Patent Publication Number: US-2023141373-A1

Title: Composite electronic component

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     The present application claims the benefit of priority to Korean Patent Application No. 10-2021-0154817, filed on Nov. 11, 2021 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a composite component, for example, a composite electronic component in which a ceramic electronic component and an interposer are vertically coupled to each other. 
     BACKGROUND 
     With the recent trend for higher capacitance of electronic devices such as smartphones, chargers, and laptop computers, more multilayer ceramic capacitors (MLCCs) are being applied. However, acoustic noise generated by the MLCC may cause discomfort to users. Therefore, MLCCs for suppressing generation of acoustic noise are being actively developed. 
     For example, research into a composite electronic component, in which an interposer is coupled to a lower portion of an MLCC, has been conducted. In a composite electronic component, an interposer attached to a lower portion of an MLCC may reduce transmission of vibrations of the MLCC, caused by a piezoelectric effect, to a main printed circuit board (PCB) during an operation of the MLCC to reduce acoustic noise. 
     However, such a composite electronic component may generate a difference in coefficients of thermal expansion (CTE) between an MLCC and an interposer, which may increase thermal stress inside the MLCC during a reflow process. Cracking may occur in the MLCC due to such thermal stress, resulting in poor reliability such as a burnt defect. 
     SUMMARY 
     An aspect of the present disclosure is to provide a composite electronic component which may reduce thermal stress generated inside a ceramic electronic component. 
     Exemplary embodiments in the present disclosure provide various solutions, and one of the solutions is to introduce an electrode layer having a relatively low modulus into an external electrode of a ceramic electronic component. 
     According to an aspect of the present disclosure, a composite electronic component includes a ceramic electronic component including a body, comprising a dielectric layer and an internal electrode, and an external electrode disposed on the body and connected to the internal electrode; and an interposer including a substrate, disposed below the body, and a connection electrode disposed on the substrate and connected to the external electrode by a connection member. The external electrode includes a first electrode layer including metal particles and an insulating resin. 
     According to an aspect of the present disclosure, a composite electronic component includes: a ceramic electronic component including a body, comprising a dielectric layer and an internal electrode, and an external electrode disposed on the body and connected to the internal electrode; and an interposer including a substrate, disposed below the body, and a connection electrode disposed on the substrate and connected to the external electrode by a connection member. The external electrode includes a first electrode layer, disposed on the body, and a second electrode layer disposed on the first electrode layer. The first electrode layer has a modulus lower than a modulus of the second electrode layer. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       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. 
         FIG.  1    is a schematic perspective view of a composite electronic component according to an exemplary embodiment in the present disclosure. 
         FIG.  2    is a schematic cross-sectional view, illustrating an example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
         FIG.  3    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
         FIG.  4    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
         FIG.  5    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
         FIG.  6    is a schematic cross-sectional view illustrating a mechanism in which thermal stress is generated inside a single piece of ceramic electronic component during a reflow process. 
         FIG.  7    is a schematic cross-sectional view illustrating a mechanism in which thermal stress is generated inside a composite electronic component. 
         FIG.  8    is a simulation result illustrating maximum stress generated inside a chip during reflow of various types of composite electronic component, as compared with a single piece of ceramic electronic component. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments in the present disclosure will be described with reference to the accompanying drawings. In the accompanying drawings, shapes, sizes, and the like, of components may be exaggerated or shortened for clarity. 
       FIG.  1    is a schematic perspective view of a composite electronic component according to an exemplary embodiment in the present disclosure. 
     Referring to  FIG.  1   , a composite electronic component  500  according to an exemplary embodiment may include a ceramic electronic component  100  and an interposer  200 . The ceramic electronic component  100  and the interposer  200  may be vertically laminated to be coupled to each other. The ceramic electronic component  100  and the interposer  200  may be coupled to each other through connection members  331  and  332  including a solder, a conductive adhesive, and the like. For example, external electrodes  131  and  132  to be described later of the ceramic electronic component  100  and connection electrodes  231  and  232  to be described later of the interposer  200  may be connected to each other using a solder, a conductive adhesive, or the like. As a non-limiting example, after applying a solder to the connection electrodes  231  and  232  of the interposer  200 , the ceramic electronic component  100  may be laminated on the interposer  200  to connect the external electrodes  131  and  132  to the connection electrodes  231  and  232 . When a temperature is increased to a high temperature, at which a solder melts through a reflow process, and is then decreased, the solder may be hardened and bonding may be completed. In some embodiments, the connection member may cover an edge of the connection electrode. In some embodiments, the connection member may contact a first surface of the connection electrode facing the ceramic electronic component, and a second surface of the connection electrode adjacent to the first surface of the connection electrode. 
     The ceramic electronic component  100  may include a body  110 , including a dielectric layer  111  and internal electrodes  121  and  122 , and external electrode  131  and  132  disposed on the body  110  and connected to the internal electrodes  121  and  122 . The body  110  may have a substantially hexahedral shape having a first surface (or a left surface) and a second surface (or a right surface) opposing each other in an X direction (or a length direction), a third surface (or a front surface) and a fourth surface (or a rear surface) opposing each other in a Y direction (or a width direction)), and a fifth surface (or an upper surface) and a sixth surface (a lower surface) opposing each other in a Z direction (or a thickness direction). As necessary, an angular exterior of the body  110 , for example, a corner portion of the body  110 , may be polished to be rounded by a polishing process, or the like. As necessary, the external electrodes  131  and  132  may have an angular shape, for example, a rounded shape, and may have a concave shape and/or a convex shape in some regions. 
