U.S. patent application number 14/252780 was filed with the patent office on 2014-08-07 for power module package and method for manufacturing 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 Joon Seok Chae, Young Ki Lee, Bum Seok Suh, Do Jae Yoo.
Application Number | 20140220743 14/252780 |
Document ID | / |
Family ID | 49777251 |
Filed Date | 2014-08-07 |
United States Patent
Application |
20140220743 |
Kind Code |
A1 |
Yoo; Do Jae ; et
al. |
August 7, 2014 |
POWER MODULE PACKAGE AND METHOD FOR MANUFACTURING THE SAME
Abstract
Disclosed herein is a power module package including an external
connection terminal, a substrate in which a fastening unit allowing
one end of the external connection terminal to be insertedly
fastened thereinto is formed to penetrate in a thickness direction
thereof, and a semiconductor chip mounted on one surface of the
substrate.
Inventors: |
Yoo; Do Jae; (Suwon-Si,
KR) ; Lee; Young Ki; (Suwon-Si, KR) ; Suh; Bum
Seok; (Suwon-Si, KR) ; Chae; Joon Seok;
(Suwon-Si, 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: |
49777251 |
Appl. No.: |
14/252780 |
Filed: |
April 15, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13846591 |
Mar 18, 2013 |
|
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14252780 |
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Current U.S.
Class: |
438/123 |
Current CPC
Class: |
H01L 23/142 20130101;
H01L 2224/291 20130101; H01L 2924/13034 20130101; H01L 2924/1305
20130101; H01L 2924/181 20130101; H01L 2924/16151 20130101; H01L
24/45 20130101; H01L 2224/48091 20130101; H01L 2224/45144 20130101;
H01L 2924/13034 20130101; H01L 24/32 20130101; H01L 2224/73265
20130101; H01L 2224/92247 20130101; H01L 2924/13091 20130101; H01L
2924/15787 20130101; H01L 23/492 20130101; H01L 23/055 20130101;
H01L 2224/45124 20130101; H01L 23/495 20130101; H01L 23/49811
20130101; H01L 2924/13055 20130101; H01L 24/96 20130101; H01L
2224/291 20130101; H01L 2224/32225 20130101; H01L 2924/00 20130101;
H01L 2924/00 20130101; H01L 2924/00014 20130101; H01L 2924/00012
20130101; H01L 2924/00014 20130101; H01L 2924/00014 20130101; H01L
2224/48227 20130101; H01L 2224/73265 20130101; H01L 2924/00
20130101; H01L 2924/00014 20130101; H01L 2924/00 20130101; H01L
2224/48227 20130101; H01L 2224/32225 20130101; H01L 2924/00014
20130101; H01L 2924/00 20130101; H01L 2924/00 20130101; H01L
2924/00 20130101; H01L 2924/014 20130101; H01L 2224/48137 20130101;
H01L 2924/15787 20130101; H01L 24/92 20130101; H01L 2924/13055
20130101; H01L 24/29 20130101; H01L 24/48 20130101; H01L 2924/12042
20130101; H01L 25/072 20130101; H01L 23/3735 20130101; H01L 24/73
20130101; H01L 2224/73265 20130101; H01L 2924/12042 20130101; H01L
21/50 20130101; H01L 2924/13091 20130101; H01L 2224/45124 20130101;
H01L 2224/45147 20130101; H01L 2224/45144 20130101; H01L 2924/1305
20130101; H01L 2224/45147 20130101; H01L 2224/48091 20130101; H01L
2224/2919 20130101; H01L 2224/48227 20130101; H01L 2224/92247
20130101; H01L 2924/181 20130101; H01L 23/13 20130101 |
Class at
Publication: |
438/123 |
International
Class: |
H01L 23/495 20060101
H01L023/495; H01L 23/00 20060101 H01L023/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 29, 2012 |
KR |
10-2012-0070666 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. A method for manufacturing a power module package, the method
comprising: preparing a substrate having one surface and the other
surface and including a circuit pattern formed on one surface
thereof and including a chip mounting pad and an external
connection pad; forming an opening penetrating the substrate in a
thickness direction at a portion in contact with the external
connection pad in the substrate; forming a fastening unit in
contact with the external connection pad in the opening; mounting a
semiconductor chip on the chip mounting pad; and insertedly
fastening one end of the external connection terminal into the
fastening unit.
10. The method as set forth in claim 9, wherein in the forming of
the opening penetrating the substrate in the thickness direction,
the opening is formed by using a laser drill or a mechanical
drill.
11. The method as set forth in claim 9, wherein the forming of the
fastening unit includes: inserting a cylindrical member having a
recess formed in a length direction therein into the opening of the
substrate; and pressurizing a portion, of the cylindrical member
inserted into the opening, protruded from the surface of the
substrate.
12. The method as set forth in claim 11, wherein the substrate
includes: a metal plate; an insulating layer formed on one surface
of the metal plate; and a circuit pattern formed on the insulating
layer and including a chip mounting pad and an external connection
pad, wherein the cylindrical member inserted into the opening
includes a portion made of a conductive material and a portion made
of a non-conductive material, wherein the portion made of a
conductive material is in contact with the external connection pad
and the portion made of the non-conductive material is in contact
with the metal plate.
