Design and Investigation of a High-Performance Quartz-Based SAW Temperature Sensor

Area of Science:

• Materials Science
• Sensor Technology
• Acoustic Physics

Background:

• Surface Acoustic Wave (SAW) devices are utilized in various sensing applications.
• Quartz substrates offer desirable piezoelectric properties for SAW devices.
• Accurate temperature sensing is crucial for industrial and environmental monitoring.

Purpose of the Study:

• To design and investigate a SAW temperature sensor utilizing a quartz substrate.
• To analyze the impact of structural parameters on SAW device performance.
• To evaluate the sensor's stability, linearity, and repeatability across a temperature range.

Main Methods:

• Utilized the Coupling-of-Modes (COM) model for theoretical analysis.
• Employed the finite element method (FEM) to study transversal modes.
• Fabricated SAW devices with optimized parameters and conducted experimental testing.
• Measured resonant frequencies from 25 °C to 150 °C.

Main Results:

• Optimizing interdigital transducer (IDT) number, reflector count, and spacing improved sensitivity and frequency stability.
• Fabricated sensors demonstrated high performance stability and data reliability (Bode-Q of 7700) across the tested temperature range.
• The sensor exhibited excellent linearity, repeatability, and a significant Temperature Coefficient of Frequency (TCF).

Conclusions:

• The designed quartz SAW temperature sensor shows high performance and stability.
• Optimized structural parameters are key to enhancing sensor capabilities.
• The sensor's TCF indicates strong potential for industrial process control and environmental monitoring.