Magnetic element of a power inductor and method of manufacturing the same

Abstract

A magnetic element suitable for a power inductor includes a magnetic body containing amorphous magnetic powder and / or nanocrystalline magnetic powder and at least one non-silicon glass material distributed between the amorphous magnetic powder and / or nanocrystalline magnetic powder; a coil embedded in the magnetic body; and a pair of electrodes electrically connected to two terminals of the coil, respectively.

Description

Technical Field

[0001] This invention relates to a magnetic element, and more particularly to a magnetic element suitable for power inductors. This invention also relates to a method for manufacturing a magnetic element suitable for power inductors. Background Technology

[0002] In recent years, as portable information electronic products and mobile communication products have developed towards thinner, lighter, smaller, and more multifunctional designs, functions with different voltage requirements, such as LCD screens, wireless communication modules, baseband modules, and camera modules, have been added to these products. This has expanded the voltage range that batteries need to provide. Consequently, the demand for conversion circuits or DC-DC converters that convert battery voltage to the voltage required by these functional components has also increased. This has also made the application of multilayer or combined power inductors, which affect power conversion efficiency, increasingly important.

[0003] Multilayer power inductors are known to be made of a magnetic material. During a high-temperature sintering process above 700°C, oxides are formed on the surface of the magnetic powder, and the magnetic powder adheres together through diffusion. Because the powder typically accumulates very densely, the particles are tightly bonded together, preventing the oxides from being evenly distributed across all powder surfaces. Therefore, the improvement in the insulation resistance of multilayer power inductors is limited. Furthermore, the crystallinity of the magnetic powder may change during the high-temperature sintering process, potentially leading to poor inductor characteristics.

[0004] Generally, multilayer or composite power inductors made from sintered magnetic powders have moderate permeability. However, the iron loss of sintered magnetic powders is relatively high, which may reduce the conversion efficiency of switching circuits or DC-DC converters. Furthermore, in order to utilize grain boundary diffusion to bond the magnetic powders together and achieve a high density, sintering temperatures need to be as high as 700°C or higher, which alters the crystalline state of the magnetic powder and results in less desirable inductance characteristics. Summary of the Invention

[0005] Therefore, the present invention provides a magnetic element suitable for power inductors, which can be formed at a relatively low co-firing temperature, while having low iron loss and good insulation resistance and inductance, and has better co-firing effect.

[0006] This invention also provides a method for manufacturing a magnetic element suitable for power inductors or single-layer power inductors. The manufacturing method of this invention involves a co-firing temperature below 500°C, resulting in a magnetic element with lower iron loss, good insulation resistance and inductance, and improved co-firing performance.

[0007] In one aspect of the present invention, a magnetic element suitable for power inductors or single-layer power inductors is provided.

[0008] In one embodiment, the amorphous magnetic powder and / or nanocrystalline magnetic powder has a first diameter distribution peak at at least a first diameter, and a second diameter distribution peak at a second diameter larger than the first diameter.

[0009] In one embodiment, the first diameter is 1-2 μm, and the second diameter is 10-20 times the first diameter.

[0010] In one embodiment, the amorphous magnetic powder and / or nanocrystalline magnetic powder has an average particle size D of 1–5 μm. 50 .

[0011] In one embodiment, the coil includes a plurality of wiring layers embedded in a first portion of the magnetic body and a plurality of via layers embedded in a second portion of the magnetic body, and the first portion and the second portion of the magnetic body differ in at least one parameter.

[0012] In one embodiment, the average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the first portion of the magnetic body is... 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the second part of the magnetic body is greater than that of the magnetic body. 50 .

[0013] In one embodiment, the first portion of the magnetic body includes at least one first magnetic layer in which one of the plurality of wiring layers is embedded, and the second portion of the magnetic body includes at least one second magnetic layer in which one of the plurality of via layers is embedded, and the thickness of the at least one first magnetic layer is greater than the thickness of the at least one second magnetic layer.

