US5344795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for encapsulating an integrated circuit using a removable heatsink support block
Assignee: Microelectronics and Computer Technology Corp
•
Filing: 1992-09-22
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Granted: 1994-09-06
•
Expires: 2012-09-22
Abstract
Abstract A process for making thermosetting or thermoplastic encapsulated integrated circuit having a heat exchanger in which one end of the heat exchanger is encapsulated in the housing adjacent to the integrated circuit and the other end is exposed to the environment beyond the housing portion. The process of making includes molding a heat exchanger into a thermosetting or thermoplastic package utilizing a preformed heat exchanger having a dissolvable or removable material which serves as a seal block during the molding operation. A plurality of thermally conductive heat exchanger elements are provided for providing the desired thermal performance while reducing the thermal stresses in the package.
Inventors
- 👤 Seyed H. Hashemi
- 👤 Michael A. Olla
- 👤 Thomas P. Dolbear
- 👤 Richard D. Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:37
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/01; H10W74/016; H10W40/00; H10W40/70; H10W40/77; H10W40/778; H10W90/00; H10W90/701; H10W90/751; H10W90/754; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
181 words
A method of making an encapsulated integrated circuit chip having a heat exchanger, comprising, providing an integrated circuit structure which includes an integrated circuit chip on a substrate, the chip electrically connected to a plurality of leads extending from the substrate; preforming a removable seal and support block supporting a plurality of spaced thermally conductive heat exchanger elements having first and second ends, said support block engaging and supporting the second ends of the heat exchanger elements while leaving the first ends exposed; inserting the support block in a mold cavity such that the support block is spaced from the integrated circuit structure and the first ends of the heat exchanger elements are positioned adjacent to the integrated circuit structure; molding a non-electrically conductive thermosetting or thermoplastic material to form a housing in the mold cavity enclosing the chip and the first ends of the heat exchanger elements while allowing the second ends of the heat exchanger elements to be exposed to the exterior of the housing; and removing the support block from the second ends of the heat exchanger elements.
Claim 2
Independent Claim
181 words
A method of making an encapsulated integrated circuit chip having a heat exchanger, comprising, providing an integrated circuit structure which includes an integrated circuit chip on a substrate, the chip electrically connected to a plurality of leads extending from the substrate; preforming a removable seal and support block supporting a plurality of spaced thermally conductive heat exchanger elements having first and second ends, said support block engaging and supporting the second ends of the heat exchanger elements while leaving the first ends exposed; inserting the support block in a mold cavity such that the support block is spaced from the integrated circuit structure and the first ends of the heat exchanger elements are positioned adjacent to the integrated circuit structure; molding a non-electrically conductive thermosetting or thermoplastic material to form a housing in the mold cavity enclosing the chip and the first ends of the heat exchanger elements while allowing the second ends of the heat exchanger elements to be exposed to the exterior of the housing; and removing the support block from the second ends of the heat exchanger elements.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the support block is removed by dissolving the block in a solvent.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein the support block is selected from the group consisting of nylon, polyurethane and styrene.
Claim 5
Dependent Claim
22 words
The method of claim 1 wherein the heat exchanger elements are a plurality of spaced parallel fins with their first ends interconnected.
Claim 6
Dependent Claim
28 words
The method of claim 1 wherein the heat exchanger elements include a plurality of parallel extending and generally evenly spaced rows of pins supported by the support block.
Claim 7
Dependent Claim
20 words
The method of claim 5 wherein the first ends of the pins include an enlarged head for increased heat dissipation.
Claim 8
Dependent Claim
25 words
The method of claim 1 wherein the support is a peel-off backing Sheet-releasably secured by adhesive to the second ends of the heat exchanger elements,
Claim 9
Dependent Claim
24 words
The method of claim 1 including attaching a heat exchanger extension to the second ends of at least some of the heat exchanger elements.
Claim 10
Dependent Claim
31 words
The method of claim 1 wherein the support block seals the second ends from the thermosetting or thermoplastic material during molding and thereby prevents the material from encapsulating the second ends.
Claim 11
Dependent Claim
11 words
The method of claim 1 wherein the preforming is by pre-molding.
Claim 12
Dependent Claim
11 words
The method of claim 1 wherein the preforming is by pre-casting.
Claim 13
Dependent Claim
20 words
The method of claim 1 wherein the heat exchanger elements are selected from the group consisting of aluminum and graphite.
