Magnetic components

Abstract

This invention provides magnetic components with improved properties by using magnetic particles whose composition and particle shape have been adjusted for Fe-based alloys. [Solution] The magnetic component includes a magnetic body 101, and the magnetic body contains a plurality of magnetic particles 110 (111, 112). At least a portion of the magnetic particles contain an Fe-based alloy, and the Fe-based alloy contains 79 mol% to 84 mol% of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P. Furthermore, in the cross-section of the magnetic body, when the length of the long axis of the magnetic particle is L1 and the length of the short axis is L2, the asphericity of the magnetic particle is defined as 1-L2 / L1, and the average asphericity of the plurality of magnetic particles is 0 to 0.1.

Description

Technical Field

[0001] The present invention relates to magnetic components.

Background Art

[0002] With the miniaturization and thinning of electronic devices such as digital TVs, mobile phones, and notebook computers, miniaturization and thinning are also required for magnetic components applied to such electronic devices. To meet such requirements, various forms of magnetic components are used. An example of a magnetic component is an inductor including a coil, and research and development on wound type or thin film type inductors are actively conducted.

[0003] The main issue associated with the miniaturization and thinning of magnetic components is to achieve the same characteristics as in the past despite such miniaturization and thinning. To meet such requirements, the proportion of the magnetic material in the core filled with the magnetic material must be increased. However, due to reasons such as the strength of the magnetic body and changes in frequency characteristics due to insulation, there is a limit to increasing that proportion.

[0004] As an example of manufacturing a magnetic component, a method is used in which a sheet obtained by mixing magnetic particles and resin or the like is laminated on a coil and then pressurized to realize a main body. Ferrites, metals, etc. can be used as such magnetic particles. When using metal magnetic particles, it is advantageous to increase the content of the particles in terms of the magnetic permeability characteristics of the magnetic component. However, in this case, the insulation of the magnetic body may deteriorate and eddy current loss may occur.

Summary of the Invention

Problems to be Solved by the Invention

[0005] One object of the present invention is to improve the characteristics of magnetic components by using magnetic particles in which the composition of the Fe-based alloy and the shape of the particles are adjusted.

Means for Solving the Problems

[0006] In relation to the above-mentioned problems, the present invention aims to propose a novel structure for magnetic components through one example. Specifically, one embodiment of the present invention provides a magnetic component including a magnetic body, wherein the magnetic body includes a plurality of magnetic particles, at least some of the plurality of magnetic particles include an Fe-based alloy, and the Fe-based alloy contains 79 mol% to 84 mol% or more of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P.

[0007] In one embodiment, when the length of the major axis of the magnetic particle in a cross-section of the magnetic body is L1 and the length of the minor axis is L2, the non-sphericity of the magnetic particle is defined as 1-L2 / L1, and the average non-sphericity of the plurality of magnetic particles can be 0 or more and 0.1 or less.

[0008] In one embodiment, the multiple magnetic particles containing the Fe-based alloy can have a diameter of 3 μm or more, based on the diameter measured in an image of a cross-section of the magnetic body.

[0009] In one embodiment, the average non-sphericity can be the average non-sphericity of magnetic particles with a diameter of 3 μm or more among the plurality of magnetic particles, based on the diameter measured in an image of one cross-section of the magnetic body.

[0010] In one embodiment, the plurality of magnetic particles may have an average non-sphericality of 0.05 or more and 0.1 or less.

[0011] In one embodiment, the transition element may further include Co.

[0012] In one embodiment, the transition element may contain more than 0 mol% and up to 30 mol% of Co.

[0013] In one embodiment, the transition element may contain 5 mol% to 25 mol% of Co.

[0014] In one embodiment, the Fe-based alloy can contain 4 mol% or more and 5 mol% or less of P.

[0015] In one embodiment, the Fe-based alloy can further contain B.

[0016] In one embodiment, the Fe-based alloy can contain 8 mol% or more and 15 mol% or less of B.

[0017] In one embodiment, the Fe-based alloy can further contain C.

[0018] In one embodiment, the Fe-based alloy can contain more than 0 mol% and 2 mol% or less of C.

[0019] In one embodiment, the Fe-based alloy can further contain Cu.

[0020] In one embodiment, the Fe-based alloy can contain more than 0 mol% and 1.5 mol% or less of Cu.

