Patent ID: 7874649
Filing Date: 2011-01-25
Classification: B41J,H01L

Abstract:
1. A piezoelectric element comprising a piezoelectric film disposed on a substrate and a pair of electrodes disposed in contact with the piezoelectric film and utilizing a bending mode, wherein the piezoelectric film includes domains constituted of a tetragonal crystal and including an a-domain which is formed by a crystal having a (100) plane parallel to the film surface of the piezoelectric film, the a-domains include an A-domain having a normal axis of (001) plane substantially parallel to a principal bending direction of the piezoelectric film and a B-domain having a normal axis of (001) plane substantially perpendicular to the principal bending direction of the piezoelectric film, the A-domains have a volume proportion larger than 50 vol % with respect to the sum of the volume of the A-domains and the volume of the B-domains, and the piezoelectric film is preferably formed by a piezoelectric material represented by a following chemical formula (1): where M represents any one element selected from La, Ca, Ba, Sr, Bi, Sb, W and Nb, and x, xm, y and z represent real numbers respectively satisfying relations 0≦x≦0.2, 1.0≦xm≦1.3, 0.40≦y≦0.65 and 2.5≦z≦3.0.