Coil electronic component and method of manufacturing the same

A coil electrode component includes a body including magnetic metal material, a coil disposed in the body and having first and second lead parts respectively outwardly exposed through first and second surfaces of the body. A first plating electrode is formed on the first surface of the body and a further surface of the body connected to and extended from the first surface of the body, and connected to the first lead part. A second plating electrode is formed on the second surface of the body and a further surface of the body connected to and extended from the second surface of the body, and connected to the second lead part.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Korean Patent Application No. 10-2015-0032396 filed on Mar. 9, 2015, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND

The present disclosure relates to a coil electronic component and a method of manufacturing the same.

An inductor, an electronic component, is a representative passive element configuring an electronic circuit, together with a resistor and a capacitor, to remove noise.

Among these, the inductor is manufactured by forming a coil in a body and forming external electrodes connected to the coil on outer surfaces of the body.

In accordance with recent changes such as increased complexity, multifunctionalization, thinness, or the like of a device, an attempt to reduce thickness of an inductor continues. Thus, there is a need for a technology able to secure high performance and reliability despite the trend toward slimming inductors.

SUMMARY

An aspect of the present disclosure may provide a coil electronic component capable of preventing contact defects between a coil and external electrodes and improving inductance by increasing a volume of a body, and a method capable of economically and efficiently manufacturing the coil electronic component.

According to an aspect of the present disclosure, a coil electronic component may include a body including a magnetic metal material, and a coil disposed in the body and having first and second lead parts respectively outwardly exposed to first and second surfaces of the body. A first plating electrode is formed on the first surface of the body and a further surface of the body connected to and extending from the first surface of the body, and connected to the first lead part. A second plating electrode is formed on the second surface of the body and a further surface of the body connected to and extending from the second surface of the body, and connected to the second lead part.

The first and second surfaces may be disposed to oppose each other while forming end surfaces of the body, and the further surface connected to the first surface may be the same surface as the further surface connected to the second surface and be provided as a mounting surface of the coil electronic component.

Lengths of portions of the first and second plating electrodes formed on the first and second surfaces may be longer than vertical distances from the mounting surface to the first and second lead parts, respectively.

Each of the lengths of the portions of the first and second plating electrodes formed on the first and second surfaces may be shorter than a thickness of the body.

The coil electronic component may further include an insulating layer formed on regions of outer surfaces of the body except for regions of the body on which the first and second plating electrodes are formed.

The coil electronic component may further include a surface electrode layer formed on the mounting surface of the body.

A surface step may be formed at an edge of the body at which a surface of the body opposing the mounting surface and the first or second surface meet.

The coil electronic component may further include a marking pattern formed on the mounting surface of the body or a surface of the body opposing the mounting surface of the body, and an insulating layer formed on regions of outer surfaces of the body except for regions of the body on which the first and second plating electrodes and the marking pattern are formed.

The first and second plating electrodes may include one or more selected from the group consisting of silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), and tin (Sn).

The first and second plating electrodes may include a first plating layer which is in contact with the first and second lead parts, respectively, and second and third plating layers which are sequentially laminated on the first plating layer.

The first plating layer may be provided as a copper (Cu) plating layer, the second plating layer may be provided as a nickel (Ni) plating layer, and the third plating layer may be provided as a tin (Sn) plating layer.

The magnetic metal material may be provided in a particle form and be dispersed in a thermosetting resin.

The coil may include a first coil pattern disposed on one surface of an insulating substrate and a second coil pattern disposed on the other surface of the insulating substrate opposing the one surface of the insulating substrate.

According to another aspect of the present disclosure, a method of manufacturing a coil electronic component may include forming a coil having a first lead part and a second lead part. A body is formed by laminating magnetic sheets including a magnetic metal material on an upper portion and a lower portion of the coil. First and second plating electrodes are formed on outer surfaces of the body. The first plating electrode may be formed on a first surface of the body and a further surface of the body connected to and extending from the first surface of the body, and connected to the first lead part. The second plating electrode may be formed on a second surface of the body and a further surface of the body connected to and extending from the second surface of the body, and connected to the second lead part.

The method of manufacturing a coil electronic component may further include, before the forming of the first and second plating electrodes on the outer surfaces of the body, forming an insulating layer on regions of surfaces of the body except for regions of the body on which the first and second plating electrodes are formed.