Advantages of the Invention

[0021] In the case of a magnetic component containing magnetic particles according to an example of the present invention, hysteresis loss characteristics and the like can be improved.

Brief Description of the Drawings

[0022] [Figure 1] It is a schematic perspective view showing a magnetic component according to an embodiment of the present invention. [Figure 2] It is a cross-sectional view of a region of the magnetic component of FIG. 1. [Figure 3] It is a cross-sectional view showing an enlarged region of the magnetic body in the magnetic component of FIG. 1. [Figure 4] It is a particle size graph showing the relationship between the diameter measured from an image of a cross-section of the magnetic body and the number of particles at that diameter. [Figure 5] It shows a method for calculating the non-sphericity of magnetic particles. [Figure 6]It is a schematic perspective view showing a magnetic component according to another embodiment of the present invention. [Figure 7] It is a schematic exploded perspective view of the magnetic component shown in FIG. 6.

Embodiments for Carrying out the Invention

[0023] 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. Also, the embodiments of the present invention are provided to more fully explain the present invention to ordinary technicians. Therefore, the shape and size of elements in the drawings may be exaggerated for a clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0024] Various types of electronic components are used in electronic devices, and various types of magnetic components can be appropriately used among such electronic components for the purpose of noise removal and the like. That is, in an electronic device, magnetic components can be used as a power inductor, a high-frequency inductor, a general bead, a GHz bead, a common mode filter, and the like.

[0025] FIG. 1 is a schematic perspective view showing a magnetic component according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a region of the magnetic component of FIG. 1. And FIG. 3 is a cross-sectional view showing an enlarged region of the magnetic body in the magnetic component of FIG. 1.

[0026] Referring to Figures 1 to 3, the magnetic component 100 according to this embodiment includes a magnetic body 101 containing a plurality of magnetic particles 110, where at least some of the magnetic particles 111 contain an Fe-based alloy. The Fe-based alloy contains 79 mol% to 84 mol% of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P. Such compositional conditions are suitable for the magnetic particles 111 to have a relatively low non-sphericity. When the non-sphericity is low, for example, when the average non-sphericity is 0 to 0.1, the magnetic particles 111 can have a shape that is close to spherical on average, and in this case, hysteresis loss is low and properties such as saturation magnetic flux density can be improved. In addition, the packing ratio of the magnetic particles 111 in the magnetic body 101 can also be improved. The main components constituting the magnetic component 100 of this embodiment will be described below.

[0027] The magnetic body 101 has the external appearance of the magnetic component 100, and a coil 103 and a support member 102 that supports it can be arranged inside. As shown in the embodiment in Figure 3, the magnetic particles 111 can be dispersed inside the insulating material 120. The insulating material 120 can contain a dispersant, a binder, etc., and can contain polymer components such as epoxy resin and polyimide. The magnetic body 101 can be formed in an overall hexahedral shape. As an example, the magnetic body 101 may be formed such that the magnetic component 100 according to this embodiment, on which the external electrodes 105 and 106 are formed, has a length of 2.5 mm, a width of 2.0 mm and a thickness of 1.0 mm, or a length of 2.0 mm, a width of 1.2 mm and a thickness of 0.65 mm, or a length of 1.6 mm, a width of 0.8 mm and a thickness of 0.8 mm, or a length of 1.0 mm, a width of 0.5 mm and a thickness of 0.5 mm, or a length of 0.8 mm, a width of 0.4 mm and a thickness of 0.65 mm, but is not limited thereto. On the other hand, the above values ​​are merely design values ​​that do not reflect process errors, etc., so values ​​within the range that can be recognized as process errors should be considered to fall within the scope of the present invention.

[0028] The length of the magnetic component 100 in the first direction D1 described above may represent the maximum value among the dimensions of multiple line segments parallel to the first direction D1, obtained by connecting the two outermost boundary lines of the magnetic component 100 facing the first direction D1 as shown in the cross-sectional photograph of the magnetic component 100 in the central part of the second direction D2, between the first direction D1 and the third direction D3. Alternatively, it may represent the minimum value among the dimensions of multiple line segments parallel to the first direction D1, obtained by connecting the two outermost boundary lines of the magnetic component 100 corresponding to the first direction D1 as shown in the cross-sectional photograph. Alternatively, it may represent the arithmetic mean of at least three or more dimensions among the dimensions of multiple line segments parallel to the first direction D1, obtained by connecting the two outermost boundary lines of the magnetic component 100 corresponding to the first direction D1 as shown in the cross-sectional photograph. Here, the multiple line segments parallel to the first direction D1 may be equally spaced in the third direction D3, but the scope of the present invention is not limited thereto.

