U.S. patent application number 14/244834 was filed with the patent office on 2014-08-07 for power module package and method for fabricating the same.
This patent application is currently assigned to SAMSUNG ELECTRO-MECHANICS CO., LTD.. The applicant listed for this patent is SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Seong Moon Choi, Kwang Soo Kim, Young Ki Lee, Ji Hyun Park.
Application Number | 20140220736 14/244834 |
Document ID | / |
Family ID | 47353032 |
Filed Date | 2014-08-07 |
United States Patent
Application |
20140220736 |
Kind Code |
A1 |
Kim; Kwang Soo ; et
al. |
August 7, 2014 |
POWER MODULE PACKAGE AND METHOD FOR FABRICATING THE SAME
Abstract
Disclosed herein are a power module package and a method for
manufacturing the same. The power module package includes: first
and second lead frames arranged to face each other, both or either
of the first and second frames being made of aluminum; anodized
layers formed on portions of the lead frame(s) made of aluminum in
the first and second lead frames; and semiconductor devices mounted
on first surfaces of the first and second lead frames.
Inventors: |
Kim; Kwang Soo; (Suwon-si,
KR) ; Park; Ji Hyun; (Seoul, KR) ; Lee; Young
Ki; (Hwaseong-si, KR) ; Choi; Seong Moon;
(Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRO-MECHANICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Assignee: |
SAMSUNG ELECTRO-MECHANICS CO.,
LTD.
Suwon-si
KR
|
Family ID: |
47353032 |
Appl. No.: |
14/244834 |
Filed: |
April 3, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13235176 |
Sep 16, 2011 |
8729683 |
|
|
14244834 |
|
|
|
|
Current U.S.
Class: |
438/107 |
Current CPC
Class: |
H01L 2224/92247
20130101; H01L 2924/15724 20130101; H01L 2924/13055 20130101; H01L
2224/43 20130101; H01L 2224/48137 20130101; H01L 2224/73265
20130101; H01L 23/49575 20130101; H01L 2224/73265 20130101; H01L
2224/32245 20130101; H01L 2924/15724 20130101; H01L 23/49586
20130101; H01L 2924/181 20130101; H01L 2924/13055 20130101; H01L
2224/92247 20130101; H01L 23/3107 20130101; H01L 2924/00014
20130101; H01L 2924/00014 20130101; H01L 2924/00 20130101; H01L
2224/48247 20130101; H01L 2924/00 20130101; H01L 2224/45099
20130101; H01L 2924/00 20130101; H01L 2224/32245 20130101; H01L
2924/00 20130101; H01L 2224/48247 20130101; H01L 2224/32245
20130101; H01L 2924/00012 20130101; H01L 2924/00012 20130101; H01L
2224/05599 20130101; H01L 2224/32245 20130101; H01L 2224/48247
20130101; H01L 23/49568 20130101; H01L 2224/48247 20130101; H01L
2924/1305 20130101; H01L 2924/181 20130101; H01L 24/48 20130101;
H01L 23/49537 20130101; H01L 2224/73265 20130101; H01L 2924/00014
20130101; H01L 2924/1305 20130101; H01L 2224/73265 20130101; H01L
24/43 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
438/107 |
International
Class: |
H01L 23/00 20060101
H01L023/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 16, 2011 |
KR |
10-2011-0058468 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. A method for fabricating a power module package, comprising:
preparing first and second lead frames which are arranged to face
each other, both of or either of the first and second lead frames
being made of aluminum; forming anodized layers on portions of the
lead frame(s) made of aluminum in the first and second lead frames;
and mounting semiconductor devices on first surfaces of the first
and second lead frames, respectively.
13. The method as set forth in claim 12, wherein in the forming of
the anodized layers, the anodized layers are formed on the regions
where the semiconductor devices are to be mounted, in the first
surfaces of the first and second lead frames, and on second
surfaces of the first and second lead frames.
14. The method as set forth in claim 12, wherein in the forming of
the anodized layers, the anodized layers are formed on the second
surfaces of the first and second lead frames.
