KR20170088155A - Coil component - Google Patents

Abstract

The present invention provides a coil component, comprising: a magnetic body; and an inner coil embedded in the magnetic body and including a first coil pattern and a second coil pattern disposed on an upper surface of the first coil pattern. The interval (a) between the first coil patterns is larger than the interval (b) between the second coil patterns. The present invention can provide the coil component having a high reliability by reducing a short-circuit defect.

Description

Coil Components {COIL COMPONENT}

The present invention relates to coil components, for example, to power inductors.

The inductor, which is one of the coil parts, is a passive element that removes noise by forming an electronic circuit together with a resistor and a capacitor.

In recent years, miniaturization and thinning of IT devices such as various communication devices and display devices have been accelerated. Researches for miniaturization and thinning of various devices such as inductors, capacitors, and transistors employed in IT devices have been continuously carried out . Accordingly, the inductor has been rapidly switched to a chip capable of miniaturization and high density automatic surface mounting, and thin film type inductors formed by mixing magnetic powder and resin on the coiled lead wire by plating have been developed.

The thin film type inductor that forms the inner coil pattern on the upper and lower surfaces of the insulating substrate as described above has a smaller chip size and thus reduces the space between the coils among the finest structure shapes of the inner coils and uniformly shapes the coils There is a need.

On the other hand, it is difficult to control the coil growth when the coil is formed by plating. In particular, when the plating is formed, the shape of the anisotropic plating growth depends on the shape of the lower coil as the base of the anisotropic plating growth. It is true.

The following Patent Document 1 discloses a thin-film chip inductor which forms an inner coil pattern by plating on the upper and lower surfaces of an insulating substrate. However, there is a problem that it is difficult to secure a sufficient space for forming an inner coil pattern.

Japanese Patent Application Laid-Open No. 2007-067214

An object of the present invention is to provide a coil component having a high reliability by reducing a short-circuit defect while exhibiting a low DC resistance (Rdc) by increasing the cross-sectional area of the inner coil.

According to one example of the present invention, there is provided a coil component comprising a magnetic body and an inner coil embedded therein.

The inner coil includes a first coil pattern and a second coil pattern disposed thereon. In this case, the spacing distance between the first coil patterns is controlled to be larger than the spacing between the second coil patterns.

According to an embodiment of the present invention, there is provided a coil component providing an inner coil having a high aspect ratio (AR).

According to one example of the present invention, there is provided a coil component that increases the cross-sectional area of the inner coil to exhibit a low DC resistance (Rdc).

According to an embodiment of the present invention, there is provided a coil component in which reliability of the coil component is minimized by minimizing the residual of minute foreign matter between the inner coils.

According to an embodiment of the present invention, there is provided a coil component in which the risk of occurrence of short failure even when overgrowth occurs on the inner coil is reduced.

1 is a schematic perspective view according to an example of the present invention.
2 is a cross-sectional view taken along line I-I 'of FIG.
3 is a cross-sectional view according to a modification of Fig.

Hereinafter, embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Accordingly, the 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 are the same elements.

It is to be understood that, although the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Will be described using the symbols.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

Hereinafter, a coil component according to an exemplary embodiment of the present invention will be described, but the present invention is not limited thereto.

Coil parts

FIG. 1 is a schematic perspective view of a coil part according to one example of the present invention, and FIG. 2 is a sectional view taken along line I-I 'of FIG.

A coil component 100 according to an exemplary embodiment of the present invention includes a magnetic body 1, an inner body 21 including a first coil pattern 21 embedded in the magnetic body and a second coil pattern 22 disposed thereon, And a coil (2).

The magnetic body 1 has a first surface and a second surface facing each other in the direction of the thickness T and a third surface facing the first surface in the length L direction, But may be substantially cubic, including, but not limited to, a fourth surface.

The magnetic body 1 forms an appearance of a coil part, and is not limited as long as it is a material exhibiting magnetic properties, and may be formed by filling, for example, ferrite or a metal-based soft magnetic material.

The magnetic body 1 may include an insulating substrate 3, and the insulating substrate is not particularly limited as long as it is formed of a thin film and is capable of forming the inner coil 2 by plating, For example, a PCB substrate, a ferrite substrate, a metal-based soft magnetic substrate, or the like.

The central portion of the insulating substrate 3 penetrates to form a hole, and the hole may be filled with a magnetic material such as ferrite or a metal soft magnetic material to form a core portion. The inductance L can be improved by forming the core portion filled with the magnetic material.

An inner coil 2 having a coil-shaped pattern may be formed on one surface of the insulating substrate 3 and an inner coil 2 having a coil-shaped pattern may be formed on the other surface of the insulating substrate 3 have.

A coil pattern may be formed in a spiral shape on the inner coil 2. An inner coil formed on one surface of the insulating substrate 3 and an inner coil formed on the other surface may be electrically connected to a via electrode formed on the insulating substrate 3 As shown in Fig.