[0029] The length of the magnetic component 100 in the second direction D2 described above may represent the maximum value among the dimensions of multiple line segments parallel to the second direction D2, obtained by connecting the two outermost boundary lines facing the second direction D2 of the magnetic component 100 as shown in the optical microscope or SEM (Scanning Electron Microscope) photograph of the cross-section of the magnetic component 100 in the central part of the third direction D3, between the first direction D1 and the second direction D2. Alternatively, it may represent the minimum value among the dimensions of multiple line segments parallel to the second direction D2, obtained by connecting the two outermost boundary lines corresponding to the second direction D2 of the magnetic component 100 as shown in the cross-sectional photograph. Alternatively, it may represent the arithmetic mean of at least three or more dimensions among the dimensions of multiple line segments parallel to the second direction D2, obtained by connecting the two outermost boundary lines corresponding to the second direction D2 of the magnetic component 100 as shown in the cross-sectional photograph. Here, the multiple line segments parallel to the second direction D2 may be equally spaced relative to each other in the first direction D1, but the scope of the present invention is not limited thereto.

[0030] The length of the magnetic component 100 in the third direction D3 described above may represent the maximum value among the dimensions of multiple line segments parallel to the third direction D3, obtained by connecting the two outermost boundary lines facing the third direction D3 of the magnetic component 100 shown in the cross-sectional photograph of the first direction D1-third direction D3 at the central part of the second direction D2 of the magnetic component 100, based on an optical microscope or SEM (Scanning Electron Microscope) photograph. Alternatively, it may represent the minimum value among the dimensions of multiple line segments parallel to the third direction D3, obtained by connecting the two outermost boundary lines corresponding to the third direction D3 of the magnetic component 100 shown in the cross-sectional photograph. Alternatively, it may represent the arithmetic mean of at least three or more dimensions among the dimensions of multiple line segments parallel to the third direction D3, obtained by connecting the two outermost boundary lines corresponding to the third direction D3 of the magnetic component 100 shown in the cross-sectional photograph. Here, the multiple line segments parallel to the third direction D3 may be equally spaced in the first direction D1, but the scope of the present invention is not limited thereto.

[0031] The lengths of the magnetic component 100 in the first to third directions (D1-D3) may also be measured using the micrometer measurement method. The micrometer measurement method involves setting a zero point with a Gage R&R (Repeatability and Reproducibility) micrometer, inserting the magnetic component 100 according to this embodiment between the tips of the micrometer, and rotating the measuring lever of the micrometer to perform the measurement. On the other hand, when measuring the length of the magnetic component 100 using the micrometer measurement method, the length of the magnetic component 100 may represent the value measured once, or it may represent the arithmetic mean of multiple measurements.

[0032] Furthermore, regarding an example of a manufacturing method, the magnetic body 101 can be formed by methods such as lamination and winding. Taking the lamination method as an example, a coil 103 is formed on a support member 102 using a method such as plating, and then a large number of unit laminates for manufacturing the magnetic body 101 are provided and laminated. Here, the unit laminate can be manufactured by mixing magnetic particles 110 with organic substances such as thermosetting resin, binder and solvent to produce a slurry, applying the slurry to a carrier film to a thickness of several tens of micrometers using the doctor blade method, and then drying it to produce a sheet. In this way, the unit laminate can be manufactured in a form in which magnetic particles are dispersed in a thermosetting resin such as epoxy resin or polyimide. Multiple of the above-described unit laminates can be formed and pressure-laminated on the upper and lower parts of the coil 103 to realize the magnetic body 101.

[0033] The support member 102 supports the coil 103 and can be made of polypropylene glycol (PPG), ferrite, or a metallic soft magnetic material. As shown in the illustrated form, the central part of the support member 102 is penetrated to form a through hole, and the magnetic body 101 can be filled into such a through hole to form a magnetic core C.

