U.S. patent application number 16/372782 was filed with the patent office on 2020-03-05 for multilayer ceramic electronic component having external electrode layers with holes.
The applicant listed for this patent is SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Hye Young CHOI, Hyun Hee GU, Eui Hyun JO, Jang Yeol LEE, Jin Woo LEE, Jong Ho LEE.
Application Number | 20200075248 16/372782 |
Document ID | / |
Family ID | 67477539 |
Filed Date | 2020-03-05 |
United States Patent
Application |
20200075248 |
Kind Code |
A1 |
CHOI; Hye Young ; et
al. |
March 5, 2020 |
MULTILAYER CERAMIC ELECTRONIC COMPONENT HAVING EXTERNAL ELECTRODE
LAYERS WITH HOLES
Abstract
A multilayer ceramic electronic component includes a ceramic
body including dielectric layers and first and second internal
electrodes alternately stacked with each of the dielectric layers
interposed therebetween. First and second external electrodes are
disposed on outer surfaces of the ceramic body, connected to the
first and second internal electrodes respectively, and disposed to
cover at least five of eight corners of the ceramic body. The first
and second external electrodes include, respectively, first and
second base electrode layers at least partially in contact with the
outer surfaces of the ceramic body and first and second plating
layers disposed to cover the first and second base electrode
layers, respectively. The first and second plating or base
electrode layers have one or more to three or less holes positioned
adjacent to one or more to three or less of the eight corners of
the ceramic body.
Inventors: |
CHOI; Hye Young; (Suwon-si,
KR) ; LEE; Jong Ho; (Suwon-si, KR) ; JO; Eui
Hyun; (Suwon-si, KR) ; LEE; Jang Yeol;
(Suwon-si,, KR) ; LEE; Jin Woo; (Suwon-si, KR)
; GU; Hyun Hee; (Suwon-si, Gyeonggi-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRO-MECHANICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Family ID: |
67477539 |
Appl. No.: |
16/372782 |
Filed: |
April 2, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
16186008 |
Nov 9, 2018 |
10373759 |
|
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16372782 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H05K 1/181 20130101;
H01G 2/065 20130101; H01G 4/232 20130101; Y02P 70/50 20151101; H05K
2201/10636 20130101; H01G 4/30 20130101; H05K 2201/10015
20130101 |
International
Class: |
H01G 4/232 20060101
H01G004/232; H01G 4/30 20060101 H01G004/30; H05K 1/18 20060101
H05K001/18 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 5, 2018 |
KR |
10-2018-0105915 |
Claims
1. A multilayer ceramic electronic component comprising: a ceramic
body including dielectric layers and first and second internal
electrodes alternately stacked in a thickness direction and
respectively exposed to opposing end surfaces of the ceramic body
with each of the dielectric layers interposed therebetween; and
first and second external electrodes disposed on outer surfaces of
the ceramic body to be connected to the first and second internal
electrodes, respectively, and disposed to cover at least five of
eight corners of the ceramic body, wherein the first and second
external electrodes include, respectively, first and second base
electrode layers at least partially in contact with the outer
surfaces of the ceramic body and first and second plating layers
disposed to cover the first and second base electrode layers,
respectively, and the first and second base electrode layers cover
at least one corner of the ceramic body, and have one or more to
three or less holes positioned closer to one of the eight corners
of the ceramic body than to the center of the ceramic body in the
thickness direction and to the center of the ceramic body in the
width direction.
2. The multilayer ceramic electronic component of claim 1, wherein
each of the first and second internal electrodes extends in a plane
extending in width and length directions, and a thickness of each
of the first and second external electrodes at a center of a
[width.times.thickness] surface is 10 .mu.m or less.
3. The multilayer ceramic electronic component of claim 2, wherein
the first and second external electrodes further include,
respectively, first and second conductive resin layers disposed
between the first and second base electrode layers and the first
and second plating layers, respectively, and at least one of the
first and second conductive resin layers covers the holes of the
first and second base electrode layers, respectively.
4. The multilayer ceramic electronic component of claim 2, wherein
at least one of the first and second plating layers covers the
holes of the first and second base electrode layers,
respectively.
