Fe-based alloys and electronic components containing them

Abstract

Provided are an Fe-based alloy having a high saturation magnetic flux density and minimized losses as the coercive force decreases, and an electronic component using the same. 【Solution means】 One embodiment of the present invention is (Fe (1-x) Co x ), a Si b B c P d Nb e Cu f C g represented by the composition formula, where x, a, b, c, e, g satisfy the conditions of 10 ≤ x ≤ 20, 80.0 ≤ a ≤ 82.0, 0 ≤ b ≤ 4.0, 8.0 ≤ c ≤ 12.0, 0 ≤ d ≤ 4.0, 1.0 ≤ e ≤ 3.0, 0.5 ≤ f ≤ 1.0, 0 ≤ g ≤ 2.0, to provide an Fe-based alloy.

Description

[Technical Field]

[0001] This invention relates to Fe-based alloys and electronic components containing them. [Background technology]

[0002] In the fields of inductors, transformers, motor cores, and wireless power transmission devices, development is progressing on soft magnetic materials that offer miniaturization and improved high-frequency characteristics. In particular, when using power inductors in high-current regions, superposition characteristics often become a problem. In connection with this, to prevent low inductance, inductors are designed considering the number of coil turns, coil shape, cross-sectional area, magnetic path length, magnetic material particle shape, distance, and insulation. However, due to constraints on inductor shape, coil DC resistance, and inductance, it is preferable to improve the saturation magnetic flux density of the magnetic material. A higher saturation magnetic flux density allows for an increase in core shape and the number of coil turns in the magnetic core.

[0003] Furthermore, reducing core loss is also important in power inductors. Core loss is represented by the sum of hysteresis loss and eddy current loss, and in order to reduce hysteresis loss, it is important to lower the coercivity of the magnetic material. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] One of the objectives of the present invention is to provide an Fe-based alloy that has a high saturation magnetic flux density while minimizing losses as the coercivity decreases, and electronic components using the same. [Means for solving the problem]

[0005] As a method for solving the above-mentioned problems, one embodiment of the present invention is (Fe (1-x) Co x ) a Si b B c P d Nbe Cu f C g It is represented by the composition formula of, where x, a, b, c, e, g satisfy the conditions of 10 ≦ x ≦ 20, 80.0 ≦ a ≦ 82.0, 0 ≦ b ≦ 4.0, 8.0 ≦ c ≦ 12.0, 0 ≦ d ≦ 4.0, 1.0 ≦ e ≦ 3.0, 0.5 ≦ f ≦ 1.0, 0 ≦ g ≦ 2.0, and an Fe-based alloy is provided.

[0006] In one embodiment, it can include an amorphous phase and a crystalline phase.

[0007] In one embodiment, the crystalline phase may include at least one of Fe crystals and Fe-Co crystals.

[0008] In one embodiment, the content of the amorphous phase in the amorphous phase and the crystalline phase can be 90% or more.

[0009] In one embodiment, the crystalline phase may be present inside the amorphous phase.

[0010] In one embodiment, the average particle size of the crystalline phase can be 3 nm to 30 nm.

[0011] In one embodiment, b ≦ d in the composition formula.

[0012] Another aspect of the present invention includes a coil part and a main body that covers the coil part and contains a large number of magnetic particles. The magnetic particles are (Fe (1-x) Co x ) a Si b B c P d Nb e Cu f C g It is represented by the composition formula of, where x, a, b, c, e, g satisfy the conditions of 10 ≦ x ≦ 20, 79.0 ≦ a ≦ 82.0, 0 ≦ b ≦ 4.0, 8.0 ≦ c ≦ 12.0, 0 ≦ d ≦ 4.0, 1.0 ≦ e ≦ 3.0, 0.5 ≦ f ≦ 1.0, 0 ≦ g ≦ 2.0, and an electronic component containing an Fe-based alloy is provided. <able>

[0013] In one embodiment, the Fe-based alloy can include an amorphous phase and a crystalline phase.

[0014] In one embodiment, the crystalline phase may include at least one of Fe crystals and Fe-Co crystals.

[0015] In one embodiment, the content of the amorphous phase in the amorphous phase and the crystalline phase can be 90% or more.

[0016] In one embodiment, the crystalline phase may be present inside the amorphous phase.

