US5298058A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroless copper plating bath
Assignee: C Uyemura & Co Ltd
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Filing: 1992-11-30
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Granted: 1994-03-29
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Expires: 2012-11-30
Abstract
Abstract An electroless copper plating bath comprises a water soluble copper salt, a complexing agent, and a reducing agent consisting of phosphorous acid or a phosphite. As compared with conventional acidic bath using hypophosphorous acid, the bath is less expensive while depositing a uniform copper film at equivalent efficiency.
Inventors
- 👤 Fujio Matsui
- 👤 Yasuyuki Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:46
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/31; C23C18/38; C23C18/40
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
35 words
An electroless copper plating bath comprising in water a water soluble salt of copper a complexing agent, and a reducing agent consisting of a phosphorous acid or a phosphite, said bath having an acidic pH.
Claim 2
Dependent Claim
35 words
An electroless copper plating bath comprising in water a water soluble salt of copper a complexing agent, and a reducing agent consisting of a phosphorous acid or a phosphite, said bath having an acidic pH.
Claim 3
Dependent Claim
43 words
The bath of claim 1 which contains about 0.02 to abut 0.1 mol/liter of the copper salt, at least about 1 mol of the complexing agent per mol of the copper salt, and about 0.02 to about 0.2 mol/liter of the reducing agent.
Claim 4
Dependent Claim
13 words
The bath of claim 1, wherein the pH thereof is 4 to 6.4.
Claim 5
Dependent Claim
43 words
The bath of claim 3 which contains about 0.02 to about 0.1 mol/liter of the copper salt, at least about 1 mol of the complexing agent per mol of the copper salt, and about 0.02 to about 0.2 mol/liter of the reducing agent.
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) | 1997-03-28 | 1997-09-27 | 1998-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-28 | 2001-09-27 | 2002-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-28 | 2005-09-27 | 2006-03-29 | $7700.00 | Window Closed / Lapsed |