U.S. patent application number 15/687913 was filed with the patent office on 2017-12-14 for electronic component having multilayer structure and method of manufacturing the same.
The applicant listed for this patent is SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Sung Hun CHO, Won Sik CHONG, Chang Ho LEE.
Application Number | 20170358396 15/687913 |
Document ID | / |
Family ID | 55655931 |
Filed Date | 2017-12-14 |
United States Patent
Application |
20170358396 |
Kind Code |
A1 |
CHO; Sung Hun ; et
al. |
December 14, 2017 |
ELECTRONIC COMPONENT HAVING MULTILAYER STRUCTURE AND METHOD OF
MANUFACTURING THE SAME
Abstract
An electronic component of a multi-layered structure includes a
laminate formed by stacking a plurality of ceramic bodies and an
external electrode made of a conductive resin for connecting each
ceramic body.
Inventors: |
CHO; Sung Hun; (Suwon-si,
KR) ; LEE; Chang Ho; (Seoul, KR) ; CHONG; Won
Sik; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRO-MECHANICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Family ID: |
55655931 |
Appl. No.: |
15/687913 |
Filed: |
August 28, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14876774 |
Oct 6, 2015 |
|
|
|
15687913 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01G 4/385 20130101;
H01G 4/2325 20130101; H01G 4/1227 20130101; H01G 4/30 20130101;
H01G 4/012 20130101 |
International
Class: |
H01G 4/38 20060101
H01G004/38; H01G 4/012 20060101 H01G004/012; H01G 4/232 20060101
H01G004/232; H01G 4/30 20060101 H01G004/30 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 8, 2014 |
KR |
10-2014-0136068 |
Claims
1. An electronic component comprising: a laminate formed by
stacking a plurality of ceramic bodies; and an external electrode
made of a conductive resin for connecting each ceramic body.
2. The electronic component according to claim 1, further
comprises: an adhesive for adhering between the ceramic bodies.
3. The electronic component according to claim 1, wherein the
ceramic bodies are multi-layered ceramic capacitors (MLCC).
4. The electronic component according to claim 3, wherein each of
the multi-layered ceramic capacitors has an inner electrode
structure different from each other.
5. The electronic component according to claim 3, wherein each of
the multi-layered ceramic capacitors has an electrostatic capacity
different from each other.
6. The electronic component according to claim 1, further
comprising a metal layer plated on the external electrode.
7. An electronic component comprising: a laminate formed by
stacking a plurality of different types of multi-layered ceramic
capacitors; and an external electrode made of a conductive resin
for connecting each ceramic body, wherein the multi-layered ceramic
capacitors is selected from a group consisting of a normal
structure multi-layered ceramic capacitor, an open structure
multi-layered ceramic capacitor, a thick & horizontally mounted
capacitor (T-HMC) structure multi-layered ceramic capacitors, a
float structure multi-layered ceramic capacitor, a T-HMC-open
structure multi-layered ceramic capacitor, and a T-HMC-Float
structure multi-layered ceramic capacitor.
8. The electronic component according to claim 7, wherein the
multi-layered ceramic capacitor arranged at a most bottom of the
laminate is one of an open structure multi-layered ceramic
capacitor, a T-HMC structure multi-layered ceramic capacitors, a
float structure multi-layered ceramic capacitor, a T-HMC-open
structure multi-layered ceramic capacitor, and a T-HMC-Float
structure multi-layered ceramic capacitor.
9. The electronic component according to claim 8, wherein the
remaining multi-layered ceramic capacitor except a lowermost
multi-layered ceramic capacitor is the normal structure
multi-layered ceramic capacitor.
10. The electronic component according to claim 9, wherein the
normal structure multi-layered ceramic capacitor is formed of at
least two.
11. The electronic component according to claim 7, further
comprises: an adhesive for adhering between the multi-layered
ceramic capacitors.
12. The electronic component according to claim 7, further
comprises: a metal layer plated on a surface of the external
electrode.
13. A method of manufacturing an electronic component comprising:
preparing a plurality of different multi-layered ceramic
capacitors; stacking the plurality of multi-layered ceramic
capacitors; and forming external terminals made of a conductive
resin on opposite ends of a laminate obtained by stacking the
plurality of multi-layered ceramic capacitors.
14. The method of manufacturing the electronic component according
to claim 13, wherein, in the stacking the plurality of
multi-layered ceramic capacitors, any one of the multi-layered
ceramic capacitors selected from an open structure, a T-HMC
structure, a float structure, a T-HMC-open structure, a T-HMC-float
structure is arranged at a lowermost surface.
