Simulation, design, and evaluation of a 64 element 6 MHz ICE transducer using DC poled and AC poled PIN-PMN-PT single crystal

Comparing with binary PMN-PT single crystals, ternary PIN-PMN-PT has higher coercive field strength and Curie temperature, which is more suitable for medical ultrasound imaging applications. The growth technology of 3-inch 23PIN-45PMN-32PT grown in the direction of 〈001〉 has been relatively mature and its stability and consistency have met the needs of medical ultrasound imaging. Comparing with conventional direct current poling (DCP), the relative dielectric constant is increased by 45%, the piezoelectric constant d33 is increased by 58%, and the electromechanical coupling coefficient k33′ also is increased from 0.91 to 0.92 under the optimized alternating current poling (ACP) conditions. Through KLM equivalent circuit model numeric simulation, an acoustic design scheme for a 64-element 10 Fr ICE probe with a center frequency of 6 MHz is determined. The transducers are prepared with piezoelectric plates with two poling methods and their acoustic parameters are tested, which are close to the simulation results; the sensitivity of ACP is 20% higher than that of DCP; and the bandwidth of the two are almost the same. After the evaluation of static phantom, the resolution of the two remains almost the same, and the ACP at penetration depth has obvious advantages. ACP PIN-PMN-PT single crystal plates can be used on high-frequency medical ultrasonic transducers and the performance can be improved a lot from conventional DCP single crystal plates.