[0014] In one embodiment, the thickness of the second magnetic layer of the at least one second magnetic layer is less than 10 μm, while the thickness of the first magnetic layer of the at least one first magnetic layer is 20-40 μm.

[0015] In one embodiment, the magnetic body comprises at least two different materials: amorphous magnetic powder and / or nanocrystalline magnetic powder.

[0016] In one embodiment, the magnetic body further includes an insulating oxide powder with an average particle size D. 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder is smaller than that of the amorphous magnetic powder and / or nanocrystalline magnetic powder. 50 1 / 10 of.

[0017] In one embodiment, the average particle size D of the insulating oxide powder 50 Less than 0.1 μm.

[0018] In one embodiment, the magnetic body further includes an insulating oxide powder, which is formed by oxidizing a material selected from magnesium, titanium, zinc, silicon and aluminum.

[0019] In one embodiment, the magnetic body further includes an insulating oxide powder, which accounts for approximately 2.5 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the magnetic body.

[0020] In one embodiment, the amorphous magnetic powder and / or nanocrystalline magnetic powder includes an oxide of a material of the amorphous magnetic powder and / or nanocrystalline magnetic powder.

[0021] In one embodiment, the amorphous magnetic powder and / or nanocrystalline magnetic powder comprises an alloy comprising the elements Fe, Cr, Si, B, and C.

[0022] In one embodiment, the silicon-free glass material accounts for approximately 8 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the magnetic body.

[0023] In one embodiment, the silicon-free glass material includes a SnO-P2O5, V2O5-TeO2, Bi2O3-B2O3, ZnO, or A2O-MoO3 system, wherein A is an alkali metal or silver. A magnetic body is formed comprising amorphous magnetic powder and / or nanocrystalline magnetic powder and at least one silicon-free glass material distributed between the amorphous magnetic powder and / or nanocrystalline magnetic powder; a coil is formed and embedded within the magnetic body; and a pair of electrodes are formed and electrically connected to the two terminals of the coil, respectively. Attached Figure Description

[0024] After reading the following detailed description and accompanying drawings, those skilled in the art will more readily understand the present invention, wherein:

[0025] Figure 1A This is a schematic diagram of an embodiment of the magnetic element of the present invention.

[0026] Figure 1B This is a cross-sectional schematic diagram of the magnetic body included in one embodiment of the magnetic element of the present invention.

[0027] Figure 1C This is a cross-sectional schematic diagram of the magnetic body included in another embodiment of the magnetic element of the present invention.

[0028] Figure 2A For along Figure 1A A schematic cross-sectional view taken along line A-A' shows a coil included in one embodiment of the magnetic element of the present invention and embedded within the magnetic body of the magnetic element.

[0029] Figure 2BTo include Figure 2A A top view of each layer in the coil shown.

[0030] Figure 2C For the along Figure 2B A schematic diagram of the cross-section taken by line B-B', showing... Figure 2B One of the layers shown.

[0031] Figure 3 This is an illustrative diagram showing the particle size distribution of amorphous magnetic powder and / or nanocrystalline magnetic powder in a magnetic body included in one embodiment of the magnetic element of the present invention.

[0032] Figure 4 This is a schematic diagram illustrating the formation of a magnetic body included in one embodiment of the magnetic element of the present invention.

[0033] Figure 5 This is a schematic diagram of at least a portion of the surface region of a mechanically fused medium powder to an amorphous magnetic powder and / or a nanocrystalline magnetic powder, according to an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram illustrating the formation of a magnetic body included in another embodiment of the magnetic element of the present invention.

[0035] Figure 7 This is a schematic diagram illustrating the formation of a magnetic body included in another embodiment of the magnetic element of the present invention.

[0036] Figure 8 This is a schematic diagram illustrating the formation of a magnetic body in another embodiment of the magnetic element included in the present invention.

[0037] Figure 9 This is a schematic diagram of another embodiment of the magnetic element of the present invention.