5. The multilayer ceramic electronic component of claim 2, wherein
the first and second external electrodes further include,
respectively, first and second tin plating layers disposed on outer
surfaces of the first and second plating layers, respectively, and
each of the first and second plating layers contains nickel.
6. The multilayer ceramic electronic component of claim 2, wherein
an average thickness of each dielectric layer disposed between
adjacent first and second internal electrodes is 0.4 .mu.m or less,
and an average thickness of each of the first and second internal
electrodes is 0.4 .mu.m or less.
7. A multilayer ceramic electronic component comprising: a ceramic
body including alternately stacked first and second internal
electrodes with dielectric layers therebetween; and first and
second external electrodes disposed on respective opposing end
surface of the ceramic body through which the first and second
internal electrodes are respectively exposed, and extending on four
side surfaces of the ceramic body adjacent to the opposing end
surfaces, wherein the first and second external electrodes are
disposed on at least five of eight corners of the ceramic body,
each of the first and second external electrodes includes a base
electrode layer in contact with the respective end surface and the
four side surfaces of the ceramic body, and a plating layer
covering the base electrode layer, and at least one of the base
electrode layers and the plating layers of the first and second
external electrodes covers at least one corner of the ceramic body,
and includes one or more and three or less holes extending
therethrough, wherein the holes are positioned closer to one of the
eight corners of the ceramic body than to the center of the ceramic
body in the thickness direction and to the center of the ceramic
body in the width direction.
8. The multilayer ceramic electronic component of claim 7, wherein
the one or more and three of less holes are each disposed to
include therein at least one corner of the ceramic body.
9. The multilayer ceramic electronic component of claim 7, wherein
at least one of the base electrode layers and the plating layers
extends across the hole disposed in the other of the base electrode
layers and the plating layers.
10. The multilayer ceramic electronic component of claim 7, wherein
the at least one of the base electrode layers and the plating
layers having the one or more and three or less holes extending
therethrough extends over at least one respective edge between
adjacent outer surfaces of the ceramic body.
11. A multilayer ceramic electronic component comprising: a ceramic
body including dielectric layers and first and second internal
electrodes alternately stacked in a thickness direction and
respectively exposed to opposing end surfaces of the ceramic body
with each of the dielectric layers interposed therebetween; and
first and second external electrodes disposed on outer surfaces of
the ceramic body to be connected to the first and second internal
electrodes, respectively, and disposed to cover at least five of
eight corners of the ceramic body, wherein the first and second
external electrodes include, respectively, first and second base
electrode layers at least partially in contact with the outer
surfaces of the ceramic body and first and second plating layers
disposed to cover the first and second base electrode layers,
respectively, and at least one of the first and second base
electrode layers extends over at least one respective edge between
adjacent outer surfaces of the ceramic body and has one or more to
three or less holes positioned closer to one of the eight corners
of the ceramic body than to the center of the ceramic body in the
thickness direction and to the center of the ceramic body in the
width direction.
12. The multilayer ceramic electronic component of claim 11,
wherein each of the first and second internal electrodes extends in
a plane extending in width and length directions, and a thickness
of each of the first and second external electrodes at a center of
a [width.times.thickness] surface is 10 .mu.m or less.
13. The multilayer ceramic electronic component of claim 11,
wherein the first and second external electrodes further include,
respectively, first and second conductive resin layers disposed
between the first and second base electrode layers and the first
and second plating layers, respectively, and at least one of the
first and second conductive resin layers covers the holes of the at
least one of the first and second base electrode layers.
14. The multilayer ceramic electronic component of claim 11,
wherein at least one of the first and second plating layers covers
the holes of the at least one of the first and second base
electrode layers.
15. The multilayer ceramic electronic component of claim 11,
wherein the first and second external electrodes further include,
respectively, first and second tin plating layers disposed on outer
surfaces of the first and second plating layers, respectively, and
each of the first and second plating layers contains nickel.
16. The multilayer ceramic electronic component of claim 11,
wherein an average thickness of each dielectric layer disposed
between adjacent first and second internal electrodes is 0.4 .mu.m
or less, and an average thickness of each of the first and second
internal electrodes is 0.4 .mu.m or less.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is the Continuation of U.S. patent
application Ser. No. 16/186,008 filed Nov. 9, 2018, which claims
benefit of priority to Korean Patent Application No.
