US4684055A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of selectively soldering the underside of a substrate having leads
Assignee: Intersil Corp
•
Filing: 1985-09-09
•
Granted: 1987-08-04
•
Expires: 2005-09-09
Abstract
Abstract A method for soldering the underside of a substrate between leads. A paste of solder emulsified in a flux material is printed onto a carrier and film. The paste is adhered to the film by drying or reflowing before being placed onto the substrate between the projecting leads. The substrate and film are then heated. The molten solder having an affinity for plated surface areas of the substrate and no affinity for the polyimide film transfers and self-aligns to the plated surfaces of the substrate. The method allows selective soldering of the underside surface of a substrate having leads without soldering these leads, or selective soldering of some plated areas of a substrate while leaving other plated areas free of solder.
Inventors
- 👤 Scott D. Baer
- 👤 Thomas P. Glenn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:57
CPC Classifications
B; B23; B23K; B23K3/00; B23K3/06; B23K35/00; B23K35/02; B23K35/0222; H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3465; H05K3/3485; H05K2201/00; H05K2201/10; H05K2201/10227; H05K2201/10424; H05K2201/10613; H05K2201/10954; H05K2201/10984; H05K2203/00; H05K2203/01; H05K2203/0147; H05K2203/0156; H05K2203/03; H05K2203/0338
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
81 words
The method of applying solder to metallic areas of a substrate comprising: placing a solder carrier having solder paste adhered to said carrier on one surface onto a substrate surface in predetermined areas having metallic and non-metallic areas, wherein said solder paste surface of said carrier faces said substrate surface and said paste areas substantially coincide with said metallic areas; heating said solder carrier and substrate to transfer said solder to said metallic areas; and remove said carrier from said substrate.
Claim 2
Independent Claim
81 words
The method of applying solder to metallic areas of a substrate comprising: placing a solder carrier having solder paste adhered to said carrier on one surface onto a substrate surface in predetermined areas having metallic and non-metallic areas, wherein said solder paste surface of said carrier faces said substrate surface and said paste areas substantially coincide with said metallic areas; heating said solder carrier and substrate to transfer said solder to said metallic areas; and remove said carrier from said substrate.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein said solder paste is a suspension of solder in a flux material.
Claim 4
Dependent Claim
19 words
The method of claim 2, including depositing said solder paste onto said solder carrier and drying said paste thereon.
Claim 5
Dependent Claim
19 words
The method of claim 2, including depositing said solder paste onto said solder carrier and reflowing said paste thereon.
Claim 6
Dependent Claim
12 words
The method of claim 1, wherein said solder carrier is a film.
Claim 7
Dependent Claim
10 words
The method of claim 5, wherein said film is polyimide.
Claim 8
Dependent Claim
14 words
The method of claim 5, wherein said solder paste is printed onto said film.
Claim 9
Dependent Claim
19 words
The method of claim 7, wherein said solder printing matches the metallic areas to be soldered of said substrate.
Claim 10
Dependent Claim
11 words
The method of claim 1, wherein said substrate surface has leads.
Claim 11
Dependent Claim
29 words
The method of claim 9, wherein said film is placed entirely in between the leads and wherein said film has a width less than the distance between said leads.
References Cited (Backward Citations)
US3726007A
Cited
US3950200A
Cited
US4327124A
Cited
US4304640A
Cited
US4332341A
Cited
US4339784A
Cited
US4442966A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-03 | 1991-02-02 | 1991-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-03 | 1995-02-02 | 1995-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-03 | 1999-02-02 | 1999-08-04 | $7700.00 | Window Closed / Lapsed |