U.S. patent application number 09/876508 was filed with the patent office on 2002-12-26 for thermal enhanced extended surface tape for integrated circuit heat dissipation.
This patent application is currently assigned to International Business Machines Corporation. Invention is credited to Corti, William D., Long, David C., Marsh, Joseph O., Scanzano, Franics X., Won, Michael, Yuan, Tsorng-Dih.
Application Number | 20020195228 09/876508 |
Document ID | / |
Family ID | 25367884 |
Filed Date | 2002-12-26 |
United States Patent
Application |
20020195228 |
Kind Code |
A1 |
Corti, William D. ; et
al. |
December 26, 2002 |
Thermal enhanced extended surface tape for integrated circuit heat
dissipation
Abstract
A thermal conductive tape article is provided which is adhered
to the surface of an integrated circuit device to dissipate heat
from the device. The thermal conductive tape article is preferably
corrugated and may have a number of configurations providing an
expanded surface area. The corrugated tape article may also have a
metal strip bonded to one or both sides of the tape article to form
a single-faced or double-faced corrugated tape article. The tape
article is preferably made of copper or aluminum.
Inventors: |
Corti, William D.; (New
Windsor, NY) ; Long, David C.; (Wappingers Falls,
NY) ; Marsh, Joseph O.; (Poughkeepsie, NY) ;
Scanzano, Franics X.; (Newburgh, NY) ; Won,
Michael; (Highland, NY) ; Yuan, Tsorng-Dih;
(Hopewell Junction, NY) |
Correspondence
Address: |
DELIO & PETERSON, LLC
121 WHITNEY AVENUE
NEW HAVEN
CT
06510
US
|
Assignee: |
International Business Machines
Corporation
Armonk
NY
|
Family ID: |
25367884 |
Appl. No.: |
09/876508 |
Filed: |
June 7, 2001 |
Current U.S.
Class: |
165/80.3 ;
257/E23.103 |
Current CPC
Class: |
H01L 2224/16 20130101;
H01L 2924/00014 20130101; H01L 2924/00014 20130101; H01L 23/3672
20130101; H01L 2224/73253 20130101; H01L 2224/0401 20130101 |
Class at
Publication: |
165/80.3 |
International
Class: |
F28F 007/00 |
Claims
Thus, having described the invention, what is claimed is:
1. A method to enhance integrated circuit device heat dissipation
comprising the steps of: providing an integrated circuit device
having a surface; providing a flexible strip of a thermal
conductive material; and adhering the strip to the surface of the
integrated circuit device.
2. The method of claim 1 wherein the strip is corrugated.
3. The method of claim 2 wherein the strip is metal and is copper
or aluminum.
4. The method of claim 3 wherein the thickness of the strip is 0.5
mil to 10 mil.
5. The method of claim 4 wherein the corrugated strip has
corrugations in the shape of a repeating series of triangles.
6. The method of claim 4 wherein the corrugations in the strip are
in the shape of a repeating series of convex and concave portions
comprising sidewall portions, top portions and bottom portions.
7. The method of claim 4 wherein the corrugations in the strip are
in the shape of a repeating series of convex portions comprising
angled sidewalls and a top portion and a triangular concave
portion.
8. The method of claim 4 wherein the corrugations in the strip are
in the shape of a series of vertical fins.
9. The method of claim 4 wherein the corrugating in the strip are
in the shape of a repeating series of loops.
10. The method of claim 1 wherein the flexible corrugated strips
have an adhesive thereon to adhere the corrugated strip to the
integrated circuit device.
11. The method of claim 2 wherein the flexible corrugated strip has
a flat flexible strip of a thermal conductive material bonded to
one side thereto forming a single-faced flexible corrugated strip
article.
12. The method of claim 11 wherein the flat flexible strip article
has an adhesive thereon on the side to be adhered to an integrated
circuit device.
13. The method of claim 11 wherein the single-faced flexible
corrugated strip article has a flat flexible strip of thermal
conductive material bonded to the other side of the flexible
corrugated strip forming a double-faced flexible corrugated
strip.
14. The method of claim 13 wherein at least one of the flat
flexible strips has an adhesive on the side to be adhered to the
integrated circuit device.
15. The method of claim 14 wherein each side of the flat flexible
strips has an adhesive thereon for adhering to an integrated
circuit device.