     The dielectric layer  111  may be formed by sintering a ceramic green sheet including ceramic powder particles, an organic solvent, and an organic binder. The ceramic powder particles are a material having a high-k dielectric constant. As the ceramic powder particles, a barium titanate (BaTiO 3 )-based material, a strontium titanate (SrTiO 3 )-based material, or the like. As described above, the dielectric layer  111  may include a ferroelectric material, but exemplary embodiments are not limited thereto. The dielectric layer  111  may be in a state, in which a plurality of layers are laminated and sintered, and may be integrated with each other such that boundaries between adjacent layers are not readily apparent to the naked eye. 
     The internal electrodes  121  and  122  may be formed by a conductive paste including a conductive metal. For example, the internal electrodes  121  and  122  may be printed by printing a conductive paste on the ceramic green sheet, forming the dielectric layer  111 , through a printing method such as a screen-printing method or a gravure printing method. When the ceramic green sheets, on which the internal electrodes  121  and  122  are printed, are alternately laminated and sintered, the body  110  may be formed. The conductive metal may include, but is not limited to, nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and/or alloys thereof. 
     The internal electrodes  121  and  122  may include a plurality of first internal electrodes  121  and a plurality of second internal electrodes  122 . The plurality of first and second internal electrodes  121  and  122  may be disposed to be separated from each other with respective dielectric layers  111  interposed therebetween. The plurality of first and second internal electrodes  121  and  122  may be alternately laminated in the Y direction of the body  110  and may be exposed to the first and second surfaces of the body  110 , respectively. As a result, the plurality of first and second internal electrodes  121  and  122  may be connected to first and second external electrodes  131  and  132  to be described later, respectively. However, this is only an example, and the plurality of first and second internal electrodes  121  and  122  may be arranged in other forms. For example, the plurality of first and second internal electrodes  121  and  122  may be alternately laminated in the Z direction of the body  110  to be respectively exposed to the first and second surfaces of the body  110 , but exemplary embodiments are not limited thereto. 
     The external electrodes  131  and  132  may include a first external electrode  131  and a second external electrode  132 . The first and second external electrodes  131  and  132  may be disposed on opposite end portions of the body  110  in the X direction, respectively. For example, the first external electrode  131  may be disposed on the first surface of the body  110  to extend partially upwardly of the third to sixth surfaces of the body  110 , and the second external electrode  132  may be disposed on the second surface of the body  110  to extend partially upwardly of the third to sixth surfaces of the body  110 . However, this is only an example, and the first and second external electrodes  131  and  132  may be disposed in other forms. For example, the first external electrode  131  may be disposed on the first surface of the body  110  to extend partially upwardly of the fifth and sixth surfaces of the body  110 , and the second external electrode  132  may be disposed on the second surface of the body  110  to extend partially upwardly of the fifth and sixth surfaces of the body  110 . However, example embodiments are not limited thereto, and this is also only another example. 
     The external electrodes  131  and  132  may include one or more electrode layers, as will be described later. The one or more electrode layers of the external electrodes  131  and  132  may include a first electrode layer, a second electrode layer, and/or a third electrode layer, which will be described later. 
     The interposer  200  includes a substrate  210  and connection electrodes  231  and  232  disposed on the substrate  210 . The substrate  210  may have a substantially hexahedral shape having a first surface (or a left surface) and a second surface (or a right surface) opposing each other in the X direction (or the length direction), a third surface (or a front surface) and a fourth surface (a rear surface) opposing each other in the Y direction (or the width direction), and a fifth surface (or an upper surface) and a sixth surface (or a lower surface) opposing each other in the Z direction (or the thickness direction). As necessary, an angular exterior of the substrate  210 , for example, a corner portion of the substrate  210 , may be polished to be rounded. As necessary, an angular exterior of the connection electrodes  231  and  232 , for example, a corner portion of the connection electrodes  231  and  232 , may also have a rounded shape, and may have a concave shape and/or a convex shape in some regions. 
     The substrate  210  may include various types of material. For example, the substrate  210  may be an insulating substrate including various types of thermosetting resin and/or thermoplastic resins. Alternatively, the substrate  210  may be a ceramic substrate including alumina (Al 2 O 3 ). When the substrate  210  is a ceramic substrate, transmission of vibration generated from the ceramic electronic component  100  may be more effectively blocked because a material of the ceramic substrate is relatively hard. As a result, acoustic noise may be more effectively reduced. 
     The connection electrodes  231  and  232  may include a first connection electrode  231  and a second connection electrode  232 . The first and second connection electrodes  231  and  232  may be disposed in opposite end portions of the substrate  210  in the X direction, respectively. For example, the first connection electrode  231  may be disposed on the first surface of the substrate  210  to extend partially upwardly of the third surface to the sixth surface, and the second connection electrode  232  may be disposed on the second surface of the substrate  210  to partially extended upwardly of the third to sixth surfaces. However, this is only an example, and the first and second connection electrodes  231  and  232  may be disposed in another form. For example, the first connection electrode  231  may be disposed on the first surface of the substrate  210  to extend partially upwardly of the fifth and sixth surfaces, and the second connection electrode  232  may be disposed on the second surface of the substrate  210  to extend partially upwardly of the fifth and sixth surfaces. However, exemplary embodiments are not limited thereto, and this is also only another example. 
     The connection electrodes  231  and  232  may include one or more electrode layers, as will be described later. The one or more electrode layers of the connection electrodes  231  and  232  may include a conductive resin layer and/or a plating layer, which will be described in detail later. 
