High-quality-factor magnetic core inductor on resin substrate and design method

Abstract

The invention provides a high-quality-factor magnetic core inductor on a resin substrate and a design method, and the method comprises the following steps: 1, designing a planar spiral inductor structure with variable line width and line distance, gradually increasing the line width of an inductance coil from an inner turn to an outer turn, and reducing the influence of area enlargement caused by the increase of the line width of the inductor; the line distance between the coils is gradually reduced from the inner turn to the outer turn; and 2, a semi-cured flexible composite magnetic film only needing hot pressing integration is prepared, after the magnetic powder filler of the semi-cured flexible composite magnetic film is subjected to high-temperature oxidation coating, the resistivity is improved, and eddy-current loss under high frequency is effectively restrained. The magnetic film is integrated on a designed air core inductor in a hot pressing mode, and then preparation of the magnetic core inductor can be completed. The designed magnetic core inductor is excellent in performance, the inductance value of the magnetic core inductor can reach 280 nH at 190 MHz, and the quality factor of the magnetic core inductor can also reach 88 at 50 MHz.

Description

Technical Field

[0001] The invention belongs to the technical field of integrated magnetic devices of printed circuit boards, in particular to a design method of a high quality factor magnetic core inductor on a resin substrate. Background Art

[0002] With the rapid development of information technology, high integration, low power consumption, micro size and high reliability have become the development direction of electronic circuit integrated components. Based on this background, the design of power management modules tends to use integrated inductors or integrated transformers to reduce the volume, shorten the transmission path, and reduce the impact of additional resistance and parasitic capacitance and inductance to improve the overall efficiency of the system.

[0003] The planar spiral inductor structure widely used in package-level integrated inductors has the largest magnetic field intensity at its center. However, since the eddy current in the center of the spiral is the strongest and the eddy current loss is serious, and the outer turn coil far away from the center of the spiral is dominated by ohmic loss, its performance at high frequencies is poor. The magnetic core material added to the inductor will inevitably introduce hysteresis loss, further weakening the high-frequency performance of the integrated inductor. Therefore, there is an urgent need to design an inductor structure with low eddy current loss at high frequencies. At the same time, the required magnetic core material should also have good high-frequency performance and low hysteresis loss, and its integration process should be compatible with board-level packaging and have low manufacturing costs. Summary of the invention

[0004] In view of the status and shortcomings of the prior art, the present invention provides a design method for a high-quality factor magnetic core inductor on a resin substrate. The method reduces the eddy current loss at high frequency by increasing the resistance value of the inner turn of the integrated inductor winding coil, and reduces the resistance value of the outer turn coil to reduce the ohmic loss, that is, the line width of the coil gradually increases from the inner turn to the outer turn; in order to maintain the characteristics of miniaturization of the inductor and reduce the impact of the area increase caused by the increase in the inductor line width, the line spacing between the coils gradually decreases from the inner turn to the outer turn, and a planar spiral inductor structure with variable line width and line spacing is successfully designed. At the same time, a semi-cured flexible composite magnetic film that only needs hot pressing integration is prepared. After the magnetic powder filler is coated with high-temperature oxidation, the resistivity is improved, and the eddy current loss at high frequency can be effectively curbed. The magnetic film is hot-pressed and integrated onto the designed air-core inductor to complete the preparation of the magnetic core inductor.

[0005] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0006] A method for designing a high quality factor magnetic core inductor on a resin substrate comprises the following steps:

[0007] Step 1: Design of high quality factor planar spiral air core inductor

[0008] (1.1) The winding of the coil on the resin substrate is a planar spiral quadrilateral structure. The coil is made of metal material. The first turn of the coil located at the innermost side includes two vertical segments and a horizontal segment connected between the vertical segments. The line spacing of the first turn of the coil is denoted by Di, and the line spacing is the distance between the two vertical segments. Di is 1000-3000 μm. The line width of the first turn of the coil is denoted by w, and w is 100-300 μm. The coil thickness is denoted by tcu, and tcu is 20-70 μm.

