Patent Publication Number: US-11393625-B2

Title: Electronic component and method for manufacturing the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit under 35 USC 119 (a) of Korean Patent Application No. 10-2020-0066003 filed on Jun. 1, 2020 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. 
     TECHNICAL FIELD 
     The present disclosure relates to an electronic component and a method for manufacturing the same. 
     BACKGROUND 
     A multilayer ceramic capacitor (MLCC), a multilayer chip electronic component, is a chip-type condenser mounted on the printed circuit boards of various electronic products such as display devices including liquid crystal displays (LCDs) and plasma display panels (PDPs), computers, smartphones, cell phones, and the like, to allow electricity to be charged therein and discharged therefrom. 
     A multilayer ceramic capacitor (MLCC) is used in various types of electronic components since it is relatively small and may be easily mounted while implementing high capacitance. 
     With the recent trend for miniaturization and higher performance in electronic devices, multilayer ceramic capacitors have tended to be miniaturized and to have higher capacitance. Along with such a trend, the importance of reliability of multilayer ceramic capacitors has been increased and, in particular, the importance of moisture resistance reliability has been increased. 
     In the automobile industry, a greater number of multilayer ceramic capacitors have been required with the development of electric vehicles, autonomous vehicles, and the like. In addition, multilayer ceramic capacitors, used in automobiles and the like, are required to guarantee more severe moisture resistance reliability conditions. 
     SUMMARY 
     An aspect of the present disclosure is to provide an electronic component having improved moisture resistance reliability and a method for manufacturing the same. 
     An aspect of the present disclosure is to provide an electronic component having improved mountability and a method for manufacturing the same. 
     An aspect of the present disclosure is to provide an electronic component having improved productivity and reduced manufacturing costs and a method for manufacturing the same. 
     However, the objects of the present disclosure are not limited to the above description, and will be more easily understood in the process of describing specific embodiments of the present disclosure. 
     According to an aspect of the present disclosure, an electronic component includes an electronic component main body including a body, including a dielectric layer and an internal electrode, and an external electrode, disposed on the body, and a coating portion including a coating layer, disposed on an external surface of the electronic component main body, and a plurality of projections disposed on the coating layer. 
     According to an aspect of the present disclosure, a method for manufacturing an electronic component includes preparing an electronic component main body including a body, including a dielectric layer and an internal electrode, and an external electrode, disposed on the body, and forming a coating portion, including a coating layer disposed on an external surface of the electronic component main body and a plurality of projections disposed on the coating layer, using vapor deposition. 
     According to an aspect of the present disclosure, an electronic component includes an electronic component main body including a body and an external electrode disposed on the body, the body including a dielectric layer and an internal electrode, and a plurality of projections comprising an organic material and disposed on an external surface of the electronic component main body. 
    
    
     
