TETRAGONAL MgSiO3 CRYSTAL, ITS PRODUCING METHOD AND PIEZOELECTRIC ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a new tetragonal MgSiO₃ crystal which is free from lead, exhibits excellent piezoelectric characteristics and has especially biocompatibility; a method for producing the same; and a piezoelectric element which is free from lead and has biocompatibility.;SOLUTION: A thin film of the tetragonal MgSiO₃ crystal is formed on a crystalline substrate (a silicon single crystal substrate or a substrate obtained by forming a buffer layer on the substrate) by the epitaxial growth of Mg and Si in an oxygen atmosphere using a PVD method (helicon wave reactive sputtering method or the like). As the buffer layer, a layer having a lattice constant in a specified range is required for obtaining the tetragonal MgSiO₃ crystal. Above all things, a buffer layer obtained by forming a metal or metal oxide thin film (iridium thin film or iridium oxide thin film) is preferable. The thin film of the tetragonal MgSiO₃ crystal can be used as a piezoelectric element for a piezoelectric actuator of an electronic device, especially a piezoelectric actuator for a medical instrument.;COPYRIGHT: (C)2006,JPO&NCIPI