15. The method as set forth in claim 12, wherein in the mounting of
the semiconductor devices, the semiconductor devices include a
power device and a control device respectively mounted on the first
surfaces of the first lead frame and the second lead frame.
16. The method as set forth in claim 12, wherein the first lead
frame is made of aluminum, and in the mounting of the semiconductor
devices, the power device is mounted on the first surface of the
first lead frame.
17. The method as set forth in claim 12, further comprising forming
metal layers for circuit on the regions where the semiconductor
devices are to be mounted, in the anodized layers, after the
forming of the anodized layers and before the mounting of the
semiconductor devices.
18. The method as set forth in claim 12, further comprising forming
wires for electric connection between the semiconductor devices and
the first and second lead frames, or between the semiconductor
devices, after the mounting of the semiconductor devices.
19. The method as set forth in claim 18, further comprising forming
a molding covering a region between the first and second lead
frames, and the semiconductor devices mounted on the first and
second lead frames, after the forming of the wires.
20. The method as set forth in claim 12, further comprising forming
metal layers for soldering on soldering regions of the lead
frame(s) made of aluminum in the first and second lead frames.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Patent
Application No. 10-2011-0058468, filed on Jun. 16, 2011, entitled
"Power Module Package and Method for
[0002] Manufacturing the Same", which is hereby incorporated by
reference in its entirety into this application.
BACKGROUND OF THE INVENTION
[0003] 1. Technical Field
[0004] The present invention relates to a power module package and
a method for fabricating the same.
[0005] 2. Description of the Related Art
[0006] As energy usage increases over the world, a large interest
has begun to focus on effective use of restricted energy.
Accordingly, utilization of an inverter to which an intelligent
power module (IPM) for efficient conversion used in the existing
home or industrial products is applied is accelerating.
[0007] As the application of this power module is expanding, high
integration, high capacity and miniaturization are increasingly
required by the market. For this reason, the solution to heat
generation problem of electronic parts becomes an important
issue.
[0008] Therefore, there is required a high heat-radiation package
structure for solving the problem with respect to generation of
heat, in order to increase efficiency and secure high reliability
in the power module.
SUMMARY OF THE INVENTION
[0009] The present invention has been made in an effort to provide
a power module package capable of effectively removing the heat
generated from semiconductor devices and a method for fabricating
the same.
[0010] Further, the present invention has been made in an effort to
provide a power module package capable of being easily fabricated
and reducing the module fabrication costs.
[0011] According to a preferred embodiment of the present
invention, there is provided a power module package, including:
first and second lead frames arranged to face each other, both or
either of the first and second frames being made of aluminum;
anodized layers formed on portions of the lead frame(s) made of
aluminum in the first and second lead frames; and semiconductor
devices mounted on first surfaces of the first and second lead
frames.
[0012] The anodized layers may be formed on the regions where the
semiconductor devices are to be mounted, in the first surfaces of
the first and second lead frames, and on second surfaces of the
first and second lead frames.
[0013] The anodized layers may be formed on the second surfaces of
the first and second lead frames.
[0014] The semiconductor devices may include a power device and a
control device mounted on the first surfaces of the first lead
frame and the second lead frame, respectively.
[0015] The first lead frame may be made of aluminum, and the power
device may be mounted on the first surface of the first lead
frame.
[0016] The power module package may further include metal layers
for circuit on the regions where the semiconductor devices are to
be mounted, in the first surfaces of the first and second lead
frames. Here, the metal layers for circuit may be formed between
the anodized layers and the semiconductor devices.
[0017] The power module package may further include wires for
electric connection between the semiconductor devices and the first
and second lead frames, or between the semiconductor devices.
[0018] The power module package may further include a molding
covering a region between the first and second lead frames, and the
semiconductor devices mounted on the first and second lead
frames.
[0019] The molding may be formed to expose the second surfaces of
the first and second lead frames.
[0020] The molding may be formed on the second surfaces of the
first and second lead frames.
[0021] The power module package may further include metal layers
for soldering formed on soldering regions of the lead frame(s) made
of aluminum in the first and second lead frames.