[0034] The coil 103 is located inside the main body 101 and can perform various functions within the electronic device. For example, the magnetic component 100 may be a power inductor, in which case the coil 103 can store electricity in the form of a magnetic field to maintain the output voltage and stabilize the power supply. In this case, the coil 103 may be stacked on both sides of the support member 102, and may be electrically connected via conductive vias V that penetrate the support member 102. The coil 103 can be formed in a spiral shape, and the outermost part of such a spiral shape may include lead-out portions T that are exposed to the outside of the magnetic body 101 for electrical connection with external electrodes 105 and 106.

[0035] The coil 103 is arranged on at least one of the two opposing surfaces of the support member 102: a first surface (upper surface with reference to Figure 2) and a second surface (lower surface with reference to Figure 2). As in this embodiment, a first coil 103a and a second coil 103b can be arranged on the first surface and the second surface of the support member 102, respectively, in which case the coil 103 may include a pad P. However, in a different case, the coil 103 may be arranged on only one surface of the support member 102. On the other hand, the coil pattern forming the coil 103 can be formed using plating processes used in the art, such as pattern plating, anisotropic plating, isotropic plating, etc., and a multilayer structure can also be formed using multiple of these processes.

[0036] External electrodes 105 and 106 are formed on the outside of the magnetic body 101 and can be formed to connect to the lead-out portion T. External electrodes 105 and 106 can be formed using a paste containing a metal with excellent electrical conductivity, for example, a conductive paste containing nickel (Ni), copper (Cu), tin (Sn), or silver (Ag) individually or as an alloy thereof. Furthermore, a plating layer can be formed on the external electrodes 105 and 106. In this case, the plating layer may contain one or more selected from the group consisting of nickel (Ni), copper (Cu), and tin (Sn), for example, a nickel (Ni) layer and a tin (Sn) layer may be formed sequentially. In Figure 1, the external electrodes 105 and 106 have a form that extends from one side surface of the magnetic body 101 to the top and bottom surfaces and the remaining side surface, but they can be realized in various other shapes, for example, they may have an L-shape.

[0037] This embodiment allows for the improvement of the properties of the magnetic component 100 by adjusting the composition and non-sphericity, i.e., the degree to which the magnetic particles 111 contained in the magnetic body 101 deviate from a spherical shape. Referring to Figure 3, as described above, the magnetic body 101 contains a plurality of magnetic particles 111 containing Fe-based alloy components. In addition, the magnetic body 101 also contains fine second magnetic particles 112 with relatively small diameters, and the second magnetic particles 112 can fill the spaces between the relatively large-diameter magnetic particles 111. In this case, the magnetic particles 111 will also be referred to as first magnetic particles 111 to distinguish them from the second magnetic particles 112. The diameter that distinguishes the first magnetic particles 111 from the second magnetic particles 112 may be, for example, 3 μm. That is, magnetic particles with a diameter of 3 μm or more can be classified as first magnetic particles 111, and magnetic particles with a diameter of less than 3 μm can be classified as second magnetic particles 112. The second magnetic particle 112 may have a different composition from the second magnetic particle 111, and may include, for example, pure iron. However, the second magnetic particle 112 may also contain the same Fe-based alloy components as the second magnetic particle 111. One or more insulating films can be formed on the surfaces of the first magnetic particle 111 and the second magnetic particle 112. In addition to the first magnetic particle 111 and the second magnetic particle 112, smaller particles, such as third magnetic particles with a diameter of 300 to 500 nm, may also be included.

[0038] In this embodiment, the Fe-based alloy contained in the magnetic particles 111 has the following compositional conditions: Fe-containing transition elements are present in an amount of 79 mol% to 84 mol%, Si is present in an amount of 0 mol% to less than 1 mol%, and P is present in an amount exceeding 2 mol% but not exceeding 6 mol%. As an additional compositional condition, the above Fe-based alloy may further contain Co as a transition element. In this case, when the total content of the transition elements is 100 mol%, the transition elements may contain Co in an amount exceeding 0 mol% but not exceeding 30 mol%. As a more restrictive condition, the transition elements may contain Co in an amount of 5 mol% to 25 mol%. Furthermore, as a more specific content condition for the element P, the above Fe-based alloy may contain P in an amount of 4 mol% to 5 mol%.