     The ceramic electronic component  100  may be relatively larger than the interposer  200 . For example, the body  110  of the ceramic electronic component  100  may be higher in length, thickness, and width than the interposer  200 . The lengths, thicknesses, and widths of the ceramic electronic component  100  and the interposer  200  may be determined by, for example, a scanning electron microscope. In this case, the ceramic electronic component  100  may have better space efficiency than in the case in which the composite electronic component  500  is mounted on the main substrate. However, this is only an example. As necessary, the substrate  210  of the interposer  200  may be higher in length and width than the body  110  of the ceramic electronic component  100 . 
       FIG.  2    is a schematic cross-sectional view, illustrating an example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
     Referring to  FIG.  2   , a composite electronic component  500 A according to an exemplary embodiment may include a ceramic electronic component  100  in which external electrodes  131  and  132  are disposed on a body  110 , and first electrode layers  131   a  and  132   a  are connected to external electrodes  121  and  122 . For example, the first external electrode  131  may include a 1-1-th electrode layer  131   a  as an electrode layer, and the second external electrode  132  may include a 1-2-th electrode layer  132   a  as an electrode layer. The 1-1-th electrode layer  131   a  may be connected to a plurality of first internal electrodes  121 . The 1-2-th electrode layer  132   a  may be connected to a plurality of second internal electrodes  122 . 
     The 1-1-th electrode layer  131   a  may be disposed on a first surface of the body  110  to extend partially upwardly of third to sixth surfaces of the body  110  or only fifth and sixth surfaces of the body  110 , but exemplary embodiments are not limited thereto. The 1-2-th electrode layer  132   a  may be disposed on a second surface of the body  110  to extend partially upwardly of the third to sixth surfaces of the body  110 , or only the fifth and sixth surfaces of the body  110 , but exemplary embodiments are not limited thereto. 
     Each of the first electrode layers  131   a  and  132   a  may be directly disposed on at least one surface of the body  110 . For example, the 1-1-th electrode layer  131   a  may be directly disposed on the first surface of the body  110 , and a portion of the 1-1-th electrode layer  131   a  may be disposed to directly extend to the third to sixth surfaces of the body  110  or to directly extend to only the fifth and sixth surfaces. In addition, the 1-2-th electrode layer  132   a  may be directly disposed on the second surface of the body  110 , and a portion of the 1-2-th electrode layer  132   a  may be disposed to directly extend to the third to sixth surfaces of the body  110  or to directly extend to only the surface and the sixth surface. 
     Here, “a certain electrode layer is directly disposed on one surface of a body” may mean that another electrode layer is not present between the certain electrode layer and the one surface of the body. For example, even when end portions of the first electrode layers  131   a  and  132   a  are in direct contact with portions of the fifth and sixth surfaces of the body  110  as illustrated in  FIG.  4    to be described later, third electrode layers  131   c  and  132   c  may be present between the first electrode layers  131   a  and  132   a  and the fifth and sixth surfaces of the body  110 . In this case, the first electrode layers  131   a  and  132   a  may not be considered to be directly disposed on the fifth and sixth surfaces of the body  110 . 
     The first electrode layers  131   a  and  132   a  may have a modulus lower than that of a conductive layer or a metal layer including copper (Cu), nickel (Ni), tin (Sn), or the like. For example, first electrode layers  131   a  and  132   a  may be relatively more flexible than the conductive layer or the metal layer. The term “flexible” may refer to a modulus relatively lower than that of a metal itself. For example, the first electrode layers  131   a  and  132   a  may have a modulus lower than that of a conductive layer or a metal layer such as a copper (Cu) layer, a nickel (Ni) layer, or a tin (Sn) layer. In this regard, the first electrode layers  131   a  and  132   a  may have a modulus of 10 GPa or less, for example, about 5 GPa to 7 GPa or about 3 GPa to 5 GPa. The modulus may be an elastic modulus. The elastic modulus may refer to a ratio of stress to strain, and may be measured through, for example, a standard tensile test specified in JIS C-6481, KS M 3001, KS M 527-3, ASTM D882, and the like, but example embodiments are not limited thereto. 
     The first electrode layers  131   a  and  132   a  may include metal particles and an insulating resin. The first electrode layers  131   a  and  132   a  may include such a mixture material to have a modulus lower than that of a layer including only a metal. The metal particles may include copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), nickel (Ni), lead (Pb), titanium (Ti), and/or alloys thereof, in detail, copper (Cu), silver (Ag), and/or alloys thereof, but exemplary embodiments are not limited thereto. The insulating resin may include a thermosetting resin such as epoxy and/or a thermoplastic resin such as polyimide, in detail, epoxy, but exemplary embodiments are not limited thereto. As a non-limiting example, the first electrode layers  131   a  and  132   a  may include a copper (Cu)-epoxy mixture material or a silver (Ag)-epoxy mixture material. The first electrode layers  131   a  and  132   a  may be formed by applying a mixture material, including metal particles and an insulating resin, and curing the applied mixture material, but exemplary embodiments are not limited thereto. 
     As in one example, when the external electrodes  131  and  132  of the ceramic electronic component  100  include the first electrode layers  131   a  and  132   a , the interposer  200  may relatively expand during reflow temperature reduction as compared with the ceramic electronic component  100 . In this case, a difference in coefficient of thermal expansion (CTE) between the ceramic electronic component  100  and the interposer  200  may be effectively eliminated as the first electrode layers  131   a  and  132   a  are stretched. Accordingly, the thermal stress generated inside the ceramic electronic component  100  may be more effectively reduced. This will be described in detail later. 