10-2018-0105915 filed on Sep. 5, 2018 in the Korean Intellectual
Property Office, the disclosures of which are incorporated herein
by reference in its entirety.
BACKGROUND
1. Field
[0002] The present disclosure relates to a multilayer ceramic
electronic component.
2. Description of Related Art
[0003] Multilayer ceramic electronic components are widely used as
an information technology (IT) components in computers, personal
digital assistants (PDAs), cellular phones, and the like. The
multilayer ceramic electronic components can have a small size
while implementing high capacitance, may be easily mounted, and
have been widely used as electrical components in view of their
high reliability and high durability characteristics.
[0004] An external electrode included in a multilayer ceramic
electronic component is an electrode exposed externally of the
multilayer ceramic electronic component, and has a significant
influence on reliability and durability of the multilayer ceramic
electronic component.
[0005] Recently, in accordance with miniaturization and
functionality improvements of multilayer ceramic electronic
components, a thickness of external electrodes has gradually
decreased. However, as the thickness of external electrodes is
decreased, reliability and durability of the external electrode may
also be decreased.
SUMMARY
[0006] As a thickness of an external electrode is decreased, a
plating layer and/or a base electrode layer included in the
external electrode may have holes positioned at points
corresponding to eight corners of a ceramic body.
[0007] An aspect of the present disclosure may provide a multilayer
ceramic electronic component in which a thickness of the external
electrode may be decreased and deterioration of water proof
reliability and a mounting defective rate of the external electrode
may be substantially suppressed, by optimizing the number of
holes.
[0008] According to an aspect of the present disclosure, a
multilayer ceramic electronic component may include a ceramic body
including dielectric layers and first and second internal
electrodes alternately stacked in a thickness direction and
respectively exposed to one opposing surfaces of the ceramic body
with each of the dielectric layers interposed therebetween. First
and second external electrodes are disposed on outer surfaces of
the ceramic body to be connected to the first and second internal
electrodes, respectively, and disposed to cover at least five of
eight corners of the ceramic body. The first and second external
electrodes include, respectively, first and second base electrode
layers at least partially in contact with the outer surfaces of the
ceramic body and first and second plating layers disposed to cover
the first and second base electrode layers, respectively. The first
and second plating layers have one or more to three or less holes
positioned adjacent to one or more to three or less of the eight
corners of the ceramic body.
[0009] According to another aspect of the present disclosure, a
multilayer ceramic electronic component may include a ceramic body
including dielectric layers and first and second internal
electrodes alternately stacked in a thickness direction and
respectively exposed to opposing end surfaces of the ceramic body
with each of the dielectric layers interposed therebetween. First
and second external electrodes are disposed on outer surfaces of
the ceramic body to be connected to the first and second internal
electrodes, respectively, and disposed to cover at least five of
eight corners of the ceramic body. The first and second external
electrodes include, respectively, first and second base electrode
layers at least partially in contact with the outer surfaces of the
ceramic body and first and second plating layers disposed to cover
the first and second base electrode layers, respectively. The first
and second base electrode layers have one or more to three or less
holes positioned adjacent to the eight corners of the ceramic
body.
[0010] According to a further aspect of the present disclosure, a
multilayer ceramic electronic component may include a ceramic body
including alternately stacked first and second internal electrodes
with dielectric layers therebetween, and first and second external
electrodes disposed on respective opposing end surface of the
ceramic body through which the first and second internal electrodes
are respectively exposed, and extending on four side surfaces of
the ceramic body adjacent to the opposing end surfaces. The first
and second external electrodes are disposed on at least five of
eight corners of the ceramic body. Each of the first and second
external electrodes includes a base electrode layer in contact with
the respective end surface and the four side surfaces of the
ceramic body, and a plating layer covering the base electrode
layer, and at least one of the base electrode layers and the
plating layers of the first and second external electrodes includes
one or more and three or less holes extending therethrough.