[0039] As in this embodiment, a high level of saturated magnetic flux density can be obtained by forming an Fe-based alloy with a transition element content of 79 mol% or more, including Fe. However, if the transition element content is high, the amorphous performance of the magnetic particles 111 may decrease, so the upper limit of the transition element content can be limited to 84 mol%. Also, if the amorphousness of the magnetic particles 111 is high, the sphericity tends to decrease, that is, the asphericity of the magnetic particles 111 tends to increase. In this embodiment, the content of P and Si in the Fe-based alloy is limited to the above range, thereby making it possible to lower the asphericity of the magnetic particles 111 to a low level, for example, an average asphericity of 0 or more and 0.1 or less. In order to uniformly lower the asphericity of the magnetic particles 111, it is preferable to lower the viscosity of the molten metal used to obtain the magnetic particles 111 during the atomization process, and for this reason, the content range of P and Si was set to the above conditions.

[0040] On the other hand, in addition to the compositional conditions described above, the Fe-based alloy may further contain the following elements. First, the Fe-based alloy may further contain B, in which case the Fe-based alloy may contain B in an amount of 8 mol% to 15 mol%. Also, the Fe-based alloy may further contain C, in which case the Fe-based alloy may contain C in an amount exceeding 0 mol% but not exceeding 2 mol%. Also, the Fe-based alloy may further contain Cu, in which case the Cu may contain Cu in an amount exceeding 0 mol% but not exceeding 1.5 mol%. Also, the Fe-based alloy may further contain Nb, in which case the Nb may contain Nb in an amount exceeding 0 mol% but not exceeding 2 mol%.

[0041] The analysis of the components constituting the above Fe-based alloy and the content of each component can be carried out in the following process. For example, it may be carried out in the following process. First, as a method for analyzing the composition of magnetic particles 111, there is the EPMA (Electron Probe Microanalyzer) method. After polishing the cross-section of the magnetic component 100, an electron beam accelerated to approximately 15-30 kV from an electron gun is struck onto the surface of the magnetic particles 111. This generates X-rays with unique wavelengths (energies) for each constituent element of the magnetic particles 111, and the chemical composition is determined by measuring these with a detector. In this case, since the area analyzed by EPMA is a localized area of ​​the magnetic particles 111, the average value can be used after analyzing multiple measurement points (for example, five or more measurement points) at equal intervals on the surface of the magnetic particles 111. Another analytical method is the ICP (Inductively Coupled Plasma) method, in which polymer components are removed from the electronic component using a liquid that can decompose polymer components, and then the coil is removed using physical methods. Subsequently, the remaining magnetic particles 111 can be dissolved in an acidic solution, and their composition can be analyzed using an inductively coupled plasma atomic emission spectrometer (ICP-AES). Other methods such as TEM-EDS (Transmission Electron Microscopy with Energy Dispersive Spectroscopy) and SEM-EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) can also be used. In the case of the analysis method described above, it can be performed using a cross-section of the magnetic component 100 with Figure 2 as the reference. For example, the composition of the Fe alloy contained in the magnetic particles 111 can be obtained through images obtained from cross-sections in the first-third direction (D1-D3) obtained by cutting the magnetic body 101 midway in the second direction D2, and this can be the average value for multiple magnetic particles 111. Furthermore, this analysis process can also be performed on multiple cross-sections of the magnetic body 101, for example, multiple cross-sections in the first-third directions (D1-D3) that are equally spaced in both directions from the middle of the second direction D2 of the magnetic body 101 (for example, five or more cross-sections), and then the average value can be calculated.

[0042] As described above, the average nonsphericity of the multiple magnetic particles 111 can be between 0 and 0.1, meaning that the multiple magnetic particles 111 have a shape that is close to spherical on average. As a more specific example, the average nonsphericity of the multiple magnetic particles 111 can be between 0.05 and 0.1. According to the inventors' research on the present invention, they have found that in the case of non-spherical particles, particularly release particles that deviate significantly from a spherical shape, the nonsphericity has a higher correlation with the properties of the magnetic particles 111 than the sphericity. In this case, the average nonsphericity of the multiple magnetic particles 111 can be measured by an image of a cross-section of the magnetic body 101. That is, in this embodiment, the diameter and nonsphericity of the magnetic particles 111 were measured by cross-sectional analysis of the magnetic body 101, which is not in powder form, and the relationship with the properties of the magnetic particles 111 was analyzed. Furthermore, in the case of relatively large magnetic particles 111, the correlation between non-sphericity and properties is high, so it is preferable to consider non-sphericity only for magnetic particles 111 that have a diameter of a certain size or larger in the cross-section of the magnetic body 101.

