Coil components

Abstract

To provide a coil component that can reduce the acoustic noise of the coil component. [Solution] The coil component of the present invention comprises a first body containing a first magnetic material, a second body containing a second magnetic material disposed on the upper surface of the first body, an insulating layer disposed on the upper surface of the second body, and a coil that is at least partially disposed within the second body and extends to the surface of the second body, wherein the saturation magnetostriction constant of the first magnetic material is smaller than the saturation magnetostriction constant of the second magnetic material.

Description

Technical Field

[0001] The present invention relates to coil components.

Background Art

[0002] When a periodic pulse current is applied to a coil component, if it matches the resonance frequency of the entire substrate and mounted components, a resonance phenomenon may occur. Such amplified vibrations may cause acoustic noise by the entire substrate and may cause interference depending on the usage environment. Therefore, reducing acoustic noise is one of the important issues for coil components in sensitive applications.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a coil component that reduces the noise (acoustic noise) of the coil component.

Means for Solving the Problems

[0004] A coil component according to an aspect of the present invention made to achieve the above object includes a first main body including a first magnetic material, a second main body disposed on the upper surface of the first main body and including a second magnetic material, an insulating layer disposed on the upper surface of the second main body, and a coil at least partially disposed in the second main body and extending to the surface of the second main body, wherein the saturation magnetostriction constant of the first magnetic material is smaller than the saturation magnetostriction constant of the second magnetic material.

Effects of the Invention

[0005] According to the present invention, the noise (acoustic noise) of the coil component can be reduced.

Brief Description of the Drawings

[0006] [Figure 1]This is a perspective view showing a coil component according to the first embodiment of the present invention. [Figure 2] This is a schematic cross-sectional view showing the cross-section in the I-I' direction of Figure 1. [Figure 3] This is an enlarged view of the first example of areas A and B in Figure 2. [Figure 4] This is an enlarged view of the second example of areas A and B in Figure 2. [Figure 5] This is an enlarged view of the third example of areas A and B in Figure 2. [Figure 6] This is a cross-sectional view showing a first modified example of the first embodiment of the present invention. [Figure 7] This is a cross-sectional view showing a second modified example of the first embodiment of the present invention. [Figure 8] This is a cross-sectional view showing a third modified example of the first embodiment of the present invention. [Figure 9] This is a cross-sectional view showing a fourth modified example of the first embodiment of the present invention. [Figure 10] This is a perspective view showing a coil component according to a second embodiment of the present invention. [Figure 11] This is a schematic cross-sectional view of the II-II' direction in Figure 10. [Figure 12] This is a cross-sectional view showing a modified example of a second embodiment of the present invention. [Figure 13] This is a perspective view showing a coil component according to a third embodiment of the present invention. [Figure 14] This is a schematic cross-sectional view of the III-III' direction in Figure 13. [Figure 15] This is a cross-sectional view showing a modified example of a third embodiment of the present invention. [Figure 16] This is a cross-sectional view showing another modification of the third embodiment of the present invention. [Modes for carrying out the invention]

[0007] The terms used herein are used solely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “includes” or “having” are intended to specify the existence of features, figures, stages, actions, components, parts, or combinations thereof described in the specification, and should be understood not to preemptively exclude the possibility of the existence or addition of one or more other features, figures, stages, actions, components, parts, or combinations thereof. Throughout the specification, “above” means located above or below the part in question, and does not necessarily mean located above the direction of gravity.

[0008] Furthermore, the term "connection" shall not refer only to cases where each component is in direct physical contact with another component, but shall also encompass cases where other components are interposed between the components, and each component is in contact with the other components.

[0009] The dimensions and thicknesses of each component shown in the drawings are arbitrary for illustrative purposes, and therefore the present invention is not necessarily limited to those shown.

[0010] In the drawings, the X direction is defined as the first direction or length direction, the Y direction as the second direction or width direction, and the Z direction as the third direction or thickness direction.

[0011] Throughout the specification, "lamination direction" refers to the direction in which the components are sequentially stacked, and is the "thickness direction" perpendicular to the broad surface (main surface) of the components on the sheet, which corresponds to the Z direction (third direction) in the drawings.

[0012] Hereinafter, specific examples of embodiments for carrying out the coil component of the present invention will be described in detail with reference to the drawings. In the description with reference to the drawings, the same or corresponding components will be given the same reference numerals, and redundant explanations will be omitted.

[0013] Various types of electronic components are used in electronic devices, and various types of coil components are appropriately used between such electronic components for the purpose of noise removal and the like.

[0014] That is, in an electronic device, coil components are used for power inductors, high-frequency inductors, general beads, GHz beads, common mode filters, and the like.

[0015] ≪First Embodiment≫ The coil component 1000 according to the first embodiment is a thin-film type coil component.

[0016] FIG. 1 is a perspective view showing a coil component according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view schematically showing a cross-section in the I-I' direction of FIG. 1.

[0017] Referring to FIGS. 1 and 2, the coil component 1000 according to the first embodiment of the present invention includes a main body 100, a support member 200, a coil 300, external electrodes (400, 500), and an insulating layer 600, and further includes an insulating film IF.

