Patent US5572405A successfully refreshed from Google Patents.
US5572405A
Expired / Lapsed
US
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Thermally enhanced ball grid array package
Assignee: International Business Machines Corp
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Filing: 1995-06-07
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Granted: 1996-11-05
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Expires: 2015-06-07
Abstract
Abstract A thermally enhanced ball grid array package for electronic components, with an electronic and a plurality of ceramic component carriers bonded to a metal heat sink, enhances thermal performance, reduces solder ball fatigue and reduces stresses between the ceramic component carriers and the heat sink. Bonding the ceramic component carriers to the heat sink reduces expansion induced stresses of the solder balls on the carriers. Plural ceramic component carriers, smaller than a single carrier would have to be for the same package, reduce stresses at the interfaces between the ceramic component carriers and the heat sink.
Inventors
- 👤 James W. Wilson
- 👤 Stephen R. Engle
- 👤 Scott P. Moore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:12
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/62; H10W70/65; H10W40/00; H10W40/10; H10W40/20; H10W40/22; H10W40/25; H10W40/251; H10W90/00; H10W90/401; H10W90/701; H10W72/00; H10W72/071; H10W72/072; H10W72/07251; H10W72/20; H10W72/50; H10W72/541; H10W72/5449; H10W90/731; H10W90/736; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
99 words
A thermally enhanced electronic package comprising: a thermally conductive member having a first coefficient of thermal expansion; a first electronic component bonded to said thermally conductive member; a plurality of discreet connector members bonded to said thermally conductive member and each having: at least one coefficient of thermal expansion different from said first coefficient of thermal expansion; a plurality of fusible conductors on at least one surface; and a plurality of conductive passageways; said electronic component being electrically connected to conductive passageways in a plurality of said connector members and electrically connected through said passageways to said fusible conductors.
Claim 2
Dependent Claim
99 words
A thermally enhanced electronic package comprising: a thermally conductive member having a first coefficient of thermal expansion; a first electronic component bonded to said thermally conductive member; a plurality of discreet connector members bonded to said thermally conductive member and each having: at least one coefficient of thermal expansion different from said first coefficient of thermal expansion; a plurality of fusible conductors on at least one surface; and a plurality of conductive passageways; said electronic component being electrically connected to conductive passageways in a plurality of said connector members and electrically connected through said passageways to said fusible conductors.
Claim 3
Dependent Claim
29 words
A package according to claim 1, further comprising a second electronic component having conductive contacts on at least one surface, said fusible conductors being fused to said conductive contacts.
Claim 4
Dependent Claim
23 words
A package according to claim 2 wherein said fusible conductors comprise solder balls and said second electronic component comprises a printed circuit board.
Claim 5
Dependent Claim
16 words
A package according to claim 3 wherein said first electronic component comprises an integrated circuit chip.
Claim 6
Dependent Claim
42 words
A package according to claim 4 wherein said integrated circuit chip is connected to said conductive passageways by wire bonds, whereby said chip is electrically connected to said printed circuit board by said wire bonds, said conductive pathways and said solder balls.
Claim 7
Dependent Claim
23 words
A package according to claim 1 wherein said thermally conductive member comprises a copper heat sink, and said connector member comprises a ceramic.
Claim 8
Dependent Claim
45 words
A package according to claim 6 wherein said copper heat sink has a coefficient of thermal expansion of about 16×10 -6 to 21×10 -6 cm/cm° C. and said connector members have a coefficient of thermal expansion of about 6×10 -6 to 8×10 -6 cm/cm° C.
Claim 9
Dependent Claim
22 words
A package according to claim 7 wherein said connector members are bonded to said copper heat sink with a thermally conductive adhesive.
Claim 10
Dependent Claim
13 words
A package according to claim 8 wherein said conductive adhesive comprises an epoxy.
Claim 11
Dependent Claim
47 words
A package according to claim 1 having four of said connector members, each of said carriers having a trapezoidal shape, a first edge and a second edge, said second edge being parallel to and shorter than said first edge and positioned adjacent to said first electronic component.
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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) | 1999-11-05 | 2000-05-06 | 2000-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-11-05 | 2004-05-06 | 2004-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-11-05 | 2008-05-06 | 2008-11-05 | $7700.00 | Window Closed / Lapsed |