Patent US2864669A successfully refreshed from Google Patents.
Patent US4975146A successfully refreshed from Google Patents.
US4975146A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma removal of unwanted material
Assignee: NXP USA Inc
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Filing: 1989-09-08
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Granted: 1990-12-04
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Expires: 2009-09-08
Abstract
Abstract A method fpr removing coatings from surfaces without damaging the underlying surface includes placing a surface having material to be removed thereon into a plasma reactor and exposing it to a gaseous plasma comprising a reactive halogen species. The reactive halogen species may be derived from one or more of many well known halogen gases. An optional step of cleaning the coating prior to exposure to the halogen plasma is recommended.
Inventors
- 👤 James H. Knapp
- 👤 George F. Carney
- 👤 Francis J. Carney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:05
CPC Classifications
C; C23; C23G; C23G5/00; B; B44; B44C; B44C1/00; B44C1/22; C23F; C23F4/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
52 words
A method for removing material from surfaces comprising the steps of: providing a surface including material to be removed thereon; cleaning said material to be removed; placing said surface including said material to be removed into a plasma reactor; and exposing said surface to a gaseous plasma comprising a reactive halogen species.
Claim 2
Independent Claim
52 words
A method for removing material from surfaces comprising the steps of: providing a surface including material to be removed thereon; cleaning said material to be removed; placing said surface including said material to be removed into a plasma reactor; and exposing said surface to a gaseous plasma comprising a reactive halogen species.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein the surface is comprised of metal, plastic, glass or ceramic.
Claim 4
Dependent Claim
18 words
The method of claim 2 wherein the reactive halogen species includes one or more of fluorine and chlorine.
Claim 5
Dependent Claim
19 words
The method of claim 3 wherein the material to be removed comprises a nitride or a chromium containing material.
Claim 6
Dependent Claim
52 words
The method of claim 1 wherein the cleaning step comprises the steps of: cleaning the material to be removed with acetone; cleaning said material to be removed with isopropyl alcohol; cleaning said material to be removed with methanol; and subjecting said material to be removed to a gaseous plasma consisting of oxygen.
Claim 7
Independent Claim
65 words
A method for removing material from surfaces comprising the steps of: providing a surface comprised of metal, plastic, glass or ceramic having a material to be removed thereon; cleaning said material to be removed; placing said surface including said material to be removed into a plasma reactor; and exposing said surface to a gaseous plasma comprising one or more of reactive fluorine and chlorine species.
Claim 8
Independent Claim
65 words
A method for removing material from surfaces comprising the steps of: providing a surface comprised of metal, plastic, glass or ceramic having a material to be removed thereon; cleaning said material to be removed; placing said surface including said material to be removed into a plasma reactor; and exposing said surface to a gaseous plasma comprising one or more of reactive fluorine and chlorine species.
Claim 9
Dependent Claim
19 words
The method of claim 6 wherein the material to be removed comprises a nitride or a chromium containing material.
Claim 10
Dependent Claim
52 words
The method of claim 7 wherein the cleaning step comprises the steps of: cleaning the material to be removed with acetone; cleaning said material to be removed with isopropyl alcohol; cleaning said material to be removed with methanol; and subjecting said material to be removed to a gaseous plasma consisting of oxygen.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |