U.S. patent application number 13/540504 was filed with the patent office on 2012-11-01 for heat dissipating circuit board and method of manufacturing the same.
This patent application is currently assigned to SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Seog Moon CHOI, Shan GAO, Tae Hyun KIM, Young Ki LEE, Chang Hyun LIM, Hye Sook SHIN.
Application Number | 20120273558 13/540504 |
Document ID | / |
Family ID | 43755648 |
Filed Date | 2012-11-01 |
United States Patent
Application |
20120273558 |
Kind Code |
A1 |
SHIN; Hye Sook ; et
al. |
November 1, 2012 |
HEAT DISSIPATING CIRCUIT BOARD AND METHOD OF MANUFACTURING THE
SAME
Abstract
Disclosed is a heat dissipating circuit board, which includes a
metal core including an insulating layer formed on the surface
thereof, a circuit layer formed on the insulating layer and
including a seed layer and a first circuit pattern, and a heat
dissipating frame layer bonded onto the circuit layer using solder
and having a second circuit pattern, and in which the heat
dissipating frame layer is bonded onto the circuit layer not by a
plating process but by using solder, thus reducing the cost and
time of the plating process and relieving stress applied to the
heat dissipating circuit board due to the plating process. A method
of manufacturing the heat dissipating circuit board is also
provided.
Inventors: |
SHIN; Hye Sook; (Gyunggi-do,
KR) ; CHOI; Seog Moon; (Seocho-gu, KR) ; GAO;
Shan; (Gyunggi-do, KR) ; LIM; Chang Hyun;
(Seoul, KR) ; KIM; Tae Hyun; (Seoul, KR) ;
LEE; Young Ki; (Gyunggi-do, KR) |
Assignee: |
SAMSUNG ELECTRO-MECHANICS CO.,
LTD.
Gyunggi-do
KR
|
Family ID: |
43755648 |
Appl. No.: |
13/540504 |
Filed: |
July 2, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12614405 |
Nov 7, 2009 |
8242371 |
|
|
13540504 |
|
|
|
|
Current U.S.
Class: |
228/211 ;
228/203 |
Current CPC
Class: |
H05K 1/053 20130101;
H05K 3/202 20130101; Y10T 29/49126 20150115; H05K 1/0209 20130101;
H05K 7/205 20130101; Y10T 29/49155 20150115; H05K 2201/066
20130101; Y10T 29/49124 20150115; H05K 3/341 20130101; H05K 1/0263
20130101; H05K 3/24 20130101 |
Class at
Publication: |
228/211 ;
228/203 |
International
Class: |
B23K 1/20 20060101
B23K001/20 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 23, 2009 |
KR |
10-2009-0090162 |
Claims
1. A method of manufacturing a heat dissipating circuit board,
comprising: (A) forming an insulating layer on a surface of a metal
core; (B) forming a circuit layer including a seed layer and a
first circuit pattern on the insulating layer; (C) preparing a heat
dissipating frame layer having a second circuit pattern; and (D)
bonding the heat dissipating frame layer onto the circuit layer
using solder.
2. The method as set forth in claim 7, wherein, in (C), the heat
dissipating frame layer has a thickness equal to or greater than
tens of .mu.m.
3. The method as set forth in claim 7, wherein (A) comprises: (A1)
preparing a metal core comprising aluminum; and (A2) anodizing the
metal core thus forming an insulating layer comprising
Al.sub.2O.sub.3.
4. The method as set forth in claim 7, wherein, in (C), the second
circuit pattern is formed to be same as the first circuit
pattern.
5. The method as set forth in claim 7, wherein, in (C), the second
circuit pattern is formed to be different from the first circuit
pattern.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This divisional application claims the benefit of U.S.
patent application Ser. No. 12/614,405, filed Nov. 7, 2009,
entitled "Heat Dissipating Circuit Board and Method of
Manufacturing the Same" which claims benefit of Korean Patent
Application No. 10-2009-0090162, filed Sep. 23, 2009, entitled "A
Radiant Heat Circuit Board and a Method of Manufacturing the Same",
which is hereby incorporated by reference in its entirety into this
application.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to a heat dissipating circuit
board and a method of manufacturing the same.
[0004] 2. Description of the Related Art
[0005] Alongside the recent advancement of the electronics industry
is a drastically increasing demand for electronic parts with
increased functionality. Circuit boards which mount electronic
parts which are lightweight, slim, short and small should be able
to integrate many electronic products on a small area of the
circuit board.