Claim 14
Dependent Claim
13 words
The method of claim 1 wherein the heat exchanger elements are a metal.
Claim 15
Dependent Claim
27 words
The method of claim 1 wherein the thermosetting or thermoplastic material is selected from the group consisting of epoxy, polyphenylene sulfide, polyetherimide, polyethersulfone, or liquid crystal polymers.
Claim 16
Dependent Claim
22 words
The method of claim 14 wherein the epoxy is selected from the group consisting of anhydride epoxy, novolak epoxy and polyimide epoxy.
Claim 17
Dependent Claim
14 words
The method of claim 1 wherein the thermosetting or thermoplastic material is a plastic.
Claim 18
Dependent Claim
21 words
The method of claim 1 wherein the first ends of the heat exchanger elements are positioned adjacent the integrated circuit chip.
Claim 19
Dependent Claim
27 words
The method of claim 1 wherein the first ends of the heat exchanger elements are positioned adjacent a side of the substrate opposite the integrated circuit chip.
Claim 20
Dependent Claim
21 words
The method of claim 1 wherein the first ends of the heat exchanger elements are spaced from the integrated circuit structure.
Claim 21
Dependent Claim
22 words
The method of claim 1 wherein the first ends of the heat exchanger elements are in contact with the integrated circuit structure.
Claim 22
Dependent Claim
23 words
The method of claim 1 wherein the second ends of the heat exchanger elements are inserted within the support block before molding occurs.
Claim 23
Dependent Claim
21 words
The method of claim 1 wherein the second ends of the heat exchanger elements extend from the exterior of the housing.
Claim 24
Dependent Claim
18 words
The method of claim 1 wherein the heat exchanger elements are electrically isolated from the integrated circuit chip.
Claim 25
Dependent Claim
22 words
The method of claim 1 wherein portions of the housing are disposed between the integrated circuit structure and the heat exchanger elements.
Claim 26
Dependent Claim
17 words
The method of claim 1 wherein portions of the housing are disposed between the heat exchanger elements.
Claim 27
Dependent Claim
20 words
The method of claim 1 wherein the heat exchanger elements are selected from the group consisting of aluminum and graphite.
Claim 28
Dependent Claim
13 words
The method of claim 1 wherein the heat exchanger elements are a metal.
Claim 29
Dependent Claim
20 words
The method of claim 1 wherein the heat exchanger elements are attached to the integrated circuit structure before molding occurs.
Claim 30
Dependent Claim
20 words
The method of claim 1 wherein the heat exchanger elements are not attached to the integrated structure before molding occurs.
Claim 31
Dependent Claim
21 words
The method of claim 1 wherein the heat exchanger elements are attached to the integrated circuit structure solely by the housing.
Claim 32
Dependent Claim
17 words
The method of claim 1 wherein the housing extends beyond all surfaces of the integrated circuit structure.
Claim 33
Dependent Claim
15 words
The method of claim 1 including allowing the leads to sealably extend through the housing.
References Cited (Backward Citations)
US3579056A
Cited
US3590466A
Cited
US3686533A
Cited
US3836825A
Cited
US4009752A
Cited
US4136442A
Cited
US4244098A
Cited
US4333102A
Cited
US4242157A
Cited
US4451004A
Cited
US4407006A
Cited
US4356864A
Cited
US4530152A
Cited
US4611238A
Cited
US4421161A
Cited
US4750031A
Cited
US4465130A
Cited
US4593456A
Cited
US4620216A
Cited
US4965660A
Cited
US4682208A
Cited
US4598308A
Cited
US4624302A
Cited
JPS62109326A
Cited
US5022462A
Cited
US4730666A
Cited
US4964458A
Cited
US4682651A
Cited
US4721996A
Cited
US4715430A
Cited
US4878108A
Cited
US4888449A
Cited
US4899210A
Cited
US4868349A
Cited
JPH0279451A
Cited
US5057903A
Cited
US5006924A
Cited
US4993482A
Cited
US5083194A
Cited
US5254500A
Cited
US5070936A
Cited
US5218759A
Cited
US5185654A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-09-05 | 1998-03-07 | 1998-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-05 | 2002-03-07 | 2002-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-05 | 2006-03-07 | 2006-09-06 | $7700.00 | Window Closed / Lapsed |