A bubble-jet type ink-jet printhead is provided. When forming a doughnut-shaped bubble, the printhead allows bubbles to be first grown around the heater that surrounds the central axis of the nozzle at regular angles followed by the formation of another bubble between the earlier formed bubbles, thereby forming a larger doughnut-shaped bubble. Accordingly, this can prevent the formation of an unbalanced doughnut-shaped bubble due to variations in local resistance of the heater, which may be caused by a process error. Furthermore, the printhead allows the center of the doughnut-shaped bubble to be set on the central axis of the nozzle thus causing a droplet formed within the doughnut-shaped bubble to be ejected in a normal manner, that is, in a direction vertical to the nozzle plate.

Bubble-jet type ink-jet printhead

The invention provides a method of producing a through-hole, a substrate used to produce a through-hole, a substrate having a through-hole, and a device using such a through-hole or a substrate having such a through-hole, which are characterized in that: a through-hole can be produced only by etching a silicon substrate from its back side; the opening length d can be precisely controlled to a desired value regardless of the variations in the silicon wafer thickness, and the orientation flat angle, and also regardless of the type of a silicon crystal orientation-dependent anisotropic etchant employed; high productivity, high production reproducibility, and ease of production can be achieved; a high-liberality can be achieved in the shape of the opening end even if temperature treatment is performed at a high temperature for a long time; and a high-precision through-hole can be produced regardless of the shape of a device formed on the surface of a substrate.

Method of producing a through-hole, silicon substrate having a through-hole, device using such a substrate, method of producing an ink-jet print head, and ink-jet print head

The present invention provides an ink-jet printhead substructure highly thermally efficient and greatly simplified in both the method of manufacture and resulting structure. The printhead substructure of the present invention comprises a resistor formed on an insulated substrate, a single conductive layer that provides both the conductive bonding interconnect pads and the conductive traces for the substructure, a passivation layer and a cavitation barrier. The resistor, passivation layer and cavitation barrier may comprise a single graded layer. The graded thin-film structure provides the resistor, passivation and cavitation barrier components without creating abrupt layer interfaces thereby, improving printhead reliability and durability. Fabrication of the printhead substructure of the present invention requires only two or three lithographic masks and a minimized number of sputter source materials.

Thin-film printhead device for an ink-jet printer

The invention provides a method for making ink feed vias in semiconductor silicon substrate chips for an ink jet printhead and ink jet printheads containing silicon chips made by the method. The method includes applying a first photoresist material to a first surface side of the chip. The first photoresist material is patterned and developed to define at least one ink via location therein. An etch stop material is applied to a second surface side of the chip. At least one ink via is anisotropically etched with a dry etch process through the thickness of the silicon chip up to the etch stop layer from the first surface side of the chip. As opposed to conventional ink via formation techniques, the method significantly improves the throughput of silicon chip and reduces losses due to chip breakage and cracking. The resulting chips are more reliable for long term printhead use.

Ink jet printheads and methods therefor

A manufacturing process and construction for printing heads which operate using coincident forces, drop on demand printing principles. The print head integrates many nozzles into a single monolithic silicon structure. Semiconductor processing methods such as photolithography and chemical etching are used to simultaneously fabricate a multitude of nozzles into the monolithic head. The nozzles are etched through the silicon substrate, allowing two dimensional arrays of nozzles for color printing. The manufacturing process can be based on existing CMOS, nMOS and bipolar semiconductor manufacturing processes, allowing fabrication in existing semiconductor fabrication facilities. Drive transistors, shift registers, and fault tolerance circuitry can be fabricated on the same wafer as the nozzles. The manufacturing process uses anisotropic wet etching to etch ink channels and nozzle barrels from the back surface of the wafer to the front surface of the wafer. The etching follows the crystallographic planes of the silicon, which result in highly accurate and consistent etch angles using simple etching equipment.

Monolithic print head structure and a manufacturing process therefor using anisotropic wet etching

An ink fill slot can be precisely manufactured in a substrate utilizing photolithographic techniques with chemical etching, plasma etching, or a combination thereof These methods may be used in conjunction with laser ablation, mechanical abrasion, or electromechanical machining to remove additional substrate material in desired areas The ink fill slots are appropriately configured to provide the requisite volume of ink at increasingly higher frequency of operation of the printhead by means of an extended portion that results in a reduced shelf length and thus reduced fluid impedance imparted to the ink The extended portion is precisely etched to controllably align it with other elements of the printhead

Fabrication of ink fill slots in thermal ink-jet printheads utilizing chemical micromachining

A process for manufacturing a thin film resistor substrate useful, for example, in fabricating an ink jet printhead, wherein discontinuous strips of conductive material are initially patterned on the surface of a resistive layer. These strips are formed using a first series of masking and etching steps of define an "X" dimension of a resistive heater element. Then, the conductive strips and resistive material therebetween are completely masked in preparation for a subsequent, second etching step used to remove the exposed portions of the resistive layer and thereby define a "Y" dimension of the resistive heater element. These steps leave smooth contours, good step coverage and high quality bevelled edges of the thus defined conductive and resistive layers. These layers are now ready for subsequent passivation layer, barrier layer and orifice plate deposition processes to complete a thin film printhead for use in an ink jet printer.

Thin film device for an ink jet printhead and process for manufacturing same

A printhead for an inkjet printer employs an ink fill slot having an extended portion disposed as a depression on the primary surface of the printhead substrate. The barrier layer of the printhead forms the walls of the ink ejection chambers, the walls of and constrictions in the ink fill channels, and the contoured barrier lobes between the ink fill channels. The extended portion of the ink fill slot follows the contour of the barrier lobes such that the length of the substrate shelf between the ink fill channel constriction and the extended portion of the ink fill slot is equalized between ink ejection chambers.

Inkjet printer printhead having equalized shelf length

An ink fill slot 18 can be precisely manufactured in a substrate 12 utilizing photolithographic techniques with chemical etching, plasma etching, or a combination thereof. These methods may be used in conjunction with laser ablation, mechanical abrasion, or electromechanical machining to remove additional substrate material in desired areas. The ink fill slots may be appropriately configured to provide the requisite volume of ink at increasingly higher frequency of operation of the printhead.

Jeffrey A. Kahn

Papers

Fabrication of ink fill slots in thermal ink-jet printheads utilizing chemical micromachining

Thin film device for an ink jet printhead and process for manufacturing same

Inkjet printer printhead having equalized shelf length

Method for manufacturing a thermal ink-jet print head