S. Saitoh et al., A 20 MHZ SINGLE-ELEMENT ULTRASONIC PROBE USING 0.91PB(ZN1 3NB2/3)O-3-0.09PBTIO(3) SINGLE-CRYSTAL/, IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 45(4), 1998, pp. 1071-1076
A 20 MHz single-element ultrasonic probe using 0.91Pb(Zn1/3Nb2/3)O-3-0
.09PbTiO(3) (PZN-PT 91/9) single crystal has been fabricated. The sing
le crystal of PZN-PT 91/9 orientated to the (001) plane has longitudin
al coupling factor of k(33) > 90%, which is much larger than the k(33)
= 70 to 80% of conventional Pb(Zr1-xTix)O-3 (PZT) based ceramics. A s
ingle crystal of PZN-PT 91/9 without inclusion or crack has been grown
with dimensions of about 25 x 15 x 5 mm by the self-flux method. Beca
use mechanical strength in the fabrication of disk transducers orienta
ted to the (001) plane was sufficiently strong, under the same conditi
ons as are applied to conventional PZT ceramics, a piston single-eleme
nt probe with a diameter of 2.0 mm and a frequency of 20 MHz was succe
ssfully fabricated. The bandwidth of the PZN-PT 91/9 probe was 13-26 M
Hz, which was 4 MHz broader than that of the conventional PZT probe.