Application of single crystal relaxor ferroelectric materials to medical imaging arrays

Single crystal relaxor ferroelectrics have been shown to possess extremely high electromechanical coupling coefficients, in some materials approaching 95% in length extensional mode. This high coupling allows the design of electroacoustic transducers with better sensitivity or bandwidth than can be achieved with conventional piezoceramic materials. These improved properties come at the expense of lower depoling temperatures, increased material fragility, poorer property uniformity, and increased cost. These issues preclude the adoption of single crystals as a direct drop‐in replacement for conventional piezoceramics. Most issues can be addressed through refined crystal growth and transducer design or processing methods. This paper reviews the application of single crystals to transducers for medical imaging, including: characterization of material properties including the complete matrix of elastic, dielectric, and piezoelectric coefficients; design of high bandwidth transducers; modeling of transducer op...