Piezoelectric elements, piezoelectric element application devices, and methods for manufacturing piezoelectric elements

摘要

PROBLEM TO BE SOLVED: To provide: a piezoelectric element having a KNN layer formed in a wet method, which is a piezoelectric material layer with a uniform compositional distribution in each of an in-plane direction and a film thickness direction, and a piezoelectric element application device and a method for manufacturing the piezoelectric element.SOLUTION: A piezoelectric element comprises: a first electrode; a first piezoelectric film formed on the first electrode, and containing potassium, sodium and niobium; a piezoelectric material layer formed on the first piezoelectric film and having a plurality of second piezoelectric films containing the potassium, the sodium and the niobium; and a second electrode formed on the piezoelectric material layer. The piezoelectric material layer is composed of a laminate of the plurality of piezoelectric films. The first piezoelectric film has a thickness of 30 or more and of 70 nm or less. In each piezoelectric film, a sodium concentration is inclined in a film thickness direction which is high on a first electrode side, and low on a second electrode side.SELECTED DRAWING: Figure 15