U.S. patent application number 11/221791 was filed with the patent office on 2006-07-20 for cooling structure of solid state and formation thereof with integrated package.
This patent application is currently assigned to INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE. Invention is credited to Jen-Hau Cheng, Chun-Kai Liu.
Application Number | 20060156737 11/221791 |
Document ID | / |
Family ID | 36682427 |
Filed Date | 2006-07-20 |
United States Patent
Application |
20060156737 |
Kind Code |
A1 |
Liu; Chun-Kai ; et
al. |
July 20, 2006 |
Cooling structure of solid state and formation thereof with
integrated package
Abstract
A cooling structure of solid state applied to a heat source has
a module of thermoelectric transfer and a module of thermo transfer
including two structures of passive cooling connected and attached
the module of thermoelectric transfer, respectively. One structure
of first structure of passive cooling is near heat source and heat
generated by the heat source is transferred to another structure of
passive cooling through the one structure passive cooling and the
module of thermoelectric transfer when electrical power is employed
to the module of thermoelectric transfer.
Inventors: |
Liu; Chun-Kai; (Taipei City,
TW) ; Cheng; Jen-Hau; (Taipei City, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
INDUSTRIAL TECHNOLOGY RESEARCH
INSTITUTE
|
Family ID: |
36682427 |
Appl. No.: |
11/221791 |
Filed: |
September 9, 2005 |
Current U.S.
Class: |
62/3.2 ;
257/E23.082; 257/E23.092; 62/3.7 |
Current CPC
Class: |
F25B 21/02 20130101;
H01L 2224/48247 20130101; H01L 2924/181 20130101; H01L 2924/16152
20130101; H01L 2924/15311 20130101; H01L 2224/48091 20130101; H01L
24/48 20130101; H01L 2924/00014 20130101; H01L 2924/207 20130101;
H01L 2224/45015 20130101; H01L 2924/00014 20130101; H01L 2224/45099
20130101; H01L 2924/00012 20130101; H01L 2924/01078 20130101; H01L
23/38 20130101; H01L 2224/48091 20130101; F25B 2321/023 20130101;
H01L 2924/181 20130101; H01L 2924/1517 20130101; H01L 2924/1532
20130101; H01L 2924/00014 20130101; H01L 23/3128 20130101; H01L
2924/15153 20130101; H01L 23/4334 20130101; H01L 2924/00014
20130101 |
Class at
Publication: |
062/003.2 ;
062/003.7 |
International
Class: |
F25B 21/02 20060101
F25B021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 14, 2005 |
TW |
94101165 |
Claims
1. A cooling structure of solid state, applied to a heat source,
said cooling structure of solid state comprising: a module of
thermoelectric transfer; and a module of thermal transfer including
a first structure of passive cooling and a second structure of
passive cooling connected and attached said module of
thermoelectric transfer, respectively, said first structure of
passive cooling near said heat source; wherein heat generated by
said heat source is transferred to said second structure of passive
cooling through said first structure of passive cooling and said
module of thermoelectric transfer when electric power is employed
to said module of thermoelectric transfer.
2. The cooling structure of solid state according to claim 1,
wherein said module of thermoelectric transfer comprises a
plurality of thermoelectric elements and conductive junctions, a
portion of said conductive junctions configured for connecting any
two said thermoelectric elements neighboring each other and said
heat source.
3. The cooling structure of solid state according to claim 2,
wherein said plurality of thermoelectric elements are made of
N-type and P-type semiconductor materials.
4. The cooling structure of solid state according to claim 1,
wherein said first structure of passive cooling comprises a part of
thermal conduction and a part of electro insulation between said
module of thermoelectric transfer and said part of thermal
conduction.
5. The cooling structure of solid state according to claim 4,
wherein said part of electro insulation is implemented by
electroplating, coating, sputtering or sintering. a ceramic
material, oxide layer or electrical insulator.
6. The cooling structure of solid state according to claim 1,
wherein said second structure of passive cooling comprises a part
of thermal conduction and a part of electrical insulation between
said module of thermoelectric transfer and said part of thermal
conduction.