16. A method to enhance integrated circuit device heat dissipation
comprising the steps of: providing an integrated circuit device
having a surface; providing a strip of flexible flat thermal
conductive material; forming corrugations in the flexible thermal
conductive material; and adhering the corrugated flexible thermal
conductive material to the surface of an integrated circuit
device.
17. The method of claim 16 wherein an adhesive is applied to the
strip surface before corrugation.
18. The method of claim 16 wherein an adhesive is applied to a
strip surface after corrugation.
19. The method of claim 16 wherein a flexible strip thermal
conductive material is bonded to the corrugated flexible thermal
conductive material forming a single-faced corrugated strip
article.
20. The method of claim 19 wherein an adhesive is applied to the
side of a single-faced corrugated strip to be adhered to an
integrated circuit device.
21. The method of claim 19 wherein a second flexible strip thermal
conductive material is bonded to the other side of the corrugated
flexible thermal conductive material forming a double-faced
corrugated strip article.
22. The method of claim 21 wherein an adhesive is applied to the
side of the double-faced corrugated strip to be adhered to an
integrated circuit device.
23. The method of claim 22 wherein an adhesive is applied to each
side of the double-faced corrugated tape article.
24. An article of manufacture for dissipating heat for integrated
circuit devices comprising a flexible strip of thermal conductive
material having an adhesive on a portion thereof which will contact
with and adhere the strip to an integrated circuit device.
25. The article of claim 24 wherein the flexible strip is
corrugated.
26. The article of claim 25 wherein the flexible corrugated strip
has a flat flexible strip of thermal conductive material bonded to
the strip forming a single-faced flexible corrugated strip
article.
27. The article of claim 26 wherein the flat strip of thermal
conductive material has an adhesive on the side to be adhered to an
integrated circuit device.
28. The article of claim 26 wherein a second flat flexible strip of
thermal conductive material is bonded to the other side of the
corrugated tape to form a double-faced flexible corrugated
strip.
29. The article of claim 28 wherein each side of the flat flexible
strip of thermal conductive material has an adhesive thereon.
30. The article of claim 24 which has been surface treated to
increase the emmisivity of the article.
31. The article of claim 25 which has been surface treated to
increase the emmissivity of the article.
32. An electronic component assembly comprising a housing
containing an electronic component which is cooled by adhering the
flexible article of claim 24 to the electronic component and the
housing.
33. The electronic component assembly of claim 32 wherein the
housing is metal or has a thin metal coating thereon.
34. The electronic component assembly of claim 32 wherein the
flexible article used is the article of claim 25.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to dissipating heat from electronic
components and, more particularly, to a thermal conductive tape
having an extended surface area which is applied to the surface of
an integrated circuit for heat dissipation.
[0003] 2. Description of Related Art
[0004] As the need for power (heat) dissipation of electronic
components such as integrated circuits (IC) and particularly lower
power applications of less than 10 watts continues to increase, it
is of great commercial interest to enhance packaging thermal
characteristics. Existing methods are generally expensive and
require improvement in addressing the unit cost issues. For
convenience, the following description will be directed to
semiconductors (IC's), however, it will be appreciated by those
skilled in the art that the invention can be used for any type
electronic component.
[0005] Traditional methods to enhance packaging thermal
characteristics include using heat spreaders or heat sinks on the
integrated circuit component or on the package surface. Such
methods are expensive and the mechanical properties required at the
interface between the heat spreader and the package or IC surface
such as adhesion are very important and much material development
time and resources are spent on this thereby increasing the cost of
the IC device.
[0006] Traditional heat dissipation methods as shown in FIGS. 7A
and 7B use heat spreaders and/or heat sinks which are usually made
of thick pieces of aluminum or copper.
[0007] Packages with an embedded heat sink or heat slug are other
options. Other options are a cavity down plastic ball grid array
with a copper heat spreader or Power PQ2 plastic quad flat pack
with an embedded heat slug. These options typically are expensive
and such a cost increase in the package becomes prohibitive.
[0008] For example, standard plastic packages such as plastic quad
flat pack (PQFP) or plastic ball grid array (PBGA) are limited in
power dissipation to between 1-3 watt for a unit 23 mm square in
size. This has limited its acceptance for packaging consideration
in many application opportunities such as portable computers and
hand held communications devices. In order to address the
increasing power requirements, more expensive packages are needed
which reduces the cost performance competitiveness of the
package.
