A computing power inductor device and its fabrication method

Abstract

This invention discloses a computing power inductor and its fabrication method. The computing power inductor includes a magnetic core, a conductor, and terminal electrodes. The conductor is disposed inside the magnetic core and extends outside the magnetic core to form the terminal electrodes. The soft magnetic composite material of the magnetic core includes flattened particles, wherein the ratio of the maximum width of the bottom / top surface of the flattened particles to the thickness of the flattened particles is 2.5-15. The computing power inductor of this invention has higher inductance, higher saturation current, higher temperature rise current, and lower DC resistance, resulting in superior overall electrical performance.

Description

Technical Field

[0001] This invention relates to the field of inductors, and in particular to a computing power inductor and its fabrication method. Background Technology

[0002] The rapid development of renewable energy, mobile communications, and robotics technologies has placed higher demands on power supplies and electronic devices. With the trend towards thinner designs in AI servers, high-end PCs, tablets, and mobile phones, and the inherent requirements for high power, the size and power consumption of components used in these devices are increasingly demanding. Furthermore, DC / DC circuits, as the power supply end, also need to achieve low power consumption while maintaining high power output. To meet these higher standards, a new type of inductor, the copper co-fired power inductor, has emerged. Higher reliability, higher saturation current, and lower losses are the highlights and ongoing development goals of copper co-fired inductors. Computational inductors are a key component of power supply modules for AI and consumer electronics chips. They store and release energy through electromagnetic induction, playing a role in filtering, voltage regulation, energy storage, and suppressing electromagnetic interference. The excellent overall electrical performance and flat design of copper co-fired power inductors perfectly meet the requirements of computing inductor devices. However, existing copper co-fired inductors have relatively low inductance values ​​and high power losses, making it difficult to meet the ever-increasing performance requirements of computing inductor devices.

[0003] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a computing power inductor device and its fabrication method.

[0005] The present invention adopts the following technical solution:

[0006] In a first aspect, a computing power inductor is provided, the computing power inductor comprising a magnetic core, a conductor and a terminal electrode, wherein the conductor is disposed inside the magnetic core and extends out of the magnetic core to form the terminal electrode, and the soft magnetic composite material of the magnetic core comprises flat particles, wherein the ratio of the maximum width of the bottom / top surface of the flat particles to the thickness of the flat particles is 2.5-15.

[0007] Secondly, a method for preparing a computing power inductor is provided, comprising the step of preparing a magnetic core of the computing power inductor from a soft magnetic composite material powder, wherein the soft magnetic composite material powder includes flat particles, wherein the ratio of the maximum width of the bottom / top surface of the flat particles to the thickness of the flat particles is 2.5-15.

[0008] The present invention has the following beneficial effects:

[0009] The soft magnetic composite material of the magnetic core in the computing power inductor of the present invention includes flat particles. By adding flat particles of a specific size, the computing power inductor obtained has a higher inductance value, higher saturation current, higher temperature rise current, and lower DC resistance, resulting in superior overall electrical performance. Attached Figure Description

[0010] Figure 1 This is a front view of the computing power inductor device in a specific embodiment of the present invention;

[0011] Figure 2 This is a side view of the computing power inductor device in a specific embodiment of the present invention;

[0012] Figure 3 This is a scanning electron microscope image of the computing power inductor device according to Embodiment 1 of the present invention;

[0013] Figure 4 This is a scanning electron microscope image of the computing power inductor device according to Embodiment 2 of the present invention. Detailed Implementation

[0014] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0015] In the following specific embodiments of the present invention, the computing power inductor is flat, and the surface in the thickness (height) direction is defined as the side surface. For example, when the computing power inductor is a cuboid, the four surfaces in the thickness (height) direction are the side surfaces; the top and bottom surfaces of the computing power inductor are parallel; the bottom / top surface of the flat particle refers to the surface of the flat particle in the non-thickness direction (such as the top or bottom surface).

[0016] This invention provides a computing power inductor device, which includes a magnetic core, a conductor, and terminal electrodes. The conductor is disposed inside the magnetic core and extends out of the magnetic core to form the terminal electrodes. The soft magnetic composite material of the magnetic core includes flat particles, wherein the ratio of the maximum width of the bottom / top surface of the flat particles to the thickness of the flat particles is 2.5-15.

[0017] In soft magnetic composite materials, apart from flat particles, other particles are non-flat particles. Preferably, the non-flat particles are particles with a sphericity of ≥50%, including spherical particles and / or irregularly shaped particles.

[0018] In some embodiments, the thickness of the flattened particles is 0.3-12 μm.

[0019] In some embodiments, the thickness of the flattened particles is 3-7 μm.

[0020] In some embodiments, when any side of the magnetic core is observed with a scanning electron microscope, the area occupied by the flattened particles is 20-80% of the area of ​​the side.

[0021] In some embodiments, among the flat particles on the side, the angle between the bottom / top surface of the flat particles accounting for more than 90% of the area and the upper and lower bottom surfaces of the computing power inductor does not exceed 30°.

