A HEAT DISSIPATION DEVICE AND
A SYSTEM INCORPORATING THE SAME
This invention relates generally to a heat dissipation device and a system and
method for an integrated circuit assembly, and more particularly to a system and
method of dissipating heat from an integrated circuit device.
Background
Integrated circuit devices, microprocessors and other related computer
components are becoming more and more powerful with increasing capabilities,
resulting in increasing packaging densities and amounts of heat generated from
these components. Packaged units and integrated circuit device sizes of these
components are decreasing or remaining the same, but the amount of heat energy
given off by these components per unit volume, mass, surface area or any other
such metric is increasing. In current packaging techniques, heat sinks typically
consist of a flat base plate, which is mounted onto the integrated circuit device on
one side. The heat sinks further include an array of fins running perpendicular to
the flat base plate on the other side. Generally, the integrated circuit devices
(which are the heat sources) have a significantly smaller footprint size than the
flat base plate of the heat sink. The flat base plate of the heat sink
has a large footprint. The large footprint requires more motherboard real estate
than the integrated circuit device in contact therewith. The larger size of the base
plate causes the outermost part of the base plate that is not directly in contact with
the integrated circuit device to have a significantly lower temperature than the
part of the base plate that is directly in contact with the integrated circuit device.
This results in the outermost part of the heat sink that is not directly in contact
with the integrated circuit less efficient in dissipating heat into the cooling air.
Furthermore, as computer-related equipment becomes more powerful, more
components are being placed inside the equipment and on the motherboard which
further requires more motherboard real estate. In addition, the base plate of prior
art heat sink designs is at the same level as the integrated circuit device to which
it is attached. Consequently, the flat base plate configuration of the heat sink
generally ends up consuming more motherboard real estate than the integrated
circuit device on which it is mounted. As a result, the larger footprint size of the
base plate prevents other motherboard components, such as low-cost capacitors,
from encroaching around or on the microprocessor. Thus, the large amounts of

heat produced by many of such integrated circuits, and the increasing demand for
motherboard real estate need to be taken into consideration when designing the
integrated circuit mounting and packaging devices.
Accordingly, the present invention provides a heat dissipation device
comprising : a thermally conductive core, wherein the core has an axis, wherein the
core has a base to mount upon an integrated circuit device, wherein the base is
perpendicular to the axis, and wherein the core has upper and lower outer surface
areas concentric to the axis and having first and second lengths, respectively ; a
first array of radially extending fin structures, the first array being thermally coupled
to the upper outer surface area along the first length, wherein the first array has a
first outer diameter ; and a second array of radially extending fin structures, the
second array being thermally coupled to the lower outer surface area along the
second length, wherein the second array has a second outer diameter, the second
outer diameter being less than the first outer diameter, and wherein the second
length and the second outer diameter are sized to provide sufficient space below
the first array to allow components to be mounted around and in close proximity to
the lower outer surface area and below the first array when the base of the heat
dissipation device is mounted on an integrated circuit device.
The present invention also provides a heat dissipation system
comprising : an integrated circuit device having a front side and a back side
opposite the front side, wherein the front side is attached to a surface of a circuit
board, the surface of the circuit board having components mounted thereof and
projecting outwardly from the surface ; and a heat dissipation device comprising : a
thermally conductive core having a base thermally coupled to the back side of the
integrated circuit device, the core having an axis perpendicular to the base, and the
core further having upper and lower outer surface areas concentric to the axis
and having first and second

lengths, respectively ; a first array of radially extending fin structures, the first array
being thermally coupled to the upper outer surface area along the first length,
wherein the first array has a first outer diameter ; and a second array of radially
extending fin structures, the second array being thermally coupled to the lower
outer surface area along the second length, wherein the second array has a
second outer diameter, the second outer diameter being less than the first outer
diameter, and wherein the second length and the second outer diameter are sized
to provide sufficient space for the components around and in close proximity to the
lower outer surface area and below the first array.
The present invention further provides an article comprising : a
thermally conductive core extending upwardly from a heat producing device
mounted on a substrate ; a first array of fin structures extending radially outwardly
from an upper portion of the core to define a first cross-sectional shape ; and a
second array of fin structures extending radially outwardly from a lower portion of
the core to define a second cross-sectional shape, wherein the area of the second
cross-sectional shape is less than the area of the first cross-sectional shape and
wherein the second cross-sectional shape is sized to provide sufficient clearance
for components mounted on the substrate around and in close proximity to the
second array of fin structures and extending within a perimeter of the first cross-
sectional shape.
For the reasons stated above, and for other reasons stated below which
will become apparent to those skilled in the art upon reading and understanding the
present specification, there is a need in the art for an enhanced heat dissipation
device and method that conserve motherboard real estate and allow electronic
components to encroach on and around the microprocessor.