[0006] Meanwhile, provided on the circuit board is a heating device
such as a semiconductor device or a light emitting diode. However,
this device emits a very large amount of heat. If heat generated by
the heating device does not rapidly dissipate, the temperature of
the circuit board increases, undesirably causing operation of the
heating device to become impossible and the heating device to
operate improperly. Thus, circuit boards having improved heat
dissipation properties are being researched.
[0007] FIG. 1 is a cross-sectional view showing a conventional heat
dissipating circuit board. With reference to FIG. 1, the heat
dissipating circuit board and the method of manufacturing the same
are described below.
[0008] First, a metal core 11 is subjected to for example anodizing
treatment which forms an insulating layer 12 on both surfaces
thereof.
[0009] Next, a plating process and an etching process are performed
on the insulating layer 12, thus forming a circuit layer 13.
[0010] Next, a heating device (not shown) is disposed on the
circuit layer 13, and the circuit layer 13 and the heating device
(not shown) are bonded to each other using wire or solder.
[0011] The conventional heat dissipating circuit board is thus
manufactured through the above procedures.
[0012] In the case of the conventional heat dissipating circuit
board, because the metal is very effective in terms of transferring
heat, heat generated from the heating device (not shown) is
dissipated to the outside through the insulating layer 12 and the
metal core 11. Thus, an electronic device formed on the heat
dissipating circuit board is not subjected to comparatively high
heat, and problems of the performance of the electronic device
getting reduced are solved to some degree.
[0013] However, in the case of the conventional heat dissipating
circuit board, the circuit layer 13 should be formed thick so as to
maximize heat dissipation effects. Because the circuit layer 13 is
formed on the insulating layer 12 by a plating process, the
formation of the thick circuit layer 13 undesirably results in
increased plating process time and cost.
[0014] Furthermore, as the process time is prolonged, stress
applied to the heat dissipating circuit board due to the plating
process is undesirably enhanced.
SUMMARY OF THE INVENTION
[0015] Accordingly, the present invention has been made keeping in
mind the problems encountered in the related art and the present
invention is intended to provide a heat dissipating circuit board
in which a thick heat dissipating frame layer is bonded onto a
circuit layer not by a plating process but by using solder thus
reducing the plating process time and cost, and also to provide a
method of manufacturing the same.
[0016] Also the present invention is intended to provide a heat
dissipating circuit board in which the plating process time is
shortened thus relieving stress applied to the heat dissipating
circuit board, and also to provide a method of manufacturing the
same.
[0017] An aspect of the present invention provides a heat
dissipating circuit board, including a metal core including an
insulating layer formed on a surface thereof, a circuit layer
formed on the insulating layer and including a seed layer and a
first circuit pattern, and a heat dissipating frame layer bonded
onto the circuit layer using solder and having a second circuit
pattern.
[0018] In this aspect, the metal core may include aluminum (Al),
and the insulating layer formed on the surface of the metal core
may include Al.sub.2O.sub.3.
[0019] In this aspect, the metal core may further include a through
hole which is formed in the metal core and which is plated at an
inner surface thereof to be connected to the circuit layer, and the
insulating layer is formed in the through hole as well as on the
surface of the metal core.
[0020] In this aspect, the heat dissipating frame layer may have a
thickness equal to or greater than tens of .mu.m.
[0021] In this aspect, the second circuit pattern may be formed to
be the same as the first circuit pattern.
[0022] Alternatively, the second circuit pattern may be formed to
be different from the first circuit pattern.
[0023] Another aspect of the present invention provides a method of
manufacturing the heat dissipating circuit board, including (A)
forming an insulating layer on a surface of a metal core, (B)
forming a circuit layer including a seed layer and a first circuit
pattern on the insulating layer, (C) preparing a heat dissipating
frame layer having a second circuit pattern, and (D) bonding the
heat dissipating frame layer onto the circuit layer using
solder.
[0024] In this aspect, in (C), the heat dissipating frame layer may
have a thickness equal to or greater than tens of .mu.m.
[0025] In this aspect, (A) may include (A1) preparing a metal core
comprising aluminum and (A2) anodizing the metal core thus forming
an insulating layer comprising Al.sub.2O.sub.3.
[0026] In this aspect, in (C), the second circuit pattern may be
formed to be the same as the first circuit pattern.
[0027] Alternatively, in (C), the second circuit pattern may be
formed to be different from the first circuit pattern.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The features and advantages of the present invention will be
more clearly understood from the following detailed description
taken in conjunction with the accompanying drawings, in which:
[0029] FIG. 1 is a cross-sectional view showing a conventional heat
dissipating circuit board;
[0030] FIG. 2 is a cross-sectional view showing a heat dissipating
circuit board according to a first embodiment of the present
invention;
[0031] FIG. 3 is an exploded perspective view showing the heat
dissipating circuit board of FIG. 2;
[0032] FIG. 4 is an exploded perspective view showing a heat
dissipating circuit board according to a second embodiment of the
present invention;
[0033] FIGS. 5 to 8 are perspective views sequentially showing a
process of manufacturing the heat dissipating circuit board of FIG.
