U.S. patent application number 11/065438 was filed with the patent office on 2006-04-20 for heat dissipation apparatus and manufacturing method thereof.
This patent application is currently assigned to Delta Electronics, Inc.. Invention is credited to Chin-Ming Chen, Yency Chen, Chi-Feng Lin, Hsin-Chang Tsai, Horng-Jou Wang.
Application Number | 20060081360 11/065438 |
Document ID | / |
Family ID | 36179518 |
Filed Date | 2006-04-20 |
United States Patent
Application |
20060081360 |
Kind Code |
A1 |
Chen; Yency ; et
al. |
April 20, 2006 |
Heat dissipation apparatus and manufacturing method thereof
Abstract
A heat dissipation apparatus. The heat-dissipation apparatus
comprises a chamber, a working fluid, an evaporation section and a
condensing section. The chamber has an inner wall, and the working
fluid is sealed in the chamber. The evaporation section and the
condensing section are located at the inner wall. The first grooves
are disposed on the inner wall and connected to the evaporation
section and the condensing section. The working fluid is vaporized
at the evaporation section when absorbing heat from the heat source
and condenses to a liquid phase and releases the heat at the
condensing section, and the first groove provides a capillary force
to drive the working fluid from the condensing section back to the
evaporation section.
Inventors: |
Chen; Yency; (Taoyuan Hsien,
TW) ; Lin; Chi-Feng; (Taoyuan Hsien, TW) ;
Chen; Chin-Ming; (Taoyuan Hsien, TW) ; Tsai;
Hsin-Chang; (Taoyuan Hsien, TW) ; Wang;
Horng-Jou; (Taoyuan Hsien, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
Delta Electronics, Inc.
|
Family ID: |
36179518 |
Appl. No.: |
11/065438 |
Filed: |
February 25, 2005 |
Current U.S.
Class: |
165/104.26 ;
257/E23.088 |
Current CPC
Class: |
F28D 15/0266 20130101;
H01L 2924/00 20130101; H01L 23/427 20130101; F28D 15/046 20130101;
H01L 2924/0002 20130101; H01L 2924/0002 20130101; F28D 15/0233
20130101 |
Class at
Publication: |
165/104.26 |
International
Class: |
F28D 15/00 20060101
F28D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 18, 2004 |
TW |
093124814 |
Claims
1. A heat-dissipation apparatus for a heat source, comprising: a
chamber comprising an inner wall; a working fluid sealed in the
chamber; an evaporation section and a condensing section located at
the inner wall; and at least one first groove disposed on the inner
wall and connected to the evaporation section and the condensing
section, wherein the working fluid is vaporized at the evaporation
section when absorbing heat from the heat source and condenses to a
liquid phase and releases the heat at the condensing section, and
the first groove provides a capillary force to drive the working
fluid from the condensing section back to the evaporation
section.
2. The heat-dissipation apparatus as claimed in claim 1 further
comprising at least one second groove disposed on the inner wall
and connected to the first groove.
3. The heat-dissipation apparatus as claimed in claim 2, wherein
the chamber is formed by folding a base plate, and each of the
second grooves is located at a folded region of the base plate and
is relatively wider than the first groove.
4. The heat-dissipation apparatus as claimed in claim 2, wherein
the first grooves are either radially extended out from the
evaporation section or concentrically disposed and focusing on the
evaporation section, or the first grooves and the second grooves
form a grid pattern.
5. The heat-dissipation apparatus as claimed in claim 2, wherein
the evaporation section, the condensing section, the first grooves
and the second grooves are formed on the inner wall of the chamber
by a miniature molding process and the miniature molding process
includes steps of: providing a substrate; applying a pre-patterned
layer on the substrate and forming the pre-patterned layer into a
pre-patterned mold by a Micro Electro-Mechanical System (MEMS)
process; providing a pattern material to the pre-patterned mold to
form a patterned mold; and molding the base plate by the patterned
mold, such that the evaporation section, the condensing section,
the first grooves, and the second grooves are formed on the base
plate.