BRIEF DESCRIPTION OF DRAWINGS
[0011] The above and other aspects, features, and advantages of the
present disclosure will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0012] FIG. 1 is a perspective view illustrating a multilayer
ceramic electronic component according to an exemplary
embodiment;
[0013] FIG. 2 is a cross-sectional view taken along line A-A' of
FIG. 1;
[0014] FIG. 3 is an enlarged view of region S of FIG. 2;
[0015] FIG. 4 is a perspective view illustrating corners of the
multilayer ceramic electronic component according to an exemplary
embodiment;
[0016] FIG. 5 is a perspective view illustrating a multilayer
ceramic electronic component according to an exemplary embodiment
that is mounted on a board;
[0017] FIG. 6A shows images, captured by a scanning electron
microscope (SEM), of a multilayer ceramic electronic component that
has holes disposed at corners; and
[0018] FIG. 6B shows images, captured by an SEM, of a multilayer
ceramic electronic component that does not have holes disposed at
corners.
DETAILED DESCRIPTION
[0019] Hereinafter, exemplary embodiments will now be described in
detail with reference to the accompanying drawings.
[0020] Directions of a hexahedron will be defined in order to
clearly describe exemplary embodiments in the present disclosure.
L, W and T illustrated in the drawings refer to a length direction,
a width direction, and a thickness direction, respectively. Here,
the thickness direction refers to a stacking direction in which
dielectric layers are stacked.
[0021] A multilayer ceramic electronic component according to an
exemplary embodiment, particularly a multilayer ceramic capacitor,
will hereinafter be described. However, the multilayer ceramic
electronic component according to the present disclosure is not
limited thereto.
[0022] FIG. 1 is a perspective view illustrating a multilayer
ceramic electronic component according to an exemplary embodiment,
FIG. 2 is a cross-sectional view taken along line A-A' of FIG. 1,
and FIG. 3 is an enlarged view of region S of FIG. 2.
[0023] Referring to FIGS. 1 through 3, a multilayer ceramic
electronic component 100 according to an exemplary embodiment may
include a ceramic body 110, and first and second external
electrodes 131 and 132.
[0024] The ceramic body 110 may be formed of a hexahedron having
end surfaces opposite each other in a length direction L, side
surfaces opposite each other in a width direction W, and side
surfaces opposite each other in a thickness direction T. The
ceramic body 110 may be formed by stacking a plurality of
dielectric layers 111 in the thickness direction T and then
sintering the plurality of dielectric layers 111. A shape and a
dimension of the ceramic body 110 and the number (one or more) of
stacked dielectric layers 111 are not limited to those illustrated
in the present exemplary embodiment.
[0025] The plurality of dielectric layers 111 disposed in the
ceramic body 110 may be in a sintered state, and adjacent
dielectric layers 111 may be integrated with each other so that
boundaries therebetween are not readily apparent without using a
scanning electron microscope (SEM).
[0026] The ceramic body 110 may have a form in which eight corners
of the hexahedron are round. Therefore, durability and reliability
of the ceramic body 110 may be improved, and structural reliability
of the first and second external electrodes 131 and 132 at the
corners may be improved.
[0027] The dielectric layers 111 may have a thickness arbitrarily
changed in accordance with a capacitance design of the multilayer
ceramic electronic component 100, and may include ceramic powders
having a high dielectric constant, such as barium titanate
(BaTiO.sub.3)-based powders or strontium titanate
(SrTiO.sub.3)-based powders. However, a material of the dielectric
layer 111 according to the present disclosure is not limited
thereto. In addition, various ceramic additives, organic solvents,
plasticizers, binders, dispersants, and the like, may be added to
the ceramic powders according to an object of the present
disclosure.
[0028] An average particle size of the ceramic powders used to form
the dielectric layer 111 is not particularly limited, and may be
controlled in order to accomplish an object of the present
disclosure. For example, the average particle size of the ceramic
powders used to form the dielectric layer 111 may be controlled to
be 400 nm or less. Therefore, the multilayer ceramic electronic
component 100 according to an exemplary embodiment in the present
disclosure may be used as a component that can be miniaturized and
have a high capacitance, such as an information technology (IT)
component.
[0029] For example, the dielectric layers 111 may be formed by
applying and then drying slurry including powders such as barium
titanate (BaTiO.sub.3) powders, or the like, to carrier films to
prepare a plurality of ceramic sheets. The ceramic sheets may be
formed by mixing ceramic powders, a binder, and a solvent with one
another to prepare slurry and manufacturing the slurry in a sheet
shape having a thickness of several micrometers by a doctor blade
method, but are not limited thereto.