[0038] The attached figures are labeled as follows:

[0039] 1: Magnetic body

[0040] 2: Coil

[0041] 3: Electrode

[0042] 10: Female operculum

[0043] 11: The first part of the magnetic body

[0044] 12: The second part of the magnetic body

[0045] 15,16: Magnetic body material

[0046] 20:Terminal

[0047] 21: Wiring layer

[0048] 22: Through-hole layer

[0049] 101, 131, 133, 135, 136: Amorphous magnetic powder and / or nanocrystalline magnetic powder

[0050] 102: Silicon-free glass material

[0051] 103: Oxide Materials

[0052] 111: Wiring Pattern Layer

[0053] 112: Interval Pattern Layer

[0054] 132: Medium powder

[0055] 134: Insulating oxide powder

[0056] D1: First diameter

[0057] D2: Second diameter Detailed Implementation

[0058] The present invention will be described in more detail with reference to the following embodiments. It should be noted that the following description of preferred embodiments of the present invention is for illustrative purposes only and is not intended to be an exhaustive description or to limit the precise forms disclosed.

[0059] Please see Figure 1A This is a schematic diagram of an embodiment of the magnetic element of the present invention. The magnetic element is suitable for use in a multilayer power inductor and includes a magnetic body 1, a coil 2, and a pair of electrodes 3. It should be noted that... Figure 1A The following describes an embodiment of the magnetic element of the present invention using a multilayer magnetic body 1 as an example; however, the present invention is not limited thereto, and the magnetic element of the present invention may also include, for example, a multilayer magnetic body 1. Figure 9 The non-multilayer magnetic body is shown. Additionally, in Figure 1A In the diagram, the magnetic body 1 is shown in a transparent manner to facilitate observation of the coil 2's layout, but the coil 2 is actually embedded within the multi-layered magnetic body 1. The magnetic body 1 includes amorphous magnetic powder and / or nanocrystalline magnetic powder 101 and at least one glass material 102 distributed within the amorphous magnetic powder and / or nanocrystalline magnetic powder 101 to bond the amorphous magnetic powder and / or nanocrystalline magnetic powder 101 together, such as... Figure 1B As shown. In one embodiment, the amorphous magnetic powder and / or nanocrystalline magnetic powder 101 includes, for example, iron powder formed of an alloy containing at least Fe, Cr, Si, B, and C elements. In another embodiment, the iron powder contained in the amorphous magnetic powder and / or nanocrystalline magnetic powder 101 has an oxide material 103 formed on at least a portion of its surface, such as... Figure 1C As shown.

[0060] To achieve the desired co-firing effect of magnetic components at low temperatures, the glass material 102 in embodiments of the present invention preferably comprises a silicon-free glass material. Examples of such silicon-free glass materials include, but are not limited to, SnO-P2O5, V2O5-TeO2, Bi2O3-B2O3, ZnO, or A2O-MoO3 systems, wherein A is an alkali metal or silver. Preferred examples of silicon-free glass materials are SnO-P2O5, V2O5-TeO2, Bi2O3-B2O3, or A2O-MoO3 systems. This silicon-free glass material includes an average particle size D. 50 The glass powder has a particle size of less than 1 μm. The softening point of this silicon-free glass material is approximately 300°C to 430°C. For example, the softening point of the SnO-P₂O₅ system is approximately 340°C to 400°C; the softening point of the V₂O₅-TeO₂ system is approximately 320°C to 350°C; and the softening point of the Bi₂O₃-B₂O₃ or ZnO system is approximately 400°C to 430°C. In the presence of this silicon-free glass powder, the diffusion of amorphous magnetic powder and / or nanocrystalline magnetic powder is avoided, as is the grain growth of amorphous magnetic powder and / or nanocrystalline magnetic powder, i.e., the transformation from the amorphous phase to the crystalline phase is avoided. The silicon-free glass material 102 in the magnetic body 1 is approximately 8 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder 101 in the magnetic body 1, allowing the gaps between the amorphous magnetic powder and / or nanocrystalline magnetic powder to be reduced as desired. Therefore, the magnetic flux density and inductance of the power inductor can be maintained.

