Preparation method of magnetic core integrated inductor

Abstract

The invention belongs to the field of electric appliance elements, and particularly provides a preparation method of a magnetic core integrated inductor, which comprises the following steps of: S1, adopting a silicon substrate as an initial substrate, and etching along the front surface of the initial substrate to form a graphical deep groove with a high aspect ratio; s2, filling metal in the patterned deep groove of the initial substrate to form a metal winding; s3, bonding the front surface of the initial substrate and the surface of the metal winding to the temporary substrate; s4, etching along the back surface of the initial substrate to remove the initial substrate, and transferring the metal winding to the temporary substrate; s5, a magnetic core material is filled to wrap the metal winding, and a magnetic core layer is formed; and S6, the bonding is removed to separate the temporary substrate, and the magnetic core integrated inductor is obtained and comprises a magnetic core layer and a metal winding embedded in the magnetic core layer. The magnetic core integrated inductor prepared through the method has the advantages of being high in inductance density and small in direct-current resistance, simultaneous batch preparation of a large number of metal windings can be achieved, batch production is easy, and array integration is easy.

Description

Technical Field

[0001] This invention belongs to the field of electrical components and relates to the fabrication process of magnetic core inductors. Specifically, it provides a method for fabricating integrated magnetic core inductors. Background Technology

[0002] With the rapid development of high-performance computing and mobile devices, integrated voltage regulators (IVRs) have become a key technology for power management of high-current chips such as processors, offering advantages such as fine-grained power management at the load end, fast dynamic response, high efficiency, and integration. However, traditional discrete inductors are bulky and difficult to integrate, failing to meet the requirements of IVR technology for high inductance density, low DC resistance, and arrayable integrated power inductors. Against this backdrop, this invention proposes a novel method for fabricating magnetic core integrated inductors, aiming to provide power inductors with high inductance density, low DC resistance, and arrayable integration. Summary of the Invention

[0003] The purpose of this invention is to propose a novel method for fabricating magnetic core integrated inductors, aiming to provide power inductors with high inductance density, low DC resistance, and array-integrable design.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A method for fabricating a magnetic core integrated inductor, characterized by comprising the following steps:

[0006] S1. Using a silicon substrate as the initial substrate, patterned deep trenches with a high aspect ratio are etched along the front side of the initial substrate. The depth of the deep trenches is more than 50 micrometers, and the trench width and spacing do not exceed 1 / 2 of the trench depth.

[0007] S2: Fill the patterned deep trenches of the initial substrate with metal to form a metal winding;

[0008] S3: Bond the front side of the initial substrate to the surface of the metal winding onto the temporary substrate;

[0009] S4: Etch along the back side of the initial substrate to remove the initial substrate and transfer the metal winding to the temporary substrate;

[0010] S5: Filler core material covers the metal winding to form a core layer;

[0011] S6: Debonding separates the temporary substrate to obtain a magnetic core integrated inductor, including a magnetic core layer and a metal winding embedded therein.

[0012] Furthermore, in step S1, a first patterned masking layer is formed on the front side of the initial substrate, and anisotropic silicon etching is performed vertically from the front side of the initial substrate by dry etching to form a patterned deep trench based on the first patterned masking layer.

[0013] Furthermore, in step S2, a seed layer metal is deposited on the front side and the deep trench surface of the initial substrate to form a continuous seed layer with a thickness not exceeding 3 micrometers; metal electroplating is performed on the seed layer to completely fill the deep trench with metal; and then the electroplated metal outside the deep trench and the seed layer metal are removed by grinding, chemical mechanical polishing or etching to form a metal winding.

[0014] Furthermore, in step S3, a temporary bonding adhesive is applied to the front side of the initial substrate and the surface of the metal winding, and the temporary bonding adhesive is used to bond the metal winding to the temporary substrate. The temporary substrate is a silicon substrate, a glass substrate, or a ceramic substrate.

[0015] Furthermore, in step S4, the etching is performed using either dry etching or wet etching; specifically, the dry etching is anisotropic dry etching of silicon based on fluorine-based gas or chlorine-based gas; specifically, the wet etching of silicon is wet etching of silicon based on potassium hydroxide etchant, tetramethylammonium hydroxide etchant, or a mixed acidic etchant.