13. The method as set forth in claim 11, wherein the substrate
includes: a metal plate; an insulating layer formed on one surface
of the metal plate; and a circuit pattern formed on the insulating
layer and including a chip mounting pad and an external connection
pad, wherein the cylindrical member inserted into the opening is
made of a non-conductive material; and the method further
comprising: forming a lead frame for electrically connecting the
external connection terminal to the external connection pad, before
the insertedly fastening of the external connection terminal into
the fastening unit.
14. The method as set forth in claim 9, wherein the forming of the
fastening unit includes: mounting a female screw in the opening;
and fastening a male screw having a recess for insertedly fastening
the external connection terminal thereon to the female screw in a
length direction therein.
15. The method as set forth in claim 14, wherein the female screw
is made of a non-conductive material, and the male screw is made of
a conductive material.
16. The method as set forth in claim 9, further comprising: forming
a case on the substrate such that it covers one surface of the
substrate and the semiconductor chip and exposes the other end of
the external connection terminal to the outside, after the
insertedly fastening of the external connection terminal into the
fastening unit.
17. The method as set forth in claim 16, further comprising:
injecting a molding material into the case to form a molding member
covering one surface of the substrate and the semiconductor chip,
after the forming of the case.
18. The method as set forth in claim 9, further comprising:
performing a wire bonding process in order to electrically connect
the semiconductor chip to the circuit pattern, after the mounting
of the semiconductor chip.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Patent
Application No. 10-2012-0070666, filed on Jun. 29, 2012, entitled
"Power Module Package and Method for 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 power module package and
a method for manufacturing the same.
[0004] 2. Description of the Related Art
[0005] Recently, as electronic industries for power have been
developed, electronic products have been increasingly reduced and
have higher density. Thus, besides a method of reducing the size of
electronic elements, a method of installing elements and conducting
wires as many as possible in a determined space is a critical issue
in designing a power module package.
[0006] Meanwhile, a structure of a related art power module package
is disclosed in U.S. Pat. No. 5,920,119.
SUMMARY OF THE INVENTION
[0007] The present invention has been made in an effort to provide
a power module package and a method for manufacturing the same,
capable of eliminating or facilitating a packaging process for
coupling an external connection terminal fastening unit to a
substrate and preventing a generation of solder cracks between an
external connection terminal and a substrate to thus implement high
reliability.
[0008] According to a preferred embodiment of the present
invention, there is provided a power module package including: an
external connection terminal; a substrate in which a fastening unit
allowing one end of the external connection terminal to be
insertedly fastened thereinto is formed to penetrate in a thickness
direction thereof; and a semiconductor chip mounted on one surface
of the substrate.
[0009] The substrate may include: a metal plate; an insulating
layer formed on one surface of the metal plate; and a circuit
pattern formed on the insulating layer and including a chip to
mounting pad and an external connection pad, wherein the fastening
unit includes a portion made of a conductive material and a portion
made of a non-conductive material, wherein the fastening unit is
formed in the substrate such that the portion made of a conductive
material is in contact with the external connection pad and the
portion made of the non-conductive material is in contact with the
metal plate.
[0010] The substrate may include: a metal plate; an insulating
layer formed on one surface of the metal plate; and a circuit
pattern formed on the insulating layer and including a chip
mounting pad and an external connection pad, wherein the fastening
unit may be made of a non-conductive material and the power module
package may further include a lead frame electrically connecting
the external connection terminal to the external connection
pad.
[0011] The substrate may include: a metal plate; an insulating
layer formed on one surface of the metal plate; and a circuit
pattern formed on the insulating layer and including a chip
mounting pad and an external connection pad, wherein the fastening
unit may include a female screw made of a non-conductive material;
and a male screw made of a conductive material and having a recess
formed in a length direction to allow the external connection
terminal to be inserted thereinto, wherein the male screw may be in
contact with the external connection pad.
[0012] The fastening unit may include: an upper portion protruded
from one surface of the substrate; a central portion positioned
within the substrate; and a lower portion buried inwardly from the
other surface of the substrate in the thickness direction, wherein
a diameter of the central portion is smaller than those of the
upper and lower portions.
[0013] The power module package may further include: a case formed
on the substrate to cover one surface of the substrate and the
semiconductor chip and expose the other end of the external
connection terminal to the outside.
[0014] The power module package may further include: a sealing
member formed to cover one surface of the substrate and the
semiconductor chip within the case.
[0015] The semiconductor chip may be a power element.
[0016] According to another preferred embodiment of the present
invention, there is provided a method for manufacturing a power
module package, including: preparing a substrate having one surface
and the other surface and including a circuit pattern formed on one
surface thereof and including a chip mounting pad and an external
connection pad; forming an opening penetrating the substrate in a
thickness direction at a portion in contact with the external
connection pad in the substrate; forming a fastening unit in
contact with the external connection pad in the opening; mounting a
semiconductor chip on the chip mounting pad; and insertedly
fastening one end of the external connection terminal into the
fastening unit.
