Magnetic-core-embedded PCB and manufacturing method therefor

Abstract

The present application relates to the technical field of circuit board manufacturing, and discloses a magnetic-core-embedded PCB and a manufacturing method therefor. The manufacturing method for a magnetic-core-embedded PCB comprises: providing a substrate; forming a blind slot on the substrate; inserting a first magnetic adhesive into the blind slot, wherein the first magnetic adhesive is recessed into the surface of the substrate; and curing the first magnetic adhesive. The magnetic-core-embedded PCB and the manufacturing method provided by the present application can mitigate the problem in the prior art of being difficult to flatten a magnetic adhesive protruding from the surface of a substrate after the magnetic adhesive is cured.

Description

A buried magnetic PCB and a manufacturing method thereof

[0001] The present application claims priority to the Chinese patent application No. 202411106722.5, filed on August 13, 2024, and entitled "A buried magnetic PCB and a manufacturing method thereof", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of circuit board manufacturing, and in particular to a buried magnetic PCB and a manufacturing method thereof. BACKGROUND

[0003] With the development of power module PCBs, power converters use buried magnetic technology to replace the traditional scheme of mounting inductance components, which can greatly reduce the surface area occupied by inductance components during mounting, and provides a good solution for the high density and miniaturization of electronic products.

[0004] Currently, it is difficult to process a buried magnetic PCB. In order to improve the overall capacity of the product, a magnetic sheet is usually used. The size of the embedded magnetic sheet is small and the thickness is thin. Automatic grabbing and placing equipment cannot be used for such products. The magnetic sheet needs to be manually placed, but the magnetic sheet itself is brittle and easy to break, and is prone to collision. In addition, the number of magnetic sheets embedded in a single workboard is large, and each board needs to be manually placed with a magnetic sheet. This results in low efficiency and quality problems, which brings great difficulties to production. Therefore, another way of embedding a magnetic core in a PCB has emerged, that is, a magnetic glue is first inserted into the PCB, and then the magnetic glue is cured. Since the magnetic glue contains metal particles, it is not easy to grind the magnetic glue protruding from the board surface after curing treatment. Therefore, the prior art needs to be improved. TECHNICAL PROBLEM

[0005] The purpose of the embodiments of the present application is to provide a buried magnetic PCB and a manufacturing method thereof, which can improve the problem that it is not easy to grind the magnetic glue protruding from the board surface after curing treatment in the related art. TECHNICAL SOLUTION

[0006] The technical scheme adopted by the embodiments of the present application is:

[0007] In a first aspect, the embodiments of the present application provide a manufacturing method of a buried magnetic PCB, comprising:

[0008] providing a substrate;

[0009] processing a blind groove on the substrate;

[0010] inserting a first magnetic glue into the blind groove, the first magnetic glue being recessed from the board surface of the substrate;

[0011] curing the first magnetic glue.

[0012] In a second aspect, the embodiments of the present application provide a buried magnetic PCB, which is processed by the manufacturing method of the buried magnetic PCB.

[0013] The manufacturing method of the buried magnetic PCB provided by the embodiments of the present application has the beneficial effect that, since the blind groove is processed on the substrate first, the first magnetic glue is inserted into the blind groove, the first magnetic glue is concave to the surface of the substrate, and the first magnetic glue is subjected to the curing treatment, the first magnetic glue protruding from the surface of the substrate is conveniently ground flat after the curing treatment of the first magnetic glue.

[0014] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0016] FIG. 1 is a flowchart of the manufacturing method of the buried magnetic PCB in one of the embodiments of the present application;

[0017] FIG. 2 is a top view of a substrate in one of the embodiments of the present application;

[0018] FIG. 3 is a sectional view of the substrate shown in FIG. 2;

[0019] FIG. 4 is a schematic view of processing a blind groove on the substrate shown in FIG. 2;

[0020] FIG. 5 is a sectional view of attaching a protective film on the substrate shown in FIG. 4;

[0021] FIG. 6 is a schematic view of inserting first magnetic glue into the blind groove of the substrate shown in FIG. 5 and removing the protective film;

[0022] FIG. 7 is a sectional view of a first inner layer plate in one of the embodiments of the present application;

[0023] FIG. 8 is a schematic view of manufacturing a circuit on the first inner layer plate shown in FIG. 7;