     Continuing to refer to  FIG.  2   , the composite electronic component  500 A according to an exemplary embodiment may include conductive resin layers  231   a  and  232   a , in which the connection electrodes  231  and  232  of the interposer  200  are disposed on a substrate  210 , and plating layers  231   b  and  232   b  disposed on the conductive resin layers  231   a  and  232   a . For example, the first connection electrode  231  may include a first conductive resin layer  231   a  and a first plating layer  231   b , and the second connection electrode  232  may include a second conductive resin layer  232   b  and a second conductive resin layer  231   b.    
     The first conductive resin layer  231   a  may be disposed on the first surface of the substrate  210  to extend partially upwardly of the third to sixth surfaces of the substrate  210 , or to extend partially upwardly of the fifth and sixth surfaces of the substrate  210 , and the first plating layer  231   b  may be disposed on the first conductive resin layer  231   a  to cover the first conductive resin layer  231   a , but exemplary embodiments are not limited thereto. The second conductive resin layer  232   a  may be disposed on the second surface of the substrate  210  to extend partially upwardly of the third to sixth surfaces of the substrate  210  or to extend partially upwardly of the fifth and sixth surfaces of the substrate  210 , and the second plating layer  232   b  may be disposed on the second conductive resin layer  232   a  to cover the second conductive resin layer  232   a , but exemplary embodiments are not limited thereto. 
     The conductive resin layers  231   a  and  232   a  may protect the composite electronic component  500  from mechanical and/or thermal stress and warpage impact of the substrate, resulting from a process temperature when the composite electronic component  500  is mounted on a main substrate, or the like. The conductive resin layers  231   a  and  232   a  may include conductive particles and a dispersion resin. The conductive particles may include copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), nickel (Ni), lead (Pb), titanium (Ti), and/or alloys thereof, in detail, copper (Cu), nickel (Ni), and/or alloys thereof. However, exemplary embodiments are not limited thereto, and the conductive resin layers  231   a  and  232   a  may include conductive particles other than a metal such as carbon particles. The dispersion resin may include a thermosetting resin such as epoxy, acryl, melamine, phenol, polyimide, resol-type phenol, and unsaturated polyester, in detail, epoxy. However, exemplary embodiments are not limited thereto, and the dispersion resin may include a photocurable resin. The conductive resin layers  231   a  and  232   b  may be formed by applying a mixture material, including conductive particles and a dispersion resin, and curing the applied mixture material, but exemplary embodiments are not limited thereto. 
     The plating layers  231   b  and  232   b  may improve connection reliability of the connection electrodes  231  and  232 . The plating layers  231   b  and  232   b  may include a nickel (Ni) plating layer, a tin (Sn) plating layer, or a combination thereof. For example, the first plating layer  231   b  may include a first nickel (Ni) plating layer, covering the first conductive resin layer  231   a , and a first tin (Sn) plating layer covering the first nickel (Ni) plating layer. The second plating layer  232   b  may include a second nickel (Ni) plating layer, covering the second conductive resin layer  232   a , and a second tin (Sn) plating layer covering the second nickel (Ni) plating layer. However, exemplary embodiments are not limited thereto, and other plating materials may be used. The plating layers  231   b  and  232   b  may be formed by a known plating process such as an electrolytic plating process, an electroless plating process, or the like, and a detailed plating method is not limited. 
       FIG.  3    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
     Referring to  FIG.  3   , a composite electronic component  500 B according to another exemplary embodiment may include a ceramic electronic component  100  in which external electrodes  131  and  132  are disposed on a body  110 , first electrodes  131   a  and  132   a  are connected to internal electrodes  121  and  122 , and second electrodes  131   b  and  132   b  are disposed on the first electrode layer  131   a  and  132   a . For example, the first external electrode  131  may include a 1-1-th electrode layer  131   a  and a 2-1-th electrode layer  131   b  as a plurality of electrode layers. The second external electrode  132  may include a 1-2-th electrode layer  132   a  and a 2-2-th electrode layer  132   b  as a plurality of electrode layers. The 1-1-th electrode layer  131   a  may be connected to the plurality of first internal electrodes  121 . The 1-2-th electrode layer  132   a  may be connected to the plurality of second internal electrodes  122 . The first electrode layers  131   a  and  132   a  may be thicker than the second electrode layers  131   b  and  132   b , but exemplary embodiments are not limited thereto. 
     The 1-1-th electrode layer  131   a  may be disposed on a first surface of the body  110  to extend partially upwardly of third to sixth surfaces of the body  110  or to extend partially upwardly of only fifth and sixth surfaces of the body  110 , and the 2-1-th electrode layer  131   b  may be disposed on the 1-1 electrode layer  131   a  to cover the 1-1 electrode layer  131   a , but exemplary embodiments are not limited thereto. The 1-2-th electrode layer  132   a  may be disposed on the second surface of the body  110  to extend partially upwardly of the third to sixth surfaces of the body  110  or to extend partially upwardly of the fifth and sixth surfaces of the body  110 , and the 2-2-th electrode layer  132   b  may be disposed on the 1-2-th electrode layer  132   a  to cover the 1-2-th electrode layer  132   a , but exemplary embodiments are not limited thereto. 
     Each of the first electrode layers  131   a  and  132   a  may be directly disposed on at least one surface of the body  110 . For example, the 1-1-th electrode layer  131   a  may be directly disposed on the first surface of the body  110 , and a portion of the 1-1-th electrode layer  131   a  may be disposed to directly extend to the third to sixth surfaces of the body  110  or to directly extend to only the fifth and sixth surfaces. The 2-1-th electrode layer  131   b  may be directly disposed on the 1-1-th electrode layer  131   a . In addition, the 1-2-th electrode layer  132   a  may be directly disposed on the second surface of the body  110 , and a portion of the 1-2-th electrode layer  132   a  may be disposed to directly extend to the third to sixth surfaces of the body  110  or to directly extend to only the fifth and the sixth surfaces. The 2-2-th electrode layer  132   b  may be directly disposed on the 1-2-th electrode layer  132   a.    