[0016] Furthermore, in step S5, the magnetic core material is filled by printing or lamination. The filling process is carried out under vacuum conditions or vacuum treatment is performed after filling to remove air bubbles.

[0017] After the magnetic core material is filled, it is heated and cured. Then, excess magnetic core material is removed by grinding, chemical mechanical polishing or etching processes to form a magnetic core layer with a flat surface and a preset thickness. The thickness of the magnetic core layer is greater than the thickness of the metal winding.

[0018] Further, in step S1, a first patterned masking layer and a second patterned masking layer are sequentially formed on the front side of the initial substrate. Anisotropic silicon etching is performed vertically from the front side of the initial substrate using dry etching. A connection hole region is formed at a designated position based on the second patterned masking layer. The second patterned masking layer is removed, and then a patterned deep trench is formed based on the first patterned masking layer using the same etching process. Correspondingly, in step S2, while forming the metal winding, the connection hole region is simultaneously metallized to form a metallized connection hole connecting the metal winding. In step S5, the metallized connection hole penetrates the magnetic core layer.

[0019] Furthermore, the method for fabricating the magnetic core integrated inductor also includes: after completing step S1, forming an interface layer on the front side of the initial substrate and the surface of the deep trench through a thermal oxidation process or a chemical vapor deposition process.

[0020] Furthermore, the method for fabricating the magnetic core integrated inductor also includes:

[0021] S7: An additional magnetic core layer is formed on the surface of the metal winding and the same side of the magnetic core layer through printing, lamination, sputtering, electroplating or bonding processes to form a closed magnetic core layer covering the metal winding.

[0022] Based on the above technical solution, the beneficial effect of the present invention is that it provides a method for fabricating a magnetic core integrated inductor, which has the following advantages:

[0023] 1) The present invention can realize a metal winding with high line density (line pitch not exceeding the thickness) and a thickness of more than 50 micrometers. High line density can increase the number of turns of the inductor metal winding in a small inductor area, and a larger metal winding thickness can reduce the resistance of the inductor metal winding, thus providing high inductance density and low DC resistance.

[0024] 2) This invention enables the replacement of the initial substrate with a magnetic core, and the realization of a magnetic core with a metal winding, thereby avoiding the loss caused by the initial substrate and reducing the magnetic resistance, thus further improving the inductance density and enhancing the inductance and quality factor.

[0025] 3) The fabrication process in this invention can be achieved through wafer-level or panel-level processes, enabling the simultaneous batch fabrication of a large number of metal windings, facilitating mass production and easy array integration. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of the method for fabricating the magnetic core integrated inductor in Embodiment 1 of the present invention.

[0027] Figure 2 This is a cross-sectional structural diagram of the magnetic core integrated inductor in Embodiment 1 of the present invention.

[0028] Figure 3 This is a process flow diagram of the method for preparing the magnetic core integrated inductor in Embodiment 2 of the present invention.

[0029] Figure 4 This is a cross-sectional structural diagram of the magnetic core integrated inductor in Embodiment 2 of the present invention.

[0030] Figure 5 This is a process flow diagram of the method for preparing the magnetic core integrated inductor in Embodiment 3 of the present invention.

[0031] Figure 6 This is a cross-sectional structural diagram of the magnetic core integrated inductor in Embodiment 3 of the present invention.

[0032] Figure 7 This is a cross-sectional structural diagram of the magnetic core integrated inductor in Embodiment 4 of the present invention.

[0033] Figure 8 This is a process flow diagram of the method for preparing the magnetic core integrated inductor in Embodiment 5 of the present invention.

[0034] Figure 9 This is a cross-sectional structural diagram of the magnetic core integrated inductor in Embodiment 5 of the present invention.

[0035] In the above figures: 1-Initial substrate; 2-Seed layer; 3-Electroplated metal; 4-Temporary bonding adhesive; 5-Temporary substrate; 6-Magnetic core material layer; 7-Interface layer; 8-First patterned masking layer; 9-Second patterned masking layer; 10-Additional magnetic core layer. Detailed Implementation

[0038] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings; obviously, the described embodiments are only some embodiments of this invention, and not all embodiments.

[0039] Example 1

[0040] This embodiment provides a method for fabricating a magnetic core integrated inductor, the process of which is as follows: Figure 1 As shown, the specific steps include:

[0041] S1. Forming a deep trench with a high aspect ratio on the first surface of the initial substrate, the specific process includes:

[0042] A silicon substrate is used as the initial substrate 1, which has a first surface and a second surface opposite each other. Typically, the upper surface is used as the first surface and the lower surface is used as the second surface.