The method of manufacturing a coil electronic component may further include, before the forming of the first and second plating electrodes on the outer surfaces of the body, forming a surface electrode layer on the mounting surface of the body.

The method of manufacturing a coil electronic component may further include, before the forming of the first and second plating electrodes on the outer surfaces of the body, forming a surface step at an edge of the body at which a surface of the body opposing the mounting surface of the body and the first or second surface meet, and forming an insulating layer on regions of surfaces of the body except for regions of the body on which the first and second plating electrodes are formed.

The method of manufacturing a coil electronic component may further include, before the forming of the first and second plating electrodes on the outer surfaces of the body, forming a marking pattern on the mounting surface of the body or a surface of the body opposing the mounting surface of the body, and forming an insulating layer on regions of surfaces of the body except for regions of the body on which the first and second plating electrodes and the marking pattern are formed.

The forming of the first and second plating electrodes may include forming a first plating layer which is in contact with the first and second lead parts, respectively, and sequentially forming second and third plating layers on the first plating layer.

DETAILED DESCRIPTION

Coil Electronic Component

Hereinafter, a coil electronic component according to an exemplary embodiment, particularly, a thin film type inductor will be described. However, the coil electronic component according to the exemplary embodiment is not necessarily limited thereto.

FIG. 1is a perspective view of a coil electronic component according to an exemplary embodiment,FIG. 2is a perspective view illustrating the coil electronic component according to an exemplary embodiment so that coil patterns of the coil electronic component are visible, andFIG. 3is a cross-sectional view taken along line I-I′ ofFIG. 1.

Referring toFIGS. 1 through 3, a thin film type inductor used in a power line of a power supplying circuit is disclosed as an example of the coil electronic component.

A coil electronic component100, according to an exemplary embodiment, may include a body50, a coil40buried in the body50, and plating electrodes84and85disposed on outer surfaces of the body50and connected to the coil40.

InFIG. 1, in the following description, a “length” direction refers to an “L” direction ofFIG. 1, a “width” direction refers to a “W” direction ofFIG. 1, and a “thickness” direction refers to a “T” direction ofFIG. 1.

The body50may contain a magnetic metal material51.

The magnetic metal material51may be a crystalline or amorphous metal containing any one or more selected from the group consisting of iron (Fe), silicon (Si), boron (B), chromium (Cr), aluminum (Al), copper (Cu), niobium (Nb), and nickel (Ni).

For example, the magnetic metal material51may be an Fe—Si—B—Cr based amorphous metal, but is not limited thereto.

The metal magnetic material51may have a particle diameter of about 0.1 μm to 30 μm, and two or more kinds of magnetic metal materials having different average particle diameters may be mixed together. In a case in which the two or more kinds of magnetic metal materials having different average particle diameters together to be used, a filling rate may be improved to secure high permeability, and efficiency deterioration due to core loss at a high frequency and a high current may be prevented.

The magnetic metal material51may be provided in particle form and be dispersed and contained in a thermosetting resin such as an epoxy resin, a polyimide resin, or the like.

The coil40may be disposed in the body50and may have first and second lead parts respectively exposed to first and second surfaces of the body50.

The coil40may include a first coil pattern41formed on one surface of an insulating substrate20and a second coil pattern42formed on the opposing surface of the insulating substrate20. Here, the first lead part may be formed to be extended from one end portion of the first coil pattern, and the second lead part may be formed to be extended from one end portion of the second coil pattern.

The first and second coil patterns41and42may be formed in a spiral shape, and the first and second coil patterns41and42respectively formed on opposing surfaces of the insulating substrate20may be electrically connected to each other through a via (not illustrated) penetrating through the insulating substrate20.

The first and second coil patterns41and42may be formed on the insulating substrate20by performing electroplating, but are not limited thereto.

The first and second coil patterns41and42and the via may be formed of a metal having excellent electrical conductivity, such as silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), or alloys thereof.

The first and second coil patterns41and42may be coated with an insulating film (not illustrated) so as not to be directly in contact with the magnetic material forming the body50.

The insulating substrate20may be, for example, a polypropylene glycol (PPG) substrate, a ferrite substrate, a metal based soft magnetic substrate, or the like.

The insulating substrate20may have a through-hole formed in a central portion thereof to penetrate through the central portion thereof, wherein the through-hole may be filled with the magnetic material to form a core part55. The core part55filled with the magnetic material may be formed inside the coil40to improve inductance.

