Sol-gel fabricated thick piezoelectric ultrasonic transducers for potential applications in industrial material processes

Sol-gel fabricated thick film broadband piezoelectric ultrasonic transducers (UTs) operating at a frequency below 10 MHz are presented. The UTs are formed using thick PZT and LiNbO/sub 3/ films which are ceramic-ceramic composites formed by dispersing PZT and LiNbO/sub 3/ particles in a PZT and LiNbO/sub 3/ sol-gel solution, respectively. Films are directly deposited on stainless steel substrates. Excellent broadband signals have been experimentally obtained with piezoelectric PZT and LiNbO/sub 3/ films with 1 cm diameter and a thickness between 40-50 /spl mu/m.