[0018] The main body 100 forms the appearance of the coil component 1000 according to the present embodiment, and the coil 300 is embedded therein.

[0019] The main body 100 is formed in an overall hexahedral shape.

[0020] Hereinafter, on the premise that the main body 100 is in a hexahedral shape by way of example, embodiments of the present invention will be described. However, such a description does not exclude coil components including a main body formed in a shape other than a hexahedron from the scope of the present invention.

[0021] The main body 100 includes a first surface 101 and a second surface 102 facing each other in the X direction (first direction), a third surface 103 and a fourth surface 104 facing each other in the Y direction (second direction), and a fifth surface 105 and a sixth surface 106 facing each other in the Z direction (third direction). Each of the third to sixth surfaces (103, 104, 105, 106) of the main body 100 corresponds to a plurality of sides connecting the first surface 101 and the second surface 102 of the main body 100. When mounting the coil component 1000 according to this embodiment onto a mounting board such as a printed circuit board, the fifth surface 105 of the main body 100 is positioned to face the mounting surface of the mounting board and mounted onto the mounting board.

[0022] In this embodiment, the coil component 1000, which has external electrodes (400, 500) and an insulating layer 600 formed on the main body 100 as described later, is formed to have a length of 2.0 mm, a width of 1.2 mm, and a thickness of 0.65 mm, but is not limited thereto. On the other hand, the numerical values ​​for length, width, and thickness of the coil component described above exclude tolerances, and the actual length, width, and thickness of the coil component due to tolerances may differ from the above values.

[0023] Referring to Figure 2, the main body 100 includes a first main body 110 and a second main body 120 positioned on the first main body. The main body 100 is divided into the first main body 110 and the second main body 120 based on differences in the particle size distribution and composition of the metallic magnetism, as will be described later. The first main body 110 and the second main body 120 are each formed in a hexahedral shape, but are not necessarily limited to this.

[0024] The first body 110 is positioned below the second body 120. One side (bottom surface) of the first body 110 constitutes the fifth surface 105 of the body 100. The second body 120 is positioned on the other side (top surface) of the first body 110. Multiple sides of the first body 110 constitute part of multiple sides of the body 100.

[0025] The first body 110 is positioned below the coil 300. That is, the coil 300 is not located inside the first body 110. However, it is not limited to this, and as shown in the modified example described later, at least a part of the coil 300 may be located inside the first body 110.

[0026] The second body 120 is positioned on the other side (top surface) of the first body 110. One side (bottom surface) of the second body 120 is in contact with the first body 110. The other side (top surface) of the second body 120 constitutes the sixth surface 106 of the body 100. The multiple sides of the second body 120, together with the multiple sides of the first body 110, constitute the multiple sides (103, 104, 105, 106) of the body 100.

[0027] An insulating layer 600, which will be described later, is placed on the upper surface of the second body 120. That is, the second body 120 forms the upper region of the body 100 and is positioned above the other body components (first body, third body).

[0028] At least a portion of the coil 300 is placed inside the second body 120. The second body 120 includes a core that penetrates the coil 300.

[0029] Figures 3 to 5 are enlarged views of various examples of areas A and B in Figure 2.

[0030] Referring to Figure 3(a), the first body 110 comprises a first magnetic material 11 and a resin. The first body 110 shows a structure in which the first magnetic material 11 is dispersed in the resin. The first body 110 contains two or more types of magnetic material dispersed in the resin. Here, different types of magnetic material means that the magnetic material dispersed in the resin is distinguished from one another by any one of the following: average diameter, composition, crystallinity, and shape. As an example, as shown in Figure 3, the first magnetic material 11 contains a large number of magnetic particles with different particle diameters.

[0031] On the other hand, as will be described later, the main body 100 may further contain a fourth magnetic material 14, the fourth magnetic material 14 having a saturation magnetostriction constant greater than that of the first magnetic material 11. For the sake of explanation, the fourth magnetic material 14 is not shown in Figure 3, but this does not exclude the case in which the first main body 110 of the present invention contains the fourth magnetic material 14.

[0032] The first body 110 contains a resin. The resin includes, but is not limited to, epoxy, polyimide, liquid crystal polymer, etc., either alone or in combination.

[0033] Similarly, the second body 120 comprises a second magnetic material 12 and a resin, and exhibits a structure in which the second magnetic material 12 is dispersed in the resin. A detailed explanation is omitted as it would overlap with that of the first body 110.

[0034] In the coil component 1000 according to this embodiment, the first body 110 and the second body 120 contain magnetic materials with different saturation magnetostriction constants.

[0035] Magnetostrictive effect refers to the phenomenon in which the physical size (length or volume) of a magnetic material changes when it is magnetized by a magnetic field. The main material of coil components generally exhibits magnetostrictive properties at the level of approximately 20 ppm (parts per million). For example, the saturation magnetostrictive constant of Fe-3.5%Si is 7.8 ppm, the saturation magnetostrictive constant of Fe-based amorphous materials is 20-30 ppm, and the saturation magnetostrictive constant of Fe-50%Ni is at the level of 25 ppm.