Although the coil40has been described as having the first and second coil patterns41and42formed on the insulating substrate20by plating with reference toFIGS. 2 and 3, the form of the coil40is not limited thereto. For example, any form of the coil40may be used as long as it may be disposed in the body to generate magnetic flux by the current applied thereto.

The coil electronic component100, according to the exemplary embodiment, may include the plating electrodes84and85formed on outer surfaces of the body50.

Generally, the external electrodes84and85of the coil electronic component100may be formed of a conductive resin paste including a conductive metal and a resin. Here, as the conductive metal included in the conductive resin paste, silver (Ag) having low specific resistance has mainly been used. However, silver (Ag) has high material cost and frequently causes contact defects with the coil, thereby causing an excessive increase in contact resistance.

Further, in a case in which the external electrodes are formed of the conductive resin paste as described above, since it is difficult to adjust an application thickness of the conductive resin paste, the external electrodes may be formed to be thick, and a volume of the body may be reduced as much as an increased thickness of the external electrodes.

As a result, according to the exemplary embodiment, external electrodes, for instance, the plating electrodes84and85, are formed of the magnetic metal material51included in the body50by plating, and thus the material cost may be reduced and contact defects between the coil and the external electrodes may be prevented. In addition, since the external electrodes, for instance, the plating electrodes84and85of the coil electrode component100according to the exemplary embodiment are formed on surfaces of the body50by direct plating, the thickness of the external electrodes may be easily adjusted, and the external electrodes may be formed to be thinner, thereby increasing the volume of the body50. As a result, inductance, DC-bias characteristics, efficiency, and the like may be improved.

The plating electrodes84and85may include a first plating electrode84formed on a first surface of the body and a further surface of the body connected to and extending from the first surface of the body, and connected to the first lead part, and a second plating electrode85formed on a second surface of the body and a further surface of the body connected to and extending from the second surface of the body, and connected to the second lead part.

For instance, according to the present exemplary embodiment, since the plating electrodes84and85may be formed on four or fewer surfaces among surfaces of the body50, cost of manufacturing the plating electrodes may be saved. Also, as the number of surfaces on which the plating electrodes are formed is reduced, space may be secured, thereby further increasing the volume of the body50.

According to the exemplary embodiment, the first and second surfaces of the body may be disposed to oppose each other while forming end surfaces of the body, and the further surface connected to the first surface, which is the same surface as the further surface connected to the second surface, may be provided as a mounting surface of the coil electrode component.

For instance, the external electrodes84and85may be formed on only three surfaces among the surfaces of the body50, and the external electrodes84and85may not be formed on a surface opposing the mounting surface of the coil electronic component.

In a case in which electronic components are highly integrated in order to satisfy miniaturization of an electronic product, the external electrodes formed on the surface opposing the mounting surface of the coil electronic component100and a metal can portion covering the coil electronic component100may be in contact with each other, thereby causing a problem such an occurrence of a short circuit, malfunction of the electronic product, or the like.

However, according to the present exemplary embodiment, since the plating electrodes84and85are not formed on the surface opposing the mounting surface of the body50, the risk of a short circuit, or the like, may be reduced even if the coil electronic component100and the metal can portion covering the coil electronic component100are in contact with each other.

According to an exemplary embodiment, the distance in a thickness direction of portions of the first and second plating electrodes formed on the first and second surfaces may be longer than vertical distances between the mounting surface and the respective first and second lead parts.

According to an exemplary embodiment, the distance in the thickness direction of the portions of the first and second plating electrodes formed on the first and second surfaces may be shorter than a thickness of the body.

According to the present exemplary embodiment, since a distance between the metal can portion covering the coil electronic component100and the plating electrodes84and85is further increased, the possibility that the problem such as the occurrence of a short circuit or the like occur may be further reduced.

The first and second plating electrodes84and85of the coil electronic component100, according to the exemplary embodiment, may be formed of a conductive material, such as silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), tin (Sn), or alloys thereof.

Since the first and second plating electrodes84and85may be formed by plating, the first and second plating electrodes84and85may not include a glass component and a resin.

The first and second plating electrodes84and85of the coil electronic component100, according to the exemplary embodiment, may each include a first plating layer which is in contact with the first and second lead parts, and second and third plating layers which are sequentially formed on the first plating layer.

The first, second, and third plating layers may be a copper (Cu) plating layer, a nickel (Ni) plating layer, and a tin (Sn) plating layer, respectively, but are not limited thereto.

