Advances in silicon carbide pressure sensors for high-temperature extreme environment sensing

In fields such as aerospace, geothermal energy, Venus exploration, and nuclear power safety, large-scale equipment often operates under extreme conditions characterized by high temperatures, radiation, corrosive gases, and vibration. Pressure monitoring at critical locations is essential for equipment condition monitoring, fault diagnosis, and improving operational efficiency. Microelectromechanical system (MEMS) sensors, with advantages including small size, high integration, and batch manufacturability, represent the mainstream application of industrial intelligent sensors. However, traditional silicon (Si)-based pressure sensors are limited by material properties, and the performance degrades due to PN junction leakage current and mechanical deformation. While silicon-on-insulator (SOI) sensors still face challenges, such as high-temperature plastic deformation and insufficient reliability. Silicon carbide (SiC), as a third-generation wide-bandgap semiconductor, offers significant advantages, including a high bandgap, radiation resistance, and corrosion resistance. These properties make SiC a promising substrate material for overcoming the bottleneck in high-temperature pressure sensing. Nevertheless, the current study is confined to a laboratory prototype. Performance under extreme conditions needs to be enhanced, especially the allowable operating temperature range, sensitivity, and stability. This paper reviews the evolution of various types of high-temperature pressure sensors systematically. Key technologies for SiC pressure sensors, including structural design, sensor chip fabrication, high-temperature ohmic contacts, packaging and reliability validation, are discussed. The latest research progress is summarized, and existing technical problems are analyzed. Finally, the challenges for SiC high-temperature pressure sensor research are discussed, and perspectives on future development trends are presented. This review aims to provide theoretical support and innovative directions for SiC pressure sensing technologies in extreme environments.