Title :
Multi-layer PZT transducer arrays for improved sensitivity [for medical US]
Author :
Goldberg, R.L. ; Smith, Sean W. ; Ladew, Richard A. ; Brent, Jean C.
Author_Institution :
Dept. of Biomed. Eng., Duke Univ., Durham, NC, USA
Abstract :
Two-dimensional arrays are used in medical ultrasound. Poor sensitivity is a serious problem with such 2-D arrays. Sensitivity can be improved by reducing the array element impedance using an N-layer structure of PZT connected electrically in parallel and acoustically in series. The clamped capacitance is multiplied by a factor of N2 and the impedance by 1/N2 compared to a single layer transducer. A 16-layer, 1-MHz prototype transducer is fabricated using thick-film hybrid technology. With a light epoxy backing, the element impedance is 50 Ω at series resonance and the minimum round-trip insertion loss is 41 dB. This is compared to a single-layer control array with an impedance of 3 kΩ per element and an insertion loss of 64 dB per element. These results are consistent with model simulations
Keywords :
acoustic arrays; biomedical equipment; biomedical ultrasonics; ceramics; lead compounds; piezoelectric transducers; thick film devices; ultrasonic transducers; 1 MHz; 41 dB; 50 ohm; MLC; PbZrO3TiO3; clamped capacitance; improved sensitivity; light epoxy backing; minimum round-trip insertion loss; model simulations; multilayer PZT transducer arrays; prototype transducer; thick-film hybrid technology; Acoustic transducers; Biomedical transducers; Capacitance; Impedance; Insertion loss; Prototypes; Resonance; Ultrasonic imaging; Ultrasonic transducer arrays; Ultrasonic transducers;
Conference_Titel :
Ultrasonics Symposium, 1992. Proceedings., IEEE 1992
Conference_Location :
Tucson, AZ
Print_ISBN :
0-7803-0562-0
DOI :
10.1109/ULTSYM.1992.275947