For the reasons stated above, and for other reasons stated below which will
become apparent to those skilled in the art upon reading and understanding the
present specification, there is a need in the art for an enhanced heat dissipation
device and method that conserve motherboard real estate and allows electronic
components to encroach on and around the microprocessor.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 is an isometric view of a prior art heat sink attached to a
microprocessor on an assembled motherboard.
Figure 2 is an isometric view of one embodiment of an enhanced heat
dissipation device according to the present invention.
Figure 3 is an isometric view showing the enhanced heat dissipation device
of Figure 2 attached to a microprocessor on an assembled motherboard.
Figure 4 is an isometric view of another embodiment of an enhanced heat
dissipation device according to the present invention.
Figure 5 is an isometric view showing the enhanced heat dissipation device
of Figure 4 attached to a microprocessor on an assembled motherboard.
Figure 6 is an isometric view of another embodiment of an enhanced heat
dissipation device according to the present invention.
Figure 7 is an isometric view showing the enhanced heat dissipation device
of Figure 6 attached to a microprocessor on an assembled motherboard.
Detailed Description
In the following detailed description of the embodiments, reference is made
to the accompanying drawings that illustrate the present invention and its
practice. In the drawings, like numerals describe substantially similar components
throughout the several views. These embodiments are defilibed in sufficient
detail to enable those skilled in the art to practice the invention. Other
embodiments may be utilized and structural, logical, and electrical changes may
be made without departing from the scope of the present invention! Moreover, it
is to be understood that the various embodiments of the invention, although
different, are not necessarily mutually exclusive. For example, a particular
feature, structure, or characteristic described in one embodiment may be included
in other embodiments. The following detailed description is, therefore, not to be

taken in a limiting sense, and the scope of the present invention is defined only
by the appended claims along with the full scope of equivalents to which such
claims are entitled.
This document describes, among other things, an enhanced heat dissipation
device that allows electronic components to encroach around and on a
microprocessor while maintaining high performance and cost effectiveness by
leveraging currently enabled high-volume manufacturing techniques.
Figure 1 shows an isometric view 100 of a prior art heat sink 110 mounted
on a microprocessor 120 of an assembled motherboard 130. Also, shown in
Figure 1 are low-cost capacitors 140 mounted around the heat sink 110 and on
the motherboard 130.
The prior art heat sink 100 has a flat base plate 150 including an array of
fins 160 extending perpendicularly away from the flat base plate 150. This
configuration of the heat sink 110 dictates the use of the flat base plate 110, with
the array of fins 160 for dissipating heat from the microprocessor 120. Increasing
the heat dissipation using the prior art heat sink 110 shown in Figure 1, generally
requires enlarging the surface area of the flat base plate 150 and/or the array of
fins 160. This in turn results in consuming more motherboard real estate.
Generally, the microprocessor 120 (which is the heat source) has a smaller
footprint size than the flat base plate 150 configuration of the heat sink 110
shown in Figure 1. A larger footprint size of the flat base plate 150 can cause the
outermost part of the flat base plate 150 (the portion that is not directly in contact
with the integrated circuit device) to have a significantly lower temperature than
the part of the flat base plate 150 that is directly in contact with the integrated
circuit device. Consequently, the prior art heat sink 110 with the larger flat base
plate 150 is not effective in dissipating from the targated circuit device.
Furthermore, the packaged units and integrated circuit device sizes are
decreasing, while the amount of heat generated by these components is
increasing. The prior art heat sink 110 configaration dictates that the array of fins
160 extend to the edge of the flat base plate 150 to extract heat from the
integrated circuit device. Also, the prior art heat sink 110 requires increasing the
size of the array of fins 160 to increase the heat dissipation. In order to enlarge
the fins 120 laterally, the flat base plate 150 has to increase in size. Enlarging the
flat base plate 150 consumes more motherboard real estate. Consuming more
motherboard real estate is generally not a viable option in an environment where
system packaging densities are increasing with each successive, higher
performance, integrated circuit device generation. Also, the prior art heat sink