[0009] Bearing in mind the problems and deficiencies of the prior
art, it is therefore an object of the present invention to provide
a method to enhance electronic component heat dissipation,
especially integrated circuit electronic components.
[0010] It is another object of the present invention to provide a
thermal conductive article which is applied to electronic
components such as integrated circuits for the dissipation of heat
from the component.
[0011] A further object of the invention is to provide a method to
enhance heat dissipation for electronic components including
integrated circuit devices wherein a thermally conductive article
is formed and continuously applied to the surface of the electronic
component.
[0012] Still other objects and advantages will in part be obvious
and will in part be apparent from the specification.
SUMMARY OF THE INVENTION
[0013] The above and other objects and advantages, which will be
apparent to one of skill in the art, are achieved in the present
invention which is directed to, in a first aspect, a method to
enhance integrated circuit device heat dissipation comprising the
steps of:
[0014] providing an integrated circuit device having a surface;
[0015] providing a flexible strip of thermal conductive material
preferably corrugated (expanded surface area) and preferably having
a thermal conductive adhesive on at least one side thereof; and
[0016] adhering the strip to the surface of the integrated circuit
device.
[0017] In another aspect of the invention the strip of thermal
conductive material is a metal such as copper or aluminum having a
thickness of about 0.0005 inch to 0.010 inch (0.5 mil to 10 mil),
which has preferably been corrugated to provide an expanded surface
area up to 500% more or above the surface area of the original
strip.
[0018] In a further aspect of the invention any form of corrugation
may be formed in the thermal conductive material strip to increase
the surface area of the strip and preferred corrugation includes a
repeating series of triangles, a repeating series of convex and
concave portions comprising opposed vertical sidewall portions, and
connecting horizontal top and bottom portions, a repeating series
of convex portions comprising angled sidewalls and a connecting
horizontal top portion and a connecting triangular concave portion,
a repeating series of vertical fins and a repeating series of
loops.
[0019] In yet another aspect of the invention the flexible thermal
conductor material strip may be adhered to the integrated circuit
to be cooled by employing adhesive on the strip.
[0020] A preferred corrugated flexible strip has a thermal
conductive material flat strip bonded (connected) to one side of
the corrugated strip forming a single-faced flexible corrugated
strip. Another embodiment employs two flat flexible strips of
thermal conductive material each bonded to each side of the
flexible corrugated strip forming a double-faced flexible
corrugated strip. In both the single-faced and double-faced
flexible corrugated strips, an adhesive is used to adhere the strip
to the integrated circuit device and the adhesive is preferably on
the flat flexible strip.
[0021] In yet another aspect of the invention the adhesive used is
thermally conductive to enhance the heat dissipation properties of
the corrugated tape article.
[0022] Another aspect of the invention is directed to a method to
enhance integrated circuit device heat dissipation comprising the
steps of:
[0023] providing an integrated circuit device having a surface;
[0024] providing a strip of flexible flat thermal conductive
material;
[0025] forming corrugations in the flexible thermal conductive
material if desired; and
[0026] adhering the flat or corrugated flexible thermal conductive
material to the surface of the integrated circuit.
[0027] In another aspect of the invention the flexible thermal
conductive material which has been corrugated may be fed from the
corrugation step directly to the surface of the integrated circuit
to provide a continuous system for making the corrugated tape and
applying the corrugated tape to the integrated circuit in a
sequential series of operations.
[0028] In yet another aspect of the invention, after forming the
corrugations in a flexible strip of thermal conductive material,
either one or more flat strips of thermal conductive material may
be bonded to one or both sides of the corrugated material to form a
single-face or double-face thermal conductive material corrugated
tape article for application to the surface of the integrated
circuit device.
[0029] In another aspect of the invention an article of manufacture
is provided for dissipating heat for integrated circuit and other
electronic component devices comprising a flexible flat or
preferred corrugated strip of thermal conductive material
preferably having an adhesive thereon which adhesive contacts and
adheres the strip to the surface of the integrated circuit device.