[0024] FIG. 9 is a schematic view of pressing the substrate shown in FIG. 6, the first inner layer plate shown in FIG. 8 and a second inner layer plate together to obtain an intermediate plate;

[0025] FIG. 10 is a schematic view of processing a connecting hole on the intermediate plate shown in FIG. 9;

[0026] Fig. 11 is a schematic view of inserting a second magnetic glue into the connecting hole shown in Fig. 10 and curing the second magnetic glue to obtain a sub-plate;

[0027] Fig. 12 is a schematic view of pressing two sub-plates shown in Fig. 11 together;

[0028] Fig. 13 is a top view of a substrate in another embodiment of the present application;

[0029] Fig. 14 is a schematic view of inserting a first magnetic glue into the blind slot shown in Fig. 13 and curing the first magnetic glue;

[0030] Fig. 15 is a schematic view of processing an outer through hole and an inner through hole on the substrate shown in Fig. 14. Embodiments of the present application

[0031] In the following description, for the purposes of explanation and not limitation, specific details are set forth, such as particular system configurations, techniques, etc., in order to provide a thorough understanding of the embodiments of the application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

[0032] It is also to be understood that the terminology "and / or" as used herein is used to associate together one or more related items, and that the term includes all possible combinations of the associated items.

[0033] It is to be noted that when an element is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element or indirectly on or connected to the other element by way of one or more other elements. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element by way of one or more other elements.

[0034] It is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like as used herein are intended to refer to the orientation or position of the device or element as shown in the drawings and are used only for convenience in providing a thorough and enabling disclosure of the present application, and are not intended to limit or confine the present application to any particular orientation or position.

[0035] In addition, in the description of the application and the appended claims, the terms "first", "second", "third", etc. are used only for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of use in either order.

[0036] Reference within the specification of this application to "one embodiment" or "some embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of the phrases "in some embodiments," "in some other embodiments," "in other embodiments," "in yet other embodiments," or the like in various places in the specification are not necessarily all referring to the same embodiments, although they can. The terms "including," "comprising," "having," and variations thereof are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. "Multiple" means two or more.

[0037] In order to illustrate the technical solutions of the present application, the following will be described in conjunction with specific drawings and embodiments.

[0038] At present, it is difficult to process a buried magnet PCB. In order to improve the overall feeling of the product, a magnetic sheet is usually used as a magnetic core. The size of the embedded magnetic sheet is small and the thickness is thin. The automatic grabbing and placing equipment cannot be used for such products at present. The magnetic sheet needs to be manually placed by hand. However, the magnetic sheet itself is brittle and easy to break, and is prone to collision. In addition, the number of embedded magnetic sheets in a single workboard is large, and each board needs to be manually placed with a magnetic sheet. Therefore, the efficiency is low and quality problems are prone to occur, which brings great trouble to production. Therefore, another way of embedding a magnetic core in a PCB is to first insert a magnetic glue into the PCB, and then solidify the magnetic glue. Since the magnetic glue contains metal particles, it is not easy to grind the magnetic glue protruding from the surface of the board after solidification. Therefore, the prior art needs to be improved.

[0039] In view of this, the present application provides a buried magnet PCB and a manufacturing method thereof, which can improve the problem that it is not easy to grind the magnetic glue protruding from the surface of the board after solidification in the related art.

[0040] Please refer to FIGS. 1 to 6. In a first aspect, the embodiments of the present application provide a manufacturing method of a buried magnet PCB, comprising:

[0041] S100: providing a substrate 10.

[0042] Specifically, the substrate 10 can be a double-sided copper-free board, that is, both sides of the substrate 10 are not covered with copper foil 70, and are all insulating dielectric materials. The substrate 10 can also be a double-sided copper-clad board, a single-sided copper-clad board, or a multi-layer board formed by pressing at least once. In the present embodiment, the substrate 10 is a double-sided copper-free board. The material of the substrate 10 mainly includes resin, which can be epoxy resin or polyimide resin, polyester resin, polyphenyl ether resin, polytetrafluoroethylene resin, etc., and can also include reinforcing materials such as glass cloth.

[0043] S200: processing a blind groove 20 on the substrate 10.

[0044] Specifically, the blind slot 20 can be processed by laser or mechanical milling. The blind slot 20 can be one or more.