110 is at the same level as the integrated circuit device on which it is mounted. It
can be seen in Figure 1, that the flat base plate 150 configuration of the prior art
heat sink 110 mounted on the microprocessor 120 generally prevents other
motherboard components, such as low-cost capacitors 140, from encroaching
around the microprocessor 120.
Figure 2 is an isometric view of one embodiment of the enhanced heat
dissipation device 200 according to the present invention. Shown in Figure 2 is
the enhanced heat dissipation device 200 including a thermally conductive core
210, and a first array of radially extending pin fin structures 220. The pin
structures can have cross- sectional shapes such as round, square, rectangle,
elliptical, conical or any other suitable shape for dissipating heat. Also, shown in
Figure 2 is the core 210 having upper and lower outer surface areas 230 and 240.
The first array 220 is thermally coupled to the upper surface area 230 of the core
210 such that a cooling medium such as air introduced around the upper and
lower surface areas 230 and 240 of the core 210 and the first array 220 creates an
omni-directional flow around the core 210 and the first array to enhance heat
dissipation from the heat sink 200. Figure 2 further shows an optional second
array of radially extending pin fin structures 290 thermally coupled to the lower
surface area 240 of the core 210 such that the cooling medium introduced around
the second array also creates an omni-directional flow around the second array
290. Each of the pin structures can have a head to create a higher turbulent flow
around the first and second arrays 220 and 290.
The core 210 has an axis 260. In some embodiments, the upper and lower
surface areas 230 and 240 are parallel to the axis 260. The core 260 further has a
base 270. In some embodiments, the base 270 is disposed in such a way that it is
in close proximity to the lower surface area 240 and perpendicular to the axis
260. The upper and lower surface areas 230 and 240 can be concentric to the axis
260.
The first array 220 is thermally coupled to the upper surface area 230 such
that components can be mounted around and in close proximity to the lower
surface area 240 and below the first array 220 when the device 200 is mounted
onto an integrated circuit device. In some embodiments, the components can
encroach onto the integrated circuit device without mechanically interfering with
the device 200.
The core 210 can be a solid body. The solid body can be cylindrical,
conical, square, rectangular, or any other similar shape that facilitates in
mounting onto the integrated circuit device and in attaching the first array 220 to

the upper surface area 230. The core 210 can include heat transport mediums
such as one or more heat pipes, a liquid, a thermo-siphon, or other such heat
transport medium that enhance heat dissipation from the integrated circuit device.
In some embodiments, the first array 220 has a first outer diameter 250 and
the second array 290 has a second outer diameter 255. The second outer diameter
255 is less than the first outer diameter 250. The first array 220 has a first depth
and the second array 290 has a second depth. The first and second outer
diameters 250 and 255 including the first and second depths are of sufficient size
to allow components to be mounted around and in close proximity to the
integrated circuit device when the device is mounted on the integrated circuit
device.
The second array 290 is thermally coupled to the lower core area 240 of the
core 210 such that the cooling medium introduced around the first and second
arrays 220 and 290 creates an omni-directional flow around the upper and lower
surface areas 230 and 240 of the core 210 and the first and second arrays 220 and
290 to enhance heat dissipation from the heat sink 200. The device 200, including
the core 210 and the first and second arrays 220 and 290, can be made from
materials such as aluminum, copper, or any other materials that are capable of
dissipating heat away from the integrated circuit device. The first and second
arrays 220 and 290 can be formed to have outer shapes such as circular, square,
rectangular, elliptical, conical or any other shape suitable for allowing
components to encroach around and in close proximity to the first and second
arrays 220 and 290.
Figure 3 is an isometric view 300 showing the enhanced heat dissipation
device 200 shown in Figure 2, attached to the microprocessor 120 on an
assembled motherboard 130. In the example embodiment shown in Figure 3, the
microprocessor 120 has a front side 340 and a back side 330. The front side 340
is disposed across from the back side 330. The front side 340 is attached to the
assembled motherboard 130 that has components such as low-cost capacitors 140
and other such electrical components. The base 270 shown in Figure 2, of the
enhanced heat dissipation device 200, is attached to the back side 330 of the
microprocessor 120. It can be seen from Figure 3 that the first and second arrays
220 and 290 are of sufficient size so as to allow low-cost capacitors 140 mounted
on the assembled board 130 to encroach around the microprocessor 120. It can
also be seen that the low-cost capacitors 140 are below the first array 220 and
around the second array 290.
Also, it can be seen in Figure 3 that the first array 220 is larger than the