Referring to FIG. 1, an external electrode facing the longitudinal direction may be disposed on the outer surface of the magnetic body. The outer electrode may include a first outer electrode connected to one end of the inner coil and a second outer electrode connected to the other end of the inner coil. The external electrode may be formed using a paste containing a metal having excellent electrical conductivity. For example, the external electrode may be formed of a metal such as nickel (Ni), copper (Cu), tin (Sn) Or the like, and the like. The method of forming the external electrode may be performed by not only printing but also dipping according to the shape of the external electrode.

Referring to FIG. 2, the inner coil 2 may include a first coil pattern 21 formed on an insulating substrate and a second coil pattern 22 disposed on the first coil pattern.

The first coil pattern 21 may be a patterned plating layer formed by forming a plating resist patterned on an insulating substrate 3 and filling the opening with a conductive metal.

The first coil pattern 21 may be formed by performing electroplating, and may be an isotropic plating layer having a shape that simultaneously grows in the width W direction and the height direction T of the coil, but the present invention is not limited thereto.

 Also, the second coil pattern 22 may be formed by performing electroplating, and may be an anisotropic plating layer which is formed while the growth in the width direction is more developed than the growth in the thickness direction of the coil. However, the present invention is not limited thereto.

The growth tendency of the first and second coil patterns 21 and 22 can be controlled by adjusting the current density, the concentration of the plating solution, the plating rate, and the like.

The spacing a between the first coil patterns 21 is larger than the spacing b between the second coil patterns 22.

In order to form a coil component having a high aspect ratio (AR) by promoting the growth of the thickness direction coil by the conventional plating method, the space between the lower coil patterns is narrowly set Respectively. However, if the interval between the lower coil patterns is narrowed, the shape of the upper coil pattern of the anisotropic plating growth disposed thereon is changed according to the shape of the lower coil pattern as the base of the anisotropic plating growth. As a result, when the distance between the lower coil patterns is narrowed, the distance between the upper coil patterns grown by the anisotropic plating becomes narrower, and if the upper coil pattern is grown in the width direction, there is a high risk of short failure .

In addition, when the distance between the lower coil patterns is narrowed by the conventional plating method, there is a high possibility that the remnants of the CCL and the plating solution do not escape by washing with water, adversely affecting the reliability of the coil parts.

The spacing a between the first coil patterns 21 is larger than the spacing b between the second coil patterns 22 in accordance with the coil component 100 of the present invention .

As a result, a short between the coils can be prevented even if the side of the second coil pattern is worn out, and the CCL remaining at the time of etching before the formation of the second coil pattern is removed to improve the shortness between the first coil patterns It is possible to improve the reliability adverse effect caused by the fine particles.

Table 1 below shows the degree of short-circuit occurrence and the DC resistance (Rdc) characteristics as the spacing a between the first coil patterns and the spacing b between the second coil patterns are changed.

Sample a [占 퐉] b [탆] Short
Degree[%] Rdc [mΩ] Example 1 3 3 50 47 Example 2 5 3 40 49 Example 3 10 5 10 50 Example 4 15 5 2 51 Example 5 20 8 0 53 Example 6 30 8 0 55 Example 7 40 9 0 60 Example 8 50 9 0 65

As can be seen from Table 1, it is preferable that the distance a between the first coil patterns is not less than 3 μm and not more than 40 μm. When the distance a between the first coil patterns is smaller than 3 mu m, the probability of occurrence of a short failure due to the narrow gap is more than 50%, so that almost all of the short failure problems may occur. The flow of the Cu plating liquid is high at the portion where the one coil pattern is disposed, so that the lateral overhang occurs during the anisotropic plating growth of the second coil pattern, or a high Rdc may occur.

The distance a between the first coil patterns is more preferably 15 m or more and 30 m or less. When the distance a between the first coil patterns is 15 m or more, the probability of occurrence of short defects is almost zero, When the thickness is 30 μm or less, reliability can be completely improved and the degree of Rdc can not be greatly increased.

The distance b between the second coil patterns is preferably smaller than the distance a between the first coil patterns and larger than 3 mu m. If the distance b between the second coil patterns is larger than 3 占 퐉, the short defects can be greatly reduced, which can be an effect exerted because the side overshoot of the second coil pattern does not occur.

The first coil pattern 21 and the second coil pattern 22 disposed thereon may be stacked on one surface of the insulating substrate 3 in order and the first coil pattern 22 and the second coil pattern 22 may be laminated on the other surface of the insulating substrate 3, Two coil patterns 21 and 22 may be formed. In this case, the first and second coil patterns disposed on one surface of the insulating substrate may be electrically connected through the first and second coil patterns disposed on the other surface of the insulating substrate and the via electrodes formed on the insulating substrate.