[0030] First and second internal electrodes 121 and 122 may include
at least one first internal electrode 121 and at least one second
internal electrode 122 having different polarities, and may be
formed at predetermined thicknesses with each of the plurality of
dielectric layers 111 stacked in the thickness direction T of the
ceramic body 110 interposed therebetween.
[0031] The first internal electrodes 121 and the second internal
electrodes 122 may be formed to be respectively exposed to one end
surface and the other end surface of the ceramic body 110 in the
length direction L of the ceramic body 110 in the stack direction
of the dielectric layers 111 by printing a conductive paste
including a conductive metal, and may be electrically insulated
from each other by each of the dielectric layers 111 disposed
therebetween. The first internal electrodes 121 and the second
internal electrodes 122 may be alternately stacked with the
dielectric layers 111 therebetween in the ceramic body 110.
[0032] That is, the first and second internal electrodes 121 and
122 may be electrically connected to the first and second external
electrodes 131 and 132, respectively, formed on opposite end
surfaces of the ceramic body 110 in the length direction L of the
ceramic body 110 through portions alternately exposed to the
opposite end surfaces of the ceramic body 110 in the length
direction of the ceramic body 110.
[0033] For example, the first and second internal electrodes 121
and 122 may include metal powders having an average particle size
of 0.1 to 0.2 .mu.m, and may be formed of a conductive paste for an
internal electrode including 40 to 50 wt % of conductive metal
powders, but are not limited thereto.
[0034] The conductive paste for an internal electrode may be
applied to the ceramic sheets by a printing method, or the like, to
form internal electrode patterns. A method of printing the
conductive paste may be a screen printing method, a gravure
printing method, or the like, but is not limited thereto. Two
hundred or three hundred ceramic sheets on which the internal
electrode patterns are printed may be stacked, pressed, and
sintered to manufacture the ceramic body 110.
[0035] Therefore, when voltages are applied to the first and second
external electrodes 131 and 132, electric charges may be
accumulated between the first and second internal electrodes 121
and 122 facing each other. In this case, a capacitance of the
multilayer ceramic capacitor 100 may be in proportion to an area of
a region in which the first and second internal electrodes 121 and
122 overlap each other.
[0036] That is, when the area of the region in which the first and
second internal electrodes 121 and 122 overlap each other is
significantly increased, a capacitance may be significantly
increased even in a capacitor having the same size.
[0037] Widths of the first and second internal electrodes 121 and
122 may be determined depending on the purpose, and may be, for
example, 0.4 .mu.m or less. Therefore, the multilayer ceramic
electronic component 100 according to an exemplary embodiment in
the present disclosure may be used as a component that can be
miniaturized and have a high capacitance, such as an information
technology (IT) component.
[0038] Since the thickness of the dielectric layer 111 corresponds
to an interval between the first and second internal electrodes 121
and 122, the smaller the thickness of the dielectric layer 111, the
greater the capacitance of the multilayer ceramic electronic
component 100.
[0039] Meanwhile, the conductive metal included in the conductive
paste forming the first and second internal electrodes 121 and 122
may be nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), lead
(Pb), or platinum (Pt), or alloys thereof. However, the conductive
metal according to the present disclosure is not limited
thereto.
[0040] The first and second external electrodes 131 and 132 may be
disposed on outer surfaces of the ceramic body 110 to be connected
to the first and second internal electrodes 121 and 122,
respectively. The first external electrode 131 may be configured to
electrically connect the first internal electrodes 121 and a board
to each other, and the second external electrode 132 may be
configured to electrically connect the second internal electrodes
122 and the board to each other.
[0041] The first and second external electrodes 131 and 132 may
include, respectively, first and second plating layers 131c and
132c for the purpose of at least a portion of structural
reliability, easiness in mounting the multilayer ceramic electronic
component on the board, durability against external impact, heat
resistance, and an equivalent series resistance (ESR).
[0042] For example, the first and second plating layers 131c and
132c may be formed by sputtering or electric deposition, but are
not limited thereto.
[0043] For example, the first and second plating layers 131c and
132c may mainly contain nickel, but are not limited thereto, and
may also be implemented by copper (Cu), palladium (Pd), platinum
(Pt), gold (Au), silver (Ag), or lead (Pb), or alloys thereof.