7. The cooling structure of solid state according to claim 6,
wherein said part of electro insulation is implemented by
electro-plating, coating, sputtering or sintering a ceramic
material, oxide layer or electrical insulator.
8. A package system of integrating package and cooling structure,
comprising: a package module including a heat source; a module of
thermoelectric transfer; and a module of thermal transfer including
a first structure of passive cooling and a second structure of
passive cooling connected and attached said module of
thermoelectric transfer, respectively, said first structure of
passive cooling near said heat source; wherein heat generated by
said heat source is transferred to said second structure of passive
cooling through said first structure of passive cooling and said
module of thermoelectric transfer when electrical power is employed
to said module of thermoelectric transfer.
9. The package system of integrating package and cooling structure
according to claim 8, wherein said package module further comprises
an electric circuit board, a plurality of conductive junctions and
a molding compound, said heat source on a surface of said printed
circuit board, said plurality of conductive junctions electrically
connecting said electric circuit board and said heat source, and
said molding compound on a portion of said surface, said heat
source and said plurality of conductive junctions.
10. The package system of integrating package and cooling structure
according to claim 8, wherein said package module further comprises
a lead-frame, a plurality of structures of conductive connection
and a molding compound, said plurality of structure of conductive
connection electrically connecting a plurality of inner leads of
said lead-frame and said heat source, said molding compound
encapsulating said plurality of inner leads, said heat source and
said plurality of structures of conductive connection.
11. The package system of integrating package and cooling structure
according to claim 8, wherein said module of thermoelectric
transfer comprises a plurality of thermoelectric elements and
conductive junctions, a portion of said conductive junctions
configured for connecting any two said thermoelectric elements
neighboring each other and said heat source.
12. The package system of integrating package and cooling structure
according to claim 8, wherein said first structure of passive
cooling is a metallic heat sink with a sintered surface near said
module of thermoelectric transfer.
13. The package system of integrating package and cooling structure
according to claim 8, wherein said second structure of passive
cooling comprises a part of thermal conduction and a part of
electrical insulation between said module of thermoelectric
transfer and said part of thermal conduction.
14. The package system of integrating package and cooling structure
according to claim 8, wherein said second structure of passive
cooling comprises a metallic substrate, said metallic substrate
with a sintered surface near said module of thermoelectric transfer
on one side and a plurality of metallic heat fins on the other
side.
15. A method of forming cooling structure of solid state,
comprising: providing a first structure of passive cooling and a
plurality of first adhesion structure on a first surface of said
first structure of passive cooling; positioning a plurality of
structure of thermoelectric transfer on said first surface, wherein
each of said structures of thermoelectric transfer is associated
with each of said first adhesion structures; providing a second
structure of passive cooling and a plurality of second adhesion
structure on a second surface of said second structure of passive
cooling; and attaching each of said structures of thermoelectric
transfer to each of said second adhesion structures.
16. The method of forming cooling structure of solid state
according to claim 15, wherein the step of providing said first
structure of passive cooling comprises: providing a thermal
conductive substrate providing said first surface; forming a
plurality of metallic structure positioned on said first surface;
and forming a conductive bump on each of said metallic structures,
wherein each of said first adhesion structures comprises said
conductive bump and said associated metallic structure.
17. The method of forming cooling structure of solid state
according to claim 16, wherein the step of forming said conductive
bump is implemented by printing.
18. The method of forming cooling structure of solid state
according to claim 15, wherein the step of positioning comprises:
forming a plurality of first conductive junctions on said first
surface; forming a plurality of thermoelectric elements on said
plurality of first conductive junctions; and forming a plurality of
second conductive junctions on said plurality of thermoelectric
elements, wherein any two said thermoelectric elements neighboring
each other connect through one of any said first conductive
junction and any said second conductive junction.
19. The method of forming cooling structure of solid state
according to claim 15, wherein the step of said second structure of
passive cooling comprises: providing a thermal conductive substrate
providing said second surface; forming a plurality of metallic
structure positioned on said second surface; and forming a
conductive bump on each of said metallic structures, wherein each
of said second adhesion structures comprises said conductive bump
and said associated metallic structure.
