Electrical extraction of piezoelectric constants

Area of Science:

• Materials Science
• Electrical Engineering
• Solid State Physics

Background:

• Piezoelectric materials are essential components in smart structures, enabling functionality through stress-induced electrical property changes.
• Variations in piezoelectric material dimensions and electrical characteristics under stress directly influence the overall capacitance of the structure.

Purpose of the Study:

• To investigate the application of capacitance-voltage (CV) measurements for extracting piezoelectric coefficients from double piezoelectric thin films.
• To develop and validate a novel algorithm for direct piezoelectric coefficient extraction using CV data.

Main Methods:

• Deposited piezoelectric thin films on a flexible steel sheet using RF sputtering techniques.
• Collected capacitance-voltage measurements using a Gamry analyzer 3000.
• Developed an algorithm to extract piezoelectric coefficients from film thickness, applied voltage, and capacitance ratio.

Main Results:

• The developed algorithm successfully extracts piezoelectric coefficients directly from CV measurements.
• The method was calibrated using a piezoelectric bulk ceramic.
• Validation against literature values confirmed the accuracy of the extracted coefficients.

Conclusions:

• Capacitance-voltage measurements offer a viable and accurate method for characterizing piezoelectric thin films.
• The developed algorithm provides a direct and efficient approach for determining piezoelectric coefficients in smart structures.