[0044] The first and second external electrodes 131 and 132 may
further include, respectively, first and second base electrode
layers 131a and 132a disposed between the first and second internal
electrodes 121 and 122 and the first and second plating layers 131c
and 132c, respectively, and at least partially in contact with the
outer surfaces of the ceramic body 110.
[0045] The first and second base electrode layers 131a and 132a may
be relatively easily coupled to the first and second internal
electrodes 121 and 122, respectively, as compared to the first and
second plating layers 131c and 132c, and may thus decrease contact
resistances against the first and second internal electrodes 121
and 122.
[0046] The first and second base electrode layers 131a and 132a may
be disposed in inner regions relative to the first and second
plating layers 131c and 132c in the first and second external
electrodes 131 and 132, respectively.
[0047] For example, the first and second base electrode layers 131a
and 132a may be covered (e.g., fully covered) by the first and
second plating layers 131c and 132c and first and second conductive
resin layers 131b and 132b, respectively, so as not to be exposed
externally of the multilayer ceramic electronic component 100.
[0048] For example, the first and second base electrode layers 131a
and 132a may be formed by a method of dipping the ceramic body 110
in a paste including a metal component or a method of printing a
conductive paste including a conductive metal on at least one
surface of the ceramic body 110 in the thickness direction T, and
may also be formed by a sheet transfer method or a pad transfer
method.
[0049] For example, the first and second base electrode layers 131a
and 132a may be formed of copper (Cu), nickel (Ni), palladium (Pd),
platinum (Pt), gold (Au), silver (Ag), or lead (Pb), or alloys
thereof.
[0050] The first and second external electrodes 131 and 132 may
further include, respectively, the first and second conductive
resin layers 131b and 132b disposed between the first and second
base electrode layers 131a and 132a and the first and second
plating layers 131c and 132c, respectively.
[0051] Since the first and second conductive resin layers 131b and
132b have relatively high flexibility as compared to the first and
second plating layers 131c and 132c, the first and second
conductive resin layers 131b and 132b may protect the multilayer
ceramic electronic component 100 from external physical impact or
warpage impact of the multilayer ceramic electronic component 100,
and may absorb stress applied to the external electrodes at the
time of mounting the multilayer ceramic electronic component on the
board or tensile stress to prevent a crack from being generated in
the external electrodes.
[0052] For example, the first and second conductive resin layers
131b and 132b may have high flexibility and high conductivity by
having a structure in which conductive particles such as copper
(Cu), nickel (Ni), palladium (Pd), platinum (Pt), gold (Au), silver
(Ag), or lead (Pb), are contained in a glass or a resin having high
conductivity, such as an epoxy resin.
[0053] The first and second external electrodes 131 and 132 may
further include, respectively, first and second tin plating layers
131d and 132d disposed on outer surfaces of the first and second
plating layers 131c and 132c, respectively. The first and second
tin plating layers 131d and 132d may further improve at least a
portion of the structural reliability, the easiness in mounting the
multilayer ceramic electronic component on the board, the
durability against the external impact, the heat resistance, and
the ESR.
[0054] FIG. 4 is a perspective view illustrating corners of the
multilayer ceramic electronic component according to an exemplary
embodiment.
[0055] Referring to FIG. 4, the ceramic body 110 may include eight
corners including corners P1, P1-2, P1-3, and P1-4.
[0056] The first and second plating layers 131c and 132c may be
disposed to cover the eight corners including corners P1, P1-2,
P1-3, and P1-4 of the ceramic body 110.
[0057] Each of the first and second plating layers 131c and 132c
may have a thickness deviation.
[0058] For example, each of the first and second plating layers
131c and 132c may have the greatest thickness at the center of a
[width.times.thickness] surface, and may have the smallest
thickness at points thereof corresponding to the eight corners
including corners P1, P1-2, P1-3, and P1-4.
