U.S. patent application number 11/309674 was filed with the patent office on 2007-05-10 for heat dissipation apparatus and method for manufacturing the same.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to CHUN-YI CHANG.
Application Number | 20070102147 11/309674 |
Document ID | / |
Family ID | 38002571 |
Filed Date | 2007-05-10 |
United States Patent
Application |
20070102147 |
Kind Code |
A1 |
CHANG; CHUN-YI |
May 10, 2007 |
HEAT DISSIPATION APPARATUS AND METHOD FOR MANUFACTURING THE
SAME
Abstract
An exemplary heat dissipation apparatus includes a base member
and a number of cooling fins. Each of the cooling fins includes a
main part and a foot part embedded in the base member, the foot
part includes a first portion extending from the main part in the
extension direction of the main part and at least one second
portion extending at an angle from the first portion. The heat
dissipation apparatus has a high heat dissipation efficiency.
Inventors: |
CHANG; CHUN-YI;
(Tu-Cheng,Taipei Hsien, TW) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. CHENG-JU CHIANG JEFFREY T. KNAPP
458 E. LAMBERT ROAD
FULLERTON
CA
92835
US
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
66,CHUNG SHAN ROAD
Tu-Cheng
TW
|
Family ID: |
38002571 |
Appl. No.: |
11/309674 |
Filed: |
September 8, 2006 |
Current U.S.
Class: |
165/185 ;
257/E23.088 |
Current CPC
Class: |
F28F 3/02 20130101; H01L
21/4878 20130101; H01L 2924/0002 20130101; H01L 23/427 20130101;
H01L 2924/0002 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
165/185 |
International
Class: |
F28F 7/00 20060101
F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 4, 2005 |
CN |
200510101022.8 |
Claims
1. A heat dissipation apparatus comprising: a base member and a
plurality of cooling fins, each of the cooling fins comprising a
main part and a foot part embedded in the base member, the foot
part comprising a first portion extending from the main part in the
extension direction of the main part and at least one second
portion extending at an angle from the first portion.
2. The heat dissipation apparatus as claimed in claim 1, wherein
the second section extends so as to be perpendicular to the first
portion.
3. The heat dissipation apparatus as claimed in claim 1, wherein
the at least one second portion comprises two opposite second
portions extending from the first portion.
4. The heat dissipation apparatus as claimed in claim 1, wherein
the base member comprises a phase change chamber.
5. The heat dissipation apparatus as claimed in claim 4, wherein
the phase change chamber contains a cooling fluid therein.
6. The heat dissipation apparatus as claimed in claim 5, wherein
the cooling fluid is selected from the group consisting of:
ammonia, alcohol, acetone, water and any combination thereof.
7. The heat dissipation apparatus as claimed in claim 4, wherein a
pressure in the phase change chamber is in the range from 10-3 Pa
to 10-2 Pa.
8. The heat dissipation apparatus as claimed in claim 1, wherein a
material of the base member and the cooling fins is selected from
the group consisting of: copper, aluminium and copper-aluminium
alloy.
9. The heat dissipation apparatus as claimed in claim 1, wherein a
copper-aluminium alloy layer is formed between the cooling fins and
the base member.
10. A method for manufacturing a heat dissipation apparatus, the
method comprising the steps of: providing a base member and a
plurality of cooling fins each having a main part and a foot part,
the foot part comprising a first portion extending from the main
part in the extension direction of the main part and a second
portion extending at an angle from the first portion; defining a
plurality of grooves on the base member in a manner so as conform
to a shape of the foot parts of the cooling fins; and pressing the
foot parts of the cooling fins into the corresponding grooves at a
high temperature and a high pressure.
11. The method as claimed in claim 10, wherein the temperature is
in the range from 500.degree. C. to 600.degree. C.
12. The method as claimed in claim 10, wherein the pressure is in
the range from 600 to 1200 kilo-Newtons/metre2.
13. The method as claimed in claim 10, wherein the pressing step is
performed using a stamper.
14. A heat dissipation apparatus comprising: a base member
comprising a phase change member defined therein, the phase change
member containing a cooling fluid therein; and a plurality of
cooling fins extending from the base member.
15. The heat dissipation apparatus as claimed in claim 14, wherein
the cooling fluid is selected from the group consisting of:
ammonia, alcohol, acetone, water and any combination thereof.
16. The heat dissipation apparatus as claimed in claim 14, wherein
a pressure in the phase change chamber is in the range from 10-3 Pa
to 10-2 Pa.
Description
DESCRIPTION
[0001] 1. Technical Field
[0002] The present invention relates generally to heat dissipation
apparatuses and, more particularly, to a heat dissipation apparatus
having improved heat dissipation efficiency used in an electronic
device and a method for manufacturing the heat dissipation
apparatus.
[0003] 2. Discussion of Related Art
[0004] With the development of electronic science, operational
frequencies of electronic components such as CPUs have become
higher and higher, and as a result more energy is consumed and more
heat is generated. As a result, it has become necessary to use a
powerful heat dissipation device to dissipate the heat generated by
the electronic components.