Other articles of manufacture embodiments include a single-faced or
a double-faced corrugated thermal conductive material tape
preferably with an adhesive thereon. A preferred article of the
invention provides a thin coating on the surface of the strip such
as a varnish, paint, anodized layer, oxide layer, etc. to increase
the heat emissivity of the article.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The features of the invention believed to be novel and the
elements characteristic of the invention are set forth with
particularity in the appended claims. The figures are for
illustration purposes only and are not drawn to scale. The
invention itself, however, both as to organization and method of
operation, may best be understood by reference to the detailed
description which follows taken in conjunction with the
accompanying drawings in which:
[0031] FIGS. 1A, 1B and 1C show different tape articles of the
invention applied to the surface of an integrated circuit chip for
cooling the chip.
[0032] FIGS. 2A, 2B, 2C, 2D and 2E show different corrugated tape
articles of the invention.
[0033] FIGS. 3A, 3B, 3C, 3D and 3E show other corrugated tape
articles of the invention.
[0034] FIGS. 4A, 4B, 4C, 4D and 4E show additional corrugated tape
articles of the invention.
[0035] FIG. 5 shows an electronic component having within the
component housing a chip containing electronic component assembly
cooled using a tape article of the invention.
[0036] FIG. 6A shows a method and apparatus for forming
corrugations in a flat metal tape to form a corrugated tape article
of the invention which is used to cool integrated circuit
devices.
[0037] FIG. 6B shows another method and apparatus of the invention
for forming a corrugated metal tape article from a flat tape which,
after forming, is applied directly to the surface of an integrated
circuit device.
[0038] FIGS. 7A and 7B show prior art methods of dissipating heat
on integrated circuit devices.
DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0039] In describing the preferred embodiment of the present
invention, reference will be made herein to FIGS. 1A-7B of the
drawings in which like numerals refer to like features of the
invention. Features of the invention are not necessarily shown to
scale in the drawings.
[0040] Broadly stated, this invention comprises using a thermally
conductive flexible material preferably with an extended surface
area which is applied to the surface of an electronic component to
thermally enhance heat dissipation from the electronic component
such as IC devices.
[0041] The preferred heat dissipation article of the invention
comprises two components. One component is a flexible thermal
conductive material strip such as copper, aluminum, gold, silver,
phosphor, bronze, beryllium copper and other metal or thermal
conductive materials which has been preferably corrugated. The
other component is an adhesive material which can be either a
pressure sensitive or other kind known in the art. By using a label
process, the flexible layer of copper, aluminum, or other high
thermal conductivity material strip can be coated with an adhesive
or pressure sensitive material to form the heat dissipation article
of the invention. The strip may also be used without an adhesive
thereon but an adhesive would be needed to adhere the strip to the
IC device.
[0042] The flexible thermal conductive material is much thinner and
lower mass than the traditional inflexible heat spreader and heat
sink structures of the prior art as shown in FIGS. 7A and 7B and is
a very small mass relative to the IC device or other material
surface to which it is applied. This offers a significant
mechanical and conformal compliance with the IC device during
thermal cycling of the IC device and the IC devices survive shock
and vibration tests as compared to the traditional heat spreader
and heat sink devices which may more easily become separated from
the IC device because of adhesive failure.
[0043] Tables 1 and 2 below illustrate and compare the thermal
performance of a flat, non-corrugated tape article of this
invention. Table 1 and 2 show the thermal benefit using a metal
tape as compared with standard package in PQFP and PBGA,
respectively. Thus, using a tape and increasing the thickness of
the tape decreases the thermal resistance R and increases the heat
dissipation of the device to which the tape is attached.
1 TABLE 1 Heatsink % Heat Dissipation Thickness R_ja C/w
Improvement No Heatsink 16.9 0 10 micron 16 5 30 micron 15.8 7 40
micron 14.9 13 50 micron 14.6 16
[0044]
2 TABLE 2 Heatsink % Heat Dissipation Thickness R_ja C/w
Improvement No Heatsink 49.7 0 10 micron 37.6 23 30 micron 32.8 50
40 micron 31.1 60 50 mcron 29.3 70
[0045] Table 3 shows the data for PQFP implementation with air flow
across the device. The use of a tape label lowers the thermal
resistance R of the device to which the tape is applied.
