US4170472A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solder system
Assignee: Motorola Solutions Inc
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Filing: 1977-04-19
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Granted: 1979-10-09
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Expires: 1997-04-19
Abstract
Abstract A solder system for metallurgically bonding a semiconductor die to a metal package member. The solder is based on the tin rich corner of the tin-antimony-silver ternary alloy system. The solder system has particular applicability to the bonding of power transistors.
Inventors
- 👤 Dennis R. Olsen
- 👤 Keith G. Spanjer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:08
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/26; B23K35/262
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
56 words
A solder composition for metallurgically bonding a metal backed semiconductor die to a metal package member, said solder composition compatible with and capable of wetting the metal backing of said metal backed semiconductor die, said composition comprising 61 to 69 weight percent tin, 8 to 11 weight percent antimony and 23 to 28 weight percent silver.
Claim 2
Dependent Claim
56 words
A solder composition for metallurgically bonding a metal backed semiconductor die to a metal package member, said solder composition compatible with and capable of wetting the metal backing of said metal backed semiconductor die, said composition comprising 61 to 69 weight percent tin, 8 to 11 weight percent antimony and 23 to 28 weight percent silver.
Claim 3
Dependent Claim
21 words
The solder composition of claim 1 consisting of 65 weight percent tin, 10 weight percent antimony and 25 weight percent silver.
Claim 4
Dependent Claim
66 words
In a process for metallurgically bonding a metal backed semiconductor die to a metal package member by placing solder between said die and said member and heating to cause said solder to melt and wet said die and said member, the improvement of using a solder comprising 61 to 69 weight percent tin, 8 to 11 weight percent antimony and 23 to 28 weight percent silver.
Claim 5
Dependent Claim
66 words
In a process for metallurgically bonding a metal backed semiconductor die to a metal package member by placing solder between said die and said member and heating to cause said solder to melt and wet said die and said member, the improvement of using a solder comprising 61 to 69 weight percent tin, 8 to 11 weight percent antimony and 23 to 28 weight percent silver.
Claim 6
Dependent Claim
23 words
The process of claim 3 wherein said solder consists of 65 weight percent tin, 10 weight percent antimony and 25 weight percent silver.
References Cited (Backward Citations)
US2210593A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-10-08 | 1983-04-09 | 1983-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-08 | 1987-04-09 | 1987-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-08 | 1991-04-09 | 1991-10-09 | $7700.00 | Window Closed / Lapsed |