[0061] Figure 2A For the along Figure 1A A schematic cross-sectional view taken along line A-A' shows a portion of the layers within the magnetic body 1. Figure 2A The example illustrates a coil included in one embodiment of the magnetic element of the present invention. For example... Figure 2A As illustrated, coil 2 is embedded in a multi-layered magnetic body 1, and electrodes 3 are electrically connected to the two terminals 20 of coil 2. As shown, coil 2 includes multiple wiring layers 21 interconnected through multiple through-hole layers 22. The wiring layers 21 are embedded in a first portion 11 of the magnetic body 1, while the through-hole layers 22 are embedded in a second portion 12 of the magnetic body 1. The magnetic body 1 and coil 2 are disposed between upper and lower magnetic covers 10. Please refer to... Figure 2B It shows Figure 2A The diagram shows an unfolded top view of the four wiring layers 21 of the coil 2. Each wiring layer 21 includes a conductive pattern formed of a conductive material, such as atomized silver, and each via layer 22 includes a via pattern formed of a conductive material. The conductive material of the via pattern is preferably, but not limited to, the same material, such as atomized silver, but can also be any other suitable material.

[0062] In this embodiment, the first portion 11 of the magnetic body 1 is a multilayer structure containing multiple first magnetic layers. Multiple wiring layers are embedded in the first portion 11. The first magnetic layer is defined as the wiring pattern layer 111 of the coil 2. On the other hand, the second portion 12 of the magnetic body 1 is a multilayer structure containing multiple second magnetic layers. Multiple via layers are embedded in the second portion 12. The second magnetic layer is defined as the spacing pattern layer 112 between the wiring pattern layers 111. (The last sentence appears to be incomplete and possibly refers to a different embodiment.) Figure 2B The B-B' line is taken Figure 2C As shown in the partial cross-sectional view, the wiring pattern layer 111 and the spacer pattern layer 112 can have different compositions, particle size distributions, layer thicknesses, or other required parameters. It should be noted that not all parameters need to be different; only some may differ. Examples are given below.

[0063] For example, in some embodiments, the amorphous magnetic powder and / or nanocrystalline magnetic powder contained in the wiring pattern layer 111 have at least one first diameter distribution peak at a first diameter D1, and at least one second diameter distribution peak at a second diameter D2 that is larger than the first diameter D1. Figure 3 As shown. In one embodiment, the first diameter D1 is approximately 1-2 μm, while the second diameter D2 is approximately 10-20 times the first diameter D1, to balance structural strength and insulation performance. If the powder is not large enough, larger powder will result in poorer strength after co-firing; if the powder is too large, larger powder will result in poorer insulation resistance. Additionally, smaller powder helps improve weather resistance. Powders of different sizes can be derived from different types of amorphous magnetic powders and / or nanocrystalline magnetic powders, such as D... 50 =29μm Fe-Si-BC-Cr alloy, D 50 =16μm Fe-Si-BC-Cr alloy, D 50 =9.9μm Fe-Si-BC-Cr-Ni alloy, and D 50 =1 μm Fe-Si-BC-Cr-Ni-P alloy. On the other hand, the amorphous magnetic powder and / or nanocrystalline magnetic powder contained in the spacer pattern layer 112 has a single diameter distribution peak at another diameter D3, which is approximately 1 to 5 μm. In another case, the average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the wiring pattern layer 111 is... 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the spacer pattern layer 112 50 Large. In one embodiment, the average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the wiring pattern layer 111 is large. 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the spacer pattern layer 112 is approximately 5.2–20 μm. 50The thickness is approximately 1–5 μm. In another case, the wiring pattern layer 111 has a greater thickness than the spacer pattern layer 112. In one embodiment, the thickness of the spacer pattern layer 112 is approximately 5–10 μm, while the thickness of the wiring pattern layer 111 is approximately 20–40 μm. In addition to the different parameters illustrated above, other parameters such as material or appearance can also be used as design options to improve relative permeability, insulation properties, and mechanical strength, while reducing the overall thickness of the magnetic body or inductor structure.

