Abstract: In order to meet the urgent needs of in-situ pressure detections at high temperatures, a fiber Fabry-Perot SiC high-temperature pressure sensor was fabricated based on the excellent high temperature resistance of SiC materials. A SiC sensor diaphragm with surface roughness Ra about 11.9 nm was fabricated via an ultrasonic vibration mill-grinding(UVMG) method. A direct bonding using SiC wafer hydrofluoric acid was used to realize the high strength air tightness bonding between SiC sensing diaphragm and SiC substrate. The prepared SiC high temperature resistant pressure sensor prototype was tested in high temperature conditions after a high temperature pressure test system was built. Results demonstrate the sensing capabilities for pressures from 0 to 4 MPa at 600 ℃. The pressure sensor illustrates a good linearity(R2>0.99). The pressure sensitivity is measured to be as 104.42 nm/MPa at 600 ℃. 

Key words: pressure sensor, silicon carbide(SiC), Fabry-Perot interferometer, ultrasonic machining, direct bonding

摘要： 针对高温环境下压力参数的原位测试需求，基于碳化硅（SiC）材料优异的耐高温特性，研制了一种光纤法珀式全SiC结构耐高温压力传感器。采用超声振动铣磨的加工方法制备了表面粗糙度Ra约11.9 nm的SiC传感膜片。利用SiC晶片氢氟酸辅助直接键合技术，实现SiC传感膜片与SiC基板的高强度气密性键合。搭建了高温压力测试系统，对制备的SiC耐高温压力传感器样机进行了高温环境下的性能测试。结果表明，该传感器能够实现600 ℃高温环境下 0~4 MPa范围内的压力测量；600 ℃下传感器的压力灵敏度达到104.42 nm/MPa，具有较高的线性度，R2＞0.99。

关键词: 压力传感器, 碳化硅, 法珀干涉, 超声加工, 直接键合