[0009] (1.2) Winding a second coil on the outer side of the first coil in step (1.1) away from the center, the coil width becomes w×(Δw), the line spacing between the second coil and the first coil is s, Δw is the increase ratio of the coil width, s is the distance between the left vertical section of the second coil and the left vertical section of the first coil, Δw is 1.0 to 2.0, and s is 200 to 1000 μm;

[0010] (1.3) Wind the third coil on the outside of the second coil in step (1.2) above, and the coil width becomes w×(Δw) 2 , the line spacing between the third turn coil and the second turn coil is s-Δs, the line spacing is the distance between the left vertical segment of the third turn coil and the left vertical segment of the second turn coil, Δs is the reduction of the line spacing, which has no direct relationship with the line width, and 3×Δs is less than s, Δs is 50-300μm, and the coil thickness is tcu;

[0011] (1.4) Wind the fourth coil on the outside of the third coil in step (1.3) above, and the coil width becomes w×(Δw) 3 , the line distance between the fourth turn coil and the third turn coil is s-2×Δs, the line distance is the distance between the left vertical section of the fourth turn coil and the left vertical section of the third turn coil, and the coil thickness is tcu;

[0012] (1.5) Wind the fifth coil based on the fourth coil in step (1.4) above, and the coil width becomes w×(Δw) 4 , the line spacing between the third turn coil is s-3×Δs, the line spacing is the distance between the left vertical segment of the fifth turn coil and the left vertical segment of the fourth turn coil, the coil thickness is tcu, the winding is completed, and the design of the high quality factor planar spiral air-core inductor is completed;

[0013] Step 2: Prepare semi-cured flexible composite magnetic film and hot press integrated magnetic core inductor

[0014] (2.1) 40 g of Fe-Cr-Si amorphous magnetic powder is placed in a box furnace, annealed and sintered at 300-500° C. for 1-6 h, and after natural cooling, ground to obtain high-temperature oxidized coated magnetic powder;

[0015] (2.2) Dispersing the magnetic powder prepared in step (2.1) above into a mixture of 10 g of epoxy resin and polyimide stock solution, wherein the mass ratio of epoxy resin to polyimide is 4:1, and mechanically stirring for 2 h at a stirring rate of 450 rpm to obtain a mixture;

[0016] (2.3) Add 0.25 g of dicyandiamide and 0.01 g of 2-methylimidazole to the mixture of step (2.2), continue heating and mechanical stirring for 2 h, and obtain a uniformly mixed magnetic slurry;

[0017] (2.4) coating the magnetic slurry mixed evenly in step (2.3) on a PET film, placing it in a 130° C. forced air oven, and semi-curing it for 15 minutes to obtain a semi-cured flexible composite magnetic film;

[0018] (2.5) The semi-cured flexible composite magnetic film in step (2.4) is hot-pressed and integrated onto the high-quality factor planar spiral air-core inductor designed in step (1.5).

[0019] As a preferred embodiment, the resin substrate is one of a phenolic resin substrate, an epoxy resin substrate, and a polyester resin substrate.

[0020] As a preferred embodiment, the coil is one of an aluminum coil, a copper coil and a silver coil.

[0021] As a preferred embodiment, Di, w and tcu are 2000 μm, 300 μm and 60 μm respectively.

[0022] As a preferred embodiment, Δw and s are 1.4 and 1000 μm respectively.

[0023] As a preferred embodiment, Δs is 150 μm.

[0024] As a preferred embodiment, the annealing temperature in step (2.1) is 300° C. and the holding time is 2 h.

[0025] As a preferred embodiment, in the step (2.5), the integration temperature of the semi-cured flexible composite magnetic film is 160° C., the heating rate is 5° C. / min, and the pressure is 1 MPa.

[0026] The second object of the present invention is to provide a high quality factor magnetic core inductor on a resin substrate, which is obtained by the design method.

[0027] The present invention designs a planar spiral inductor structure with variable line width and line spacing, gradually increasing the line width of the inductor coil from the inner turn to the outer turn. In order to reduce the impact of the area increase caused by the increase in the inductor line width, the line spacing between the coils gradually decreases from the inner turn to the outer turn; a semi-cured flexible composite magnetic film that only requires hot pressing integration is prepared, and its magnetic powder filler is coated with high-temperature oxidation to improve the resistivity and effectively curb eddy current loss under high frequency. The magnetic core inductor designed by the present invention has excellent performance, and its inductance value can reach 280nH@190MHz, and the quality factor also reaches 88@50MHz.

[0028] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in:

[0029] (1) The designed inductor structure with variable line width and line spacing effectively reduces the ohmic loss of the inductor and the eddy current loss at high frequencies without changing the inductor area. The quality factor of the air-core inductor can reach 265@190MHz.

