title: Fabrication of piezoelectric ceramic micro-actuator and its reliability for hard disk drives.
abstract: A new U-type micro-actuator for precisely positioning a magnetic head in high-density hard disk drives was proposed and developed. The micro-actuator is composed of a U-type stainless steel substrate and two piezoelectric ceramic elements. Using a high-d31 piezoelectric coefficient PMN-PZT ceramic plate and adopting reactive ion etching process fabricate the piezoelectric elements. Reliability against temperature was investigated to ensure the practical application to the drive products. The U-type substrate attached to each side via piezoelectric elements also was simulated by the finite-element method and practically measured by a laser Doppler vibrometer in order to testify the driving mechanics of it. The micro-actuator coupled with two piezoelectric elements featured large displacement of 0.875 microm and high-resonance frequency over 22 kHz. The novel piezoelectric micro-actuators then possess a useful compromise performance to displacement, resonance frequency, and generative force. The results reveal that the new design concept provides a valuable alternative for multilayer piezoelectric micro-actuators.
authors.affiliation: State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, PR China. jingy@post.pim.tsinghua.edu.cn
authors.forename: Yang
authors.initials: Y
authors.lastname: Jing
authors.forename: Jianbin
authors.initials: J
authors.lastname: Luo
authors.forename: Wenyan
authors.initials: W
authors.lastname: Yang
authors.forename: Guoxian
authors.initials: G
authors.lastname: Ju