[0036] Therefore, the length of the magnetic material changes in accordance with the flow of magnetic flux within the coil component, and such changes can occur periodically, synchronized with changes in the external magnetic field. In particular, if a periodic pulse is applied to the coil component, this can cause vibrations. These vibrations cause minute deformations in the substrate via the external electrodes, and if they match the resonant frequency of the substrate or mounted components, the amplified vibrations can generate acoustic noise. The magnitude of this noise is proportional to the amplitude of the substrate, and the magnitude of the amplitude is proportional to the magnitude of the magnetostriction of the magnetic material.

[0037] Therefore, possible methods for reducing the acoustic noise of coil components include adjusting the magnetostrictive constant of the magnetic material and minimizing magnetostriction through structural changes in the coil component. In particular, adjusting the magnetostrictive constant and magnetic flux density in the lower part of the coil component adjacent to the substrate is effective.

[0038] In the coil component according to the present invention, the coil 300 is positioned such that it is deflected toward the upper surface of the main body. Specifically, referring to Figure 2, the distance d1 from the upper surface of the coil 300 to the other surface (upper surface) of the second main body 120 is smaller than the distance d2 from the lower surface of the coil 300 to one surface (lower surface) of the first main body 110. By increasing the area through which the magnetic flux passes in the lower part of the coil 300, the magnetic flux density in the lower part of the coil 300 can be reduced.

[0039] The magnetostrictive constant is a physical constant that indicates the degree to which a magnetic material deforms due to a magnetic field. Using a magnetic material with a small magnetostrictive constant reduces the physical deformation that occurs at a given magnetic field strength, thus reducing noise.

[0040] In the coil component according to the present invention, the saturation magnetostriction constant of the first magnetic material 11 is smaller than that of the second magnetic material 12. Because the saturation magnetostriction constant of the first magnetic material 11 is smaller than that of the second magnetic material 12, the magnetostrictive phenomenon occurring at the bottom of the coil component can be reduced, and noise (acoustic noise) can be effectively controlled.

[0041] Specifically, the saturation magnetostriction constant of the first magnetic material 11 is either a negative value or less than 1 ppm (parts per million). In particular, if the saturation magnetostriction constant of the first magnetic material 11 is a negative value, the magnetostrictive phenomenon caused by other magnetic materials such as the fourth magnetic material 14 can be canceled out.

[0042] In contrast, the saturation magnetostriction constant of the second magnetic material 12 has a positive value, specifically a value greater than 1 ppm.

[0043] On the other hand, if the first body 110 includes a first magnetic material 11 and a fourth magnetic material 14, it is not necessary for both the first magnetic material 11 and the fourth magnetic material 14 to have saturation magnetostriction constants smaller than those of the second magnetic material 12. For example, if the saturation magnetostriction constant of the first magnetic material 11 is sufficiently small, the magnetostrictive phenomenon described above can be reduced.

[0044] Similarly, when the first body 110 includes a first magnetic material 11 and a fourth magnetic material 14, it is not necessary for both the first magnetic material 11 and the fourth magnetic material 14 to have negative saturation magnetostriction constants or to have a value of 1 ppm or less. For example, if the saturation magnetostriction constant of the first magnetic material 11 is negative, the magnetostrictive phenomenon described above can be reduced.

[0045] The saturation magnetostriction constant of the magnetic material of the present invention can be measured by the following method. First, cross-sectional samples of the first body 110 and the second body 120 are taken. The cross-sectional sample is obtained from one cross-section of the body 100, for example, from a cross-section in the second-third direction (YZ) obtained by cutting the body 100 midway in the first direction (X direction) with reference to Figure 2. Using the coil 300 as the reference, samples of the second body 120 and the first body 110 are taken from the upper and lower regions of the obtained cross-section, respectively. The saturation magnetostriction constant is the average value of the values ​​measured for multiple magnetic materials in the cross-sectional sample. Alternatively, it can be calculated by averaging multiple values ​​measured in multiple cross-sections. Here, the multiple cross-sections are taken at regular intervals along one direction (for example, five cross-sections at intervals of 100 μm).

[0046] An AC or DC magnetic field is applied to the collected sample, and the magnetic field strength is changed in steps. The deformation (length) of the magnetic material that occurs at this time is measured using a piezoelectric element (electromagnetic method) or a laser interferometer (optical method), etc. As an example of a piezoelectric element, a PZT piezoelectric element or a CMUT (capacitor-based ultrasonic piezoelectric element) can be used. For the laser interferometer, a helium-neon (He-Ne) laser interferometer can be used.

[0047] When a magnetic field is applied, the deformation length ΔL in the saturated state is measured using a piezoelectric element or a laser interferometer. Given that the deformation length is ΔL and the original length is L0, the saturation magnetostriction constant (λS) is:

number

[0048] However, as mentioned above, it is not necessary to directly measure the saturation magnetostriction constant; the magnitudes of the saturation magnetostriction constants can be compared indirectly, as follows.