[0030] (2) The magnetic powder required for preparing the magnetic film was subjected to high-temperature oxidation coating, which increased the resistivity and reduced its eddy current loss at high frequencies.

[0031] (3) The prepared semi-cured composite magnetic film is easy to integrate. When in use, it only needs to be placed on the required device and hot-pressed in a hot press to complete curing and integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a top view of the design of the planar spiral air-core inductor in Example 2;

[0033] Figure 2 It is a design side view of the planar spiral air-core inductor in Example 2;

[0034] Figure 3 The microscopic morphology of the original Fe-Cr-Si amorphous magnetic powder in Example 2;

[0035] Figure 4 This is a microscopic morphology of the Fe-Cr-Si amorphous magnetic powder after high-temperature oxidation coating in Example 2;

[0036] Figure 5 This is a simulation diagram of the performance of the planar spiral air-core inductor designed in Example 2.

[0037] Figure 6 This is a simulation diagram of the magnetic core inductance performance designed in Example 2. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0039] Example 1

[0040] This embodiment provides a method for designing a high-quality factor magnetic core inductor on a resin substrate, comprising the following steps:

[0041] Step 1: Design of high quality factor planar spiral air core inductor

[0042] (1.1) The winding of the coil on the phenolic resin substrate is a planar spiral quadrilateral structure. The coil is made of aluminum metal material. The first turn of the coil located at the innermost side includes two vertical segments and a horizontal segment connected between the vertical segments. The line spacing of the first turn of the coil is denoted by Di, which is the distance between the two vertical segments. Di is 1500 μm. The line width of the first turn of the coil is denoted by w, which is 100 μm. The coil thickness is denoted by tcu, which is 20 μm.

[0043] (1.2) Wind a second coil on the outer side of the first coil in step (1.1) away from the center, and the coil width becomes w×(Δw). The line spacing between the second coil and the first coil is s, Δw is the increase ratio of the coil width, s is the distance between the left vertical section of the second coil and the left vertical section of the first coil, Δw is 1.5, and s is 800 μm;

[0044] (1.3) Wind the third coil on the outside of the second coil in step (1.2) above, and the coil width becomes w×(Δw) 2 , the line spacing between the third turn coil and the second turn coil is s-Δs, the line spacing is the distance between the left vertical segment of the third turn coil and the left vertical segment of the second turn coil, Δs is the reduction of the line spacing, which has no direct relationship with the line width, and 3×Δs is less than s, Δs is 50μm, and the coil thickness is tcu;

[0045] (1.4) Wind the fourth coil on the outside of the third coil in step (1.3) above, and the coil width becomes w×(Δw) 3 , the line distance between the fourth turn coil and the third turn coil is s-2×Δs, the line distance is the distance between the left vertical section of the fourth turn coil and the left vertical section of the third turn coil, and the coil thickness is tcu;

[0046] (1.5) Wind the fifth coil based on the fourth coil in step (1.4) above, and the coil width becomes w×(Δw) 4, the line spacing between the third turn coil is s-3×Δs, the line spacing is the distance between the left vertical segment of the fifth turn coil and the left vertical segment of the fourth turn coil, the coil thickness is tcu, the winding is completed, and the design of the high quality factor planar spiral air-core inductor is completed;

[0047] Step 2: Prepare semi-cured flexible composite magnetic film and hot press integrated magnetic core inductor

[0048] (2.1) 40 g of Fe-Cr-Si amorphous magnetic powder was placed in a box furnace, annealed and sintered at 400°C for 4 h, and then naturally cooled and ground to obtain high-temperature oxide-coated magnetic powder.

[0049] (2.2) Dispersing the magnetic powder prepared in step (2.1) above into a mixture of 10 g of epoxy resin and polyimide stock solution, wherein the mass ratio of epoxy resin to polyimide is 4:1, and mechanically stirring for 2 h at a stirring rate of 450 rpm to obtain a mixture;

[0050] (2.3) Add 0.25 g of dicyandiamide and 0.01 g of 2-methylimidazole to the mixture of step (2.2), continue heating and mechanical stirring for 2 h, and obtain a uniformly mixed magnetic slurry;

[0051] (2.4) The magnetic slurry mixed evenly in step (2.3) is coated on a PET film, placed in a 130° C. forced air oven, and semi-cured for 15 minutes to obtain a semi-cured flexible composite magnetic film.