[0064] Therefore, in the method for manufacturing the magnetic element according to the present invention, a magnetic body 1 comprising amorphous magnetic powder and / or nanocrystalline magnetic powder and at least one silicon-free glass material distributed between the amorphous magnetic powder and / or nanocrystalline magnetic powder is formed, and a coil 2 is formed in the magnetic body 1. Next, a pair of electrodes 3 are electrically connected to the two terminals 20 of the coil 2, respectively. The coil 2 is formed by embedding a wiring layer 21 in the wiring pattern layer 111 and a via layer 22 in the spacer pattern layer 112 before laminating the wiring pattern layer 111 and the spacer pattern layer 112. Preferably, but not necessarily, the wiring pattern layer 111 and the spacer pattern layer 112 can be formed using the same or similar methods.

[0065] See below. Figures 4-8 The present invention describes a method for forming a magnetic body according to an embodiment of the present invention, wherein the magnetic body may be a multilayer or a non-multilayer magnetic body.

[0066] Please see Figure 4 This is a schematic diagram illustrating the formation of a magnetic body included in one embodiment of the magnetic element of the present invention. In this embodiment, amorphous magnetic powder and / or nanocrystalline magnetic powder 131 is formed from an iron alloy containing Fe, Cr, Si, B, and C elements, and dielectric powder 132, such as insulating oxide powder, is added to at least a portion of the surface of the amorphous magnetic powder and / or nanocrystalline magnetic powder 131 to obtain amorphous magnetic powder and / or nanocrystalline magnetic powder 133. For example, the dielectric powder 132 can be in the form of... Figure 5 The mechanical fusion method shown is used to add the magnetic powder and / or nanocrystalline magnetic powder 131 to the surface area. The pressure head or rotor moves back and forth during rotation, applying pressure to the magnetic powder 131 and the dielectric powder 132, causing the dielectric powder 132 to deform and adhere to the outer surface of the magnetic powder 131. The resulting magnetic powder 133 can be used as... Figure 1BThe amorphous magnetic powder and / or nanocrystalline magnetic powder 101 shown is processed by a co-firing process, with a co-firing temperature, for example, above the softening point of silicon-free glass powder, of 470–500°C. The dielectric powder 132, with a particle size smaller than the amorphous magnetic powder and / or nanocrystalline magnetic powder 131, can be glass powder and / or insulating oxide powder. When, for example, insulating oxide powder 132 is mechanically fused to a portion of the surface of the amorphous magnetic powder and / or nanocrystalline magnetic powder 131, the average particle size D of the insulating oxide powder 132 is... 50 At least compared to the average particle size D of amorphous magnetic powder and / or nanocrystalline magnetic powder 131 50 The particle size is 10 times smaller, and preferably less than 0.1 μm. The insulating oxide powder 132 accounts for approximately 2.5 vol% (volume percentage) or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder 131 in the magnetic body 1, thus the gaps between the amorphous magnetic powder and / or nanocrystalline magnetic powder 131 can be reduced as desired. The insulating oxide powder material can be, for example, oxides of magnesium, titanium, zinc, silicon, or aluminum (MgO, TiO2, ZnO, SiO2, Al2O3), and more preferably, oxides of magnesium, titanium, or zinc (MgO, TiO2, ZnO). When, for example, glass powder is mechanically fused to a portion of the surface of the amorphous magnetic powder and / or nanocrystalline magnetic powder 131, the material of the glass powder can be combined with... Figure 1B The materials of the silicon-free glass 102 described herein may be the same or different. The resulting amorphous magnetic powder and / or nanocrystalline magnetic powder 133 are used as... Figure 1B The amorphous magnetic powder and / or nanocrystalline magnetic powder 101 shown is then co-fired with silicon-free glass 102 at a suitable temperature. This temperature facilitates bonding but does not alter the non-bonded or disordered arrangement of the atoms (or molecules) of the amorphous magnetic powder and / or nanocrystalline magnetic powder 101. For example, this temperature is 50°C higher than the softening point of the silicon-free glass powder 102 but 500°C lower than the crystallization temperature of the amorphous magnetic powder and / or nanocrystalline magnetic powder 101. The magnetic body thus produced can be used as a wiring pattern layer 111 or a spacer pattern layer 112, depending on the material of the amorphous magnetic powder and / or nanocrystalline magnetic powder 101.