[0059] Therefore, when an average thickness of each of the first
and second plating layers 131c and 132c is gradually decreased,
holes may be formed or occur at the points of the first and second
plating layers 131c and 132c corresponding to the eight corners
including corners P1, P1-2, P1-3, and P1-4. For example, holes may
occur at points adjacent to, aligned with, or overlapping with the
eight corners including corners P1, P1-2, P1-3, and P1-4. For
instance, holes in close proximity to the eight corners including
corners P1, P1-2, P1-3, and P1-4 may occur, such as holes disposed
at a distance from a respective corner that is less than 10%, less
than 5%, or less than 2% of a length of a side of the body of the
multilayer component. The holes may overlap with or include the
corners, such that corners are exposed through the holes.
[0060] The smaller the average thickness of each of the first and
second plating layers 131c and 132c, the greater the likely size of
each of the holes.
[0061] As the average thickness of each of the first and second
plating layers 131c and 132c become small, the first and second
plating layers 131c and 132c may improve reliability and warpage
endurance of the multilayer ceramic electronic component against a
cost of the multilayer ceramic electronic component.
[0062] The holes formed as the thickness of each of the first and
second plating layers 131c and 132c becomes small may serve as an
external moisture permeation path to decrease moistureproof
reliability of the multilayer ceramic electronic component and
decrease mounting reliability of the multilayer ceramic electronic
component.
[0063] Therefore, when the thickness of each of the first and
second plating layers 131c and 132 is optimized, the first and
second plating layers 131c and 132c may not only secure the
reliability and the warpage endurance of the multilayer ceramic
electronic component against the cost of the multilayer ceramic
electronic component, but may also secure the moistureproof
reliability and the mounting reliability.
[0064] Since each of the first and second plating layers 131c and
132c may have a thickness deviation at the points thereof
corresponding to the eight corners including corners P1, P1-2,
P1-3, and P1-4, when the thickness of each of the first and second
plating layers 131c and 132c is controlled so that holes are formed
at only points of each of the first and second plating layers 131c
and 132c corresponding to (e.g., aligned with, or overlapping with)
some of the eight corners including corners P1, P1-2, P1-3, and
P1-4 at the time of forming the first and second plating layers
131c and 132c, the thickness of each of the first and second
plating layers 131c and 132c may be optimized.
[0065] Table 1 represents mounting reliability and moistureproof
reliability depending on a frequency of hole forming at one of the
eight corners including corners P1, P1-2, P1-3, and P1-4.
TABLE-US-00001 TABLE 1 Mounting Hole Forming Defect Moistureproof
Reliability Frequency Frequency Defect Frequency Number of Times of
Measurement Design No. 10 400 400 1 10 87 112 2 9 64 88 3 9 66 93 4
7 33 48 5 6 9 51 6 6 3 5 7 5 1 0 8 3 0 0 9 2 0 0 10 0 0 0
[0066] Referring to Table 1, when a hole forming frequency is less
than 50%, a mounting defect and a moistureproof reliability defect
may be prevented.
[0067] That is, when the thickness of each of the first and second
plating layers 131c and 132c is controlled so that each of the
first and second plating layers 131c and 132c has one or more to
three or less holes positioned at the points thereof corresponding
to the eight corners including corners P1, P1-2, P1-3, and P1-4,
the mounting defect and the moistureproof reliability defect may be
prevented.
[0068] For example, a thickness of each of the first and second
external electrodes 131 and 132 at the center of the
[width.times.thickness] surface may be controlled to be 101 .mu.m
or less.
[0069] Therefore, in the multilayer ceramic electronic component
according to an exemplary embodiment, the reliability and the
warpage endurance of the multilayer ceramic electronic component
against the cost of the multilayer ceramic electronic component as
well as the moistureproof reliability and the mounting reliability
may be secured.
[0070] For example, a thickness of each of the first and second
plating layers 131c and 132c at the center of the
[width.times.thickness] surface may be controlled to be 3 .mu.m or
more to 5 .mu.m or less.
[0071] Therefore, in the multilayer ceramic electronic component
according to an exemplary embodiment, the reliability and the
warpage endurance of the multilayer ceramic electronic component
against the cost of the multilayer ceramic electronic component as
well as the moistureproof reliability and the mounting reliability
may be secured.
[0072] The first and second conductive resin layers 131b and 132b
may be exposed through and extend across the holes in the first and
second plating layers 131c and 132c, respectively. Therefore,
durability of the multilayer ceramic electronic component according
to an exemplary embodiment against external physical impact or
warpage impact of the multilayer ceramic electronic component 100
may not be substantially deteriorated.
