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Updated: May 12, 2026
09:10
The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements
Published on: December 5, 2025
High-precision signal processing algorithm to evaluate SAW properties as a function of temperature.
Ismail Shrena1, David Eisele, Jochen Bardong
1Department of Microsystems Engineering at the University of Freiburg, Freiburg, Germany. shrena@imtek.de
Summary
This study introduces a signal processing algorithm to precisely measure surface acoustic wave (SAW) properties and their temperature dependence. The algorithm accurately determines key acoustic parameters for substrate characterization.
Area of Science:
- Materials Science
- Acoustics
- Signal Processing
Background:
- Surface Acoustic Wave (SAW) devices are crucial in various electronic applications.
- Accurate characterization of SAW properties, especially their temperature dependence, is essential for device performance and reliability.
Purpose of the Study:
- To develop and validate a signal processing algorithm for evaluating SAW properties of substrates as a function of temperature.
- To investigate the temperature dependency of group velocity, phase velocity, propagation loss, and coupling coefficient.
Main Methods:
- The algorithm analyzes transfer functions from short and long delay lines.
- It determines center frequency and delay time difference between delay lines.
- Extracted parameters are used to calculate SAW material acoustic properties.
Main Results:
- The algorithm accurately evaluates SAW properties including group velocity, phase velocity, propagation loss, and coupling coefficient.
- Temperature dependency of these SAW properties is successfully obtained.
- Validation confirms the algorithm's accuracy in calculating delay time difference, center frequency, and group velocity.
Conclusions:
- The developed signal processing algorithm provides an accurate method for characterizing SAW properties and their temperature dependence.
- This method is valuable for the design and optimization of SAW devices operating under varying thermal conditions.
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