[0045] The thickness of the substrate 10 can be 0.1 mm greater than the depth of the blind slot.

[0046] S300: Insert the first magnetic glue 40 into the blind slot 20, and the first magnetic glue 40 is recessed on the surface of the substrate 10.

[0047] Specifically, a vacuum plug machine can be used to insert the first magnetic glue 40 into the blind slot 20 by using a plug aluminum sheet. Since the insertion area of the first magnetic glue 40 exceeds the normal capacity, the size of the window of the plug aluminum sheet can be increased by 0.1 mm compared with the size of the blind slot 20 as a whole when plugging. The first magnetic glue 40 can be a magnetic conductive glue, which includes a metal magnetic powder and a resin. In order to improve the magnetic permeability of the first magnetic glue 40 after curing, the metal magnetic powder can be selected from high permeability ferrite materials such as manganese zinc ferrite, nickel zinc ferrite, etc. The resin can be an epoxy resin, and the curing agent is mixed in an optimized proportion to ensure the optimal CTE (Coefficient of Thermal Expansion).

[0048] For example, the maximum particle size of the first magnetic glue 40 powder can be not more than 80 um, and the magnetic conductive glue needs to be thawed at room temperature for 4-6 hours and stirred for 15 minutes to heat the tank. The scraper angle is 15 degrees, the scraper speed is 100 mm / s, the scraper pressure is 0.25 MPa, the ink covering knife speed is 200 mm / s, the ink covering knife pressure is 0.2 MPa, and the board is cemented within 15 minutes after printing the first magnetic glue 40.

[0049] It should be noted that the first magnetic glue 40 can be recessed on the surface of the substrate 10 by controlling the parameters of the vacuum plug machine when inserting the first magnetic glue 40 into the blind slot 20. The parameters of the vacuum plug machine can be: vacuum mode, scraper speed 150±10 mm / s, scraper pressure 0.5±0.1 MPa, ink covering knife speed 250±10 mm / s, and ink covering knife pressure 0.2±0.04 MPa. Adjust the parameters of the vacuum plug machine according to the first magnetic glue insertion condition.

[0050] S400: Curing treatment is performed on the first magnetic glue 40.

[0051] Specifically, the horizontal plug-in rack baking plate can be used for curing treatment of the first magnetic glue 40.

[0052] It can be seen from the above that the manufacturing method of the buried magnetic PCB provided in the embodiments of the present application has the following advantages. The blind groove 20 is first machined on the substrate 10, then the first magnetic glue 40 is inserted into the blind groove 20, the first magnetic glue 40 is recessed on the surface of the substrate 10, and the first magnetic glue 40 is subjected to a curing process. Therefore, the first magnetic glue 40 protruding from the surface of the substrate 10 can be easily ground flat after the curing process.

[0053] The manufacturing method of the buried magnetic PCB provided in the embodiments of the present application can directly use the cured first magnetic glue 40 as a magnetic core, without the need to place a magnetic sheet, thereby improving the problem in the related art that the magnetic sheet needs to be manually placed and is easy to break after collision.

[0054] Specifically, the recessed degree of the first magnetic glue 40 recessed on the surface of the substrate 10 is ≤50 μm.

[0055] In the related art, when the substrate 10 is large and the machined blind groove 20 is large, the thickness of different parts of the substrate 10 is deviated, which causes the depth of different parts of the blind groove 20 to be deviated when the blind groove 20 is machined on the substrate 10, thereby affecting the volume of the first magnetic glue 40 inserted into the blind groove 20.

[0056] To improve the above problem, in the present embodiment, the substrate 10 has a to-be-machined area 101; the blind groove 20 is machined on the substrate 10, including:

[0057] Firstly, the area S of the to-be-machined area 101 is obtained.

[0058] For example, the to-be-machined area 101 can be a rectangle, and the area S of the to-be-machined area 101 is the length multiplied by the width of the to-be-machined area 101. The area S of the to-be-machined area 101 can be a design area.