The copper (Cu) plating layer is formed as the first plating layer which is directly in contact with the body50, and thus the material cost may be saved and electrical conductivity may be improved.

By forming the tin (Sn) plating layer as the third plating layer, adhesion between the coil electronic component100and the solder when the coil electronic component100is mounted on the circuit board may be improved.

By forming the nickel (Ni) plating layer as the second plating layer, connectivity between the Cu plating layer, which is the first plating layer, and the Sn plating layer, which is the third plating layer, may be improved.

According to an exemplary embodiment, an insulating layer60may be formed on surfaces of the body50, and the insulating layer60may be formed on regions except for regions on which the first and second plating electrodes84and85are formed.

According to the present exemplary embodiment, an occurrence of plating blur in a region except for the regions on which the external electrodes84and85are formed may be prevented.

FIG. 4is a cross-sectional view of a coil electronic component according to another exemplary embodiment in a length-thickness (LT) direction of the coil electronic component.

Referring toFIG. 4, the coil electronic component100, according to another exemplary embodiment, may further include a surface electrode layer86formed on the mounting surface of the body50.

The surface electrode layer86may be formed on a portion of the mounting surface of the body50to further improve fixing strength of the plating electrodes84and85formed on the mounting surface.

The surface electrode layer86may be formed by applying a conductive paste by a printing method or by a thin film process such as sputtering, or the like, but is not limited thereto.

The surface electrode layer86may be formed of a metal having excellent electrical conductivity, such as silver (Ag) palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), or alloys thereof, etc.

In a case in which the surface electrode layer86is formed, the fixing strength of the plating electrodes84and85when the coil electronic component100is mounted on the circuit board may be further improved, but in a case in which there is no need to improve the fixing strength of the plating electrodes84and85, there is no need to form the surface electrode layer86.

In the coil electronic component100according to the exemplary embodiment, even though the surface electrode layer86is not formed, the external electrodes may be formed by the magnetic metal material51included in the body50by plating, and particularly, widths in which the external electrodes are extended to the mounting surface may be adjusted by adjusting the region on which the insulating layer60is formed.

In other words, in the coil electronic component100according to the exemplary embodiment, even if the surface electrode layer86is not formed, it may not be difficult to form the external electrodes by plating.

Configurations overlapping those of the coil electronic component according to the exemplary embodiment described above except for the configuration of the surface electrode layer86may be similarly applied.

FIG. 5is a cross-sectional view of a coil electronic component according to another exemplary embodiment in a length-thickness (LT) direction of the coil electronic component.

Referring toFIG. 5, the coil electronic component100according to another exemplary embodiment may have a surface step formed at an edge of the body50at which a surface of the body50opposing the mounting surface of the body50and the first or second surface meet.

According to the present exemplary embodiment, the risk of a short circuit, or the like, between the portions of the first and second plating electrodes84and85, formed on the first and second surfaces, and the metal can portion covering the coil electronic component100may be further reduced.

Configurations overlapping those of the coil electronic component according to the exemplary embodiment described above except for the configuration of the surface step may be similarly applied.

FIG. 6is a perspective view illustrating a coil electronic component according to another exemplary embodiment so that coil patterns of the coil electronic component are visible.

Referring toFIG. 6, the coil electronic component100, according to another exemplary embodiment, may include a marking pattern90formed on the mounting surface of the body50or the surface opposing the mounting surface of the body50. In this case, the insulating layer60may be formed on regions of the outer surface of the body50except for regions on which the first and second plating electrodes84and85and the marking pattern90are formed.

The marking pattern90is provided so that directionality may be recognized. AlthoughFIG. 6illustrates a case in which the marking pattern90is positioned on the surface opposing the mounting surface of the body50while having a quadrangular shape, the shape and the position of the making pattern90are not limited to those illustrated inFIG. 6.

Configurations overlapping with those of the coil electronic component according to the exemplary embodiment described above except for the configuration of the marking pattern90may be similarly applied.

Method of Manufacturing a Coil Electronic Component

Hereinafter, a method of manufacturing coil electronic component100according to an exemplary embodiment will be described.

After a via hole is formed in the insulating substrate20and a plating resist having an open part is formed on the insulating substrate20, the via hole and the open part may be filled with a conductive metal by plating to form the first and second coil patterns41and42, and a via46connecting the first and second coil patterns41and42to each other.