[0049] As an example, the saturation magnetostriction constant value of a magnetic material can be determined by analyzing the components that make up the magnetic material and the content of each component. As will be described later, the components and content of the magnetic material can be identified by TEM-EDS (Transmission Electron Microscopy with Energy Dispersive Spectroscopy) or SEM (Scanning Electron Microscope) analysis of a cross-section of the main body 100.

[0050] As another example, since the saturation magnetostriction constant of the first magnetic material 11 is smaller than the saturation magnetostriction constant of the second magnetic material 12, when samples of the first body 110 and the second body 120 are taken and a magnetic field is applied under the same conditions, the degree of deformation of the first magnetic material 11 may be smaller than the degree of deformation of the second magnetic material 12.

[0051] Below, we will first describe the first magnetic material 11, and then describe the second magnetic material 12.

[0052] As an example, the first magnetic material 11 is an alloy powder containing Fe and Si. Specifically, the first magnetic material 11 is at least one of the following: Fe-Si alloy powder, Fe-Si-Al alloy powder, Fe-Cr-Si alloy powder, Fe-Si-B amorphous alloy powder, Fe-Si-B-Cr amorphous alloy powder, Fe-Si-B-Cr amorphous alloy powder, Fe-Si-B-Cr-C amorphous alloy powder, Fe-Si-BP amorphous alloy powder, and Fe-Si-B-Cu-Nb nanocrystalline alloy powder.

[0053] The first magnetic material 11 contains 6.5 wt% or more of silicon (Si) relative to its total weight. When the silicon (Si) content is 6.5 wt% or more relative to the total weight, the magnetostrictive constant has a negative value. When the silicon (Si) content is less than 6.5 wt%, the saturated magnetostrictive constant has a positive value. As an example, Fe-6.5%Si alloy and Fe-8%Si-2%Cr alloy have magnetostrictive constant values ​​close to 0.

[0054] Preferably, the first magnetic material 11 contains 8 wt% or less of Si (silicon) relative to its total weight. If the Si (silicon) content exceeds 8 wt%, a high Si content increases magnetic anisotropy, which may lead to a decrease in permeability, an increase in the absolute value of the magnetostrictive constant, and potentially greater vibration. Furthermore, the saturation magnetic flux density (Bs) of the material may decrease, leading to a decrease in DC superposition characteristics and a deterioration in static current characteristics, which is undesirable.

[0055] In contrast, the second magnetic material 12 contains less than 6.5 wt% Si (silicon) by weight. The second magnetic material 12 has a positive saturation magnetostriction constant.

[0056] As an example of a method for analyzing the components constituting the above Fe-based alloy and the content of each component, TEM-EDS (Transmission Electron Microscopy with Energy Dispersive Spectroscopy) or SEM (Scanning Electron Microscope) analysis can be used on one cross-section of the main body 100. More specifically, using Figure 2 as a reference, the composition of the Fe alloy contained in the magnetic material can be obtained through images obtained from cross-sections in the second-to-third directions (YZ) obtained by cutting the main body 100 midway in the first direction (X direction), and the average value for multiple magnetic particles analyzed at multiple equally spaced points (for example, 5 points) in one cross-section can be calculated. Alternatively, the average value can be calculated after performing such an analysis process on multiple cross-sections of the magnetic body.

[0057] As an example, the first magnetic material 11 includes nanocrystals and amorphous materials. Specifically, the nanocrystals are Fe-based alloys and form alloys with boron (B), silicon (Si), niobium (Nb), phosphorus (P), carbon (C), copper (Cu), etc. In the nanocrystals, more than 30% by volume consists of fine crystalline particles of nanometer size within the amorphous matrix, and the average crystal size of the nanocrystals is 50 nm or less. The matrix is ​​amorphous and has a positive magnetostrictive constant, but because the precipitated nanocrystalline material has a negative magnetostrictive constant, the magnetostrictive constants cancel each other out, resulting in a low magnetostrictive value.

[0058] As an example, referring to Figure 4(a), the first magnetic material 11 contains first pure iron particles. The first main body 110 further contains a fourth magnetic material 14.

[0059] The first pure iron particles are, for example, CIP (carbonyl iron powder). In the case of pure iron particles, they have a negative magnetostriction constant at -7 ppm and a high saturation magnetic flux density (Bs), which minimizes the degradation of Isat. The first pure iron particles have a particle diameter of 0.1 μm to 10 μm, making them relatively small magnetic particles.

[0060] The fourth magnetic material 14 has a saturation magnetostriction constant that is greater than that of the first magnetic material 11.

[0061] As mentioned above, the magnetostrictive direction of pure iron is opposite to that of typical magnetic particles. Therefore, when the main body 110 contains two or more types of magnetic materials (11, 14), the magnetostrictive phenomenon can be reduced by including pure iron particles.

[0062] In contrast, the second body 120 does not contain pure iron particles as the second magnetic material 12. Alternatively, even if the second body 120 contains pure iron particles, the amount of pure iron particles is less than that of the first body 110.