[0059] Secondly, if the area S of the to-be-machined area 101 is greater than a preset value, the thickness of the substrate 10 corresponding to at least two reference points in the to-be-machined area 101 is obtained, and the average value of the thickness of the substrate 10 corresponding to all the reference points is taken as the reference thickness D0 of the substrate 10 corresponding to the to-be-machined area 101; if the area S of the to-be-machined area 101 is less than or equal to the preset value, the third thickness H3 of the substrate 10 corresponding to the midpoint of the to-be-machined area 101 is obtained, and the third thickness H3 is taken as the reference thickness D0 of the substrate 10 corresponding to the to-be-machined area 101.

[0060] Specifically, the substrate 10 can be placed on the reference table of the numerical control router, and the probe of the numerical control router can be used to probe at least two reference points in the to-be-processed region 101 to obtain the thickness of the substrate 10 corresponding to the at least two reference points in the to-be-processed region 101. The left lower corner coordinate and the right upper corner coordinate position or the coordinate position of the same straight line of the to-be-processed region 101 can be taken respectively. The probe of the numerical control router can be used to probe the midpoint of the to-be-processed region 101 to obtain the third thickness H3 of the substrate 10 corresponding to the midpoint of the to-be-processed region 101.

[0061] It can be understood that when the blind groove 20 needs to be processed on the substrate 10, the substrate 10 has a plurality of to-be-processed regions 101. If the area S of the to-be-processed region 101 is greater than the preset value, the thickness of the substrate 10 corresponding to two, three, four or more reference points in the to-be-processed region 101 can be obtained, and the average value of the thickness of the substrate 10 corresponding to all the reference points can be taken as the reference thickness D0 of the substrate 10 corresponding to the to-be-processed region 101.

[0062] For example, if the area S of the to-be-processed region 101 is greater than the preset value, the thickness of the substrate 10 corresponding to four reference points in the to-be-processed region 101 can be obtained, and the average value of the thickness of the substrate 10 corresponding to the four reference points can be taken as the reference thickness D0 of the substrate 10 corresponding to the to-be-processed region 101.

[0063] For example, the preset value can be 100 mm 2 , and the to-be-processed region 101 is a square, and the length and the width of the to-be-processed region 101 are both greater than 10 mm.

[0064] Finally, the substrate 10 corresponding to part of the to-be-processed region 101 is removed based on the reference thickness D0 to obtain the blind groove 20.

[0065] Specifically, the substrate 10 corresponding to part of the to-be-processed region 101 can be removed based on the reference thickness D0 to obtain the blind groove 20.

[0066] By adopting the above scheme, the problem that the depth of different parts of the blind groove 20 is deviated when the blind groove 20 is processed on the substrate 10 due to the deviation of the thickness of different parts of the substrate 10, thereby affecting the volume of the first magnetic glue 40 inserted in the blind groove 20 can be improved.

[0067] It can be understood that the area S of the to-be-processed region 101 is certain when designed, and therefore the volume of the effective first magnetic glue 40 is related to the depth of the depth control router when the blind groove 20 is processed. Because a part of the substrate 10 is reserved at the bottom of the blind groove 20, the reference thickness D0 of the substrate 10 corresponding to the to-be-processed region 101 is more accurate, and the depth value of the depth control router is better determined.

[0068] Wherein, the preset depth can be unilaterally compensated by 0.03mm, and the control depth milling tool path needs to be overlapped. The milling tool diameter is minimum 0.7mm, 1 / 2 tool diameter is greater than or equal to the control depth milling tool path overlap is greater than or equal to 1 / 3 tool diameter, and the minimum needs to be greater than or equal to 0.3mm.

[0069] Optionally, if the area S of the to-be-processed region 101 is greater than a preset value, the first thickness H1 and the second thickness H2 of the substrate 10 corresponding to two reference points in the to-be-processed region 101 are obtained, and the average value of the first thickness H1 and the second thickness H2 is taken as the reference thickness D0 of the substrate 10 corresponding to the to-be-processed region 101. The two reference points are two opposite corners of the to-be-processed region 101. In this way, the first thickness H1 and the second thickness H2 are closer to the average thickness of the to-be-processed region 101.

[0070] Specifically, when the probe of the numerical control milling machine is used to probe two reference points in the to-be-processed region 101, the probe is greater than or equal to 1mm away from the control depth forming edge.

[0071] In the embodiment, the first magnetic glue 40 is subjected to a curing process, including:

[0072] First, the first magnetic glue 40 is subjected to a heating process at a first temperature T1.