[0052] (2.5) The semi-cured flexible composite magnetic film in step (2.4) is heated to 160°C at a heating rate of 5°C / min, and is hot-pressed and integrated onto the high-quality factor planar spiral hollow-core inductor designed in step (1.5) at a pressure of 1 MPa.

[0053] Example 2

[0054] This embodiment provides a method for designing a high-quality factor magnetic core inductor on a resin substrate, comprising the following steps:

[0055] Step 1: Design of high quality factor planar spiral air core inductor

[0056] (1.1) The winding of the coil on the epoxy resin substrate is a planar spiral quadrilateral structure. The coil is made of copper metal material. The first turn of the coil located on the innermost side includes two vertical segments and a horizontal segment connected between the vertical segments. The line spacing of the first turn of the coil is denoted by Di, which is the distance between the two vertical segments. Di is 2000 μm. The line width of the first turn of the coil is denoted by w, which is 300 μm. The coil thickness is denoted by tcu, which is 60 μm.

[0057] (1.2) Wind a second coil on the outer side of the first coil in step (1.1) away from the center, and the coil width becomes w×(Δw). The line spacing between the second coil and the first coil is s, Δw is the increase ratio of the coil width, s is the distance between the left vertical section of the second coil and the left vertical section of the first coil, Δw is 1.4, and s is 1000 μm;

[0058] (1.3) Wind the third coil on the outside of the second coil in step (1.2) above, and the coil width becomes w×(Δw) 2 , the line spacing between the third turn coil and the second turn coil is s-Δs, the line spacing is the distance between the left vertical segment of the third turn coil and the left vertical segment of the second turn coil, Δs is the reduction of the line spacing, which has no direct relationship with the line width, and 3×Δs is less than s, Δs is 150μm, and the coil thickness is tcu;

[0059] (1.4) Wind the fourth coil on the outside of the third coil in step (1.3) above, and the coil width becomes w×(Δw) 3 , the line distance between the fourth turn coil and the third turn coil is s-2×Δs, the line distance is the distance between the left vertical section of the fourth turn coil and the left vertical section of the third turn coil, and the coil thickness is tcu;

[0060] (1.5) Wind the fifth coil based on the fourth coil in step (1.4) above, and the coil width becomes w×(Δw) 4 , the line spacing between the third turn coil is s-3×Δs, the line spacing is the distance between the left vertical segment of the fifth turn coil and the left vertical segment of the fourth turn coil, the coil thickness is tcu, the winding is completed, and the design of the high quality factor planar spiral air-core inductor is completed;

[0061] Step 2: Prepare semi-cured flexible composite magnetic film and hot press integrated magnetic core inductor

[0062] (2.1) 40 g of Fe-Cr-Si amorphous magnetic powder was placed in a box furnace, annealed and sintered at 300°C for 2 h, and then naturally cooled and ground to obtain high-temperature oxide-coated magnetic powder.

[0063] (2.2) Dispersing the magnetic powder prepared in step (2.1) above into a mixture of 10 g of epoxy resin and polyimide stock solution, wherein the mass ratio of epoxy resin to polyimide is 4:1, and mechanically stirring for 2 h at a stirring rate of 450 rpm to obtain a mixture;

[0064] (2.3) Add 0.25 g of dicyandiamide and 0.01 g of 2-methylimidazole to the mixture of step (2.2), continue heating and mechanical stirring for 2 h, and obtain a uniformly mixed magnetic slurry;

[0065] (2.4) The magnetic slurry mixed evenly in step (2.3) is coated on a PET film, placed in a 130° C. forced air oven, and semi-cured for 15 minutes to obtain a semi-cured flexible composite magnetic film.

[0066] (2.5) The semi-cured flexible composite magnetic film in step (2.4) is heated to 160°C at a heating rate of 5°C / min, and is hot-pressed and integrated onto the high-quality factor planar spiral hollow-core inductor designed in step (1.5) at a pressure of 1 MPa.

[0067] The top view of the planar spiral air-core inductor in this embodiment is shown in FIG. Figure 1 shown.

[0068] The design side view of the planar spiral air-core inductor in this embodiment is shown in FIG. Figure 2 shown.

[0069] The microscopic morphology of the original Fe-Cr-Si amorphous magnetic powder used in this embodiment is shown in FIG. Figure 3 As shown. The powder is spherical or nearly spherical with a relatively smooth surface.