[0022] According to another preferred embodiment of the present
invention, there is provided a method for fabricating a power
module package, including: preparing first and second lead frames
which are arranged to face each other, both of or either of the
first and second lead frames being made of aluminum; forming
anodized layers on portions of the lead frame(s) made of aluminum
in the first and second lead frames; and mounting semiconductor
devices on first surfaces of the first and second lead frames,
respectively.
[0023] In the forming of the anodized layers, the anodized layers
may be formed on the regions where the semiconductor devices are to
be mounted, in the first surfaces of the first and second lead
frames, and on second surfaces of the first and second lead
frames.
[0024] In the forming of the anodized layers, the anodized layers
may be formed on the second surfaces of the first and second lead
frames.
[0025] In the mounting of the semiconductor devices, the
semiconductor devices may include a power device and a control
device respectively mounted on the first surfaces of the first lead
frame and the second lead frame.
[0026] The first lead frame may be made of aluminum, and in the
mounting of the semiconductor devices, the power device may be
mounted on the first surface of the first lead frame.
[0027] The method may further include forming metal layers for
circuit on the regions where the semiconductor devices are to be
mounted, in the anodized layers, after the forming of the anodized
layers and before the mounting of the semiconductor devices.
[0028] The method may further include forming wires for electric
connection between the semiconductor devices and the first and
second lead frames, or between the semiconductor devices, after the
mounting of the semiconductor devices.
[0029] The method may further include forming a molding covering a
region between the first and second lead frames and the
semiconductor devices mounted on the first and second lead frames,
after the forming of the wires.
[0030] The method may further includes forming metal layers for
soldering on soldering regions of the lead frame(s) made of
aluminum in the first and second lead frames.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 shows a configuration of a power module package
according to a first preferred embodiment of the present
invention;
[0032] FIG. 2 shows a configuration of a power module package
according to a second preferred embodiment of the present
invention;
[0033] FIG. 3 shows a configuration of a power module package
according to a third preferred embodiment of the present
invention;
[0034] FIG. 4 shows a configuration of a power module package
according to a fourth preferred embodiment of the present
invention; and
[0035] FIGS. 5 to 12 are process flowcharts of a method for
fabricating a power module package according to a preferred
embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] Various objects, advantages and features of the invention
will become apparent from the following description of preferred
embodiments with reference to the accompanying drawings.
[0037] 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 of the term to describe most
appropriately the best method he or she knows for carrying out the
invention.
[0038] The above and other objects, 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 the specification, in adding reference
numerals to components throughout the drawings, it is to be noted
that like reference numerals designate like components even though
components are shown in different drawings. Further, when it is
determined that the detailed description of the known art related
to the present invention may obscure the gist of the present
invention, the detailed description thereof will be omitted. Terms
used in the specification, `first`, `second`, etc., can be used to
describe various components, but the components are not to be
construed as being limited to the terms.
[0039] Hereinafter, preferred embodiments of the present invention
will be described in detail with reference to the accompanying
drawings.
[0040] Power Module Package
[0041] FIG. 1 shows a configuration of a power module package
according to a first preferred embodiment of the present
invention.
[0042] As shown in FIG. 1, a power module package 100 includes
first and second lead frames 111 and 121 which are arranged to face
each other and made of aluminum, anodized layers 112 and 122
respectively formed on portions of the first and second lead frames
111 and 121, and semiconductor devices 114 and 124 respectively
mounted on first surfaces of the first and second lead frames 111
and 121.
[0043] In the preferred embodiments of the present invention, it
will be defined that the first surfaces of the first and second
lead frames mean surfaces on which semiconductor devices are to be
mounted, and second surfaces of the first and second lead frames
mean surfaces opposite to the surfaces on which the semiconductor
devices are to be mounted.
[0044] Here, the first and second lead frames 111 and 121 are
arranged such that they are spaced from and symmetrically to each
other, as shown in FIG. 1.
