High-frequency PIN–PMN–PT single crystal ultrasonic transducer for imaging applications

A high-frequency (∼60 MHz) ultrasonic transducer with a [001]-oriented 0.27Pb(In1/2Nb1/2)O3–0.45Pb(Mg1/3Nb2/3)O3–0.28PbTiO3 (PIN–PMN–PT) piezoelectric single crystal as an active element has been fabricated and characterized. The poled PIN–PMN–PT single crystal has thickness mode electromechanical coefficient kt of 0.56 and piezoelectric constant d33 of 1550 pC/N. The −6 dB bandwidth of the transducer is 73 % and the insertion loss at its centre frequency is −20 dB. With the study as a function of temperature, the PIN–PMN–PT transducer shows better thermal stability than the binary single crystal transducer. Furthermore, the transducer was evaluated using a 30-μm aluminum wire phantom image, in which the −6 dB axial and lateral resolutions are found to be 26 μm and 127 μm, respectively. Ultrasonic images of fish eyes were obtained with the 60-MHz transducer. It is shown that the high-sensitivity transducer can produce the images with high signal-to-noise ratio and good contrast.