LITHIUM TANTALATE SINGLE CRYSTAL OF STOICHIOMETRIC COMPOSITION FOR SURFACE ACOUSTIC WAVE ELEMENT, METHOD FOR MANUFACTURING THE SAME AND COMPOSITE PIEZOELECTRIC SUBSTRATE FOR SURFACE ACOUSTIC WAVE ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive LiTaO₃ single crystal which can be used for a surface acoustic wave element, and has improved electric mechanical coupling coefficient and heat conductivity.;SOLUTION: A lithium tantalate single crystal of stoichiometric composition for a surface acoustic wave element is obtained by a pulling method, and contains 0 mol% or more and 0.5 mol% or less of at least one element of Fe, Ni and Co, and a coincident molten composition lithium tantalate single crystal having thickness of 7 mm or more is transformed into the stoichiometric composition by a vapor-phase balance method.;COPYRIGHT: (C)2014,JPO&INPIT