Abstract: Provided are a piezoelectric inkjet printhead and a method of manufacturing the same. The piezoelectric inkjet printhead includes first and second single-crystalline silicon substrates. An ink flow path is disposed in a first surface of the first substrate. The ink flow path includes an ink introduction port, a manifold for supplying ink, a plurality of pressure chambers filled with ink to be ejected, a plurality of restrictors for connecting the manifold with the plurality of pressure chambers, respectively, and a plurality of nozzles for ejecting ink. The second substrate is bonded to the first substrate to thereby complete the ink flow path. A plurality of piezoelectric actuators are disposed on a second surface of the first substrate to correspond to each of the pressure chambers and provide drivability required for ejecting ink to the respective pressure chambers.

Abstract: A piezoelectric ink-jet printhead and a method for manufacturing the same, wherein the piezoelectric ink-jet printhead is formed by stacking three monocrystalline silicon substrates on one another and adhering them to one another. The three substrates include an upper substrate, through which an ink supply hole is formed and a pressure chamber is formed on a bottom surface thereof; an intermediate substrate, in which an ink reservoir and a damper are formed; and a lower substrate, in which a nozzle is formed. A piezoelectric actuator is monolithically formed on the upper substrate. A restrictor, which connects the ink reservoir to the pressure chamber in flow communication, may be formed on the upper substrate or intermediate substrate.

Abstract: A piezoelectric actuator includes a first electrode layer, a piezoelectric layer and a second electrode layer. The first electrode layer is formed on a vibration plate. The piezoelectric layer is formed on the first electrode layer, the piezoelectric layer comprising piezoelectric particles formed on the surface of a self-assembled monolayer. The second electrode layer is formed on the piezoelectric layer to face the first electrode layer. Thus, a self-assembled monolayer is formed, so that the piezoelectric characteristics of a piezoelectric layer and/or the stiffness of the piezoelectric layer may be increased. Thus, piezoelectric characteristics of the piezoelectric actuator may be enhanced, and the required voltage, which is required to realize a proper deformation amount of the piezoelectric actuator, may be decreased. Moreover, the stiffness of the piezoelectric actuator may be increased, so that the vibration remaining at the piezoelectric actuator may be minimized even though the driving is finished.

Abstract: A piezoelectric inkjet printhead including an upper substrate formed of a single crystal silicon substrate or an SOI substrate and having an ink inlet therethrough, and a lower substrate formed of an SOI substrate having a sequentially stacked structure with a first silicon layer, an intervening oxide layer, and a second silicon layer in which a manifold, pressure chambers, and dampers are formed in the second silicon layer by wet or dry etching, and nozzles are formed through the intervening oxide layer and the first silicon layer by dry etching, and a method of manufacturing the same.

Abstract: A piezoelectric actuator of an inkjet head and a method of forming the piezoelectric actuator. The piezoelectric actuator is formed on a vibration plate to provide a driving force to each of a plurality of pressure chambers. The piezoelectric actuator includes a lower electrode formed on the vibration plate, a piezoelectric layer formed on the lower electrode at a position corresponding to each of the pressure chambers, a supporting pad formed on the lower electrode, the supporting pad contacting one end of the piezoelectric layer and extending away from the one end of the piezoelectric layer, and an upper electrode extending from a top surface of the piezoelectric layer to a top surface of the supporting pad. The upper electrode is bonded to a driving circuit above the supporting pad to receive a voltage from the driving circuit. The piezoelectric layer may have substantially the same length as the pressure chamber.

Abstract: A piezoelectric inkjet printhead including an upper substrate, having an ink inlet, a manifold connected with the ink inlet, and a plurality of pressure chambers arranged along at least one side of the manifold, wherein the ink inlet passes through the upper substrate, and the manifold and the pressure chambers are formed in a lower surface of the upper substrate, a lower substrate disposed directly adjacent the upper substrate, the lower substrate having a plurality of restrictors each connecting the manifold with one end of each of the pressure chambers, and a plurality of nozzles each being formed in a position of the lower substrate that corresponds to the other end of each of the pressure chambers to vertically pass through the lower substrate, wherein the plurality of restrictors are formed in an upper surface of the lower substrate, and a plurality of piezoelectric actuators.