20. The method of forming cooling structure of solid state
according to claim 19, further comprising sintering said second
surface.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to the cooling structure of
solid state, the formation and application thereof. More
specifically, this invention relates to the cooling structure of
solid state in combination the structures of active and passive
cooling, the formation and application thereof.
[0003] 2. Description of the Prior Art
[0004] With the development of high integrality for electric
products, the issue about heat dissipation from CPU, LD or power
transistor becomes more and more important. Cooling device of solid
state is mostly used because of its high cooling power and low
cooling temperature.
[0005] Generally, the cooling modules for the cooling device of
solid state include the types of passive cooling and active
cooling. A heat sink, with passive cooling, dissipates heat when
itself is in temperature higher than an environment. Oppositely, a
thermoelectric cooler, with active cooling, dissipates heat even
the temperature itself is lower than the environment. The structure
of thermoelectric cooler is advantageous without pollution and
noise, and with compact and light volume.
[0006] For example, the known system of heat dissipation for the
package structure of IC has thermoelectric device with
predetermined size and shape associated with heat sink. However, on
consideration of the variety of the package structures of IC, the
end product of thermoelectric device restricts the selectivity for
heat sink. Furthermore, the easy assembly and use for the
dissipation elements would be considered for selecting the system
of heat dissipation. For example, the mechanical intensities of
conventional thermoelectric material are susceptible to crack and
break when attached or used. Furthermore, the interfaces of hereto
materials among the thermoelectric material, heat sink and package
structure of IC leading to much thermal resistance. Once the
existence of the more and more interfaces of hereto materials, the
dissipation effect could be down. Furthermore, the done
thermoelectric device and heat sink assembled to the package
structure of IC increase the volume of a whole package.
SUMMARY OF THE INVENTION
[0007] To resolve the issue of heat dissipation caused by the
interface of hereto materials, the structure of solid state in
combination structures of active and passive cooling is provided
herein. The structure of active cooling is directly formed or
combined on the one of passive cooling during the formation of the
structure of passive cooling to reduce the formation of hereto
surface that causes the poor heat dissipation and transference.
[0008] To reduce the size of an electrical device on consideration
of heat dissipation, the structure of solid state in combination of
active and passive cooling is provided herein. The cooling
structure is directly applied to single electronics device, such as
the package structure of IC, without the addition of assembly or
fixture.
[0009] Accordingly, a cooling structure of solid state applied to a
heat source has a module of thermoelectric transfer and a module of
thermal transfer including a first structure of passive cooling and
a second structure of passive cooling connected and attached the
module of thermoelectric transfer, respectively. The structure of
first structure of passive cooling is near heat source and heat
generated by the heat source is transferred to the structure of
second structure of passive cooling through the structure of first
structure of passive cooling and the module of thermoelectric
transfer when electrical power is employed to the module of
thermoelectric transfer.
[0010] Accordingly, a method of forming cooling structure of solid
state is provided. A plurality of first adhesion structures are on
the first surface of a first structure of passive cooling. A
plurality of thermoelectric transfer structures are positioned on
the first surface. Each plurality of thermoelectric transfer
structures is associated with each of the first adhesion
structures. A plurality of second adhesion structures are on the
second surface of a second structure of passive cooling. Each the
plurality of thermoelectric transfer structures is attached to each
of the second adhesion structures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] These and other objects and advantages of the present
invention will become more fully apparent from the following
detailed description when read in conjunction with the accompanying
drawings with like reference numerals indicating corresponding
parts throughout, wherein:
[0012] FIG. 1 is a schematically side diagram illustrating a
structure of active cooling in accordance with one embodiment of
the present invention.
[0013] FIG. 2 is a side-sectional diagram illustrating a cooling
structure of solid state in accordance with one embodiment of the
present invention.
[0014] FIG. 3A is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a package of wire bond in
accordance with the present invention.
[0015] FIG. 3B is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a package of cavity-down in
accordance with the present invention.
