KR20150051983A - Chip inductor - Google Patents

Abstract

The present invention relates to a chip inductor. The chip inductor according to the present invention includes a substrate on which a through hole is formed, a conductive coil which is formed on the substrate, a top resin complex magnetic layer which is filled to surround the conductive coil to form a core on the center of the substrate, a bottom resin complex magnetic layer which is formed on the lower side of the substrate, and an external electrode which is formed on both sides of the top and bottom resin complex magnetic layers.

Description

CHIP INDUCTOR

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip inductor, and more particularly, to a chip inductor having a substrate having a through-hole in an inductor.

In general, an inductor is a basic circuit element having self-inductance, and it can be composed of a coil and a core which is a magnetic body.

Inductors are one of the important passive components of electronic circuits together with resistors and capacitors. They are used as components to eliminate noise or to form LC resonance circuits. Such an inductor may be a multilayer type or the like manufactured by printing an internal electrode pattern on a wire-wound, magnetic or dielectric insulating sheet manufactured by winding a coil on a ferrite magnetic body or by printing an electrode on both ends, Can be classified.

The inductor thus constructed can be used in various systems such as a low noise amplifier, a mixer, a voltage-controlled oscillator, and a matching coil. In particular, a planar inductor is an inductor element implemented by a thin film conductor coil formed on a substrate. Filters and the like.

In recent years, techniques for forming a magnetic body together with a conductor coil of a thin film on a substrate have been developed in order to improve the performance of the inductor element. The performance of such an inductor is improved by a magnetic substance such as soft ferrite It is largely dominated by characteristics. At this time, the characteristics required for the magnetic body should have a sufficient magnetic permeability in a high frequency range in a high frequency application, not be deteriorated thermally and mechanically during the manufacturing process of the inductor, and be insulated from the conductor coil.

Japanese Patent Application Laid-Open No. 2000-243909

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems and disadvantages of the conventional inductors, and it is an object of the present invention to provide a magnetic inductor having a substrate in an inductor to serve as a gap, The present invention provides a chip inductor having improved characteristics.

The above object of the present invention can be achieved by a substrate having a through-hole formed therein; A conductor coil laminated on the upper surface of the substrate in a single layer or in multiple layers; An upper resin composite magnetic layer filled on the upper surface of the substrate so as to surround the conductor coil so that a core is formed at the center; A lower resin composite magnetic layer formed on the lower surface of the substrate and connected to the upper resin composite magnetic layer through the through hole; And an outer electrode formed on both sides of the upper and lower resin composite magnetic layers.

The substrate may be made of a non-magnetic material made of a resin or a ceramic material. In addition, the through-holes formed in the substrate may be formed at the central portion of the substrate or the four corners of the substrate or at the four corners of the substrate.

At this time, the substrate is preferably formed to a thickness of 50 탆 or less.

The upper and lower resin composite magnetic layers may be composed of a composite of a magnetic material of a metallic material and a polymer material, and may be composed of only ferrite. When the upper and lower resin composite magnetic layers are a composite of a magnetic material and a polymer material, metal powder may be mixed and uniformly distributed in the polymer.

At this time, the polymer material may be composed of epoxy, polyimide, LCP, or the like.

Meanwhile, an insulating layer may be further formed on the outside of the conductor coil. The insulating layer may be made of a polymer or other resin material having an insulating property and is insulated from metal powder contained in the filled upper resin composite magnetic layer so that the conductor coil is buried.

The chip inductor thus configured may be formed to extend in two directions symmetrical to the quadrant of the substrate so that the conductor coil is electrically connected to the external electrode surrounding the side surfaces of the upper and lower resin composite magnetic layers.

As described above, the chip inductor according to the present invention includes the substrate in the inductor, and the substrate can support both the conductor coil and the gap in the inductor, There is an advantage that a chip inductor can be manufactured.

Further, by forming a through hole at a predetermined position of a substrate embedded in a chip inductor, the magnetic flux density of the upper and lower resin composite magnetic layers can be increased through the through hole to realize a high inductance, and a DC bias characteristic can be improved There are advantages.

1 is a sectional view showing a manufacturing process of a chip inductor according to the present invention.
2 is a plan view of a substrate embedded in a chip inductor according to the present invention;
3 is a sectional view of another embodiment of a chip inductor according to the present invention.
4 is a plan view showing another embodiment of a substrate applied to a chip inductor according to the present invention.

