A conduction structure includes a device substrate (first substrate), an IC (second substrate) having an upper surface and an end surface, a sealing plate (third substrate) having an upper surface and an end surface, a conductive layer having a first part provided on an upper surface of the device substrate, a second part provided on the end surface of the IC and connected to the first part, a third part provided on the upper surface of the IC and connected to the second part, and a fourth part provided on the end surface of the sealing plate and connected to both of the first part and the second part, and a plating layer overlapped with the conductive layer.

A piezoelectric material that does not contain lead and has excellent piezoelectric constant and mechanical quality factor in a device driving temperature range (30 C. to 50 C.) is provided. A piezoelectric material includes a main component containing a perovskite metal oxide represented by following general formula (1), and a first auxiliary component containing Mn, wherein an amount of the contained Mn is 0.002 moles or more and 0.015 moles or less relative to 1 mole of the metal oxide.
(Ba.sub.1-yBi.sub.y).sub.a(Ti.sub.1-x-zZr.sub.xFe.sub.z)O.sub.3(1)
(where 0.010x0.060, 0.001y0.015, 0.001z0.015, 0.950y/z1.050, and 0.986a1.020).

A method for manufacturing a liquid jetting apparatus includes: a wire formation step of forming a wire so that a part of the wire covers a piezoelectric film; and an electrode formation step of forming a second electrode, after the wire formation step, on a surface of the piezoelectric film on a side far from a vibration film so as to be in electrical conduction with the wire. The liquid jetting apparatus includes: a flow passage formation portion; and a piezoelectric actuator having the vibration film provided on the flow passage formation portion, the piezoelectric film arranged on the vibration film, a first electrode arranged on a surface of the piezoelectric film on a side near to the vibration film, the second electrode arranged on the surface of the piezoelectric film on the side far from the vibration film, and the wire connected to the second electrode.

The piezoelectric body is configured to have a layered structure such that a plurality of unit layers are stacked in a film thickness direction, and each of the unit layers is formed of a first layer on which the displacement is relatively easy to occur, and a second layer which has a high concentration of Zr as compared with the first layer. In addition, when composition ratio Ti/(Zr+Ti) of Zr to Ti in each of the first layer and the second layer is set as Cr1 and Cr2, the composition ratio of each layer is adjusted so as to satisfy the following conditions (1) to (3).
0.41Cr10.81(1)
0.1Cr1Cr20.3(2)
Cr1>Cr2(3)

At an area corresponding to a pressure chamber, the width of a lower electrode film in a nozzle row direction is narrower than the width of the pressure chamber in the same direction. A vibrating plate at the area corresponding to a pressure chamber includes an area P1, an area P2, and an area P3. The area P1 is an area on which the piezoelectric layer to be an activation portion is stacked. The area P2 is an area on which the piezoelectric layer to be an inactivation portion is stacked. The area P3 is an area on which the piezoelectric layer is not stacked. When the thicknesses of the vibrating plate at the areas P1, P2 and P3 are set to, respectively, t1, t2, and t3, the following expression is satisfied: t1>t2t3 (1).

A vibration layer is formed by the AD method on a cavity plate before forming pressure chambers, a common electrode is formed on the vibration layer, and a piezoelectric layer is formed on the common electrode by the AD method. Subsequently, the pressure chambers are formed in the cavity plate by the etching. After that, individual electrodes are formed on the piezoelectric layer. Subsequently, the stack of the cavity plate, the vibration layer, the common electrode, the piezoelectric layer, and the individual electrodes is heated at about 850 C. to simultaneously perform the annealing of the piezoelectric layer and the sintering of the individual electrodes and the common electrode. Accordingly, the atoms of the cavity plate are suppressed from being diffused into the driving portions of the piezoelectric layer.

A liquid ejection head includes a nozzle plate, a channel plate, a common-liquid-chamber member, and a deformable damper area. The nozzle plate includes plural nozzles to eject droplets of liquid. The channel plate includes individual liquid chambers communicated with the nozzles. The common-liquid-chamber member includes a common liquid chamber to supply the liquid to the individual liquid chambers. The deformable damper area forms a wall face of the common liquid chamber. The channel plate has an end in a direction perpendicular to a nozzle array direction in which the nozzles are arrayed. The end is opposed to a portion of the damper area and has a relief at a side facing the damper area to permit deformation of the damper area.

A channel substrate includes a plurality of individual channels and a plurality of linear machining marks. The plurality of individual channels is arrayed in row. The plurality of linear machining marks is substantially parallel to a direction in which the plurality of individual channels is arrayed in row.

According to an embodiment, a liquid ejection head includes a vibration plate, a nozzle plate with nozzles, a plurality of pressure chambers between the vibration plate and the nozzle plate, and a piezoelectric member on a side of the vibration plate opposite of the pressure chambers. The piezoelectric member includes drive elements in a first area opposed to the pressure chambers via the vibration plate and configured to selectively vibrate the vibration plate to generate pressure changes in the pressure chambers and a plurality of pillar elements in a second area outside the first area and not opposed to the pressure chambers. The vibration plate includes at least one alignment mark at a position opposed to the second area of the piezoelectric member.

A liquid discharging head includes a nozzle plate including a nozzle substrate having a plurality of nozzle holes to discharge a liquid therethrough and a plurality of dimples on the discharging surface of the nozzle substrate to hold a liquid repellent material inside the plurality of dimples in a flowable manner and a liquid repellency film formed by the liquid repellent material on the discharging surface of the nozzle substrate.