[0017] In the forming of the opening penetrating the substrate in
the thickness direction, the opening may be formed by using a laser
drill or a mechanical drill.
[0018] The forming of the fastening unit may include: inserting a
cylindrical member having a recess formed in a length direction
therein into the opening of the substrate; and pressurizing a
portion, of the cylindrical member inserted into the opening,
protruded from the surface of the substrate.
[0019] The substrate may include: a metal plate; an insulating
layer formed on one surface of the metal plate; and a circuit
pattern formed on the insulating layer and including a chip
mounting pad and an external connection pad, wherein the
cylindrical member inserted into the opening includes a portion
made of a conductive material and a portion made of a
non-conductive material, wherein the portion made of a conductive
material is in contact with the external connection pad and the
portion made of the non-conductive material is in contact with the
metal plate.
[0020] The substrate may include: a metal plate; an insulating
layer formed on one surface of the metal plate; and a circuit
pattern formed on the insulating layer and including a chip
mounting pad and an external connection pad, wherein the
cylindrical member inserted into the opening is made of a
non-conductive material, and the method may further include:
forming a lead frame for electrically connecting the external
connection terminal to the external connection pad, before the
insertedly fastening of the external connection terminal into the
fastening unit.
[0021] The forming of the fastening unit may include: mounting a
female screw in the opening; and fastening a male screw having a
recess for insertedly fastening the external connection terminal
thereon into the female screw in a length direction therein.
[0022] The female screw may be made of a non-conductive material,
and the male screw may be made of a conductive material.
[0023] The method may further include: forming a case on the
substrate such that it covers one surface of the substrate and the
semiconductor chip and exposes the other end of the external
connection terminal to the outside, after the insertedly fastening
of the external connection terminal into the fastening unit.
[0024] The method may further include: injecting a molding material
into the case to form a molding member covering one surface of the
substrate and the semiconductor chip, after the forming of the
case.
[0025] The method may further include: performing a wire bonding
process in order to electrically connect the semiconductor chip to
the circuit pattern, after the mounting of the semiconductor
chip.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] 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 which:
[0027] FIG. 1 is a cross-sectional view illustrating a structure of
a power module package according to a first embodiment of the
present invention;
[0028] FIG. 2 is a cross-sectional view illustrating a structure of
a power module package according to a second embodiment of the
present invention;
[0029] FIG. 3 is a cross-sectional view illustrating a structure of
a power module package according to a third embodiment of the
present invention;
[0030] FIGS. 4 through 11 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the first embodiment of the present invention;
[0031] FIGS. 12 through 19 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the second embodiment of the present invention;
and
[0032] FIGS. 20 through 27 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the third embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] The objects, features and advantages of the present
invention will be more clearly understood from the following
detailed description of the preferred embodiments taken in
conjunction with the accompanying drawings. Throughout the
accompanying drawings, the same reference numerals are used to
designate the same or similar components, and redundant
descriptions thereof are omitted. Further, in the following
description, the terms "first", "second", "one side", "the other
side" and the like are used to differentiate a certain component
from other components, but the configuration of such components
should not be construed to be limited by the terms. Further, in the
description of the present invention, when it is determined that
the detailed description of the related art would obscure the gist
of the present invention, the description thereof will be
omitted.
[0034] Hereinafter, preferred embodiments of the present invention
will be described in detail with reference to the attached
drawings.
[0035] Power Module Package
First Preferred Embodiment
[0036] FIG. 1 is a cross-sectional view illustrating a structure of
a power module package according to a first embodiment of the
present invention.
[0037] With reference to FIG. 1, a power module package 100
according to a first embodiment of the present invention includes
external connection terminals 130a and 130b, a substrate 110
including fastening units 140 formed to penetrate in a thickness
direction thereof, through which one end of each of the external
connection terminals 130a and 130b is insertedly fastened, and
semiconductor chips 120a and 120b mounted on one surface of the
substrate 110.
[0038] In the present embodiment, the substrate 110 may include a
metal plate 111, an insulating layer 113 formed on one surface of
the metal plate 111, and a circuit pattern 115 formed on the
insulating layer 113.
[0039] Here, the metal plate 111 may be made of a metal material
such as aluminum (Al) or an Al alloy having high thermal
conductivity, which is relatively low in price and can be easily
obtained, but the present invention is not particularly limited
thereto and any material may be employed as long as it has high
thermal conductivity.
[0040] In the present embodiment, the substrate 110 has one surface
and the other surface. Here, based on FIG. 1, one surface of the
substrate 110 may refer to a surface on which the semiconductor
chips 120a and 120b are mounted, namely, a surface on which the
circuit pattern 115 is formed, and the other surface may refer to
the opposite surface, namely, a surface from which the metal plate
111 is exposed.