The technical effect of the chip inductor according to the present invention, including the technical structure thereof, will be clearly understood from the following detailed description of the preferred embodiments of the present invention with reference to the drawings.

1 is a cross-sectional view illustrating a manufacturing process of a chip inductor according to the present invention, and FIG. 2 is a plan view of a substrate embedded in a chip inductor according to the present invention.

The chip inductor 100 according to the present invention includes a substrate 110, a conductor coil 120 wound on the substrate 110, and a conductive layer 120 formed on the substrate 110 to fill the conductive coil 120. [ And a lower resin composite magnetic layer 140 formed on the lower surface of the substrate 110. The upper resin composite magnetic layer 130 may be formed on the lower resin composite magnetic layer 130,

The outer electrode 150 may be further formed on the side surfaces of the upper and lower resin composite magnetic layers 130 and 140 including the substrate 110.

The substrate 110 may be made of a non-magnetic material made of a resin or a non-conductive material such as ceramics. In the case of a resin material, an FR4 substrate or a polyimide substrate may be used, and other polymer- , And the thickness of the substrate 110 is preferably 50 mu m or less. At this time, if the thickness of the substrate 110 exceeds 50 mu m, it may be difficult to form a thin chip inductor, so that it is preferable to design the thickness to be not more than 50 mu m.

In addition, the substrate 110 may have a through hole 111 at the center thereof. The through hole 111 may be formed in a circular shape, a square shape, or the like, and may have any shape other than a circular shape and a quadrangle shape and can pass through the top and bottom of the substrate.

The substrate 110 thus configured serves to support the conductor coil 120 and the upper resin composite magnetic layer 130 on the upper surface of the substrate 110 during the fabrication process. In addition, after the fabrication of the chip inductor, Role can be performed at the same time.

The conductive coil 120 may be formed on the upper surface of the substrate 110 on a peripheral upper surface except for the through hole 111 at the center. At this time, the conductor coil 120 may be formed as a single layer or a multilayer stacked on a peripheral upper surface except for the through-hole 111 of the substrate 110. The conductor coil 120 may be formed by a method such as electroplating or screen printing, and is preferably formed in the form of a helical coil made of copper.

By forming the conductive coil 120 in the form of a helical coil, it is possible to secure a low specific resistance and sufficient inductance.

The conductor coil 120 may have a spiral shape and may be formed as a single layer or a multilayer structure.

Meanwhile, the upper surface of the substrate 110 may be covered with the upper resin composite magnetic layer 130 so that the conductor coil 120 is embedded. For example, the upper resin composite magnetic layer 130 may be formed so as to cover and cover the portion of the conductor coil 120 formed on the upper surface of the substrate 110 except for the surface of the conductor coil 120 that is joined to the substrate. The upper resin composite magnetic layer 130 may be filled with a sufficient height to be able to embed the conductor coil 120, and the upper resin composite magnetic layer 130 may be formed of ferrite alone.

The ferrite plating method can be used for forming the magnetic layer using ferrite, and the thickness of the magnetic layer can be precisely controlled through the ferrite plating apparatus of the spin spray method, and the thickness uniformity can be ensured. In addition, since such a spin spray process can be performed at a relatively low temperature of 100 ° C or less, the thermal influence on the substrate or the conductor coil 120 can be minimized.

In addition to ferrite, it may be composed of any one of Mo-permalloy, permoloy, Fe-Si-Al alloy, Fe-Si alloy and amorphous metal.

The upper resin composite magnetic layer 130 may be formed by dispersing one metal powder selected from Fe, Ni, Zn, Co, Ba, Sr, and Mn in a polymer. At this time, a resin material such as epoxy, polyimide, and LCP may be used as the polymer.

In addition, a lower resin composite magnetic layer 140 may be formed under the substrate 110 to cover the lower surface of the substrate. At this time, the lower resin composite magnetic layer 140 is connected to the upper resin composite magnetic layer 130 through the through hole 111 of the substrate 110. The lower resin composite magnetic layer 140 may be made of the same material as the upper resin composite magnetic layer 130 formed on the substrate 110. That is, the upper resin composite magnetic layer 130 surrounding the conductor coil 120 and the conductor coil 120 is formed on the upper surface of the substrate 110, and the conductor coil 120 The lower resin composite magnetic layer 140 can be formed.

An insulating layer 160 may be further formed on the substrate 110 so as to surround the outer circumferential surface of the conductive coil 120. The insulating layer 160 may be formed of gold (Au) Layered conductor coil 120 composed of copper (Cu) is contacted with the upper resin composite magnetic layer 130 to prevent the upper and lower layers from affecting the inductor characteristics.