[0016] FIG. 3C is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a lead-frame package in
accordance with the present invention.
[0017] FIG. 3D is a cross-sectional diagram illustrating a cooling
structure of solid state applied to multi-chip package in
accordance with the present invention.
[0018] FIG. 4A to FIG. 4D is a cross-sectional diagrams
illustrating a cooling structure of solid state integrated to a
package structure of wire bond in accordance with the present
invention.
[0019] FIG. 5A to FIG. 5D are schematically cross-sectional
diagrams illustrating an exemplary cooling structure of solid state
integrated into a package structure of wire bond in accordance with
the present.
[0020] FIG. 6 is a schematically cross-sectional diagram
illustrating the cooling structure combined with a molding frame in
accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] Reference is now made in detail to specific embodiments of
the present invention that illustrate the best mode presently
contemplated by the inventors for practicing the invention. It
should be understood that the description of the best mode is
merely illustrative and that it should not be taken in a limiting
sense.
[0022] FIG. 1 is a schematically side diagram illustrating a
structure of active cooling in accordance with one embodiment of
the present invention. For simplification, the structure of active
cooling 10 is repeatedly shown in the following drawings without
detail. In fact, the structures of active cooling 10 in other
drawings are identical to the one in FIG. 1.
[0023] Referring to FIG. 1, the structure of active cooling 10,
such as a module of thermoelectric transfer, mainly includes
thermoelectric elements 11a, 11b, and conductive junction 12 on the
ends of the thermoelectric elements 11a, 11b. The conductive
junction 12a is on the end of the thermoelectric element 11a, as
well as the conductive junction 12b on the end of the
thermoelectric element 11b. The conductive junctions 12a and 12b
are on the same side but not connected with each other. The
conductive junction 12 is positioned on the other end of the
thermoelectric element 11a and parallel to thermoelectric element
11b. In one embodiment, on one hand the conductive junctions 12a
and 12b connect with an exterior electrical power output or
electrical power input 14, and on the other hand each conductive
junction 12a or 12b connects with one end of the thermoelectric
element 11b or thermoelectric element 11a of the other structure of
active cooling 10. That is, the two structure of active cooling 10
neighbor each other share the conductive junction 12a or 12b.
Furthermore, the conductive junction 12, conductive junction 12a or
12b is substantially vertical to the thermoelectric elements 11a
and 11b.
[0024] In one embodiment, each thermoelectric elements 11a and 11b
constitute a pair of thermoelectric couple, and are made of the
materials with the different conductivities. For example, but not
limited to, on one hand the thermoelectric element 11a is made of
P-type semiconductor material of bismuth/telluric alloy for
providing electrical holes, and on the other hand the
thermoelectric element 11b is made of N-type semiconductor material
of bismuth/telluric alloy for providing electrons. Furthermore, the
conductive junctions 12a, 12b and conductive junction 12, such as
consisted of a layer of conductive connection 8 and an adhesive
layer of solder paste 9, is used as the electrodes of the
thermoelectric elements 11a and 11b, is attached to the
thermoelectric elements 11a and 11b. With the connection of the
conductive junctions 12a, 12b and conductive junction 12, the
thermoelectric elements 11a and 11b are electrical in series but
thermal in parallel.
[0025] FIG. 2 is a side-sectional diagram illustrating a cooling
structure of solid state in accordance with one embodiment of the
present invention. A cooling structure of solid state 20 includes a
module of thermal transfer, such as two structures of passive
cooling 22a and 22b in parallel and one or more structures of
active cooling 10 is positioned between the structures of passive
cooling 22a and 22b. The parts of structures of passive cooling 22a
and 22b near the structure of active cooling 10 support the
structure of active cooling 10 and are electrically insulating from
the structure of active cooling 10. In the embodiment, the
structures of passive cooling 22a and 22b are made of the materials
with both good thermal and electrical conductivities, such as
copper or aluminum metal or alloy. Furthermore, the interface
between the structure of passive cooling 22a or 22b and the
structure of active cooling 10 would be processed to be
electrically insulating. Different from a conventional cooling
device of solid state with a ceramic substrate, one of features of
the present invention provides the structure of active cooling 10
in combination of the structures of passive cooling 22a and 22b,
which reduces thermo resistance because of a hetero-interface.