2; and
[0034] FIGS. 9 to 12 are perspective views sequentially showing a
process of manufacturing the heat dissipating circuit board of FIG.
4.
DESCRIPTION OF SPECIFIC EMBODIMENTS
[0035] Hereinafter, embodiments of the present invention will be
described in detail while referring to the accompanying drawings.
Throughout the drawings, the same reference numerals are used to
refer to the same or similar elements. In the description, the
terms "first", "second" and so on are used only to distinguish one
element from another element, and the elements are not defined by
the above terms. Furthermore, descriptions of known techniques,
even if they are pertinent to the present invention, are regarded
as unnecessary and may be omitted in so far as they would make the
characteristics of the invention unclear and muddy the
description.
[0036] Furthermore, the terms and words used in the present
specification and claims should not be interpreted as being limited
to typical meanings or dictionary definitions, but should be
interpreted as having meanings and concepts relevant to the
technical scope of the present invention based on the rule
according to which an inventor can appropriately define the concept
implied by the term to best describe the method he or she knows for
carrying out the invention.
[0037] Heat Dissipating Circuit Board
[0038] FIG. 2 is a cross-sectional view showing a heat dissipating
circuit board 100a according to a first embodiment of the present
invention, and FIG. 3 is an exploded perspective view showing the
heat dissipating circuit board of FIG. 2. With reference to these
drawings, the heat dissipating circuit board 100a according to the
present embodiment is described below.
[0039] As shown in FIGS. 2 and 3, the heat dissipating circuit
board 100a according to the present embodiment is configured such
that a heat dissipating frame layer 105a is formed on an insulating
layer 102 not through direct plating but by using solder 104a, thus
exhibiting high heat dissipation properties.
[0040] Specifically, the insulating layer 102 is formed on a metal
core 101, and a circuit layer 103 including a seed layer is formed
on the insulating layer 102 through plating. Further, the heat
dissipating frame layer 105a is bonded onto the circuit layer 103
using solder 104a. Although FIGS. 2 and 3 illustrate the formation
of the insulating layer 102, the circuit layer 103 and the heat
dissipating frame layer 105a only on one surface of the metal core
101, the present invention is not limited thereto. The insulating
layer 102, the circuit layer 103 and the heat dissipating frame
layer 105a may be formed on both surfaces of the metal core
101.
[0041] The metal core 101 which functions to improve heat
dissipation properties may be made of aluminum. As such, the
insulating layer 102 may be made of Al.sub.2O.sub.3 formed by
anodizing aluminum. Further, a through hole (not shown) may be
formed in the metal core 101, and the inner surface of the through
hole (not shown) is plated so that circuit layers 103 formed on
both surfaces of the metal core 101 may be connected to each
other.
[0042] The circuit layer 103 is formed on the insulating layer 102.
The circuit layer 103 may include a seed layer and a plating layer
formed on the seed layer. According to the present invention,
because the heat dissipating frame layer 105a is separately
provided through a subsequent procedure, the circuit layer 103
which is formed by a plating process may be formed thin compared to
the conventional technique. The circuit layer 103 may have a
thickness ranging from ones to tens of .mu.m. In the case where the
circuit layer 103 is formed to be thicker than tens of .mu.m, high
stress may be undesirably applied to the heat dissipating circuit
board 100a.
[0043] The heat dissipating frame layer 105a is formed in such a
manner that it is bonded onto the circuit layer 103 using the
solder 104a in a state in which a second circuit pattern 107a has
been formed thereon, unlike in the conventional technique which
forms it to be thick through direct plating on an insulating layer.
The heat dissipating frame layer 105a is formed of the same metal
as was used for the circuit layer 103 and has a thickness equal to
or greater than tens of .mu.m in order to improve heat dissipation
properties. In the case where the heat dissipating frame layer 105a
is formed much thicker than the circuit layer 103, heat generated
from a heating device (not shown) mounted on the heat dissipating
frame layer 105a may be rapidly transferred to the outside of the
metal core 101 or the heat dissipating circuit board 100a via the
heat dissipating frame layer 105a.
