A Resonant High-Pressure Microsensor Based on the Vertical Dual Resonators With Oil-Filled Isolated Structure

This letter developed a resonant high-pressure microsensor with a measurement range of 30 MPa based on a vertical distribution of dual resonators and an oil-filled structure. More specifically, dual resonators were vertically deployed in an H-cavity and were subjected to compressive and tensile stresses under applied pressures while the sensing unit was surrounded by silicon oil and sealed by a corrugated diaphragm structure and a base house for hydraulic measurements. Microfabrication was conducted to fabricate the microsensor and the pressure sensitivities were quantified as 0.135 kHz/MPa (~2103 ppm/MPa) of Resonator I, −0.085 kHz/MPa (~-1358 ppm/MPa) of Resonator II, and 0.219 kHz/MPa (~3461 ppm/MPa) of the differential output of the dual resonators under 20°C, producing fitting and measurement accuracies of 0.01%FS under a pressure range of 0.11-30 MPa and a temperature range of −10-60°C. This study provided a new perspective in the field of high-pressure measurements in harsh environments with high accuracies and sensitivities.