SOI-Structured Piezoresistive Pressure Sensor with Integration of Temperature Sensor for Downhole Applications

Area of Science:

• Materials Science
• Electrical Engineering
• Geophysics

Background:

• Micro-Electro-Mechanical Systems (MEMS) sensors are widely used due to their small size, low cost, and light weight.
• MEMS sensors are increasingly applied in oil exploration for downhole pressure and temperature measurements.
• High-precision MEMS sensors are crucial for optimizing oil and gas extraction processes.

Purpose of the Study:

• To design, fabricate, and characterize a novel silicon-on-insulator (SOI) MEMS piezoresistive pressure sensor integrated with a temperature sensor.
• To develop a specialized chamber for emulating downhole conditions in oil exploration wells.
• To evaluate the performance of the MEMS sensor under simulated downhole environments.

Main Methods:

• Physics-based simulations were employed for sensor design.
• Fabrication involved deep reactive ion etching and anodic bonding techniques.
• Characterization included performance evaluation within a custom-designed emulation chamber.

Main Results:

• Successful design and fabrication of the SOI MEMS pressure and temperature sensor.
• The sensor system exhibited a linear response to pressure changes.
• Achieved a sensitivity of 0.0268 mV/V/MPa with a maximum hysteresis of 5.3%.

Conclusions:

• The developed SOI MEMS pressure sensor is suitable for high-precision downhole measurements in oil exploration.
• The integrated design and fabrication process enable robust sensor performance.
• This advancement contributes to improved downhole conductivity and oil extraction efficiency.