Abstract: In an ink-jet printhead and a method for manufacturing the same, the ink-jet printhead includes a substrate, an ink chamber to be filled with ink formed on a front surface of the substrate, a manifold for supplying ink to the ink chamber formed on a rear surface of the substrate, and an ink passage in flow communication with the ink chamber and the manifold formed parallel to the front surface of the substrate; a nozzle plate including a plurality of passivation layers formed of an insulating material on the front surface of the substrate, a heat dissipating layer formed of a metallic material, and a nozzle in flow communication with the ink chamber; and a heater and a conductor, the heater being positioned on the ink chamber and heating ink in the ink chamber, and the conductor for applying a current to the heater.

Abstract: A monolithic ink-jet printhead, and a method of manufacturing the same, includes a substrate having an ink chamber, an ink channel, and a manifold, a nozzle plate formed on the substrate, a nozzle, a heater, and a conductor. The ink chamber includes sidewalls formed to a predetermined depth from the front surface of the substrate for defining side surfaces of the ink chamber and a bottom wall formed parallel to the front surface of the substrate at the predetermined depth from the front surface of the substrate for defining a bottom surface of the ink chamber. The nozzle plate includes a plurality of passivation layers, a heat dissipating layer being stacked on the passivation layers, and the nozzle for ejecting ink out of the printhead. The heater is positioned above the ink chamber and heats ink in the ink chamber and the conductor delivers a current to the heater.

Abstract: A method of ejecting ink from a ink-jet printhead includes filling a rear end of a nozzle with ink using a capillary force, the rear end of the nozzle being surrounded by a hydrophilic layer, forming an electric field directed toward an outlet of the nozzle on a front end of the nozzle, the front end of the nozzle being surrounded by a hydrophobic layer, varying a surface tension of ink to separate ink droplets having a predetermined volume from ink and to move the separated ink droplets within the front end of the nozzle toward the outlet of the nozzle, and ejecting the separated ink droplets through the outlet of the nozzle.

Abstract: A method for manufacturing the same, wherein the monolithic ink-jet printhead includes a manifold for supplying ink, an ink chamber having a hemispheric shape, and an ink channel formed monolithically on a substrate; a silicon oxide layer, in which a nozzle for ejecting ink is centrally formed in the ink chamber, is deposited on the substrate; a heater having a ring shape is formed on the silicon oxide layer to surround the nozzle; a MOS integrated circuit is mounted on the substrate to drive the heater and includes a MOSFET and electrodes connected to the heater. The silicon oxide layer, the heater, and the MOS integrated circuit are formed monolithically on the substrate. Additionally, a DLC coating layer having a high hydrophobic property and high durability is formed on an external surface of the printhead.

Abstract: A method of ejecting ink from a ink-jet printhead includes filling a rear end of a nozzle with ink using a capillary force, the rear end of the nozzle being surrounded by a hydrophilic layer, forming an electric field directed toward an outlet of the nozzle on a front end of the nozzle, the front end of the nozzle being surrounded by a hydrophobic layer, varying a surface tension of ink to separate ink droplets having a predetermined volume from ink and to move the separated ink droplets within the front end of the nozzle toward the outlet of the nozzle, and ejecting the separated ink droplets through the outlet of the nozzle.

Abstract: A thermally-driven ink-jet printhead includes a substrate having an ink chamber to be filled with ink to be ejected, a manifold for supplying ink, and an ink channel for providing flow communication therebetween. First and second sidewalls are formed to a predetermined depth from an upper surface of the substrate and define the ink chamber to have a substantially rectangular shape. A nozzle plate including a plurality of material layers is formed on the substrate. A nozzle passes through the nozzle plate and is in flow communication with the ink chamber. A heater is disposed between the nozzle and one of the first sidewalls above the ink chamber. A conductor is electrically connected to the heater. The conductor and the heater are disposed within the nozzle plate. A shifting feature moves cavitation points beyond an outer edge of the heater.

Abstract: A method of driving an ink-jet printhead, which heats ink contained in an ink chamber using a heater to generate and expand a bubble within the ink chamber and ejects ink from the ink chamber using an expansive force of the bubble, the method including applying a main pulse to the heater to eject ink and applying a post pulse to the heater after ink has been ejected.

