Single crystal SiC capacitive pressure sensor at 400° C

摘要

Single crystal 3C-SiC capacitive pressure sensors are proposed for high-temperature sensing applications. The prototype device consists of an edge-clamped circular SiC diaphragm with a radius of 400 μm and a thickness of 0.5 μm suspended over a 2 μm sealed cavity on a silicon substrate. The fabricated sensor demonstrates a high-temperature sensing capability up to 400° C, limited by the test setup. At 400° C, the device achieves a linear characteristic response between 1100 torr and 1760 torr with a sensitivity of 7.7 ff/torr, a linearity of 2.1%, a hysterisis of 3.7%, and a sensing resolution of 9.1 torr (12 mbar).