6. The heat-dissipation apparatus as claimed in claim 2, wherein
the evaporation section, the condensing section, the first grooves
and the second grooves are formed on the inner wall of the chamber
through a mold formed by a laser or a precision manufacturing
technique.
7. The heat-dissipation apparatus as claimed in claim 1, wherein
the first grooves are either radially extended out from the
evaporation section or concentrically disposed and focusing on the
evaporation section, or the first grooves and the second grooves
form a grid pattern.
8. The heat-dissipation apparatus as claimed in claim 1, wherein
the chamber is formed by folding a base plate, and the evaporation
section, the condensing section and the first grooves are formed on
the base plate by a miniature molding process.
9. The heat-dissipation apparatus as claimed in claim 8, wherein
the miniature molding process comprises steps of: providing a
substrate; applying a pre-patterned layer on the substrate and
forming the pre-patterned layer into a pre-patterned mold by a
Micro Electro-Mechanical System (MEMS) process; providing a pattern
material to the pre-patterned mold to form a patterned mold; and
molding the base plate by the patterned mold, such that the
evaporation section, the condensing section and the first grooves
are formed on the base plate.
10. The heat-dissipation apparatus as claimed in claim 1, wherein
the evaporation section, the condensing section and the first
grooves are formed on the inner wall of the chamber through a mold
formed by a laser or a precision manufacturing technique.
11. A method for forming the heat-dissipation apparatus, comprising
steps of: providing a base plate; forming an evaporation section, a
condensing section and at least one first groove on the base plate;
and folding the base plate into a chamber so that the evaporation
section, the condensing section and the first groove are disposed
on an inner wall of the chamber.
12. The method for forming the heat-dissipation apparatus as
claimed in claim 11 further comprising a step of forming at least
one second groove disposed on the inner wall and connected to the
first groove.
13. The method for forming the heat-dissipation apparatus as
claimed in claim 12, wherein the chamber is formed by folding the
base plate, and each of the second grooves is located at a folded
region of the base plate and is relatively wider than the first
groove.
14. The method for forming the heat-dissipation apparatus as
claimed in claim 12, wherein the first grooves are either radially
extended out from the evaporation section or concentrically
disposed and focusing on the evaporation section, or the first
grooves and the second grooves form a grid pattern.
15. The method for forming the heat-dissipation apparatus as
claimed in claim 12, wherein the evaporation section, the
condensing section, the first grooves and the second grooves are
formed on the base plate by a miniature molding process, and the
miniature molding process includes steps of: providing a substrate;
applying a pre-patterned layer on the substrate and forming the
pre-patterned layer into a pre-patterned mold by a Micro
Electro-Mechanical System (MEMS) process; providing a pattern
material to the pre-patterned mold to form a patterned mold; and
molding the base plate by the patterned mold, such that the
evaporation section, the condensing section, the first grooves and
the second grooves are formed on the base plate.
16. The method for forming the heat-dissipation apparatus as
claimed in claim 12, wherein the evaporation section, the
condensing section, the first grooves and the second grooves are
formed on the base plate through a mold formed by a laser or a
precision manufacturing technique.
17. The method for forming the heat-dissipation apparatus as
claimed in claim 11, wherein the first grooves are either radially
extended out from the evaporation section or concentrically
disposed and focusing on the evaporation section, or the first
grooves and the second grooves form a grid pattern.
18. The method for forming the heat-dissipation apparatus as
claimed in claim 11, wherein the evaporation section, the
condensing section and the first grooves are formed on the base
plate by a miniature molding process, and the miniature molding
process includes steps of: providing a substrate; applying a
pre-patterned layer on the substrate and forming the pre-patterned
layer into a pre-patterned mold by a Micro Electro-Mechanical
System (MEMS) process; providing a pattern material to the
pre-patterned mold to form a patterned mold; and molding the base
plate by the patterned mold, such that the evaporation section, the
condensing section and the first grooves are formed on the base
plate.