[0022] In some embodiments, the soft magnetic composite material of the computing power inductor contains 75-97 wt% Fe and 1-9 wt% Si, and also contains at least one of Al, Cr, B, C, Nb, Cu, P, and O.

[0023] When Al is present, the Al content is 0.5–8 wt%.

[0024] When Cr is present, the Cr content is 0.5–8 wt%.

[0025] When B is present, the content of B is 0.5–8 wt%.

[0026] When C is present, the C content is 0.5–8 wt%.

[0027] When Nb is present, the Nb content is 0.5–8 wt%.

[0028] When Cu is present, the Cu content is 0.5–8 wt%.

[0029] When P is present, the P content is 0.1–5 wt%.

[0030] When O is present, the O content is 0.1–5 wt%.

[0031] In some embodiments, the magnetic material in the soft magnetic composite material is one of FeSi, FeSiAl, FeSiBNbCu, and FeSiB(C,Cr).

[0032] In some embodiments, the soft magnetic composite material is FeSiAl(P,O).

[0033] In some embodiments, the computing power inductor is a co-fired inductor, which is integrally formed by co-firing a conductor and the soft magnetic composite material powder forming the magnetic core; preferably, the co-fired inductor is a copper magnetic co-fired inductor, and the conductor is copper.

[0034] In some embodiments, the computing power inductor further includes a surface coating, which is disposed on the outer surface of the magnetic core in a region excluding the terminal electrodes. The surface coating can provide corrosion resistance and rust prevention to the surface of the computing power inductor; for example, the surface coating is preferably made of materials such as epoxy resin.

[0035] The present invention also provides a method for preparing a computing power inductor, including the step of making a magnetic core of the computing power inductor from soft magnetic composite material powder, wherein the soft magnetic composite material powder includes flat particles, and the ratio of the maximum width of the bottom / top surface of the flat particles to the thickness of the flat particles is 2.5-15.

[0036] In some embodiments, the following steps are also included in forming the flattened particles: feeding spherical powder and / or irregular powder into a bead mill and flattening the spherical powder and / or irregular powder by grinding media beads.

[0037] The following describes specific embodiments of the present invention.

[0038] Example 1

[0039] In this embodiment, the computing power inductor is a copper co-fired inductor, such as... Figure 1 and 2 As shown, it includes a magnetic core 1, a conductor 2, end electrodes 3, and a surface coating 4. The conductor 2 is disposed inside the magnetic core 1 and extends out of the magnetic core to form the end electrodes 3. The surface coating 4 is disposed on the outer surface of the co-fired inductor of the magnetic core, excluding the end electrodes. The soft magnetic composite material of the magnetic core contains 88.1 wt% Fe, 8 wt% Si, 3.5 wt% Al, 0.2 wt% P, and 0.2 wt% O. The soft magnetic composite material includes flat particles, the ratio of the maximum width of the bottom surface of the flat particles to the thickness of the flat particles is 2.5-5, and the thickness of the flat particles is 3-7 micrometers.

[0040] The fabrication process of the computing power inductor device in this embodiment includes the following steps (all process parameters are well known in the art):

[0041] 1. Powder preparation: Spherical magnetic powder and / or irregular magnetic powder are placed into a bead mill, an insulating medium is added, and the spherical powder and / or irregular powder are flattened by the grinding beads to obtain flat magnetic particles; the spherical magnetic particles and flat magnetic particles are coated and granulated to produce a soft magnetic composite material powder with good flowability and easy pressing (containing 40wt% non-flat particles and 60% flat particles);

[0042] 2. Molding: The copper core is inserted into the soft magnetic composite material powder and a portion of the conductor is led out, and then molded into a single piece to form a green blank;

[0043] 3. Heat treatment: The green body is subjected to heat treatment;

[0044] 4. Forming end electrodes: The copper core is bent to form end electrodes;

[0045] 5. Forming a surface coating: Depositing a functional coating such as a corrosion-resistant coating on the surface of the inductor, and then performing laser peeling on the terminal electrodes to obtain the computing power inductor.

[0046] like Figure 3 The image shown is a side view of the device of this embodiment observed under a scanning electron microscope. From the side view of the magnetic core of the computing power inductor, the area occupied by the flat particles is 43% of the total area, and the area occupied by the non-flat particles is 57%. Furthermore, among the flat particles, the angle between the bottom / top surface of the flat particles, which account for more than 92% of the area, and the top and bottom surfaces of the computing power inductor does not exceed 30°.

[0047] Comparative Example 1

[0048] The difference from Example 1 is that the powder preparation does not contain flat particles, but the manufacturing process and other structures are the same as in Example 1.

[0049] The copper co-fired inductor device prepared in Example 1 has an inductance of 153 nH (1 MHz), a saturation current of 71 A, a temperature rise current of 64 A, and a DC resistance of 0.17 mΩ. In contrast, the inductor device in Comparative Example 1 has an inductance of 138 nH (1 MHz), a saturation current of 70 A, a temperature rise current of 55 A, and a DC resistance of 0.19 mΩ. Compared to the copper co-fired inductor device in Example 1, the copper co-fired inductor device in Example 1 has a higher inductance, higher saturation current and temperature rise current, and lower DC resistance (resulting in lower power loss), demonstrating superior overall electrical performance.

