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US4513298A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermal ink jet printhead

Assignee: HP Inc
•
Filing: 1983-05-25
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Granted: 1985-04-23
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Expires: 2003-05-25
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Abstract

Abstract A protective passivation structure is provided for a thermal ink jet printing head which employs a resistive heating element formed of phosphorus-diffused silicon. The passivation structure includes a layer of silicon nitride over the heating element with a layer of silicon carbide over the silicon nitride layer. The nitride exhibits good adhesion to the underlying silicon as well as good thermal conductivity. The carbide has exceptionally good wear and hardness qualities against ink bubble cavitation as well as adhering well to the nitride.

Inventors

  • 👤 Friedrich Scheu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 06:31
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/14; B41J2/14016; B41J2/14088; B41J2/14112; B41J2/14129; B41J2002/14387; B41J2202/00; B41J2202/01; B41J2202/03

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 83 words
In a thermal ink jet printhead assembly comprising a print head support member, an orifice plate having an orifice therein, means for supporting said orifice plate on said support member, and heating means formed of phosphorus diffused silicon disposed between said orifice plate and said support member and adjacent said orifice, the improvement comprising: a layer of a nitride of silicon disposed at least on said heating means, and a layer of silicon carbide disposed on said layer of said nitride of silicon.
Claim 2
Dependent Claim 83 words
In a thermal ink jet printhead assembly comprising a print head support member, an orifice plate having an orifice therein, means for supporting said orifice plate on said support member, and heating means formed of phosphorus diffused silicon disposed between said orifice plate and said support member and adjacent said orifice, the improvement comprising: a layer of a nitride of silicon disposed at least on said heating means, and a layer of silicon carbide disposed on said layer of said nitride of silicon.
Claim 3
Dependent Claim 121 words
A thermal ink jet printhead comprising: a substrate member of silicon, a thermally insulating layer of silicon dioxide on said substrate member, resistive means formed of phosphorusdiffused silicon disposed on said thermally insulating layer, electrical connection members disposed on said thermally insulating layer and in electrical contact with said resistive heating means, a layer of a nitride of silicon disposed at least on said heating means, a layer of silicon carbide disposed on said layer of said nitride of silicon, barrier members mounted on said layer of silicon carbide and adjacent at least two sides of said heating means, an orifice plate mounted on said barrier members and having an orifice therein disposed adjacent to and aligned with said heating means.
Claim 4
Dependent Claim 121 words
A thermal ink jet printhead comprising: a substrate member of silicon, a thermally insulating layer of silicon dioxide on said substrate member, resistive means formed of phosphorusdiffused silicon disposed on said thermally insulating layer, electrical connection members disposed on said thermally insulating layer and in electrical contact with said resistive heating means, a layer of a nitride of silicon disposed at least on said heating means, a layer of silicon carbide disposed on said layer of said nitride of silicon, barrier members mounted on said layer of silicon carbide and adjacent at least two sides of said heating means, an orifice plate mounted on said barrier members and having an orifice therein disposed adjacent to and aligned with said heating means.
Claim 5
Dependent Claim 16 words
The invention according to claim 2 wherein said resistive heating means is formed of polycrystalline silicon.

References Cited (Backward Citations)

US4335389A Cited
US4429321A Cited
US4438191A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-04-22 1988-10-22 1989-04-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-04-22 1992-10-22 1993-04-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-04-22 1996-10-22 1997-04-23 $7700.00 Window Closed / Lapsed

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