3 TABLE 3 % Heat Dissipation R_ja C/w Improvement Low air No
Heatsink 64 0 Low air flow Heatsink 42 52 Forced air No Heatsink 53
0 Forced air Heatsink 35.7 48
[0046] Table 4 shows the thermal performance of a tape article of
the invention based on varying the tape thickness.
4 TABLE 4 % Heat Dissipation Heatsink Thickness R_ja C/w
Improvement No Heatsink 47 0 10 micron Heatsink 41 13 20 micron
Heatsink 39.5 16 30 micron Heatsink 38 19 40 micron Heatsink 37 21
50 micron Heatsink 36.2 22 75 micron Heatsink 35 25.5 100 micron
Heatsink 34 27.5 200 micron Heatsink 32.8 30 300 micron Heatsink
31.5 33
[0047] The improved heat dissipation properties for an enhanced
surface area tape of the invention are presented in Table 5. The
results show that the enhanced surface area label tape article of
the invention has higher heat transfer properties than increasing
the thickness of a flat tape and is preferred for most applications
requiring heat dissipation.
5 TABLE 5 % Heat Dissipation R_ja C/w Improvement No Heatsink 47 0
30 micron Heatsink 38 19 30 micron adding 31.2 34 250% area 30
micron adding 28 40 360% area 30 micron adding 24 49 500% area
[0048] The strip material and adhesive and their dimensions may
vary widely. A one mil thick metal strip has been found suitable
for most applications but can vary up to about 10 mil or higher.
The adhesive is typically 0.5 to 5 mil thick.
[0049] The corrugated article can then be fabricated using methods
such as forming the corrugations by feeding the thin metal through
turning meshed gears as shown in FIG. 6A and FIG. 6B. Attachment of
the body to a heating surface (IC device) can be done by a direct
attachment at room temperature.
[0050] This invention can use all metal materials and adhesive
materials and because of the small mass on the metal side, the tape
is very light in weight and offers a strong bonding to the surface
to which it is attached. As discussed above, previous designs
require specially defined adhesive materials due to the large mass
involved in the heat spreader or heat sink metal part whereas the
tape of the invention requires only a thin metal material strip and
many standard adhesives may be used. Additionally the formed
metallic tape can be used as a comformable thermal connection from
the semiconductor device to the enclosure of the electrical
assembly as seen in FIG. 5.
[0051] Referring firstly to FIGS. 7A and 7B, these figures show
heat dissipation devices of the prior art which are not acceptable
for a number of reasons including cost, effectiveness, difficulty
of fabrication and operating life.
[0052] FIG. 7A shows an electronic component 115 comprising a chip
116 having a heat spreader of 117 on the surface thereof and a heat
dissipation device containing fins 118 on top of the heat spreader.
As is known in the art, heat spreaders and heat dissipation fin
devices are solid structural devices which have considerable weight
and are expensive.
[0053] Referring to FIG. 7B, another integrated circuit device 119
comprises a chip 120 and a heat dissipation fm device 122 which is
adhered to the chip using a thermal paste 121.
[0054] The structures 118 and 122 in FIGS. 7A and 7B are typically
about 3 to 20 mm thick.
[0055] Referring now to FIGS. 1A, 1B and 1C, three different tape
articles of the invention having a triangular corrugation are shown
attached to chips for cooling the chip. In FIG. 1A, an integrated
circuit device shown generally as 10 comprises a chip 11, and a
corrugated metal tape article 12 adhered to the chip by adhesive 13
wherein the adhesive is applied to the distal portion of one side
of the corrugated metal tape article, and the distal portion is in
contact with the chip surface.
[0056] In FIG. 1B, another integrated circuit device shown
generally as 14 comprises a chip 15 having a corrugated tape
article 19 attached to the chip. Corrugated tape article 19
comprises a corrugated metal strip 16 bonded to a flat metal strip
17 which has an adhesive 18 thereon for applying and adhering the
tape article 19 to the chip 15. This is an example of a single-face
tape article.
[0057] In FIG. 1C, a double-faced corrugated tape article 26 is
shown adhered to chip 21 forming component assembly 20. The
corrugated tape article 26 comprises a corrugated metal strip 22
with flat metal strips 23 and 24 bonded to opposed distal sides of
the corrugated metal 22. An adhesive 25 on metal strip 23 is used
to adhere the corrugated tape article 26 to chip 21.
[0058] Referring now to FIGS. 2A-2E, a number of different tape
article structures of the invention are shown.