[0063] When the main body (110, 120) contains two or more types of magnetic materials, the magnetostrictive phenomenon can be reduced by increasing the content of pure iron particles. Therefore, the magnetostrictive phenomenon at the bottom of the coil component can be reduced by increasing the content of pure iron particles in the first main body 110 compared to the content of pure iron particles in the second main body 120.

[0064] Referring to Figures 4(a) and 4(b), the area ratio occupied by the first pure iron particles 11 in the cross-section of the first body 110 is greater than the area ratio occupied by the second pure iron particles 12 in the second body 120.

[0065] The area ratio of pure iron particles present within the main body (110, 120) can be measured in the cross-sections of the main body 100 in the first to third directions. Specifically, multiple equally spaced regions (for example, 10 regions) in the third direction are imaged using a scanning electron microscope, with respect to the cross-sections of the main body 100 passing through the center in the first to third directions. The area ratio is calculated by determining the area occupied by pure iron particles per unit area using an image analysis program or similar tool. The area ratio is the arithmetic mean of the area ratios calculated for multiple regions.

[0066] As an example, referring to Figure 5(a), the first body 110 contains only pure iron particles as the first magnetic material 11. That is, the first body 110 does not contain any other magnetic material other than pure iron particles. In such a case, even if the volume of the first body 110 is small (i.e., even if the content of pure iron particles is small), the magnetostrictive phenomenon at the bottom of the coil 300 can be effectively controlled.

[0067] The second magnetic material 12 includes ferrite or metallic magnetic particles.

[0068] Ferrites include, for example, spinel-type ferrites such as Mg-Zn, Mn-Zn, Mn-Mg, Cu-Zn, Mg-Mn-Sr, and Ni-Zn; hexagonal ferrites such as Ba-Zn, Ba-Mg, Ba-Ni, Ba-Co, and Ba-Ni-Co; garnet-type ferrites such as Y-type; and Li-based ferrites, at least one of these.

[0069] The metallic magnetic particles include one or more selected from the group consisting of iron (Fe), silicon (Si), chromium (Cr), cobalt (Co), molybdenum (Mo), aluminum (Al), niobium (Nb), copper (Cu), and nickel (Ni). For example, the metallic magnetic particles are at least one of the following: pure iron powder, Fe-Si alloy powder, Fe-Si-Al alloy powder, Fe-Ni alloy powder, Fe-Ni-Mo alloy powder, Fe-Ni-Mo-Cu alloy powder, Fe-Co alloy powder, Fe-Ni-Co alloy powder, Fe-Cr alloy powder, Fe-Cr-Si alloy powder, Fe-Si-Cu-Nb alloy powder, Fe-Ni-Cr alloy powder, Fe-Cr-Al alloy powder, Fe-Si-B amorphous alloy powder, Fe-Si-B-Cr amorphous alloy powder, Fe-Si-B-Cr amorphous alloy powder, Fe-Si-BP amorphous alloy powder, and Fe-Si-B-Cu-Nb nanocrystalline alloy powder.

[0070] Figures 6 to 9 show various modifications of the first embodiment of the present invention.

[0071] Referring to Figure 6, the first body 110 contacts the lower part of the coil 300. Specifically, the first body 110 contacts the coil insulating film IF. Referring to Figure 7, the first body 110 is formed up to a region higher than the lower surface of the coil 300. That is, at least a portion of the coil 300 is located within the first body 110.

[0072] There is a trade-off relationship between magnetostrictive properties and saturation current (Isat), and the entire lower region of the coil 300 can be formed as the first body 110 depending on the saturation current (Isat) characteristics required by the coil component 1000.

[0073] Referring to Figure 8, the third body 130 is positioned on one surface (bottom surface) of the first body 110. The third body 130 contains a third magnetic material and resin. The saturation magnetostriction constant of the first magnetic material 11 is smaller than the saturation magnetostriction constant of the third magnetic material.

[0074] The third body 130 contains magnetic particles with a relatively high saturation magnetostriction constant, similar to the second body 120 described above. The third body 130 is located below the first body 110 and is exposed on the fifth surface 105 of the body 100.

[0075] According to this modified example, magnetic particles with a relatively low saturation magnetostriction constant are arranged only in a portion of the lower part of the coil 300. That is, the first body 110 can be formed only in a portion of the body 100 where the magnetic flux density is concentrated, thereby effectively reducing the magnetostriction phenomenon.

[0076] The explanation regarding the third magnetic material is the same as the explanation regarding the second magnetic material 12, and a detailed explanation would be redundant, so it is omitted.

[0077] A modified example shown in Figure 9 will be explained after the description of the support member 200 and the coil 300.

[0078] The support member 200 is embedded within the main body 100 and supports the coil 300, which will be described later.

[0079] The support member 200 is formed from an insulating material comprising at least one of a thermosetting insulating resin such as epoxy resin, a thermoplastic insulating resin such as polyimide, and a photosensitive insulating resin, and is formed from an insulating material in which a reinforcing material such as glass fiber or inorganic filler is impregnated into such an insulating resin. For example, the support member 200 is formed from insulating materials such as copper-clad laminate (CCL), prepreg, ABF (Ajinomoto Build-up Film), FR-4, BT (Bismaleimide Triazine) resin, and PID (Photo Imageable Dielectric).

