Patent ID: 6793843
Filing Date: 2004-09-21
Classification: C04B,H01L

Abstract:
A piezoelectric ceramic comprising:a rhombohedral perovskite structure compound; a tetragonal perovskite structure compound; and an orthorhombic perovskite structure compound, wherein the composition ratio of the rhombohedral perovskite structure compound, the tetragoonal perovskite structure compound and the orthorhombic perovskite structure compound and the composition ratio of an element at an A-site to an element at a B-site in each of these compounds have a relation of 0.9&lE;ax+by+cz<1.0, and wherein a, b and c represent the composition ratio of a rhombohedral perovskite structure compound, a tetragonal perovskite structure compound and an orthorhombic perovskite structure compound in molar ratio, respectively, and x, y and z each represent the composition ratio of an element at the A-site to an element at the B-site in molar ratio in the rhombohedral perovskite structure compound, the tetragonal perovskite structure compound and the orthorhombic perovskite structure compound, respectively.