Abstract: A liquid ejection head includes: a piezoelectric body; an vibration plate to be vibrated by a drive of the piezoelectric body; and a pressure chamber substrate including a pressure chamber which applies a pressure to a liquid by an vibration of the vibration plate; the pressure chamber substrate, the vibration plate, and the piezoelectric body are laminated in this order; and the vibration plate includes: a first layer containing silicon as a constituent element, a second layer which is disposed between the first layer and the piezoelectric body and which contains as a constituent element, a metal element selected from chromium, titanium, and aluminum, and a third layer which is disposed between the second layer and the piezoelectric body and which contains zirconium as a constituent element.

Abstract: A liquid discharge head includes: a nozzle plate provided with a nozzle hole that discharges a liquid; a silicon substrate provided with a pressure chamber that is connected with the nozzle hole; a diaphragm provided on the silicon substrate; and a piezoelectric element that is provided on the diaphragm and that changes a volume of the pressure chamber, where: the diaphragm includes a zirconium oxide layer; the zirconium oxide layer has (?111) preferred orientation; and in X-ray diffraction of the diaphragm, a difference between a position of (002) peak of the zirconium oxide layer and a position of (220) peak of the silicon substrate is 13.26° or more and 13.30° or less.

Abstract: A recording head includes a pressure chamber and a piezoelectric actuator configured to change a volume of the pressure chamber. The piezoelectric actuator includes a vibration plate forming one wall surface of the pressure chamber, a lower electrode formed on the vibration plate, a piezoelectric body formed on the lower electrode, and an upper electrode formed on the piezoelectric body and the vibration plate. When viewed from a ±Z direction orthogonal to the vibration plate, the lower electrode and the piezoelectric body do not overlap a central portion of the pressure chamber, when viewed from the ±Z direction, the lower electrode, the piezoelectric body, and the upper electrode overlap an end portion of the pressure chamber, and when viewed from the ±Z direction, the upper electrode overlaps the central portion of the pressure chamber.

Abstract: A method for producing a piezoelectric actuator including forming a vibration plate, forming a first electrode on the vibration plate, forming a piezoelectric layer on the first electrode, and forming a second electrode on the piezoelectric layer, wherein the forming the vibration plate has a single layer forming step including forming a metal layer containing zirconium by a gas phase method, and forming a metal oxide layer by firing the metal layer, the single layer forming step is repeated, thereby forming the vibration plate in which the metal oxide layers are stacked, and the metal oxide layer has a thickness less than 200 nm.

Abstract: A liquid ejecting head including a flow path forming substrate in which a pressure chamber is formed, a diaphragm, and a piezoelectric actuator. The piezoelectric actuator includes an active portion in which a piezoelectric layer is interposed between a first electrode and a second electrode. The active portion, in plan view, overlaps at least a portion of the pressure chamber and is provided so as to extend to an outside of the pressure chamber. The pressure chamber is formed so that, the closer to the piezoelectric actuator in a layered direction of the flow path forming substrate and the diaphragm, a width of the pressure chamber in a direction intersecting the layered direction becomes smaller.

Abstract: A liquid ejecting head including a flow path forming substrate in which a pressure chamber in communication with a nozzle is formed, a diaphragm formed on the flow path forming substrate, and a piezoelectric actuator including a first electrode, a piezoelectric layer, and a second electrode that are formed on the diaphragm. In the liquid ejecting head, a center portion of the diaphragm is not provided with an active portion, which is a portion where the piezoelectric layer is interposed between the first electrode and the second electrode, a protective film that covers the diaphragm is formed in the center portion, and compressive stress of the protective film is larger than that of the diaphragm.

Abstract: A liquid discharge head includes: a nozzle plate provided with a nozzle hole that discharges a liquid; a silicon substrate provided with a pressure chamber that is connected with the nozzle hole; a diaphragm provided on the silicon substrate; and a piezoelectric element that is provided on the diaphragm and that changes a volume of the pressure chamber, where: the diaphragm includes a zirconium oxide layer; the zirconium oxide layer has (?111) preferred orientation; and in X-ray diffraction of the diaphragm, a difference between a position of (002) peak of the zirconium oxide layer and a position of (220) peak of the silicon substrate is 13.26° or more and 13.30° or less.

Abstract: Provided is a piezoelectric element including a first electrode provided above a substrate, a piezoelectric layer provided above the first electrode, containing potassium, sodium, and niobium, and having a perovskite structure, and a second electrode provided above the piezoelectric layer. In a case where the piezoelectric layer is divided into two portions at a center thereof in a thickness direction, the piezoelectric layer includes a first portion on the first electrode side and a second portion on the second electrode side. The piezoelectric layer includes line defects. A density of the line defects in the second portion is higher than a density of the line defects in the first portion.

Abstract: A piezoelectric element includes: a first electrode containing crystal grains; a piezoelectric layer which contains potassium, sodium, and niobium and which is provided above the first electrode; and a second electrode provided above the piezoelectric layer, and the average grain diameter of the crystal grains is less than 550 nm.

Abstract: Provided is a piezoelectric element including a first electrode provided above a substrate, a piezoelectric layer including a plurality of crystal grains containing potassium, sodium, and niobium and provided above the first electrode, and a second electrode provided above the piezoelectric layer. An atom concentration NK1 (atm %) of potassium contained in grain boundaries of the crystal grains and an atom concentration NK2 (atm %) of potassium contained in the crystal grains satisfy a relationship of 1.0<NK1/NK2?2.4.

Abstract: Provided is a piezoelectric element including a first electrode provided above a substrate, a piezoelectric layer provided above the first electrode, containing potassium, sodium, and niobium, and having a perovskite structure, and a second electrode provided above the piezoelectric layer. In a case where the piezoelectric layer is divided into two portions at a center thereof in a thickness direction, the piezoelectric layer includes a first portion on the first electrode side and a second portion on the second electrode side. The piezoelectric layer includes line defects. A density of the line defects in the second portion is higher than a density of the line defects in the first portion.

Abstract: A piezoelectric element includes: a first electrode containing crystal grains; a piezoelectric layer which contains potassium, sodium, and niobium and which is provided above the first electrode; and a second electrode provided above the piezoelectric layer, and the average grain diameter of the crystal grains is less than 550 nm.