       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 an electronic component according to an embodiment of the present disclosure. 
         FIG. 2  is a schematic perspective view of a body of the electronic component except for a coating portion in  FIG. 1 . 
         FIG. 3  is a cross-sectional view taken along line I-I′ in  FIG. 1 . 
         FIG. 4  is a schematic exploded perspective view of the body in  FIG. 2 , in which dielectric layers and internal electrodes are laminated. 
         FIG. 5  is an enlarged view of P region in  FIG. 3 . 
         FIG. 6  is an image, captured by an atomic force microscope (AFM), showing a surface of a coating portion disposed on a (1 μm×1 μm) region of a central portion of a second surface of a body of an electronic component according to an embodiment of the present disclosure in width and length directions (Y and X directions). 
         FIG. 7  is a graph illustrating surface roughness of a coating portion measured along a measurement line L 12  of  FIG. 6  using an atomic force microscope (AFM). 
         FIGS. 8A, 8B, and 8C  illustrate processes in which a coating portion according to the present disclosure is formed by vapor deposition. 
         FIG. 9  illustrates a coating portion formed when a deposition process is performed for a significantly long period of time, and illustrates a region corresponding to the region P in  FIG. 5 . 
         FIG. 10  is a graph illustrating contact angles in Table 1. 
         FIG. 11  is a graph illustrating centerline average roughness Ra in Table 1. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present disclosure will be described with reference to specific embodiments and the accompanying drawings. However, embodiments of the present disclosure may be modified to have various other forms, and the scope of the present disclosure is not limited to the embodiments described below. Further, embodiments of the present disclosure may be provided for a more complete description of the present disclosure to the ordinary artisan. Therefore, shapes and sizes of the elements in the drawings may be exaggerated for clarity of description, and the elements denoted by the same reference numerals in the drawings may be the same elements. 
     A value used to describe a parameter such as a 1-D dimension of an element including, but not limited to, “length,” “width,” “thickness,” “diameter,” “distance,” “gap,” and/or “size,” a 2-D dimension of an element including, but not limited to, “area” and/or “size,” a 3-D dimension of an element including, but not limited to, “volume” and/or “size”, and a property of an element including, not limited to, “roughness,” “density,” “weight,” “weight ratio,” and/or “molar ratio” may be obtained by the method(s) and/or the tool(s) described in the present disclosure. The present disclosure, however, is not limited thereto. Other methods and/or tools appreciated by one of ordinary skill in the art, even if not described in the present disclosure, may also be used. 
     In the drawings, portions not related to the description will be omitted for clarification of the present disclosure, and a thickness may be enlarged to clearly show layers and regions. Further, throughout the specification, when an element is referred to as “comprising” or “including” an element, it means that the element may further include other elements as well, without departing from the description, unless specifically stated otherwise. 
     In the drawings, an X direction may be defined as a second direction, an L direction, or a longitudinal direction; a Y direction may be defined as a third direction, a W direction, or a width direction; and a Z direction may be defined as a first direction, a stacking direction, a T direction, or a thickness direction. 
     Electronic Component 
       FIG. 1  is a schematic perspective view of an electronic component according to an embodiment of the present disclosure. 
       FIG. 2  is a schematic perspective view of a body of the electronic component except for a coating portion in  FIG. 1 . 
       FIG. 3  is a cross-sectional view taken along line I-I′ in  FIG. 1 . 
       FIG. 4  is a schematic exploded perspective view of the body in  FIG. 2 , in which dielectric layers and internal electrodes are laminated. 
       FIG. 5  is an enlarged view of P region in  FIG. 3 . 
     Hereinafter, an electronic component  1000  according to an embodiment of the present disclosure will be described with reference to  FIGS. 1 to 5 . 
     An electronic component  1000  according to an embodiment may include an electronic component main body  100 , including a body  110  including dielectric layers  111  and internal electrodes  121  and  122 , and external electrodes  131  and  132  disposed on the body  110 , and a coating portion  140  including a coating layer  140   a  disposed on an external surface of the electronic component main body  100  and a plurality of projections  140   b  disposed on the coating layer  140   a.    
     The electronic component main body  100  includes the body  110  and the external electrodes  131  and  132  disposed on the body  110 . 
     In the body  110 , the dielectric layers  111  and the internal electrodes  121  and  122  are alternately laminated. 
     Although a specific shape of the body  110  is not necessarily limited, as illustrated, the body  110  may have a hexahedral shape or the like. Due to shrinkage of ceramic powder particles contained in the body  110  during a sintering process, the body  110  may not have a perfectly hexahedral shape with completely straight lines, but may have a substantially hexahedral shape overall. 