[0043] A patterned masking layer is formed on the first surface of the initial substrate. The patterned masking layer can be a patterned photoresist masking layer formed by photolithography. The patterned masking layer can also include other material patterned masking layers such as silicon dioxide formed by forming a masking layer thin film, forming a patterned photoresist layer by photolithography, and etching the masking layer thin film to transfer the pattern of the photoresist layer to the masking layer thin film.

[0044] Anisotropic silicon etching is performed on the first surface of the initial substrate using dry etching, perpendicular to the direction of the first surface. Silicon in areas covered by a patterned masking layer is protected from etching, while silicon in areas not covered by the patterned masking layer is etched to form deep trenches. This dry etching can be deep silicon etching, such as Bosch deep silicon etching. Optionally, after etching, the remaining patterned masking layer is removed.

[0045] Since the silicon dry etching process can achieve a fast etching rate of more than 2 micrometers per minute and a depth / width ratio or depth / spacing ratio of more than 10:1, the depth of the deep trench can be more than 50 micrometers, and the trench width and spacing do not exceed 1 / 2 of the trench depth.

[0046] S2: Fill the deep trenches of the initial substrate with metal to form a metal winding. The specific process includes:

[0047] Seed layer metal is deposited on the first surface of the initial substrate and the surface of the deep trench to form a continuous seed layer 2. The seed layer typically includes a titanium, tantalum or titanium-tungsten layer for increasing adhesion and a copper layer for conducting electricity and providing electroplating seeds. The thickness of the seed layer generally does not exceed 3 micrometers, and preferably, the thickness of the seed layer does not exceed 1 micrometer.

[0048] Metal plating is performed on the seed layer so that the deep trenches are completely filled with metal, typically copper. The plating metal not only fills the deep trenches but also covers the first surface of the silicon substrate.

[0049] The electroplated metal 3 and seed layer metal 2 outside the deep trench are removed by grinding, chemical mechanical polishing or etching, while the electroplated metal and seed layer metal inside the deep trench are retained to form a metal winding. Since the thickness of the metal winding is determined by the depth of the deep trench, the line width and spacing of the metal winding are determined by the width and spacing of the deep trench. The thickness of the metal winding is generally above 50 micrometers, and the line width and spacing of the metal winding generally do not exceed 1 / 2 of the thickness.

[0050] The surface of the metal winding exposed at the top of the deep trench is called the first surface of the metal winding, and the other surfaces of the metal winding are covered by the initial substrate;

[0051] S3: Bond the first surface of the initial substrate and the same-side surface of the metal winding in the deep trench to the temporary substrate. The specific process includes:

[0052] The first surface of the initial substrate and the same-side surface of the metal winding in the deep trench, i.e. the first surface of the metal winding, are temporarily bonded to the temporary substrate using a temporary bonding material. The temporary bonding material includes temporary bonding adhesive 4, which includes basic adhesives and additives such as polymer materials. The temporary substrate 5 can be a silicon substrate, a glass substrate, or a ceramic substrate.

[0053] S4: Remove the initial substrate while retaining the metal windings. The specific process includes:

[0054] The initial substrate is etched from the second surface of the initial substrate until the initial substrate is completely removed, leaving the metal winding temporarily bonded to the temporary substrate.

[0055] The initial substrate etching process can be anisotropic dry etching of silicon based on fluorine-based or chlorine-based gases, or wet etching of silicon using potassium hydroxide etchant, tetramethylammonium hydroxide etchant, or mixed acidic etchant (containing nitric acid and hydrofluoric acid). The selection of the initial substrate etching process should take into account the impact of the etching process on the temporary bonding material and the temporary substrate. For example, when the temporary substrate is a silicon substrate, wet etching of silicon should not be selected.

[0056] S5: The magnetic core is formed by covering the metal windings with filling core material. The specific process includes...

