US4089709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for passivating aluminum layers on semiconductive devices
Assignee: National Semiconductor Corp
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Filing: 1977-02-28
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Granted: 1978-05-16
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Expires: 1997-02-28
Abstract
Abstract An aluminum layer such as an intraconnect on an integrated circuit semiconductive device is passivated by oxidizing the aluminum layer to form a thin layer of amorphous alumina thereon. The alumina layer is coated with a surface active agent to form a hydrophobic surface on the aluminum oxide to inhibit the creation and growth of ALOOH on the oxide layer. The hydrophobic surface is coated with a conventional passivating material such as silicon dioxide, epoxy or the like.
Inventors
- 👤 James M. Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:11
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6314; C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/07; C23C22/08; H10P95/00; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/065; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
121 words
A method for passivating an aluminum layer on a semiconductive device having a substrate containing circuit elements wherein said aluminum layer is deposited on said semiconductive device to form an interconnect pattern for said elements, said method including the steps of: oxidizing the surface of said aluminum layer to form an aluminum oxide layer thereon, said aluminum oxide layer being relatively thin with respect to the thickness of said aluminum layer; coating said aluminum oxide layer with a surface active agent to form a hydrophobic surface on said aluminum oxide to inhibit nucleation and growth of AlOOH on said aluminum oxide layer; and thereafter coating said semiconductor device with a deposited protective layer whereby a device of improved passivity is obtained.
Claim 2
Independent Claim
121 words
A method for passivating an aluminum layer on a semiconductive device having a substrate containing circuit elements wherein said aluminum layer is deposited on said semiconductive device to form an interconnect pattern for said elements, said method including the steps of: oxidizing the surface of said aluminum layer to form an aluminum oxide layer thereon, said aluminum oxide layer being relatively thin with respect to the thickness of said aluminum layer; coating said aluminum oxide layer with a surface active agent to form a hydrophobic surface on said aluminum oxide to inhibit nucleation and growth of AlOOH on said aluminum oxide layer; and thereafter coating said semiconductor device with a deposited protective layer whereby a device of improved passivity is obtained.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said surface active agent is an ion.
Claim 4
Dependent Claim
33 words
The method of claim 2 wherein said surface active ion is selected from the group consisting of, PO 4 -3 , SO 4 -2 , NO 3 -1 , and Cl -1 .
Claim 5
Dependent Claim
36 words
The method of claim 1 wherein said aluminum oxide layer is coated with said surface active agent by exposing said aluminum oxide surface to be coated to an aqueous solution on NH 4 NO 3 .
Claim 6
Dependent Claim
34 words
The method of claim 1 wherein said aluminum oxide layer is coated with said surface active agent by exposing said aluminum oxide surface to be coated to an aqueous solution of NH 4 Cl.
Claim 7
Dependent Claim
38 words
The method of claim 1 wherein said aluminum oxide layer is coated with said surface active agent by exposing said aluminum oxide surface to be coated to an aqueous solution of NH 4 H 2 PO 4 .
Claim 8
Dependent Claim
47 words
The method of claim 1 wherein said aluminum oxide layer is coated with said surface active agent by exposing said aluminum oxide surface to be coated to an aqueous solution of Al 2 (SO 4 ) 3 (NH 4 ) 2 SO 4 .sup.. 24H 2 O.
Claim 9
Dependent Claim
13 words
The method of claim 1 wherein said surface active agent is an anion.
Claim 10
Dependent Claim
23 words
The method of claim 1 wherein the surface active agent has a proton level falling within the range of -0.44 to -0.69 eV.
Claim 11
Dependent Claim
26 words
The method of claim 1 wherein the surface active agent has a radius ratio of cation to oxygenion falling within the range of 0.25 to 0.45.
Claim 12
Dependent Claim
19 words
The method of claim 1 wherein the surface active agent forms a compound on the surface of the alumina.
Claim 13
Dependent Claim
10 words
The product made according to the method of claim 1.
References Cited (Backward Citations)
US3622843A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-15 | 1981-11-14 | 1982-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-15 | 1985-11-14 | 1986-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-15 | 1989-11-14 | 1990-05-16 | $7700.00 | Window Closed / Lapsed |