[0041] In the present embodiment, the substrate 110 including the
metal plate 111, the insulating layer 113, and the circuit pattern
115 is illustrated, but the present invention is not particularly
limited thereto and, for example, the substrate may include a metal
substrate having an anode oxidation layer, a printed circuit board
(PCB), a ceramic substrate, a direct bonded copper (DBC) substrate,
and the like.
[0042] Also, in the present embodiment, as shown in FIG. 1, the
circuit pattern 115 may include a chip mounting pad 115a and an
external connection pad 115b, but the present invention is not
particularly limited thereto.
[0043] The external connection terminals 130a and 130b are
components electrically connected to an external driving IC to
drive the semiconductor chips 120a and 120b mounted on the
substrate 110. In the present embodiment, as shown in FIG. 1, the
external connection terminals 130a and 130b are formed as pin type
terminals, but the present invention is not particularly limited
thereto.
[0044] Here, the semiconductor chips 120a and 120b may be power
elements. The power elements may include a silicon controlled
rectifier (SCR), a power transistor, an insulated gate bipolar
transistor (IGBT), a MOS transistor, a power rectifier, a power
regulator, an inverter, a converter, or a high power semiconductor
chip or a diode configured by combining these elements.
[0045] In the present embodiment, a bonding layer 123 may be formed
between the semiconductor chips 120a and 120b and the chip mounting
pad 115a. In order to effectively dissipate heat, the bonding layer
123 may be made of solder or conductive epoxy having relatively
high thermal conductivity, but the present invention is not
particularly limited thereto.
[0046] Also, in the present embodiment, the semiconductor chips
120a and 120b, the substrate 110, and the external connection
terminals 130a and 130b may be electrically connected by using
wires 121, but the present invention is not particularly limited
thereto.
[0047] Here, a wire bonding process may be performed as ball
bonding, wedge bonding, and stitch bonding which are well known in
the art, but the present invention is not particularly limited
thereto.
[0048] Here, the wires 121 may be made of aluminum (Al), gold (Al),
copper (Cu), and the like, but the present invention is not
particularly limited thereto. Wires made of aluminum (Al) applying
a high rated voltage to the semiconductor chips 120a and 120b as
power elements are generally used. This is because, in order to
withstand high voltages, a thick wire is used, and here, the use of
aluminum, rather than gold (Au) or copper (Cu), is more effective
in terms of cost reduction.
[0049] In the present embodiment, the fastening units 140, allowing
the external connection terminals 130a and 130b to be insertedly
fastened therethrough, is installed to be formed to penetrate in
the thickness direction in the substrate 110.
[0050] Here, recesses 141 allowing the external connection
terminals 130a and 130b to be inserted therethrough may be formed
in a length direction within the fastening units 140.
[0051] In the present embodiment, as shown in FIG. 1, the fastening
units 140 may include an upper portion 140a and a lower portion
140c each having a saucer-like shape and a central portion 140b
having a pillar-like shape.
[0052] In detail, in the present embodiment, the fastening unit 140
may include the upper portion 140a protruded from one surface of
the substrate 110, the central portion 140b positioned within the
substrate 110, and the lower portion 140c buried inwardly from the
other surface of the substrate 110 in the thickness direction.
Here, a diameter of the central portion 140b of the fastening unit
140 may be smaller than that of the upper portion 140a and the
lower portion 140c of the fastening unit 140.
[0053] This is to fix the fastening unit 140 to the substrate 110
by forming the upper portion 140a and the lower portion 140c of the
fastening unit 140 to have a diameter greater than that of an
opening 111a formed in the substrate 110.
[0054] Also, in the present embodiment, in order to prevent the
lower portion 140c of the fastening unit 140 from being protruded
from the surface of the substrate 110, a recess portion 111b may be
formed on a corresponding portion. The recess portion 111b is
formed to be connected to the opening 111a.
[0055] Accordingly, since the lower portion 140c of the fastening
unit 140 is positioned in the recess portion 111b so as not to
protrude from the substrate 110, a heat sink may be easily attached
to the other surface of the substrate 110 in a follow-up
process.
[0056] In the present embodiment, the fastening unit 140 may
include a portion A made of a to conductive material and a portion
B made of a non-conductive material.
[0057] Namely, as shown in FIG. 1, the portion protruded from one
surface of the substrate 110 so as to be in contact with the
external connection pad 115b is made of a conductive material,
while the portion in contact with the metal plate 111, among the
components of the substrate 110, is made of a non-conductive
material in order to avoid a problem such as a short, or the
like.
[0058] Thus, without any additional component for electrically
connecting the external connection terminals 130a and 130b to the
external connection pads 115b, the external connection terminals
130a and 130b and the external connection pads 115b may be
electrically connected by the fastening units 140 made of a
conductive material.
[0059] The power module package 100 according to the present
embodiment may further include a case 160 formed on the substrate
110 to cover one surface of the substrate 110 and semiconductor
chips 120a and 120b and expose the other ends of the external
connection terminals 130a and 130b to the outside.
[0060] Here, the case 160 may include an open region 160a allowing
a molding material to be injected into the case 160
therethrough.