second array 290, thereby increasing the heat dissipation rate without increasing a
footprint size of the base 270 of the heat dissipation device 200 any more than the
back side 330 of the microprocessor 120. The coinciding footprint sizes of the
base 270 of the heat dissipation device 200 and the back side 330 of the
microprocessor 120 enables the base 270 and the back side 330 of the
microprocessor 120 to have the same heat transfer rates. This in turn increases the
efficiency of heat transfer between the base 270 and the back side 330 of the
microprocessor 120.
The core 210 further has a top surface 275 disposed across from the base
270. In some embodiments, the top surface 275 is perpendicular to the axis 260
and is in close proximity to the first array 220. A heat transport medium can be
attached to the top surface 275 to introduce a heat transfer medium 297 such as
air in a direction shown in Figure 2. This creates an omni-directional flow around
the core 210 and the first and second arrays 220 and 290 to enhance heat
dissipation by the heat dissipation device 200. A heat transport medium 295 such
as a heat pipe, or other such medium can be included in the core 210 to further
enhance the heat transfer from the heat dissipation device 200.
In some embodiments, the enhanced heat dissipation device 200 is made of
thermally conductive materials such as copper, aluminum, or any other such
material capable of extracting heat away from the integrated circuit device. In
some embodiments, the core 210 can include heat transport mediums such as one
or more heat pipes, a liquid, a thermo-siphon, or other similar heat transport
medium suitable for enhancing the extraction of heat from the integrated circuit
device. In some embodiments, the first and second arrays 220 and 290 occupy a
first and second volume of space, respectively around the upper and lower
surface areas 230 and 240 such that the first volume is less than the second
volume to permit components to be mounted on the circuit board 130 and below
the first array 220.
Figure 4 is an isometric view of another embodiment of the enhanced heat
dissipation device 400 according to the present invention. Shown in Figure 4 is
the enhanced heat dissipation device 400 including the thermally conductive core
210, and a first array of radially extending substantially planar fin structures 420.
Also, shown in Figure 4 is the core 210 having the upper and lower outer surface
areas 230 and 240. The first array 420 is thermally coupled to the upper surface
area 230 of the core 210 such that a cooling medium such as air introduced
around the upper and lower surface areas 230 and 240 of the core 210 and the
first array 420, creates a flow that is substantially parallel to the upper and lower

surface areas 230 and 240 and the first array 420 to enhance heat dissipation from
the heat sink 400. Figure 4 further shows an optional second array of radially
extending substantially planar fin structures 490 thermally coupled to the lower
surface area 240 of the core 210 such that the cooling medium introduced around
the first and second arrays 420 and 490 creates a flow that is substantially parallel
to the upper and lower surface areas 230 and 240 and the first and second arrays
420 and 490.
The core 210 has an axis 260. The substantially planar fin structures of the
first and second arrays 420 and 490 are thermally coupled to the upper and lower
surface areas 230 and 240, respectively such that they are substantially parallel to
the axis so that the cooling medium introduced around the core 210 and the first
and second arrays 420 and 490, creates a flow substantially parallel to the axis
260 to enhance heat dissipation from the heat sink 400. In some embodiments,
the first and second arrays 420 and 490 including the substantially planar fin
structures are aligned and thermally coupled so that they form a single array as
shown in Figure 4. In some embodiments, the upper and lower surface areas 230
and 240 are parallel to the axis 260. The core 260 further has a base 270. In some
embodiments, the base 270 is disposed such a way that it is in close proximity to
the lower surface area 240 and perpendicular to the axis 260. The upper and
lower surface areas 230 and 240 can be concentric to the axis 260.
The first array 420 is thermally coupled to the upper surface area 230 such
that components can be mounted around and in close proximity to the lower
surface area 240 and below the first array 420 when the device 400 is mounted
onto an integrated circuit device. In some embodiments, the components can
encroach onto the integrated circuit device without mechanically interfering with
the device 400.
The core 210 can be a solid body. The solid body can be cylindrical,
conical, square, rectangular, or any other similar shape that facilitates in
mounting onto the integrated circuit device and in attaching the first array 420 to
the upper surface area 230. The core 210 can include heat transport mediums
such as one or more heat pipes, a liquid, a thermo-siphon, or other such heat
transport medium that enhance heat dissipation from the integrated circuit device.
The first array 420 has the first outer diameter 250 and the second array
490 has the second outer diameter 255. The second outer diameter 255 is less
than the first outer diameter 250. The first array 420 has a first depth and the
second array 490 has a second depth. The first and second outer diameters 250
and 255 including the first and second depths, are of sufficient size to allow

