A fluid-ejection element of a fluid-ejection device includes a chamber layer having a pair of chambers fluidically disconnected from one another within the chamber layer. The fluid-ejection element includes a tophat layer over the chamber layer and fluidically connecting the chambers to define a fluid recirculation path between the chambers. The fluid-ejection element includes a nozzle common to both the chambers.

A liquid discharge head substrate, comprising a discharging element configured to discharge a liquid, a driver configured to drive the discharging element, a conductive protection film covering the discharging element via an insulating film, and a controller connected to the protection film and configured to output a control signal that sets the driver in an inactive state when a change of a voltage of the protection film or a change in a current that flows to the protection film is detected.

The present disclosure includes a method of fabricating a thermal ink jet printhead including depositing a first metal layer having a thickness to form a power bus, deposing a first dielectric layer, forming a via in the first dielectric layer to connect the first metal layer to a second metal layer, depositing the second metal layer, depositing a resistive layer, forming a thermal resistor in the resistive layer, depositing a second dielectric layer, and removing a portion of the second dielectric layer.

A wide array printhead module includes a plurality of printhead die. Each of the printhead die includes a number of sensors to measure properties of a number of elements associated with the printhead die. The wide array printhead module further includes an application specific integrated circuit (ASIC) to command and control each of the printhead die. The ASIC is located off any of the printhead die.

Microfluidic delivery systems for dispensing a fluid composition into the air comprising microfluidic die and at least one heating element that is configured to receive an electrical signal comprising a certain on-time and wave form to deliver a fluid composition into the air.

Provided is a technique that enables voltages to be applied, with high precision, to an electrode layer for inhibition and removal of koge while suppressing increase in the size a substrate. A liquid ejection head substrate includes: electrothermal conversion elements that apply heat to a liquid; an upper electrode part in which a plurality of upper electrodes that protect the electrothermal conversion elements are formed at positions where the upper electrodes come into contact with the liquid; a counter electrode part which is provided to correspond to the upper electrode part and in which a plurality of counter electrodes are formed to be electrically connectable to the upper electrodes via the liquid; and a generation unit that generates a voltage to be applied to at least one of the upper electrode part and the counter electrode part.

A wafer structure including a chip substrate and plural inkjet chips is disclosed. The chip substrate is a silicon substrate fabricated by a semiconductor process on a wafer of at least 12 inches. The inkjet chips are formed on the chip substrate by the semiconductor process and diced into the first inkjet chip and the second inkjet chip. Each of the first inkjet chip and the second inkjet chip includes plural ink-drop generators. Each of the ink-drop generators includes a nozzle. A diameter of the nozzle is in a range between 0.5 micrometers and 10 micrometers. A volume of an inkjet drop discharged from the nozzle is in a range between 1 femtoliter and 3 picoliters. The ink-drop generators form plural longitudinal axis array groups having a pitch and form plural horizontal axis array groups having a central stepped pitch equal to 1/600 inches or less.

A wafer structure is disclosed and includes a chip substrate and at least one inkjet chip having plural ink-drip generators. Each ink-drop generator includes a thermal-barrier layer, a resistance heating layer and a protective layer. The thermal-barrier layer is formed on the chip substrate, the resistance heating layer is formed on the thermal-barrier layer, a part of the protective layer is formed on the resistance heating layer, and the barrier layer is formed on the protective layer. The ink-supply chamber has a bottom in communication with the protective layer, and a top in communication with the nozzle. The thermal-barrier layer has a thickness of 500˜5000 angstroms, the protective layer has a thickness of 150˜3500 angstroms, the resistance heating layer has a thickness of 100˜500 angstroms, the resistance heating layer has a length of 5˜30 microns, and the resistance heating layer has a width of 5˜10 microns.

A wafer structure including a chip substrate and plural inkjet chips is disclosed. The chip substrate is a silicon substrate fabricated by a semiconductor process on a wafer of at least 12 inches. The inkjet chips are formed on the chip substrate by the semiconductor process and diced into the first inkjet chip and the second inkjet chip. Each of the first inkjet chip and the second inkjet chip includes plural ink-drop generators. Each of the ink-drop generators includes a nozzle. A diameter of the nozzle is in a range between 0.5 micrometers and 10 micrometers. A volume of an inkjet drop discharged from the nozzle is in a range between 1 femtoliter and 3 picoliters. The ink-drop generators form plural longitudinal axis array groups having a pitch and form plural horizontal axis array groups having a central stepped pitch equal to 1/600 inches or less.

According to examples, an apparatus may include a fluidic chamber, in which fluid is to be temporarily held. The apparatus may also include a heating component to generate heat to form a drive bubble in the fluid held in the fluidic chamber and a cavitation plate may be provided between the fluidic chamber and the heating component. The cavitation plate may be in communication with the fluidic chamber and may physically separate the fluidic chamber from the heating component to protect the heating component. In addition, a controller may determine a condition in the fluidic chamber based on an electrical signal received from the cavitation plate.