[0045] The semiconductor devices 114 and 124 include a power device
and a control device. In the first preferred embodiment, the power
device and the control device are mounted on the first surfaces of
the first lead frame 111 and the second lead frame 121,
respectively.
[0046] As such, in the present embodiment of the present invention,
the power device 114 having a high calorific value, such as an
insulated gate bipolar transistor (IGBT), a diode, or the like, and
the control device 124 having a small calorific value, such as a
control integrated circuit (IC), are separately mounted on the
first lead frame 111 and the second lead frame 121, respectively.
Therefore, it is expected that the heat generated from the power
device does not have an influence on the control device.
[0047] In addition, the power module package 100 further includes
metal layers 113 and 123 for circuit, which are formed on the
regions where the semiconductor devices 114 and 124 are to be
mounted, in the first surfaces of the first and second lead frames
111 and 121. Here, as shown in FIG. 1, the metal layers 113 and 123
for circuit are formed between the anodized layers 112 and 122 and
the semiconductor devices 114 and 124.
[0048] In addition, the power module package 100 may further
include wires 115 formed for electric connection between the
semiconductor devices 114 and 124 and the first and second lead
frames 111 and 121, or between the semiconductor devices 114 and
124.
[0049] In addition, the power module package 100 may further
include a molding 130 formed for covering a region between the
first and second lead frames 111 and 121, and the semiconductor
devices 114 and 124 mounted on the first and second frames 111 and
121.
[0050] As shown in FIG. 1, the molding 130 is formed such that the
second surfaces of the first and second lead frames 111 and 121 are
exposed.
[0051] According to the present preferred embodiment, the molding
130, which has a relatively lower thermal conductivity than the
anodized layers 112 and 122 and the first and second lead frames
111 and 121 made of aluminum, is not formed on the second surfaces,
which are lower surfaces of the first and second lead frames 111
and 121, thereby effectively transferring the heat generated from
the semiconductor devices 114 and 124 (for example, radiating the
heat through the second surfaces to the outside), resulting in
improvement in heat radiation property.
[0052] In the first preferred embodiment of the present invention,
the anodized layers are formed on the regions where the devices are
to be mounted, in the first surfaces of the first and second lead
frames 111 and 121, and on the second surfaces of the first and
second lead frames 111 and 121.
[0053] Here, the second surfaces on which the anodized layers are
formed, as shown in FIG. 1, mean bottom surfaces of the first and
second lead frames 111 and 121 after forms of the first and second
lead frames are formed. The anodized layers may be formed on other
regions of the second surfaces without limitation thereto,
depending on the needs of operators.
[0054] Here, the anodized layers may be Al.sub.2O.sub.3 layers.
[0055] In addition, the power module package 100 may further
include metal layers 140 for soldering, which are formed on
soldering regions of the lead frame(s) made of aluminum in the
first and second lead frames 111 and 121.
[0056] Here, the metal layers 140 for soldering are configured to
supplement a hardly solderable aluminum material, which may be
realized by performing plating with a solderable metal material
including tin (Sn).
[0057] As shown in FIG.1, the metal layers 140 for soldering may be
formed on both ends of the first and second lead frames 111 and
121, which are regions required to be soldered, after forms of the
first and second lead frames 111 and 121 are formed.
[0058] As shown in FIG. 1, according to the present preferred
embodiment, the anodized layers 112 and 122 are formed on only
desired regions of the first and second lead frames 111 and 121
made of aluminum materials having excellent thermal conductivity,
through selective anode oxidation, and the semiconductor devices
114 and 124 are mounted directly thereon. Therefore, due to the
anodized layers, high insulating properties including high thermal
conductivity can be expected.
[0059] Further, the lead frame itself, which are made of aluminum
materials, functions as a heat radiation substrate, thereby
efficiently transferring the heat from the semiconductor devices
114 and 124, resulting in improvement in heat radiation
property.
[0060] Furthermore, according to the present preferred embodiment,
since a separate substrate for mounting the semiconductor devices
114 and 124 thereon are omitted, the size of the power module
package can be reduced and the fabrication costs can be also
reduced.