[0061] Also, the power module package 100 according to the present
embodiment may further include a sealing member 150 formed to cover
one surface of the substrate 110, the semiconductor chips 120a and
120b, and the wires 121 electrically connecting the semiconductor
chips 120a and 120b.
[0062] Here, a silicon gel, an epoxy molded compound (EMC), or the
like, may be used as a material of the sealing member 150, but the
present invention is not particularly limited thereto.
[0063] Also, although not shown, the power module package 100
according to the present embodiment may further include a heat sink
bonded to the other surface of the substrate 110, namely, the
exposed portion of the metal plate 111.
[0064] The heat sink may include a plurality of heat dissipation
fins for dissipating heat generated from the semiconductor chips
120a and 120b into the air.
[0065] Also, the heat sink is generally made of or coated with
copper (Cu) or tin (Sn) in order to obtain excellent heat
transmission and be easily bonded with a heat dissipation
substrate. However, the present invention is not particularly
limited thereto.
[0066] In the present embodiment, since the fastening units 140 for
insertedly fastening the external connection terminals 130a and
130b are formed to be installed in the substrate 110, a possibility
of generating cracks at the bonded interface may be prevented in
comparison to the related art in which a member for connecting an
external connection terminal is bonded to a substrate through
soldering, and thus, reliability of the product can be
enhanced.
Second Preferred Embodiment
[0067] FIG. 2 is a cross-sectional view illustrating a structure of
a power module package according to a second embodiment of the
present invention.
[0068] In the second embodiment, a description of the same
components as those of the first embodiment described above will be
omitted and the same reference numerals will be used for the same
components as those of the first embodiment.
[0069] With reference to FIG. 2, like the first embodiment, a power
module package 200 according to the present embodiment includes the
external connection terminals 130a and 130b, the substrate 110
including fastening units 240 formed to penetrate in a thickness
direction thereof, through which one end of each of the external
connection terminals 130a and 130b is insertedly fastened, and the
semiconductor chips 120a and 120b mounted on one surface of the
substrate 110.
[0070] Here, the power module package 200 may further include lead
frames 210 for electrically connecting the external connection
terminals 130a and 130b to the external connection pads 115b.
[0071] In the present embodiment, unlike the fastening units 140
according to the first embodiment, fastening units 240 are entirely
made of a non-conductive material.
[0072] The external connection terminals 130a and 130b insertedly
fastened into the fastening units 240 made of a non-conductive
material are not electrically connected to the external connection
pads 115b, so the lead frames 210 are additionally bonded to
electrically connect them.
[0073] Here, the lead frames 210 and the external connection pads
115b may be bonded by using solder or a conductive epoxy, but the
present invention is not particularly limited thereto.
[0074] Also, although not shown, holes 210a allowing the external
connection terminals 130a and 130b to penetrate therethrough may be
formed in the lead frames 210, and one end of each of the external
connection terminals 130a and 130b may be insertedly fastened into
the fastening units 240 through the holes 210a of the lead frame
210.
[0075] Here, solder or a conductive epoxy may be additionally
formed on the portions in which the external connection terminals
130a and 130b and the lead frames 210 are in contact, namely, on
the holes 210a of the lead frames 210 and the external connection
terminals 130a and 130b, to increase bonding force.
Third Preferred Embodiment
[0076] FIG. 3 is a cross-sectional view illustrating a structure of
a power module package according to a third embodiment of the
present invention.
[0077] In the third embodiment, a description of the same
components as those of the first embodiment described above will be
omitted and the same reference numerals will be used for the same
components as those of the first embodiment
[0078] With reference to FIG. 3, like the first embodiment, a power
module package 300 according to the present embodiment includes the
external connection terminals 130a and 130b, the substrate 110
including fastening units 340 formed to penetrate in a thickness
direction thereof, through which one end of each of the external
connection terminals 130a and 130b is insertedly fastened, and the
semiconductor chips 120a and 120b mounted on one surface of the
substrate 110.
[0079] In the present embodiment, as shown in FIG. 3, a fastening
unit 340 may includes a female screw 340a mounted in the opening
111a formed in the substrate 110 and a male screw 340b fastened to
the female screw 340a and having a recess 341 for an insertion of
the external connection terminal 130a or 130b formed in a length
direction therein.
[0080] Here, the female screw 340a may be made of a non-conductive
material, and the male screw 340b may be made of a conductive
material, but the present invention is not particularly limited
thereto.
[0081] However, since the female screw 340a is in direct contact
with the metal plate 111 of the substrate 110 in terms of
structure, so preferably, the female screw 340a is made of a
non-conductive material in order to prevent a short.
[0082] The male screw may be made of a conductive material so as to
electrically connect the external connection terminals 130a and
130b to the external connection pad 115b without the necessity of
an additional component for electrically connecting the external
connection terminals 130a and 130b to the external connection pad
115b.
[0083] Namely, as shown in FIG. 3, since a head portion of the male
screw 340b is in contact with the external connection pad 115b, the
external connection terminals 130a and 130b insertedly fastened
into the recess 341 of the male screw 340b made of a conductive
material may be electrically connected to the external connection
pad 115b.