15. The method of manufacturing the electronic component according
to claim 14, wherein the normal structure multi-layered ceramic
capacitor is stacked on a top of the lowermost multi-layered
ceramic capacitor.
16. The method of manufacturing the electronic component according
to claim 13, wherein, in the stacking the plurality of
multi-layered ceramic capacitors, after any one of the
multi-layered ceramic capacitors selected from an open structure, a
T-HMC structure, a float structure, a T-HMC-open structure, a
T-HMC-float structure is arranged at a lowermost surface, a
multi-layered ceramic capacitor having a structure different from
the lowermost multi-layered ceramic capacitor among the T-HMC
structure, the float structure, the T-HMC-open structure and the
T-HMC-float structure is stacked and a normal structure
multi-layered ceramic capacitor is stacked on an uppermost
surface.
17. The method of manufacturing the electronic component according
to claim 13, wherein, when the plurality of multi-layered ceramic
capacitors are stacked, after an adhesive resin is coated between
the multi-layered ceramic capacitors, it is cured.
18. The method of manufacturing the electronic component according
to claim 13, wherein forming the external terminals is performed by
sintering after coating a conductive paste on opposite ends of the
laminate.
19. An electronic component comprising: a laminate including a
plurality of ceramic bodies stacking one on another and one or more
adhesive layers interposed therebetween, each ceramic body
including a plurality of first internal electrodes exposed to one
end of the laminate and a plurality of second internal electrodes
exposed to another end of the laminate, and the first and second
internal electrodes of ceramic bodies including a first boundary
internal electrode and a second boundary internal electrode,
wherein all the other first and second internal electrodes of the
ceramic bodies are interposed between the first and second boundary
internal electrodes; a first external electrode formed of a
conductive resin on the one end of the laminate and electrically
connected to the plurality of first internal electrodes of the
plurality of ceramic bodies; and a second external electrode formed
of the conductive resin on the other end of the laminate and
electrically connected to the plurality of second internal
electrodes of the plurality of ceramic bodies.
20. The electronic component of claim 19, wherein a dielectric
material interposed between the internal electrodes of the same
ceramic body is different from a material forming the one or more
adhesive layers.
21. The electronic component of claim 20, wherein the dielectric
material is piezoelectric or electrostrictive.
22. The electronic component of claim 19, further comprising a
metal layer plated on each external electrode.
23. The electronic component of claim 19, wherein a width of each
internal electrode of the ceramic body which the first boundary
internal electrode belongs to, determined in a direction from the
first external electrode to the second external electrode, is less
than that of any other internal electrodes.
24. The electronic component of claim 19, wherein: in a vertical
direction along which the ceramic bodies stack, each internal
electrode of the ceramic body which the first boundary internal
electrode belongs to, overlaps with extension portions of only one
of the first and second external electrodes, and in the vertical
direction, each internal electrode of the ceramic body or the
ceramic bodies which the first boundary internal electrode does not
belong to, overlaps with the extension portions of both of the
first and second external electrodes.
25. The electronic component of claim 19, wherein: the ceramic
body, which the first boundary internal electrode belongs to,
includes a plurality of floating internal electrodes not
electrically connected to any of the first and second external
electrodes, and in the ceramic body, which the first boundary
internal electrode belongs to, one of the first internal electrodes
and one of the second internal electrodes are formed on a same
plane.
26. The electronic component of claim 25, wherein in a vertical
direction along which the ceramic bodies stack, each internal
electrode of the ceramic body or the ceramic bodies, which the
first boundary internal electrode does not belong to, overlaps with
extension portions of both of the first and second external
electrodes.
27. The electronic component of claim 19, wherein a capacitance of
the ceramic body which the first boundary internal electrode
belongs to, is less than a capacitance of each remaining ceramic
body.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation patent application of
U.S. patent application Ser. No. 14/876,774, filed on Oct. 6, 2015
which claims priority to Korean Patent Application No.
10-2014-0136068, filed on Oct. 8, 2014 in the Korean Intellectual
Property Office, which are hereby incorporated by reference in
their entireties into this application.
TECHNICAL FIELD
[0002] The present disclosure relates to an electronic component,
and, more particularly, to an electronic component of a stack type
structure formed by stacking a plurality of capacitor devices and a
method of fabricating the same.
BACKGROUND
[0003] In general, a multi-layered ceramic capacitor (MLCC) has a
structure that an inner electrode is stacked between a plurality of
ceramic sheets as a chip type condenser capable of playing an
important role of charging or discharging electric charges by being
mounted on a printed circuit board of various electronic appliances
such as a mobile communication terminal, a notebook, a computer, a
personal digital assistants (PDA).