[0061] Moreover, in the present preferred embodiment of the present
invention, a down-set structure is not applied to the lead frame,
thereby facilitating a packaging process. Here, the down-set
structure means a structure in which the region of the lead frame,
except a region where the semiconductor device is to be mounted, is
bent to form a step height.
[0062] FIG. 2 shows a configuration of a power module package
according to a second preferred embodiment of the present
invention.
[0063] However, in the second present preferred embodiment, a
description for the same components as those of the first preferred
embodiments will be omitted and a description only for components
different therefrom will be provided.
[0064] As shown in FIG. 2, a power module package 100 includes
first and second lead frames 111 and 121 which are arranged to face
each other and made of aluminum, anodized layers 112 and 122
respectively formed on portions of the first and second lead frames
111 and 121, and semiconductor devices 114 and 124 respectively
mounted on first surfaces of the first and second lead frames 111
and 121.
[0065] In the preferred embodiment of the present invention, it
will be defined that the first surfaces of the first and second
lead frames mean surfaces on which semiconductor devices are to be
mounted, and second surfaces of the first and second lead frames
mean surfaces opposite to the surfaces on which the semiconductor
devices are to be mounted.
[0066] In addition, the power module package 100 further includes
the semiconductor devices 114 and 124, a molding 130, and metal
layers 140 for soldering, and since these are the same as set forth
in the first preferred embodiment, the detailed description related
to these will be omitted.
[0067] Although not shown in FIG. 2, in the second preferred
embodiment, wires are not formed between the semiconductor devices
114 and 124 and the first and second lead frames to 111 and 121,
but formed on other lead frames (not shown) disposed
correspondingly to the first and second lead frames, except the
first and second lead frames.
[0068] The reason of such constitution is to previously prevent a
short, which may occur at the time of electric connection in a case
where the same wires as the first preferred embodiment are embodied
in a structure where an insulating layer is not formed on the first
surfaces of the first and second lead frames 111 and 121.
[0069] Here, the wires formed between the semiconductor devices 114
and 124 may be formed in the same manner as the first preferred
embodiment. The reason is that a collector and an emitter may be
opened or closed by a gate in each of the semiconductor devices 114
and 124.
[0070] The above-described anodized layers 112 and 122 may be
formed on the second surfaces of the first and second lead frames
111 and 121.
[0071] Here, the second surfaces on which the anodized layers are
formed, as shown in FIG. 2, mean bottom surfaces of the first and
second lead frames 111 and 121 after forms of the first and second
lead frames are formed. The anodized layers may be formed on other
regions of the second surfaces without limitation thereto,
depending on the needs of operators.
[0072] In the present preferred embodiment, since the semiconductor
devices 114 and 124 are mounted directly on the first and second
lead frames 111 and 121 and then wire bonding is performed, instead
of embodying separate circuit layers on the first and second lead
frames 111 and 121, heat radiation property can be improved and the
module fabrication costs can be reduced.
[0073] FIG. 3 shows a configuration of a power module package
according to a third preferred embodiment of the present
invention.
[0074] However, in the third present preferred embodiment, a
description for the same components as those of the first preferred
embodiments will be omitted and a description only for components
different therefrom will be provided.
[0075] As shown in FIG. 3, a power module package 100 includes
first and second lead frames 111 and 121 which are arranged to face
each other and made of aluminum, anodized layers 112 and 122
respectively formed on portions of the first and second lead frames
111 and 121, and semiconductor devices 114 and 124 respectively
mounted on first surfaces of the first and second lead frames 111
and 121.
[0076] In the preferred embodiment of the present invention, it
will be defined that the first surfaces of the first and second
lead frames mean surfaces on which semiconductor devices are to be
mounted, and second surfaces of the first and second lead frames
mean surfaces opposite to the surfaces on which the semiconductor
devices are to be mounted.
[0077] In addition, the power module package 100 further includes
the semiconductor devices 114 and 124, and metal layers 140 for
soldering, and since these are the same as set forth in the first
preferred embodiment, the detailed description related to these
will be omitted.