[0084] Meanwhile, if the male screw 340b is made of a
non-conductive material, like the case of the foregoing second
embodiment, a component, e.g., a lead frame, for electrically
connecting the external connection terminals 130a and 130b to the
external connection pad 115b should be additionally provided.
[0085] In the present embodiment, the female screw 340a and the
male screw 340b having the recess 341 for an insertion of the
external connection terminals 130a and 130b are provided as
fastening units 340, but only the female screw 340a is provided and
a screw thread corresponding to a thread groove formed within the
female screw 340a may be formed on a portion of the external
connection terminals 130a and 130b inserted into the female screw
340a, so that the external connection terminals 130a and 130b may
be directly fastened to the male screw 340a in a screw manner.
[0086] Method for Manufacturing Power Module Package
First Preferred Embodiment
[0087] FIGS. 4 through 11 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the first embodiment of the present invention.
[0088] First, with reference to FIG. 4, the substrate 110 having a
circuit pattern 115 including a chip mounting pad 115a and an
external connection pad 115b formed on one surface thereof is
prepared.
[0089] In the present embodiment, the substrate 110 may include the
metal plate 111, the insulating layer 113 formed on one surface of
the metal plate 111, and the circuit pattern 115 formed on the
insulating layer 113, but the present invention is not particularly
limited thereto.
[0090] Here, the metal plate 111 may be made of a metal material
such as aluminum (Al) or an Al alloy, which is relatively low in
price and can be easily obtained, but the present invention is not
particularly limited thereto and any material may be employed as
long as it has high thermal conductivity.
[0091] In the present embodiment, the substrate 110 has one surface
and the other surface. Here, based on FIG. 1, one surface of the
substrate 110 may refer to a surface on which the semiconductor
chips 120a and 120b are mounted, namely, a surface on which the
circuit pattern 115 is formed, and the other surface may refer to
the opposite surface, namely, a surface from which the metal plate
111 is exposed.
[0092] Next, with reference to FIG. 5, the opening 111a penetrating
the substrate 110 in the thickness direction is formed.
[0093] In the present embodiment, the opening 111a may be formed by
using a laser drill or a mechanical drill, but the present
invention is not particularly limited thereto.
[0094] Also, in the present embodiment, as shown in FIG. 5, in
forming the opening 111a, the recess portion 111b having a diameter
greater than that of the opening 111a by a certain depth in an
inward direction may be formed on the other surface of the
substrate 110. Here, the opening 111a and the recess portion 111b
are connected into one.
[0095] Accordingly, the lower portion 140c of the fastening unit
140 is not protruded from the other surface of the substrate 110 in
forming the fastening unit 140 in a follow-up process, to thus
facilitate bonding of a heat sink to the other surface of the
substrate to enhance heat dissipation.
[0096] Thereafter, with reference to FIG. 6, a cylindrical member
125 is inserted into the opening 111a.
[0097] Here, as shown in FIG. 6, the cylindrical member 125 may
include a portion 125a made of a conductive material and a portion
125b made of a non-conductive material.
[0098] Also, a recess 125c may be formed in a length direction
within the cylindrical member 125.
[0099] And then, with reference to FIG. 7, portions, e.g., upper
and lower portions, of the cylindrical member 125 inserted into the
opening 111a, protruded from the substrate 110 are simultaneously
pressurized so as to be deformed to form the fastening unit
140.
[0100] Namely, as shown in FIG. 7, portions other than the central
portion of the cylindrical member 125 positioned in the opening
111a, namely, the portions protruded from the substrate 110, are
pressurized in the arrow direction such that they are deformed to
have a saucer-like shape having a diameter greater than that of the
central portion, thus forming the fastening unit 140 that may be
fixed in the substrate 110.
[0101] In this manner, since the opening 111a penetrating the
substrate 110 in the thickness direction is processed and then the
fastening unit 140 is formed in the opening 111a, the fastening
unit 140 may be formed in a relatively accurate position in
comparison to the related art fastening unit bonding method using
soldering.
[0102] Thus, since the fastening unit 140 may be formed relatively
in the same position in each module, external connection terminal
inserting process may also be smoothly performed.
[0103] Thereafter, with reference to FIG. 8, the semiconductor
chips 120a and 120b are mounted on the chip mounting pad 115a of
the substrate 110.
[0104] Here, the semiconductor chips 120a and 120b may be bonded to
the chip mounting pad 115a by using solder, a conductive epoxy, or
the like, but the present invention is not particularly limited
thereto.
[0105] Also, in order to electrically connect the semiconductor
chips 120a and 120b to the chip mounting pad 115a and the external
connection pad 115b on the substrate 110, wire bonding process may
be performed.
[0106] Here, the wire bonding process may include ball bonding,
wedge bonding, and stitch bonding, which are well known in the art,
but the present invention is not particularly limited thereto.