[0043] Figure 4 is a particle size graph showing the relationship between the diameter measured in a cross-sectional image of the magnetic body and the number of particles at that diameter. Here, the particle size graph can be represented on a linear scale or a logarithmic scale. Referring to Figure 4, in the case of multiple magnetic particles 111 containing an Fe-based alloy that satisfies the above conditions, the lower limit d1 of the diameter may be 3 μm or more, and the upper limit d2 of the diameter does not necessarily need to be specified, but may be at the level of several tens of μm. Also, particles with a diameter of less than 3 μm and relatively small in diameter can be defined as second magnetic particles 112. On the other hand, in the particle size graph of Figure 4, the first magnetic particles 111 and the second magnetic particles 112 each show a form with one peak, but each can also have more peaks. Also, although the particle size graphs of the first magnetic particles 111 and the second magnetic particles 112 are separated from each other, they can also be connected to each other.

[0044] Thus, based on the diameter measured in an image of one cross-section of the magnetic body 101, the multiple magnetic particles 111 containing the Fe-based alloy can have a diameter of 3 μm or more. Furthermore, based on the diameter measured in an image of one cross-section of the magnetic body 101, the average asphericity can be the average asphericity of the magnetic particles 111 with a diameter of 3 μm or more among the multiple magnetic particles 111. In other words, among all the magnetic particles 110 present in one cross-section of the magnetic body 101, the magnetic particles 111 with a diameter of 3 μm or more satisfy the above content and asphericity conditions.

[0045] Figure 5 illustrates a method for measuring the asphericity of magnetic particles 111. The major axis length L1 and minor axis length L2 of the magnetic particle 111 can be measured in a cross-sectional image obtained using a SEM, where the directions of L1 and L2 may be perpendicular to each other. From the L1 and L2 obtained in this way, the asphericity can be calculated using the formula (E) = 1 - (L2 / L1). In this case, the diameter and asphericity of multiple magnetic particles 111 can be obtained through an image obtained from a cross-section of one surface of the magnetic body 101, for example, from a cross-section in the first-third direction (D1-D3) obtained by cutting the magnetic body 101 midway in the second direction D2, using Figure 2 as a reference, and can be an average value for multiple magnetic particles 111. The diameter of multiple magnetic particles 111 may be the major axis length L1 of the magnetic particle 111. However, in some cases, the area of ​​the magnetic particle 111 may be calculated in the cross-section of the magnetic body 101 and then converted to a circular equivalent diameter. In this case, the outer region of the magnetic body 101 may be deformed by the crimping process, etc., so the diameter and asphericity can be measured excluding a region corresponding to a length within 5% or 10% of the surface of the magnetic body 101. The diameter and asphericity of multiple magnetic particles 111 are not obtained from only one cross-section of the magnetic body 101, but can also be calculated by averaging multiple values ​​obtained from multiple cross-sections. Here, the multiple cross-sections of the magnetic body 101 may be, for example, multiple cross-sections in the first direction-third direction (D1-D3) (for example, five or more cross-sections) that are spaced equally apart in both directions from the middle of the second direction D2 of the magnetic body 101.

[0046] The inventors of this invention manufactured samples of magnetic particles with different Fe-based alloy compositions and degrees of asphericity, and analyzed their amorphous properties and hysteresis loss characteristics. Here, the degree of asphericity of magnetic particles can be adjusted not only by the composition of the Fe-based alloy, but also by the spray pressure of the molten metal during the powder manufacturing process. For example, among the spraying conditions of the molten metal during powder manufacturing, the higher the spray pressure, the lower the degree of asphericity, and the powder can be formed to be closer to a spherical shape. Table 1 below shows the compositional conditions of the samples and expresses the mole percentage of each element. In the case of Co content, it is shown as the mole percentage relative to the entire Fe-based alloy, and the mole percentage within the transition element can be converted to the mole percentage relative to the total of other transition elements such as Fe. Table 2 shows the amorphous properties, degree of asphericity, and hysteresis loss. In this case, the degree of asphericity was measured via a cross-sectional image of the magnetic particle. The hysteresis loss was based on 1 MHz.