[0067] Please see Figure 6 This is a schematic diagram illustrating the formation of a magnetic body included in another embodiment of the magnetic element of the present invention. This embodiment is consistent with the referenced... Figure 4 and Figure 5The illustrated embodiment is similar, except that this embodiment uses amorphous magnetic powder and / or nanocrystalline magnetic powder 135 instead of amorphous magnetic powder and / or nanocrystalline magnetic powder 131, and the dielectric powder 132 is glass powder. The amorphous magnetic powder and / or nanocrystalline magnetic powder 135 is at least partially oxidized amorphous magnetic powder and / or nanocrystalline magnetic powder. The dielectric powder 132 is then mechanically fused to the at least partially oxidized amorphous magnetic powder and / or nanocrystalline magnetic powder 135 to obtain amorphous magnetic powder and / or nanocrystalline magnetic powder 136 having deformable dielectric powder 132 thereon, which is then used as... Figure 1B The amorphous magnetic powder and / or nanocrystalline magnetic powder 101 shown are used as... Figure 1B The amorphous magnetic powder and / or nanocrystalline magnetic powder 101 shown in the figure are then co-fired with silicon-free glass powder 102 at an appropriate temperature to obtain a magnetic body that can be used as a wiring pattern layer 111 or a spacer pattern layer 112.

[0068] Please see Figure 7 This is a schematic diagram illustrating the formation of a magnetic body included in another embodiment of the magnetic element of the present invention. In this embodiment, insulating oxide powder 134 is added... Figure 4 In the amorphous magnetic powder and / or nanocrystalline magnetic powder 133 of the illustrated embodiments, the insulation resistance is improved. Preferably, the average particle size D of the insulating oxide powder 134 is... 50 The average particle size D of amorphous magnetic powder and / or nanocrystalline magnetic powder is less than 133. 50 1 / 10. The average particle size D of insulating oxide powder grade 134 / or silicon-free glass powder grade 102. 50 Less than 0.1 μm. In one embodiment, the insulating oxide powder 134 is obtained by oxidation of a material different from the amorphous magnetic powder and / or nanocrystalline magnetic powder 133, and is attached to the amorphous magnetic powder and / or nanocrystalline magnetic powder 133 by silicon-free glass powder 102. For example, the insulating oxide powder 134 is obtained by oxidation of magnesium, titanium, zinc, silicon or aluminum. The insulating oxide powder 134 in the multilayer magnetic body 1 is about 2.5 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder 133 in the magnetic body 1. In this embodiment, a magnetic body material 15 comprising amorphous magnetic powder and / or nanocrystalline magnetic powder 133 is obtained, which includes amorphous magnetic powder and / or nanocrystalline magnetic powder formed of ferrous alloy, mechanically fused dielectric powder 132, insulating oxide powder 134, and silicon-free glass powder 102. After a co-firing process, the magnetic body material 15 can be formed, for example Figure 1A The magnetic body 1 shown.

[0069] Please see Figure 8This is a schematic diagram illustrating the formation of a magnetic body included in another embodiment of the magnetic element of the present invention. This embodiment is consistent with the referenced... Figure 7 The illustrated embodiment is similar, except that this embodiment uses amorphous magnetic powder and / or nanocrystalline magnetic powder 136 instead of amorphous magnetic powder and / or nanocrystalline magnetic powder 133. In this embodiment, a magnetic body material 16 comprising amorphous magnetic powder and / or nanocrystalline magnetic powder 136 is obtained, which includes amorphous magnetic powder and / or nanocrystalline magnetic powder formed from an iron alloy, mechanically fused dielectric powder 132, insulating oxide powder 134, and silicon-free glass powder 102. After a co-firing process, the magnetic body material 16 can be formed, for example... Figure 1A The magnetic body 1 shown.

