Piezoelectric composites for micro-ultrasonic transducers realized with deep-etch X-ray lithography

Abstract

PIEZOELECTRIC COMPOSITES FOR MICRO-ULTRASONIC TRANSDUCERS REALIZED WITH DEEP-ETCH X-RAY LITHOGRAPHY Yoshihiro Hirata, Hiroshi Okuyama, Seiji Ogino* Toshiyuki Numzawa and Hiroshi Takaah Harima Research Laboratories, Sumitomo Electric Industries, Ltd. 1431-12 Harima Science Garden City, Kamigori, Hyogo 678-12, Japan Piezoelectric ceramics/polymer composites have been developed for micro-ultrasonic transducers. These composites are made up of micro rods of lead zirconate titanate (PZT) ceramics with high aspect ratio (diameter: 17pm, height: up to 120pm, density: 1,700 rods/"*). PZT rods were fabricated using deep-etch X-ray lithography, PZT slurry casting into a resist structure, plasma etching for resist removal, and sintering. Piezoelectric coefficient d , frequency constant N, and electromechanical coupling coefficient k of the composites were measured, and these composites were proven to have good piezoelectricity.