components to be mounted around and in close proximity to the integrated circuit
device when the device is mounted on the integrated circuit device.
The second array 490 is thermally coupled to the lower core area 240 of the
core 210 such that the cooling medium introduced creates an omni-directional
flow around the upper and lower surface areas 230 and 240 of the core 210 and
the first and second arrays 420 and 490 to enhance heat dissipation from the heat
sink 400. The device 400, including the core 210 and the first and second arrays
420 and 490, can be made from materials such as aluminum, copper, or any other
materials that are capable of dissipating heat away from the integrated circuit
device. The first and second arrays 420 and 490 can be formed to have outer
shapes such as circular, square, rectangular, elliptical, conical or any other shape
suitable for allowing components to encroach around and in close proximity to
the first and second arrays 420 and 490.
Figure 5 is an isometric view 500 showing the enhanced heat dissipation
device 400 shown in Figure 4, attached to the microprocessor 120 on the
assembled motherboard 130. In the example embodiment shown in Figure 5, the
microprocessor 120 has a front side 340 and a back side 330. The front side 340
is disposed across from the back side 330. The front side 340 is attached to the
assembled motherboard 130 having components such as low-cost capacitors 140
and other such electrical components. The base 270 shown in Figure 4, of the
enhanced heat dissipation device 400 attached to the back side 330 of the
microprocessor 120. It can be seen from Figure 4 that the first and second arrays
420 and 490 are of sufficient size so as to allow low-cost capacitors 140 mounted
on the assembled board 130 to encroach around the microprocessor 120. It can
also be seen that low-cost capacitors 140 are below the first array 420 and around
the second array 490.
Also, it can be seen in Figure 4 that the first array 420 is larger than the
second array 490, thereby increasing the heat dissipation rate without increasing a
footprint size of the base 270 of the heat dissipation device 400 any more than the
back side 330 of the microprocessor 120. The coinciding footprint sizes of the
base 270 of the heat dissipation device 400 and the back side 330 of the
microprocessor 120 enables the base 270 and the back side 330 of the
microprocessor 120 to have same heat transfer rates. This in turn increases the
efficiency of heat transfer between the base 270 and the back side 330 of the
microprocessor 120.
The core 210 further has the top surface 275 disposed across from the base
270. In some embodiments, the top surface 275 is perpendicular to the axis 260

and is in close proximity to the first array 420. A heat transport medium can be
attached to the top surface 275 to introduce a heat transfer medium 297 such as
air in a direction shown in Figure 2, to create a flow around the core 210 and the
first and second arrays 420 and 490 that is substantially parallel to the core 210
and the first and second arrays 420 and 490 to enhance the heat dissipation by the
heat dissipation device 400. A heat transport medium 295 such as a heat pipe, or
other such medium can be included in the core 210 to further enhance the heat
transfer from the heat dissipation device 400.
In some embodiments, the enhanced heat dissipation device 400 is made of
thermally conductive materials such as copper, aluminum, or any other such
material capable of extracting heat away from the integrated circuit device. In
some embodiments, the core 210 can include heat transport mediums such as one
or more heat pipes, a liquid, a thermo-siphon, or other similar heat transport
medium suitable for enhancing the extraction of heat from the integrated circuit
device. In some embodiments, the first and second arrays 420 and 490 occupy a
first and second volume of space around the upper and lower surface areas 230
and 240 such that the first volume is less than the second volume to permit
components to be mounted on the circuit board 130 and below the first array 420.
Figure 6 is an isometric view of another embodiment of the enhanced heat
dissipation device 600 according to the present invention. Shown in Figure 6 is
the enhanced heat dissipation device 600 including the thermally conductive core
210, and a first array of radially extending substantially planar fin structures 620.
Also, shown in Figure 6 is the core 210 having upper and lower outer surface
areas 230 and 240. The first array 620 is thermally coupled to the upper core area
230 of the core 210 such that a cooling medium such as air introduced around the
upper and lower surface areas 230 and 240 of the core 210 and the first array 620
creates a flow that is substantially perpendicular to the core 210 to enhance heat
dissipation from the device 600. Figure 6 further shows an optional second array
of radially extending substantially planar fin structures 690 thermally coupled to
the lower core area 240 of the core 210 such that the cooling medium introduced
around the first and second arrays 620 and 690 creates a flow that is substantially
perpendicular to the core 210 to further enhance heat dissipation from the device
600.
The core 210 has an axis 260. In some embodiments, the upper and lower
surface areas 230 and 240 are parallel to the axis 260. The core 210 further has a
base 270. In some embodiments, the base 270 is disposed such a way that it is in
close proximity to the lower surface area 240 and perpendicular to the axis 260.

