SiC Cavity-Based Pressure Sensor With High Dynamic Range

Silicon carbide (SiC) is a promising platform for pressure sensing in harsh environments due to its excellent mechanical and thermal stability. However, its potential for high-resolution sensing remains underexplored. In this work, we present a pressure sensor based on a sealed 4H-SiC cavity and platinum (Pt) piezoresistive strain gauge, designed for room-temperature operation. The Pt resistors form a Wheatstone bridge aligned with the membrane’s simulated stress distribution for optimized sensitivity. The sensor exhibits a linear response over 0 – 200 kPa with 2.6% nonlinearity and 0.47% hysteresis, and reliably detects pressure changes as small as 6 Pa. We employ a two-sample variance analysis, which reveals short-term pressure resolutions of 2.3 Pa at 0.1 s averaging, corresponding to achievable dynamic ranges of 99 dB. These results highlight the potential of SiC–Pt platforms for precise pressure sensing in extreme conditions.