The first and second coil patterns41and42and the via46may be formed of a conductive metal having excellent electrical conductivity, such as silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), or alloys thereof.

However, a method of forming the coil40is not necessarily limited to the plating process as described above, and the coil may be formed of a metal wire. For example, any coil may be used as long as it is formed in the body to generate magnetic flux by current applied thereto.

An insulating film (not illustrated) coating the first and second coil patterns41and42may be formed on the first and second coil patterns41and42.

The insulating film (not illustrated) may be formed by a known method such as a screen printing method, an exposure and development process of a photo-resist (PR), a spray applying process, or the like.

A central portion of a region of the insulating substrate20on which the first and second coil patterns41and42are not formed may be removed to form a core part hole.

The insulating substrate20may be removed by performing mechanical drilling, laser drilling, sandblasting, a punching process, or the like.

Next, the body50may be formed by laminating magnetic sheets including the magnetic metal material51on an upper portion and a lower portion of the first and second coil patterns41and42.

The magnetic sheets may be manufactured in a sheet shape by preparing slurry by mixtures of the magnetic metal material51, and organic materials such as a thermosetting resin, a binder, a solvent, and the like, applying the slurry at a thickness of several tens of micrometers onto carrier films by a doctor blade method, and then drying the slurry.

The magnetic sheets may have a form in which the magnetic metal material51provided in particle form is dispersed in the thermosetting resin such as an epoxy resin, a polyimide resin, or the like.

The body50in which the coil40is embedded may be formed by laminating, compressing, and curing the magnetic sheets.

Here, the core part hole may be filled with a magnetic material to form a core part55.

As the method of manufacturing a coil electronic component of the coil electronic component according to the exemplary embodiment, a process of laminating the magnetic sheets to form the body50in which the coil40is embedded has been described, but the method of manufacturing a coil electronic component is not necessarily limited thereto. For example, any method may be used as long as it may form a magnetic metal material-resin composition in which the coil is embedded.

FIGS. 7A through 7Care views illustrating a process of forming plating electrodes84and85of a coil electronic component according to an exemplary embodiment.

Referring toFIG. 7A, the surface step may be formed at the edge of the body at which the surface opposing the mounting surface of the body and the first or second surface meet.

According to the exemplary embodiment, the problem such as an occurrence of a short circuit between the plating electrodes84and85and the coil electronic component100, or the like, may be prevented by the surface step.

Referring toFIG. 7B, the insulating layer60may be formed on the regions of the surface of the body50except for the regions on which the plating electrodes are formed.

When the plating electrodes of the coil electronic component100according to the exemplary embodiment are formed, in a case in which the body50including the magnetic metal material51is plated as it is, an overall surface of the body50as well as the regions on which the plating electrodes84and85are formed may be plated.

Thus, when the plating to form the external electrodes is performed, there is a need to prevent the regions except for the regions on which the plating electrodes84and85are formed from being plated by the magnetic metal material.

Therefore, according to an exemplary embodiment, before forming the first and second plating electrodes84and85on the surface of the body50by plating, the insulating layer60is formed on the regions except for the region on which the first and second plating electrodes84and85are formed and the plating is then performed, and thus an occurrence of a plating blur on the regions except for the region on which the plating electrodes are formed may be prevented.

Referring toFIG. 7C, the first and second plating electrodes84and85may be formed by plating the surface of the body50on which the insulating layer60is not formed.

According to an exemplary embodiment, the first and second plating electrodes84and85may be formed by directly plating the surface of the body50by the magnetic metal material51included in the body50.

Meanwhile, the method of manufacturing the coil electronic component may further include an operation of forming a surface electrode layer86on the mounting surface of the body, before forming the first and second plating electrodes on the outer surface of the body.

In addition, the method of manufacturing the coil electronic component may further include an operation of forming a marking pattern90on the mounting surface of the body or the other surface of the body opposing the mounting surface of the body, before forming the first and second plating electrodes on the outer surface of the body. In this case, the insulating layer may be formed on a region of the surface of the body except for regions on which the first and second plating electrodes and the marking pattern are formed.

A description of features overlapping with those of the coil electronic component according to the exemplary embodiment described above except for the above-mentioned description will be omitted.

As set forth above, according to the exemplary embodiments in the present disclosure, contact defects between the coil and the external electrodes is effectively suppressed, and thus an excessive increase in contact resistance may be prevented. Further, inductance, DC-bias characteristics efficiency, and the like may be improved by increasing the volume of the body.