The upper and lower surface areas 230 and 240 can be concentric to the axis 260.
The first array 620 is thermally coupled to the upper surface area 230 such
that components can be mounted around and in close proximity to the lower
surface area 240 and below the first array 620 when the device 600 is mounted
onto the integrated circuit device. In some embodiments, the components can
encroach onto the integrated circuit device without mechanically interfering with
the device 600.
The core 210 can be a solid body. The solid body can be cylindrical,
conical, square, rectangular, or any other similar shape that facilitates in
mounting onto the integrated circuit device and in attaching the first array 620 to
the upper surface area 230. The core 210 can include heat transport mediums
such as one or more heat pipes, a liquid, a thermo-siphon, or other such heat
transport medium that enhance beat dissipation from the integrated circuit device.
The first array 620 has a first outer diameter 250 and the second array 690
has a second outer diameter 255. The second outer diameter 255 is less than the
first outer diameter 250. The first array 620 has a first depth and the second array
690 has a second depth. The first and second outer diameters 250 and 255,
including the first and second depths, are of sufficient size to allow components
to be mounted around and in close proximity to the integrated circuit device when
the device is mounted on the integrated circuit device.
The second array 690 is thermally coupled to the lower core area 240 of the
core 210 such that the cooling medium introduced creates an omni-directional
flow around the upper and lower surface areas 230 and 240 of the core 210 and
the first and second arrays 620 and 690 to enhance heat dissipation from the
device 600. The device 600, including the core 210 and the first and second
arrays 620 and 690, can be made from materials such as aluminum, copper, or
any other materials that are capable of dissipating heat away from the integrated
circuit device. The first and second arrays 620 and 690 can be formed to have
outer shapes such as circular, square, rectangular, elliptical, conical or any other
shape suitable for allowing components to encroach around and in close
proximity to the first and second arrays 620 and 690.
Figure 7 is an isometric view 700 showing the enhanced heat dissipation
device 600 shown in Figure 6, attached to the microprocessor 120 on an
assembled motherboard 130. In the example embodiment shown in Figure 7, the
microprocessor 120 has a front side 340 and a back side 330. The front side 340
is disposed across from the back side 330. The front side 340 is attached to the
assembled motherboard 130 that has components such as low-cost capacitors 140

and other such electrical components. The base 270 shown in Figure 6, of the
enhanced heat dissipation device 600 attached to the back side 330 of the
microprocessor 120. It can be seen from Figure 7 that the first and second arrays
620 and 690 are of sufficient size so as to allow low-cost capacitors 140 mounted
on the assembled board 130 to encroach around the microprocessor 120. It can
also be seen that low-cost capacitors 140 are below the first array 620 and around
the second array 690.
Also, it can be seen in Figure 7 that the first array 620 is larger than the
second array 690, thereby increasing the heat dissipation rate without increasing
the footprint size of the base 270 of the heat dissipation device 200 any more than
the back side 330 of the microprocessor 120. The coinciding footprint sizes of the
base 270 of the heat dissipation device 200 and the back side 330 of the
microprocessor 120 enables the base 270 and the back side 330 of the
microprocessor 120 to have the same heat transfer rates. This in turn increases the
efficiency of heat transfer between the base 270 and the back side 330 of the
microprocessor 120.
A heat transport medium can be disposed around the device 600 to
introduce a heat transfer medium 297 such as air in a direction shown in Figure 6,
to create a flow that is substantially perpendicular to the core 210. Further, the
flow is substantially parallel to the first and second arrays 620 and 690 to
enhance the heat dissipation by the heat dissipation device 600. A heat transport
medium 295 such as a heat pipe, or other such medium can be included in the
core 210 to further enhance the heat transfer from the heat dissipation device 600.
In some embodiments, the enhanced heat dissipation device 600 is made of
thermally conductive materials such as copper, aluminum, or any other such
material capable of extracting heat away from the integrated circuit device. In
some embodiments, the core 210 can include heat transport mediums such as one
or more heat pipes, a liquid, a thermo-siphon, or other similar heat transport
medium suitable for enhancing the extraction of heat from the integrated circuit
device. In some embodiments, the first and second arrays 620 and 690 occupy a
first and second volume of space around the upper and lower surface areas 230
and 240 such that the first volume is less than the second volume to permit
components to be mounted on the circuit board 130 and below the first array 620
Conclusion
The above-described device and method provides, among other things,
enhanced heat dissipation by using an array of radially extending fin structures

where possible. This allows electronic components to encroach around an
integrated circuit device on which it is mounted, while maintaining high
performance and cost effectiveness by leveraging currently enabled high volume
manufacturing techniques