[0017] In one embodiment, the average particle size of the crystalline phase can be 3 nm to 30 nm.

[0018] In one embodiment, b ≤ d may be satisfied in the above composition formula.

[0019] In one embodiment, it can further include a support substrate disposed in the main body to support the coil portion.

[0020] In one embodiment, the coil portion can include a wound-type coil.

Advantages of the Invention

[0021] According to one embodiment of the present invention, it is possible to realize an Fe-based alloy having a high saturation magnetic flux density and minimized loss as the coercive force decreases, and an electronic component using the same.

Brief Description of the Drawings

[0022] [Figure 1] It is a schematic perspective view showing a coil component according to one embodiment of the present invention. [Figure 2] It is a cross-sectional view taken along line I-I' of FIG. 1. [Figure 3] It shows an enlarged view of the main body region in the coil component of FIG. 2. [Figure 4] It shows an enlarged view of magnetic particles. [Figure 5] This is a schematic perspective view showing a coil component according to another embodiment of the present invention. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described below with reference to specific embodiments and accompanying drawings. However, embodiments of the present invention can be modified into several other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, embodiments of the present invention are provided to give a more complete explanation of the present invention to a person of the ordinary skill. Accordingly, the shapes and sizes of elements in the drawings may be enlarged or reduced (or highlighted or simplified) for a clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements.

[0024] Furthermore, in order to clearly illustrate the present invention in the drawings, parts unrelated to the explanation are omitted, the thickness is shown enlarged to clearly represent multiple layers and regions, and components with the same function within the scope of the same concept are described using the same reference numerals. Moreover, throughout the specification, when a part "includes" a certain component, unless otherwise stated to the contrary, it does not mean that other components are excluded, but rather that other components may be further included.

[0025] Electronic components The following describes an electronic component according to one embodiment of the present invention, with a coil component selected as a representative example. However, the Fe-based alloy described later can also be applied to other electronic components besides coil components, such as wireless charging devices and filters.

[0026] Figure 1 is a schematic perspective view showing the external shape of a coil component of one embodiment of the present invention. Figure 2 is a cross-sectional view taken along the line I-I' in Figure 1. Figure 3 is an enlarged view of the main body region of the coil component in Figure 2, and Figure 4 is an enlarged view of the magnetic particles. Figure 5 is a schematic perspective view showing a coil component according to another embodiment of the present invention.

[0027] First, referring to Figures 1 and 2, a coil component 100 according to one embodiment of the present invention mainly includes a main body 101, a support substrate 102, a coil pattern 103, and external electrodes 105 and 106, and the main body 101 includes a plurality of magnetic particles 111.

[0028] The main body 101 covers and protects the coil portion 103 and can contain a large number of magnetic particles 111, as shown in the configuration in Figure 3. Specifically, the magnetic particles 111 may be dispersed in an insulator 112 made of resin or the like. In this case, the magnetic particles 111 can be soft magnetic powder and may contain an Fe-based alloy. The specific composition of the Fe-based alloy contained in the magnetic particles 111 will be described later. When using an Fe-based alloy with the composition proposed in this embodiment, it is possible to maintain soft magnetic properties while having a high level of saturation magnetic flux density, and thus it can exhibit magnetic properties suitable for use in an inductor.

[0029] The support substrate 102 supports the coil portion 103 and can be formed from a polypropylene glycol (PPG) substrate, a ferrite substrate, or a metallic soft magnetic substrate. As shown in the figure, the central part of the support substrate 102 is perforated to form a through hole, and the main body 101 can be filled into such a through hole to form the magnetic core portion C.

[0030] The coil section 103 is installed inside the main body 101 and performs various functions within the electronic device through the characteristics emanating from the coil of the coil electronic component 100. For example, the coil electronic component 100 may be a power inductor, in which case the coil section 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 pattern forming the coil section 103 can be stacked on both sides of the support substrate 102 and electrically connected via conductive vias V that penetrate the support substrate 102. The coil section 103 can be formed in a spiral shape, and the outermost part of such a spiral shape may include a lead-out section L exposed to the outside of the main body 101 for electrical connection with external electrodes 105 and 106.

