Patent ID: 7845772

Claim:
An actuator device comprising: a piezoelectric element comprising a base layer forming a vibrating plate provided on a surface of a substrate, a lower electrode provided the base layer, a piezoelectric layer provided on the lower electrode, and an upper electrode provided on the piezoelectric layer; wherein the lower electrode is comprised of a precious metal; wherein the ratio Z 1 /Z 2 between the intensity Z 1 of oxygen ions and the intensity Z 2 of ions of the precious metal detected at a surface of the lower electrode facing the substrate is 0.2 or more when a cross-section of the lower electrode is examined using secondary ion mass spectroscopy (SIMS), and wherein the base layer is comprised of at least one material selected from a the group of SiO 2 , ZrO 2 , and Zr 1-x M x O y (where 0.01≦X≦0.15, Y=2.0±α, α is a stoichiometrically allowed value, and M is an IIA group element, an IIIA group element, or an IIIB group element).