[0047] [Table 1]

[0048] [Table 2]

[0049] In the above experimental examples, #1 to #4, indicated by *, are comparative examples, while the remaining #5 to #14 correspond to examples. As can be seen from the experimental results, under the compositional conditions described above, namely, when the Fe-based alloy of the magnetic particles contains 79 mol% to 84 mol% of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P, the hysteresis loss is significantly lower than that of the comparative examples. In addition to the compositional conditions of the Fe-based alloy, it was found that there is a high correlation between the non-sphericity, based on the cross-section of the magnetic particles, and the hysteresis loss.

[0050] Other embodiments of the present invention will be described with reference to Figures 6 and 7. In the embodiments described above, a coil 103 and a support member 102 that supports it are arranged inside a magnetic body 101, whereas the embodiments in Figures 6 and 7 use a wound coil. Specifically, the magnetic component 200 includes a molded portion 250, a coil 230, and a cover portion 211. The magnetic body 212 has the external appearance of the magnetic component 200 and has the coil 230 embedded inside. The magnetic body 212 includes a molded portion 250 and a cover portion 260. The molded portion 250 may include a core 220. The magnetic body 212 can be formed in an overall hexahedral shape. The magnetic body 212 includes a first face 201 and a second face 202 facing each other in a first direction D1, a third face 203 and a fourth face 204 facing each other in a second direction D2, and a fifth face 205 and a sixth face 206 facing in a third direction D3. Each of the third to sixth surfaces (203-206) of the magnetic body 212 corresponds to a wall surface of the magnetic body 212 that connects the first surface 201 and the second surface 202 of the magnetic body 212.

[0051] The magnetic body 212 can be realized in the same manner as in the embodiments described above. That is, the magnetic body 212 contains a plurality of magnetic particles, where at least some of the magnetic particles contain an Fe-based alloy. The Fe-based alloy contains 79 mol% to 84 mol% of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P. In addition to this, the magnetic particles contained in the magnetic body 212 can satisfy the non-sphericality conditions and specific composition conditions described above.

[0052] The magnetic body 212 may, for example, be formed such that the magnetic component 200 has a length of 2.0 mm, a width of 1.2 mm, and a thickness of 0.6 mm, but is not limited thereto. On the other hand, the magnetic body 212 includes a molded portion 250 and a cover portion 260, the cover portion 260 being positioned on top of the molded portion 250 and surrounding all surfaces of the molded portion 250 except the bottom surface. The molded portion 250 has one face and the other face opposite each other. The face of the molded portion 250 is the face corresponding to the bottom surface of the molded portion 250, and a receiving groove for accommodating both ends of the coil 230 can be formed thereon. The molded portion 250 includes a support portion 210 and a core 220. The core 220 is positioned in the center of the other face of the support portion 210 in a manner that penetrates the coil 230. The molded portion 250 can be formed by filling a mold with a composite material containing magnetic particles 111 and insulating resin. Here, the insulating resin may include, but is not limited to, epoxy, polyimide, liquid crystal polymer, etc., either alone or in combination.

[0053] The coil 230 is embedded in the magnetic body 212 and exhibits the properties of the magnetic component 200. For example, when the magnetic component 200 of this embodiment is used as a power inductor, the coil 230 can stabilize the power supply of electronic equipment by accumulating the electric field in the magnetic field and maintaining the output voltage. The coil 230 is arranged on the other side of the molded portion 250. Specifically, the coil 230 is wound around the core 220 and is arranged on the other side of the support portion 210. The coil 230 is an air-core coil and can be made up of a flat rectangular coil. The coil 230 can be formed by spirally winding a metal wire, such as a copper wire, whose surface is coated with an insulating material. The coil 230 can be made up of multiple layers. Each layer of the coil 230 is formed in a planar helical shape and can have multiple turns.

[0054] The cover portion 260 can be placed on the mold portion 250 and the coil 230. The cover portion 260 covers the mold portion 250 and the coil 230. After being placed on the support portion 210 of the mold portion 250, the core 220 and the coil 230, the cover portion 260 can be pressurized and bonded to the mold portion 250. The mold portion 250 and the cover portion 260 each contain magnetic particles 111, where the magnetic particles 111 may include a first layer 112 and a second layer 113 formed on the surface as described above.

[0055] Since the magnetic body 212 is a region including the molded portion 250 and the cover portion 260, one surface of the magnetic body 212 means one surface of the region including the molded portion 250 and the cover portion 260. The coil 230 includes a first lead portion and a second lead portion that are drawn out to the outside and positioned on the lower surface of the molded portion 250.