Abstract: A piezoelectric inkjet printhead including an upper substrate formed of a single crystal silicon substrate or an SOI substrate and having an ink inlet therethrough, and a lower substrate formed of an SOI substrate having a sequentially stacked structure with a first silicon layer, an intervening oxide layer, and a second silicon layer in which a manifold, pressure chambers, and dampers are formed in the second silicon layer by wet or dry etching, and nozzles are formed through the intervening oxide layer and the first silicon layer by dry etching, and a method of manufacturing the same.

Abstract: A piezoelectric actuator of an inkjet head and a method of forming the piezoelectric actuator. The piezoelectric actuator is formed on a vibration plate to provide a driving force to each of a plurality of pressure chambers. The piezoelectric actuator includes a lower electrode formed on the vibration plate, a piezoelectric layer formed on the lower electrode at a position corresponding to each of the pressure chambers, a supporting pad formed on the lower electrode, the supporting pad contacting one end of the piezoelectric layer and extending away from the one end of the piezoelectric layer, and an upper electrode extending from a top surface of the piezoelectric layer to a top surface of the supporting pad. The upper electrode is bonded to a driving circuit above the supporting pad to receive a voltage from the driving circuit. The piezoelectric layer may have substantially the same length as the pressure chamber.

Abstract: A method of forming a piezoelectric actuator of an inkjet head formed on a vibrating plate to provide a driving power for ejecting ink to each of pressure chambers is provided. The method includes forming a lower electrode on a vibrating plate, forming a piezoelectric layer on the lower electrode to be located above each of pressure chambers, forming a protecting layer covering the lower electrode and the piezoelectric layer, exposing an upper surface of the piezoelectric layer by decreasing a thickness of the protecting layer and the piezoelectric layer, forming an upper electrode on the upper surface of the piezoelectric layer, removing the protecting layer. According to the present invention, since the piezoelectric layer having a flat upper surface is formed in uniform figure, area and thickness of the upper electrode formed thereon is uniformly controlled.

Abstract: A method of forming a piezoelectric actuator of an inkjet head formed on a vibrating plate to provide a driving power for ejecting ink to each of pressure chambers is provided. The method includes forming a lower electrode on a vibrating plate, forming a piezoelectric layer on the lower electrode to be located above each of pressure chambers, forming a protecting layer covering the lower electrode and the piezoelectric layer, exposing an upper surface of the piezoelectric layer by decreasing a thickness of the protecting layer and the piezoelectric layer, forming an upper electrode on the upper surface of the piezoelectric layer, removing the protecting layer. According to the present invention, since the piezoelectric layer having a flat upper surface is formed in uniform figure, area and thickness of the upper electrode formed thereon is uniformly controlled.

Abstract: Provided are a nozzle plate of an inkjet printhead and a method of manufacturing the same. The nozzle plate includes: a substrate including a plurality of nozzles; and a plurality of first grooves formed on the surface of a substrate around the nozzles. In this structure, ink remaining on the surface of the nozzle plate can be efficiently removed.

Abstract: Provided are a piezoelectric inkjet printhead and a method of manufacturing the same. The piezoelectric inkjet printhead includes first and second single-crystalline silicon substrates. An ink flow path is disposed in a first surface of the first substrate. The ink flow path includes an ink introduction port, a manifold for supplying ink, a plurality of pressure chambers filled with ink to be ejected, a plurality of restrictors for connecting the manifold with the plurality of pressure chambers, respectively, and a plurality of nozzles for ejecting ink. The second substrate is bonded to the first substrate to thereby complete the ink flow path. A plurality of piezoelectric actuators are disposed on a second surface of the first substrate to correspond to each of the pressure chambers and provide drivability required for ejecting ink to the respective pressure chambers.

Abstract: In a piezoelectric ink-jet printhead, and a method of manufacturing a nozzle plate, the piezoelectric ink-jet printhead includes a flow path plate having an ink flow path including pressure chambers to be filled with ink to be ejected, a piezoelectric actuator formed on an upper surface of the flow path plate and for supplying a driving force for ink ejection to the pressure chambers, and a nozzle plate bonded to a lower surface of the flow path plate including nozzles for ejecting ink from the pressure chambers bored through the nozzle plate. The printhead may further include a heater formed on a lower surface of the nozzle plate for heating ink in the ink flow path and/or a temperature detector formed on a lower surface of the nozzle plate or on an upper surface of the flow path plate.

