A nozzle plate of a fluid ejection head for a fluid ejection device, a fluid ejection head containing the nozzle plate, and a method for making the fluid ejection head containing the nozzle plate. The nozzle plate contains two or more arrays of nozzle holes therein and a barrier structure disposed on an exposed surface of the nozzle plate between adjacent arrays of nozzle holes, wherein the barrier structure deters cross-contamination of fluids between the adjacent arrays of nozzle holes.

A piezoelectric film includes a plurality of laminated main baking unit PZT layers. A first seed layer is present at a lower surface side of a lowermost main baking unit PZT layer. A second seed layer is interposed between two adjacent main baking unit PZT layers at an intermediate position between the lowermost main baking unit PZT layer and an uppermost main baking unit PZT layer.

An actuator includes a deformable thin-film member having an opening, an electromechanical conversion element disposed at a periphery of the opening of the deformable thin-film member, an insulating film covering the electromechanical conversion element, a protective film over a surface of the insulating film, the protective film covering the surface of the insulating film and a surface of an electrode wiring connected to the electromechanical conversion element, and an adhesion improving film disposed between the electrode wiring and the protective film.

A liquid discharging head includes a nozzle configured to discharge liquid, a pressure chamber communicated with the nozzle, and an individual channel communicated with the pressure chamber through a narrow part. The liquid discharging head also includes a common channel communicated with the individual channel, an energy generation element configured to generate energy, and a diaphragm configured to convey the energy to the pressure chamber. A metal oxide film is formed at inner walls of the nozzle, the pressure chamber, the narrow part, the diaphragm, and the individual channel, and a hydroxyl group has come out from the metal oxide film.

A substrate with an electrical connection section or a substrate for liquid ejection head comprises a wiring layer, a diffusion prevention layer laid on the wiring layer and a connection member laid on the diffusion prevention layer for establishing an electrical connection to an outside. An insulation layer having a wiring-layer-exposing opening is arranged on the wiring layer and the diffusion prevention layer is arranged in the opening, while the connection member is arranged on the diffusion prevention layer so as to cover an outer peripheral edge of the diffusion prevention layer.

An actuator includes a substrate, a diaphragm on the substrate, a lower electrode on the diaphragm, a piezoelectric body on the lower electrode, and an upper electrode on the piezoelectric body. A ratio of lead (Pb) and zirconium (Zr) in atomic percent (atm %) present at a grain boundary in the piezoelectric body satisfies a relation of Pb/Zr>1.7.

A substrate joined body including: a first substrate; a second substrate; an organic film that comprises silicon and carbon and joins the first substrate and the second substrate; and a protective film that comprises an inorganic element and is formed over the organic film from at least a part of the surface of the first substrate and at least a part of the surface of the second substrate, wherein the protective film comprises a region in which the ratio of carbon to silicon based on atomic percentage is from 0.0 to 5.0 in a region within 50 nm in a thickness direction from a surface of the organic film on the protective film side, when the surface is measured by X-ray photoelectron spectroscopy.

There is provided a piezoelectric actuator, including: a vibration plate; a first piezoelectric body; a second piezoelectric body; a first electrode disposed on a first surface of the first piezoelectric body; a second electrode disposed on a second surface of the second piezoelectric body; an intermediate electrode disposed on an intermediate surface of the first piezoelectric body and overlapping with the first and second electrodes; an intermediate trace connected to the intermediate electrode on the intermediate surface and drawn out to one side in a first direction beyond the first piezoelectric body and the second piezoelectric body; a first trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace; and a second trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace.

Disclosed is a method of manufacturing, a metal nozzle plate, in which is formed a nozzle for discharging a liquid and that is to be bonded with adhesive to a head chip provided with an actuator for discharging the liquid, the method including: forming the nozzle in a metal plate-like member; forming a groove in the metal plate-like member; and performing exterior processing with respect to the nozzle plate.

A flow path member includes a first substrate having a first surface that has a flow path, and includes a second substrate having a second surface opposing the first surface. In the flow path member in which the first and second substrates are joined together with adhesive provided between the first and second surfaces, a groove is formed in at least one of the first and second surfaces. When the first substrate is viewed from a direction orthogonal to the first surface, the flow path is disposed on a groove inner side. The groove has a first portion having a first depth and a second portion having a second depth shallower than the first depth. The second portion is that portion of the groove existing inside a region surrounded by an outer edge of the first surface and extension lines of two sides that form a flow path corner.