Forty-channel phased array ultrasonic probe using 0.91Pb(Zn/sub 1/3/Nb/sub 2/3/)O/sub 3/-0.09PbTiO/sub 3/ single crystal

A 0.91Pb(Zn/sub 1/3/Nb/sub 2/3/)O/sub 3/-0.09PbTiO/sub 3/ (PZN-PT) single crystal with high electromechanical coupling factor (k/sub 33/)>90% has been used to fabricate a 40-channel phased array ultrasonic probe with greater sensitivity and broader bandwidth than conventional probes. This probe has a center frequency of 3.5 MHz and an aperture of about 6.0/spl times/7.5 mm. The standard probe fabrication process was modified for PZN-PT. The dispersion of echo signals was within /spl plusmn/20% of the mean value. After recovery poling, the echo amplitude of the PZN-PT single-crystal probe is 8 and 5 dB higher than that of one- and two-matching-layer PZT probes, respectively. Moreover, the fractional bandwidth of the single-matching-layer PZN-PT probe is broader than that of the two-matching-layer PZT probes. The PZN-PT single crystals provide great improvements in the sensitivity and bandwidth of phased array probes.