Fine-Scaled Piezoelectric Ceramic/Polymer 2-2 Composites for High-Frequency Transducer



A novel technique was utilized to fabricate fine-scaled piezoelectric ceramic/polymer 2-2 composites for high-frequency ultrasonic transducers. Lead zirconate titanate (PZT) was used as raw material. Tape-casted acetylene black tapes were used to define kerfs after sintering. A one-directional supporter was utilized to avoid distortion of PZT elements. PZT elements with 20 ± 2 μm width exhibited good consistency in longitudinal direction. A resonant method was utilized to evaluate the piezoelectric and dielectric properties of the composites. A 72-μm-thick composite with an aspect ratio of ~3.6 exhibited a kt of 0.61 with satisfied piezoelectric and dielectric properties. A prototype high-frequency ultrasonic transducer was fabricated and evaluated by an underwater pulse-echo test. The center frequency was found to be 23.75 MHz, with −6 dB bandwidth of 5.5 MHz.