Patent US5672548A successfully refreshed from Google Patents.
US5672548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for attaching heat sinks directly to chip carrier modules using flexible-epoxy
Assignee: GlobalFoundries Inc
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Filing: 1996-06-26
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Granted: 1997-09-30
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Expires: 2016-06-26
Abstract
Abstract An aluminum or copper heat sink is attached to a ceramic cap or exposed semiconductor chip using flexible-epoxy to provide improved thermal performance. The aluminum may be coated by anodizing or chromate conversion or the copper may be coated with nickel. Such structures are especilly useful for CQFP, CBGA, CCGA, CPGA, TBGA, PBGA, DCAM, MCM-L, single layer ceramic, and other chip carrier packages as well as for flip chip attachment to flexible or rigid organic circuit boards. These adhesive materials withstand thermal cycle tests of 0° to 100° C. for 1,500 cycles, -25° to 125° C. for 400 cycles, and -40° to 140° C. for 300 cycles; and withstand continuous exposure at 130° C. for 1000 hours without loss of strength. Flexible-epoxies have a modulus of elasticity below 100,000 psi and a glass transition temperature below 25° C., are much stronger than typical silicone adhesives, and do not contaminate the module or circuit board with silicone. The flexible epoxy may contain a material having a low coefficient of thermal expansion (CTE) in order to provide a CTE between that of the silicon die and the metal of the heat sink.
Inventors
- 👤 Thomas Moran Culnane
- 👤 Michael Anthony Gaynes
- 👤 Ping Kwong Seto
- 👤 Hussain Shaukatullah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:05
CPC Classifications
H; H10; H10W; H10W40/00; H10W40/10; H10W40/20; H10W40/22; H10W40/25; H10W40/251; H10W40/70; H10W74/00; H10W74/01; H10W74/012; H10W74/10; H10W74/111; H10W74/114; H10W74/117; H10W74/15; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W70/685; H10W72/00; H10W72/851; H10W72/853; H10W72/856; H10W72/874; H10W72/877; H10W72/884; H10W90/00; H10W90/701; H10W90/721; H10W90/724; H10W90/731; H10W90/734; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
54 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 2
Independent Claim
54 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 3
Dependent Claim
40 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 25° C. and a Young's modulus of less than 100,000 psi at 25° C.
Claim 4
Dependent Claim
28 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 10° C.
Claim 5
Dependent Claim
29 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing an epoxy with a glass transition temperature of less than 0° C.
Claim 6
Dependent Claim
30 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a Young's modulus of less than 50,000 psi at 25° C.
Claim 7
Dependent Claim
30 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a Young's modules of less than 20,000 psi at 25° C.
Claim 8
Dependent Claim
29 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with material properties or formulation similar to AI Technology EG 7655.
Claim 9
Dependent Claim
29 words
The method of claim 1 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with material properties or formulation similar to ABLEBOND PI - 8971.
Claim 10
Independent Claim
61 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and an aluminum surface of a metal heat spreader; pressing the heat spreader and the chip together; and heating the module to cure the flexible-epoxy.
Claim 11
Independent Claim
61 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and an aluminum surface of a metal heat spreader; pressing the heat spreader and the chip together; and heating the module to cure the flexible-epoxy.
Claim 12
Dependent Claim
19 words
The method of claim 9 further comprising the step of anodizing the aluminum surface of the metal heat spreader.
Claim 13
Independent Claim
91 words
A method for producing a flip chip package, comprising: positioning a semiconductor flip chip on a surface of a substrate with an area array of electrical connectors extending from a first, confronting surface of the chip to a matching area array of connectors on the substrate; heating to mechanically and electrically interconnect the chip to the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the chip and a heat spreader; pressing the heat spreader and the chip together; and heating the package to cure the flexible-epoxy.
Claim 14
Independent Claim
91 words
A method for producing a flip chip package, comprising: positioning a semiconductor flip chip on a surface of a substrate with an area array of electrical connectors extending from a first, confronting surface of the chip to a matching area array of connectors on the substrate; heating to mechanically and electrically interconnect the chip to the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the chip and a heat spreader; pressing the heat spreader and the chip together; and heating the package to cure the flexible-epoxy.
Claim 15
Dependent Claim
15 words
The method of claim 11 further comprising the step of selecting a metal heat spreader.
Claim 16
Dependent Claim
59 words
The method of claim 11 further comprising the step of forming a flexible substrate of one or more patterned metal film layers supported by one or more dielectric film layers that separate adjacent metal film layers of said patterned metal film layers by alternately depositing said dielectric film layers and said patterned metal film layers on an initial layer.
Claim 17
Dependent Claim
40 words
The method of claim 11 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 25° C. and a Young's modulus of less than 100,000 psi at 25° C.