[0073] Second, the first magnetic glue 40 is subjected to a heating process at a second temperature T2.

[0074] Finally, the first magnetic glue 40 is subjected to a heating process at a third temperature T3, T3>T2>T1.

[0075] By using the above scheme, the first magnetic glue 40 can be prevented from being rapidly deformed or damaged due to high-temperature baking, thereby preventing the first magnetic glue 40 from generating bubbles and cracks.

[0076] It can be understood that although the first magnetic glue 40 is subjected to heating processes at the first temperature, the second temperature and the third temperature respectively in the embodiments of the present application, the whole is a one-time curing process.

[0077] It should be noted that the low-temperature baking heating process can effectively remove water and volatile substances. The low-temperature baking is a preheating and preliminary drying process, which prepares for subsequent high-temperature baking and avoids deformation or damage of the first magnetic glue 40 caused by direct high-temperature impact. The high-temperature final curing ensures that the water and volatile substances in the first magnetic glue 40 are completely removed, achieving the purpose of final curing.

[0078] Optionally, T1 is 85-95℃, T2 is 115-125℃, and T3 is 145-155℃.

[0079] For example, the first magnetic glue 40 is heated at a first temperature of 90℃ for 30 minutes, heated at a second temperature of 120℃ for 30 minutes, and heated at a third temperature of 150℃ for 60 minutes.

[0080] Optionally, the substrate 10 is attached with a protective film 30, and the blind slot 20 penetrates the protective film 30 when the blind slot 20 is processed on the substrate 10. After the first magnetic glue 40 is inserted into the blind slot 20, the protective film 30 is removed. In this way, the first magnetic glue 40 can be prevented from overflowing to the surface of the substrate 10 and being difficult to remove when the first magnetic glue 40 is inserted into the blind slot 20.

[0081] For example, the protective film 30 can be an IP (Insulating Polymer) film, and the film thickness of the protective film 30 is 25um and the glue layer thickness is 20um.

[0082] It can be understood that the protective film 30 corresponding to the blind slot 20 is removed when the blind slot 20 is processed on the substrate 10. The edge of the area of the protective film 30 corresponding to the blind slot 20 can also be burned by laser, and the parameters are set as follows: energy is 10mj, pulse width is 8us, number of shots is 1shot, mask is 2.2mm, and other positions of the protective film 30 are reserved.

[0083] Optionally, the protective film 30 can be removed by using a sand belt and a ceramic grinding machine.

[0084] Referring to FIGS. 7 to 12, after the first magnetic glue 40 is cured, the method for manufacturing the buried magnetic PCB further includes:

[0085] First, the substrate 10 and the inner layer plate 50 are pressed together to obtain an intermediate plate, and the first magnetic glue 40 faces the inner layer plate 50.

[0086] Specifically, the inner layer plate 50 can be two layers, for example, the inner layer plate 50 can include a first inner plate 501 and a second inner plate 502, and the first inner plate 501, the second inner plate 502 and the substrate 10 are sequentially and laminatedly arranged. The connection layer 60 is arranged between the first inner plate 501 and the second inner plate 502 and between the second inner plate 502 and the substrate 10, and the connection layer 60 can be a semi-cured sheet. The inner layer plate 50 can also be a four-layer plate, a six-layer plate or an eight-layer plate, etc., which is determined according to the multi-layer plate structure.

[0087] The intermediate plate can further include a copper foil 70 laminated on the side of the substrate 10 away from the second inner plate 502, and the connection layer 60 is arranged between the copper foil 70 and the substrate 10.

[0088] Secondly, a connection hole 80 is machined on the middle plate from the side of the inner layer plate 50 away from the substrate 10, and the bottom surface of the connection hole 80 is defined by the first magnetic adhesive 40.

[0089] Specifically, the connecting hole 80 can be machined on the middle plate from the side of the inner layer plate 50 away from the substrate 10 by controlled depth drilling / riveting, laser cutting, or a combination of both.

[0090] Next, insert the second magnetic adhesive 90 into the connection hole 80.

[0091] Specifically, the second magnetic adhesive 90 is inserted by vacuum plugging.

[0092] Then, the second magnetic adhesive 90 is cured to obtain the sub-board.