[0004] Such a multi-layered ceramic capacitor has been widely used
for various electronic appliances due to the advantage that it is
easily mounted with implementing compactness. Particularly, in
recent, the capacitor with a large capacity is required according
to the trends of high performance and multi-function of the
electronic appliances.
[0005] Although the most general method for increasing the
capacitance of the multi-layered ceramic capacitor is to increase
the number of stacked internal electrodes, if the number of inner
electrodes increases, the failure such as a crack or a delamination
is easily generated due to the large step with a margin part during
a stacking process.
[0006] As another method for increasing the capacitance, Japanese
patent publication No. 2000-195753 discloses a stack type structure
capacitor that a laminate is formed by stacking a plurality of
capacitor devices in a vertical direction and lead terminals made
of a metal material are formed on opposite ends of the laminate so
as to electrically connect each of the capacitor devices.
[0007] However, since a conventional dielectric material to form
the multi-layered ceramic capacitor, e.g., barium titanate, has the
properties of piezoelectric and electrostrictive, vibration is
generated due to the piezoelectric effect during the application of
voltage, and according to the structure suggested in Japanese
patent publication No. 2000-195753, the vibration generated in the
laminate is transmitted to the substrate through the lead
terminals. Since the substrate is operated as an acoustic
transducer, the vibration transmitted to the substrate causes
acoustic noise.
SUMMARY
[0008] The present invention has been invented in order to overcome
the above-described problems and it is, therefore, an object of the
present invention to provide an electronic component capable of
improving a bending strength and a thermal shock by forming
external electrodes with strong impact resistance on opposite ends
of the stack type capacitor laminate, increasing the reliability by
reducing the acoustic noise and suppressing the generations of
short and crack as well as implementing the high capacitance by
discriminating the usage of the capacitor forming the laminate.
[0009] In accordance with a first embodiment of the present
invention to achieve the object, there is provided an electronic
component capable of absorbing the vibration due to the dielectric
and the impact applied from outside by forming the external
electrodes equipped on opposite ends of the laminate with a
conductive resin in the stack type structure laminate that a
plurality of ceramic bodies is stacked.
[0010] Herein, the ceramic bodies forming the laminate may be the
multi-layered ceramic capacitor (MLCC) that the internal electrodes
of different polarities are alternately stacked with sandwiching at
least one of the ceramic sheets, and the multi-layered ceramic
capacitor having different internal electrode structures can be
used when the laminated is formed with such multi-layered ceramic
capacitor.
[0011] The multi-layered ceramic capacitor used in the present
invention may be selected from a group consisting of a normal
structure multi-layered ceramic capacitor, an open structure
multi-layered ceramic capacitor, a thick & horizontally mounted
capacitor (T-HMC) structure multi-layered ceramic capacitors, a
float structure multi-layered ceramic capacitor, a T-HMC-open
structure multi-layered ceramic capacitor and a T-HMC-Float
structure multi-layered ceramic capacitor. Accordingly, in order to
secure high electrostatic capacitance as well as improve the
acoustic noise reduction and the crack prevention, the present
invention arranges the multi-layered ceramic capacitor selected
from one of an open structure multi-layered ceramic capacitor, a
T-HMC structure multi-layered ceramic capacitors, a float structure
multi-layered ceramic capacitor, a T-HMC-open structure
multi-layered ceramic capacitor and a T-HMC-Float structure
multi-layered ceramic capacitor at a most bottom of the laminate,
and the normal structure multi-layered ceramic capacitor is stacked
thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These and/or other aspects and advantages of the present
general inventive concept will become apparent and more readily
appreciated from the following description of the embodiments,
taken in conjunction with the accompanying drawings of which:
[0013] FIG. 1 is a cross-sectional view showing an electronic
component in accordance with one embodiment of the present
invention;
[0014] FIGS. 2A through 2F are cross-sectional views showing
multi-layered ceramic capacitors applicable to an embodiment of the
present invention;
[0015] FIG. 3 is a cross-sectional view showing an electronic
component in accordance with another embodiment of the present
invention;
[0016] FIG. 4A is a cross-sectional view showing an electronic
component in accordance with another embodiment of the present
invention;
[0017] FIG. 4B is a diagram showing an embodiment that the ceramic
body is formed with three ceramic bodies;
[0018] FIG. 5A is a cross-sectional view showing an electronic
component in accordance with another embodiment of the present
invention;
[0019] FIG. 5B is a diagram showing an embodiment that the ceramic
body is formed with three ceramic bodies;
[0020] FIG. 6 to FIG. 8 are cross-sectional views showing an
electronic component in accordance with another embodiment of the
present invention; and
[0021] FIG. 9 is a flow chart showing a method of manufacturing an
electronic component in accordance with another embodiment of the
present invention.