19. The method for forming the heat-dissipation apparatus as
claimed in claim 11, wherein the evaporation section, the
condensing section, the first grooves and the second grooves are
formed on the base plate through a mold formed by a laser or a
precision manufacturing technique.
20. The method for forming the heat-dissipation apparatus as
claimed in claim 11, wherein the step of folding the base plate
into a chamber further comprises steps of: folding the base plate
to form a pipe; sealing one end of the pipe; filling a working
fluid into the pipe and vacuuming; and sealing the other end of the
pipe.
Description
[0001] This Non-provisional application claims priority under
U.S.C..sctn. 119(a) on Patent Application No(s). 093124814 filed in
Taiwan, Republic of China on Aug. 18, 2004, the entire contents of
which are hereby incorporated by reference.
BACKGROUND
[0002] The invention relates to a heat dissipation apparatus and a
manufacturing method thereof, and in particular to a vapor chamber
and a manufacturing method thereof.
[0003] With progress in technologies, the number of transistors per
unit area in an electronic device has increased. To maintain an
effective operating temperature, additional fans and dissipation
fins are commonly deployed to expel heat to the exterior. Heat
pipes, a popular choice providing heat dissipation from a heat
source, for example, can efficiently transmit large amounts of heat
long distances from a reduced section area and minimal temperature
difference therebetween without requiring additional power
electricity or much space.
[0004] A heat pipe typically comprises a vapor chamber, a wick
structure and a working fluid. The working fluid in the chamber is
vaporized at an evaporation section as latent heat is absorbed and
then condenses to a liquid phase and releases the heat at a
condensing section as latent heat is released. Then, the liquid
working fluid at the condensing section can be driven back to the
evaporation section by the capillary force of the wick structure.
Conventionally, the wick structure can be classified into four
parts: mesh wick structure, fiber wick structure, sinter wick
structure and groove wick structure.
[0005] The groove wick structure is formed on an inner wall of the
chamber by mechanical carving. However, under the limitations of
movement of the mechanical jig, only spiral and straight grooves
can be formed on the inner wall of the vapor chamber, so that the
working fluid at the condensing section cannot be efficiently
flowed back to the evaporation section along the limitedly arranged
grooves of the wick structure. Furthermore, width of the spiral or
straight groove can only achieve about 300 .mu.m by the mechanical
process, providing insufficient capillary force so that the flow
rate of the working fluid is slow and the heat dissipation
efficiency is greatly affected.
[0006] The sinter wick structure is formed by a packed powder
sintered and shaped at a high temperature. Because the sinter wick
structure has a wick structure smaller than that of the spiral or
straight grooved wick structure, the heat dissipation efficiency of
the sinter wick structure is better than that of the groove wick
structure. However, the metallic chamber is usually softened after
an annealing process, so that it is easily deformed or cracked
under external force. Although the chamber can be thicken or
enlarged, heat dissipation efficiency is correspondingly decreased
and weight thereof increases. Thus, it is important to provide a
heat dissipation apparatus to facilitate heat dissipation
efficiency in the small-size, dense and integrated electronic
devices or circuits.
SUMMARY
[0007] The invention provides a heat-dissipation apparatus with
lightweight and good performance in heat dissipation. The
heat-dissipation apparatus includes a chamber, a working fluid, an
evaporation section and a condensing section. The working fluid is
sealed in the chamber. The evaporation section and the condensing
section are located at the inner wall of the chamber. The working
fluid is vaporized at the evaporation section when absorbing heat
from the heat source, and then condenses to a liquid phase and
releases the heat at the condensing section. At least one first
groove is on the inner wall and connected to the evaporation
section and the condensing section and providing a capillary force
to drive the working fluid from the condensing section back to the
evaporation section.
[0008] In addition, at least one second groove is disposed on the
inner wall and connected to the first groove. The chamber is formed
by folding the base plate, and the second grooves are located at a
folded region on the base plate. The second groove is relatively
wider than the first groove.