     The body  110  may have first and second surfaces  1  and  2  opposing each other in a thickness direction (the Z direction), third and fourth surfaces  3  and  4  connected to the first and second surfaces  1  and  2  and opposing each other in a length direction (the X direction), and fifth and sixth surfaces  5  and  6  connected to the first and second surfaces  1  and  2 , connected to the third and fourth surfaces  3  and  4 , and opposing each other in a width direction (the Y direction). 
     A plurality of dielectric layers  111  forming the body  110  may be in a sintered state, and adjacent dielectric layers  111  may be integrated with each other such that boundaries therebetween are not readily apparent without using a scanning electron microscope (SEM). 
     According to an embodiment, a raw material for forming the dielectric layers  111  is not necessarily limited as long as sufficient capacitance may be obtained therefrom. For example, the raw material may be a barium titanate-based material, a lead composite perovskite-based material, a strontium titanate-based material, or the like. The barium titanate-based material may include BaTiO 3 -based ceramic powder particles. Examples of the ceramic powder particles may be (Ba 1-x Ca x )TiO 3 , Ba(Ti 1-y Ca y )O 3 , (Ba 1-x Ca x )(Ti 1-y Zr y )O 3  or Ba(Ti 1-y Zr y )O 3 , or the like, in which calcium (Ca), zirconium (Zr), or the like, is partially solid-solubilized in BaTiO 3 . 
     In addition to the ceramic powder particles, various ceramic additives, organic solvents, binders, dispersants, or the like, may be added as the raw material forming the dielectric layer  111 , depending on the purpose of the present disclosure. 
     The body  110  may include a capacitance forming portion, disposed in the body  110 , in which capacitance is formed, including the first and second internal electrodes  121  and  122  disposed to oppose each other with the dielectric layer  111  interposed therebetween, and an upper protection layer  112  and a lower protective layer  113 , respectively disposed above and below the capacitance forming portion. 
     The capacitive forming portion contributes to capacitance formation of a capacitor, and may be formed by repeatedly laminating a plurality of first and second internal electrodes  121  and  122  with respective dielectric layers  111  interposed therebetween. 
     The upper protective layer  112  and the lower protective layer  113  may be formed by laminating one or two or more dielectric layers on upper and lower surfaces of the capacitance forming portion in a vertical direction, respectively, and may serve to prevent the first and second internal electrodes  121  and  122  from being damaged by physical or chemical stress. 
     The upper protective layer  112  and the lower protective layer  113  may not include an internal electrode, and may include the same material as the dielectric layer  111 . 
     The internal electrodes  121  and  122  may include a first electrode  121  and a second internal electrode  122 . The first and second internal electrodes  121  and  122  are alternately disposed to oppose each other with respective dielectric layers  111 , constituting the body  110 , interposed therebetween, and may be exposed to the third and fourth surfaces  3  and  4  of the body  110 , respectively. 
     Referring to  FIGS. 2 and 4 , the first internal electrode  121  may be spaced apart from the fourth surface  4  and may be exposed to through the third surface  3 , and the second internal electrode  122  may be spaced apart from the third surface  3  and may be exposed through the fourth surface  4 . 
     In this case, the first and second internal electrodes  121  and  122  may be electrically separated from each other by respective dielectric layers  111  interposed therebetween. 
     Referring to  FIG. 4 , the body  110  may be formed by alternately laminating a ceramic green sheet, on which the first internal electrode  121  is printed, and a ceramic green sheet, on which the second internal electrode  122  is printed, and then sintering the laminated ceramic green sheets. 
     A material for forming the internal electrodes  121  and  122  is not necessarily limited, and a material having improved electrical conductivity may be used. For example, the internal electrodes  121  and  122  may be formed by printing a conductive paste for the internal electrodes including at least one of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof, on the ceramic green sheet. 
     A screen-printing method, a gravure printing method, or the like, may be used as a printing method of the conductive paste for the internal electrodes, but the present disclosure is not limited thereto. 
     The external electrodes  130  and  140  may be disposed on the body  110  and connected to the internal electrodes  121  and  122 , respectively. In addition, the external electrodes  130  and  140  may include first and second external electrodes  130  and  140 , respectively disposed on the third and fourth surfaces  3  and  4  of the body  110  to be connected to the first and second internal electrodes  121  and  122 . 
     Although the structure, in which the electronic component  100  includes two external electrodes  130  and  140 , has been described in this embodiment, the number, shape, and the like, of the external electrodes  130  and  140  may vary depending on the shape of the internal electrodes  121  and  122  or other purposes. 
