Patent attributes
A piezoelectric device is formed by simultaneously firing a piezoelectric ceramic mainly composed of a perovskite complex oxide represented by general formula ABO3 and electrodes mainly composed of copper. The piezoelectric ceramic is represented by Pbα−aMea[(MII1/3MV(2+b)/3)zTixZr1−x−z]O3 (wherein Me represe element, MII is an acceptor element which is a divalent metal element, and MV is a donor element which is a pentavalent metal element), and satisfies equations 0.05≦z≦0.40, 0<bz/3≦0.035, 0.345≦x≦0.480, 0.965≦α≦1.020, and 0≦a≦0.05. In other words, the B sites contain excessive donors, and thus a piezoelectric device having good piezoelectric characteristics can be obtained even in the cases where a base metal material mainly composed of inexpensive copper is used as the internal electrode material.