Abstract: An ink-jet printhead, and a method of manufacturing the same, includes a substrate, an ink chamber, a manifold, and an ink channel formed between the ink chamber and the manifold to provide flow communication between the ink chamber and the manifold, a substantially flat nozzle plate formed on the upper surface of the substrate, the nozzle plate including a plurality of passivation layers, a heat dissipation layer disposed on the plurality of passivation layers, the heat dissipation layer formed of a thermally conductive material and including a first thermally conductive layer formed on the plurality of passivation layers and a second thermally conductive layer formed on the first thermally conductive layer, and a nozzle extending through the nozzle plate in flow communication with the ink chamber, and a heater and a conductor, the heater heating ink filled in the ink chamber and the conductor applying current to the heater.

Abstract: A monolithic ink-jet printhead, and a method of manufacturing the same, includes a substrate having an ink chamber, an ink channel, and a manifold, a nozzle plate formed on the substrate, a nozzle, a heater, and a conductor. The ink chamber includes sidewalls formed to a predetermined depth from the front surface of the substrate for defining side surfaces of the ink chamber and a bottom wall formed parallel to the front surface of the substrate at the predetermined depth from the front surface of the substrate for defining a bottom surface of the ink chamber. The nozzle plate includes a plurality of passivation layers, a heat dissipating layer being stacked on the passivation layers, and the nozzle for ejecting ink out of the printhead. The heater is positioned above the ink chamber and heats ink in the ink chamber and the conductor delivers a current to the heater.

Abstract: An apparatus and method for driving an ink-jet printhead in which current is applied to a heater to heat ink to be supplied in an ink chamber to generate a bubble to eject ink from the ink chamber, the apparatus including a circuit that alternately applies current to the heater to alternate a direction of current flowing through the heater.

Abstract: A method of expelling a fluid includes filling a nozzle with a fluid using a capillary force, generating an ion wind by ionizing air near an outlet of the nozzle, and expelling the fluid from the nozzle as the ion wind decreases a pressure around the outlet of the nozzle. An ink-jet printhead utilizing the method includes a manifold formed in a passageway plate to supply ink, a nozzle to be supplied with ink formed in a nozzle plate provided on the passageway plate, and a ground electrode and a source electrode arranged near an outlet of the nozzle, the ground electrode and the source electrode forming an electric field due to an application of a voltage thereto and ionizing air near the outlet of the nozzle to produce an ion wind to decrease a pressure near the outlet of the nozzle to expel the ink contained in the nozzle.

Abstract: A thermally-driven ink-jet printhead includes a substrate having an ink chamber to be filled with ink to be ejected, a manifold for supplying ink, and an ink channel for providing flow communication therebetween. First and second sidewalls are formed to a predetermined depth from an upper surface of the substrate and define the ink chamber to have a substantially rectangular shape. A nozzle plate including a plurality of material layers is formed on the substrate. A nozzle passes through the nozzle plate and is in flow communication with the ink chamber. A heater is disposed between the nozzle and one of the first sidewalls above the ink chamber. A conductor is electrically connected to the heater. The conductor and the heater are disposed within the nozzle plate. A shifting feature moves cavitation points beyond an outer edge of the heater.

Abstract: An ink-jet printhead includes a substrate having an ink chamber and a manifold, a nozzle plate formed on the substrate, first and second heaters and conductors, a material layer, and a plurality of ink channels. The nozzle plate includes a plurality of passivation layers formed of an insulating material, a heat dissipation layer formed on the plurality of passivation layers and made of a thermally conductive material, and a nozzle passing through the nozzle plate and in flow communication with the ink chamber. The first and second heaters and conductors are interposed between adjacent passivation layers of the nozzle plate. The material layer is interposed between the ink chamber and the manifold to form a bottom wall of the ink chamber and a top wall of the manifold. The plurality of ink channels is formed in the material layer to provide flow communication between the ink chamber and the manifold.

Abstract: An apparatus for controlling a temperature of an ink-jet printhead includes a heater driving field effect transistor (FET) connected to a heater, the heater driving FET for applying a heater voltage to the heater according to a waveform input to a gate of the heater driving FET, a current sensor for converting current flowing between a drain and a source of the heater driving FET into a voltage and for outputting the voltage, a comparator for comparing the voltage output from the current sensor with a predetermined reference voltage, a warming control signal generator for generating a warming control signal in a form of a pulse string, and a switching unit for receiving an output signal from the comparator and the warming control signal, and for outputting the warming control signal according to a level of the output signal from the comparator to the gate of the heater driving FET.