Moreover, the structures of passive cooling 22a and 22b is made of
metal, alloy or semiconductor based materials, are with the thermal
conductivities better than the conventional ceramic substrate, so
as to improve heat dissipation.
[0026] It is noted that a layer of electrical insulation is just
used for insulation rather than supporting even though the layer of
electrical insulation is formed by processing the interface between
the structure of passive cooling 22a or 22b and the structure of
active cooling 10, so the thermal resistance for the layer of
electrical insulation with the minute thickness would be
neglected.
[0027] In the embodiment, the structure of passive cooling 22a,
such as a plurality of fins 23 in parallel, are isolated from each
another but connected with a backplate 24. One side of the
structure of passive cooling 22a are attached to the structure of
active cooling 10 and used for a heat sink, extract heat from the
structure of active cooling 10 and drain the heat out of the other
side of the structure of passive cooling 22a. Furthermore, the heat
fins 23 would be with any suitable shape, such as plate, column or
cube. Moreover, the pitch between any neighbor two heat fins 23,
the amount and length are adjustable.
[0028] Next, the structure of passive cooling 22b, such as a heat
spreader, has one side attached and connected to the structure of
active cooling 10, and the other side near a heat source for
receiving heat generated from the heat source and transferring the
heat to the structure of active cooling 10. Similar to the
structure of passive cooling 22a, the structure of passive cooling
22b would be with any suitable shape, such as plate, column or
cube. Moreover, the pitch between any neighbor two heat fins 23,
the amount and length are adjustable. In accordance with the
present invention, the cooling structure of solid state 20, which
has the structures of passive cooling 22a and 22b in combination of
the structure of active cooling 10 with any amount, size, and
configuration, are variable for any requirement, especially for a
package design. Thus, different from a conventional package with a
post-formed additional heat device, in the embodiment of the
present invention, a thermoelectric module is directly formed under
the heat fins, rather than the addition of thermoelectric materials
both on a device and under the heat fins. Such a structure would
dissipate rapidly the heat from a chip, reduce both thermal
resistance and volume and provides a design of heat dissipation
with low cost and little complexity.
[0029] FIG. 3A to FIG. 3D are cross-sectional diagrams illustrating
a cooling structure of solid state applied to a conventional
package structure. It is noted that the exemplary package structure
is applied to not only the following type but also a dual in-line
package (DIP), flat package (FP), pin grid array (PGA) or ball grid
array (BGA). Especially, the embodiment illustrated with a single
chip is also applied to other packages of stack-chip or multichip
sets.
[0030] FIG. 3A is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a package of wire bond in
accordance with the present invention. The heat source 30, such as
a chip in operation, is attached on a print circuit board 32 and
connected to one bonding pad (not shown) on the surface of the
print circuit board 32 with conductive wires 35, so as to
electrically connect with the heat source 30 and the print circuit
board 32. The print circuit board 32 also includes other conductive
structures 33, such as solder balls, positioned on the other
surface of the print circuit board 32 for the electrical connection
with an exterior device. The exemplary cooling structure of solid
state 20 is overlaid on the heat source 30. With any suitable
method, such as molding compound is overlaid on the structure of
passive cooling 22b of the cooling structure of solid state 20 for
attaching the cooling structure of solid state 20. Such as a
cooling structure of solid state 20 applied to a package structure
of wire bond is beneficial for the design of heat sink for the
whole package structure.
[0031] FIG. 3B is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a package of cavity-down in
accordance with the present invention. The print circuit board 32
is with a cavity for positioning the heat source 30 that is
connected to one bonding pad (not shown) on the surface of the
print circuit board 32 with conductive wires 35 for electrically
connecting with the heat source 30 and print circuit board 32. The
cavity is full of the molding compound 34 that also covers the heat
source 30 and the conductive structures 33. The print circuit board
32 also includes other conductive structures 33 positioned on the
other surface of the print circuit board 32 for the electrical
connection with an exterior device. With any suitable method, such
as an adhesion layer is attached to the other surface of the print
circuit board 32 for attaching the heat source 30. Such as a
cooling structure of solid state 20 applied to a package structure
of cavity down is beneficial for the design of heat sink for the
whole package structure.
