A 70 MPa silicon resonant pressure microsensor with resonators supported by micro beams based on volume compressed...

Area of Science:

• * Materials Science and Engineering
• * Mechanical Engineering
• * Sensor Technology

Background:

• * Growing demand for high-accuracy, high-resolution, and fast-response pressure microsensors in ocean science and the petroleum industry.
• * Limitations of existing microsensors in meeting these stringent requirements under high-pressure conditions.

Purpose of the Study:

• * To develop a silicon resonant high-pressure microsensor utilizing volume compressed sensing with dual resonators.
• * To enhance sensor performance through innovative microbeam support structures and achieve temperature self-compensation.
• * To provide a robust solution for complex hydraulic measurements in challenging environments.

Main Methods:

• * Fabrication of a silicon resonant microsensor featuring dual resonators supported by microbeams.
• * Theoretical modeling of microbeam behavior under pressure to optimize geometric parameters for differential pressure sensitivities.
• * Wafer vacuum packaging using eutectic bonding and sealing with a corrugated diaphragm for hydraulic measurements.

Main Results:

• * Quantified pressure sensitivities of 0.003 kHz/MPa for Resonator I and -0.118 kHz/MPa for Resonator II at 20°C, aligning with theoretical predictions.
• * Achieved accuracy better than 0.01% FS with temperature self-compensation across a pressure range of 0.1–70 MPa and temperatures from -10°C to 50°C.
• * Demonstrated a response time better than 10 ms and a resolution of 100 Pa.

Conclusions:

• * The developed microbeam structure effectively enhances resonant high-pressure microsensors combined with volume compressed sensing.
• * Established a quantitative relationship between microbeam geometric parameters and sensor sensitivity.
• * Successfully demonstrated the feasibility of high-accuracy, high-resolution pressure measurements over a wide range, meeting critical industry demands.