Xerox Corporation

David J Collins

Ram S Narang

Robert P Altavela

Stephen F Pond

Herman A Hermanson

Daniel E Kuhman

Lawrence H Herko

Robert A Harold, Sr

Kevin A Lindamood

Julie A Sims

An improved back cut method is provided in a dicing procedure for separating a plurality of printheads formed in a silicon wafer. The wafer has alignment fiducial marks formed within a composite wafer. Infrared light is directed into the wafer and is reflected back through the wafer from the fiducial marks. The reflected light is detected by a CCD camera mounted on a dicing saw. The fiducial coordinates are stored in memory and displayed so that the dicing saw can be aligned with regard to the alignment marks. A back cut operation is enabled so that the saw partially cuts through the composite wafer. A subsequent dicing step separates individual printheads from the wafer.

Method of back cutting silicon wafers during a dicing procedure

An apparatus and method for bonding wafer pairs. The apparatus includes a heated platen surrounded by a pressurization vessel. The heated platen includes channels connected to a hole which runs through the heated platen. Wafer pairs are placed on the top surface of the platen, a rubber mat is placed over the top of the wafer pairs, and a vacuum is drawn through the hole and the channels. The rubber mat compresses the wafer pairs. The platen is heated for the bonding process. The pressurization chamber is pressurized supplying additional bonding pressure to the wafer pair. Once sufficiently heated, the heated platen is liquid cooled completing the bonding process.

Apparatus for bonding wafer pairs

A plurality of ink jet printheads are produced from two aligned and bonded substrates by an improved fabrication method. The confronting surface of one of the substrates contains a plurality of linear arrays of heating elements and driver circuitry, and the confronting surface of the other substrate contains a plurality of sets of shallow channel recesses, reservoir recesses, and alignment openings. Prior to mating of the substrates, the substrate surface having the channel recesses is coated with a layer of thermosetting adhesive, and a thick film layer is deposited on the substrate surface having the heating elements and driver circuitry and patterned to provide a plurality of vias therein at predetermined locations. The vias expose the heating elements, provide ink bypass trenches, and provide a number of groupings of small pits. In one embodiment, the alignment openings are used to visually align and mate the substrates, so that each alignment opening is aligned with a respective one of the groups of small pits in the thick film layer. To prevent misalignment between the substrates before the adhesive layer is cured, a UV curable adhesive is inserted into the alignment openings and into each group of small pits in the thick film layer aligned therewith and cured, thus fastening the substrates together. The fastened substrates are placed in a curing oven without lost of alignment therebetween and the thermosetting adhesive is cured. The bonded substrates are then diced into a plurality of individual printheads.

Method of fabricating ink jet printheads

A coating for a front face of printhead in a thermal ink jet printer enables the directionality of an ink jet to be maintained for the printing lifetime of the printer. The coating controls the wetting characteristics of the front face to prevent ink accumulation on the front face. The coating comprises an epoxy adhesive resin such as EPON 1001F doped with a silicone rubber compound such as RTV 732. The coating can be provided in the form of a 24% solution of EPON 1001F in a 30:70 mixture of xylene and methyl iso-butyl ketone by weight doped with 1% by weight of RTV 732. An adhesion promoter such as an aminosilane can be included in the coating to increase bond strength between the coating and printhead front face.

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Fairport, NY, United States of America

David J Collins