DETAILED DESCRIPTION
[0022] Advantages and features of the present invention and methods
of accomplishing the same will be apparent by referring to
embodiments described below in detail in connection with the
accompanying drawings. However, the present invention is not
limited to the embodiments disclosed below and may be implemented
in various different forms. The exemplary embodiments are provided
only for completing the disclosure of the present invention and for
fully representing the scope of the present invention to those
skilled in the art.
[0023] Terms used herein are provided to explain embodiments, not
limiting the present invention. Throughout this specification, the
singular form includes the plural form unless the context clearly
indicates otherwise. When terms "comprises" and/or "comprising"
used herein do not preclude existence and addition of another
component, step, operation and/or device, in addition to the
above-mentioned component, step, operation and/or device.
[0024] On the other hands, for simplicity and clarity of
illustration, the drawing figures illustrate the general manner of
construction, and descriptions and details of well-known features
and techniques may be omitted to avoid unnecessarily obscuring the
discussion of the described embodiments of the invention.
Additionally, elements in the drawing figures are not necessarily
drawn to scale. For example, the dimensions of some of the elements
in the figures may be exaggerated relative to other elements to
help improve understanding of embodiments of the present invention.
The same reference numerals in different figures denote the same
elements.
[0025] Hereinafter, the configurations and operational effects of
the present invention will be described in detail with reference to
the accompanying drawings so that those skilled in the art can
easily practice the present invention. The same reference numerals
in different figures denote the same elements.
[0026] FIG. 1 is a cross-sectional view showing an electronic
component in accordance with one embodiment of the present
invention.
[0027] Referring to FIG. 1, an electronic component 100 in
accordance with an embodiment of the present invention includes a
laminate 110 formed by stacking a plurality of ceramic bodies 110a
and 110b and a plurality of external electrodes 120 formed on
opposite ends of the laminate 110, as a stack type electronic
component having the plurality of ceramic bodies 110a and 110b
stacked in a vertical direction. According to such a structure, the
plurality of ceramic bodies 110a and 110b are connected to the pair
of external electrodes 120 in parallel.
[0028] In the embodiment of the present invention, the ceramic
bodies 110a and 110b exemplifies a multi-layered ceramic capacitor
(MLCC) in which the internal electrodes 111 with different
polarities are alternately stacked in between at least one of the
ceramic sheets inside of the body formed of a dielectric material
such as barium titanate, as a unit of the electronic component
being in charge of a predetermined function during the application
of voltage by forming the internal electrodes 111 inside of the
body made of a ceramic material. Herein, in case when the ceramic
bodies 110a and 110b are an MLCC, each MLCC is constructed to have
different electrostatic capacitances. The internal electrodes 111
of ceramic bodies 110a and 110b may include a first boundary
internal electrode and a second boundary internal electrode. All
the other internal electrodes 111 of the ceramic bodies 110a and
110b may be interposed between the first and second boundary
internal electrodes.
[0029] The ceramic bodies 110a and 110b may be stacked in between
an adhesive 130. That is, the ceramic body 110a at the bottom side
and the ceramic body 110b at the top side are bonded via the
insulating adhesive 130 such as an epoxy resin. On the other hands,
in order to improve the heat discharge characteristics, a member
having high thermal conductivity such as alumina can be used as the
material of the adhesive 130.
[0030] The pair of external electrodes 120 is formed on opposite
ends of the laminate 110, thereby assigning different polarities to
the ceramic bodies 110a and 110b. For example, the external
electrode 120 formed on a left side end of the laminate 110 is
electrically connected to the internal electrode 111 exposed to the
left side surface of the ceramic bodies 110a and 110b, thereby
assigning (+) polarity or (-) polarity, and the external electrode
120 formed on a right side end of the laminate 110 is electrically
connected to the internal electrode 111 exposed to the right side
surfaces of each of the ceramic bodies 110a and 110b, thereby
assigning the opposite polarity of the external electrode 120 at
the left side end.
[0031] Herein, the external electrode 120 is made of an
electrically conductive resin obtained by dispersing a metal powder
into a polymer resin. Although the metal powder can be any one
selected from a group consisting of Ag, Cu, Pd, Pt and an alloy
thereof, but it is not limited thereto, if it is electrically
conductive.
