Piezoelectric element, piezoelectric element application device, and method of manufacturing piezoelectric element
A piezoelectric element includes a first electrode, a piezoelectric layer formed of a first piezoelectric film which is formed on the first electrode and which includes potassium, sodium, and niobium and a plurality of second piezoelectric films which are formed on the first piezoelectric film and which include potassium, sodium, and niobium, and a second electrode formed on the piezoelectric layer, in which the piezoelectric layer is a stack of a plurality of piezoelectric films, the first piezoelectric film has a thickness of 30 nm to 70 nm, a concentration of sodium in each of the piezoelectric films is along a gradient in the film thickness direction with the first electrode side being high and the second electrode side being low.
1. A piezoelectric element comprising:
a first electrode;
a piezoelectric layer formed of a first piezoelectric film formed on the first electrode, a second piezoelectric film formed on the first piezoelectric film, and a third piezoelectric film formed on the second piezoelectric film, each of the first, second, and third piezoelectric films including potassium, sodium, and niobium; and
a second electrode formed on the piezoelectric layer,
wherein the piezoelectric layer is a stacked structure of the first, second, and third piezoelectric films,
the first piezoelectric film has a thickness of 30 nm to 70 nm, and
a concentration of sodium in the first piezoelectric film is greater than a concentration of sodium in the second piezoelectric film, and the concentration of sodium in the second piezoelectric film is greater than a concentration of sodium in the third piezoelectric film.
2. The piezoelectric element according to claim 1 ,
wherein the first piezoelectric film formed on the first electrode is provided without a titanium film being interposed therebetween.
3. A piezoelectric element application device comprising:
the piezoelectric element according to claim 1 .
4. A piezoelectric element application device comprising:
the piezoelectric element according to claim 2 .