Provided are an MEMS device, a head, and a liquid jet device in which substrates are inhibited from warping, so that a primary electrode and a secondary electrode can be reliably connected to each other. Included are a primary substrate 30 provided with a bump 32 including a primary electrode 34, and a secondary substrate 10 provided with a secondary electrode 91 on a bottom surface of a recessed portion 36 formed by an adhesive layer 35. The primary substrate 10 and the secondary substrate 30 are joined together with the adhesive layer 35, the primary electrode 34 is electrically connected to the secondary electrode 91 with the bump 32 inserted into the recessed portion 36, and part of the bump 32 and the adhesive layer 35 forming the recessed portion 36 overlap each other in a direction in which the bump 32 is inserted into the recessed portion 36.

According to an example, a fluid ejection device may include a membrane including a first column of firing chambers, a second column of firing chambers, and a portioning wall, in which the portioning wall physically separates the first column of firing chambers from the second column of firing chambers. The fluid ejection device may also include a plurality of actuators and a substrate including a respective hole extending through the substrate from each of the firing chambers, in which an actuator of the plurality of actuators is provided in each of the firing chambers.

A wafer structure is disclosed and includes a chip substrate and a plurality of inkjet chips. The chip substrate is a silicon substrate which is fabricated by a semiconductor process on a wafer of at least 12 inches. The plurality of inkjet chips include at least one first inkjet chip and at least one second inkjet chip. The plurality of inkjet chips are directly formed on the chip substrate by the semiconductor process, respectively, and diced into the at least one first inkjet chip and the at least one second inkjet chip, to be implemented for inkjet printing.

A thermal bend actuator includes: a thermoelastic beam for connection to drive circuitry; and a passive beam mechanically cooperating with the thermoelastic beam, such that when a current is passed through the thermoelastic beam, the thermoelastic beam expands relative to the passive beam resulting in bending of the actuator. The thermoelastic beam wherein the thermoelastic beam is comprised of an aluminium alloy. The aluminium alloy comprises a first metal which is aluminium, a second metal, and at least 0.1 at. % of a third metal selected from the group consisting of: copper, scandium, tungsten, molybdenum, chromium, titanium, silicon and magnesium.

A liquid ejection head that includes ejection orifices and is configured by bonding a silicon substrate and a support substrate, flow passages which penetrate a bonding surface between the silicon substrate and the support substrate and through which different types of liquids flow. An in-partition wall space that is open to the bonding surface between the silicon substrate and the support substrate is formed in a partition wall for separating the flow passages. The internal pressure of the in-partition wall space is set to be lower than pressure of the liquid on each of the flow passages.

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 liquid ejection head comprises: a first print element substrate having an ejection port for ejecting a liquid; a support member supporting the first print element substrate; and an adhesive agent provided for adhering the first print element substrate to the support member, wherein the first print element substrate includes a supply port opposed to the support member and communicating with the ejection port, a first surface opposed to the support member and surrounding the supply port, and a second surface opposed to the support member and provided along at least a part of an outer edge of the first surface and retracted from the first surface relative to the support member, and the adhesive agent is filled in a first space between the first surface and the support member, and at least a part of a second space between the second surface and the support member.

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.

There is provided liquid discharging head including; channel member which includes plates stacked in a first direction and adhered to each other via adhesive, and in which individual channels each including nozzle and pressure chamber communicated with the nozzle is formed. The plates include first plate and second plate adhered to adhesion surface of the first plate via the adhesive. Hollows each construct one of the individual channels are opened in the adhesion surface. The hollows are arranged side by side in second direction orthogonal to the first direction in the adhesion surface, and three or more grooves are formed in the adhesion surface between two of the hollows adjacent to each other in the second direction, each of the three or more grooves extending in third direction which is orthogonal to the first direction and which crosses the second direction.

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.