PIEZOELECTRIC MATERIAL, SUBSTRATE FOR PIEZOELECTRIC DEVICE, AND SURFACE ACOUSTIC WAVE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a single crystal piezoelectric material having a large electromechanical coupling coefficient and a delay time temperature coefficient close to null, a substrate for a piezoelectric device and a surface acoustic wave device using the same. SOLUTION: The piezoelectric material is a single crystal expressed by the compositional formula: NdCa4O(BO3)3and has an absolute value of the delay time temperature coefficient of≤30 ppm/°C. The substrate 1 for the piezoelectric device is manufactured by cutting the piezoelectric material in a predetermined cutting orientation and polishing the cut surface. Further, the surface acoustic wave device is manufactured by providing comb-shaped electrodes 2 for exciting the surface acoustic waves to the substrate for the piezoelectric device. COPYRIGHT: (C)2003,JPO