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Patent US4486511A successfully refreshed from Google Patents.
US4486511A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solder composition for thin coatings
Assignee: National Semiconductor Corp
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Filing: 1983-06-27
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Granted: 1984-12-04
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Expires: 2003-06-27
Abstract
Abstract A solder composition of 10 to 40 percent tin, with the balance lead, for use in thin layers of 50 to 500 microinches on copper integrated circuit leads so as to resist the formation of intermetallics when later heated.
Inventors
- 👤 Yung-Shih Chen
- 👤 Jagdish G. Belani
- 👤 Vijay Sajja
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:04
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/26; B23K35/268; H; H10; H10W; H10W72/00; H10W72/20; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12528; Y10T428/12687
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
53 words
A solder composition for use on integrated circuit lead containing a base metal which can form intermetallic compositions with the solder, the solder composition consisting of ten to forty percent (10-40%) tin with the remainder being lead, so as to avoid serious degradation of the solderability characteristic thereof due to the formed intermetallics.
Claim 2
Dependent Claim
53 words
A solder composition for use on integrated circuit lead containing a base metal which can form intermetallic compositions with the solder, the solder composition consisting of ten to forty percent (10-40%) tin with the remainder being lead, so as to avoid serious degradation of the solderability characteristic thereof due to the formed intermetallics.
Claim 3
Dependent Claim
24 words
The composition of claim 1 in which the range of tin is held between twenty-five and thirty-five percent (25-35%) with the remainder being lead.
Claim 4
Dependent Claim
19 words
The composition of claim 1 in which the solder is between fifty and five hundred (50-500) microinches in thickness.
Claim 5
Dependent Claim
24 words
An integrated circuit device having pre-plated leads coated with a solder composition consisting of ten to forty percent (10-40%) tin with the remainder lead.
Claim 6
Dependent Claim
24 words
An integrated circuit device having pre-plated leads coated with a solder composition consisting of ten to forty percent (10-40%) tin with the remainder lead.
Claim 7
Dependent Claim
23 words
The device of claim 4 in which the solder composition consists of twenty-five to thirty-five percent (25-35%) tin with the remainder being lead.
References Cited (Backward Citations)
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Cited
US3729820A
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US3761309A
Cited
US3735208A
Cited
US4097266A
Cited
JPS52130433A
Cited
US4273859A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-04 | 1988-06-04 | 1988-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-04 | 1992-06-04 | 1992-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-04 | 1996-06-04 | 1996-12-04 | $7700.00 | Window Closed / Lapsed |