[0093] Specifically, the second magnetic adhesive 90 can be cured using a horizontal rack baking plate.

[0094] Finally, the two sub-boards are pressed together to obtain a magnetic plate. The first magnetic adhesive 40 of one sub-board is set to correspond with the first magnetic adhesive 40 of the other sub-board, and the second magnetic adhesive 90 of one sub-board is set to correspond with the second magnetic adhesive 90 of the other sub-board. The second magnetic adhesive 90 is located between the first magnetic adhesive 40 of one sub-board and the first magnetic adhesive 40 of the other sub-board.

[0095] Specifically, a connection layer 60 can be set between the two sub-boards, and the two sub-boards are symmetrical about the connection layer 60.

[0096] By adopting the above scheme, the first magnetic adhesive 40 and the second magnetic adhesive 90 can be arranged in a "T" shape, and the first magnetic adhesive 40 and the second magnetic adhesive 90 of the two sub-boards can be arranged in an "I" shape, which can be combined with the coil to form an inductor.

[0097] Optionally, the embedded magnetic plate can be further processed by drilling and high-pressure water washing.

[0098] It is understandable that the method of curing the second magnetic adhesive 90 can refer to the method of curing the first magnetic adhesive 40.

[0099] The first inner plate 501 can be manufactured in the following manner:

[0100] First, a double-sided copper clad laminate is provided, which includes a dielectric layer 51 and two conductive layers 52 respectively disposed on opposite sides of the dielectric layer 51.

[0101] Secondly, the conductive layer 52 is thickened by electroplating.

[0102] Finally, circuitry is fabricated on one of the conductive layers 52 by means of film application, exposure, development, and etching.

[0103] It should be noted that the manufacturing method of the second inner plate 502 can refer to the manufacturing method of the first inner plate 501. The difference is that the two layers of conductive layers 52 of the second inner plate 502 are both manufactured with lines.

[0104] It should also be noted that when the substrate 10 and the inner layer plate 50 are pressed together, the conductive layer 52 of the first inner plate 501 without lines faces away from the second inner plate 502.

[0105] It can be understood that the conductive layer 52 which needs to be machined to form the connecting hole 80 can be etched and removed.

[0106] Optionally, the lines manufactured on the two sub-plate conductive layers 52 include a coil around the second magnetic glue 90, and each layer of the coil is connected by a through hole to form a winding coil around the middle second magnetic glue 90. The winding coil and the solidified first magnetic glue 40 and second magnetic glue 90 form an inductor element.

[0107] Please refer to FIG. 13, FIG. 14 and FIG. 15, in another embodiment, the blind groove 20 is an annular groove.

[0108] By using the above scheme, after the blind groove 20 is inserted into the first magnetic glue 40, an annular magnetic core is formed, lines can be manufactured on the substrate 10, and an outer through hole 100 is machined around the blind groove 20, and an inner through hole 110 corresponding to the outer through hole 100 is machined in the blind groove 20. The lines centered on the blind groove 20 are connected to the inner through hole 110 and the outer through hole 100 in turn, forming a coil structure around the solidified first magnetic glue 40, and the first magnetic glue 40 and the coil structure form an inductor element.

[0109] It can be understood that the winding turns of the annular magnetic core help to realize the mutual conversion between electrical energy and mechanical energy or other forms of energy, and the uniform magnetic field makes the magnetic field more concentrated and uniform, thereby enhancing the strength and stability of the magnetic field, and playing an important role in various electromagnetic functions and energy conversion.

[0110] In a second aspect, the embodiments of the present application provide a buried magnetic PCB, which is processed by the manufacturing method of the buried magnetic PCB of the first aspect.

[0111] The buried magnetic PCB provided by the embodiments of the present application is processed by first machining the blind groove 20 on the substrate 10, then inserting the first magnetic glue 40 into the blind groove 20, the first magnetic glue 40 is recessed on the surface of the substrate 10, and the first magnetic glue 40 is solidified, so that the first magnetic glue 40 protruding from the surface of the substrate 10 is easily ground flat after the solidification of the first magnetic glue 40.

[0112] The buried magnetic PCB provided by the embodiments of the present application can directly use the solidified first magnetic adhesive 40 as a magnetic core, does not need to place a magnetic sheet, and can improve the problem that the magnetic sheet needs to be manually placed in the related art, is low in efficiency, and is easy to break after collision.