[0009] Further, the invention provides a method for manufacturing
the heat-dissipation apparatus. The method includes the steps of:
providing a base plate; forming an evaporation section, a
condensing section and at least one first groove on the base plate;
and folding the base plate into a chamber so that the evaporation
section, the condensing section and the first groove are disposed
on an inner wall of the chamber.
[0010] The first grooves are formed on the base plate by a
miniature molding process, and the miniature molding process
includes steps of: providing a substrate; applying a pre-patterned
layer on the substrate and forming the pre-patterned layer into a
pre-patterned mold by a Micro Electro-Mechanical System (MEMS)
process; providing a pattern material to the pre-patterned mold to
form a patterned mold; and molding the base plate by the patterned
mold, such that the evaporation section, the condensing section and
the first grooves are formed on the base plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention can be more fully understood by reading the
subsequent detailed description and examples with references made
to the accompanying drawings, wherein:
[0012] FIG. 1 is a schematic view shows that a heat-dissipation
apparatus according to a preferred embodiment of the invention is
used to a heat source.
[0013] FIG. 2 is a sectional view of the vapor chamber in FIG.
1.
[0014] FIG. 3A is an exploded view of the vapor chamber in FIG.
2.
[0015] FIG. 3B is a schematic view shows the vapor chamber in FIG.
3A is formed by a folded base plate.
[0016] FIGS. 4A and 4B are two schematic views of another two base
plates.
DETAILED DESCRIPTION
[0017] FIG. 1 is a schematic view shows that a heat-dissipation
apparatus according to a preferred embodiment of the invention is
used to a heat source. The heat-dissipation apparatus 10, such as a
vapor chamber or a homoeothermic chamber, can be used to a heat
source 12 such as a CPU, or an electrical component giving out
heat. A metallic bottom plate 11, typically made of copper, is
attached to the heat source 12, such that heat from the heat source
12 passes directly through the heat-dissipation apparatus 10 via
the bottom plate 11, and then is quickly removed to the
exterior.
[0018] Referring to FIG. 2, which is a sectional view of the vapor
chamber in FIG. The heat-dissipation apparatus 10, preferred a
vapor chamber, includes a working fluid, an evaporation section 21,
a condensing section 22 and a wick structure 23 formed by at least
one first miniature groove. The evaporation section 21, the
condensing section 22 and the wick structure 23 are formed on the
inner wall 24 of the vapor chamber 10. The working fluid is stored
and circulated in the sealed chamber so as to dissipate heat from a
heat source to the exterior. The working fluid is an inorganic
compound, water, alcohol, liquid metal, ketone, refrigerant, or an
organic compound.
[0019] The evaporation section 21 of the vapor chamber 10 is
preferably disposed corresponding to the heat source 12, such that
heat from the heat source 12 can be directly transmitted to the
evaporation section 21 via the bottom plate 11. The working fluid
at the evaporation section 21 is vaporized to a gaseous phase as
the working fluid absorbs heat from the heat source 12, and the
vaporized working fluid condenses to a liquid phase and releases
the heat at the condensing section 22 as latent heat thereof is
released. Then, the liquid working fluid is driven beck to the
evaporation section 21 by a capillary force of the wick structure
23.
[0020] Referring both to FIGS. 3A and 3B, FIG. 3A is an exploded
view of the vapor chamber in FIG. 2, and FIG. 3B is a schematic
view shows the vapor chamber in FIG. 3A. The manufacturing method
of the vapor chamber includes the steps as follow: Firstly, a base
plate 25 is provided and the evaporation section 21, the condensing
section 22 and the wick structure 23 are formed on the base plate
25. Then, by folding the base plate 25 and sealing two edges of the
base plate 25 by welding or other methods achieve the construction
of a pipe 26, as shown in FIG. 3B. When one end of the pipe 26 is
sealed, the pipe 26 is filled with the working fluid. After the
pipe 26 filled with the working fluid is evacuated by vacuum, the
other end of the pipe 26 is sealed to form a closed vapor chamber,
and the evaporation section 21, the condensing section 22 and the
wick structure 23 are formed on the inner wall of the vapor
chamber.