[0044] The solder 104a functions to bond the heat dissipating frame
layer 105a and the circuit layer 103 to each other so that heat
generated from the heating device (not shown) is transferred to the
metal core 101, and also functions to electrically connect the heat
dissipating frame layer 105a and the circuit layer 103 to each
other so that the heat dissipating frame layer 105a plays a role as
a circuit pattern. The material used for the solder 104a may
include any bonding metal which is typically known in the art, for
example, a metal such as soft solder having a low melting
point.
[0045] In the present embodiment, the first circuit pattern 106 of
the circuit layer 103 and the second circuit pattern 107a of the
heat dissipating frame layer 105a are formed in the same shape.
Thus, the heating device (not shown) may be situated on any pattern
where the first circuit pattern 106 is formed, and heat generated
from the heating device (not shown) may be transferred to the metal
core 101 via the heat dissipating frame layer 105a, the solder
104a, and the circuit layer 103 in this sequential order.
[0046] The solder 104a is disposed under the heat dissipating frame
layer 105a and is not exposed in the final product. Hence, the
pattern of the solder 104a is the same as the second circuit
pattern 107a of the heat dissipating frame layer 105a, and may thus
be the same as the first circuit pattern 106.
[0047] FIG. 4 is an exploded perspective view showing a heat
dissipating circuit board 100b according to a second embodiment of
the present invention. With reference to this drawing, the heat
dissipating circuit board 100b according to the present embodiment
is described below. In the description of the present embodiment,
elements which are the same as or similar to those of the previous
embodiment are designated by the same reference numerals, and
redundant descriptions thereof are omitted.
[0048] As shown in FIG. 4, the heat dissipating circuit board 100b
according to the present embodiment is configured such that an
insulating layer 102 is formed on a metal core 101, a circuit layer
103 including a seed layer is formed on the insulating layer 102 by
a plating process, and a heat dissipating frame layer 105b is
bonded onto the circuit layer 103 using solder 104b, in which the
first circuit pattern 106 of the circuit layer 103 is different
from the second circuit pattern 107b of the heat dissipating frame
layer 105b.
[0049] Specifically, the first circuit pattern 106 is formed to be
different from the second circuit pattern 107b, but the second
circuit pattern 107b may be formed to be the same as part of the
first circuit pattern 106. Thus, the heat dissipating frame layer
105b is bonded only to a position where a heating device (not
shown) is disposed on the circuit layer 103, thus reducing the
processing time and cost.
[0050] The pattern formed on the solder 104b is the same as the
second circuit pattern 107b, and thus may be formed to be the same
as part of the first circuit pattern 106 as in the second circuit
pattern 107b.
[0051] Method of Manufacturing Heat Dissipating Circuit Board
[0052] With reference to FIGS. 5 to 8, the method of manufacturing
the heat dissipating circuit board 100a according to the first
embodiment of the present invention is described below.
[0053] First, as shown in FIG. 5, an insulating layer 102 is formed
on the surface of a metal core 101. Although FIG. 5 illustrates the
formation of the insulating layer 102 only on the upper surface of
the metal core 101, the insulating layer 102 may be formed on the
entire surface of the metal core 101.
[0054] As such, the metal core 101 may be made of aluminum, and the
insulating layer 102 may be made of Al.sub.2O.sub.3 resulting from
anodizing the metal core 101. In the case where the metal core 101
is made of aluminum, heat dissipation properties of the heat
dissipating circuit board 100a may be effectively improved.
[0055] Next, as shown in FIG. 6, a circuit layer 103 including a
seed layer and a first circuit pattern 106 is formed on the
insulating layer 102.
[0056] Specifically, for example, an electroless plating process or
a sputtering process is performed on the insulating layer 102, thus
forming the seed layer. As such, the seed layer facilitates the
bonding between the plating layer and the insulating layer 102, so
that the circuit layer 103 is easily bonded onto the insulating
layer 102.
[0057] After the formation of the seed layer, the circuit layer 103
is formed on the seed layer. The first circuit pattern 106 of the
circuit layer 103 is formed by a plating process and an etching
process. Particularly useful is a typically known process, for
example, a subtractive process, an additive process, a
semi-additive process, or a modified semi-additive process. The
circuit layer 103 may have a thickness ranging from ones to tens of
gm. In the case where the circuit layer 103 is formed thicker than
tens of .mu.m, stress applied to the heat dissipating circuit board
100a may be enhanced through a plating process for a long period of
time.
[0058] Next, as shown in FIG. 7, a heat dissipating frame layer
105a having a second circuit pattern 107a is prepared.
