Invalidity dossier
US 6951384
Ink jet heater chip and method therefor
Current assignee: Slingshot Printing LLC
Added 9/23/2026, 9:11:50 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6,951,384 B2
Title: Ink jet heater chip and method therefor
Patent number: US6951384B2
Inventors: Frank Edward Anderson; George Keith Parish
Original assignee: Lexmark International, Inc. (current assignee listed as Slingshot Printing LLC)
Application number: US10/872,925
Priority date: 2002-12-17
Filing date: 2004-06-21
Publication date (grant): 2005-10-04
Status: Expired – Lifetime
Purpose. The invention relates to ink jet heater chips and methods for producing heater chips for ink jet printers. Thermal ink jet printers use resistive heating elements to heat ink and form a vapor bubble in an ink chamber, urging ink through an orifice. Because the high pressures generated during bubble formation and collapse can damage heating elements over the life of a printhead, such chips are typically fabricated with multiple layers of passivation and protection materials on the resistive heating elements. The stated aim is an ink jet heater chip with improved thermal efficiency.
Plain-language scope. The chip comprises a semiconductor substrate; a first metal resistive layer; and a second metal conductive layer on first and second portions of the resistive layer, defining a heater resistor element between those portions. A passivation layer having a first thickness, defined by a deposition process alone, is deposited on the second metal conductive layer and the heater resistor element. A cavitation layer is deposited and etched adjacent the passivation layer over the heater resistor element and the second portion of the resistive layer. A dielectric layer having a second thickness is deposited and etched over the first portion of the resistive layer, with an electrical conduit via etched in it. A third metal conductive layer is deposited and etched adjacent the dielectric layer and in the via for electrical contact with the second metal conductive layer.
A stated advantage is independently controlling passivation and dielectric layer thicknesses to improve thermal efficiency, and controlling final passivation thickness over the heater resistor by deposition alone, avoiding passivation-thinning etch steps.
Not established by this excerpt. The claims, the full method steps, detailed layer materials/thicknesses, and omitted description text are not reproduced; verify against the source.
Generated 10/1/2026, 9:40:53 PM
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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