[0021] In the preferred embodiments, the evaporation section 21,
the condensing section 22 and the wick structure 23 formed on the
inner wall of the vapor chamber can be achieved either by molding
the base plate with a mold or by a miniature molding process. The
mode is made by a laser or a precision manufacturing technique. As
for the miniature molding process, it preferably includes a mold
manufacturing process and a molding process. The mold manufacturing
process includes the steps of: providing a substrate; applying a
pre-patterned layer on the substrate and forming the pre-patterned
layer into a pre-patterned mold by a Micro Electro-Mechanical
System (MEMS) process; providing a pattern material to the
pre-patterned mold to form a patterned mold; and forming the
patterned mold into a finished mold. The pattern on the finished
mold (or on the patterned mold) is opposite the geometric structure
formed on the base plate 25. Thus, by using the molding process and
the finished mold (or on the patterned mold) to mold the base plate
25, the evaporation section 21, the condensing section 22 and wick
structure 23 are formed on the base plate 25.
[0022] The wick structure 23 connects the evaporation section 21
and the condensing section 22, and provides a capillary force to
drive the liquid working fluid at the condensing section 22 back to
the evaporation section 21. It is noted that distribution of the
wick structure 23 on the inner wall of the vapor chamber, i.e. the
base plate 25, is not limited to the disclosed embodiment. In FIG.
3A, the wick structure 23 includes several straight first miniature
grooves 231a, 231b and several second miniature grooves 232. Each
second miniature groove 232 is connected with at lease two straight
first miniature grooves 231a or 231b, such that the working fluid
still can flow back to the evaporation section 21 along the
straight first miniature grooves 231b and 231a even if some of them
are blocked or malfunctioned. Furthermore, the second miniature
groove 232 is relatively wider than the straight first miniature
groove 231a or 231b. Therefore, the working fluid in the straight
first miniature groove 231b can be merged into the second miniature
groove 232 and then flow back to the evaporation section 21, so
that the flowing speed of the working fluid is improved.
[0023] Considering the construction of the vapor chamber formed by
folding the base plate 25, it is preferable to build up the second
miniature grooves 232 at a folded region of the base plate 25 to
facilitate the following process of manufacturing the pipe 26.
[0024] Further, referring to FIGS. 4A and 4B, which are two
schematic views of another two base plates. Because the wick
structure of the present invention is formed by a laser, a
precision manufacturing technique or a miniature molding process,
such that the miniature groove can be achieved substantially 100
.mu.m wide or less and thus the capillary force of the wick
structure is greatly increased. Furthermore, distribution of the
miniature grooves of the wick structure can varied corresponding to
the need of the heat source. For example, the straight first
miniature grooves 231a are radially extended out from the
evaporation section 21, as shown in FIG. 3A. Or, the first
miniature grooves 231 and the second miniature grooves 232 are
collocated to form a grid pattern on the base plate 25, as shown in
FIG. 4A. Furthermore, as shown in FIG. 4B, several annular first
miniature grooves 231c are concentrically disposed and focusing on
the evaporation section 21, and several straight first miniature
grooves 231a are radially extended out from the evaporation section
21 and intersectively and connected to the annular first miniature
grooves 231c. In addition, several second miniature grooves 232
with greater widths connect between the straight first miniature
grooves 231a and the annular first miniature grooves 231c.
[0025] Therefore, the heat-dissipation apparatus of the invention
presents a vapor chamber with lightweight and good performance in
heat dissipation. The miniature grooves formed by laser, precision
manufacturing technique or miniature molding process facilitate
efficiency of heat dissipation, and an economical material of the
vapor chamber decreases weight and cost thereof.
[0026] While the invention has been described with respect to
preferred embodiment, it is to be understood that the invention is
not limited thereto the disclosed embodiments, but, on the
contrary, is intended to accommodate various modifications and
equivalent arrangements included within the spirit and scope of the
appended claims.
* * * * *