[0059] In FIG. 2A, tape article 27 comprises a corrugated metal 28
having a triangular shape with repeating opposed angled sidewalls
28a and 28b. Adhesive 29 is applied to the distal end of the
corrugated metal 28 for adherence to a chip or other IC device.
This embodiment shows a coating 28c on the surface of metal 28 to
increase the emissivity of the device. The coating 28c may be an
oxide, varnish, paint, etc. and is typically about 0.05 mil to 1
mil thick.
[0060] FIG. 2B shows tape article 30 comprising a repeating series
of convex and concave portions comprising opposed vertical sidewall
portions 31a and 31c, top connecting horizontal portion 31b and
connecting bottom horizontal portion 31d. An adhesive 32 is applied
to the lower part of bottom portion 31d for adherence to a chip or
other IC device.
[0061] FIG. 2C shows a corrugated tape article 33 comprising a
repeating series of convex portions comprising angled opposed
sidewalls 34a and 34c, a top connecting horizontal portion 34b and
connecting concave triangular portions. An adhesive 35 is applied
at the base of the concave triangular portions for adherence of the
tape article to a chip or other IC device.
[0062] FIG. 2D shows a fin type corrugated tape article 36
comprising a corrugated metal 37 having a repeating series of
vertical opposed sidewalls 37a and 37c, a top connecting portion
37b and a bottom connecting portion 37d. An adhesive 38 is applied
to the lower part of bottom portion 37b for adherence of the tape
article 36 to a chip or IC device.
[0063] FIG. 2E shows a loop type corrugated tape 39. The loop of
material 40 comprises opposed sidewalls 40b and 40d and a
connecting upper portion 40c and a connecting lower portion 40a. An
adhesive 41 is applied to the lower portion of bottom portion 40a
for adherence to an integrated circuit device.
[0064] FIGS. 3A-3E parallel FIGS. 2A-2E with the difference being
the use of a flat metal strip along the one distal side of the
corrugated metal forming a single-faced corrugated article sheet.
Thus, in FIG. 3A, a triangular corrugated metal tape article 42 is
shown as triangular metal strip 43 with a flat metal strip 44
bonded at the lower juncture of triangular sidewalls 43a and 43b.
An adhesive 45 is applied to the bottom of flat metal strip
adhesive 44 for adherence to an integrated circuit device.
[0065] FIG. 3B shows a tape article 46 comprising a repeating
series of convex and concave portions 47 having vertical opposed
sidewalls 47a and 47c, a connecting top horizontal portion 47b and
a connecting lower horizontal portion 47d. A flat metal strip 48 is
bonded to the lower part of lower portion 47d and an adhesive 49 is
applied thereto for adherence to an integrated circuit device.
[0066] FIG. 3C shows a corrugated single-faced tape article 50
comprising a corrugated metal 51 comprising a repeating series of
convex portions having angled opposed sidewalls 51a and 51c and a
connecting top horizontal portion 51b. A flat metal strip 52 is
bonded at the juncture of the angled sidewalls and an adhesive 53
is applied to the lower portion of metal tape 52.
[0067] FIG. 3D shows a corrugated tape article 54 of the invention
comprising a repeating series of vertical fins 55 having vertical
opposed sidewalls 55a and 55c, an upper connecting portion 55b and
a lower connecting portion 55d. A flat metal strip 56 is bonded to
the corrugated metal at the lower portion of 55d and an adhesive 57
is applied to the metal strip.
[0068] In FIG. 3E, a corrugated tape article 58 is shown comprising
a series of loops 59 which loops have opposed sidewalls 59b and
59d, a connecting upper portion 59c and a connecting lower portion
59a. A thin flat metal strip 60 is bonded to the bottom of the
lower portion 59a and an adhesive 61 is applied to the bottom of
the metal strip 60.
[0069] FIGS. 4A-4E parallel FIGS. 2A-2E and 3A-3E and show
double-faced tape articles of the invention.
[0070] In FIG. 4A a tape article shown as 62 comprises a corrugated
triangular portion 63 having angled opposed sidewalls 63a and 63b.
A flat metal strip 64 and a second flat metal strip 65 are bonded
at opposite sides of the corrugated metal portion 63 and an
adhesive 66 is applied to the bottom of strip 64 for adherence to
an integrated circuit device.