     The external electrodes  131  and  132  may be formed of any material such as a metal, or the like, as long as it has electrical conductivity, and may be determined in consideration of electrical characteristics, structural stability, and the like. Moreover, each of the external electrodes  131  and  132  may have a multilayer structure. 
     For example, the external electrodes  131  and  132  may include electrode layers  131   a  and  132   a , disposed on the body  110 , and plating layers  131   b  and  132   b  formed on the electrode layers  131   a  and  132   a.    
     According to the present disclosure, organic acid and molten tin (Sn) may easily permeate the external electrodes  131  and  132  through a region of the coating layer  140   a , in which the projection  140   b  is not disposed, for example, a partially thin region of the coating portion  140  during a soldering process to improve mountability. Accordingly, even when the external electrodes  131  and  132  include the electrode layers  131   a  and  132   a  disposed on the body  110  and the plating layers  131   b  and  132   b  formed on the electrode layers  131   a  and  131   b  and the coating portion  140  is disposed on the plating layers  131   b  and  132   b , improved mountability may be implemented. 
     As a more detailed example of the electrode layers  131   a  and  132   a , each of the electrode layers  131   a  and  132   a  may be a sintered electrode, including a conductive metal and a glass, or a resin-based electrode including a conductive metal and a resin. 
     Alternatively or additionally, the electrode layers  131   a  and  132   a  may have a form in which a plastic electrode and a resin-based electrode are sequentially formed on a body. The electrode layers  131   a  and  132   a  may be formed by transferring a sheet, including a conductive metal, to the body or may be formed by transferring a sheet, including a conductive metal, to a sintered electrode. 
     A material having improved electrical conductivity may be used as the conductive metal included in the electrode layers  131   a  and  132   a , and the present disclosure is not limited thereto. For example, the conductive metal may be at least one of nickel (Ni), copper (Cu), and alloys thereof. 
     As a more detailed example of the plating layers  131   b  and  132   b , the plating layers  131   b  and  132   b  may be Ni plating layers or Sn plating layers, and may have a structure in which a Ni plating layers and a Sn plating layer are sequentially formed on the electrode layers  131   a  and  132   a , or a structure in which a Sn plating layer, a Ni plating layer, and a Sn plating layer are sequentially formed. Alternatively or additionally, the plating layers  131   b  and  132   b  may include a plurality of Ni plating layers and/or a plurality of Sn plating layers. 
     The coating portion  140  may include a coating layer  140   a , disposed on an external surface of the electronic component main body  100 , and a plurality of projections  140   b  disposed on the coating layer  140   a.    
     Since a body prepared by sintering ceramic powder particles is formed by high-temperature sintering, a metal oxide having high surface energy may be exposed externally. Therefore, a body surface is high in hydrophilicity and has a structure vulnerable to ion migration occurring through water condensed on the body surface under high-temperature and high-humidity conditions. The term “ion migration” refers to a phenomenon in which a conductive metal is dissolved and ionized on a surface, a boundary surface, and an inside of an insulator to migrate and precipitate. 
     A method of coating a material having low surface energy on a body surface has been proposed to prevent ion migration. However, since not only an external surface of the body but also an external electrode is coated, electrical connectivity of the external electrode is deteriorated. In addition, defects such as slipping or non-mounting may occur during a process of performing reflow soldering on a printed circuit board (PCB) using Sn. 
     Therefore, in the related art, a coating preventing portion is disposed to prevent a surface of an external electrode from being coated. After the coating is completed, the coating preventing portion is removed. Alternatively, a body and an external electrode are coated overall, and then a portion coated on the external electrode is separately removed. Accordingly, productivity may be decreased or manufacturing costs may be increased. 
     According to the present disclosure, since the coating portion  140  includes the coating layer  140   a  disposed on the external surface of the electronic component main body  100  and a plurality of projections  140   b  disposed on the coating layer  140   a , moisture resistance reliability may be improved, and mountability may be secured and electrical connectivity may be improved through a region of the coating layer  140  in which the projections  140   b  are not disposed. 
     Therefore, a process of preventing the coating portion  140  from being disposed on the external electrodes  131  and  132  or a process of removing the coating portion  140  formed on the external electrodes  131  and  132  is not required, and thus, productivity of the component  1000  may be improved and manufacturing costs may be reduced. 
     The coating layer  140   a  may basically seal pores or cracking of the body  100  to prevent moisture from permeating into the body  110  through the external surface of the body  100 . In addition, since organic acid or molten Sn may easily permeate into the external electrodes  131  and  132  through a region of the coating layer  140   a , in which the projection  140   b  is not disposed, for example, a partially thin region of the coating portion  140 , mountability may be improved. 