[0078] Although not shown in FIG. 3, in the third preferred
embodiment, wires are not formed between the semiconductor devices
114 and 124 and the first and second lead frames 111 and 121, but
formed on other lead frames (not shown) disposed correspondingly to
the first and second lead frames, except the first and second lead
frames.
[0079] The reason of such constitution is to prevent a short
beforehand, which may occur at the time of electric connection in a
case where the same wires as the first preferred embodiment are
embodied in a structure where an insulating layer is not formed on
the first surfaces of the first and second lead frames 111 and
121.
[0080] Here, the wires formed between the semiconductor devices 114
and 124 may be formed in the same manner as the first preferred
embodiment. The reason is that a collector and an emitter may be
opened or closed by a gate in each of the semiconductor devices 114
and 124.
[0081] In addition, the power module package 100 of the third
preferred embodiment may further include a molding 130 formed for
covering a region between the first and second lead frames 111 and
121, and the semiconductor devices 114 and 124 mounted on the first
and second lead frames 111 and 121.
[0082] In addition, the molding 130 is formed on the second
surfaces of the first and second lead frames 111 and 121.
[0083] The reason is to secure an insulation property without loss
of heat radiation property, by partially covering the second
surfaces corresponding to the bottom surfaces of the first and
second lead frames 111 and 121 with the molding, as shown in FIG.
3, in a case where semiconductor devices requiring high insulation
property is applied to the power module package 100.
[0084] Here, the molding 130 formed above the second surfaces of
the first and second lead frames 111 and 121 needs to be formed
such that it can improve the insulation property without loss of
heat radiation property within the range in which a thickness of
the power module package is less influenced.
[0085] FIG. 4 shows a configuration of a power module package
according to a fourth preferred embodiment of the present
invention.
[0086] As shown in FIG. 4, a power module package 100 includes
first and second lead frame 111 and 121 which are arranged to face
each other, both or either of them being made of aluminum, anodized
layers 112 and 122 respectively formed on portions of the lead
frame(s) in the first and second lead frames 111 and 121, and
semiconductor devices 114 and 124 respectively mounted on first
surfaces of the first and second lead frames 111 and 121.
[0087] In the preferred embodiment of the present invention, it
will be defined that the first surfaces of the first and second
lead frames mean surfaces on which semiconductor devices are to be
mounted, and second surfaces of the first and second lead frames
mean surfaces opposite to the surfaces on which the semiconductor
devices are to be mounted.
[0088] In the present preferred embodiment, the first lead frame
111 may be made of aluminum, and a power device 114 may be mounted
on a first surface of the first lead frame 111.
[0089] Meanwhile, the second lead frame 150 may be formed of any
material that can be generally used as a lead frame material,
besides aluminum.
[0090] As such, only the first lead frame 111, on which the power
device 114 having a high calorific value is mounted, is formed of
aluminum materials, thereby imparting selective heat radiation
property to the power module package and reducing the fabrication
costs of the power module package.
[0091] In addition, the power module package 100 further includes
the semiconductor devices 114 and 124, a molding 130, and metal
layers 140 for soldering, and since these are the same as set forth
in the first preferred embodiment, the detailed description related
to these will be omitted.
[0092] Although not shown in FIG. 4, in the fourth preferred
embodiment, wires are not formed between the semiconductor devices
114 and 124 and the first and second lead frames 111 and 121, but
formed on other lead frames (not shown) disposed correspondingly to
the first and second lead frames, except the first and second lead
frames.
[0093] The reason of such constitution is to prevent a short
beforehand, which may occur at the time of electric connection in a
case where the same wires as the first preferred embodiment are
embodied in a structure where an insulating layer is not formed on
the first surfaces of the first and second lead frames 111 and
121.
[0094] Here, the wires formed between the semiconductor devices 114
and 124 may be formed in the same manner as the first preferred
embodiment. The reason is that a collector and an emitter may be
opened or closed by a gate in each of the semiconductor devices 114
and 124.