[0071] In FIG. 4B, a tape article shown as 67 comprises a
corrugated metal portion 68 comprising a repeating series of convex
and concave portions comprising opposed vertical sidewalls portions
68a and 68c, a top connecting horizontal portion 68b and a lower
connecting horizontal portion 68d. A flat metal strip 69 is bonded
to the lower portion 68d and a second flat metal strip is bonded to
the upper portion 68b forming a double-faced tape. An adhesive 71
is shown applied to the bottom of metal strip 69 for adherence to
an integrated circuit device.
[0072] Referring to FIG. 4C, a corrugated tape article 72 is shown
having a corrugated metal portion 73 comprising a repeating series
of convex portions comprising angled opposed sidewalls 73a and 73c
and a connecting horizontal top portion 73b. A flat metal strip 74
is bonded to corrugated metal structure 73 at the juncture of the
angled sidewalls and another flat metal strip 75 is bonded to the
top portion 73b. A double-faced tape article is thus formed and an
adhesive 76 is applied to the bottom of tape 74 for adherence to an
integrated circuit device.
[0073] In FIG. 4D, a tape article 77 is shown having a corrugated
metal portion 78 comprising a repeating series of vertical fins
comprising vertical opposed sidewalls 78a and 78c, a connecting top
portion 78b and a connecting lower portion 78d. A flat metal strip
79 is bonded to the corrugated metal portion 78 at the lower
portion 78d and another metal strip 80 is bonded to the structure
at the top portion 78b. An adhesive 81 is applied to the bottom of
metal strip 79 for adherence to an integrated circuit device.
[0074] FIG. 4E shows a loop double-faced tape article 82 comprising
a loop metal corrugated structure 83 comprising opposed sidewalls
83a and 83c, an upper portion 83b and a lower portion 83d. A flat
metal strip 84 is bonded to lower portion 83d and a different flat
metal strip 85 bonded to upper portion 83b. An adhesive 86 is
applied to the lower portion of strip 84 for adherence to an
integrated circuit device.
[0075] FIG. 5 shows use of a tape article 87 of the invention to
dissipate heat in an electronic component such as a portable
computer or portable phone, etc. The electronic component has a
lower housing 88 and an opposed upper housing 93. A printed circuit
board or other electronic device 89 is secured in the component and
is attached to chip 91 through solder balls 90. On top of chip 91
is placed a tape article of the invention shown in composite as
numeral 92. Tape article 92 comprises a corrugated triangle metal
portion 94 having opposed angled flat metal sides 94a and 94b.
Adhesive 97 is applied to bonded metal strip 95 and adhesive 98
applied to bonded metal strip 96 to adhere the tape device 92 to
chip 91 and upper housing 93, respectively. If upper housing 93 is
a metal housing or a plastic housing with a thin metal deposited on
its inner surface (shown as 93b) often done for shielding, greater
thermal improvement will be achieved.
[0076] FIG. 6A shows one method for making a corrugated tape
article of the invention. Thus, a flat metal tape 99 is fed between
revolving intermeshing gears 100 and 101 having a meshing gear
structure 100a and 101a, respectively. Upon passing of the metal
tape through the gears, a corrugated metal tape 102 is formed
having a structure formed by the meshing gears. This tape
corresponds generally to the tape shown in FIG. 2B. Other
corrugated tape articles could be formed depending on the shape of
the gears.
[0077] FIG. 6B shows the sequential continuous steps of forming a
corrugated tape article of the invention and applying the
corrugated tape article to the surface of an integrated circuit
component. Thus, a metal tape spool 103 feeds out a metal strip 104
which passes through gears 105 and 106 having meshing corrugations
105a and 106a. The corrugated tape 107 may be cut using cutter 111
when desired and an adhesive also applied to the tape using
applicator 112. Tape article 107 is shown applied to the surface of
chip 108 which chip is part of electronic component 110 having a
solder ball connection 109 to chip 108.
[0078] While the present invention has been particularly described,
in conjunction with a specific preferred embodiment, it is evident
that many alternatives, modifications and variations will be
apparent to those skilled in the art in light of the foregoing
description. It is therefore contemplated that the appended claims
will embrace any such alternatives, modifications and variations as
falling within the true scope and spirit of the present
invention.
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