[0113] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for manufacturing a buried magnetic PCB, characterized in that, include: Provide substrate; A blind groove is formed on the substrate; A first magnetic adhesive is inserted into the blind groove, and the first magnetic adhesive is recessed into the surface of the substrate; The first magnetic adhesive is cured.

2. The method of claim 1, wherein the buried magnetic PCB is manufactured by the steps of: The substrate has a region to be processed; the process of processing blind grooves on the substrate includes: Obtain the area S of the region to be processed; If the area S of the area to be processed is greater than a preset value, the thickness of the substrate corresponding to at least two reference points in the area to be processed is obtained, and the average value of the thickness of the substrate corresponding to all the reference points is taken as the reference thickness D0 of the substrate corresponding to the area to be processed; if the area S of the area to be processed is less than or equal to the preset value, the third thickness H3 of the substrate corresponding to the center of the area to be processed is obtained, and the third thickness H3 is taken as the reference thickness D0 of the substrate corresponding to the area to be processed. Using the reference thickness D0 as a reference, a portion of the substrate corresponding to the area to be processed is removed to obtain the blind groove.

3. The method of claim 2, wherein the buried magnetic PCB is manufactured by: If the area S of the area to be processed is greater than a preset value, then the first thickness H1 and the second thickness H2 of the substrate corresponding to two reference points in the area to be processed are obtained, and the average value of the first thickness H1 and the second thickness H2 is taken as the reference thickness D0 of the substrate corresponding to the area to be processed. The two reference points are two diagonal points of the area to be processed.

4. The method of claim 1, wherein the buried magnetic PCB is made by: The curing process for the first magnetic adhesive includes: The first magnetic adhesive is heated at a first temperature, T1. The first magnetic adhesive is heated at a second temperature, T2. The first magnetic adhesive is heated at a third temperature, where T3 > T2 > T1.

5. The method of claim 4, wherein the buried magnetic PCB is manufactured by: T1 is 85℃-95℃, T2 is 115℃-125℃, and T3 is 145℃-155℃.

6. The method of claim 1, wherein the buried magnetic PCB is made by: The substrate is covered with a protective film.

7. The method of claim 6, wherein the buried magnetic PCB is manufactured by: When a blind groove is formed on the substrate, the blind groove penetrates the protective film.

8. The method of claim 6, wherein the buried magnetic PCB is manufactured by: After inserting the first magnetic adhesive into the blind groove, the protective film is removed.

9. The method of claim 1, wherein the buried magnetic PCB is made by: The blind groove is an annular groove.

10. The method of claim 1, wherein the buried magnetic PCB is made by: The substrate is one of the following: double-sided copper-free board, double-sided copper-clad board, single-sided copper-clad board, or multilayer board formed by at least one lamination.

11. The method of claim 1, wherein the buried magnetic PCB is made by: The first magnetic adhesive has a depression of ≤50μm on the surface of the substrate.

12. The method of claim 1 to 11, wherein, After curing the first magnetic adhesive, the method for manufacturing the embedded magnetic PCB further includes: The substrate and the inner layer plate are pressed together to obtain an intermediate plate, with the first magnetic adhesive facing the inner layer plate; A connection hole is machined on the intermediate plate from the side of the inner layer plate away from the substrate, and the first magnetic adhesive defines the bottom surface of the connection hole; Insert a second magnetic adhesive into the connection hole; The second magnetic adhesive is cured to obtain a sub-board; The two sub-plates are pressed together to obtain a buried magnetic plate.

13. The method of claim 12, wherein the buried magnetic PCB is made by, The first magnetic glue of one of the sub-boards is arranged correspondingly with the first magnetic glue of another of the sub-boards, and the second magnetic glue of one of the sub-boards is arranged correspondingly with the second magnetic glue of another of the sub-boards, the second magnetic glue being located between the first magnetic glue of one of the sub-boards and the first magnetic glue of another of the sub-boards.

14. The method of claim 12, wherein the buried magnetic PCB is made by, The inner layer board is a double-layer board or a multi-layer board.

15. A buried magnetic PCB, characterized by, The buried magnetic PCB is processed by the manufacturing method of the buried magnetic PCB according to any one of claims 1 to 14.

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