[0095] Method for Fabricating Power Module Package
[0096] FIGS. 5 to 12 are process flowcharts of a method for
fabricating a power module package according to a preferred
embodiment of the present invention, which will be described with
reference to FIGS. 1 to 4.
[0097] In the preferred embodiment of the present invention, it
will be defined that the first surfaces of the first and second
lead frames mean surfaces on which semiconductor devices are to be
mounted, and second surfaces of the first and second lead frames
mean surfaces opposite to the surfaces on which the semiconductor
devices are to be mounted.
[0098] First, as shown in FIG. 5, first and second lead frames 111
and 121 are prepared to face each other. Both or either of the
first and second lead frames 111 and 121 is made of aluminum.
[0099] Here, each of the first and second lead frames 111 and 121
may be formed by processing an aluminum plate to have a thickness
and a size set by operators. Here, the thickness of the first and
second lead frames 111 and 121 may be variously selected from 0.1T
to 2.5T depending on the purpose desired by the operators, or,
without limitation thereto, the first and second lead frames 111
and 121 may be processed out of the range from 0.1T to 2.5T.
[0100] Next, as shown in FIG. 6, anodized layers 112 and 122 are
formed on portions of the lead frame(s) made of aluminum in the
first and second lead frames 111 and 121.
[0101] In the present preferred embodiment, Al.sub.2O.sub.3 layers
may be formed on regions of the lead frames, where circuit layers
are to be formed, and on the second surfaces of the lead frames,
within a range of 20 .mu.m to 200 .mu.m, by using a selective
anodizing method, depending on the needs of operators, or without
limitation thereto, Al.sub.2O.sub.3 layers may be processed out of
the above range.
[0102] In addition, the anodized layers 112 and 122 may be formed
by performing a selective anodizing process on regions, where the
anodized layers are required, by using photoresist (PR), dry film
resist (DFR), a metal mask, and a masking resin. Here, the
anodizing process may be performed on the first surfaces and the
second surfaces at the same time, or either the first surfaces or
the second surfaces selectively, in the first and second lead
frames 111 and 121.
[0103] As shown in FIGS. 1 and 6, the anodized layers 112 and 122
according to the first preferred embodiment may be formed on the
regions where the semiconductor devices 114 and 124 are to be
mounted, in the first surfaces of the first and second lead frames
111 and 121, and on the second surfaces of the first and second
lead frames 111 and 121.
[0104] In addition, as shown in FIGS. 2 and 3, the anodized layers
in the second and third preferred embodiments may be formed on the
second surfaces of the first and second lead frames 111 and
121.
[0105] Next, as shown in FIG. 7, the metal layers 113 and 123 for
circuit are formed on the regions where the semiconductor devices
114 and 124 are to be mounted, in the anodized layers.
[0106] Here, the metal layers 113 and 123 for circuit are formed by
forming a metal layer through dry sputtering, or wet electroless
and electrolytic plating, and then forming pads and circuit layers
through wet chemical etching and electrolytic etching, or a
lift-off process.
[0107] In the present preferred embodiment, all the pads and
circuit layers will refer to metal layers 113 and 123 for
circuit.
[0108] For example, the metal layers 113 and 123 for circuit may be
made of any one of Cu, Cu/Ni, Cu/Ti, Au/Pt/Ni/Cu and
Au/Pt/Ni/Cu/Ti, but may be made of other materials applicable to
pads or circuit layers, without limitation thereto. Here, the
symbol "/" will be defined to mean "and".
[0109] Here, the description of the step of forming the metal
layers 113 and 123 for circuit will be omitted due to being the
same description in the second to fourth preferred embodiments
(FIGS. 2 to 4).
[0110] Next, as shown in FIG. 8, the semiconductor devices 114 and
124 are mounted on the first surfaces of the first and second lead
frames 111 and 121.
[0111] Here, a binding material of the semiconductor devices 114
and 124 may be solder or organic resin, but, without limitation
thereto, any binding material that can efficiently transfer the
heat from the semiconductor devices may be applicable.