2, the width of the lower region of the second coil pattern 22 is formed to be smaller than the width of the central region. This is because the second coil pattern 22 has a shape in which the central region is convexly formed. When the central region of the second coil pattern 22 is convex, the width of the lower region adjacent to the first coil pattern can be made equal to the width of the first coil pattern, A stable arrangement relationship of the lower region of the second coil pattern can be derived. The center area of the second coil pattern has a convex shape so that the distance between the second coil patterns is smaller than the distance between the first coil patterns, It is possible to realize an anisotropic plating growth which is capable of realizing a dense structure in a coil component and capable of improving Rdc while solving the problem of remaining plating solution caused by narrowness.

Next, Fig. 3 is a schematic cross-sectional view of a coil component having a structure in which the thin film conductor layer 21a is disposed on the lower surface of the first coil pattern of Fig.

Referring to FIG. 3, a thin film conductor layer may be disposed on the lower surface of the first coil pattern 21. The thin film conductor layer may be a copper (Cu) thin film layer disposed on the bottom surface of the first coil pattern when the first coil pattern is formed. When a first coil pattern is formed using a plating resist, for example, only a thin film layer having the same cross section as the lower surface of the first coil pattern is left through chemical etching, and the other thin film layer should be removed, In the process, when a dense structure for narrowing the interval between the first coil patterns is formed, the thin film layer is not easily removed.

However, according to the embodiment of the present invention, by making the shapes between the first coil pattern and the second coil pattern different, reliability can be ensured between the first coil patterns so that the remnant of CCL remaining is hardly left , The second coil pattern minimizes the spacing therebetween to enable filling of the dense structure. For example, assuming that the total area of the lower space between the first coil patterns is 100 area%, the thin film conductor layer may be left only at 2% by area. In this case, The thin film conductor layer disposed in the first coil pattern can be said to be substantially not disposed on the space between the first coil patterns, whereby the reliability of the coil component can be greatly improved. More preferably, the shape of the lower surface of the first coil pattern and the shape of the upper surface of the thin-film conductor layer are substantially the same, so that the thin-film conductor layer may not remain in a space separated from the first coil pattern.

The first and second coil patterns may be formed of a metal having excellent electrical conductivity and may be formed of a metal such as Ag, Pd, Al, Ni, Ti, Au), copper (Cu), platinum (Pt), an alloy thereof, or the like.

According to an embodiment of the present invention, there is provided a semiconductor device having a high aspect ratio (AR), a cross-sectional area of an inner coil being increased to exhibit a low DC resistance (Rdc), minimization of minute foreign matter remaining between inner coils, And a risk of a short failure occurring even if overgrowth is caused on the upper portion of the inner coil is reduced.

The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited only by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

In the meantime, the expression "an example" used in this disclosure does not mean the same embodiment but is provided for emphasizing and explaining different unique features. However, the above-mentioned examples do not exclude that they are implemented in combination with the features of other examples. For example, although a matter described in a particular example is not described in another example, it may be understood as an explanation related to another example, unless otherwise stated or contradicted by that example in another example.

On the other hand, the terms used in this disclosure are used only to illustrate an example and are not intended to limit the present disclosure. Wherein the singular expressions include plural expressions unless the context clearly dictates otherwise.

100: Coil parts
1: inner coil
11: first coil pattern
12: second coil pattern
11a: thin film conductor layer
3: insulating substrate

Claims (10)

Magnetic body; And
An inner coil embedded within the magnetic body and including a first coil pattern and a second coil pattern disposed on an upper surface of the first coil pattern; / RTI >
Wherein a distance a between the first coil patterns is larger than an interval b between the second coil patterns,
Coil parts.
The method according to claim 1,
(A) between the first coil patterns is not less than 3 mu m and not more than 40 mu m,
Coil parts.
3. The method of claim 2,
(A) between adjacent first coil patterns is not less than 15 mu m and not more than 30 mu m,
Coil parts.
The method according to claim 1,
(B) between the second coil patterns is larger than 3 mu m and smaller than an interval (a) between the first coil patterns,
Coil parts.
The method according to claim 1,
Wherein the first coil pattern is formed by isotropic plating,
Coil parts.
The method according to claim 1,
Wherein the second coil pattern is formed by anisotropic plating,
Coil parts.
The method according to claim 1,
Wherein the second coil pattern is grown in both a width direction and a height direction,
Coil parts.
The method according to claim 1,
The width of the lower region of the second coil pattern is smaller than the width of the center region of the second coil pattern,
Coil parts.
The method according to claim 1,
A thin film conductor layer is disposed on a lower surface of the first coil pattern,
Wherein the thin film conductor layer has a total area of 2 area% or less when the total area of the lower space between the first coil patterns is 100 area%
Coil parts.
10. The method of claim 9,
Wherein a top surface shape of the thin film conductor layer is the same as a bottom surface shape of the first coil pattern,
Coil parts.

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