[0031] The coil portion 103 is arranged on at least one of the two opposing surfaces of the support substrate 102: the first surface (upper surface with reference to Figure 2) and the second surface (lower surface with reference to Figure 2). As in this embodiment, the coil portion 103 can be arranged on both the first and second surfaces of the support substrate 102, in which case the coil portion 103 can include the pad area P. However, in contrast, the coil portion 103 may be arranged on only one surface of the support substrate 102. On the other hand, the coil pattern forming the coil portion 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.

[0032] On the other hand, the coil portion may be provided in a form other than that shown in Figure 1. For example, the coil portion 203 may be realized as a wound type, as in the embodiment shown in Figure 5. In this case, a support substrate for supporting the coil portion 203 does not need to be arranged inside the main body 101. The coil portion 203 may be a wound coil formed by winding a metal wire such as a copper wire (Cu-wire) which includes a metal wire and a coating layer that covers the surface of the metal wire. Therefore, the entire surface of each of the multiple turns of the coil portion 203 can be covered with the coating layer. On the other hand, the metal wire may be a flat wire, but is not limited thereto. If the coil portion 203 is formed with a flat wire, the cross-section of each turn of the coil portion 203 can be rectangular. The coating layer may contain epoxy, polyimide, liquid crystal polymer, etc., alone or in combination, but is not limited thereto.

[0033] External electrodes 105 and 106 can be formed on the outside of the main body 101 and connected to the lead-out portion L. The external electrodes 105 and 106 may include a conductive paste layer formed using a paste containing a metal with excellent electrical conductivity, which may be a conductive paste containing, for example, nickel (Ni), copper (Cu), tin (Sn), or silver (Ag) individually or in alloys thereof. Furthermore, a plating layer (not shown) 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.

[0034] As described above, in this embodiment, the magnetic particles 111 include an Fe-based alloy that exhibits excellent magnetic properties during manufacturing in powder form. The characteristics of the Fe-based alloy that may be included in the magnetic particles 111 will be described in detail below. However, the Fe-based alloy described later can also be used in forms other than powder, such as thin metal sheets. Furthermore, such alloys can be used not only in inductors but also in transformers, motor cores, electromagnetic wave shielding sheets, and the like.

[0035] Fe alloy According to research by the inventors of this invention, in the case of the Fe-based alloy with the composition proposed in this embodiment, it was possible to maintain a low level of coercivity while exhibiting high amorphousness and excellent saturation magnetic flux density in the powder state. The reason why the coercivity can be maintained at a low level is thought to be that when the powder is manufactured by the atomization process, Fe or Fe-Co crystalline phases are precipitated in addition to the amorphous phase within the Fe-based alloy. In the case of such an Fe-based alloy, it is possible to realize a form in which the crystalline phase is partially precipitated within the amorphous phase in the powder state after atomization, without undergoing a heat treatment process for the precipitation of nanocrystalline grains.

[0036] Specifically, the above Fe alloy is (Fe (1-x) Co x ) a Si b B c P d Nb e Cu f C g The composition is expressed by the following formula, where x, a, b, c, e, and g satisfy the conditions 10≦x≦20, 79.0≦a≦82.0, 0≦b≦4.0, 8.0≦c≦12.0, 0≦d≦4.0, 1.0≦e≦3.0, 0.5≦f≦1.0, and 0≦g≦2.0. In the case of the above Fe-based alloy satisfying such a composition, a high level of saturation magnetic flux density can be achieved while maintaining a low level of coercivity. Furthermore, these properties can be maintained even if the material is manufactured from a highly amorphous powder and has not undergone a separate heat treatment process for nanocrystalline grain formation.