[0032] A thermosetting epoxy group resin may be used as a polymer
resin. Besides, if elasticity can be applied to the external
electrode 120, another resin, e.g., the thermosetting resin such as
PE, ABS, PA or the like, can be used. In case of using the
thermosetting resin, the elasticity of the external electrode 120
can be controlled by controlling the amount of a hardening
agent.
[0033] Like this, in case when the external electrodes 120 assigned
thereto have the elasticity in the stack type structure electronic
component, acoustic noise can be reduce by preventing the vibration
due to the piezoelectric effect of the dielectric material from
being transferred to a substrate (not shown). And also, the
generation of crack can be suppressed by protecting the ceramic
bodies 110a and 110b from the external impact applied during the
manufacturing process such as a sintering process or a polishing
process or when the electronic component is mounted on the
substrate.
[0034] On the other hands, a metal layer 121 may be coated on a
surface of the external electrode 120 for the convenience of
mounting. For example, the metal layer 121 may include a first
metal layer formed by including Ni as a main component formed on
the surface of the external electrode 120 and a second metal layer
formed by including Sn as a main component formed on the surface of
the first metal layer.
[0035] In order to further intensify the reduction of acoustic
noise and the crack prevention due to the external impact,
according to other embodiments, different multi-layered ceramic
capacitors having the internal electrodes with different structures
as the ceramic bodies 110a and 110b may be used to form the
laminate 110. A width of each internal electrode 111 of the ceramic
body 110a is less than that of each internal electrode 111 of the
ceramic body 110b. In a vertical direction along which the ceramic
bodies 110a and 110b stack, each internal electrode 111 of the
ceramic body 110a may overlap with extension portions of only one
of the external electrodes 120, and in the vertical direction, each
internal electrode 111 of the ceramic body 111b may overlap with
the extension portions of both of the external electrodes 120.
[0036] Herein, the structure of the internal electrode 111 is
classified into a normal structure, an open structure, a thick
& horizontally mounted capacitor structure (T-HMC), a float
structure, a T-HMC-open structure and a T-HMC-float structure
according to the formation position and size or the like of the
internal electrode 111. A capacitance of the ceramic body 110a may
be less than a capacitance of the ceramic body 110b.
[0037] FIGS. 2A through 2F are cross-sectional views showing
multi-layered ceramic capacitors applicable to an embodiment of the
present invention. Particularly, FIG. 2A shows a normal structure
multi-layered ceramic capacitor, FIG. 2B shows an open structure
multi-layered ceramic capacitor, FIG. 2C shows a T-HMC structure
multi-layered ceramic capacitor, FIG. 2D shows a float structure
multi-layered ceramic capacitor, FIG. 2E shows a T-HMC-open
structure multi-layered ceramic capacitor, and FIG. 2F shows a
T-HMC-float structure multi-layered ceramic capacitor.
[0038] Referring to FIG. 2A, the normal structure multi-layered
ceramic capacitor may be defined as a conventional structure
capacitor capable of maximizing the area of the internal electrodes
111 by positioning ends (virtual line a) of the internal electrodes
111 at an outside with reference to an end (defined by a virtual
line b) of the external electrode 120.
[0039] Referring to FIG. 2B, the open structure multi-layered
ceramic capacitor may be defined as a capacitor structure capable
of forming a margin portion M by positioning ends (virtual line a)
of the internal electrodes 111 inside with reference to an end
(virtual line b) of the external electrode 120.
[0040] And, referring to FIG. 2C, the T-HMC structure multi-layered
ceramic capacitor may be defined as a capacitor structure capable
of forming a space D between the internal electrode 111 at the
lowermost layer and the bottom surface of the body larger than that
between the internal electrode 111 at the uppermost layer and the
top surface of the body larger.
[0041] And, Referring to FIG. 2D, the float structure multi-layered
ceramic capacitor may be defined as a capacitor structure in which
floating internal electrodes 111' that are not connected to any
external electrodes 120 are arranged at the middle of the body,
wherein opposite ends (virtual line a) of the floating internal
electrodes 111' are placed inside with reference to ends (virtual
line b) of the external electrode 120s. In addition, one of the
first internal electrodes exposed to the left end of the ceramic
body and one of the internal electrodes exposed to the right end of
the ceramic body may be formed on a same plane.
[0042] And, referring to FIG. 2E, the T-HMC-open structure
multi-layered ceramic capacitor may be defined as a capacitor
formed by combining the T-HMC structure and the open structure.
Referring to FIG. 2F, the T-HMC-float structure multi-layered
ceramic capacitor may be defined as a capacitor formed by combining
the T-HMC structure and the float structure.
[0043] If the prevention of crack due to the external impact takes
priority over all else, as shown in FIG. 1, the laminate 110 can be
formed by using the open structure multi-layered ceramic capacitor.