[0080] As inorganic fillers, at least one selected from the group consisting of silica (SiO2), alumina (Al2O3), silicon carbide (SiC), barium sulfate (BaSO4), talc, mud, mica powder, aluminum hydroxide (Al(OH)3), magnesium hydroxide (Mg(OH)2), calcium carbonate (CaCO3), magnesium carbonate (MgCO3), magnesium oxide (MgO), boron nitride (BN), aluminum borate (AlBO3), barium titanate (BaTiO3), and calcium zirconate (CaZrO3) can be used.

[0081] When the support member 200 is formed of an insulating material containing reinforcing material, the support member 200 can provide superior rigidity. When the support member 200 is formed of an insulating material that does not contain glass fibers, the support member 200 is advantageous for reducing the overall thickness of the coil 300. When the support member 200 is formed of an insulating material containing a photosensitive insulating resin, the number of processes is reduced, which is advantageous for reducing production costs, and it is possible to process micropores.

[0082] The coil 300 is placed inside the main body 100 and exhibits the characteristics of a coil component. For example, when the coil component 1000 of this embodiment is used as a power inductor, the coil 300 can stabilize the power supply of electronic equipment by storing the electric field in a magnetic field and maintaining the output voltage.

[0083] Referring to Figure 2, at least a portion of the coil 300 is located within the second region 120 of the main body 100. As described above, since the first main body 110 is formed only in the lower region of the coil 300, the coil 300 is not located within the first main body 110. However, it is not limited to this, and as shown in Figure 7, the coil 300 may be located across both the first main body 110 and the second main body 120.

[0084] The coil 300 is arranged on one surface of the support member 200 to form multiple turns. In this embodiment, the coil 300 includes a first coil pattern 310 arranged on one surface of the support member 200 facing the sixth surface 106 of the main body 100, a second coil pattern 320 arranged on the other surface of the support member 200, and vias 330 that penetrate the coil member 200 and connect the first coil pattern 310 and the second coil pattern 320. As a result, the coil 300 applied to this embodiment is formed as a single coil that generates a magnetic field in the third direction (Z direction) of the main body 100 with respect to the core.

[0085] Each of the first coil pattern 310 and the second coil pattern 320 is a planar helical shape that forms at least one turn around the core 110 of the main body 100. For example, with reference to the directions in Figures 1 and 2, the first coil pattern 310 forms multiple turns around the core on the upper surface of the support member 200. The second coil pattern 320 forms multiple turns around the core on the lower surface of the support member 200.

[0086] One end of the first coil pattern 310 extends to the first surface 101 of the main body and is connected to the first external electrode 400, which will be described later, and the other end is connected to the via 330. One end of the second coil pattern 320 extends to the second surface 102 of the main body and is connected to the second external electrode 500, which will be described later, and the other end is connected to the via 330.

[0087] At least one of the coil patterns (310, 320) and via 330 includes at least one conductive layer.

[0088] For example, when the first coil pattern 310 and via 330 are formed by plating, each of the first coil pattern 310 and via 330 includes a seed layer formed by electroless plating or vapor deposition such as sputtering, and an electroplated layer. Here, the electroplated layer is either a single-layer structure or a multilayer structure. A multilayer electroplated layer is formed in a conformal film structure in which one electroplated layer covers the other electroplated layer, and is formed in a shape in which the other electroplated layer is laminated on only one surface of the other electroplated layer. The seed layers of the first coil pattern 310 and via 330 are formed integrally without boundaries between them, but are not limited to this. The electroplated layers of the first coil pattern 310 and via 330 are formed integrally without boundaries between them, but are not limited to this.

[0089] Each of the coil patterns (310, 320) and vias 330 is formed from a conductive material such as, but is not limited to, copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), nickel (Ni), lead (Pb), titanium (Ti), molybdenum (Mo), or alloys thereof.

[0090] Referring to Figure 9, the thickness of the coil 300 in this modified example differs between the innermost turn and the outermost turn.

[0091] Specifically, in the first coil pattern 310, the innermost turn has a thickness smaller than the outer turn. If the coil 300 is deflected towards the top of the main body 100, the magnetic flux density may concentrate at the top of the coil component, potentially weakening the DC-bias characteristics. Therefore, by reducing the thickness of the innermost turn of the first coil pattern 310 where the magnetic flux concentrates, the magnetic flux passage area can be increased, thereby preventing the concentration of magnetic flux density at the top of the coil 300.

[0092] The first and second external electrodes (400, 500) are positioned on the first surface 101 and the second surface 102 of the main body 100, respectively. The first external electrode 400 is positioned on the first surface 101 of the main body 100 and connected to one end of the first coil pattern 310. The second external electrode 500 is positioned on the second surface 102 of the main body 100 and connected to one end of the second coil pattern 320.

[0093] The first and second external electrodes (400, 500) are formed in a single-layer or multi-layer structure. For example, the first external electrode 400 consists of a first layer containing copper (Cu), a second layer containing nickel (Ni) placed on the first layer, and a third layer containing tin (Sn) placed on the second layer. Here, the first to third layers are each formed by plating, but are not limited to this. As another example, the first external electrode 400 may include a resin electrode containing conductive powder such as silver (Ag) and resin, and a nickel (Ni) / tin (Sn) plating layer plated on the resin electrode.

