Optimization of High-Temperature-Resistant Lead Structure for MEMS High-Temperature Pressure Sensors
Silicon-on-insulator high-temperature pressure sensors can operate at temperatures above 125 ℃ due to their unique properties.Generally,the resistance forming the Wheatstone bridge is located solely in the pressure-sensitive region to enhance its sensitivity.However,during its operation,a certain height difference exists between the resistance of the heavily doped region of the pressure sensor device and its connection with the metal lead.The thermal stress in this area increases under high-temperature conditions during pressurization and electrification.Met-al leads cannot meet the high-temperature requirements and may break or fail due to overheating.Therefore,this study investigated a silicon lead technology that had the same layer height as a varistor.A metal lead was laid flat on this silicon lead,and the end was annealed to form a robust ohmic contact.Experimental testing demonstrated that this method could ensure the normal operation of the pressure sensor in a high-temperature environment of 300 ℃.The metal lead was well connected to the resistance zone.The stress in the sensitive area of the sensor was reduced by nearly 50%,and the optimized sensor sensitivity met the design requirements.
silicon-on-insulator(SOI)high-temperature pressure sensorsdevice area resistanceheight differ-encesilicon lead
NETL
NSTL
万方数据