     Here, “one electrode layer is directly disposed on another electrode layer” may mean that an additional electrode layer is not present between the electrode layers. 
     The second electrode layers  131   b  and  132   b  may improve connection reliability of the external electrodes  131  and  132 . The second electrode layers  131   b  and  132   b  may include a metal layer including nickel (Ni), a metal layer including tin (Sn), or a combination thereof. For example, the 2-1-th electrode layer  131   b  may include a first nickel (Ni) layer, covering the 1-1-th electrode layer  131   a , and a first tin (Sn) layer covering the first nickel (Ni) layer. The 2-2-th electrode layer  132   b  may include a second nickel (Ni) layer, covering the 1-2 electrode layer  132   a , and a second tin (Sn) layer covering the second nickel (Ni) layer. However, exemplary embodiments are not limited thereto, and the second electrode layers  131   b  and  132   b  may include another metal. The second electrode layers  131   b  and  132   b  may be formed by a known plating process such as an electrolytic plating process or an electroless plating process, and a detailed plating method is not limited. 
     The other contents are substantially the same as described in the above-described composite electronic component  500 A according to an exemplary embodiment, and redundant descriptions will be omitted. 
       FIG.  4    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
     Referring to  FIG.  4   , a composite electronic component  500 C according to another exemplary embodiment may include a ceramic electronic component  100  in which external electrodes  131  and  132  are disposed on a body  110 , third electrode layers  131   c  and  132   c  are connected to internal electrodes  121  and  122 , first electrode layers  131   a  and  132   a  are disposed on the third electrode layers  131   c  and  132   c , and second electrode layers  131   b  and  132   b  disposed on the first electrode layers  131   a  and  132   a . For example, the first external electrode  131  may include a 3-1-th electrode layer  131   c , a 1-1-th electrode layer  131   a , and a 2-1-th electrode layer  131   b  as a plurality of electrode layers. The second external electrode  132  may include a 3-2-th electrode layer  132   c , a 1-2-th electrode layer  132   a , and a 2-2-th electrode layer  132   b  as a plurality of electrode layers. The 3-1-th electrode layer  131   c  may be connected to the plurality of first internal electrodes  121 . The 3-2-th electrode layer  132   c  may be connected to the plurality of second internal electrodes  122 . The third electrode layers  131   c  and  132   c  may be thicker than the first electrode layers  131   a  and  132   a , and the first electrode layers  131   a  and  132   a  may be thicker than the second electrode layers  131   b  and  132   b , but exemplary embodiments are not limited thereto. 
     The 3-1-th electrode layer  131   c  may be disposed on a first surface of the body  110  to extend partially upwardly of third to sixth surfaces of the body  110  or to extend partially upwardly of only fifth and sixth surfaces of the body  110 , the 1-1-th electrode layer  131   a  may be disposed on the 3-1-th electrode layer  131   c  to cover the 3-1-th electrode layer  131   c , and the 2-1-th electrode layer  131   b  may be disposed on the 1-1-th electrode layer  131   a  to cover the 1-1-th electrode layer  131   a , but exemplary embodiments are not limited thereto. The 3-2-th electrode layer  132   c  may be disposed on the second surface of the body  110  to extend partially upwardly of the third to sixth surfaces of the body  110  or to extend upwardly of only the fifth and sixth surfaces of the body  110 , the 1-2-th electrode layer  132   a  may be disposed on the 3-2-th electrode layer  132   c  to cover the 3-2-th electrode layer  132   c , and the 2-2-th electrode layer  132   b  may be disposed on the 1-2-th electrode layer  132   a  to cover the 1-2-th electrode layer  132   a , but exemplary embodiments are not limited thereto. 
     Each of the third electrode layers  131   c  and  132   c  may be directly disposed on at least one surface of the body  110 . For example, the 3-1-th electrode layer  131   c  may be directly disposed on a first surface of the body  110 , and a portion of the 3-1-th electrode layer  131   c  may be disposed to directly extend to third to sixth surfaces of the body  110  or to directly extend to only fifth and sixth surfaces of the body  100 . The 1-1-th electrode layer  131   a  may be directly disposed on the 3-1-th electrode layer  131   c . The 2-1-th electrode layer  131   b  may be directly disposed on the 1-1-th electrode layer  131   a . In addition, the 3-2-th electrode layer  132   c  may be directly disposed on the second surface of the body  110 , and a portion of the 3-2-th electrode layer  132   c  may be disposed to directly extend to the third to sixth surfaces of the body  110  or to directly extend to only the fifth and sixth surfaces of the body  110 . The 1-2-th electrode layer  132   a  may be directly disposed on the 3-2-th electrode layer  132   c . The 2-2-th electrode layer  132   b  may be directly disposed on the 1-2-th electrode layer  132   a.    
     Improved connectivity between the internal electrodes  121  and  122  and the external electrodes  131  and  132  may be secured through the third electrode layers  131   c  and  132   c . The third electrode layers  131   c  and  132   c  may include a conductive material. For example, each of the third electrode layers  131   c  and  132   c  may be a conductive layer including a conductive material. The conductive material may include copper (Cu), nickel (Ni), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), lead (Pb), and/or alloys thereof. As necessary, the third electrode layers  131   c  and  132   c  may further include glass. The third electrode layers  131   c  and  132   c  may be formed by a method of dipping in a paste containing a conductive material or a method of printing a conductive paste containing a conductive material. However, exemplary embodiments are not limited thereto, and the third electrode layers  131   c  and  132   c  may be formed by a sheet transfer method, a pad transfer method, or the like. 
