US5829667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for strengthening a solder joint when attaching integrated circuits to printed circuit boards
Assignee: International Business Machines Corp
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Filing: 1996-09-19
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Granted: 1998-11-03
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Expires: 2016-09-19
Abstract
Abstract A method for increasing the strength of a solder joint between a nickel-iron lead frame of an electronic circuit module and a copper pad of a printed circuit board on which the module is mounted includes baking the joint for at least one hour at a temperature in the range 373K to 456K. The baking step is found to significantly increase the strength of the joint.
Inventors
- 👤 Frank John Martin
- 👤 Brian Robertson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:12
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/19; H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3421; B23K2101/00; B23K2101/36; B23K2101/40; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10621; H05K2201/10689; H05K2201/10742; H05K2201/10886; H05K2201/10909; H05K2203/00; H05K2203/11; H05K2203/1105; Y; Y02; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
95 words
A method of producing an electronic circuit assembly comprising at least one electronic component having a nickel-iron lead frame and a printed circuit board having copper pads corresponding to leads of the lead frame, the method comprising the step of: depositing solder on the copper pads; placing the leads of the component in contact with the solder on the copper pads; and reflowing the solder to produce a solder joint between each pad and the corresponding lead, and baking the joint between one and twenty hours at a temperature in the range 373K to 456K.
Claim 2
Independent Claim
95 words
A method of producing an electronic circuit assembly comprising at least one electronic component having a nickel-iron lead frame and a printed circuit board having copper pads corresponding to leads of the lead frame, the method comprising the step of: depositing solder on the copper pads; placing the leads of the component in contact with the solder on the copper pads; and reflowing the solder to produce a solder joint between each pad and the corresponding lead, and baking the joint between one and twenty hours at a temperature in the range 373K to 456K.
Claim 3
Independent Claim
58 words
A method for increasing the strength of a solder joint between a nickel-iron lead frame of an electronic circuit module and a copper pad of a printed circuit board on which the module is mounted, the method comprising the step of baking the joint between one and twenty hours at a temperature in the range 373K to 456K.
Claim 4
Independent Claim
58 words
A method for increasing the strength of a solder joint between a nickel-iron lead frame of an electronic circuit module and a copper pad of a printed circuit board on which the module is mounted, the method comprising the step of baking the joint between one and twenty hours at a temperature in the range 373K to 456K.
Claim 5
Dependent Claim
23 words
A method as claimed in claim 2, comprising baking the joint about two hours at a temperature in the range 373K to 456K.
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) | 2001-11-02 | 2002-05-04 | 2002-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-02 | 2006-05-04 | 2006-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-02 | 2010-05-04 | 2010-11-03 | $7700.00 | Window Closed / Lapsed |