[0112] Meanwhile, in the first to third preferred embodiments, when
the semiconductor devices are mounted, a power device 114 and a
control device 124 are mounted on the first surfaces of the first
lead frame 111 and the second lead frame 121, respectively.
[0113] As such, in the present embodiment of the present invention,
the power device 114 having a high calorific value, such as, an
insulated gate bipolar transistor (IGBT), a diode, or the like, and
the control device 124 having a small calorific value, such as, a
control integrated circuit (IC), are separately mounted on the
first lead frame 111 and the second lead frame 121, respectively.
Therefore, it is expected that the heat generated from the power
device does not influence the control device.
[0114] In addition, in the fourth preferred embodiment as shown in
FIG. 4, the first lead frame 111 may be made of aluminum, and the
power device 114 may be mounted on the first surface of the first
lead frame 111.
[0115] Meanwhile, the second lead frame 121 may be formed of any
material that can be generally used as a lead frame material,
besides aluminum.
[0116] As such, only the first lead frame 111, on which the power
device 114 having a high calorific value is mounted, is formed of
aluminum materials, thereby imparting selective heat radiation
property to the power module package and reducing fabrication costs
of the power module package.
[0117] Next, as shown in FIG. 9, wires 115 may be formed for
electric connection between the semiconductor devices 114 and 124
and the first and second lead frames 111 and 121, or between the
semiconductor devices 114 and 124.
[0118] Next, as shown in FIG. 10, a molding is formed to cover a
region between the first and second lead frames 111 and 121, and
the semiconductor devices 114 and 124 mounted on the first and
second lead frames 111 and 121.
[0119] In other words, the molding is formed in such a manner that
it surrounds the entire region except regions for connecting with
the outside, in the first and second lead frames 111 and 121, and
the second surfaces of the first and second lead frames 111 and
121.
[0120] If high insulation property is required, as shown in FIG. 3,
the molding may be formed on the second surfaces of the first and
second lead frames 111 and 121.
[0121] Next, as shown in FIG. 11, metal layers 140 for soldering
are formed in soldering regions of the lead frame(s) made of
aluminum in the first and second lead frames 111 and 121.
[0122] Here, the metal layers 140 for soldering are configured to
supplement a hardly solderable aluminum material, which may be
realized by using a solderable metal material including tin
(Sn).
[0123] As shown in FIG. 11, the metal layers 140 for soldering may
be formed on both ends of the first and second lead frames 111 and
121, which are regions required to be soldered.
[0124] Next, as shown in FIG.12, forms of the first and second lead
frames 111 and 121 are formed so that the first and second lead
frames 111 and 121 are coupled with a printed circuit board (not
shown).
[0125] For example, as shown in FIG.12, the forms of the first and
second lead frames 111 and 121 are formed in such a manner that
both sides of the first and second lead frames 111 and 121 are bent
in a vertical direction.
[0126] According to the present invention, the lead frames and the
anode-oxidized metal substrates having excellent heat radiation
property are formed as a single body, thereby shortening heat
radiation path, and thus, the heat generated from the semiconductor
devices can be efficiently radiated.
[0127] Furthermore, according to the present invention, the power
device having a high calorific value and a control device having a
smaller calorific value than the power device and vulnerable to
heat are separately arranged, thereby previously preventing the
heat generated from the power device from influencing the control
device and as a result, improving the reliability and the life time
driving characteristic of products.
[0128] Furthermore, according to the present invention, since the
lead frames and the heat radiation substrate are integrated as a
single body, the fabrication costs of the power module package can
be reduced.
[0129] Moreover, according to the present invention, the down-set
structure is not applied to the lead frame, thereby facilitating a
packaging process and reducing the process costs.
[0130] Although the preferred embodiments of the present invention
have been disclosed for illustrative purposes, they are for
specifically explaining the present invention and thus a power
module package providing a method of manufacturing the same
according to the present invention are not limited thereto, but
those skilled in the art will appreciate that various
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,
variations or equivalent arrangements should be considered to be
within the scope of the invention, and the detailed scope of the
invention will be disclosed by the accompanying claims.
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