Claim 18
Independent Claim
94 words
A method for producing an interconnect structure, comprising: electrically connecting a first surface of a semiconductor chip to a first substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; elevating the temperature of the module to cure the flexible-epoxy; positioning a second surface of the first substrate in parallel contact with a surface of a second, larger substrate; and connecting together electrical connectors of the first substrate and second substrate to form an interconnect structure.
Claim 19
Independent Claim
94 words
A method for producing an interconnect structure, comprising: electrically connecting a first surface of a semiconductor chip to a first substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; elevating the temperature of the module to cure the flexible-epoxy; positioning a second surface of the first substrate in parallel contact with a surface of a second, larger substrate; and connecting together electrical connectors of the first substrate and second substrate to form an interconnect structure.
Claim 20
Dependent Claim
40 words
The method of claim 15 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 25° C.; and a Young's modulus of less than 100,000 psi at 25° C.
Claim 21
Independent Claim
81 words
A method for producing an interconnect structure, comprising: mounting a semiconductor chip in a fixed position on a first side of a first substrate; depositing flexible-epoxy which is not fully cured between a heat spreader and a surface on a second side of the first substrate; pressing the heat spreader and the second side of the first substrate together; heating the module to cure the flexible-epoxy; electrically interconnecting between metal contacts on the chip and metal contacts on a second substrate.
Claim 22
Independent Claim
81 words
A method for producing an interconnect structure, comprising: mounting a semiconductor chip in a fixed position on a first side of a first substrate; depositing flexible-epoxy which is not fully cured between a heat spreader and a surface on a second side of the first substrate; pressing the heat spreader and the second side of the first substrate together; heating the module to cure the flexible-epoxy; electrically interconnecting between metal contacts on the chip and metal contacts on a second substrate.
Claim 23
Dependent Claim
18 words
The method of claim 17 further comprising the step of selecting a ceramic material for the first substrate.
Claim 24
Dependent Claim
40 words
The method of claim 17 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 25° C.; and a Young's modulus of less than 100,000 psi at 25° C.
Claim 25
Independent Claim
129 words
A method for producing an information handling system, comprising: electrically connecting a first surface of a semiconductor chip of a central processing unit to a first substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; elevating the temperature of the module to cure the flexible-epoxy; positioning a second surface of the first substrate in parallel contact with a surface of a second, larger substrate; connecting between means for electrical and mechanical connection of the first substrate and confronting means for electrical and mechanical connection of the second substrate to form an interconnect structure; connecting the interconnect structure with power supply means, and input/output means to form an information handling system.
Claim 26
Independent Claim
129 words
A method for producing an information handling system, comprising: electrically connecting a first surface of a semiconductor chip of a central processing unit to a first substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; elevating the temperature of the module to cure the flexible-epoxy; positioning a second surface of the first substrate in parallel contact with a surface of a second, larger substrate; connecting between means for electrical and mechanical connection of the first substrate and confronting means for electrical and mechanical connection of the second substrate to form an interconnect structure; connecting the interconnect structure with power supply means, and input/output means to form an information handling system.
Claim 27
Dependent Claim
40 words
The method of claim 20 in which the step of depositing flexible-epoxy includes the step of depositing flexible-epoxy with a glass transition temperature of less than 25° C.; and a Young's modulus of less than 100,000 psi at 25° C.
Claim 28
Dependent Claim
19 words
The method of claim 1 further including the step of selecting aluminum for a surface of the heat spreader.
Claim 29
Dependent Claim
29 words
The method of claim 1 in which the heat spreader includes aluminum and further including the step of anodizing to form an anodized aluminum surface of the heat spreader.
Claim 30
Dependent Claim
32 words
The method of claim 1 in which the heat spreader includes aluminum and further including the step of forming on an aluminum surface of the heat spreader, a coating of chromate conversion.
Claim 31
Dependent Claim
13 words
The method of claim 1, further including providing copper for the heat spreader.
Claim 32
Dependent Claim
20 words
The method of claim 25 further including the step of covering copper with Ni to form the heat spreader surface.
Claim 33
Independent Claim
74 words
A method for producing a chip carrier module, comprising: connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a surface of a heat spreader; pressing the heat spreader and the chip together; depositing another epoxy to surfaces not occupied by said flexible epoxy between the heat spreader and the substrate; and heating to cure the flexible-epoxy.
Claim 34
Independent Claim
74 words
A method for producing a chip carrier module, comprising: connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a surface of a heat spreader; pressing the heat spreader and the chip together; depositing another epoxy to surfaces not occupied by said flexible epoxy between the heat spreader and the substrate; and heating to cure the flexible-epoxy.