     According to the present disclosure, since the coating layer  140   a  may have a thin portion or a partially broken region, a sufficient moisture resistance reliability improvement effect may not be obtained by only the coating layer  140   a . However, since the plurality of projections  140   b  are disposed on the coating layer  140   a , sufficient moisture resistance reliability may be secured even in a high-temperature and high-humidity environment. 
     The coating layer  140   a  is disposed to be in contact with the external surfaces of the external electrodes  131  and  132 , and may be disposed to be in contact with a region of the external surface of the body  110  in which the external electrodes  131  and  132  are not disposed. 
       FIG. 6  is an image, captured by an atomic force microscope (AFM), of a surface of a coating portion disposed on a (1 μm×1 μm) region of a central portion of a second surface of a body of an electronic component according to an embodiment of the present disclosure in width and length directions (Y and X directions). As can be seen from  FIG. 6 , a height of a brightest portion is 3.5 nm, a height of a darkest portion is −3.0 nm, and a coating portion includes a coating layer (a dark portion) and a plurality of projections (a bright portion) disposed on the coating layer. 
     An average thickness of the coating portion  140  may be 5 to 30 nm. 
     When the average thickness of the coating portion  140  is less than 5 nm, it may be difficult to secure a contact angle of the coating portion  140  to water to 100 degrees or more. When the contact angle of the coating portion  140  is less than 100 degrees, the moisture resistance reliability improvement effect may be insufficient. 
     On the other hand, when the average thickness of the coating portion  140  is more than 30 nm, it may be difficult to implement a partially thin region in the coating portion. Therefore, it may difficult for the organic acid and molten tin (Sn) to permeate into the external electrodes  131  and  132  during the soldering process, which causes mountability to be deteriorated. In addition, the electrical connectivity of the external electrodes  131  and  132  may be deteriorated, and it may be difficult to implement a structure in which the coating portion  140  may include the coating layer  140   a  and the plurality of projections  140   b.    
     In one example, referring to  FIG. 6 , the average thickness of the coating portion  140  may be an average value of a coating portion thickness measured, using an ellipsometer, with respect to a certain line L 1  having a length of, for example, 400 nm selected in a (1 μm×1 μm) region of a central portion of a first or second surface of the body in width and length directions (Y and X directions). The ellipsometer is an instrument which may measure a difference in polarized states between incident light and reflected light on a surface of a thin film to measure a thickness, a reflective index, and the like, of the thin film. 
     At least one of the plurality of projections  140   b  may have a height tb of 3 nm or more. 
     When the height tb of at least one of the plurality of projections  140   b  is less than 3 nm, the average thickness of the coating portion  140  may be less than 5 nm and the moisture resistance reliability improvement effect may be insufficient. 
     The height tb of the projection may be measured by observing the surface of the coating portion with an atomic force microscope (AFM). 
     In one example, the height tb of the projection may be a difference Δt between a valley and a ridge in the graph of surface roughness measured, using an atomic force microscope (AMF), along the certain line L 1  having a length of 400 nm selected in the (1 μm×1 μm) region of a central portion of the first or second surface of the body in the width and length directions (the Y and X directions). 
     As can be seen from  FIG. 7 , a surface roughness graph obtained by measuring the surface roughness of the coating portion along the L 1  in  FIG. 6  with the atomic force microscope (AMF), a difference Δt between a valley and a ridge was 3.875 nm and a sufficient projection was formed. 
     In addition, the height tb of the projection  140   b  may be more than twice a thickness ta of the coating layer  140   a . This is because the height tb of the projection  140   b  may be, in detail, greater than or equal to twice the thickness ta of the coating layer  140   a  to allow the coating portion  140  to have an average thickness of 5 to 30 nm. 
     The centerline average roughness Ra of the surface of the coating portion may be 0.3 nm or more. 
     The centerline average roughness Ra of the surface of the coating portion may be a value obtained based on Equation 1 from the surface roughness graph measured, using an atomic force microscope (AMF), along the certain line L 1  having a length of 400 nm selected in the (1 μm×1 μm) region of a central portion of the first or second surface of the body in the width and length directions, as an example. For example, the centerline average roughness Ra is expressed in nm as a value obtained by dividing an area of the roughness by a measurement length based on the center line. In addition, since the centerline average roughness Ra was measured with respect to a line having a length of 400 nm, L in Equation 1 has a length of 400 nm and the centerline is a line in a horizontal axis direction in which a vertical axis is 0 in  FIG. 7 . 
     
