pp. 199-210
S&M558 Research Paper of Special Issue Published: 2004 Piezoelectric Composites of Fine PZT Rods Realized by LIGA Process [PDF] Yoshihiro Hirata, Kazuo Nakamae, Toshiyuki Numazawa and Hiroshi Takada (Received March 26, 2004; Accepted July 23, 2004) Keywords: piezoelectric composites, LIGA process, ultrasonic diagnosis
A ceramic microfabrication process has been developed for a 1–3 piezoelectric composite. This composite material was predicted to be suitable for high-frequency and wideband ultrasonic transducers used in diagnostic medicine and nondestructive testing. However, no process was available to fabricate micro- and high-aspect-ratio lead zirconate titanate (PZT) columnar arrays; therefore, a piezoelectric composite for high-frequency ultrasonic transducers was not realized. We developed a process which employs synchrotron radiation (SR) lithography, electroforming, and micromolding, generally called the “LIGA process.” This process produced an array of PZT columns whose cross-sectional area is 25 µm2 and 250 µm high. As expected from theory, the mechanical quality factor (Qm) is lower and the electromechanical coupling coefficient in the thick mode (kt) is higher than conventional materials. Using the composite developed in an ultrasonic endoscope, the ultrasonic pulse-width was improved from 240 ns to 180 ns, and the bandwidth was expanded from 60% to 150%.
Corresponding author: Yoshihiro HirataCite this article Yoshihiro Hirata, Kazuo Nakamae, Toshiyuki Numazawa and Hiroshi Takada, Piezoelectric Composites of Fine PZT Rods Realized by LIGA Process, Sens. Mater., Vol. 16, No. 4, 2004, p. 199-210. |