[0005] A typical heat dissipation apparatus generally includes a
base and a number of cooling fins attached to the base. The base
and the cooling fins can be made of a metal having high heat
conductivity. Such metal can be, for example, copper, aluminium,
etc. Advantageously, the base is made of a highly heat-conductive
material such as copper, and the cooling fins are made of aluminium
which can be easily processed to form a variety of shapes.
[0006] Such devices are usually disposed on a heat source for
dissipating heat generated by the heat source through a combination
of heat conduction and convection. Firstly, heat generated by the
heat source is conducted to the atmosphere at a surface of the
device by conduction; secondly, the heat dissipates into atmosphere
by convection.
[0007] However the highly heat-resistant interfaces between the
base and the cooling fins make the heat resistance of the heat
dissipation apparatus relatively high, and heat dissipation
efficiency of the heat dissipation device is therefore
unsatisfactory.
[0008] Thus, there is a desire to develop a heat dissipation
apparatus that has a low heat resistance between the base and the
cooling fins, so as to improve the heat dissipation efficiency.
SUMMARY
[0009] In one embodiment, a heat dissipation apparatus includes a
base member and a number of cooling fins. Each of the cooling fins
includes a main part and a foot part embedded in the base member,
the foot part includes a first portion extending from the main part
in the extension direction of the main part (i.e., forming a
continuation of the main body) and at least one second portion
extending at an angle from the first portion.
[0010] In one embodiment, a method for manufacturing a heat
dissipation apparatus, the method comprising the steps of:
providing a base member and a plurality of cooling fins each having
a main part and a foot part, the foot part including a first
portion extending from the main part in the extension direction of
the main part and a second portion extending at an angle from the
first portion; defining a number of grooves on the base member in a
manner so as conform to a shape of the foot parts of the cooling
fins; and pressing the foot parts of the cooling fins into the
corresponding grooves at a high temperature and a high
pressure.
[0011] This and other features and advantages of the present
invention as well as the preferred embodiments thereof and a heat
dissipation apparatus and techniques for fabricating heat
dissipation apparatus in accordance with the invention will become
apparent from the following detailed description and the
descriptions of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Many aspects of the present apparatus and method can be
better understood with reference to the following drawings. The
components in the drawings are not necessarily drawn to scale, the
emphasis instead being placed upon clearly illustrating the
principles of the present apparatus and method. Moreover, in the
drawings, like reference numerals designate corresponding parts
throughout the several views
[0013] FIG. 1 is a schematic, cross sectional schematic view of a
heat dissipation apparatus in accordance with a first preferred
embodiment;
[0014] FIG. 2 is a schematic, cross sectional view of the heat
dissipation apparatus disposed on a heat source;
[0015] FIG. 3 is a schematic, cross sectional view of a heat
dissipation apparatus in accordance with a second preferred
embodiment;
[0016] FIG. 4 is a schematic, cross sectional view of a heat
dissipation apparatus in accordance with a third preferred
embodiment;
[0017] FIG. 5 is a schematic, cross sectional view of a heat
dissipation apparatus in accordance with a fourth preferred
embodiment;
[0018] FIG. 6 is a flow chart of a method for manufacturing a heat
dissipation apparatus in accordance with another preferred
embodiment; and
[0019] FIG. 7 is a schematic, cross sectional view of a base member
for manufacturing the heat dissipation apparatus.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] Referring now to FIG. 1, a heat dissipation apparatus 10 in
accordance with the first preferred embodiment includes a base
member 12 and a number of cooling fins 14. Each of the cooling fins
14 includes a main part 141 and a foot part 142 embedded in the
base member 12 by using a process such as, for example, hot
pressing and metallurgical means. such as, for example, placing the
cooling fins 14 in liquid metal and then cooling the liquid to form
the base member 12 with the cooling fins 14 embedded therein. Each
foot part 142 includes a first portion 143 and a second portion
144. The first portion 143 extends straightly from the main part
141 along a longitudinal extension direction of the main part 141.
The second portion 144 extends at an angle from the first portion
143. Thus, the first portion 143 and the second portion 144 form an
obtuse angle to each other. The base member 12 and the cooling fins
14 are made of a metal or an alloy having high heat conductivity,
such as copper, aluminium or copper-aluminium alloy.
[0021] Referring to FIG. 2, the heat dissipation apparatus 10 can
be used for dissipating heat from a heat source 16. The heat source
16 is an electronic component such as a microprocessor. When the
heat dissipation apparatus 10 is disposed on the heat source 16,
heat generated in the heat source 16 is conducted to the main part
141 of the heat dissipation apparatus 10 through the foot part 142
and is dispersed into the ambient air. In the preferred embodiment,
that the foot part 142 is inserted into the base member 12 using a
process such as, for example, hot pressing, improves a contact area
between the base member 12 and the foot part 142, and heat
resistance between the base member 12 and the foot part 142 is
decreased as a result.