     The other contents are substantially the same as described in the above-described composite electronic component  500 A according to an exemplary embodiment and the above-described composite electronic component  500 B according to another exemplary embodiment, and redundant descriptions will be omitted. 
       FIG.  5    is a schematic cross-sectional view, illustrating another example of the composite electronic component of  FIG.  1   , taken along line I-I′ of  FIG.  1   . 
     Referring to  FIG.  5   , a composite electronic component  500 D according to another exemplary embodiment may include a ceramic electronic component  100  in which external electrodes  131  and  132  are disposed on a side surface and an upper surface of a body  110 , third electrode layers  131   c  and  132   c  are connected to internal electrodes  121  and  122 , first electrode layers  131   a  and  132   a  are disposed on a lower surface of the body  110 , and second electrode layers  131   b  and  132   b  are disposed on the third electrode layers  131   c  and  132   c  and the first electrode layers  131   a  and  132   a . For example, the first external electrode  131  may include a 3-1-th electrode layer  131   c , a 1-1-th electrode layer  131   a , and a 2-1-th electrode layer  131   b  as a plurality of electrode layers. The second external electrode  132  may include a 3-2-th electrode layer  132   c , a 1-2-th electrode layer  132   a , and a 2-2-th electrode layer  132   b  as a plurality of electrode layers. The 3-1-th electrode layer  131   c  may be connected to the plurality of first internal electrodes  121 . The 3-2-th electrode layer  132   c  may be connected to the plurality of second internal electrodes  122 . The third electrode layers  131   c  and  132   c  may be thicker than the first electrode layers  131   a  and  132   a , and the first electrode layers  131   a  and  132   a  may be thicker than the second electrode layers  131   b  and  132   b , but exemplary embodiments are not limited thereto. 
     The 3-1-th electrode layer  131   c  may be disposed on the first surface of the body  110  to extend partially upwardly of third to fifth surfaces of the body  110  or to extend partially upwardly of only a fifth surface of the body  110 , the 1-1-th electrode layer  131   a  may be disposed on a sixth surface of the body  110  to extend partially upwardly of the 3-1-th electrode layer  131   c , and the 2-1-th electrode layer  131   b  may be disposed on the 3-1-th electrode layer  131   c  and the 1-1-th electrode layer  131   a  to cover the 3-1-th electrode layer  131   c  and the 1-1-th electrode layer  131   a , but exemplary embodiments are not limited thereto. 
     The 3-2-th electrode layer  132   c  may be disposed on a second surface of the body  110  to extend partially upwardly of third to fifth surfaces of the body  110  or to partially upwardly of only a fifth surface of the body  110 , the 1-2-th electrode layer  132   a  may be disposed on a sixth surface of the body  110  to extend partially upwardly of the 3-2-th electrode layer  132   c , and the 2-2-th electrode layer  132   b  may be disposed on the 3-2-th electrode layer  132   c  and the 1-2-th electrode layer  132   a  to cover the 3-2-th electrode layer  132   c  and the 1-2-th electrode layer  132   a , but exemplary embodiments are not limited thereto. 
     Each of the first electrode layers  131   a  and  132   a  and the third electrode layers  131   c  and  132   c  may be directly disposed on at least one surface of the body  110 . For example, the 3-1-th electrode layer  131   c  may be directly disposed on the first surface of the body  110 , and a portion of the 3-1-th electrode layer  131   c  may be disposed to directly extend to the third to fifth surfaces of the body  110  or to directly extend to only the fifth surface of the body  110 . The 1-1-th electrode layer  131   a  may be directly disposed on the sixth surface of the body  110 , and at least a portion of The 1-1-th electrode layer  131   a  may be disposed to extend upwardly of the third-first electrode layer  131   c  to be in direct contact with at least a portion of the 3-1-th electrode layer  131   c . The 2-1-th electrode layer  131   b  may be directly disposed on the 3-1-th electrode layer  131   c  and the 1-1-th electrode layer  131   a . In addition, the 3-2-th electrode layer  132   c  may be directly disposed on the second surface of the body  110 , and a portion of the 3-2-th electrode layer  132   c  may be disposed to directly extend to the third to fifth surfaces of the body  110  or to directly extend to only the fifth electrode layer  132   c  A portion may be disposed to extend directly to only the fifth surface of the body  110 . The 1-2-th electrode layer  132   a  may be directly disposed on the sixth surface of the body  110 , and at least a portion of the 1-2-th electrode layer  132   a  may be disposed to extend upwardly of the 3-2-th electrode layer  132   c  to be in direct contact with at least portion of the 3-2-th electrode layer  132   c . The 2-2-th electrode layer  132   b  may be directly disposed on the 3-2 electrode layer  132   c  and the 1-2 electrode layer  132   a.    
     The third electrode layers  131   c  and  132   c  may be formed by dipping opposite end portions of the body  110  into a paste including a conductive material in a state in which the sixth surface of the body  110  is blocked with a barrier. Alternatively, the third electrode layers  131   c  and  132   c  may be formed by dipping opposite end portions of the body  110  in a paste including a conductive material and then removing a portion formed on the sixth surface of the body  110 . However, exemplary embodiments are not limited thereto, and the third electrode layers  131   c  and  132   c  may be formed by directly printing a conductive paste including a conductor on surfaces of opposite end portions of the body  110 , except for the sixth surface, using screen-printing, or the like. Alternatively, the third electrode layers  131   c  and  132   c  may be formed by attaching a conductor sheet or a conductor pad, for example, a copper sheet or a nickel sheet, to the first and second surfaces of the body  110 , respectively corresponding to head surfaces, drying the attached conductor sheet or the conductive pad, and directly printing a conductive paste including a conductor on the fifth surface of opposite end portions of the body  100 , corresponding to a top band, using screen-printing, or the like. Thus, the third electrode layers  131   c  and  132   c  having a substantially inverted L shape in a cross-section. 