Since the open structure multi-layered ceramic capacitor forms the
margin portion M large, as shown in FIG. 2B, although a crack may
be is generated, it does not reach to the internal electrode 111,
the laminate 110 can be protected from the external impact.
[0044] Herein, the crack generated during the process to mount the
electronic component on the substrate is transmitted to the inside
of the body by being started from the bottom surface of the body
being in contact with the substrate directly, it is proper that the
open structure multi-layered ceramic capacitor is used as the
ceramic body 110a arranged at the lowermost surface of the laminate
110.
[0045] Merely, since the electrostatic capacitance of the open
structure multi-layered ceramic capacitor becomes small in
proportional to the percentage of the area decrement, the normal
structure multi-layered ceramic capacitor can be used as the
remaining ceramic body 110b except the multi-layered ceramic
capacitor at the lowermost surface in order to secure the high
electrostatic capacitance.
[0046] As FIG. 3 is a cross-sectional view showing an electronic
component in accordance with another embodiment of the present
invention, the number of ceramic bodies 110a, 110b and 110c forming
the laminate 110 may be three or more than three.
[0047] Herein, in order to implement the maximum effect, the
ceramic body 1101 arranged at the lowermost surface is used as the
open structure multi-layered ceramic capacitor and the remaining
ceramic bodies 110b and 110c may be used as the normal structure
multi-layered ceramic capacitors. According to such configuration,
the overall of the laminate 110 can be protected by suppressing the
propagation of the crack from the bottom in the open structure
multi-layered ceramic capacitor, and the high electrostatic
capacitance can be secured through the normal structure
multi-layered ceramic capacitor. The internal electrodes 111 of
ceramic bodies 110a, 110b, and 110c may include a first boundary
internal electrode and a second boundary internal electrode. All
the other internal electrodes 111 of the ceramic bodies 110a, 110b,
and 110c may be interposed between the first and second boundary
internal electrodes. A width of each internal electrode 111 of the
ceramic body 110a may be less than that of each internal electrode
111 of the ceramic bodies 110b and 110c. In a vertical direction
along which the ceramic bodies 110a, 110b, and 110c stack, each
internal electrode 111 of the ceramic body 110a may overlap with
extension portions of only one of the external electrodes 120, and
in the vertical direction, each internal electrode 111 of the
ceramic bodies 111b and 110c may overlap with the extension
portions of both of the external electrodes 120. A capacitance of
the ceramic body 110a may be less than a capacitance of each of the
remaining ceramib bodies 110b and 110c.
[0048] FIG. 4A is a cross-sectional view showing an electronic
component including two multi-layered ceramic capacitors in
accordance with another embodiment of the present invention, and
FIG. 4B is a diagram showing an embodiment that the ceramic body is
formed of three multi-layered ceramic capacitors.
[0049] If the reduction of acoustic noises takes priority over all
else, as shown in FIG. 4A, the laminate 110 can be formed by using
the T-HMC structure multi-layered ceramic capacitor. The internal
electrodes 111 of ceramic bodies 110a and 110b may include a first
boundary internal electrode and a second boundary internal
electrode. All the other internal electrodes 111 of the ceramic
bodies 110a and 110b may be interposed between the first and second
boundary internal electrodes. A distance D between the first
boundary internal electrode and a bottom exterior surface of the
laminate 110 connected between the ends of the laminate 110 may be
larger than a distance between the second boundary internal
electrode and a top exterior surface of the laminate 110 connected
between the ends of the laminate 110, and may be larger than any
distances of the one or more adhesive layers 130 to the internal
electrodes 111 which are immediately adjacent to the respective one
or more adhesive layers 130. The distance between the second
boundary internal electrode and the top surface of the laminate 110
connected between the ends of the laminate 110, and each distance
between the one or more adhesive layers 130 and the internal
electrodes 111 which are immediately adjacent to the respective one
or more adhesive layers 130, may be substantially equal to each
other. In a vertical direction along which the ceramic bodies 110a
and 110b stack, each internal electrode 111 may overlap with
extension portions of both of the first and second external
electrodes 120. A capacitance of the ceramic body 110a may be less
than a capacitance of the ceramib body 110b. Since the T-HMC
structure multi-layered ceramic capacitor forms the space D between
the inner electrode 111 at the lowermost layer of the inner
electrode 111 and the bottom surface of the body large, as shown in
FIG. 2C, the vibration V due to the piezoelectric effect cannot
reach to the substrate to thereby reduce the acoustic noises.
