High frequency PMN–PT single crystal focusing transducer fabricated by a mechanical dimpling technique

High frequency (∼30 MHz and ∼80 MHz) focusing ultrasound transducers were fabricated using a PMN–0.28PT single crystal by a mechanical dimpling technique. The dimpled single crystal was used as an active element for the focusing transducer. Compared with a plane transducer, the focusing transducer fabricated with a dimpled active element exhibits much broader bandwidth and higher sensitivity. Besides, a high quality image can be obtained by the 30 MHz focusing transducer, in which the −6 dB axial and lateral resolution is 27 μm and 139 μm, respectively. These results prove that the dimpling technique is capable to fabricate the high frequency focusing transducers with excellent performance for imaging applications.

► High frequency PMN–PT focused transducers are fabricated by a dimpling technique.
► The focused transducers exhibit better performance than that of the plane one.
► A high quality image can be obtained by the 30 MHz focused transducer.
► The dimpling technique is suitable for high-frequency transducer application.