Abstract: A method of printing at a dot density exceeding a nozzle density in a stationary pagewidth printhead. The method includes the steps of: (i) advancing a print medium transversely past the stationary printhead at a rate of one line per one line-time; and (ii) firing droplets of ink from predetermined nozzles in a nozzle row to create successive lines of print. Some or all of the predetermined nozzles fire droplets of ink at a plurality of predetermined different dot positions along a longitudinal axis of the printhead during one line-time, such that the printed dot density in each line of print exceeds the nozzle density.

Abstract: A method of controlling a direction of droplet ejection from an inkjet nozzle having a plurality of moveable paddles, the method includes the steps of: (i) actuating a first thermal bend actuator via respective first drive circuitry such that a respective first paddle bends towards a floor of the nozzle chamber; (ii) actuating a second thermal bend actuator via respective second drive circuitry such that a respective second paddle bends towards a floor of the nozzle chamber; and (iii) thereby ejecting a droplet of ink. Actuation of the first and second thermal bend actuators is independently controlled via the first and second drive circuitry so as to control the direction of droplet ejection.

Abstract: An inkjet printhead integrated circuit (IC) includes: a substrate having a drive circuitry layer; a plurality of nozzle assemblies disposed on an upper surface of the substrate and arranged in one or more nozzle rows extending longitudinally along the printhead IC; a nozzle plate extending across the printhead IC; and a conductive track fused to the nozzle plate which extends longitudinally along the printhead IC and parallel with the nozzle rows. The conductive track is connected to a common reference plane in the drive circuitry layer via a plurality of conductor posts extending between the drive circuitry layer and the conductive track.

Abstract: A stationary pagewidth inkjet printhead has one or more nozzle rows extending along a longitudinal axis of the printhead. Each nozzle is configurable to fire a droplet of ink at a plurality of predetermined different dot positions along the longitudinal axis, and each nozzle has an associated primary dot position. The printhead is configured to compensate for a dead nozzle by printing from a selected functioning nozzle positioned in a same nozzle row as the dead nozzle. The selected functioning nozzle is configured to fire some ink droplets at the primary dot position associated with the dead nozzle and to fire some ink droplets at its own primary dot position.

Abstract: A printhead integrated circuit (IC) for a stationary pagewidth printhead, includes nozzle rows extending along a longitudinal axis thereof. A length of a printable zone corresponding to the nozzle row is longer than a length of the nozzle row.

Abstract: A stationary pagewidth inkjet printhead has one or more nozzle rows extending along a longitudinal axis of the printhead. Each nozzle is configured to fire a droplet of ink at a plurality of predetermined different dot positions along the longitudinal axis, such that a printed dot density exceeds a nozzle density of the printhead.

Abstract: An inkjet nozzle assembly having: a nozzle chamber for containing ink, the nozzle chamber including a floor and a roof having a nozzle opening defined therein; and a plurality of moveable paddles defining part of the roof. The plurality of paddles are actuable to cause ejection of an ink droplet from the nozzle opening. Each paddle includes a thermal bend actuator, and each actuator is independently controllable via respective drive circuitry such that a direction of droplet ejection from the nozzle opening is controllable by independent movement of each paddle.

Abstract: A thermal bend actuator includes: an active beam for connection to drive circuitry; and a passive beam mechanically cooperating with the active beam, such that when a current is passed through the active beam, the active beam expands relative to the passive beam, resulting in bending of the actuator. The passive beam has first and second layers with the second layer sandwiched between the first layer and the active beam. The first layer is thicker than the second layer.

Abstract: This invention relates to a micro-electromechanical nozzle arrangement for an inkjet printhead. The arrangement includes a substrate defining an inverted pyramidal ink chamber with a vertex thereof terminating at an ink supply channel through the substrate. The substrate includes a layer of drive circuitry. The arrangement also includes a roof structure connected to the drive circuitry layer and covering the ink chamber, the roof structure defining a fluid ejection nozzle rim above said chamber. Also included is a plurality of actuators radially spaced about, and displaceable with respect to, the nozzle rim, each actuator having a serpentine heater element configured to thermally expand upon receiving current from the drive circuitry thereby moving said actuators into the chamber and operatively increasing a fluid pressure inside the chamber to eject a drop of ink via the ejection nozzle.

Abstract: A method of fabricating a printhead integrated circuit configured for backside electrical connections. The method comprises the steps of: (a) providing a wafer comprising a plurality of partially-fabricated nozzle assemblies on a frontside of the wafer and through-silicon connectors extending from the frontside towards a backside of the wafer; (b) depositing a conductive layer on the frontside of said wafer and etching to form an actuator for each nozzle assembly and a frontside contact pad over a head of each through-silicon connector; (c) performing further MEMS processing steps to complete formation of nozzle assemblies ink supply channels through-silicon connectors; and (d) dividing the wafer into individual printhead integrated circuits. Each printhead integrated circuit thus formed is configured for backside-connection to the drive circuitry via the through-silicon connectors the contact pads.