[0070] It is important to note that Figure 6 and Figure 8 In the embodiments shown, amorphous magnetic powder and / or nanocrystalline magnetic powder may be spontaneously oxidized during co-firing with silicon-free glass powder 102, rather than being oxidized additionally beforehand.

[0071] As previously described, according to the present invention, a multilayer magnetic body can be formed using low-iron-loss ferrous amorphous or microcrystalline magnetic materials. Amorphous magnetic powders and / or nanocrystalline magnetic powders can be heat-treated to form oxides on their surfaces, achieving an insulating effect. At least one type of silicon-free glass can be mechanically fused onto portions of the magnetic powder. In this way, the silicon-free glass can be distributed between the magnetic powders, and the magnetic powders can be bonded together, for example, by liquid-phase co-firing, to obtain the desired structural strength. Furthermore, the oxide layer formed or added to the surface of the magnetic powder can further increase strength and insulation.

[0072] In summary, when the magnetic powder in the entire magnetic body or only in the first part 11 of the magnetic body comprises powders of at least two particle sizes and is bonded to a silicon-free glass material, as described above, high permeability, high mechanical strength, and high insulation properties can be obtained. For example, the permeability can be increased by 25%, the mechanical strength by 62%, and the insulation properties by 164%. Furthermore, when the spacer pattern layer 112 in the second part 12 of the magnetic body 1 is formed by bonding magnetic powder of a single material to silicon-free glass, if the average particle size (D) of the magnetic powder... 50 Within the range of 1–5 micrometers, the overall thickness of the magnetic body or inductor can be effectively reduced. Furthermore, by adding oxides different from magnetic powders and bonding the powders with silicon-free glass materials, the insulation properties can be appropriately adjusted or improved using the oxides. For power inductor applications, the preferred relative permeability is greater than 25, the insulation value is greater than 0.35 V / μm, and the mechanical strength is greater than 15 MPa.

[0073] Although the invention has been described according to embodiments currently considered to be the most practical and preferred, it should be understood that the invention is not necessarily limited to the disclosed embodiments. Rather, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, consistent with the broadest interpretation, thereby encompassing all such modifications and similar structures.

Claims

1. A magnetic element suitable for power inductors, comprising: A magnetic body comprising amorphous magnetic powder and / or nanocrystalline magnetic powder and at least one silicon-free glass material distributed between the amorphous magnetic powder and / or nanocrystalline magnetic powder; A coil is embedded in the magnetic body; and A pair of electrodes are electrically connected to the two terminals of the coil, respectively.

2. The magnetic element as claimed in claim 1, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder has a first diameter distribution peak at at least a first diameter, and a second diameter distribution peak at a second diameter larger than the first diameter.

3. The magnetic element as claimed in claim 2, wherein the first diameter is 1-2 μm, and the second diameter is 10-20 times the first diameter.

4. The magnetic element as claimed in claim 1, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder has an average particle size D of 1 to 5 μm. 50 .

5. The magnetic element as claimed in claim 1, wherein the coil includes a plurality of wiring layers embedded in a first portion of the magnetic body and a plurality of via layers embedded in a second portion of the magnetic body, and the first portion of the magnetic body and the second portion of the magnetic body differ in at least one parameter.

6. The magnetic element of claim 5, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder contained in the first portion of the magnetic body has a first diameter distribution peak at at least a first diameter, and a second diameter distribution peak at a second diameter larger than the first diameter.

7. The magnetic element of claim 6, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder contained in the second portion of the magnetic body has a single diameter distribution peak at a third diameter.

8. The magnetic element of claim 5, wherein the average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the first portion of the magnetic body is... 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the second part of the magnetic body is greater than that of the magnetic body. 50 .

