A piezoelectric element includes: a first electrode provided on a base; a second electrode; and a piezoelectric layer that is provided between the first electrode and the second electrode and that contains a complex oxide having a perovskite structure and including potassium, sodium, and niobium, where: a surface of the piezoelectric layer on a side of the second electrode is composed of faces of first grains and faces of second grains; a roughness height on the faces of the first grains is larger than a roughness height on the faces of the second grains; and an area occupied by the faces of the first grains is 10.0% or less on the surface of the piezoelectric layer.

Various embodiments of the present disclosure are directed towards a piezoelectric metal-insulator-metal (MIM) device including a piezoelectric structure between a top electrode and a bottom electrode. The piezoelectric layer includes a top region overlying a bottom region. Outer sidewalls of the bottom region extend past outer sidewalls of the top region. The outer sidewalls of the top region are aligned with outer sidewalls of the top electrode. The piezoelectric layer is configured to help limit delamination of the top electrode from the piezoelectric layer.

A transducer includes a first piezoelectric layer; and a second piezoelectric layer that is above the first piezoelectric layer; wherein the second piezoelectric layer is a more compressive layer with an average stress that is less than or more compressive than an average stress of the first piezoelectric layer.

A method for manufacturing an inkjet print head includes determining a misfit strain-electric field crystal phase relation for at least one composition of a piezoelectric material; selecting a misfit strain value and a composition of the piezoelectric material based on the determined misfit strain-electric field crystal phase relation for said at least one composition; and based on the selected misfit strain and the selected composition of the piezoelectric material, forming a base layer and an actuator stack on the base layer, the actuator stack including the piezoelectric material, wherein the base layer and the actuator stack have predetermined properties providing the selected misfit strain value and the selected composition. Thus, an inkjet print head having a piezoelectric actuator that is operated on the basis of a crystal phase change is reliably manufacturable.

A transducer comprising: at least one piezoelectric layer; a first patterned conductive layer that is patterned with a first opening; a second patterned conductive layer that is patterned with a second opening; wherein at least one piezoelectric layer is between the first and the second patterned conductive layers in a stack; and wherein a position of the first opening is staggered relative to a position of the second opening in the stack to mitigate an occurrence of crack propagation through the layers.

A piezoelectric element, in which a piezoelectric material layer has a plurality of crystal particles and a plurality of void portions and, in at least one of two or more of the piezoelectric material layers, when the average thickness in the lamination direction of the piezoelectric material layer is defined as T.sub.P, the average circle-equivalent diameter of the plurality of crystal particles is defined as D.sub.G, the maximum length in the lamination direction of the plurality of void portions not contacting the electrode layers is defined as L.sub.V, and the average thickness of the electrode layers contacting the at least one piezoelectric material layer is defined as T.sub.E, 0.07T.sub.PD.sub.G0.33T.sub.P and T.sub.EL.sub.V0.3T.sub.P are established and the lead content is less than 1000 ppm.

In a piezoelectric element, shift of a resonance point to a low-pitched sound side is achieved. A resonance point of a piezoelectric element moves to a low-pitched sound side when an active region is configured to be surrounded by an inactive region as in the configuration of the piezoelectric element. According to the piezoelectric element whose resonance point is moved to a low-pitched sound side, the piezoelectric element can realize a sound pressure that is sufficiently high for practical use when it is applied to an acoustic device.

A multilayer piezoelectric element includes a laminated body and a lateral electrode. The laminated body includes a piezoelectric layer and an internal electrode layer. The piezoelectric layer is formed along a plane including a first axis and a second axis perpendicular to each other. The internal electrode layer is laminated on the piezoelectric layer. The internal electrode layer has a leading portion exposed to the lateral surface of the laminated body and is electrically connected with the lateral electrode via the leading portion. A dummy electrode layer is formed with a gap to surround the internal electrode layer excluding the leading portion on the plane of the piezoelectric layer. The dummy electrode layer is composed of a material whose thermal shrinkage start temperature is higher than that of a conductive metal constituting the internal electrode layer.

A multilayer piezoelectric element includes a laminated body and a lateral electrode. The laminated body includes a piezoelectric layer and an internal electrode layer. The piezoelectric layer is formed along a plane including a first axis and a second axis perpendicular to each other. The internal electrode layer is laminated on the piezoelectric layer. The internal electrode layer has a leading portion exposed to the lateral surface of the laminated body and is electrically connected with the lateral electrode via the leading portion. Ro is higher than Rc in the the laminated body. Ro is an existence rate of outer circumferential pores existing in the piezoelectric layer located in an outer circumferential part of the internal electrode layer. Rc is an existence rate of central pores existing in a central part of the laminated body.

A piezoelectric element includes first and second electrodes, a first piezoelectric body layer, and a plurality of first through-hole conductors. The first and second electrodes oppose each other. The first piezoelectric body layer is disposed between the first electrode and the second electrode. The plurality of first through-hole conductors penetrates the first piezoelectric body layer and is connected to the first electrode and the second electrode. When seen in an opposing direction of the first and second electrodes, the plurality of first through-hole conductors is arrayed in a matrix.