That is, the insulating layer 160 may be formed when the upper resin composite magnetic layer 130 is composed of a material in which the metal powder is dispersed and mixed in the polymer. The insulating layer 160 may be made of a resin material other than a polymer or polymer having an insulating property and may be formed by interposing an upper resin composite magnetic layer 130 in which metal powder is mixed between layers of the multilayer conductor coil 120 So that the upper resin composite magnetic layer 130 is not interposed between the layers.

Therefore, if the resin composite magnetic layer 130 formed on the substrate 110 is made of an insulating material without mixing the metal powder, the insulating layer 160 may not be separately provided.

External electrodes 150 may be formed on both sides of the chip inductor 100. The outer electrode 150 is formed in order to allow the chip inductor 100 to be electrically connected. The outer electrode 150 may be formed by forming upper and lower resin composite magnetic layers 130 and 140 on a substrate 110 and then dipping or dispensing As shown in FIG.

At this time, the external electrode 150 may be electrically connected to the conductive coil 120. The conductor coil 120 is formed in the form of a coil around the core portion of the upper resin composite magnetic layer 130 for electrical connection with the external electrode 150 and is formed on both sides of the quadrant, And may be extended symmetrically to both left and right sides. The conductive coil 120 extending outside the quadrant of the substrate 110 may be electrically connected to the external electrode 150.

The upper and lower resin composite magnetic layers 130 and 140 may have high resistivity and high permeability. Since the resin composite magnetic layer 130 is formed at a position very close to the conductor coil 120, the quality characteristics of the inductor can be improved, and a thin and thin thickness can be achieved while realizing high inductance.

The chip inductor 100 of this embodiment configured as described above has a structure in which the direction of the magnetic path in the core portion formed in the central portion of the upper resin composite magnetic layer 130 formed on the substrate 110 is formed through the through hole 111 of the substrate 110 Since it acts from the top to the bottom or from the bottom to the top, the magnetic flux density can be increased in the inductor, thereby improving the inductance and improving the DC bias characteristic.

3 is a cross-sectional view of another embodiment of a chip inductor according to the present invention, and FIG. 4 is a plan view showing another embodiment of a substrate applied to a chip inductor according to the present invention.

As shown in the figure, the chip inductor 100 of the present embodiment is composed of the substrate 110, the conductor coil 120, and the upper and lower resin composite magnetic layers 130 and 140 in the same manner as the above- External electrodes 150 may be formed on both sides of the composite magnetic layers 130 and 140.

In this case, the same reference numerals are given to the same constituent elements as those of the previously described embodiment, and a detailed description that can be duplicated for the same constituent elements will be omitted.

The substrate 110 embedded between the upper and lower resin composite magnetic layers 130 and 140 of the present embodiment should be formed of a nonmagnetic material using a resin material or a nonconductive material made of a ceramic material and have at least one through hole 112 formed on four corners of each side, Can be formed.

As shown in FIG. 4, the through-hole 112 may be formed to have a curved surface toward the center of the substrate 110, but may have another shape capable of forming a through-hole, that is, And the shape of the through-hole may be changed depending on the arrangement form of the conductor coil 120 formed on the substrate 110. [

In addition, the chip inductor 100 of the present invention may have a structure in which a through hole is formed at the center and four corners of the substrate 110.

In addition, the substrate 110 is preferably formed to have a thickness of 50 탆 or less for designing a thin inductor. The substrate 110 supports the conductive coil 120 and the upper resin composite magnetic layer 130, Thereby enabling the role of a gap layer in the inductor to be performed.

On the other hand, the conductor coil 120 may be formed on the upper surface of the substrate 110 at a central portion excluding the through-holes 112 on the four corners. At this time, the conductor coil 120 is formed on the upper surface of the substrate 110 excluding the central portion of the core forming portion, and may be formed by a method such as electroplating or screen printing, and is preferably formed in the form of a helical coil made of copper Do.

The upper resin composite magnetic layer 130 may be formed on the substrate 110 on which the conductor coil 120 is formed and the lower resin composite magnetic layer 140 may be formed on the lower surface of the substrate 110. External electrodes 150 may be further formed on both sides of the upper and lower resin composite magnetic layers 130 and 140 including the substrate 110 to electrically connect the chip inductor 100.

