressure sensor is the most demanding sensor.Thick film pressure sensor has been widely used in various fields of industry.In China,the gauge factor of resistive paste for thick film pressure sensor lags behind that of foreign pastes of the same type,making domestic full-film pressure sensor with low full-scale output and low strain sensitivity,which leads to a gap with foreign products.Based on this,this paper studies the effect of modifier doping ratio on the gauge factor of thick film resistor paste,adjusts the high temperature sintering process curve according to actual conditions,prints a thick film resistor strain gauge and performs performance test.The working principle,process flow and mechanical properties are studied,a ceramic pressure sensor is fabricated using the modified resistance paste.The main work of this paper is as follows:1.The working principle and process flow of the thick film pressure sensor are studied.With the small deflection theory of the thin plate,the stress and strain distribution of the ceramic elastic diaphragm is studied and analyzed,and the best resistance printed position is determined.Through COMSOL finite element simulation calculation,an integrated sensor base structure is designed.2.The conductive mechanism and piezoresistive effect of thick-film resistor paste are studied.Based on this,the influence of different dosage on the gauge factor of resistance paste is studied,which is doped with 2.5?m glass powder.A thick-film resistor strain gauge is prepared by thick-film technology printing.After testing,a thick-film resistor paste with a gauge factor of 13.82 and a temperature coefficient of 106ppm/°C is obtained.3.The ceramic pressure sensor is fabricated and its static characteristics are tested.The sensitivity of the sensor sample reaches 3.2~3.4m V/V after rectification.The result shows the sensor basically meets the design requirements.For the zero-temperature drift problem,software temperature compensation is performed using piecewise linear interpolation.