       
         
           
             
               
                 
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     A contact angle of the coating portion  140  to water may be 100 degrees or more. This is because the moisture resistance reliability improvement effect may be insufficient when the contact angle of the coating  140  to the water is less than 100 degrees. 
     A width of the projection  140   b  does not need to be limited, but may be, for example, 30 to 100 nm. This is because the width of the projection  140   b  may be, in detail, 30 to 100 nm to allow the coating portion  140  to have an average thickness of 5 to 30 nm. 
     An area occupied by the plurality of projections  140   b  does not need to be limited, but may be, for example, 10 to 60% of the overall area of the coating portion  140 . This is because the area occupied by the plurality of projections  140   b  is, in detail, 10 to 60% of the overall area of the coating portion  140  to allow the coating portion  140  to have an average thickness of 5 to 30 nm. 
     The coating portion  140  may include at least one of a siloxane-based polymer and/or a fluorine-based polymer. The siloxane-based polymer and the fluorine-based polymer may have low surface energy and have a hydrophobic property to improve moisture resistance reliability. In addition, the siloxane-based polymer and the fluorine-based polymer may easily implement the coating portion  140  of the present disclosure using vapor deposition. In this case, the coating portion  140  may include an organic material or be made of an organic material. 
     Since the coating layer  140   a  and the projection  140   b  may be formed using a single process, they may include the same material. 
     A method for preparing the coating portion  140  is not necessarily limited, and the coating portion  140  may be formed using atomic layer deposition (ALD), molecular layer deposition (MLD), chemical vapor deposition (CVD), or the like. 
     The coating layer  140   a ′ may have one or more openings. This is because growth of the coating layer  140   a ′ may be insufficient in a certain region, and thus, may be present in a broken form, as illustrated in  FIG. 8B . 
     In this case, an area of the one or more openings may be 10% or less of an overall area of the coating layer  140   a ′. This is because, when the area of the one or more openings is greater than 10% of the overall area of the coating layer  140   a ′, moisture resistance reliability may be deteriorated. 
     Method for Manufacturing Electronic Component 
     Hereinafter, a method for manufacturing an electronic component according to another aspect of the present disclosure will be described in detail. However, descriptions overlapping those given in the electronic component will be omitted to avoid overlapping descriptions. 
     A method for manufacturing an electronic component according to another aspect of the present disclosure may include preparing an electronic component main body including a body, including a dielectric layer and an internal electrode, and an external electrode disposed on the body and forming a coating portion, including a coating layer disposed on an external surface of the electronic component main body and a plurality of projections disposed on the coating layer, using vapor deposition. 
     Preparing Electronic Component Main Body 
     A conductive paste for an internal electrode may be applied to a ceramic green sheet using a printing method, or the like, to print an internal electrode. A printing method of the conductive paste may be a screen-printing method, a gravure printing method, or the like, but the present disclosure is not limited thereto. 
     Ceramic green sheets, on which internal electrodes are printed, may be laminated and sintered to form a body  110 . The number of the laminated sheets, on which internal electrodes are printed, may be adjusted depending on capacitance of a capacitor. 
     External electrodes  131  and  132  may be formed on the body  110  to form an electronic component main body  100 . 
     The external electrodes  131  and  132  may be formed by forming electrode layers  131   a  and  132   a  on the body  110  and forming plating layers  131   b  and  132   b  on the electrode layers  131   a  and  132   a.    
     A method of forming the electrode layers  131   a  and  132   a  is not necessarily limited, and the electrode layers  131   a  and  132   a  may be formed by applying a paste including a conductive metal and a glass, a paste including a conductive metal and a resin, or the like. Alternatively or additionally, the electrode layers  131   a  and  132   a  may be formed by a method of transferring a sheet, including a conductive metal, to the body  110  or a method of transferring a sheet, including a conductive metal, to a sintered electrode. 
     Forming Coating Portion 
     A coating portion  140  may be formed on the external surface of the electronic component main body  100  using vapor deposition. 
     The vapor deposition for forming the coating portion  140  may be atomic layer deposition (ALD), molecular layer deposition (MLD), chemical vapor deposition (CVD), or the like. 