[0050] But, since the number of stacking the inner electrodes 111
is necessarily reduced by the amount of widening the space D
between the inner electrode 111 at the lowermost layer of the inner
electrode 111 and the bottom surface of the body, the T-HMC
structure multi-layered ceramic capacitor is used as the ceramic
body 110a arranged at the lowermost surface of the laminate 110, in
order to secure the high electrostatic capacitance, the normal
structure multi-layered ceramic capacitor can be used as the
remaining ceramic body 110b except the multi-layered ceramic
capacitor at the lowermost surface. At this time, as shown in FIG.
4B, two or more normal structure multi-layered ceramic capacitors
may be stacked on top of the T-HMC structure multi-layered ceramic
capacitor. In this case, the internal electrodes 111 of ceramic
bodies 110a, 110b, and 110c may include a first boundary internal
electrode and a second boundary internal electrode. All the other
internal electrodes 111 of the ceramic bodies 110a, 110b, and 110c
may be interposed between the first and second boundary internal
electrodes. A distance D between the first boundary internal
electrode and a bottom exterior surface of the laminate 110
connected between the ends of the laminate 110 may be larger than a
distance between the second boundary internal electrode and a top
exterior surface of the laminate 110 connected between the ends of
the laminate 110, and may be larger than any distances of the one
or more adhesive layers 130 to the internal electrodes 111 which
are immediately adjacent to the respective one or more adhesive
layers 130. The distance between the second boundary internal
electrode and the top surface of the laminate 110 connected between
the ends of the laminate 110, and each distance between the one or
more adhesive layers 130 and the internal electrodes 111 which are
immediately adjacent to the respective one or more adhesive layers
130, may be substantially equal to each other. In a vertical
direction along which the ceramic bodies 110a, 110b, and 110c
stack, each internal electrode 111 may overlap with extension
portions of both of the first and second external electrodes 120. A
capacitance of the ceramic body 110a may be less than a capacitance
of each of the remaining ceramic bodies 110b and 110c.
[0051] FIG. 5A is a cross-sectional view showing an electronic
component in accordance with another embodiment of the present
invention and FIG. 5B is a diagram showing an embodiment that the
ceramic body is formed with three ceramic bodies.
[0052] If the prevention of shorts between the inner electrodes 111
and the external electrodes 120 takes priority over all else, as
shown in FIG. 5A, the laminate 110 can be formed by using the float
structure multi-layered ceramic capacitor. Since the float
structure multi-layered ceramic capacitor is an open structure that
the inner electrodes 111 provided in the middle of the body are
separated from both sides of the external electrodes 120 by a
predetermined space, although the crack due to the external impact
or the ceramic contraction during the sintering process is
generated, the shorts with the external electrodes 120 can be
prevented.
[0053] And, even when the float structure capacitor is used, by
using the norm structure multi-layered ceramic capacitors as the
remaining except the float structure capacitor, the high
electrostatic capacitance can be secured, at this time; and, the
normal structure multi-layered ceramic capacitor may be formed of
at least two, as shown in FIG. 5B.
[0054] FIG. 6 to FIG. 8 are cross-sectional views showing an
electronic component in accordance with another embodiment of the
present invention. The same reference numerals will be used to
refer to the same or like parts as those described in precious
embodiment, and any further explanation will be omitted.
[0055] The present invention can arrange the T-HMC-open structure
multi-layered ceramic capacitor at the lowermost surface of the
laminate 110, as the embodiment of FIG. 6, in order to achieve the
prevention of crack and short due to the external impacts and the
reduction of acoustic noise at the same time or can arrange the
T-HMC-float structure multi-layered ceramic capacitor at the
lowermost surface of the laminate 110, as the embodiment of FIG.
7.
[0056] Or, as the embodiment of FIG. 8, the ceramic bodies 110a,
110b and 110c are formed of three, and the open structure
multi-layered ceramic capacitor, the T-HMC structure multi-layered
ceramic capacitor and the normal structure multi-layered ceramic
capacitor can be stacked in order from the lowermost surface of the
laminate 110. That is, in the open structure multi-layered ceramic
capacitor arranged at the lowermost surface, the crack transmitted
inside of the body is suppressed, in the T-HMC-open structure
multi-layered ceramic capacitor arranged in the middle, the
vibration due to the piezoelectric effect is prevented from being
transmitted to the substrate and the high electrostatic capacitance
can be secured through the normal structure multi-layered ceramic
capacitor arranged at the uppermost surface.
