电动汽车热泵空调系统用MEMS压力温度传感器

MEMS Pressure Temperature Sensor for Electric Vehicle Heat Pump Air Conditioning System

基于硅压阻效应,利用微电子机械系统(MEMS)技术,研制了一种可用于新能源电动汽车热泵空调系统的激光焊金属密封结构的高可靠MEMS压力温度传感器。采用有限元软件ANSYS对传感器芯片结构进行了应力仿真分析,芯片敏感膜采用线性好、工艺简单、成本低的平膜结构。结合MEMS加工工艺,利用低温硅-硅键合技术、硅通孔(TSV)技术实现了压敏电阻的芯片级介质隔离。设计了传感器的全金属密封结构,搭建了汽车热管理核心热泵空调系统台架,并进行了长期可靠性验证。结果表明,该传感器的基本性能良好,全温区(-40~135℃)传感器压力精度<0.3%FS,可长期应用于新能源电动汽车热管理核心热泵空调系统。

Based on Si piezoresistive effect and with micro-electromechanical system(MEMS)technology,a high reliability MEMS pressure temperature sensor with laser-welded metal seal structure was developed for new energy electric vehicle heat pump air conditioning system.The stress simulation analysis of the sensor chip structure was carried out by using the finite element software ANSYS.And the flat membrane structure with good linearity,simple process and low cost was adopted for the chip sensitive membrane.Combined with MEMS processing technology,low-temperature silicon-silicon bonding technology and through silicon via(TSV)technology were used to achieve chip-level dielectric isolation of varistors.The all-metal sealing structure of the sensor was designed,the core heat pump air conditioning system bench of automotive thermal management was built,and the long-term reliability verification was carried out.The results show that the basic performance of the sensor is good,and the pressure accuracy of the full temperature zone(-40-135℃)is<0.3%FS,which can be applied to the core heat pump air conditioning system of new energy electric vehicle thermal management for a long time.