9. The magnetic element of claim 5, wherein the first portion of the magnetic body includes at least one first magnetic layer, wherein one of the plurality of wiring layers is embedded therein, the second portion of the magnetic body includes at least one second magnetic layer, wherein one of the plurality of via layers is embedded therein, and the thickness of the at least one first magnetic layer is greater than the thickness of the at least one second magnetic layer.

10. The magnetic element of claim 9, wherein the thickness of the at least one second magnetic layer is less than 10 μm, and the thickness of the at least one first magnetic layer is 20-40 μm.

11. The magnetic element of claim 1, wherein the magnetic body comprises at least two different materials of the amorphous magnetic powder and / or nanocrystalline magnetic powder.

12. The magnetic element of claim 1, wherein the magnetic body further comprises an insulating oxide powder having an average particle size D 50 The average particle size D of the amorphous magnetic powder and / or nanocrystalline magnetic powder is smaller than that of the amorphous magnetic powder and / or nanocrystalline magnetic powder. 50 1 / 10 of.

13. The magnetic element of claim 12, wherein the average particle size D of the insulating oxide powder is... 50 Less than 0.1 μm.

14. The magnetic element of claim 1, wherein the magnetic body further comprises an insulating oxide powder formed by oxidation of a material selected from magnesium, titanium, zinc, silicon and aluminum.

15. The magnetic element of claim 1, wherein the magnetic body further comprises an insulating oxide powder, the insulating oxide powder comprising approximately 2.5 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the magnetic body.

16. The magnetic element of claim 1, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder comprises an oxide of a material of the amorphous magnetic powder and / or nanocrystalline magnetic powder.

17. The magnetic element of claim 1, wherein the amorphous magnetic powder and / or nanocrystalline magnetic powder comprises an alloy comprising the elements Fe, Cr, Si, B and C.

18. The magnetic element of claim 1, wherein the silicon-free glass material accounts for approximately 8 vol% or less of the amorphous magnetic powder and / or nanocrystalline magnetic powder in the magnetic body.

19. The magnetic element of claim 1, wherein the silicon-free glass material comprises a SnO-P2O5, V2O5-TeO2, Bi2O3-B2O3, ZnO or A2O-MoO3 system, wherein A is an alkali metal or silver.

20. A method for manufacturing a magnetic element, comprising: A magnetic body is formed, comprising amorphous magnetic powder and / or nanocrystalline magnetic powder and at least one silicon-free glass material distributed between the amorphous magnetic powder and / or nanocrystalline magnetic powder; A coil is formed and embedded within the magnetic body; and A pair of electrodes are formed and electrically connected to the two terminals of the coil, respectively.

21. The method of manufacturing a magnetic element as claimed in claim 20, wherein forming the magnetic body comprises: Process a first mixture comprising the amorphous magnetic powder and / or nanocrystalline magnetic powder and the at least one silicon-free glass material to obtain at least one first layer; Processing a second mixture comprising the amorphous magnetic powder and / or nanocrystalline magnetic powder and the at least one silicon-free glass material to obtain at least one second layer; and The at least one first layer and the at least one second layer are laminated.

22. The method of manufacturing a magnetic element as claimed in claim 21, wherein forming the coil comprises: Before laminating the at least one first layer and the at least one second layer, a wiring layer is embedded in the at least one first layer; as well as Before laminating the at least one first layer and the at least one second layer, a via layer is embedded in the at least one second layer.

23. The method of manufacturing a magnetic element as claimed in claim 22, wherein processing the first mixture comprising the amorphous magnetic powder and / or nanocrystalline magnetic powder and the at least one silicon-free glass material and the second mixture each comprises: Mechanically fuse a glass powder or an insulating oxide powder to at least a portion of the surface area of ​​the amorphous magnetic powder and / or nanocrystalline magnetic powder; as well as The amorphous magnetic powder and / or nanocrystalline magnetic powder, on which the glass powder or the insulating oxide powder is mechanically fused to at least a portion of the surface area, and the at least one silicon-free glass material are co-fired.

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