[0107] Here, the wires 121 may be made of aluminum (Al), gold (Al),
copper (Cu), and the like, but the present invention is not
particularly limited thereto. Wires made of aluminum (Al) applying
a high rated voltage to the semiconductor chips 120a and 120b as
power elements are generally used. This is because, in order to
withstand high voltages, a thick wire is used, and here, the use of
aluminum, rather than gold (Au) or copper (Cu), is more effective
in terms of cost reduction.
[0108] With reference to FIG. 9, the external connection terminals
130a and 130b are insertedly fastened into the recesses 141 formed
in a length direction within the fastening units 140.
[0109] Here, in order to enhance fastening force between the
external connection terminals 130a and 130b and the fastening units
140, a stop recess (or stop projection) (not shown) may be formed
within the recesses 141 of the fastening units 140, and a fastening
projection (or a fastening recess) (not shown) corresponding to the
stop recess (or stop projection) (not shown) may be formed on
inserted portions of the external connection terminals 130a and
130b, but the present invention is not particularly limited
thereto.
[0110] And then, with reference to FIG. 10, the case 160 is formed
on the substrate 110 with the semiconductor chips 120a and 120b
mounted thereon and the external connection terminals 130a and 130b
insertedly fastened thereinto to cover one surface of the substrate
110 and semiconductor chips 120a and 120b and expose the other ends
of the external connection terminals 130a and 130b to the
outside.
[0111] Here, the case 160 may include an open region 160a allowing
a molding material to be injected into the case 160
therethrough.
[0112] Thereafter, with reference to FIG. 11, the interior of the
case 160 is charged with a molding material through the open region
160a to form the sealing member 150 covering one surface of the
substrate 110 and the semiconductor chips 120a and 120b.
[0113] Here, a silicon gel, an epoxy molded compound (EMC), or the
like, may be used as a material of the sealing member 150, but the
present invention is not particularly limited thereto.
Second Preferred Embodiment
[0114] FIGS. 12 through 19 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the second embodiment of the present invention.
[0115] In the second embodiment, a description of the same
components as those of the first embodiment described above will be
omitted and the same reference numerals will be used for the same
components as those of the first embodiment.
[0116] With reference to FIGS. 12 to 14, after the opening 111a
penetrating the substrate 110 in the thickness direction is formed
in the substrate 110 having the circuit pattern 115 including the
chip mounting pad 115a and the external connection pad 115b, the
cylindrical member 225 having a recess 225c formed in the length
direction is inserted into the opening 111a.
[0117] Unlike the foregoing first embodiment, in the present
embodiment, the cylindrical member 225 may be entirely made of a
non-conductive material.
[0118] Next, with reference to FIG. 15, like the foregoing first
embodiment, the upper and lower portions of the cylindrical member
225 inserted into the opening 111a of the substrate 110 are
pressurized in the arrow direction so as to be deformed to form the
fastening units 240.
[0119] Thereafter, with reference to FIG. 16, the semiconductor
chips 120a and 120b are mounted on the chip mounting pad 115a, and
the lead frame 210 is bonded to the external connection pad
115b.
[0120] Here, the semiconductor chips 120a and 120b and the chip
mounting pad 115a, and the lead frame 210 and the external
connection pad 115b may be bonded by using solder or a conductive
epoxy, but the present invention is not particularly limited
thereto.
[0121] As shown in FIG. 16, a hole 210a may be formed at a central
portion between the lead frames 210 used in the present
embodiment.
[0122] The hole 210a is a portion allowing the external connection
terminals 130a and 130b to pass therethrough in a follow-up
process. The position of the hole 210a corresponds to the position
of the recess 241 of the fastening unit 240, and a diameter of the
hole 210a may be equal to that of the recess 241 of the fastening
unit 240 and those of the external connection terminals 130a and
130b, but the present invention is not particularly limited
thereto.
[0123] Thereafter, with reference to FIG. 17, one end of each of
the external connection terminals 130a and 130b is insertedly
fastened into the recess 241 of the fastening unit 240 through the
hole 210a of the lead frame 210.
[0124] Here, in order to enhance fastening force, a stop recess (or
stop projection) (not shown) may be formed within the recess 241 of
the fastening units 240, and a fastening projection (or a fastening
recess) (not shown) corresponding to the stop recess (or stop
projection) (not shown) may be formed on the external connection
terminals 130a and 130b inserted thereinto.
[0125] Thereafter, although not shown, in order to enhance bonding
force between the external connection terminals 130a and 130b and
the lead frames 210 in contact therewith, the hole 210a portions of
the lead frames 210 and the external connection terminals 130a and
130b penetrating the holes 210a may be bonded with solder or a
conductive epoxy.
[0126] Thereafter, with reference to FIGS. 18 and 19, the case 160
is formed on the substrate 110, and a molding material is injected
through the open region 160a of the case 160 to form the molding
member 150 covering one surface of the substrate and the
semiconductor chips 120a and 120b.
Third Preferred Embodiment
[0127] FIGS. 20 through 27 are cross-sectional views sequentially
illustrating a method for manufacturing a power module package
according to the third embodiment of the present invention.