[0032] FIG. 3C is a cross-sectional diagram illustrating a cooling
structure of solid state applied to a lead-frame package in
accordance with the present invention. The heat source 30 is
attached on the structure of passive cooling 22b of the 20a with an
adhesive layer of thermal-conductive insulation. The inner leads 36
of a lead-frame are connected to the bonding pads (not shown) on
the surface of the heat source 30 with the conductive wires 35, so
as to electrically connect with the heat source 30 and the
lead-frame. The molding compound 34 encapsulates the heat source
30, the conductive structures 33, the partial conductive wires 35
and around the structure of passive cooling 22b. Such as a cooling
structure of solid state 20 applied to a package structure of
lead-frame is beneficial for the design of heat sink for the whole
package structure.
[0033] FIG. 3D is a cross-sectional diagram illustrating a cooling
structure of solid state applied to multi-chip package in
accordance with the present invention. The package structures of
lead-frame in FIG. 3 are attached on the print circuit board 32
with soldering. Furthermore, the size of the structure of passive
cooling 22a of the cooling structure of solid state 20 would cover
a plurality of package structures of lead-frame and be extended to
the print circuit board 32. Such as a cooling structure of solid
state 20 applied to a multi-chip package is beneficial for the
design of heat sink for the whole package structure.
[0034] Accordingly, the exemplary cooling structure of solid state
20 would be integrated into the heat sink of a package structure
and applied to single chip, multi-chip or a wafer, as well as a
wafer-level package. It is understandable that the structure of
passive cooling 22a, 22b of the cooling structure of solid state 20
and the structure of active cooling 10 would have variable shapes,
sizes, and numbers for a desired requirement. Thus, the issue of
conventional hot spots would be resolved by the compact structure
of the present invention.
[0035] FIG. 4A to FIG. 4D is a cross-sectional diagram that
illustrating a cooling structure of solid state integrated to a
package structure of wire bond. It is noted that the exemplary
package structure herein would be integrated into any type of
package. Moreover, the exemplary single chip integrated with the
cooling structure of solid state would be in the process of
packaging single chip or un-sawed chips in the wafer-level
structure. Furthermore, the circuit related to control an active
cooling structure is not shown herein without limitation of the
claimed scope.
[0036] Referring to FIG. 4A, a substrate 40 is provided for
subsequently forming the heat fin 23 and backplate 24. In one
embodiment, the substrate 40 is made of the materials with good
thermo-conductivity, such as metal copper, aluminum, or copper,
aluminum or silicon alloy, and has two surface 40a and 40b facing
with each other. Furthermore, the substrate 40 is with the
available shape or size, such as a circle similar to the size of a
wafer or square similar to the size of a chip. Next, an insulation
film 45 and a layer of inter connection (not shown) such as a
metallic layer is subsequently formed on the surface 40a of the
substrate 40. The portion of the layer of inter connection is
removed to form a plurality structure of interconnection 42
position the surface 40a. With any suitable method, such as screen
printing, a solder paste 44 is positioned on each the structure of
interconnection 42 for sequential adhesion. It is noted that such a
conductive junction 12 (or 12a, 12b) consists of the structure of
interconnection 42 and the solder paste 44. In other embodiment, on
the surface 40a, the portion of the substrate 40 is removed with
lithography and etching to form a plurality of heat fins 23. The
heat fins 23 are configured for not only heat dissipation but also
attachment, as well as the structure of passive cooling 22a in FIG.
3D.
[0037] Furthermore, the insulation film 45 is implemented by
sintering. Alternatively, the insulation film 45 is formed by
electroplating. The thermo resistance would be neglect because of
the thin thickness of the insulation film 45.
