US4368220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passivation of RIE patterned al-based alloy films by etching to remove contaminants and surface oxide followed by oxidation
Assignee: International Business Machines Corp
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Filing: 1981-06-30
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Granted: 1983-01-11
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Expires: 2001-06-30
Abstract
Abstract Aluminum-based alloy films and metallization layers that are patterned by reactive ion etching (RIE) are passivated by etching surface portions of the films or layers with a phosphoric-chromic mixture to remove contaminants and then oxidizing the exposed surface portions in an oxygen atmosphere.
Inventors
- 👤 Jerome M. Eldridge
- 👤 Michael H. Lee
- 👤 Geraldine C. Schwartz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:24
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6314; C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/10; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/20; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
74 words
A process for passivating a reactive ion etched aluminum based metallization patterned layer, said layer having an airformed oxide portion, comprising the steps of: etching surface portions of said metallization layer with a phosphoric-chromic etchant solution to completely strip the oxide portion as well as a relatively small amount of the underlying aluminum patterned layer so as to remove substantially all contaminants; and oxidizing the exposed surface of said layer in an oxygen atmosphere.
Claim 2
Dependent Claim
74 words
A process for passivating a reactive ion etched aluminum based metallization patterned layer, said layer having an airformed oxide portion, comprising the steps of: etching surface portions of said metallization layer with a phosphoric-chromic etchant solution to completely strip the oxide portion as well as a relatively small amount of the underlying aluminum patterned layer so as to remove substantially all contaminants; and oxidizing the exposed surface of said layer in an oxygen atmosphere.
Claim 3
Dependent Claim
32 words
A process as in claim 1, wherein said mixture is formed with 50 grams CrO 3 , and 90 milliliters H 3 PO 4 in 2500 milliliters of H 2 O total.
Claim 4
Dependent Claim
22 words
A process as in claim 1, wherein said etching step is accomplished for approximately two minutes at about 55° and 80° C.
Claim 5
Dependent Claim
29 words
A process as in claim 1, wherein said oxidizing step is accomplished in an atmosphere of pure oxygen for about 30-45 minutes at a temperature of about 300°-350° C.
Claim 6
Dependent Claim
46 words
A process according to claim 1, including the further steps, following the etching step and prior to the oxidizing step, of: rinsing the etched surface portions in deionized water at room temperature and then, drying the etched portions in filtered air or nitrogen at elevated temperature.
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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) | 1986-01-10 | 1986-07-12 | 1987-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-10 | 1990-07-12 | 1991-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-10 | 1994-07-12 | 1995-01-11 | $7700.00 | Window Closed / Lapsed |