Patent US4710977A successfully refreshed from Google Patents.
US4877482A
Expired / Lapsed
US
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Nitride removal method
Assignee: NXP USA Inc
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Filing: 1989-03-23
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Granted: 1989-10-31
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Expires: 2009-03-23
Abstract
Abstract A method for removing nitride coatings from metal tooling and mold surfaces without damaging the underlying base metal includes placing the nitride coated metal surface into a plasma reactor and subjecting it to a gaseous plasma comprising a reactive fluorine species. The reactive fluorine species may be derived from one or more of many well known gases. An optional step of cleaning the nitride coating is recommended.
Inventors
- 👤 James H. Knapp
- 👤 George F. Carney
- 👤 Francis J. Carney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:33
CPC Classifications
C; C23; C23F; C23F4/00; C23G; C23G5/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
49 words
A method for removing nitride coatings from metal surfaces comprisng the steps of: providing a metal surface having a nitride coating disposed thereon; placing said nitride coated metal surface into a plasma reactor; and exposing said nitride coated metal surface to a gaseous plasma comprising a reactive fluorine species.
Claim 2
Independent Claim
49 words
A method for removing nitride coatings from metal surfaces comprisng the steps of: providing a metal surface having a nitride coating disposed thereon; placing said nitride coated metal surface into a plasma reactor; and exposing said nitride coated metal surface to a gaseous plasma comprising a reactive fluorine species.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the providing step includes providing a metal surface having a titanium nitride coating disposed thereon.
Claim 4
Dependent Claim
19 words
The method of claim 1 further comprising the step of cleaning the nitride coating disposed on the metal surfaces.
Claim 5
Dependent Claim
44 words
The method of claim 3 wherein the cleaning step comprises the steps of: cleaning the nitride coating with acetone; cleaning said nitride coating with isopropyl alcohol; cleaning said nitride coating with methanol; and subjecting said nitride coating to a gaseous plasma consisting of oxygen.
Claim 6
Dependent Claim
47 words
The method of claim 1 wherein the exposing step includes exposing the nitride coated metal surface to a reactive fluorine species derived from one or more of the gases in the group comprising CF 4 , CHF 3 , C 2 F 6 and SF 6 .
Claim 7
Dependent Claim
63 words
The method of claim 1 wherein the placing step includes placing the nitride coated metal surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is in the range of 0.5 to 5.0 torr, the chamber temperature is in the range of 40 to 100 degrees centigrade and the power is in the range of 100 to 1000 watts.
Claim 8
Dependent Claim
48 words
The methods of claim 6 wherein the placing step includes placing the nitride coated metal surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is approximately 1.0 torr, the chamber temperature is approximately 80 degrees centigrade and the power is approximately 400 watts.
Claim 9
Independent Claim
96 words
A method for removing nitride coating from metal tooling and mold surfaces comprising the steps of: providing a metal tooling or mold surface having a nitride coating disposed thereon; cleaning said nitride coating; placing said nitride coated metal tooling or mold surface into a plasma reactor; and exposing said nitride coated metal tooling or mold surface to a gaseous plasma comprising a reactive fluorine species, said reactive fluorine species being derived from one or more of the gases in the group comprising CF 4 , CHF 3 , C 2 F 6 and SF 6 .
Claim 10
Independent Claim
96 words
A method for removing nitride coating from metal tooling and mold surfaces comprising the steps of: providing a metal tooling or mold surface having a nitride coating disposed thereon; cleaning said nitride coating; placing said nitride coated metal tooling or mold surface into a plasma reactor; and exposing said nitride coated metal tooling or mold surface to a gaseous plasma comprising a reactive fluorine species, said reactive fluorine species being derived from one or more of the gases in the group comprising CF 4 , CHF 3 , C 2 F 6 and SF 6 .
Claim 11
Dependent Claim
24 words
The method of claim 8 wherein the providing step includes providing a metal tooling or mold surface having a titanium nitride coating disposed thereon.
Claim 12
Dependent Claim
48 words
The method of claim 9 wherein the cleaning step comprises the steps of: cleaning the titanium nitride coating with acetone; cleaning said titanium nitride coating with isopropyl alcohol; cleaning said titanium nitride coating with methanol; and subjecting said titanium nitride coating to a gaseous plasma consisting of oxygen.
Claim 13
Dependent Claim
67 words
The method of claim 10 wherein the placing step includes placing the titanium nitride coated metal tooling or mold surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is in the range of 0.5 to 5.0 torr, the chamber temperature is in the range of 40 to 100 degrees centigrade and the power is in the range of 100 to 1000 watts.
Claim 14
Dependent Claim
52 words
The method of claim 11 wherein the placing step includes placing the titanium nitride coated metal tooling or mold surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is approximately 1.0 torr, the chamber temperature is approximately 80 degrees centigrade and the power is approximately 400 watts.
Claim 15
Independent Claim
139 words
A method for removing titanium nitride coatings from metal tooling or mold surfaces comprising the steps of: providing a metal tooling or mold surface having a titanium nitride coating disposed thereon; cleaning said titanium nitride coating; placing said titanium nitride coated metal tooling or mold surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is in the range of 0.5 to 5.0 torr, the chamber temperature is in the range of 40 to 100 degrees centigrade and the power is in the range of 100 to 1000 watts; and exposing said nitride coated metal tooling or mold surface to a gaseous plasma comprising a reactive fluorine species being derived from one or more of the gases in the group comprising CF 4 , CHF 3 , C 2 F 6 and SF 6 .
Claim 16
Independent Claim
139 words
A method for removing titanium nitride coatings from metal tooling or mold surfaces comprising the steps of: providing a metal tooling or mold surface having a titanium nitride coating disposed thereon; cleaning said titanium nitride coating; placing said titanium nitride coated metal tooling or mold surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is in the range of 0.5 to 5.0 torr, the chamber temperature is in the range of 40 to 100 degrees centigrade and the power is in the range of 100 to 1000 watts; and exposing said nitride coated metal tooling or mold surface to a gaseous plasma comprising a reactive fluorine species being derived from one or more of the gases in the group comprising CF 4 , CHF 3 , C 2 F 6 and SF 6 .
Claim 17
Dependent Claim
48 words
The method of claim 13 wherein the cleaning step comprises the steps of: cleaning the titanium nitride coating with acetone; cleaning said titanium nitride coating with isopropyl alcohol; cleaning said titanium nitride coating with methanol; and subjecting said titanium nitride coating to a gaseous plasma consisting of oxygen.
Claim 18
Dependent Claim
52 words
The method of claim 13 wherein the placing step includes placing a titanium nitride coated metal tooling or mold surface into a plasma reactor having a barrel configured chamber wherein the chamber pressure is approximately 1.0 torr, the chamber temperature is approximately 80 degrees centigrade and the power is approximately 400 watts.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-30 | 1993-05-01 | 1993-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-30 | 1997-05-01 | 1997-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-30 | 2001-05-01 | 2001-10-31 | $7700.00 | Window Closed / Lapsed |