[0038] Referring to FIG. 4B, on the other surface 40b of the
substrate 40, the portion of the substrate 40 is removed with
lithography and etching, such as micro electromechanical
processing, semiconductor processing or precision machine
processing, to form a plurality of isolated heat fin 23. The
residual substrate 40 at the bottom connecting the heat fins 23 is
the backplate 24. Furthermore, with any suitable method, such as
sputtering, evaporation or electroplating, the components
thermoelectric elements 11a and 11b of the structure of active
cooling 10 are positioned on the 44. Moreover, the arrangement of
the structure of active cooling 10 on the backplate 24 would be
interlacing, facing, or other types. Next, the structure 25 of the
cooling structure of solid state 20 is attached with the solder
paste 44.
[0039] Next, referring to FIG. 4C, a package structure 50 includes
an attached structure of passive cooling 22b. Similar to FIG. 4A,
an insulation layer 51 and a layer of interconnection (not shown),
such as a metallic layer, are sequentially formed on one surface
46a of the structure of passive cooling 22b. The portion of the
layer of inter connection is removed to form a plurality structure
of interconnection 47 position the surface 46a. With any suitable
method, such as printing, a solder paste 49 is positioned on each
the structure of interconnection 47. Furthermore, the structures of
interconnection 47 are substantially on the heat source 30 for the
path reduction of heat flow.
[0040] Referring to FIG. 4D includes the package structure 50 of
FIG. 4C and the structure 25 of FIG. 4B. The structure of active
cooling 10 in the structure 25 is positioned on the solder paste 49
of the package structure 50, such as with flip chip technology. It
is understandable that a plurality of conductive structures 33 are
positioned, with any suitable method such as bumping, on the other
surface of the print circuit board 32, and then reflowed to connect
with the package structure 50 and the structure 25. Accordingly,
during the manufacture of the cooling structure of solid state,
some components are first integrated into a precedent package
structure and then attached to other components. It is not
necessary for such a cooling structure of solid state to attach a
device with a conventional mechanical method or other device, so
the problems on thermo resistance and hot spot would be reduced or
avoided.
[0041] In addition of the formation of package device with the
cooling structure, the exemplary embodiment according to the
present invention is implemented by forming the cooling structure
of solid state followed by the integration with the package
structure. FIG. 5A to FIG. 5D are schematically cross-sectional
diagrams illustrating an exemplary cooling structure of solid state
integrated into a package structure of wire bond in accordance with
the present. Different from the precedent embodiment, referring to
FIG. 5A, the structure of active cooling 10 of this embodiment is
positioned to the structure of passive cooling 22b in the package
structure but not integrated. Similarly, an insulation layer 51,
the structure of interconnection 47 and solder paste 49 constituted
the conductive junction 12, 12a or 12b are formed on the surface
46a of the structure of passive cooling 22b. Next, the components
of the structure of active cooling 10 are positioned on the solder
paste 49 with any suitable methods and then reflowed. Furthermore,
the structure of passive cooling 22b would be combined with a
molding compound 52 first and then used in the assignment of the
structure of active cooling 10, such as FIG. 6.
[0042] Referring to FIG. 5B, the manufacture of the structure of
passive cooling 22a is similar to the precedent embodiment, but
without the assignment of the structure of active cooling 10 on the
44. Next, the components of FIG. 5A and FIG. 5B are assembled with
reflowing and then integrated with the heat source 30 on the print
circuit board 32, shown in FIG. 5C. Next, the cooling structure of
solid state is adhered and attached to the print circuit board 32
with the molding compound 34, shown as FIG. 5D.
[0043] When there has been illustrated and described what is at
present invention considered to be a preferred embodiment of the
present invention, it will be understood by those skilled in the
art that various changes and modifications may be made, and
equivalents may be substituted for elements thereof without
departing from the true scope of the invention. In addition, may
modifications may be made to adapt a particular situation or
material to the teachings of the invention without departing from
the true scope thereof. Therefore, it is intended that this
invention not be limited to template for carrying out the
invention, but that the invention will include all embodiments
falling within the scope of the appended claims.
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