[0050] Example 2

[0051] The computing power inductor in this embodiment is a copper co-fired inductor. The difference from Embodiment 1 is that the soft magnetic composite material of the magnetic core in this embodiment contains 89.5 wt% Fe, 7 wt% Si, 1.5 wt% Al, 1 wt% P, and 1 wt% O. The ratio of the maximum width of the bottom surface of the flattened particles to the thickness of the flattened particles is 3.5-7, and the thickness of the flattened particles is 3-7 micrometers. During the powder preparation process, the obtained soft magnetic composite material powder contains 50 wt% non-flattened particles and 50% flattened particles. Other structures and processes are the same as in Embodiment 1.

[0052] like Figure 4The image shown is a side view of the device of this embodiment observed under a scanning electron microscope. From the side view of the magnetic core of the computing power inductor, the area occupied by the flat particles is 36% of the area of ​​the side view, and the area occupied by the non-flat particles is 64%. Furthermore, among the flat particles, the angle between the bottom / top surface of the flat particles, which account for more than 94% of the area, and the top and bottom surfaces of the computing power inductor does not exceed 30°.

[0053] Comparative Example 2

[0054] The difference from Example 2 is that the powder preparation does not contain flat particles, but the manufacturing process and other structures are the same as in Example 2.

[0055] The copper co-fired inductor device prepared in Example 2 has an inductance of 124 nH (1 MHz), a saturation current of 91 A, a temperature rise current of 62 A, and a DC resistance of 0.15 mΩ. In contrast, the inductor device in Comparative Example 2 has an inductance of 119 nH (1 MHz), a saturation current of 86 A, a temperature rise current of 57 A, and a DC resistance of 0.17 mΩ. Compared to the copper co-fired inductor device prepared in Example 2, the copper co-fired inductor device has a higher inductance, higher saturation current and temperature rise current, and lower DC resistance (resulting in lower power loss), demonstrating superior overall electrical performance.

[0056] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A computing power inductor device, characterized in that, The computing power inductor includes a magnetic core, a conductor, and terminal electrodes. The conductor is disposed inside the magnetic core and extends out of the magnetic core to form the terminal electrodes. The soft magnetic composite material of the magnetic core includes flat particles, wherein the ratio of the maximum width of the bottom or top surface of the flat particles to the thickness of the flat particles is 2.5-15. When observing any side of the magnetic core with a scanning electron microscope, the area occupied by the flat particles is 20-80% of the area of ​​the side surface. Among the flat particles on the side surface, the angle between the bottom or top surface of the flat particles accounting for more than 90% of the area and the upper and lower bottom surfaces of the computing power inductor does not exceed 30°.

2. The computing power inductor device as described in claim 1, characterized in that, The thickness of the flattened particles is 0.3-12 μm.

3. The computing power inductor device as described in claim 1, characterized in that, The thickness of the flattened particles is 3-7 μm.

4. The computing power inductor device as described in claim 1, characterized in that, The soft magnetic composite material of the computing power inductor contains 75-97 wt% Fe and 1-9 wt% Si, and also contains at least one of Al, Cr, B, C, Nb, Cu, P, and O. When Al is present, the Al content is 0.5~8 wt%; When Cr is present, the Cr content is 0.5~8 wt%; When B is present, the B content is 0.5~8 wt%; When C is present, the C content is 0.5~8 wt%; When Nb is present, the Nb content is 0.5~8 wt%; When Cu is present, the Cu content is 0.5~8 wt%; When phosphorus (P) is present, the P content is 0.1~5 wt%; When O is present, the O content is 0.1~5wt%.

5. The computing power inductor device as described in claim 1, characterized in that, The magnetic material in the soft magnetic composite material is one of FeSi, FeSiAl, FeSiBNbCu, FeSiBC, FeSiBCr, and FeSiBCCr.

6. The computing power inductor device as described in claim 1, characterized in that, The computing power inductor is a co-fired inductor, which is integrally formed by co-firing a conductor and the soft magnetic composite material forming the magnetic core.

7. The computing power inductor device as described in claim 6, characterized in that, The co-fired inductor is a copper magnetic co-fired inductor, and the conductor is copper.

8. The computing power inductor device as described in claim 1, characterized in that, The computing power inductor also includes a surface coating, which is disposed on the outer surface of the magnetic core in the area excluding the terminal electrodes.

9. A method for fabricating a computing power inductor device according to any one of claims 1-8, characterized in that, The process includes the step of making the magnetic core of the computing power inductor from a soft magnetic composite material.

10. The preparation method according to claim 9, characterized in that, It also includes the following steps to form the flattened particles: putting spherical powder and / or irregular powder into a bead mill and flattening the spherical powder and / or irregular powder by grinding media beads.

Images