Abstract: A silicon direct bonding (SDB) method by which void formation caused by gases is suppressed. The SDB method includes: preparing two silicon substrates having corresponding bonding surfaces; forming trenches having a predetermined depth in at least one bonding surface of the two silicon substrates; forming gas discharge outlets connected to the trenches on at least one of the two silicon substrates to vertically penetrate the bonding surface; cleaning the two silicon substrates; closely contacting the two silicon substrates to each other; and thermally treating the two substrates to bond them to each other. The trenches are formed along at least a part of a plurality of dicing lines, and both ends of the trenches are clogged. Gases generated during a thermal treatment process can be smoothly and easily discharged through the trenches and the gas discharge outlet such that a void is prevented from being formed in the junctions of the two silicon substrates due to the gases.

Abstract: A piezoelectric type inkjet printhead includes an upper substrate including a pressure chamber to be filled with ink that is to be ejected, a reservoir to store ink that flowed in from an ink container, a restrictor connect the reservoir to one end of the pressure chamber, an intermediate substrate comprising a damper formed on a portion of the intermediate substrate, which corresponds to other end of the pressure chamber, a lower substrate comprising a nozzle to eject ink and formed in a portion of the lower substrate, which corresponds to the damper, a hydrophobic layer formed on a bottom of the lower substrate, and a piezoelectric actuator formed on the upper substrate to supply driving power to eject ink to the pressure chamber, wherein the nozzle is formed in the lower substrate at a predetermined depth from a bottom surface of the lower substrate.

Abstract: A piezoelectric actuator for providing a driving force to a pressure chamber of an ink-jet printhead for ejecting ink by deforming a vibration plate, the vibration plate forming an upper wall of the pressure chamber, the piezoelectric actuator including a lower electrode formed on the vibration plate, a piezoelectric film having either: (a) peripheral portions, the piezoelectric film formed on the lower electrode at a position that corresponds to the pressure chamber and having a space between the peripheral portions and the lower electrode, or (b) a lateral surface, the piezoelectric film formed on the lower electrode at a position that corresponds to the pressure chamber, the lateral surface of the piezoelectric film substantially forming a right angle with respect to a top surface of the lower electrode, and an upper electrode formed on the piezoelectric film for applying a voltage to the piezoelectric film.

Abstract: A nozzle plate for an inkjet head and a method of manufacturing the nozzle plate includes a silicon substrate having a nozzle, a thermally oxidized silicon layer formed on an outer surface of the silicon substrate and an inner wall of the nozzle, an adhesion layer deposited on the thermally oxidized silicon layer formed on the outer surface of the silicon substrate and formed of silicon oxide, and an ink-repellent coating layer deposited on the adhesion layer.

Abstract: A piezoelectric actuator of an inkjet head and a method of forming the piezoelectric actuator. The piezoelectric actuator is formed on a vibration plate to provide a driving force to each of a plurality of pressure chambers. The piezoelectric actuator includes a lower electrode formed on the vibration plate, a piezoelectric layer formed on the lower electrode at a position corresponding to each of the pressure chambers, a supporting pad formed on the lower electrode, the supporting pad contacting one end of the piezoelectric layer and extending away from the one end of the piezoelectric layer, and an upper electrode extending from a top surface of the piezoelectric layer to a top surface of the supporting pad. The upper electrode is bonded to a driving circuit above the supporting pad to receive a voltage from the driving circuit. The piezoelectric layer may have substantially the same length as the pressure chamber.

Abstract: A method of forming a piezoelectric actuator of an inkjet head formed on a vibrating plate to provide a driving power for ejecting ink to each of pressure chambers is provided. The method includes forming a lower electrode on a vibrating plate, forming a piezoelectric layer on the lower electrode to be located above each of pressure chambers, forming a protecting layer covering the lower electrode and the piezoelectric layer, exposing an upper surface of the piezoelectric layer by decreasing a thickness of the protecting layer and the piezoelectric layer, forming an upper electrode on the upper surface of the piezoelectric layer, removing the protecting layer. According to the present invention, since the piezoelectric layer having a flat upper surface is formed in uniform figure, area and thickness of the upper electrode formed thereon is uniformly controlled.

Abstract: A piezoelectric inkjet printhead including an upper substrate formed of a single crystal silicon substrate or an SOI substrate and having an ink inlet therethrough, and a lower substrate formed of an SOI substrate having a sequentially stacked structure with a first silicon layer, an intervening oxide layer, and a second silicon layer in which a manifold, pressure chambers, and dampers are formed in the second silicon layer by wet or dry etching, and nozzles are formed through the intervening oxide layer and the first silicon layer by dry etching, and a method of manufacturing the same.