TY - JOUR
T1 - Characterizing Ultra-Thin Matching Layers of High-Frequency Ultrasonic Transducer Based on Impedance Matching Principle
AU - Wang, Haifeng
AU - Cao, Wenwu
N1 - Funding Information:
Manuscript received April 8, 2003; accepted October 4, 2003. This research was sponsored by the NIH Grant for the Ultrasonic Transducer Engineering Resource (Grant number P41-RR11795-06).
PY - 2004/2
Y1 - 2004/2
N2 - The quarter-wavelength (λ/4) acoustic matching layer is a vital component in medical ultrasonic transducers, which can compensate for the large acoustic impedance mismatch between the piezoelectric material and the human body. At high frequencies (∼100 MHz), the λ/4 matching layers become extremely thin, and the characterization of their properties becomes very challenging. We report a method to measure the phase velocity and attenuation of ultra-thin layers using the λ/4 matching principle, in which the acoustic impedance of the thin layer is between the substrate and water. The method has been successfully used to characterize epoxy films on glass substrate. The experimental results show good agreement in the phase-velocity measurement between our proposed method and the conventional ultrasonic spectroscopy method, but the attenuation measurement is sensitive to the properties of the substrate and water medium as well as the alignment of the sample.
AB - The quarter-wavelength (λ/4) acoustic matching layer is a vital component in medical ultrasonic transducers, which can compensate for the large acoustic impedance mismatch between the piezoelectric material and the human body. At high frequencies (∼100 MHz), the λ/4 matching layers become extremely thin, and the characterization of their properties becomes very challenging. We report a method to measure the phase velocity and attenuation of ultra-thin layers using the λ/4 matching principle, in which the acoustic impedance of the thin layer is between the substrate and water. The method has been successfully used to characterize epoxy films on glass substrate. The experimental results show good agreement in the phase-velocity measurement between our proposed method and the conventional ultrasonic spectroscopy method, but the attenuation measurement is sensitive to the properties of the substrate and water medium as well as the alignment of the sample.
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U2 - 10.1109/TUFFC.2004.1295396
DO - 10.1109/TUFFC.2004.1295396
M3 - Article
C2 - 15055811
AN - SCOPUS:1642618221
SN - 0885-3010
VL - 51
SP - 211
EP - 215
JO - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
IS - 2
ER -