US6259155B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymer enhanced column grid array
Assignee: GlobalFoundries Inc
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Filing: 1999-04-12
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Granted: 2001-07-10
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Expires: 2019-04-12
Abstract
Abstract A ceramic column grid array package suitable for mounting application specific integrated circuits or microprocessor chips onto a printed circuit board employing polymer reinforced columns on the substrate module is described. The polymer enhancement is formed by coating a thin conformal film of a polymer, such as, a polyimide onto the substrate module after the formation of the ceramic column grids to mechanically enhance the column to substrate attachment of the column to the substrate prior to mounting on a printed circuit card. Upon curing of the polymer film at a temperature below the melting point of the solder bond attaching the column grid to the substrate, the columns will be mechanically reinforced in their attachment to the substrate. Upon removal of the substrate module from a printed circuit card during rework, the columns of the grid array will remain with the substrate module, leaving no columns on the printed circuit card.
Inventors
- 👤 Mario John Interrante
- 👤 Raymond Alan Jackson
- 👤 Sudipta Kumar Ray
- 👤 Paul A. Zucco
- 👤 Scott R. Dwyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:59
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3431; H05K3/3436; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; H10W90/00; H10W90/701; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10954; H05K2201/10977; H05K2203/00; H05K2203/04; H05K2203/0415; H05K2203/17; H05K2203/176; H10W72/00; H10W72/851; H10W72/874; H10W72/877; H10W90/721; H10W90/724; Y; Y02; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
103 words
A package for mounting integrated circuit chips onto circuit boards comprising: a substrate having an integrated circuit chip mounted on a first side and a plurality of input/output pads on a second side; at least one wire column attached to at least one of the plurality of input/output pads, wherein the at least one wire column is formed of a solder alloy and is attached by a solder bond to the input/output pad; a polymer coating on the second side of the substrate providing a conformal coating on the solder bond; and an adhesion promoter interposed between the polymer coating and the substrate.
Claim 2
Dependent Claim
103 words
A package for mounting integrated circuit chips onto circuit boards comprising: a substrate having an integrated circuit chip mounted on a first side and a plurality of input/output pads on a second side; at least one wire column attached to at least one of the plurality of input/output pads, wherein the at least one wire column is formed of a solder alloy and is attached by a solder bond to the input/output pad; a polymer coating on the second side of the substrate providing a conformal coating on the solder bond; and an adhesion promoter interposed between the polymer coating and the substrate.
Claim 3
Dependent Claim
25 words
The package of claim 1 , wherein the at least one wire column is secured to the input/output pad using a low melting point solder.
Claim 4
Dependent Claim
22 words
The package of claim 1 , wherein the at least one wire column is formed of a high melting point solder alloy.
Claim 5
Dependent Claim
44 words
The package of claim 1 , wherein the at least one wire column is formed of a solder alloy with a melting point higher than about 270° C. and which is wettable by a solder having a melting point less than about 240° C.
Claim 6
Dependent Claim
34 words
The package of claim 1 , wherein the at least one wire column has a diameter of about 0.3 to about 0.5 mm and a height of about 1.0 mm to about 2.5 mm.
Claim 7
Dependent Claim
25 words
The package of claim 2 wherein the low melting point solder has a melting point in the range of about 180 to about 240° C.
Claim 8
Dependent Claim
44 words
The package of claim 1 , wherein the polymer coating has a thickness of about 5 to about 40 microns on the substrate and extends onto the at least one wire column to a height of between about 0.3 mm to about 1 mm.
Claim 9
Dependent Claim
21 words
The package of claim 1 wherein the polymer is a siloxane polyimide having a glass transition temperature of about 142° C.
Claim 10
Dependent Claim
21 words
The package of claim 1 wherein the polymer is Ultem 1040 (Tm) having a glass transition temperature of about 180° C.
Claim 11
Dependent Claim
19 words
The package of claim 1 wherein the adhesion promoter has a thickness of about 1 to about 2 microns.
Claim 12
Dependent Claim
15 words
The package of claim 1 wherein the adhesion promoter is a silane based coupling agent.
Claim 13
Dependent Claim
12 words
The package of claim 1 wherein the adhesion promoter is gamma aminopropyltriethoxysilane.
Claim 14
Dependent Claim
18 words
The package of claim 1 , wherein the substrate is made of ceramic material, organic material or silicon.
Claim 15
Dependent Claim
29 words
The package of claim 1 , wherein the polymer has a glass transition temperature which is less than the melting point of the solder alloy of the wire columns.
Claim 16
Dependent Claim
13 words
The package of claim 1 , wherein the polymer is a siloxane polyimide.
Claim 17
Dependent Claim
12 words
The package of claim 1 , wherein the polymer is a polyetherimide.
Claim 18
Dependent Claim
25 words
The package of claim 4 , wherein the at least one wire column is made of lead/tin solder having about 5% to about 30% tin.
Claim 19
Dependent Claim
25 words
The package of claim 4 , wherein the at least one wire column is made of lead/tin solder having about 2% to about 3% silver.
Claim 20
Dependent Claim
21 words
The package of claim 4 , wherein the at least one wire column is made of tin having about 1% germanium.
Claim 21
Dependent Claim
21 words
The package of claim 4 , wherein the at least one wire column is made of tin having about 3% copper.
Claim 22
Dependent Claim
15 words
The package of claim 6 wherein the low melting point solder is a tin/lead eutectic.
Claim 23
Dependent Claim
23 words
The package of claim 6 , wherein the low melting point solder is a tin solder having about 3% to about 5% antimony.
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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) | 2004-07-09 | 2005-01-08 | 2005-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-07-09 | 2009-01-08 | 2009-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-07-09 | 2013-01-08 | 2013-07-10 | $7700.00 | Window Closed / Lapsed |