The effects of material selection for backing and wear protection/quarter-wave matching of piezoelectric polymer ultrasound transducers

Selection of the proper backing material for a piezoelectric polymer ultrasonic transducer demands careful design consideration. Many ultrasonic transducers also require a front layer to protect the otherwise exposed electroding from the environment. By carefully choosing the right front layer material, one can also improve acoustic performance with the use of a quarter-wave matching layer. However, there are few practical materials which can be effectively used for quarter-wave matching polymer transducers. This paper describes the practical selection of materials for the design of the backing substrate and front wear/matching layers for piezoelectric polymer ultrasound transducers.