Abstract: A nozzle assembly for an inkjet printhead. The nozzle assembly includes: a nozzle chamber including a roof having a nozzle opening and a moving portion movable relative to a stationary portion of the roof. An actuator is configured to displace the moving portion relative to the stationary portion and cause ejection of ink through the nozzle opening. A polymeric coating covers the moving portion and the stationary portion. The polymeric coating is absent from a gap between the moving portion and the stationary portion.

Abstract: A microfluidic diaphragm valve. The valve comprises: an inlet port; an outlet port; a weir positioned between the inlet and outlet ports, the weir having a sealing surface; a diaphragm membrane for sealing engagement with the sealing surface; and a thermal bend actuator for moving the diaphragm membrane between a closed position in which the membrane is sealingly engaged with the sealing surface and an open position in which the membrane is disengaged from said sealing surface.

Abstract: An ink jet printhead includes a plurality of nozzles each having a nozzle aperture; a plurality of bubble forming chambers, each corresponding respectively to one of the plurality of nozzles; an inlet for communicating printing fluid between the nozzle aperture and a printing fluid supply, the inlet and the nozzle aperture being aligned along a common central axis; and a heater element disposed in each of the bubble forming chambers. Each heater element has two bubble nucleation regions suspended within the bubble forming chamber in a plane parallel to that of the nozzle aperture. The two bubble nucleation regions are laterally offset from the central axis, such that the lateral offset of one of the bubble nucleation regions is equal and opposite to the lateral offset of the other bubble nucleation region. The bubble nucleation regions are spaced from each other such that bubbles nucleated at each will grow until they unite to form the gas bubble that causes the ejection of a drop of ejectable liquid.

Abstract: A thermal bend actuator comprises an active beam for connection to drive circuitry and a passive beam mechanically cooperating with the active beam. When a current is passed through the active beam, the active beam expands relative to the passive beam resulting in bending of the actuator. The passive beam comprises a first layer comprised of silicon nitride and a second layer comprised of silicon dioxide. The second layer is sandwiched between the first layer and the active beam to provide thermal insulation for the first layer.

Abstract: A peristaltic microfluidic pump. The pump comprises a pumping chamber positioned between an inlet and an outlet; a plurality of moveable fingers positioned in a wall of the pumping chamber, the fingers being arranged in a row along the wall; and a plurality of thermal bend actuators. Each actuator is associated with a respective finger such that actuation of the thermal bend actuator causes movement of the respective finger into the pumping chamber. The pump is configured to provide a peristaltic pumping action in the pumping chamber via movement of the fingers.

Abstract: An inkjet printhead includes: a nozzle plate having a plurality of nozzle apertures and ink supply conduits for supplying ink to the nozzle apertures. Each of the ink supply conduits has a conduit wall defined by part of the nozzle plate. Each of the conduit walls includes a plurality of pressure-dampening structures for dampening pressure fluctuations experienced at the nozzle apertures.

Abstract: A MEMS integrated circuit comprising a peristaltic microfluidic pump and control circuitry for the pump. The pump comprises a pumping chamber positioned between an inlet and an outlet; a plurality of moveable fingers positioned in a wall of the pumping chamber, the fingers being arranged in a row along the wall; and a plurality of thermal bend actuators. Each actuator is associated with a respective finger such that actuation of the thermal bend actuator causes movement of the respective finger into the pumping chamber. The control circuitry controls actuation of the plurality of actuators. The control circuitry is configured to provide a peristaltic pumping action in each pumping chamber via peristaltic movement of the fingers.

Abstract: An inkjet printhead that has an elongate chassis, first groups of apertures spaced along the elongate chassis, an ink distribution unit defining a plurality of ink distribution passages and second groups of apertures in fluid communication with respective ink distribution passages, the ink distribution unit being mounted to the elongate chassis so that the first group of apertures and the second group of apertures coincide and, a plurality of printhead modules for ejecting ink supplied through the ink distribution passages and the aligned first and second groups.

Abstract: A method of providing a printhead assembly having a hydrophilic ink pathway and a hydrophobic ink ejection face. The method includes the steps of: providing a printhead assembly comprising a printhead attached to an ink supply manifold, the printhead comprising a nozzle plate having a hydrophobic coating and a protective metal film disposed on the hydrophobic coating; treating surfaces of an ink pathway in the printhead assembly with a solution comprising an alkoxylated polyethyleneimine; drying the surfaces; and removing the protective metal film so as to reveal the hydrophobic coating.

Abstract: A method of hydrophobizing a frontside surface of an integrated circuit. The method includes the steps of: (a) depositing a hydrophobic polymeric layer onto the frontside surface; (b) depositing a protective metal film onto the hydrophobic polymeric layer; (c) depositing a sacrificial material onto the metal film; (d) patterning the sacrificial material; (e) etching through the metal film, the hydrophobic polymeric layer and the frontside surface; (f) performing MEMS processing steps on a backside of the integrated circuit; (g) subjecting the integrated circuit to an oxidizing plasma, wherein the metal film protects the hydrophobic polymeric layer from the oxidizing plasma; and (h) removing the protective metal film to provide an integrated circuit having a relatively hydrophobic patterned frontside surface.