[0070] The microscopic morphology of the Fe-Cr-Si amorphous magnetic powder after high temperature oxidation coating in this embodiment is shown in FIG. Figure 4 As shown in the figure, it can be seen that there is an obvious coating layer on the surface of the magnetic powder, and the coating layer is relatively rough, which is significantly different from the original magnetic powder without coating.

[0071] The performance simulation of the planar spiral air-core inductor designed in this embodiment is as follows: Figure 5 It can be seen that the performance of the air-core inductor is stable within the first 200MHz, with the inductance maintained at around 160nH, and the quality factor reaches its maximum at 190MHz, which is 265, much higher than the common planar air-core inductor.

[0072] The performance simulation of the magnetic core inductance designed in this embodiment is as follows Figure 6 It can be seen that the inductance of the core inductor has been greatly improved, reaching 280nH at 190MHz, and the quality factor has reached 88@50MHz. Compared with the common planar core inductor, the quality factor has been increased by nearly 1 times.

[0073] Example 3

[0074] This embodiment provides a method for designing a high-quality factor magnetic core inductor on a resin substrate, comprising the following steps:

[0075] Step 1: Design of high quality factor planar spiral air core inductor

[0076] (1.1) The winding of the coil on the polyester resin substrate is a planar spiral quadrilateral structure. The coil is made of metallic silver material. The first turn of the coil located at the innermost side includes two vertical segments and a horizontal segment connected between the vertical segments. The line spacing of the first turn of the coil is denoted by Di, which is the distance between the two vertical segments. Di is 1000 μm. The line width of the first turn of the coil is denoted by w, which is 150 μm. The coil thickness is denoted by tcu, which is 70 μm.

[0077] (1.2) Wind a second coil on the outer side of the first coil in step (1.1) away from the center, and the coil width becomes w×(Δw). The line spacing between the second coil and the first coil is s, Δw is the increase ratio of the coil width, s is the distance between the left vertical section of the second coil and the left vertical section of the first coil, Δw is 1.7, and s is 1000 μm;

[0078] (1.3) Wind the third coil on the outside of the second coil in step (1.2) above, and the coil width becomes w×(Δw) 2 , the line spacing between the third turn coil and the second turn coil is s-Δs, the line spacing is the distance between the left vertical segment of the third turn coil and the left vertical segment of the second turn coil, Δs is the reduction of the line spacing, which has no direct relationship with the line width, and 3×Δs is less than s, Δs is 300μm, and the coil thickness is tcu;

[0079] (1.4) Wind the fourth coil on the outside of the third coil in step (1.3) above, and the coil width becomes w×(Δw) 3 , the line distance between the fourth turn coil and the third turn coil is s-2×Δs, the line distance is the distance between the left vertical section of the fourth turn coil and the left vertical section of the third turn coil, and the coil thickness is tcu;

[0080] (1.5) Wind the fifth coil based on the fourth coil in step (1.4) above, and the coil width becomes w×(Δw) 4 , the line spacing between the third turn coil is s-3×Δs, the line spacing is the distance between the left vertical segment of the fifth turn coil and the left vertical segment of the fourth turn coil, the coil thickness is tcu, the winding is completed, and the design of the high quality factor planar spiral air-core inductor is completed;

[0081] Step 2: Prepare semi-cured flexible composite magnetic film and hot press integrated magnetic core inductor

[0082] (2.1) 40 g of Fe-Cr-Si amorphous magnetic powder was placed in a box furnace, annealed and sintered at 500°C for 6 h, and then naturally cooled and ground to obtain high-temperature oxide-coated magnetic powder.

[0083] (2.2) Dispersing the magnetic powder prepared in step (2.1) above into a mixture of 10 g of epoxy resin and polyimide stock solution, wherein the mass ratio of epoxy resin to polyimide is 4:1, and mechanically stirring for 2 h at a stirring rate of 450 rpm to obtain a mixture;

[0084] (2.3) Add 0.25 g of dicyandiamide and 0.01 g of 2-methylimidazole to the mixture of step (2.2), continue heating and mechanical stirring for 2 h, and obtain a uniformly mixed magnetic slurry;

[0085] (2.4) The magnetic slurry mixed evenly in step (2.3) is coated on a PET film, placed in a 130° C. forced air oven, and semi-cured for 15 minutes to obtain a semi-cured flexible composite magnetic film.

[0086] (2.5) The semi-cured flexible composite magnetic film in step (2.4) is heated to 160°C at a heating rate of 5°C / min, and is hot-pressed and integrated onto the high-quality factor planar spiral hollow-core inductor designed in step (1.5) at a pressure of 1 MPa.

