Title :
Multi-layered ultrasonic transducers employing air-gap structure
Author :
Yoshimoto, Susumu ; Sakamoto, Masamichi ; Hashimoto, Ken-Ya ; Yamaguchi, Masatsune
Author_Institution :
Dept. of Electr. & Electron. Eng., Chiba Univ., Japan
fDate :
5/1/1995 12:00:00 AM
Abstract :
Aiming at developing miniaturized ultrasonic image sensors with high spatial resolution, this paper proposes multi-layered ultrasonic transducers employing air-gap structure. Theoretical analysis suggests that if the device is optimally designed, its performance is little affected by the layer supporting the air-gap structure, and that low-loss, wide-bandwidth transducers having practical mechanical strength could be developed. The transducer consisting of polymer/Pyrex-glass/ZnO/Pyrex-glass layers was fabricated, and a conversion loss of 11.6 dB and -3 dB relative bandwidth of 7.8% were obtained. The transducer was also applied to nondestructive testing, and its basic performance was shown.<>
Keywords :
air gaps; image sensors; mechanical strength; ultrasonic materials testing; ultrasonic transducers; 11.6 dB; ZnO; air-gap structure; conversion loss; mechanical strength; multi-layered ultrasonic transducers; nondestructive testing; polymer/Pyrex-glass/ZnO/Pyrex-glass layers; spatial resolution; ultrasonic image sensors; wide-bandwidth transducers; Air gaps; Electrodes; Ferroelectric materials; Image sensors; Polymers; Substrates; Ultrasonic transducer arrays; Ultrasonic transducers; VHF circuits; Zinc oxide;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