[0056] For example, the through grooves H1 and H2 may be formed by a mold when forming the molded portion 250. The mold for forming the molded portion 250 has protrusions corresponding to the through grooves H1 and H2, and the through grooves H1 and H2 can be formed in the molded portion 250 which is manufactured in a shape corresponding to the shape of the mold. Then, both ends of the coil portion 300 which is positioned to protrude from one surface of the molded portion 250 via the through grooves H1 and H2 of the molded portion 250 can be embedded inside the molded portion 250 in the magnetic sheet crimping process. This makes it possible to form a housing groove on one surface of the molded portion 250.

[0057] Both ends of the coil 230 may each penetrate one surface of the molded portion 250 and be positioned on the lower surface of the molded portion 250, for example, in the housing groove of the molded portion 250. Both ends of the coil 230 can be exposed to one surface of the molded portion 250, i.e., the second surface 202 of the magnetic body 212.

[0058] On the other hand, the magnetic component 200 according to this embodiment may further include an insulating layer 290 surrounding the surface of the coil 230. There are no restrictions on the method of forming the insulating layer 290, but for example, it can be formed by chemical vapor deposition of parylene resin or the like on the surface of the coil 230, or by known methods such as screen printing, exposure and development of photoresist (PR), spray coating, and dipping. The insulating layer 290 is not particularly limited as long as it can be formed as a thin film, but for example, it can be formed by including photoresist (PR), epoxy resin, etc.

[0059] The present invention is not limited by the embodiments described above or the accompanying drawings, but is limited by the claims provided. Accordingly, various forms of substitution, modification, and alteration are possible by persons with ordinary skill in the art, without departing from the technical idea of ​​the present invention as described in the claims, and these also fall within the scope of the present invention. [Explanation of symbols]

[0060] 100: Magnetic components 101: Magnetic body 102: Support member 103: Coil 111, 112: Magnetic particles 120: Insulating material C: Core Section L: Drawer part P: Pad V: Conductive via

Claims

1. A magnetic component including a magnetic body, The magnetic body includes a plurality of magnetic particles, At least some of the aforementioned plurality of magnetic particles contain an Fe-based alloy. The Fe-based alloy is a magnetic component containing 79 mol% to 84 mol% of transition elements including Fe, 0 mol% to less than 1 mol% of Si, and more than 2 mol% but 6 mol% or less of P.

2. In a cross-section of the magnetic body, when the length of the major axis of the magnetic particle is L1 and the length of the minor axis is L2, the non-sphericity of the magnetic particle is defined as 1 - L2 / L1. The magnetic component according to claim 1, wherein the plurality of magnetic particles have an average non-sphericality of 0 or more and 0.1 or less.

3. The magnetic component according to claim 2, wherein, based on the diameter measured in an image of one cross-section of the magnetic body, the plurality of magnetic particles including the Fe-based alloy have a diameter of 3 μm or more.

4. The magnetic component according to claim 2, wherein the average non-sphericity is the average non-sphericity of magnetic particles with a diameter of 3 μm or more among the plurality of magnetic particles, based on the diameter measured in an image of one cross-section of the magnetic body.

5. The magnetic component according to claim 1, wherein the plurality of magnetic particles have an average non-sphericality of 0.05 or more and 0.1 or less.

6. The magnetic component according to any one of claims 1 to 5, wherein the transition element further comprises Co.

7. The magnetic component according to claim 6, wherein the transition element contains more than 0 mol% and up to 30 mol% of Co.

8. The magnetic component according to claim 6, wherein the transition element contains 5 mol% to 25 mol% of Co.

9. The Fe-based alloy contains 4 mol% to 5 mol% of P, as described in any one of claims 1 to 5.

10. The magnetic component according to any one of claims 1 to 5, wherein the Fe-based alloy further comprises B.

11. The magnetic component according to claim 10, wherein the Fe-based alloy contains 8 mol% to 15 mol% of B.

12. The magnetic component according to any one of claims 1 to 5, wherein the Fe-based alloy further comprises C.

13. The magnetic component according to claim 12, wherein the Fe-based alloy contains more than 0 mol% and 2 mol% or less of C.

14. The magnetic component according to any one of claims 1 to 5, wherein the Fe-based alloy further comprises Cu.

15. The magnetic component according to claim 14, wherein the Fe-based alloy contains Cu in an amount greater than 0 mol% and less than or equal to 1.5 mol%.

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