[0059] The heat dissipating frame layer 105a may be separately
manufactured to have a predetermined pattern shape using a typical
process known in the art without particular limitation. Also, in
order to improve heat dissipation properties of the heat
dissipating frame layer 105a, it is desirable that the heat
dissipating frame layer 105a be formed at a thickness equal to or
greater than tens of .mu.m. Because the thick heat dissipating
frame layer 105a is not formed on the insulating layer 102 through
direct plating, stress directly applied to the heat dissipating
circuit board due to the plating process may be avoided.
[0060] The second circuit pattern 107a of the heat dissipating
frame layer 105a may be formed to be the same as the first circuit
pattern 106 of the circuit layer 103.
[0061] Next, as shown in FIG. 8, the heat dissipating frame layer
105a is bonded onto the circuit layer 103 using solder 104a.
[0062] The material of the solder 104a may include any metal, in
particular, soft solder. In the case of soft solder, it has a low
melting point, and thus a bonding process using the solder 104a may
be carried out at low temperature and stress applied to the heat
dissipating circuit board 100a may be relieved.
[0063] The pattern formed on the solder 104a may have the same
shape as the second circuit pattern 107a. In this case, all of the
pattern of the solder 104a, the first circuit pattern 106 and the
second circuit pattern 107a may have the same shape.
[0064] The heat dissipating circuit board 100a according to the
first embodiment, as shown in FIG. 8, may be manufactured by the
above manufacturing process.
[0065] With reference to FIGS. 9 to 12, the method of manufacturing
the heat dissipating circuit board 100b according to the second
embodiment of the present invention is described below. In the
description of the present embodiment, elements which are the same
as or similar to those of the previous embodiment are designated by
the same reference numerals, and redundant descriptions thereof are
omitted.
[0066] First, as shown in FIG. 9, an insulating layer 102 is formed
on a metal core 101. Next, as shown in FIG. 10, a circuit layer 103
including a seed layer and a first circuit pattern 106 is formed on
the insulating layer 102.
[0067] Next, as shown in FIG. 11, a heat dissipating frame layer
105b having a second circuit pattern 107b is prepared. As such, the
second circuit pattern 107b and the first circuit pattern 106 are
formed to be different from each other, and the second circuit
pattern 107b may be formed to be the same as part of the first
circuit pattern 106.
[0068] Next, as shown in FIG. 12, the heat dissipating frame layer
105b is bonded onto the circuit layer 103 using solder 104b. The
pattern of the solder 104b may be the same as the second circuit
pattern 107b. In this case, the pattern of the solder 104b is also
different from the first circuit pattern 106 and may be formed to
be the same as part of the first circuit pattern 106, as in the
second circuit pattern 107b.
[0069] The heat dissipating circuit board 100b according to the
second embodiment, as shown in FIG. 12, may be manufactured by the
above manufacturing process.
[0070] As described hereinbefore, the present invention provides a
heat dissipating circuit board and a method of manufacturing the
same. According to the present invention, the heat dissipating
circuit board is configured such that a circuit layer is formed to
a thickness ranging from ones to tens of .mu.m on an insulating
layer, and a thick heat dissipating frame layer having a thickness
equal to or greater than tens of .mu.m is bonded onto the circuit
layer using solder, thus reducing the plating process time and
cost, thereby reducing the net time and cost required to
manufacture the heat dissipating circuit board.
[0071] Also, according to the present invention, because the
plating process time is reduced, stress applied to the heat
dissipating circuit board during the plating process can be
relieved.
[0072] Also, according to the present invention, a first circuit
pattern of the circuit layer is formed to be the same as a second
circuit pattern of the heat dissipating frame layer, thus improving
heat dissipation effects and enabling a heating device to be
disposed on any pattern where the first circuit pattern is
formed.
[0073] Also, according to the present invention, the first circuit
pattern and the second circuit pattern can be formed to be
different from each other. As such, the second circuit pattern is
formed to be the same as part of the first circuit pattern.
Thereby, the heat dissipating frame layer is bonded only to a
position where a heating device is disposed, thus reducing the cost
required to manufacture the heat dissipating circuit board.
[0074] Also, according to the present invention, because the solder
is made of metal, it can transfer heat emitted from the heat
dissipating frame layer to the circuit layer, and also can
electrically connect the heat dissipating frame layer and the
circuit layer to each other so that the heat dissipating frame
layer plays a role as a circuit pattern.
[0075] Although the embodiments of the present invention regarding
the heat dissipating circuit board and the method of manufacturing
the same have been disclosed for illustrative purposes, those
skilled in the art will appreciate that a variety of different
modifications, additions and substitutions are possible, without
departing from the scope and spirit of the invention as disclosed
in the accompanying claims. Accordingly, such modifications,
additions and substitutions should also be understood as falling
within the scope of the present invention.
* * * * *