The chip inductor 100 of this embodiment configured as described above has a magnetic path direction of the upper and lower resin composite magnetic layers 130 and 140 through the through holes 112 formed at the four corners formed on the substrate 110, Since it acts from the top to the bottom or from the bottom to the top, the magnetic flux density in the inductor can be increased to improve the inductance, and the DC bias characteristic can be improved.

Meanwhile, when the characteristics of the chip inductor are simulated using the substrate 110 applied to the present embodiment, the results are as follows.

The through hole shape of the substrate Inductance (uH) DC bias (A) Example 1

0.85

3.5 Example 2

0.94

3.8 Example 3

1.05

4.0

As shown in the simulation results of Table 1, it can be seen that the characteristics of the inductance Ls and the DC bias are improved compared to the conventional chip inductors in which the substrate is made of a flat plate for each embodiment have. Table 1 shows the results of the case where the sizes of the through holes 111 of the substrate 110 are different and the shapes and sizes of the through holes 112 formed at the four corners of the substrate 110 are different Inductance (Ls) and DC bias characteristics are shown.

That is, in the case of a conventional chip inductor in which a substrate having a through-hole is applied as in the case of the first to third embodiments, the inductance Ls of the substrate is about 0.6 uH and the DC bias is 3.0 A, As the inductance is measured from 0.85 to 1.05 uF according to the shape, it can be seen that the capacitance is increased as compared with the conventional chip inductor using the plate type substrate.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

100. Chip inductor 110. Substrate
111, 112. Through hole 120. Conductor coil
130. Upper resin composite magnetic layer 140. Lower resin composite magnetic layer
150. Outer electrode 160. Insulation layer

Claims (14)

A substrate having a through-hole formed therein;
A conductor coil laminated on the upper surface of the substrate in a single layer or in multiple layers;
An upper resin composite magnetic layer filled on the upper surface of the substrate so as to surround the conductor coil so that a core is formed at the center;
A lower resin composite magnetic layer formed on the lower surface of the substrate and connected to the upper resin composite magnetic layer through the through hole; And
And outer electrodes formed on both sides of the upper and lower resin composite magnetic layers.
The method according to claim 1,
Wherein the substrate is made of a nonmagnetic material made of a resin or a ceramic material.
3. The method of claim 2,
And the through-hole formed in the substrate is formed at a central portion.
The method according to claim 1,
Wherein the upper and lower resin composite magnetic layers are composed of a composite of a magnetic material of a metallic material and a polymer material.
The method according to claim 1,
Wherein the upper and lower resin composite magnetic layers are made of ferrite and are any of metal materials such as Mo-permalloy, permalloy, Fe-Si-Al alloy, Fe-Si alloy and amorphous metal.
The method according to claim 1,
And an insulating layer is further formed on the outer side of the conductor coil to insulate the upper resin composite magnetic layer from the conductor coil.
The method according to claim 1,
Wherein the conductor coil is extended in two directions symmetrical to the quadrant of the substrate, and is electrically connected to the external electrode.
The method according to claim 1,
Wherein the through-hole has a chip inductor in which at least one through-hole is further formed at four corners of the substrate,
A substrate having one or more through-holes formed on four corners thereof;
A conductor coil laminated on the upper surface of the substrate in a single layer or in multiple layers and formed in the form of a helical coil;
An insulating layer formed on the outside of the conductor coil;
An upper resin composite magnetic layer filled on the upper surface of the substrate so as to surround the conductor coil so that a core is formed at the center;
A lower resin composite magnetic layer formed on the lower surface of the substrate and connected to the upper resin composite magnetic layer through the through hole; And
External electrodes formed on both sides of the upper and lower resin composite magnetic layers;
/ RTI >
10. The method of claim 9,
The upper and lower resin composite magnetic layers are composed of a composite material in which a magnetic material of a metallic material and a polymer material are divided centering on the substrate and the upper resin composite magnetic layer and the lower resin composite magnetic layer are made of the same material, .
10. The method of claim 9,
Wherein the substrate is made of a nonmagnetic material made of a resin or a ceramic material.
10. The method of claim 9,
Wherein the upper and lower resin composite magnetic layers are made of ferrite and are any of metal materials such as Mo-permalloy, permalloy, Fe-Si-Al alloy, Fe-Si alloy and amorphous metal.
10. The method of claim 9,
Wherein the conductor coil is extended in two directions symmetrical to the quadrant of the substrate, and is electrically connected to the external electrode.
10. The method of claim 9,
And the through-hole is further formed at a central portion of the substrate.

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