[0073] Meanwhile, in the multilayer ceramic electronic component
according to an exemplary embodiment, the moistureproof reliability
and the mounting reliability as well as the reliability and the
warpage endurance of the multilayer ceramic electronic component
against the cost of the multilayer ceramic electronic component may
be secured by optimizing a thickness of each of the first and
second base electrode layers 131a and 132a illustrated in FIGS. 1
through 3 instead of the first and second plating layers 131c and
132c.
[0074] The reason is that each of the first and second base
electrode layers 131a and 132a may also have a thickness deviation
due to fluidity and viscosity in a process of being formed, similar
to the thickness deviation of each of the first and second plating
layers 131c and 132c.
[0075] That is, the first and second base electrode layers 131a and
132a may have one or more to three or less holes positioned at one
or more to three or less of eight points of the first and second
base electrode layers 131a and 132a closest to the eight corners
including corners P1, P1-2, P1-3, and P1-4 of the ceramic body 110.
For example, holes may occur at points adjacent to, aligned with,
or overlapping with the eight corners including corners P1, P1-2,
P1-3, and P1-4. For instance, holes in close proximity to the eight
corners including corners P1, P1-2, P1-3, and P1-4 may occur, such
as holes disposed at a distance from a respective corner that is
less than 10%, less than 5%, or less than 2% of a length of a side
of the body of the multilayer component. The holes may overlap with
or include the corners, such that corners are exposed through the
holes
[0076] Meanwhile, in the multilayer ceramic electronic component
according to an exemplary embodiment, the thickness of each of the
first and second external electrodes 131 and 132 may further be
decreased and the moistureproof reliability and the mounting
reliability may be secured by optimizing both of the thickness of
the first and second plating layers 131c and 132c and the thickness
of each of the first and second base electrode layers 131a and
132a.
[0077] That is, some of the eight corners including corners P1,
P1-2, P1-3, and P1-4 of the ceramic body 110 may be exposed through
holes of the first and second external electrodes 131 and 132.
[0078] Here, the first and second tin plating layers 131d and 132d
may cover the holes through which the ceramic body 110 is exposed.
Depending on a design, the first and second conductive resin layers
131b and 132b may additionally cover the holes through which the
ceramic body 110 is exposed.
[0079] FIG. 5 is a perspective view illustrating a form in which
the multilayer ceramic electronic component according to an
exemplary embodiment is mounted.
[0080] Referring to FIG. 5, the multilayer ceramic electronic
component 100 according to an exemplary embodiment may include
first and second solders 230 connected, respectively, to the first
and second external electrodes 131 and 132 to be electrically
connected to a board 210.
[0081] For example, the board 210 may include first and second
electrode pads 221 and 222, and the first and second solders 230
may be disposed on the first and second electrode pads 221 and 222,
respectively.
[0082] When corners of the ceramic body 110 are round, the first
and second solders 230 may be filled in surplus spaces depending on
the round corners of the ceramic body 110.
[0083] The first and second solders 230 may be more closely coupled
to the first and second external electrodes 131 and 132,
respectively, in a reflow process, and the multilayer ceramic
electronic component 100 according to an exemplary embodiment may
not only have the first and second external electrodes 131 and 132
that are relatively thin, but may also have the mounting
reliability, such that a disconnection of the first and second
solders 230 in the reflow process may be prevented.
[0084] FIG. 6A shows images, captured by a scanning electron
microscope (SEM), of a multilayer ceramic electronic component that
has holes disposed at corners and extending through an external
electrode. In contrast, FIG. 6B shows images, captured by an SEM,
of a multilayer ceramic electronic component that does not have
holes extending through all layers of an external electrode at
corners thereof.
[0085] As set forth above, in the multilayer ceramic electronic
component according to an exemplary embodiment, the thickness of
the external electrode may be decreased and deterioration of
moistureproof reliability and a mounting defective rate of the
external electrode may be substantially suppressed, by optimizing
the number of holes of the plating layer and/or the base electrode
layer.
[0086] While exemplary embodiments have been shown and described
above, it will be apparent to those skilled in the art that
modifications and variations could be made without departing from
the scope of the present invention as defined by the appended
claims.
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