     When initiated chemical vapor deposition (iCVD), a type of CVD, is used, the formation of the coating portion  140  may be more easily implemented. This is because ALD, MLD, or the like, may cause a coating portion to have a uniformly significantly low thickness, so that it may be difficult to secure moisture resistance reliability while the coating portion includes a coating layer and a plurality of projections. Meanwhile, iCVD may implement a structure, in which a coating portion includes a coating layer and a plurality of projections, while implementing an appropriate thickness. 
     According to the iCVD, a monomer M of a polymer, constituting a coating portion  140  in a chamber, may be vaporized to form the coating portion  140  through a gas-phase polymerization reaction in which a polymerization reaction of the polymer and a film-forming process are simultaneously performed. An initiator I and a monomer M may be vaporized by the iCVD, so that a chain polymerization reaction may be performed using free radicals R in a gaseous phase to deposit the coating portion on a surface of the electronic component main body  100 . 
     As a detailed example, a monomer M of a siloxane-based polymer and/or a fluorine-based polymer may be vaporized in a gaseous phase to form the coating portion  140  through a gas-phase polymerization reaction in which a polymerization reaction of the polymer and a film-forming process are simultaneously performed. 
       FIGS. 8A, 8B, and 8C  illustrate processes in which a coating portion according to the present disclosure is formed by vapor deposition. 
     Referring to  FIG. 8A , a coating material  40   b  starts to be attached to a portion of a surface of a body  110  at the beginning of a deposition process. 
     Referring to  FIG. 8B , the coating material, attached to the portion of the surface of the body  110 , starts to be divided into a thin coating layer  140   a ′ and a projection  140   b ′ as the deposition process is performed. 
     Referring to  FIG. 8C , a coating portion  140  including a coating layer  140   a  and a plurality of projections  140   b  may be formed to obtain an electronic component  1000  as the deposition process is further performed. 
     When the deposition process is performed for a significantly low period of time, a coating portion  40  having a uniform thickness, in which a coating layer and a projection are not distinguished, may be performed and an average thickness of the coating portion  40  may be increased to deteriorate electrical connectivity of an external electrode, as illustrated in  FIG. 9 . 
     Time required for the deposition process needs to be appropriately adjusted such that the coating portion  140  may include a coating layer  140   a , disposed on an external surface of an electronic component main body  100 , and a plurality of projections  140   b  disposed on the coating layer  140 . 
     The coating layer  140   a ′ may have one or more openings. This is because, as illustrated in  FIG. 8B , growth of the coating layer  140   a ′ is insufficient in a certain region, and thus, the coating layer  140   a ′ may be present in a partially broken form. 
     In this case, an area of the one or more openings may be 10% or less of an overall area of the coating layer  140   a ′. This is because when the area of the one or more openings is greater than 10% of the overall area of the coating layer  140   a ′, moisture resistance reliability may be deteriorated. 
     Example 
     A siloxane-based polymer was vaporized to form a coating portion having an average thickness, listed in Table 1, on a surface of a capacitor chip through a vapor polymerization reaction. Thus, sample chips were prepared, and then a contact angle and centerline average roughness Ra of each of the samples were listed in Table 1. In addition, a poor mountability test was performed on the samples and test results were listed in Table 1. 
     An average thickness of a coating portion is an average value of a coating portion thickness measured, using an ellipsometer, with respect to a certain line L 1  having a length of 400 nm selected in a (1 μm×1 μm) region of a central portion of a second surface of a body in width and length directions (Y and X directions). 
     A contact angle was listed as an average of values obtained by measuring a contact angle to water in certain five points of the (1 μm×1 μm) region using a contact angle measurement instrument. 
     A centerline average roughness Ra was expressed in nm as a value obtained by dividing an area of the roughness by a measurement length based on the center line in a surface roughness graph measured, using an atomic force microscope (AFM), with respect to the measurement line. 
     Poor mountability indicates the number of poor-mountability sample chips. Twelve sample chips of each sample were soldered on a substrate. A case, in which tombstone occurred or both two external electrodes were not fixed, was determined to be poor. The term “tombstone” refers to a phenomenon in which one of the two external electrodes was lifted to cause a chip to rise. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Sample 
                 Average Thickness of 
                 Contact Angle 
                 Ra 
                 Poor 
               
