A method for manufacturing a device for ejecting a fluid, including the steps of: forming, in a first semiconductor wafer that houses a nozzle of the ejection device, a first structural layer; removing selective portions of the first structural layer to form a first portion of a chamber for containing the fluid; removing, in a second semiconductor wafer that houses an actuator of the ejection device, selective portions of a second structural layer to form a second portion of the chamber; and coupling together the first and second semiconductor wafers so that the first portion directly faces the second portion, thus forming the chamber. The first portion defines a part of volume of the chamber that is larger than a respective part of volume of the chamber defined by the second portion.

A method for producing a liquid transport apparatus is disclosed. The liquid transport apparatus includes a pressure chamber plate, a ceramics layer formed on a surface of the pressure chamber plate, a piezoelectric layer formed on the ceramics layer, and an electrode formed on the piezoelectric layer. The ceramics layer is formed by heating an insulating ceramic material at a temperature lower than an annealing temperature of the piezoelectric layer. Accordingly, the atoms of the pressure chamber plate are suppressed from being diffused into the piezoelectric layer.

A highly reliable liquid ejection head comprises a substrate made of silicon and having a first surface and a second surface opposite to the first surface, an ejection port forming member bonded to the first surface of the substrate and formed with an ejection port for ejecting liquid, and a bonded member configured to be bonded to the second surface of the substrate. A through flow path is formed in the substrate, which is configured to pass through the substrate and to supply liquid to the ejection port. A first protective film made of a metal oxide is formed on an inner surface of the through flow path, and a second protective film made of a silicon compound is formed on all of the second surface of the substrate.

A channel member includes a first substrate in which a channel is formed from a first surface, and a second substrate having a second surface facing the first surface, wherein the first substrate and the second substrate are bonded to each other with an adhesive between the first surface and the second surface, wherein the channel has a polygonal shape when viewed from a direction orthogonal to the first surface, wherein the channel includes a first portion on the first surface side and a second portion that communicates with the first portion, wherein an aperture area of the second portion is larger than an aperture area of the first portion when viewed from the direction orthogonal to the first surface, and wherein the adhesive is present on a step surface between the first portion and the second portion and at vertices of the polygonal shape.

A piezoelectric device includes a piezoelectric body, a vibration plate that vibrates when the piezoelectric body is driven, a first electrode positioned between the piezoelectric body and the vibration plate, and a second electrode positioned to be separated from the first electrode by the piezoelectric body. The piezoelectric body has an active portion that is a part sandwiched between the first electrode and the second electrode in a first direction along a thickness direction of the piezoelectric body, and a change width of a dC/dV value, which represents a change in capacitance with respect to a change in a voltage applied along a second direction orthogonal to the first direction, from one end of the active portion on a side of the first electrode to the other end of the active portion on a side of the second electrode in the first direction is 10% or less.

A head chip, a liquid jet head, a liquid jet recording device, and a method of manufacturing a head chip each capable of ensuring the tolerance of the displacement between nozzle holes and communication holes while ensuring the bonding area between an actuator plate and an intermediate plate are provided. The head chip according to an aspect of the present disclosure includes an actuator plate, a nozzle plate disposed so as to be opposed to the actuator plate, and an intermediate plate disposed between the actuator plate and the nozzle plate. The communication holes each include a groove part having a lower-side opening part opening toward the nozzle hole, and a penetrating part having an upper-side opening part opening toward an ejection channel. A dimension in the X direction in the upper-side opening part is larger than a dimension in the X direction in the upper-side opening part, and a dimension in the X direction in the upper-side opening part is no larger than a dimension in the X direction of the channel opening part opening on a channel opening surface of the ejection channel.

There are provided a head chip, a liquid jet head, a liquid jet recording device, and a method of manufacturing a head chip each capable of homogenously forming protective films on inner surfaces of channels while dealing with miniaturization of the channels and a decrease in pitch of the channels. The head chip according to an aspect of the present disclosure includes an actuator plate having a plurality of ejection channels arranged, a common electrode formed on an inner surface of the ejection channel, a first protective film disposed so as to cover the common electrode on the inner surface of the ejection channel, an intermediate plate which has ejecting communication holes and ejection-side introduction ports respectively communicated with the plurality of ejection channels, and which is disposed so as to face a channel opening surface on which the ejection channels open in the actuator plate, and a nozzle plate which has a plurality of nozzle holes configured to eject ink, and which is disposed at an opposite side to the actuator plate with respect to the intermediate plate in a state in which the ejecting communication holes are respectively communicated with the nozzle holes, and the ejection-side introduction ports are closed.

A substrate having a recessed portion, a diaphragm, and a piezoelectric actuator are provided, the diaphragm includes a first layer containing silicon as a constituent element, and a third layer disposed between the first layer and the piezoelectric actuator and containing zirconium as a constituent element, and a laminated side surface of the first layer and the third layer is covered with a moisture-resistant protective film containing at least one selected from the group made of oxide, nitride, metal, and diamond-like carbon.

Process for manufacturing a microfluidic device, wherein a sacrificial layer is formed on a semiconductor substrate; a carrying layer is formed on the sacrificial layer; the carrying layer is selectively removed to form at least one release opening extending through the carrying layer; a permeable layer of a permeable semiconductor material is formed in the at least one release opening; the sacrificial layer is selectively removed through the permeable layer to form a fluidic chamber; the at least one release opening is filled with non-permeable semiconductor filling material, forming a monolithic body having a membrane region; an actuator element is formed on the membrane region and a cap element is attached to the monolithic body and surrounds the actuator element.

A liquid discharge head includes a nozzle member. The nozzle member includes a nozzle, a deformable laminar member, and an electromechanical transducer. The nozzle discharges liquid. The deformable laminar member has an opening forming the nozzle. The electromechanical transducer is disposed around the opening. The nozzle member is warped with respect to a discharge-side plane of the nozzle member in a surrounding area of the nozzle when no voltage is applied to the electromechanical transducer.