[0057] Although, in the embodiment of FIG. 8, there is explained
that two ceramic bodies 110a and 110b stacked from the lowermost
surface of the laminate are the open structure multi-layered
ceramic capacitor and the T-HMC structure multi-layered ceramic
capacitor as an example, but it is not limited thereto, the ceramic
bodies 110a and 110b may be variously formed by combining the open
structure, the T-HMC structure, the float structure, the T-HMC-open
structure, the T-HMC-float structure or the like.
[0058] Hereinafter, the method of manufacturing the electronic
component of the present invention will be explained.
[0059] As FIG. 9 is a flow chart showing a method of manufacturing
an electronic component in accordance with another embodiment of
the present invention, a plurality of different multi-layered
ceramic capacitors are prepared (S100) as a first step to
manufacture the electronic component of the present invention.
Particularly, the multi-layered ceramic capacitor may be selected
from a group consisting of a normal structure multi-layered ceramic
capacitor, an open structure multi-layered ceramic capacitor, a
thick & horizontally mounted capacitor (T-HMC) structure
multi-layered ceramic capacitors, a float structure multi-layered
ceramic capacitor, a T-HMC-open structure multi-layered ceramic
capacitor and a T-HMC-Float structure multi-layered ceramic
capacitor.
[0060] Thereafter, a step of stacking the prepared plurality of
multi-layered ceramic capacitors is performed (S110). At this time,
after the adhesive resin is coated between the multi-layered
ceramic capacitor at the top side and the multi-layered ceramic
capacitor at the bottom side to be cured, the multi-layered ceramic
capacitors at the top and bottom sides can be stably fixed.
[0061] In the present step, the products capable of securing the
high electrostatic capacitance as well as preventing the crack due
the external impact and the acoustic noises due to the
piezoelectric effect by arranging the multi-layered ceramic
capacitor selected from one of an open structure, a T-HMC
structure, a float structure, a T-HMC-open structure and a
T-HMC-Float structure at a lowermost bottom of the laminate and
stacking the normal structure multi-layered ceramic capacitor
thereon. At this time, the normal structure multi-layered ceramic
capacitors can be stacked at least two.
[0062] Or, when three multi-layered ceramic capacitors are stacked,
the electronic component in accordance with the present invention
can be manufactured by arranging the multi-layered ceramic
capacitor selected from one of an open structure, a T-HMC
structure, a float structure, a T-HMC-open structure and a
T-HMC-Float structure at a lowermost bottom, stacking thereon the
multi-layered ceramic capacitor different from the multi-layered
ceramic capacitor arranged at the lowermost bottom among one of an
open structure, a T-HMC structure, a float structure, a T-HMC-open
structure and a T-HMC-Float structure and stacking the normal
structure multi-layered ceramic capacitor at the uppermost top
surface.
[0063] Finally, the electronic component of the present invention
is finished (S120) by forming the external electrode 120 made of a
conductive resin on opposite ends of the laminate 110 stacked
thereon the plurality of multi-layered ceramic capacitors.
[0064] The external electrode 120 may be formed by coating a
conductive paste on opposite ends of the laminate 110 and sintering
the coated conductive paste. Herein, the method for coating the
conductive paste is not limited to a specific method, for example,
various methods such as a dipping, a painting, a printing or the
like can be used.
[0065] The conductive paste may be manufactured by adding the metal
powder, e.g., at the state that the epoxy resin and the hardening
agent are solved by the solvent. Accordingly, the solvent is
removed in the drying process and the epoxy resin is cured by the
following heat treatment thereby forming the external electrode 120
having the elasticity.
[0066] In accordance with the present invention, since the
mechanical vibration and the external impact are absorbed through
the external electrode having the elasticity, the generation of
crack transmitted inside of the ceramic body is suppressed and the
piezoelectric vibration transmitted to the substrate is blocked to
thereby reduce the acoustic noise.
[0067] And also, according to constructing the laminate with the
plurality of different multi-layered ceramic capacitors, the high
electrostatic capacitance can be secured by reducing the acoustic
noise and preventing the crack and the short failure due to the
external impact.
[0068] The foregoing description illustrates the present invention.
Additionally, the foregoing description shows and explains only the
preferred embodiments of the present invention, but it is to be
understood that the present invention is capable of use in various
other combinations, modifications, and environments and is capable
of changes and modifications within the scope of the inventive
concept as expressed herein, commensurate with the above teachings
and/or the skill or knowledge of the related art. The embodiments
described hereinabove are further intended to explain best modes
known of practicing the invention and to enable others skilled in
the art to utilize the invention in such, or other, embodiments and
with the various modifications required by the particular
applications or uses of the invention. Accordingly, the description
is not intended to limit the invention to the form disclosed
herein. Also, it is intended that the appended claims be construed
to include alternative embodiments.
* * * * *