An ink-jet recording head includes a plurality of recording element substrates each having an ejection pressure generating element configured to generate pressure for ejecting ink from an ink discharge port. The plurality of recording element substrates each include a first surface on which the corresponding ejection pressure generating element is disposed and a second surface, serving as an end surface intersecting with the first surface, being at least partially formed by etching.

In one example, a process for making a micro device structure includes molding a micro device in a monolithic body of material and forming a fluid flow passage in the body through which fluid can pass directly to the micro device.

In an embodiment, a fluid flow structure includes a micro device embedded in a molding, and a fluid feed hole formed through the micro device. A fluid channel is fluidically coupled to the fluid feed hole and includes a first compression molded channel segment and a second material ablated channel segment.

A die for a printhead is provided in examples. The die includes a number of fluidic actuator arrays, proximate to a number of fluid feed holes. A number of address lines are disposed proximate to a number of logic circuits on a low-voltage side of the fluid feed holes. An address decoder circuit is coupled to at least a portion of the address lines to select a fluidic actuator in a fluidic actuator array for firing. The address decoder circuit is customized to select a different address for each fluidic actuator in the fluidic actuator array. A logic circuit triggers a driver circuit located in a high-voltage side of the plurality of fluid feed holes opposite the low-voltage side, based, at least in part, on a bit value for the fluidic actuator array, the fluidic actuator selected by the address decoder circuit, and a firing signal.

Provided is a manufacturing method of a liquid ejection head, and the manufacturing method includes steps of: providing an ejection orifice forming member on one surface of a wafer, in which an energy-generating element is provided on the one surface of the wafer; forming a recess on the other surface of the wafer; and dicing the wafer along a plurality of dicing lines. The plurality of dicing lines include a dicing line extending in one direction and a dicing line extending in a direction crossing the one direction, and the recess is formed on each of positions overlapping the dicing lines except for an intersection part where the dicing line extending in the one direction intersects the dicing line extending in the direction crossing the one direction.

In an example implementation, a printhead includes a die sliver molded into a molding. The die sliver includes a front surface exposed outside the molding and flush with the molding to dispense fluid, and a back surface exposed outside the molding and flush with the molding to receive fluid. Edges of the die sliver contact the molding to form a joint between the die sliver and the molding.

There is provided a liquid jetting apparatus, including: a first pressure chamber and a second pressure chamber arranged in a first direction; a first insulating film covering the first and second pressure chambers; a first piezoelectric element arranged to face the first pressure chamber with the first insulating film being intervened therebetween; a second piezoelectric element arranged to face the second pressure chamber with the first insulating film being intervened therebetween; a trace arranged between the first and the second piezoelectric elements adjacent to each other in the first direction; and a second insulating film covering the trace. An end, in the first direction, of a part of the second insulating film covering the trace between the first piezoelectric element and the second piezoelectric element is positioned inside an end of a partition wall partitioning the first pressure chamber and the second pressure chamber.

A method is provided for manufacturing a piezoelectric device including a piezoelectric element that is disposed above a diaphragm and that has a multilayer structure including a first electrode disposed above the diaphragm, a piezoelectric layer disposed on the first electrode, and a second electrode disposed on the piezoelectric layer. The method includes forming the multilayer structure including the first electrode, the piezoelectric layer, and the second electrode above the diaphragm, forming a voltage application electrode extending outwardly from an end of the second electrode to cover a region located above the piezoelectric layer in an inactive section having no second electrode, applying a voltage between the first electrode and the second electrode, and removing the voltage application electrode.

An inkjet head manufacturing method for an inkjet head that includes a head chip including: a nozzle ejecting ink; and a flow path substrate including an ink flow path which communicates with the nozzle and through which the ink flows, the method including: composite substrate manufacturing that is manufacturing a composite substrate including a plurality of regions which forms flow path substrates by being split; first protective film forming that is forming a first protective film on a surface of the composite substrate and an inner wall surface of the ink flow path; splitting that is splitting the composite substrate into the flow path substrates; and second protective film forming that is forming a second protective film on at least an exposed face in a split face of the flow path substrate generated in the splitting, the exposed face being exposed in a surface of the head chip.

The trouble of removing a protective film such as a poly-paraxylene film from the part not requiring the protective film is reduced. A method of manufacturing a head chip according to an aspect of the present disclosure includes a substrate preparation step of preparing an actuator plate substrate having a jet channel communicated with a nozzle hole configured to jet ink, and a non-jet channel which does not jet the ink, and a protective film formation step of forming a protective film configured to protect a common electrode formed on an inner surface of the jet channel from the ink in a state in which the jet channel is exposed and the non-jet channel is covered after the substrate preparation step.