[0037] Referring to Figure 4, in the case of magnetic particles 111 containing an Fe-based alloy according to this embodiment, an amorphous phase 121 and a crystalline phase 122 may be included, where the crystalline phase 122 may include at least one of Fe crystals and Fe-Co crystals. The ratio of amorphous phase 121 to crystalline phase 122 can be adjusted so as to suppress an excessive increase in coercivity while maintaining a high level of saturation magnetic flux density. Therefore, in this embodiment, the content of amorphous phase 121 in the amorphous phase 121 and crystalline phase 122 is set to 90% or more. The relative content of amorphous phase 121 and crystalline phase 122 can be obtained through the volume they occupy within the magnetic particle 111 or the area they occupy in one cross-section of the magnetic particle 111. Here, when obtaining the relative content based on the area of ​​the cross-section, it can be obtained through the cross-sections of many magnetic particles 111 that appear in one cross-section of the main body 101, and in this case, many cross-sections of the main body 101 can be taken and an average value can be obtained. As shown in Figure 4, the crystalline phase 122 may exist inside the amorphous phase 121. The average particle size d of the crystalline phase 122 may be 3 nm to 30 nm, where the average particle size d may be the average of values ​​measured in one cross-section of the magnetic particle 111. Alternatively, the average particle size d can be obtained through the cross-sections of numerous magnetic particles 111 appearing in one cross-section of the main body 101. In this case, multiple cross-sections of the main body 101 can be taken to obtain an average value.

[0038] To further examine the method for measuring the particle sizes of the amorphous phase 121 and crystalline phase 122, first, the particle sizes of the amorphous phase 121 and crystalline phase 122 can be obtained from a cross-sectional image of the magnetic body 101, for example, from an image obtained from a cross-section of the magnetic body 101 cut midway in the second direction D2, using Figure 2 as a reference, in the first direction-third direction D1-D3, and this can be the average value for multiple magnetic particles 111. Furthermore, the particle sizes of the amorphous phase 121 and crystalline phase 122 may also be their respective major axis lengths. However, in some cases, the area of ​​the particle sizes of the amorphous phase 121 and crystalline phase 122 can be calculated in the cross-section of the magnetic body 101 and then converted to an equivalent diameter. Note that, since the magnetic particles 111 can be deformed in the outer region of the magnetic body 101 due to the compression process, etc., the particle size can be measured excluding the region corresponding to a length within 5% or 10% from the surface of the magnetic body 101. The grain sizes of the amorphous phase 121 and the crystalline phase 122 are not obtained from only one cross-section of the magnetic body 101, but may 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 and third directions D1-D3 (e.g., 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.

[0039] The main elements constituting the above Fe-based alloy will now be explained. First, Fe is the main element of Fe-based alloys and is an essential element responsible for magnetism. Similarly, Co is an element that partially replaces Fe to obtain a high saturation magnetic flux density. The Fe and Co content is preferably 80.0 to 82.0 mol% in the above Fe-based alloy. If the total of Fe and Co is 80 mol% or less, amorphous properties may improve and crystal precipitation may not occur. Conversely, if it is 82 mol% or more, the Fe and Co content is excessive, making it difficult to obtain a high level of amorphous phase, for example, soft magnetic powder with an amorphous phase of 90% or more. Furthermore, the ratio of Fe to Co is preferably set to 10% or more and 20% or less relative to Fe, that is, 10 ≤ x ≤ 20 in the above composition formula. When the amount of Co added is less than 10%, it is difficult to confirm an improvement in saturation magnetization properties, and when it exceeds 20%, amorphous properties improve, but the saturation magnetization properties tend to deteriorate.

[0040] In the case of Si, it is an element that affects amorphousness, thereby contributing to the reduction of core loss of magnetic particles. The Si content may be 0 to 4 mol% in the above Fe-based alloy (i.e., 0 ≤ b ≤ 4.0). In the case of B, it is an element that affects amorphousness, and in particular, it may be necessary for the formation of an amorphous phase at a high level of 90% or more in the above Fe-based alloy. The B content may be 8 to 12 mol% (i.e., 8.0 ≤ c ≤ 12.0) in terms of improving amorphousness and reducing core loss.

[0041] In the case of P, it is an element that affects amorphousness, and may be present in the above Fe-based alloy in an amount of 0 to 4 mol% (i.e., 0 ≤ d ≤ 4.0). In this case, the P content can be the same as or greater than the Si content. That is, in the above compositional formula, b ≤ d may be the case. If the P content exceeds 4 mol%, the amorphous phase becomes relatively larger, and the balance between Fe-based elements and amorphous-forming elements deteriorates, which may lead to a decrease in the saturation magnetic flux density.

