Title :
A novel method to fabricate full-kerfed highfrequency (>100 MHz) ultrasonic array transducers
Author :
Zhang, J.Y. ; Ji, X.M. ; Zhou, J. ; Huang, Y.P. ; Xu, W.J. ; Carlier, J. ; Gao, J.M. ; Nongaillard, B.
Author_Institution :
Dept. of Microelectron., Fudan Univ., Shanghai, China
Abstract :
High-frequency ultrasonic transducer arrays are essential for efficient imaging in clinical analysis and nondestructive evaluation (NDE). However, the fabrication of piezoelectric transducers is really a great challenge due to the small features in piezoelectric films. This paper describes a novel technique to fabricate thick-film ZnO ultrasonic array transducers. Piezoelectric elements are formed by sputtering thick-film ZnO onto etched features of a silicon substrate so that the difficult etching process for ZnO films is avoided by etching silicon. This process is simple and efficient. A 13-μm-pitch ZnO sandwich array is achieved with a thickness of 8 μm for 300 MHz. Finite element method is employed to calculate its electrical properties, including electrical impedance and crosstalk. The array is characterized by a network analyzer. The measured results are in good agreement with the theoretical predictions.
Keywords :
biomedical ultrasonics; finite element analysis; piezoelectric thin films; piezoelectric transducers; sputter etching; ultrasonic transducer arrays; zinc compounds; NDE; ZnO; clinical analysis imaging; crosstalk; electrical impedance; electrical properties; etched features; fabrication; finite element method; full-kerfed high-frequency ultrasonic array transducers; nondestructive evaluation; piezoelectric elements; piezoelectric films; piezoelectric transducers; silicon substrate; sputtering; thick-film ZnO ultrasonic array transducers; Acoustics; Arrays; Films; Finite element methods; Silicon; Zinc oxide;
Conference_Titel :
Ultrasonics Symposium (IUS), 2011 IEEE International
Conference_Location :
Orlando, FL
Print_ISBN :
978-1-4577-1253-1
DOI :
10.1109/ULTSYM.2011.0434