Patent ID: 9324931
Filing Date: 2016-04-26
CPC Classification: H01L

Claim Text:
1. A piezoelectric device comprising: a first electrode film; a piezoelectric film disposed on the first electrode film; and a second electrode film disposed on the piezoelectric film, wherein an oxidation-reduction potential of a metal element constituting the first and second electrode films is higher than oxidation-reduction potentials of all metal elements constituting the piezoelectric film, and the piezoelectric film has a composition represented by formula (1) below and contains 1% by mass or less of MnO relative to the composition where x, y, z, w, v, u, and m in formula (1) satisfy 0.4<x≦0.7, 0.02≦y≦0.11, 0.5≦x+y<0.75, 0<z≦0.28, 0<w≦0.02, 0.02≦v≦0.11, 0.02≦u≦0.11, and 0.95≦m<1.2.