[0022] Referring to FIG. 3, a heat dissipation apparatus 20 in
accordance with a second embodiment is similar to that of the first
embodiment except that each foot part 242 is composed of a first
portion 243 and a second portion 244 extending perpendicularly to
the first portion 243 so as to form "L" shaped cooling fins.
[0023] Referring to FIG. 4, a heat dissipation apparatus 30 in
accordance with a third embodiment is similar to that of the first
embodiment except that each foot part 342 includes a first portion
343 and a second portion 344 perpendicular to the first portion
343. The first portion 343 of each foot part 342 is connected to a
center of the second portion 344 so as to form inverted "T" shaped
cooling fins.
[0024] Referring to FIG. 5, the heat dissipation apparatus 40 in
accordance with a fifth embodiment shown is similar to that of the
second embodiment except that a base member 42 defines a vapor
chamber 422 therein and a number of cooling fins 44 extending from
the base member with a portion of each cooling fin being embedded
in an upper portion of the base member 42 using a process such as,
for example, hot pressing. The vapor chamber 422 contains a fluid
424 for facilitating heat conduction evenly from the base member 42
to the cooling fins 44. The fluid 424 can be a low boiling point
fluid such as alcohol, acetone and ammonia, a high boiling point
fluid such as water or any combination thereof. In order to
decrease the boiling point of the fluid 424, the vapor chamber 422
should preferably be vacuumized to a pressure in the range from
10-3 Pa to 10-2 Pa.
[0025] In use, the base member 42 works as a heat pipe, i.e., the
fluid 424 in the vapor chamber 422 is vaporized after absorbing
heat generated from a heat source (not shown), the vapor flows from
one end of the vapor chamber 422 to another end and discharges heat
quickly. Thus, the heat is evenly transferred to the upper portion
of the base member 42 and is conducted to the cooling fins 44
uniformly.
[0026] The heat dissipation apparatus in accordance with the
aforementioned embodiments can be made by the following method.
Take the heat dissipation apparatus 20 for example, referring to
FIG. 6 and FIG. 7, the method includes the steps of: [0027] Step 1,
providing a base member and a number of cooling fins each having a
foot part 242 at an extremity thereof, wherein the foot part 242
includes a first portion 243 and a second portion 244 perpendicular
to the first portion 242; [0028] Step 2, defining a number of
grooves on the base member in a manner so as conform to a shape of
the foot part 242 of the cooling fins; and [0029] Step 3, pressing
the foot parts 242 of the cooling fins into the grooves 222 at a
high temperature and a high pressure.
[0030] In step 1, each of the cooling fins includes a main part
extending from the first portion of the foot part. The base member
and the cooling fins are made of a material having high heat
conductivity such as copper, aluminium, or copper-aluminium
alloy.
[0031] In step 2, the grooves are configured for receiving the foot
part 242. In order to increase the contact area between the foot
parts 242 and the base member, the grooves are shaped so as to
tightly accommodate the foot parts 242. Referring now to FIG. 7,
each of the grooves 222 includes a first space 224 and a second
space 226. The first space 224 is used for receiving the first
potion 243. The second space 226 is used for receiving the second
portion 244. The grooves 222 can be made by cutting or
electrostatic discharging process. A size of the grooves should be
less than that of the foot part 242, and preferably the size of the
grooves should be approximately 0.2% to 5% less than that of the
foot part 242.
[0032] In step 3, the temperature can be in a range from 500 to 600
degrees Celsius. Preferably, the pressure should be in the range
from 600 to 1200 kilo-Newtons/metre2. This step can be performed by
stamping/pressing. That is, the cooling fins 54 can be stamped into
the grooves from the side surface of the base member 52 using a
stamper. At such a high temperature and under such a high pressure,
the atoms on the surface of the cooling fins and the grooves mix
across the gap between the cooling fins and the grooves thus form
an copper-aluminium alloy layer between the base member and the
cooling fins.
[0033] The heat dissipation apparatus 20 can also be manufactured
by using a metallurgical means, such as, for example, melting a
metal material of the base member to a liquid in a mold and then
inserting the cooling fins into the liquid, cooling the liquid and
the cooling fins thereby obtaining the heat dissipation apparatus
20. Alternatively, a number of grooves are formed on the base
member in a manner so as conform to a shape of the foot part 242 of
the cooling fins, a mold is disposed on the base member, the mold
and the grooves cooperatively define a number of chambers having
the shape of the cooling fins, then a liquid of the metal material
of the cooling fins is placed in the chambers, when the liquid is
cooled the heat dissipation apparatus 20 is obtained.
[0034] Finally, it is to be understood that the above-described
embodiments are intended to illustrate rather than limit the
invention. Variations may be made to the embodiments without
departing from the spirit of the invention as claimed. The
above-described embodiments illustrate the scope of the invention
but do not restrict the scope of the invention.
* * * * *