[0087] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for designing a high quality factor magnetic core inductor on a resin substrate, characterized in that The steps include: Step 1: Design of high quality factor planar spiral air core inductor (1.1) The winding of the coil on the resin substrate is a planar spiral quadrilateral structure. The coil is made of metal material. The first turn of the coil located at the innermost side includes two vertical segments and a horizontal segment connected between the vertical segments. The line spacing of the first turn of the coil is denoted by Di, and the line spacing is the distance between the two vertical segments. Di is 1000-3000 μm. The line width of the first turn of the coil is denoted by w, and w is 100-300 μm. The coil thickness is denoted by tcu, and tcu is 20-70 μm. (1.2) Winding a second coil on the outer side of the first coil in step (1.1) away from the center, the coil width becomes w×(Δw), the line spacing between the second coil and the first coil is s, Δw is the increase ratio of the coil width, s is the distance between the left vertical section of the second coil and the left vertical section of the first coil, Δw is 1.0 to 2.0, and s is 200 to 1000 μm; (1.3) Wind the third coil on the outside of the second coil in step (1.2) above, and the coil width becomes w×(Δw) 2 , the line spacing between the third turn coil and the second turn coil is s-Δs, the line spacing is the distance between the left vertical segment of the third turn coil and the left vertical segment of the second turn coil, Δs is the reduction of the line spacing, 3×Δs is less than s, Δs is 50 to 300 μm, and the coil thickness is tcu; (1.4) Wind the fourth coil on the outside of the third coil in step (1.3) above, and the coil width becomes w×(Δw) 3 , the line distance between the fourth turn coil and the third turn coil is s-2×Δs, the line distance is the distance between the left vertical section of the fourth turn coil and the left vertical section of the third turn coil, and the coil thickness is tcu; (1.5) Wind the fifth coil based on the fourth coil in step (1.4) above, and the coil width becomes w×(Δw) 4 , the line spacing between the third turn coil is s-3×Δs, the line spacing is the distance between the left vertical segment of the fifth turn coil and the left vertical segment of the fourth turn coil, the coil thickness is tcu, the winding is completed, and the design of the high quality factor planar spiral air-core inductor is completed; Step 2: Prepare semi-cured flexible composite magnetic film and hot press integrated magnetic core inductor (2.1) 40 g of Fe-Cr-Si amorphous magnetic powder is placed in a box furnace, annealed and sintered at 300-500° C. for 1-6 h, and after natural cooling, ground to obtain high-temperature oxidized coated magnetic powder; (2.2) Dispersing the magnetic powder prepared in step (2.1) above into a mixture of 10 g of epoxy resin and polyimide stock solution, wherein the mass ratio of epoxy resin to polyimide is 4:1, and mechanically stirring for 2 h at a stirring rate of 450 rpm to obtain a mixture; (2.3) Add 0.25 g of dicyandiamide and 0.01 g of 2-methylimidazole to the mixture of step (2.2), continue heating and mechanical stirring for 2 h, and obtain a uniformly mixed magnetic slurry; (2.4) coating the magnetic slurry mixed evenly in step (2.3) on a PET film, placing it in a 130° C. forced air oven, and semi-curing it for 15 minutes to obtain a semi-cured flexible composite magnetic film; (2.5) The semi-cured flexible composite magnetic film in step (2.4) is hot-pressed and integrated onto the high-quality factor planar spiral air-core inductor designed in step (1.5).

2. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: The resin substrate is one of a phenolic resin substrate, an epoxy resin substrate, and a polyester resin substrate.

3. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: The coil is one of a copper coil, an aluminum coil and a silver coil.

4. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: Di, w and tcu are 2000μm, 300μm and 60μm respectively.

5. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: Δw and s are 1.4 and 1000 μm, respectively.

6. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: Δs is 150μm.

7. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: The annealing temperature in the step (2.1) is 300° C. and the holding time is 2 h.

8. The method for designing a high quality factor magnetic core inductor on a resin substrate according to claim 1, characterized in that: In the step (2.5), the integration temperature of the semi-cured flexible composite magnetic film is 160° C., the heating rate is 5° C. / min, and the pressure is 1 MPa.

9. A high quality factor magnetic core inductor on a resin substrate, characterized in that Obtained by the design method described in any one of claims 1 to 6.

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