WE CLAIM :
1. A heat dissipation device comprising :
a thermally conductive core, wherein the core has an axis, wherein the core
has a base to mount upon an integrated circuit device, wherein the base is
perpendicular to the axis, and wherein the core has upper and lower outer
surface areas concentric to the axis and having first and second lengths,
respectively;
a first array of radially extending fin structures, the first array being thermally
coupled to the upper outer surface area along the first length, wherein the first
array has a first outer diameter; and
a second array of radially extending fin structures, the second array being
thermally coupled to the lower outer surface area along the second length,
wherein the second array has a second outer diameter, the second outer
diameter being less than the first outer diameter, and wherein the second
length and the second outer diameter are sized to provide sufficient space
below the first array to allow components to be mounted around and in close
proximity to the lower outer surface area and below the first array when the
base of the heat dissipation device is mounted on an integrated circuit device.
2. The heat dissipation device as claimed in claim 1, wherein the upper and
lower outer surface areas are parallel to the axis.
3. The heat dissipation device as claimed in claim 1, wherein the fin structures of
the first and second arrays have a cross-section from the group consisting of
square and rectangular.
4. The heat dissipation device as claimed in claim 1, wherein the core has a
shape from the group consisting of cylindrical, conical, square, and
rectangular.

5. The heat dissipation device as claimed in claim 1, wherein the core comprises
a heat transport medium.
6. The heat dissipation device as claimed in claim 1, wherein the fin structures of
the first and second arrays are perpendicular to the core.
7. The heat dissipation device as claimed in claim 1, wherein the second array
has a size sufficient to allow components to be mounted around and in close
proximity to the second array and below the first array when the heat
dissipation device is mounted on an integrated circuit device.
8. The heat dissipation device as claimed in claim 1, wherein the first and
second arrays have respective outer shapes from the group consisting of
circular, square, rectangular, elliptical, and conical.
9. The heat dissipation device as claimed in claim 1, wherein the core and the
first and second arrays comprise materials from the group consisting of
aluminum and copper.
10. The heat dissipation device as claimed in claim 1, wherein the fin structures of
the first and second arrays are from the group consisting of pin fin structures
and planar fin structures.
11. A heat dissipation system comprising :
an integrated circuit device having a gont side and a back side opposite the
front side, whereih the front sloe is attached to a surface of a circuit board, the
surface of the circuit board having components mounted thereon and
projecting outwardly from.the Surface ; and

a heat dissipation device comprising :
a thermally conductive core having a base thermally coupled to the back side
of the integrated circuit device, the core having an axis perpendicular to the
base, and the core further having upper and lower outer surface areas
concentric to the axis and having first and second lengths, respectively ;
a first array of radially extending fin structures, the first array being thermally
coupled to the upper outer surface area along the first length, wherein the first
array has a first outer diameter; and
a second array of radially extending fin structures, the second array being
thermally coupled to the lower outer surface area along the second length,
wherein the second array has a second outer diameter, the second outer
diameter being less than the first outer diameter, and wherein the second
length and the second outer diameter are sized to provide sufficient space for
the components around and in close proximity to the lower outer surface area
and below the first array.
12. The heat dissipation system as claimed in claim 11, wherein the base is in
close proximity to the lower outer surface area, and wherein the back side of
the integrated circuit device and the base have coinciding footprint sizes.
13. The heat dissipation system as claimed in claim 11, and comprising :
a heat transport medium, wherein the core has a top surface opposite the
base and in close proximity to the upper outer surface area, and wherein the
heat transport medium is coupled to the top surface.
14. The heat dissipation system as claimed in claim 11, wherein the fin structures
of the first and second arrays have a cross-section from the group consisting
of square and rectangular.