[0042] Nb can prevent crystal coarsening after nanocrystal deposition in soft magnetic powders. By adjusting the Nb content, core loss can be controlled to the desired level while obtaining a high saturation magnetic flux density. The Nb content is preferably 1 to 3 mol% (i.e., 1.0 ≤ e ≤ 3.0). When the amount of Nb added is less than 1 mol%, the effect of preventing crystal coarsening tends to decrease, and when it exceeds 3 mol%, the crystal coarsening effect did not change significantly compared to when 3 mol% was added.

[0043] In the case of Cu, it is preferable to add it to the above Fe-based alloy in an amount of 0.5 to 1.0 mol% (i.e., 0.5 ≤ f ≤ 1.0). When Cu is less than 0.5 mol%, almost no crystal precipitation is obtained, while when it is 1 mol% or more, the amount of crystal precipitation tends to increase. In this respect, the Cu content can be determined as described above in order to obtain an amorphous phase at a level of 90% or more. C is the element responsible for the amorphous form and may be present in an amount of 0 mol% or more and 2.0 mol% or less (i.e., 0 ≤ g ≤ 2.0). When the C content is 2 mol% or less, the amorphousness of the Fe-based alloy can be improved. However, if C is added excessively, it may inhibit amorphousness and at the same time cause deterioration of soft porcelain properties.

[0044] This section describes trace amounts of other elements that may be present in Fe-based alloys, such as Al, Ti, S, N, and O. These other elements may be introduced during the raw material or manufacturing process and may affect the properties of Fe-based alloys. Therefore, it is preferable to control the content of these trace amounts of other elements. First, Al and Ti are trace elements that may be mixed into soft magnetic powders manufactured using industrial raw materials such as Fe-P and Fe-B. In this case, Al and Ti may reduce the proportion of the amorphous phase and the soft porcelain properties. Therefore, it is preferable to keep the content of Al and Ti below 0.05 mass% to avoid reducing the proportion of the amorphous phase, and more preferably below 0.005 mass% to improve the proportion of the amorphous phase and suppress the effect on the soft porcelain properties.

[0045] S may be mixed into soft magnetic powders manufactured using industrial raw materials such as Fe-P and Fe-B, and adding a small amount of S has the effect of promoting the spheroidization of the soft magnetic powder. However, if S is added excessively, it can lead to the organization of non-uniform nanocrystals and a decrease in soft porcelain properties. Therefore, to avoid a decrease in soft porcelain properties, the S content is preferably 0.5% by mass or less, and more preferably 0.05% by mass or less. N may originate from industrial raw materials or be mixed into the soft magnetic powder in the air during atomization or heat treatment. In this case, it may lead to a decrease in the proportion of amorphous phase, deterioration of filling properties during molding, and a decrease in soft porcelain properties. Therefore, to ensure a sufficient amorphous phase and suppress a decrease in soft porcelain properties, the N content is preferably 0.01% by mass or less, and more preferably 0.002% by mass or less. Oxygen (O) may originate from industrial raw materials or be mixed into the soft magnetic powder in the air during atomization or drying. In this case, it may lead to a decrease in the proportion of amorphous phase in the soft magnetic powder, deterioration of filling properties during molding, and a decrease in soft porcelain properties. Therefore, it is preferable to keep the oxygen (O) content at 1.0% by mass or less in order to suppress a decrease in the proportion of amorphous phase. Furthermore, it is more preferable to keep the oxygen (O) content at 0.3% by mass or less in order to suppress a decrease in the soft porcelain properties of the soft magnetic powder.

[0046] On the other hand, 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. 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 coil component 100, an electron beam accelerated to approximately 15-30 kV with an electron gun is struck against the surface of the magnetic particles 111. This generates X-rays with unique wavelengths (energies) for each component of the magnetic particles 111, and this method measures these X-rays with a detector to determine the chemical composition. 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 or the like. After this, the remaining magnetic particles 111 can be dissolved in an acidic solution, and their components can be analyzed using an inductively coupled plasma atomic emission spectrometer (ICP-AES). In addition, TEM-EDS (Transmission Electron Microscopy with Energy Dispersive Spectroscopy) analysis and SEM-EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) analysis can also be used. In the above-described analysis method, the cross-section of the magnetic component 100 can be used as a reference, with Figure 2 as the basis. 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 direction-third direction D1-D3, cut midway in the second direction D2 of the magnetic body 101, and this can be the average value for multiple magnetic particles 111. Alternatively, this analysis process can be performed on multiple cross-sections of the magnetic body 101, for example, multiple cross-sections in the first direction-third direction D1-D3 (e.g., five or more cross-sections) spaced equally apart in both directions from the midpoint of the second direction D2 of the magnetic body 101, and then the average value can be calculated.

