High-temperature SOI pressure sensors on the base of the MEMS micromachining technology

摘要

There is a need of measuring distributed pressure on the compressor inlet of the aircraft engine with high precision within a wide operating temperature range to improve the efficiency of aircraft engine control. The basic solutions and principles of designing high-temperature (to 250°C) microelectromechanical pressure sensors based on a membrane-type SOI heterostructure (SOIMT-MEMS) with a monolithic integral tensoframe (MT) are proposed in accordance with the developed concept which excludes the use of electric p-n junctions in semiconductor microelectromechanical sensors. The SOIMT-MEMS technology relies on the group processes of microelectronics and micromechanics for high-precision microprofiling of three-dimensional micromechanical structure which exclude high-temperature silicon doping processes. According to the design, manufacturing process and experiment results the technology was optimized and a pilot batch of SOIMT-MEMS samples with the regular geometry and without any undercuts of the tensoframe convex angles was manufactured.