Abstract: A monolithic ink-jet printhead, and a method of manufacturing the same, includes a substrate having an ink chamber, an ink channel, and a manifold, a nozzle plate formed on the substrate, a nozzle, a heater, and a conductor. The ink chamber includes sidewalls formed to a predetermined depth from the front surface of the substrate for defining side surfaces of the ink chamber and a bottom wall formed parallel to the front surface of the substrate at the predetermined depth from the front surface of the substrate for defining a bottom surface of the ink chamber. The nozzle plate includes a plurality of passivation layers, a heat dissipating layer being stacked on the passivation layers, and the nozzle for ejecting ink out of the printhead. The heater is positioned above the ink chamber and heats ink in the ink chamber and the conductor delivers a current to the heater.

Abstract: A monolithic ink-jet printhead includes a substrate having an ink chamber, a manifold, and an ink channel in flow communication, a nozzle plate including a plurality of passivation layers stacked on the substrate and a heat dissipating layer stacked on the passivation layers, a nozzle for ejecting ink penetrating the nozzle plate, a heater provided between adjacent passivation layers above the ink chamber, and a conductor between adjacent passivation layers, the conductor being electrically connected to the heater, wherein the heat dissipating layer is made of a thermally conductive metal for dissipating heat from the heater, the lower part of the nozzle is formed by penetrating the plurality of passivation layers, and the upper part of the nozzle is formed by penetrating the heat dissipating layer in a tapered shape in which a cross-sectional area thereof decreases gradually toward an exit thereof.

Abstract: An ink-jet printhead includes a substrate having an ink chamber and a manifold, a nozzle plate formed on the substrate, first and second heaters, first and second conductors, and first and second ink channels. The nozzle plate includes a plurality of passivation layers formed of an insulating material, a heat dissipation layer formed on the passivation layers and made of a thermally conductive material, and a nozzle passing through the nozzle plate and in flow communication with the ink chamber. The first and second heaters and conductors are interposed between adjacent passivation layers of the nozzle plate. The ink channels are interposed between the ink chamber and the manifold, for providing flow communication between the ink chamber and the manifold. The first and second heaters, conductors and ink channels are symmetric with respect to the nozzle.

Abstract: A monolithic ink-jet printhead includes a substrate which has an ink chamber to be supplied with ink, a manifold for supplying ink to the ink chamber, and an ink channel for providing communication between the ink chamber and the manifold, a nozzle plate including a plurality of passivation layers sequentially stacked on the substrate, a metal layer formed on the passivation layers, and a nozzle, through which ink is ejected from the ink chamber, that penetrates the nozzle plate, a heater provided between adjacent passivation layers, the heater being located above the ink chamber for heating ink within the ink chamber, a conductor provided between adjacent passivation layers, the conductor being electrically connected to the heater for applying a current to the heater, and a hydrophobic coating layer formed exclusively on an outer surface of the metal layer.

Abstract: A monolithic ink-jet printhead includes a substrate having an ink chamber to be supplied with ink to be ejected on a front surface thereof, a manifold for supplying ink to the ink chamber on a rear surface thereof, and an ink channel in communication with the ink chamber and the manifold, a nozzle plate including a plurality of passivation layers stacked on the substrate and a heat dissipating layer overlying the passivation layers, the nozzle plate having a nozzle penetrating the nozzle plate, a heater formed between adjacent passivation layers and located above the ink chamber for heating the ink to be supplied within the ink chamber, and a conductor provided between adjacent passivation layers, the conductor being electrically connected to the heater for applying current across the heater, wherein the heat dissipating layer is made of a thermally conductive metal for dissipating heat from the heater.

Abstract: A polymerase chain reaction apparatus includes: a substrate; a high-temperature sidewall erected on the substrate; a low-temperature sidewall erected on the substrate and facing the high-temperature sidewall; and a reaction chamber consisting of the substrate, the high-temperature sidewall, and the low-temperature sidewall, wherein a sample contained in the reaction chamber is repetitively thermal-circulated between the high-temperature sidewall and the low-temperature sidewall using Marangoni convection generated by a surface tension gradient resulting from a temperature difference in an interface between the sample and air. The PCR amplification can be automatically accomplished by surface tension flow generated by Marangoni convection resulting from a temperature difference in an interface between the sample and air when a temperature difference between the sidewalls of the chamber is maintained constant.