     The first electrode layers  131   a  and  132   a  may be formed after the third electrode layers  131   c  and  132   c  are formed. For example, the first electrode layers  131   a  and  132   a  may be formed by forming the third electrode layers  131   c  and  132   c  and then directly printing a mixture material, including metal particles and an insulating resin, on the sixth surface of the body  110  corresponding to a bottom band using screen-printing. However, exemplary embodiments are not limited thereto, and the first electrode layers  131   a  and  132   a  may be formed by forming the third electrode layers  131   c  and  132   c  and then selectively dipping the sixth surface of the body  110 , corresponding to the bottom band, into a mixture material including metal particles and an insulating resin. Thus, the first electrode layers  131   a  and  132   a  having a substantially “-” shape in a cross-section. In addition, at least a portion of the first electrode layers  131   a  and  132   a  may be disposed to extend upwardly of the third electrode layers  131   c  and  132   c  to be in direct contact therewith, respectively. 
     The second electrode layers  131   b  and  132   b  may be formed after the third electrode layers  131   c  and  132   c  and the first electrode layers  131   a  and  132   a  are formed. For example, the second electrode layers  131   b  and  132   b  may be formed by performing a plating process on the electrode layers  131   a  and  132   a . As the plating process, an electrolytic plating process, an electroless plating process, or the like, may be used. Thus, the second electrode layers  131   b  and  132   b  may be directly disposed on the third electrode layers  131   c  and  132   c  and the first electrode layers  131   a  and  132   a.    
     In this regard, in a cross-section, the third electrode layers  131   c  and  132   c  may be directly disposed on the side and upper surfaces of the body  110 , and the first electrode layers  131   a  and  132   a  may be directly disposed on the lower surface of the body  110 . The second electrode layers  131   b  and  132   b  may be disposed on the third electrode layers  131   c  and  132   c  and the first electrode layers  131   a  and  132   a.    
     Here, “in a cross-section” may refer to a cross-sectional shape when an object is vertically taken in an X direction and a Z direction, or a cross-sectional shape when the object is viewed in a side view based on a Y direction. 
     As described above, when the third electrode layers  131   c  and  132   c  are formed by separately forming layers in a head region and a top band region of the body  110 , the third electrode layers  131   c  and  132   c  may include a first region, directly disposed on the side surface of the body  110 , and a second region, directly disposed on the upper surface of the body  110 , in a cross-section. At least a portion of the second region may be disposed to extend upwardly of the first region to be in direct contact with at least a portion of the first region. The first region and the second region may be regions separated from each other and having a boundary surface with each other. 
     The other contents are substantially the same as described in the above-described composite electronic component  500 A according to an exemplary embodiment, the above-described composite electronic component  500 B according to another exemplary embodiment, and the above-described composite electronic component  500   c  according to another exemplary embodiment and redundant descriptions will be omitted. 
       FIG.  6    is a schematic cross-sectional view illustrating a mechanism in which thermal stress is generated inside a single piece of ceramic electronic component during a reflow process. 
     Referring to  FIG.  6   , a single piece of ceramic electronic component  100 ′ may include a body  110 ′, including a dielectric layer  111 ′ and an internal electrode  121 ′, and external electrodes  131 ′ and  132 ′ disposed on the body  110 ′. The body  110 ′ may further include an internal electrode (not illustrated) connected to the external electrode  132 ′, other than the internal electrode  121 ′ illustrated in the drawing. 
     Continuing to refer to  FIG.  6   , in a structure of the single piece of ceramic electronic component  100 ′, the internal electrode  121 ′ having a higher coefficient of thermal expansion (CTE) than the dielectric layer  111 ′ may exhibit a behavior of shrinkage toward a central portion. An internal electrode (not illustrated), connected to the external electrode  132 ′, may also exhibit a similar behavior of shrinkage. In addition, the external electrodes  131 ′ and  132 ′ having a higher coefficient of thermal expansion (CTE) than a dielectric material may have a behavior of pulling the dielectric layer  111 ′ from end portions of the external electrodes  131 ′ and  132 ′ while shrinking. Therefore, maximum tensile stress S 1  may be generated in the end portions of the upper and lower external electrodes  131 ′ and  132 ′ due to the shrinkage behavior of the internal electrodes  121 ′ and the dielectric pulling behavior resulting from the shrinkage of the external electrodes  131 ′ and  132 ′. 
       FIG.  7    is a schematic cross-sectional view illustrating a mechanism in which thermal stress is generated inside a composite electronic component. 
     Referring to  FIG.  7   , a composite electronic component  500 ′ may include a ceramic electronic component  100 ′ and an interposer  200 ′ coupled to the ceramic electronic component  100 ′. The composite electronic component  500 ′ may include a body  110 ′, including a dielectric layer  111 ′ and an internal electrode  121 , and external electrodes  131 ′ and  132 ′ disposed on the body  110 ′. The body  110 ′ may further include an internal electrode (not illustrated), connected to the external electrode  132 ′, other than the internal electrode  121 ′ illustrated in the drawing. The interposer  200 ′ may include a substrate  210 ′ and connection electrodes  231 ′ and  232 ′ disposed on the substrate  210 ′. The external electrodes  131 ′ and  132 ′ and the connecting electrodes  231 ′ and  232 ′ are connected through solders  331 ′ and  332 ′. 