[0047] The magnetic particles 111 according to this embodiment can be manufactured by various manufacturing methods. For example, in a powder manufacturing process using atomization methods such as water atomization or gas atomization to obtain magnetic particles 111, which are soft magnetic powders, first, raw materials are weighed to a predetermined composition and melted to produce a molten alloy. Then, the molten alloy is discharged from a nozzle and divided into alloy volumes using high-pressure gas or water, thereby producing fine soft magnetic powder. Furthermore, in such a powder manufacturing process, the shape and particle size of the soft magnetic powder can be adjusted by changing the manufacturing conditions. In this embodiment, the maximum particle size of the magnetic particles 111 may be 100 μm or less in order to improve the degree of amorphization. Also, if the particle size distribution of the magnetic particles 111 is too broad, it may cause unintended particle size segregation. Taking this into consideration, the maximum particle size of the magnetic particles 111 can be limited to 100 μm or less.

[0048] Furthermore, regarding the size of the magnetic particle 111, the D of the magnetic particle 111 50 The diameter can be approximately 20-40 μm. The diameter of the multiple magnetic particles 111 is obtained through an image obtained from a cross-section of one surface of the magnetic body 101, for example, a cross-section of the magnetic body 101 cut midway in the second direction D2 with respect to Figure 2, in the first direction-third direction D1-D3, and can be the average value for the multiple magnetic particles 111. Furthermore, the diameter of the multiple magnetic particles 111 may be the length of the long axis of the magnetic particle 111. On the other hand, if the magnetic particle 111 is not circular in the cross-section of the magnetic body 101, the area of ​​the magnetic particle 111 can be calculated and then converted to a circular equivalent diameter. In this case, since the magnetic particle 111 may be deformed in the outer region of the magnetic body 101 due to the crimping process, etc., the diameter can be measured excluding the region corresponding to a length within 5% or 10% from the surface of the magnetic body 101. On the other hand, the diameter of the multiple magnetic particles 111 is 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 and 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.

[0049] The inventors of this invention conducted experiments on the amorphous nature and magnetic properties (saturation magnetization, coercivity) of Fe-based alloys based on their composition, and the results are shown in Tables 1 to 4 below. Here, Table 1 shows the alloy composition, crystallinity (amorphous, crystalline, two-phase mixed), and degree of crystallinity of comparative examples, and Table 2 shows the saturation magnetization and coercivity of some comparative examples. Then, Table 3 shows the alloy composition, crystallinity, and degree of crystallinity of the examples, and Table 4 shows the saturation magnetization and coercivity of the examples. To evaluate the properties of Fe-based alloys, gas-atomized molten alloy was rapidly cooled with cooling water to produce soft magnetic powder with an average particle size of 25 μm, and this was used to fabricate magnetic cores for inductors. Then, the precipitated phase of the soft magnetic powder produced with the Fe-based alloy composition was evaluated by X-ray diffraction (XRD), and the percentage of anomalies was calculated. In this case, the average grain size and crystallinity of the crystalline phase could be calculated by analyzing the X-ray diffraction measurement results using the WPPD (Whole-powder-pattern decomposition method). Crystallinity was defined as the crystalline phase content, with the sum of the amorphous and crystalline phases being 100%. For magnetic properties, saturation magnetization (emu / g) and coercivity (Hc) were measured using a vibrating sample magnetometer (VSM).

