Patent US5586010A successfully refreshed from Google Patents.
US5586010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low stress ball grid array package
Assignee: Hopkins Manufacturing Corp
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Filing: 1995-03-13
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Granted: 1996-12-17
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Expires: 2015-03-13
Abstract
Abstract The ball grid array package (10) uses a flexible base (30) having a substantially flat center plate (34) disposed at a first level coupled to a substantially flat base plate (32) disposed at a second level. The center plate (34) is coupled to the base plate (32) by a plurality of flexible narrow straps (36-38) arranged substantially surrounding the center plate (34). The flexible base (30) accommodates the thermal expansion in the pedestal (18) caused by the powered up integrated circuit (16) so that the rest of the package does not expand and induce stress in the solder joint between the ball grid array (12) and the printed circuit board (14).
Inventors
- 👤 Masood Murtuza
- 👤 Abbas I. Attarwala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:41
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W40/00; H10W40/20; H10W40/22; H10W40/25; H10W40/258; H10W74/00; H10W90/00; H10W90/701; H10W90/751; H10W90/754; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49147; Y10T29/49149
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
75 words
A ball grid array package for an integrated circuit, comprising: a flexible base having a center dome portion and a base portion coupled together by a plurality of straps; a metal pedestal attached to said integrated circuit and further coupled to said center dome portion of said flexible base; a substrate coupled to said base portion of said flexible base; and a plurality of solder balls formed in a grid and coupled to said substrate.
Claim 2
Dependent Claim
75 words
A ball grid array package for an integrated circuit, comprising: a flexible base having a center dome portion and a base portion coupled together by a plurality of straps; a metal pedestal attached to said integrated circuit and further coupled to said center dome portion of said flexible base; a substrate coupled to said base portion of said flexible base; and a plurality of solder balls formed in a grid and coupled to said substrate.
Claim 3
Dependent Claim
24 words
The ball grid array package, as set forth in claim 1, wherein said integrated circuit is electrically coupled to said plurality of solder balls.
Claim 4
Dependent Claim
20 words
The ball grid array package, as set forth in claim 1, wherein said flexible base is constructed from a metal.
Claim 5
Dependent Claim
22 words
The ball grid array package, as set forth in claim 1, wherein said flexible base is constructed from a good heat conductor.
Claim 6
Dependent Claim
43 words
The ball grid array package, as set forth in claim 1, wherein said flexible base is constructed from a material having a coefficient of thermal expansion similar to that of a printed circuit board upon which the ball grid array package is soldered.
Claim 7
Dependent Claim
35 words
The ball grid array package, as set forth in claim 1, wherein said flexible base is constructed from an integral piece of material having a plurality of openings formed therein to define said straps therebetween.
Claim 8
Dependent Claim
90 words
A ball grid array package having an integrated circuit electrically coupled to a substrate and a plurality of solder balls in a grid formation coupled to said substrate, the package comprising: a flexible base having a substantially flat center plate disposed at a first level, a substantially flat base plate disposed at a second level, and a plurality of windows being arranged substantially around said center portion; and a pedestal coupled to said substantially flat center plate of said flexible base, said pedestal being further coupled to said integrated circuit.
Claim 9
Dependent Claim
90 words
A ball grid array package having an integrated circuit electrically coupled to a substrate and a plurality of solder balls in a grid formation coupled to said substrate, the package comprising: a flexible base having a substantially flat center plate disposed at a first level, a substantially flat base plate disposed at a second level, and a plurality of windows being arranged substantially around said center portion; and a pedestal coupled to said substantially flat center plate of said flexible base, said pedestal being further coupled to said integrated circuit.
Claim 10
Dependent Claim
28 words
The ball grid array package, as set forth in claim 7, wherein said windows define a plurality of narrow straps connecting said center plate and said base plate.
Claim 11
Dependent Claim
19 words
The ball grid array package, as set forth in claim 7, wherein said flexible base is constructed from metal.
Claim 12
Dependent Claim
22 words
The ball grid array package, as set forth in claim 7, wherein said flexible base is constructed from a good heat conductor.
Claim 13
Dependent Claim
43 words
The ball grid array package, as set forth in claim 7, wherein said flexible base is constructed from a material having a coefficient of thermal expansion similar to that of a printed circuit board upon which the ball grid array package is soldered.
Claim 14
Dependent Claim
35 words
The ball grid array package, as set forth in claim 7, wherein said flexible base is constructed from an integral piece of material having a plurality of openings formed therein to define said straps therebetween.
Claim 15
Independent Claim
66 words
A method for decreasing solder joint stress on a ball grid array soldered to a circuit board, comprising the steps of: coupling an integrated circuit die to a center dome portion of an expandable base, said center dome portion being coupled to a base portion by a plurality of flexible narrow straps; and forming said ball grid array on said base portion of said expandable base.
Claim 16
Independent Claim
66 words
A method for decreasing solder joint stress on a ball grid array soldered to a circuit board, comprising the steps of: coupling an integrated circuit die to a center dome portion of an expandable base, said center dome portion being coupled to a base portion by a plurality of flexible narrow straps; and forming said ball grid array on said base portion of said expandable base.
Claim 17
Dependent Claim
40 words
The method, as set forth in claim 13, wherein said integrated circuit coupling step further comprises the steps of: coupling said integrated circuit die to a pedestal; and coupling said pedestal to said center dome portion of said expandable base.
Claim 18
Dependent Claim
40 words
The method, as set forth in claim 13, wherein said ball grid array forming step further comprises the steps of: coupling said base portion of said expandable base to a substrate; and forming said ball grid array on said substrate.
Claim 19
Dependent Claim
59 words
The method, as set forth in claim 13, further comprising the steps of: forming a thin plate of metal having predetermined width and length; punching out a predetermined number of openings arranged around a center portion of said thin plate and thereby defining a predetermined number of narrow metal straps; and elevating said center portion of said thin plate.
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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) | 1999-12-17 | 2000-06-17 | 2000-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-17 | 2004-06-17 | 2004-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-17 | 2008-06-17 | 2008-12-17 | $7700.00 | Window Closed / Lapsed |