     Continuing to refer to  FIG.  7   , in a structure of the composite electronic component  500 ′, a coefficient of thermal expansion (CTE) of the substrate  210 ′ is lower than that of the dielectric layer  111 ′ during reflow temperature reduction, so that the amount of shrinkage of the substrate  210 ′ is smaller than the amount of shrinkage of the dielectric layer  111 ′. Accordingly, the dielectric layer  111 ′ may act as a behavior of relatively expanding the substrate  210 ′. When the substrate  210 ′ expands relatively, a behavior of outwardly pushing the external electrodes  131 ′ and  132 ′ may occur. As a result, a behavior of dipping the dielectric layer  111 ′ in lower end portions of the external electrodes  131 ′ and  132 ′ may be increased, and thus, maximum tensile stress S 2  in the vicinity of the lower end portions may be further increased. 
       FIG.  8    is a simulation result illustrating maximum stress generated inside a chip during reflow of various types of composite electronic component, as compared with a single piece of ceramic electronic component. 
     In  FIG.  8   , “Normalized Max Chip Stress” represents a relative stress level compared with the structure of the single piece of ceramic electronic component  100 ′ illustrated in  FIG.  6   . For example, when the stress level is 1.15, it means that stress is 15% higher than that of the structure of the single piece of ceramic electronic component  100 ′. Experimental Example “1” is a simulation result in the structure of the composite electronic component  500 ′ illustrated in  FIG.  7   . In this case, the external electrodes  131 ′ and  132 ′ have a form in which a third electrode layer, including copper (Cu), and a second electrode layer, including a nickel (Ni) layer and a tin (Sn) layer, are sequentially formed. For example, the external electrodes  131 ′ and  132 ′ may not include the first electrode layer, a relatively flexible layer, but may include only these relatively rigid layers. In addition, Experimental Examples “2,” “3,” “4,” and “5” are simulation results in the structures of the composite electronic component  500 A according to an exemplary embodiment, the composite electronic component  500 B according to another exemplary embodiment, the composite electronic component  500 C according to another exemplary embodiment, and the composite electronic component  500 D according to another exemplary embodiment described in  FIGS.  2 ,  3 ,  4 , and  5   , respectively. 
     Referring to  FIG.  8   , in the case of Experimental Example “1,” the rigid external electrodes  131 ′ and  132 ′ have a relatively high modulus to obtain a thermal stress generation mechanism, so that internal stress is 15% higher than the structure of the single piece of ceramic electronic component  100 ′. On the other hand, in the cases of Experimental Examples “2,” “3,” “4,” and “5,” all of the external electrodes  131  and  132  include relatively flexible first electrode layers  131   a  and  132   a . When the substrate  210  relatively expands compared with the dielectric layer  111 , the relatively flexible first electrode layers  131   a  and  132   a  themselves are stretched, rather than the dielectric layer  111  being pulled, to eliminate a difference in coefficient of thermal expansion (CTE) between the ceramic electronic component  100  and the interposer  200 . Therefore, it can be seen that in Experimental Examples “2,” “3,” and “5” in which the relatively flexible first electrode layers  131   a  and  132   a  are directly introduced on the body  110 , maximum internal stress may be reduced to a level similar to that of the structure of the single piece of is the ceramic electronic component  100 ′. In particular, it can be seen that in the case of Experimental Example “5,” connectivity between the internal electrodes  121  and  122  and the external electrodes  131  and  132  may be secured and thermal stress caused by the difference in coefficient of thermal expansion (CTE) may be effectively reduced. In addition, it can be seen that in Experimental Example “4” in which relatively flexible first electrode layers  131   a  and  132   a  are introduced between the third electrode layers  131   c  and  132   c  and the second electrode layers  131   b  and  132   b , about 70% of an increase in internal stress caused by the attachment of the interposer  200  may be eliminated. 
     As described above, a composite electronic component, which may reduce thermal stress generated inside a ceramic electronic component, may be provided. 
     In the present disclosure, the terms “lower side”, “lower portion” , “lower surface,” and the like, have been used to indicate a direction toward a mounted surface of the electronic component package in relation to cross sections of the drawings, the terms “upper side”, “upper portion”, “upper surface,” and the like, have been used to indicate an opposite direction to the direction indicated by the terms “lower side”, “lower portion”, “lower surface,” and the like. However, these directions are defined for convenience of explanation only, and the claims are not particularly limited by the directions defined, as described above. 
     The meaning of a “connection” of a component to another component in the description includes an indirect connection through an adhesive layer as well as a direct connection between two components. In addition, “electrically connected” means including a physical connection and a physical disconnection. It can be understood that when an element is referred to as “first” and “second”, the element is not limited thereby. These terms may be used only for a purpose of distinguishing the element from the other elements, and may not limit the sequence or importance of the elements. In some cases, a first element may be referred to as a second element without departing from the scope of the claims set forth herein. Similarly, a second element may also be referred to as a first element. 
     The term “an example embodiment” used herein does not always refer to the same example embodiment, and is provided to emphasize a particular feature or characteristic different from that of another example embodiment. However, example embodiments provided herein are considered to be able to be implemented by being combined in whole or in part one with another. For example, one element described in a particular example embodiment, even if it is not described in another example embodiment, may be understood as a description related to another example embodiment, unless an opposite or contradictory description is provided therein. 
     Terms used herein are used only in order to describe an example embodiment rather than to limit the present disclosure. In this case, singular forms include plural forms unless necessarily interpreted otherwise, based on a particular context. 
     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 disclosure as defined by the appended claims.