[0050] [Table 1]

[0051] [Table 2]

[0052] [Table 3]

[0053] [Table 4]

[0054] The experimental results above show that in the case of comparative examples that do not satisfy the composition conditions of the Fe-based alloy according to the embodiment of the present invention, only amorphous or crystalline phases are present. Here, when the Fe-based alloy has only a crystalline phase, Fe-B alloy crystals that inhibit soft magnetic properties precipitate, which is a problem as it cannot be used as a soft magnetic material. Furthermore, it can be confirmed that in the example, compared to the case with only an amorphous phase in the comparative examples, a higher saturation magnetization value is achieved while maintaining a low level of coercivity. Specifically, when the Fe content exceeds 79 mol%, it becomes difficult to produce amorphous powder, and it is difficult to raise the saturation magnetization to a level of 168 emu / g or higher. In this embodiment, a portion of the Fe is replaced with Co to improve the amorphous properties. In addition, as the Fe or Fe-Co crystalline phase precipitates, the saturation magnetization can be significantly improved, the grain size of the crystalline phase is maintained finely, and good soft magnetic properties can be exhibited without a large change in coercivity.

[0055] The present invention is not limited by the embodiments described above and the accompanying drawings, but is limited by the claims provided. Therefore, within the scope of the technical idea of ​​the present invention as described in the claims, various forms of substitution, modification, and alteration are possible by persons with ordinary skill in the art, and these also fall within the scope of the present invention. [Explanation of symbols]

[0056] 100 coil components 101 Main Unit 102 Support substrate 103 Coil section 111 Magnetic particles 112 Insulator 105, 106 external electrode 121 Amorphous phase 122 Crystal phase C Core L Drawer section P Pad Area V conductive via

Claims

1. (Fe （１－ｘ） Co ｘ ) ａ Si ｂ B ｃ P ｄ Nb ｅ Cu ｆ C ｇ represented by the composition formula, where x, a, b, c, e, g satisfy the conditions of 10 ≤ x ≤ 20, 80.0 ≤ a ≤ 82.0, 0 ≤ b ≤ 4.0, 8.0 ≤ c ≤ 12.0, 0 ≤ d ≤ 4.0, 1.0 ≤ e ≤ 3.0, 0.5 ≤ f ≤ 1.0, 0 ≤ g ≤ 2.0, and is an Fe-based alloy.

2. The Fe-based alloy according to claim 1, comprising an amorphous phase and a crystalline phase.

3. The Fe-based alloy according to claim 2, wherein the crystalline phase comprises at least one of Fe crystals and Fe-Co crystals.

4. The Fe-based alloy according to claim 2, wherein the amorphous phase and the content of the amorphous phase in the crystalline phase are 90% or more.

5. The Fe-based alloy according to claim 2, wherein the crystalline phase is located inside the amorphous phase.

6. The Fe-based alloy according to claim 2, wherein the average grain size of the crystalline phase is 3 nm to 30 nm.

7. The Fe-based alloy according to any one of claims 1 to 6, wherein b ≤ d in the composition formula.

8. The coil section, The coil portion is covered by a main body containing numerous magnetic particles, and includes The magnetic particles are (Fe （１－ｘ） Co ｘ ) ａ Si ｂ B ｃ P ｄ Nb ｅ Cu ｆ C ｇ An electronic component comprising an Fe-based alloy represented by the compositional formula, where x, a, b, c, e, and g satisfy the following conditions: 10 ≤ x ≤ 20, 79.0 ≤ a ≤ 82.0, 0 ≤ b ≤ 4.0, 8.0 ≤ c ≤ 12.0, 0 ≤ d ≤ 4.0, 1.0 ≤ e ≤ 3.0, 0.5 ≤ f ≤ 1.0, and 0 ≤ g ≤ 2.

0.

9. The electronic component according to claim 8, wherein the Fe-based alloy includes an amorphous phase and a crystalline phase.

10. The electronic component according to claim 9, wherein the crystalline phase comprises at least one of Fe crystals and Fe-Co crystals.

11. The electronic component according to claim 9, wherein the amorphous phase and the content of the amorphous phase in the crystalline phase are 90% or more.

12. The electronic component according to claim 9, wherein the crystalline phase is located inside the amorphous phase.

13. The electronic component according to claim 9, wherein the average particle size of the crystalline phase is 3 nm to 30 nm.

14. The electronic component according to claim 8, wherein b ≤ d in the above compositional formula.

15. The electronic component according to claim 8, further comprising a support substrate disposed within the main body for supporting the coil portion.

16. The electronic component according to claim 8, wherein the coil portion includes a wound-type coil.

17. The system further includes external electrodes located outside the main body, The electronic component according to any one of claims 8 to 16, wherein the external electrode includes a conductive paste layer and a plating layer.

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