[0094] The first and second external electrodes (400, 500) are formed from conductive materials such as copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), nickel (Ni), lead (Pb), titanium (Ti), or alloys thereof, but are not limited to these.

[0095] Referring to Figure 2, the insulating film IF is positioned along the surface of the coil 300.

[0096] The insulating film IF insulates the coil 300 from the main body 100. The insulating film IF covers the outer surface of the coil 300 and insulates the coil 300 from the main body 100. The insulating film IF is formed in the form of a conformal film along the outer surface of the coil 300.

[0097] The insulating film IF includes, but is not limited to, known insulating materials such as parylene. As another example, the insulating film IF may include an insulating material such as epoxy resin instead of parylene. The insulating film IF is formed by, but is not limited to, vapor deposition. As another example, the insulating film IF may be formed by laminating and curing insulating films for forming the insulating film IF on both sides of the support member 200 on which the coil 300 is formed, or by applying and curing insulating paste for forming the insulating film IF on both sides of the support member 200 on which the coil 300 is formed.

[0098] On the other hand, in the present invention, the insulating film IF is an optional configuration, and if the main body 100 can ensure sufficient electrical resistance under the operating conditions of the coil component 1000 according to this embodiment, the insulating film IF may be omitted.

[0099] The insulating layer 600 is placed on the surface of the main body 100 so that the main body 100 is not exposed to the outside of the coil components. Specifically, the insulating layer 600 is placed on the third, fourth, fifth, and sixth surfaces (103, 104, 105, 106) of the main body 100 in areas where external electrodes are not formed. The insulating layer 600 is placed on the surface of the main body 100 where external electrodes (400, 500) are not formed, and can electrically protect the coil components, reduce leakage current, and prevent plating bleeding when forming external electrodes.

[0100] The insulating layer 600 is made of thermoplastic resins such as polystyrene, vinyl acetate, polyester, polyethylene, polypropylene, polyamide, rubber, and acrylic; thermosetting resins such as phenol, epoxy, urethane, melamine, and alkyd; photosensitive resins; parylene; SiO2 x , or SiN x Includes.

[0101] ≪Second Embodiment≫ The coil component 2000 according to the second embodiment is a wound-type coil component. Hereinafter, only the parts of the wound-type coil component that differ from the coil component 1000 according to the first embodiment will be described. The remaining components can be described in the same way as in the first embodiment.

[0102] Figure 10 is a perspective view showing a coil component according to a second embodiment of the present invention, and Figure 11 is a schematic cross-sectional view showing a cross-section in the II-II' direction of Figure 10.

[0103] Referring to Figures 10 and 11, the shapes of the first and second bodies differ compared to the first embodiment.

[0104] The second body 120 is positioned on top of the first body 110 and surrounds the entire surface of the first body 110 except for its bottom surface. Therefore, the first, second, third, fourth, and sixth surfaces of the body 100 are formed by the second body 120, and the fifth surface 105 of the body 100 is formed by the first body 110.

[0105] The first body 110 supports the winding coil 300 and includes a core that penetrates at least a portion of the winding coil 300.

[0106] The second body 120 covers the first body 110 and the winding coil 300. The second body 120 is placed on the first body 110 and the winding coil 300, and then pressurized to bond to the first body 110.

[0107] The winding coil 300 is positioned on the upper surface of the first body 110 and is wound around the core. The winding coil 300 is formed by spirally winding a metal wire, such as a copper wire, whose surface is coated with an insulating film IF. As a result, each turn of the winding coil 300 has a form covered with the insulating film IF.

[0108] The winding coil 300 has both ends extending to the first surface 101 and the second surface 102 of the main body 100, respectively, and connected to the external electrodes (400, 500).

[0109] Referring to Figure 12, the first body 110 is formed to be smaller compared to Figure 11.

[0110] In this modified example, the molded portion of the wound coil component is formed in a double layer. The first body 110 is placed inside the molded portion, and the second body 120 is placed outside the molded portion.

[0111] The first body 110 does not come into contact with the winding coil 300.

[0112] The second body 120 is positioned on the outside of the molded part and on the cover part, and no boundary is formed between them.

[0113] ≪Third Embodiment≫ The coil component 3000 according to the third embodiment is a laminated coil component. Hereinafter, only the parts of the laminated coil component that differ from the coil component 1000 according to the first embodiment will be described. The remaining components can be described as described in the first embodiment.

[0114] Figure 13 is a perspective view showing a coil component according to a third embodiment of the present invention, and Figure 14 is a schematic cross-sectional view showing the cross-section in the III-III' direction of Figure 13.

[0115] Referring to Figure 13, the main body 100 is formed by stacking multiple magnetic sheets in a third direction (Z direction) to create a coil 300 on the multiple magnetic sheets.