[0128] In the third embodiment, a description of the same
components as those of the first embodiment described above will be
omitted and the same reference numerals will be used for the same
components as those of the first embodiment.
[0129] First, with reference to FIG. 21, an opening 311a
penetrating the substrate 110 in the thickness direction is formed
in the substrate 110 having the circuit pattern 115 including the
chip mounting pad 115a and the external connection pad 115b.
[0130] In the present embodiment, the opening 311a may be processed
by using a laser drill or a mechanical drill, but the present
invention is not particularly limited thereto.
[0131] Also, in the present embodiment, when the opening 311a is
processed, the opening 311a may be processed such that depressions
and protrusions are formed on inner walls thereof.
[0132] This is to enhance bonding force between a female screw 340a
to be insertedly mounted in the opening 311a and the substrate 110
in a follow-up process.
[0133] Also, in the present embodiment, a portion 311b connected to
the opening 311a on the other surface of the substrate 110 may be
formed to have a diameter greater than that of the opening
311a.
[0134] This is to prevent a head portion of the female screw 340a
from being protruded from the other surface of the substrate 110
when the female screw 340a, which has a head portion having a
diameter greater than that of a body portion thereof, is mounted in
the opening 311a.
[0135] Thereafter, with reference to FIG. 22, the female 340a is
mounted in the opening 311a formed in the substrate 110.
[0136] Here, spiral grooves may be formed on inner walls of the
female screw 340a.
[0137] Also, in the present embodiment, the female screw 340a may
be made of a non-conductive material, but the present invention is
not particularly limited thereto.
[0138] Here, when the substrate 110 including the metal plate 111
is used, if the female screw 340a is made of a conductive material,
a short may occur, so the female screw 340a is preferably made of a
non-conductive material.
[0139] Thereafter, with reference to FIG. 23, the male screw 340b
is coupled to the female screw 340a.
[0140] Here, the recess 341 allowing the external connection
terminals 130a and 130b to be inserted therein may be formed in a
length direction within the male screw 340b.
[0141] Also, in the present embodiment, the male screw 340b may be
made of a conductive material, but the present invention is not
particularly limited thereto.
[0142] However, when the male screw 340b is made of a conductive
material, the external connection terminals 130a and 130b may be
electrically connected to the external connection pads 115b by
insertedly fastening the external connection terminals 130a and
130b into the recesses 341 of the male screws 340b without the
necessity of a component for electrically connecting the external
connection terminals 130a and 130b to the external connection pads
115b.
[0143] Namely, as shown in FIG. 23, since the head portions of the
male screw 340b is in contact with the external connection pads
115b, the external connection terminals 130a and 130b insertedly
fastened into the recesses 341 of the male screws 340b made of a
conductive material may be electrically connected to the external
connection pads 115b.
[0144] Meanwhile, when the male screws 340b are made of a
non-conductive material, a component, for example, a lead frame, or
the like, may be additionally provided to electrically connect the
external connection terminals 130a and 130b to the external
connection pads 115b like the second embodiment as described
above.
[0145] Thereafter, with reference to FIG. 24, the semiconductor
chips 120a and 120b are mounted on the chip mounting pad 115a of
the substrate 110.
[0146] Here, the semiconductor chips 120a and 120b may be bonded to
the chip mounting pad 115a by using solder, a conductive epoxy, or
the like, but the present invention is not particularly limited
thereto.
[0147] Also, the semiconductor chips 120a and 120b may be
electrically connected to the circuit pattern 115 through wire
bonding.
[0148] Thereafter, with reference to FIG. 25, one end of each of
the external connection terminals 130a and 130b is insertedly
fastened into the recess 341 of the male screw 340b.
[0149] Here, in order to enhance fastening force, a stop recess (or
stop projection) (not shown) may be formed within the recess 341 of
the male screw 340b, and a fastening projection (or a fastening
recess) (not shown) corresponding to the stop recess (or stop
projection) (not shown) may be formed on the external connection
terminals 130a and 130b inserted thereinto.
[0150] Thereafter, with reference to FIGS. 26 and 27, the case 160
is formed on the substrate 110, and a molding material is injected
through the open region 160a of the case 160 to form the molding
member 150 covering one surface of the substrate and the
semiconductor chips 120a and 120b.
[0151] According to the preferred embodiments of the present
invention, since a process for bonding a unit for fastening an
external connection terminal to the substrate is not necessary, the
number of processes can be reduced, simplifying the processes.
[0152] Also, since the fastening unit for inserting the external
connection terminal is installed within the substrate, positions of
fastening units are relatively uniform in manufacturing respective
products, and thus, the external connection terminals can be easily
fastened.
[0153] In addition, since the fastening unit for inserting the
external connection terminal is installed in the substrate, there
is no possibility that cracks are generated in the interface of the
substrate and the fastening unit in comparison to the related art
fastening unit mounted on the substrate through soldering,
enhancing reliability of the product.
[0154] Although the embodiments of the present invention have been
disclosed for illustrative purposes, it will be appreciated that
the present invention is not limited thereto, and 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.
[0155] Accordingly, any and all 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.
* * * * *