15. The heat dissipation system as claimed in claim 11, wherein the integrated
circuit device is a microprocessor.
16. The heat dissipation system as claimed in claim 11, wherein the upper and
lower outer surface areas are parallel to the axis.
17. The heat dissipation system as claimed in claim 11, wherein the core has a
shape from the group consisting of cylindrical, conical, square, and
rectangular.
18. The heat dissipation system as claimed in claim 11, wherein the fin structures
of the first and second arrays are perpendicular to the core.
19. The heat dissipation system as claimed in claim 11, wherein the second array
has a size sufficient to provide sufficient space for the components around
and in close proximity to the second array and below the first array.
20. The heat dissipation system as claimed in claim 11, wherein the first and
second arrays have respectively outer shapes from the group consisting of
circular, square, rectangular, elliptical, and conical.
21. The heat dissipation system as claimed in claim 11, wherein the core and the
first and second arrays comprise materials from the group consisting of
aluminum and copper.
22. The heat dissipation system as claimed in claim 11, wherein the fin structures
of the first and second arrays are from the group consisting of pin fin
structures and planar fin structures.

23. An article comprising :
a thermally conductive core extending upwardly from a heat producing device
mounted on a substrate ;
a first array of fin structures extending radially outwardly from an upper portion
of the core to define a first cross-sectional shape ; and
a second array of fin structures extending radially outwardly from a lower
portion of the core to define a second cross-sectional shape, wherein the area
of the second cross-sectional shape is less than the area of the first cross-
sectional shape and wherein the second cross-sectional shape is sized to
provide sufficient clearance for components mounted on the substrate around
and in close proximity to the second array of fin structures and extending
within a perimeter of the first cross-sectional shape.
24. The article as claimed in claim 23 wherein the fin structures are oriented
substantially parallel to the substrate.
25. The article as claimed in claim 23 wherein the cross-sectional shape of at
least one of the first and second arrays has a shape selected from the group
consisting of round, square, rectangular and elliptical shapes.
26. The article as claimed in claim 23 wherein the cross-sectional shape of the
core is selected from the group consisting of cylindrical, conical, square, and
rectangular shapes.
27. The article as claimed in claim 23 wherein the core comprises a heat transport
medium selected from the group consisting of heat pipes, liquids and thermo-
siphons.

28. The article as claimed in claim 23 wherein the fins of at least one of the first
and second arrays of fin structures are substantially planar and oriented with
the surface of their planes substantially perpendicular to the substrate.
29. The article as claimed in claim 23 wherein the fins of at least one of the first
and second arrays of fin structures are substantially planar and oriented with
the surface of their planes substantially parallel to the substrate.
30. The article as claimed in claim 23 wherein at least one of the core and the first
and second arrays are formed from materials selected from the group
consisting of aluminium and copper.
31. A system comprising :
a heat producing device mounted on a circuit board having outwardly
projecting components mounted thereon ;
a heat dissipation device comprising
a thermally conductive core coupled to and extending upwardly from the heat
producing device ;
a first array of fin structures extending radially outwardly from an upper portion
of the core to define a first cross-sectional shape ; and
a second array of fin structures extending radially outwardly from a lower
portion of the core to define a second cross-sectional shape, wherein the area
of the second cross-sectional shape is less than the area of the first cross-
sectional shape and wherein the second cross-sectional shape is sized to
provide sufficient clearance for components mounted on the substrate around
and in close proximity to the second array of fin structures and extending
within a perimeter of the first cross-sectional shape.

32. The system as claimed in claim 31 wherein second array of fin structures is in
close proximity to the lower outer surface area, and wherein the surface of the
heat producing device integrated circuit device and the cross-sectional shape
of the base have coincidal footprint.
33. The system as claimed in claim 31 wherein the core comprises a heat
transport medium to be coupled to the heat producing device.
34. The heat dissipation system as claimed in claim 31 wherein the heat
producing device is an integrated circuit device.

An enhanced heat dissipation device (200, 400, 600) to extract heat from an integrated circuit (120) includes a thermally conductive core (210) having upper (230) and lower (240) outer surface areas. The device further includes a first array
(220) of radially extending pin fin structures. The first array is thermally coupled to the upper surface area such that a cooling medium introduced around the core and the first array creates an omni-directional flow around the first array and the core to enhance heat dissipation from the integrated circuit device. The core including the first array and the lower surface area are of sufficient size to allow components on a motherboard (130) to encroach onto the integrated circuit device when the heat
dissipation device is mounted onto the integrated circuit device.