[0116] The first body 110 is positioned below the coil 300 and has a configuration in which multiple magnetic sheets are stacked. Similarly, the second body 120 is positioned above the first body 110 and has a configuration in which multiple magnetic sheets are stacked.

[0117] In other words, the main body 100 of the coil component 3000 according to the third embodiment is formed by stacking a plurality of magnetic sheets containing a magnetic material in a third direction (Z direction) and then firing them. Conductor patterns are formed on one surface of the plurality of magnetic sheets, and the conductor patterns are electrically connected to each other via conductive vias formed on adjacent magnetic sheets to form a coil 300.

[0118] Conductor patterns are formed by, but are not limited to, thick-film printing, coating, vapor deposition, and sputtering of conductive paste onto a green sheet for forming magnetic sheets.

[0119] Conductive vias are formed by creating through-holes in the thickness direction of each sheet and then filling the through-holes with conductive paste or the like, but are not limited to this method.

[0120] Figures 15 and 16 show modified examples of the third embodiment of the present invention.

[0121] Referring to Figure 15, the first body 110 contacts the lower part of the coil 300. Depending on the saturation current (Isat) characteristics required by the coil component 3000, the entire lower region of the coil 300 can be formed as the first body 110.

[0122] Referring to Figure 16, the uppermost turn of coil 300 is narrower than the lower turn. If coil 300 is deflected upwards, magnetic flux density may concentrate at the top of the coil component, potentially weakening the DC-bias characteristics. Therefore, reducing the width of the uppermost turn of the coil where the magnetic flux is concentrated can prevent the concentration of magnetic flux density at the top of coil 300.

[0123] Although embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is not limited to the embodiments described above, and can be modified and implemented in various ways without departing from the technical spirit of the present invention. [Explanation of symbols]

[0124] 11, 12, 14 1st, 2nd, 4th magnetic substance 100 Main Unit 101, 102, 103, 104, 105, 106 1st to 6th sides 110, 120, 130 Main Units 1-3 200 Support Member 300 coils 310, 320 First and second coil patterns 330 Beer 400, 500 1st, 2nd external electrode 600 Insulating layer 1000, 2000, 3000 coil parts IF insulating film

Claims

1. A first body containing a first magnetic material, A second body, which is positioned on the upper surface of the first body and contains a second magnetic material, An insulating layer disposed on the upper surface of the second main body, The device comprises a coil, at least a portion of which is disposed within the second body and extending to the surface of the second body, A coil component characterized in that the saturation magnetostriction constant of the first magnetic material is smaller than the saturation magnetostriction constant of the second magnetic material.

2. The coil component according to claim 1, characterized in that the saturation magnetostriction constant of the first magnetic material has a negative value or a value of 1 ppm (parts per million) or less.

3. The coil component according to claim 1, characterized in that the first magnetic material contains first pure iron particles.

4. The second magnetic material contains second pure iron particles, The coil component according to claim 3, characterized in that the area ratio occupied by the first pure iron particles in the cross-section of the first body is greater than the area ratio occupied by the second pure iron particles in the second body.

5. The coil component according to claim 1, characterized in that the first magnetic material includes nanocrystalline and amorphous materials.

6. The first magnetic material comprises Fe and Si, The coil component according to claim 1, characterized in that the Si content in the first magnetic material is 6.5 wt% or more and 8 wt% or less.

7. The second magnetic material comprises Fe and Si, The coil component according to claim 6, characterized in that the Si content in the second magnetic material is less than 6.5 wt%.

8. The first body further includes a third body disposed on the lower surface of the first body and containing a third magnetic material, The coil component according to claim 1, characterized in that the saturation magnetostriction constant of the first magnetic material is smaller than the saturation magnetostriction constant of the third magnetic material.

9. The first body further comprises a fourth magnetic material, The coil component according to claim 1, characterized in that the saturation magnetostriction constant of the fourth magnetic material is greater than the saturation magnetostriction constant of the first magnetic material.

10. The coil component according to claim 1, characterized in that at least a portion of the coil is disposed within the first main body.

11. The coil component according to claim 1, characterized in that the distance from the upper surface of the coil to the upper surface of the second body is smaller than the distance from the lower surface of the coil to the lower surface of the first body.

12. The coil component according to claim 1, further comprising external electrodes that cover both sides of the first body and both sides of the second body and are connected to the coil.

13. A body comprising a first body and a second body disposed on the upper surface of the first body, and containing pure iron particles, An insulating layer is placed on the upper surface of the second main body, The device comprises a coil, at least a portion of which is disposed within the second body and extending to the surface of the second body, A coil component characterized in that the area ratio occupied by the pure iron particles in the cross-section of the first body is greater than the area ratio occupied by the pure iron particles in the cross-section of the second body.

14. The main body further includes a third main body disposed on the lower surface of the first main body, The coil component according to claim 13, characterized in that the area ratio occupied by the pure iron particles in the cross-section of the first body is greater than the area ratio occupied by the pure iron particles in the cross-section of the third body.

15. The coil component according to claim 13, characterized in that the first main body is located at the lower part of the coil.

16. The coil component according to claim 13, characterized in that the second body does not contain the pure iron particles.

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