               
                 No. 
                 Coating Portion (nm) 
                 (degree) 
                 (nm) 
                 Mountability 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 1 
                 0 
                 33 
                 0.152 
                 0/12 
               
               
                 2 
                 2 
                 85 
                 — 
                 — 
               
               
                 3 
                 3 
                 95 
                 — 
                 — 
               
               
                 4 
                 5 
                 104 
                 0.306 
                 0/12 
               
               
                 5 
                 10 
                 102 
                 — 
                 — 
               
               
                 6 
                 15 
                 107 
                  0.3565 
                 0/12 
               
               
                 7 
                 20 
                 103 
                 0.348 
                 0/12 
               
               
                 8 
                 25 
                 105 
                  0.3895 
                 0/12 
               
               
                 9 
                 35 
                 — 
                 — 
                 5/12 
               
               
                   
               
            
           
         
       
     
     In the case of Sample Nos. 1 to 3 in which an average thickness of a coating portion was less than 5 nm, a contact angle of 100 degrees or more could not be secured, so that moisture resistance reliability was deteriorated. 
     In the case of Sample No. 9 in which an average thickness of a coating portion was greater than 30 nm, poor mountability occurred. 
     Meanwhile, in the case of Sample Nos. 4 to 8 in which an average thickness of a coating portion was 5 to 30 nm, a contact angle is 100 degrees or more, so that moisture resistance reliability was improved and poor mountability did not occur. 
     Referring to  FIG. 10 , which is a graph illustrating contact angles in Table 1, and  FIG. 11  which is a graph illustrating centerline average roughness Ra in Table 1, it may be confirmed that a contact angle of 100 degrees or more may be stably secured from 5 nm, an average thickness of a coating portion, and centerline average thickness Ra of 0.3 nm or more may be stably secured. 
     As described above, a coating portion, including a coating layer and a plurality of projections disposed on the coating layer, may be disposed on an external surface of an electronic component main body to improve moisture resistance reliability. 
     In addition, mountability may be secured through a region of a coating portion in which a projection is not disposed. 
     Furthermore, a coating portion may be implemented using vapor deposition to improve productivity and to reduce manufacturing costs. 
     While 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.