US5641990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laminated solder column
Assignee: Intel Corp
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Filing: 1995-08-07
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Granted: 1997-06-24
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Expires: 2015-08-07
Abstract
Abstract A method for forming solder balls and an apparatus and method for forming solder columns on the electrical contact pads of an electronic package in order to establish a more reliable electrical and mechanical connection between an electronic package and a printed circuit board. In one embodiment, solder balls are formed on the electrical contact pads of a package by placing solder cylinders over the electrical contact pads and then passing the package through a reflow furnace where the solder cylinders take the form of spheres and are wetted onto the pads. In a second embodiment, a laminated solder column is formed that is resistant to collapse during the manufacturing process. The laminated solder column comprises a solder cylinder being clad on its top and bottom surfaces with a solder material having a lower melting temperature than that of the center solder cylinder. When attaching the solder column to a package or a printed circuit board reflow temperatures are maintained above the melting temperature of the cladding material but below the melting temperature of the center solder cylinder such that the cladding is wetted onto the electrical contact pads of the package or printed circuit board while the center solder cylinder maintains its solid form.
Inventors
- 👤 George W. Chiu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:57
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3431; H05K3/3436; B; B23; B23K; B23K35/00; B23K35/001; H10; H10W; H10W70/00; H10W70/099; H10W72/00; H10W72/01; H10W72/012; B23K35/22; B23K35/24; B23K35/26; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10954; H05K2201/10992; H05K2203/00; H05K2203/04; H05K2203/0415; H05K2203/043; H05K2203/0435; H10W72/20; H10W72/221; H10W72/222; H10W72/251; H10W72/252; Y; Y02; Y02P; Y02P70/00; Y02P70/50; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
83 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a laminated solder column being attached to each of said electrical contact pads, said laminated solder column having a first and second solder layer, said second solder layer being coupled to one of said electrical contact pads and having a melting temperature below the melting temperature of said first solder layer, said second solder layer being thinner than said first solder layer.
Claim 2
Dependent Claim
83 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a laminated solder column being attached to each of said electrical contact pads, said laminated solder column having a first and second solder layer, said second solder layer being coupled to one of said electrical contact pads and having a melting temperature below the melting temperature of said first solder layer, said second solder layer being thinner than said first solder layer.
Claim 3
Dependent Claim
19 words
The electronic package of claim 1 wherein said second solder layer of said laminated solder column comprises 60/40 Sn/Pb.
Claim 4
Dependent Claim
19 words
The electronic package of claim 1 wherein said first solder layer of said laminated solder column comprises 90/10 Pb/Sn.
Claim 5
Dependent Claim
121 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a laminated solder column being attached to each of said electrical contact pads, said laminated solder column having a first, second, and third solder layer and a first and second barrier layer, said first barrier layer being disposed between said first and second solder layers and said second barrier layer being disposed between said second and third solder layers, said first and third solder layers having a melting temperature below the melting temperature of said second solder layer, each of said first and third solder layers having a thickness that is less than the thickness of said second solder layer.
Claim 6
Dependent Claim
121 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a laminated solder column being attached to each of said electrical contact pads, said laminated solder column having a first, second, and third solder layer and a first and second barrier layer, said first barrier layer being disposed between said first and second solder layers and said second barrier layer being disposed between said second and third solder layers, said first and third solder layers having a melting temperature below the melting temperature of said second solder layer, each of said first and third solder layers having a thickness that is less than the thickness of said second solder layer.
Claim 7
Dependent Claim
21 words
The electronic package of claim 4 wherein said first and third solder layers of said laminated solder column comprise 60/40 Sn/Pb.
Claim 8
Dependent Claim
19 words
The electronic package of claim 4 wherein said second solder layer of said laminated solder column comprises 90/10 Pb/Sn.
Claim 9
Dependent Claim
15 words
The electronic package of claim 4 wherein said first and second barrier layers comprise nickel.
Claim 10
Dependent Claim
15 words
The electronic package of claim 4 wherein said first and second barrier layers comprise palladium.
Claim 11
Dependent Claim
136 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a plurality of laminated solder columns, each of said laminated solder columns having a first, second, and third solder layer and a first and second barrier layer, said first barrier layer being disposed between said first and second solder layers and said second barrier layer being disposed between said second and third solder layers, said first and third solder layers having a melting temperature below the melting temperature of said second solder layer, said third solder layer of each of said laminated solder columns being attached to each of said electrical contact pads, each of said first and third solder layers having a thickness that is less than the thickness of said second solder layer.
Claim 12
Dependent Claim
136 words
An electronic package comprising: a substrate having a first surface; a plurality of electrical contact pads disposed about said first surface; a plurality of laminated solder columns, each of said laminated solder columns having a first, second, and third solder layer and a first and second barrier layer, said first barrier layer being disposed between said first and second solder layers and said second barrier layer being disposed between said second and third solder layers, said first and third solder layers having a melting temperature below the melting temperature of said second solder layer, said third solder layer of each of said laminated solder columns being attached to each of said electrical contact pads, each of said first and third solder layers having a thickness that is less than the thickness of said second solder layer.
Claim 13
Dependent Claim
21 words
The electronic package of claim 9 wherein said first and third solder layers of said laminated solder column comprise 60/40 Sn/Pb.
Claim 14
Dependent Claim
19 words
The electronic package of claim 9 wherein said second solder layer of said laminated solder column comprises 90/10 Pb/Sn.
Claim 15
Dependent Claim
17 words
The electronic package of claim 9 wherein said first, second, and third solder layers comprise solder cylinders.
Claim 16
Dependent Claim
18 words
The electronic package of claim 9 wherein said first, second, and third solder layers comprise rectangular solder members.
Claim 17
Dependent Claim
15 words
The electronic package of claim 9 wherein said first and second barrier layers comprise nickel.
Claim 18
Dependent Claim
15 words
The electronic package of claim 9 wherein said first and second barrier layers comprise palladium.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-06-23 | 2000-12-23 | 2001-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-23 | 2004-12-23 | 2005-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-23 | 2008-12-23 | 2009-06-24 | $7700.00 | Window Closed / Lapsed |