Claim 35
Independent Claim
61 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a surface of a heat spreader of metal including copper; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 36
Independent Claim
61 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a surface of a heat spreader of metal including copper; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 37
Independent Claim
68 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a top wiring layer of a substrate; attaching J-type leads to the edge of the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 38
Independent Claim
68 words
A method for producing a chip carrier module, comprising: electrically connecting a first surface of a semiconductor chip to a top wiring layer of a substrate; attaching J-type leads to the edge of the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 39
Independent Claim
193 words
A method for producing a chip carrier module, comprising: electrically connecting a first major surface of a semiconductor chip to pads on a surface of a substrate; encapsulating a space between the first surface of the chip and the surface of the substrate, around the electrical connections with a first epoxy; depositing a conformal coating of a second epoxy which is not fully cured, on the surface of the substrate around the chip; the second epoxy coating having a thickness approximately equal to the encapsulated space plus a thickness of the chip between the first surface of the chip and a second major surface of the chip; curing the first epoxy and said conformal coating of said second epoxy; depositing flexible-epoxy which is not fully cured, between the second surface of the semiconductor chip and a surface of a heat spreader; depositing a third epoxy which is not fully cured in a volume between the area of the surface of the heat spreader extending beyond the second surface of the chip, and the conformal coating of said second epoxy; pressing the heat spreader and the substrate together; and heating to cure the flexible-epoxy.
Claim 40
Independent Claim
193 words
A method for producing a chip carrier module, comprising: electrically connecting a first major surface of a semiconductor chip to pads on a surface of a substrate; encapsulating a space between the first surface of the chip and the surface of the substrate, around the electrical connections with a first epoxy; depositing a conformal coating of a second epoxy which is not fully cured, on the surface of the substrate around the chip; the second epoxy coating having a thickness approximately equal to the encapsulated space plus a thickness of the chip between the first surface of the chip and a second major surface of the chip; curing the first epoxy and said conformal coating of said second epoxy; depositing flexible-epoxy which is not fully cured, between the second surface of the semiconductor chip and a surface of a heat spreader; depositing a third epoxy which is not fully cured in a volume between the area of the surface of the heat spreader extending beyond the second surface of the chip, and the conformal coating of said second epoxy; pressing the heat spreader and the substrate together; and heating to cure the flexible-epoxy.
Claim 41
Independent Claim
136 words
A method for producing a chip carrier module, comprising: producing, by successive deposition, a substrate having two major sides with wiring layers including an exterior wiring layer extending on each of said respective major sides of the substrate and which said exterior wiring layers include connection pads on said major sides, and with conductive vias extending between the two major sides of the substrate; and in at least one of the wiring layers, elongate conductors extending in a plane defined by a wiring layer; electrically connecting a first surface of a semiconductor chip to the connection pads on one side of the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 42
Independent Claim
136 words
A method for producing a chip carrier module, comprising: producing, by successive deposition, a substrate having two major sides with wiring layers including an exterior wiring layer extending on each of said respective major sides of the substrate and which said exterior wiring layers include connection pads on said major sides, and with conductive vias extending between the two major sides of the substrate; and in at least one of the wiring layers, elongate conductors extending in a plane defined by a wiring layer; electrically connecting a first surface of a semiconductor chip to the connection pads on one side of the substrate; depositing flexible-epoxy which is not fully cured, between a second surface of the semiconductor chip and a heat spreader; pressing the heat spreader and the chip together; and heating to cure the flexible-epoxy.
Claim 43
Dependent Claim
28 words
The method of claim 28 further comprising the step of coating the copper with a nickel cover layer to form the surface prior to attachment to the chip.
Claim 44
Dependent Claim
32 words
The method for claim 31 further comprising the step of connecting an array of solder balls to connection pads on the opposite side of the substrate from the connection of the chip.
Claim 45
Dependent Claim
29 words
The method of claim 31 further comprising the step of forming solder bumps on connection pads on the opposite side of the substrate from the connection of the chip.
Claim 46
Dependent Claim
37 words
The method of claim 31 further comprising the step of inserting pins into the substrate to form the conductive vias and which extend out from the side of the substrate opposite from the connection of the chip.
Claim 47
Dependent Claim
44 words
The method of claim 30 further comprising the step of depositing epoxy which is not fully cured in a volume between most of the area of the surface of the heat spreader extending beyond the second surface of the chip, and the conformal coating.
References Cited (Backward Citations)
US3458925A
Cited
US4000509A
Cited
US4092697A
Cited
US4604644A
Cited
US4701482A
Cited
US4825284A
Cited
US4742024A
Cited
US5159535A
Cited
US4878108A
Cited
JPS6429158A
Cited
JPH01217951A
Cited
US5097318A
Cited
US5168430A
Cited
US4914551A
Cited
JPH02136865A
Cited
JPH0312955A
Cited
US5041902A
Cited
US5121190A
Cited
US5147084A
Cited
US5455457A
Cited
US5291064A
Cited
US5375320A
Cited
US5251100A
Cited
US5198693A
Cited
US5262927A
Cited
EP0566872A2
Cited
US5367196A
Cited
US5461257A
Cited
JP3012955U
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-09-29 | 2001-03-31 | 2001-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-09-29 | 2005-03-31 | 2005-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-09-29 | 2009-03-31 | 2009-09-30 | $7700.00 | Window Closed / Lapsed |