[0057] The magnetic core material is filled and cured by methods such as printing and lamination. Preferably, the filling of the magnetic core material is carried out under vacuum conditions or vacuum treatment is performed after completion to avoid air bubbles, so that the magnetic core material 6 completely fills the gaps between the metal winding lines and covers the metal winding. The magnetic core material is magnetic slurry or flexible magnetic film. The magnetic core material includes magnetic material particles and an organic polymer matrix. The magnetic material particles can be soft magnetic material particles such as iron, iron-silicon alloy, iron-nickel alloy, iron-cobalt alloy, and ferrite. The magnetic material particles can also be soft magnetic material particles such as iron, iron-silicon alloy, iron-nickel alloy, iron-cobalt alloy, and ferrite with an insulating layer on the surface.

[0058] Excess magnetic core material is removed by methods such as grinding, chemical mechanical polishing, and etching to form a magnetic core with a flat surface that meets the design thickness requirements. The thickness of the magnetic core is greater than the thickness of the metal winding.

[0059] The surface of the magnetic core facing the temporary substrate is called the first surface of the magnetic core, and the surface of the magnetic core opposite to the first surface is called the second surface of the magnetic core.

[0060] S6: Debonding separates the metal winding and the core covering the metal winding from the temporary substrate. The specific process includes...

[0061] The temporary bonding material is debonded by heating, light irradiation, chemical corrosion, etc., so that the metal winding and the magnetic core covered with the metal winding are separated from the temporary substrate. The residual temporary bonding material (if any) on the metal winding and the magnetic core is cleaned and removed, resulting in a magnetic core integrated inductor composed of a high line density thick metal winding and a magnetic core covered with a metal winding.

[0062] Based on the above steps, this embodiment prepares a magnetic core integrated inductor, such as... Figure 2 As shown, the magnetic core integrated inductor includes: a magnetic core and a metal winding embedded inside the magnetic core. The thickness of the metal winding is generally above 50 micrometers, and the line width and spacing of the metal winding are generally no more than 1 / 2 of the thickness.

[0063] Example 2

[0064] This embodiment provides a method for fabricating a magnetic core integrated inductor, such as... Figure 3 As shown, the difference between its process flow and that of Example 1 is as follows:

[0065] To avoid the impact of the initial substrate etching process on the metal winding in step S4, an interface layer 7 that can withstand the initial substrate etching process is added between the metal winding and the initial substrate to protect the metal winding. The interface layer can be a silicon dioxide layer, a silicon nitride layer, etc. The interface layer is formed on the first surface of the initial substrate and the surface of the deep trench through processes such as thermal oxidation and chemical vapor deposition after step S1 and before step S2.

[0066] The magnetic core integrated inductor prepared in this embodiment is as follows: Figure 4 As shown, the difference between it and the magnetic core integrated inductor provided in Embodiment 1 is that an interface layer 7 is provided between the magnetic core and the metal winding.

[0067] Example 3

[0068] This embodiment provides a method for fabricating a magnetic core integrated inductor, such as... Figure 5 As shown, the difference between its process flow and that of Example 1 is as follows:

[0069] In step S1, when forming a deep trench with a high aspect ratio, the deep trench has a region of normal depth and a region of increased depth; the specific process flow is as follows:

[0070] The initial substrate is a silicon substrate. A patterned first masking layer is formed on the first surface of the initial substrate. The patterned first masking layer is formed by forming a first masking layer thin film, forming a patterned first photoresist layer by photolithography, and transferring the pattern of the first photoresist layer to the first masking layer thin film by etching the first masking layer thin film. The first masking layer can be a silicon dioxide layer, a silicon nitride layer, etc. The opening pattern of the first masking layer is consistent with the pattern of the entire area of ​​the deep trench.

[0071] A patterned second masking layer is formed on a patterned first masking layer. The patterned second masking layer can be a patterned photoresist masking layer formed by photolithography. Alternatively, the patterned second masking layer can be formed by forming a second masking layer thin film, forming a patterned second photoresist layer by photolithography, and transferring the pattern of the second photoresist layer to the second masking layer thin film by etching the second masking layer thin film. The second masking layer can be a photoresist layer, a silicon dioxide layer, a silicon nitride layer, etc. The material of the second masking layer should be different from the material of the first masking layer. The opening pattern of the second masking layer is consistent with the pattern of the region where the depth of the deep trench increases.

[0072] The first anisotropic silicon etching is performed on the first surface of the initial substrate using dry etching, perpendicular to the direction of the first surface. The silicon in the area covered by the patterned second masking layer is protected from etching. The area not covered by the patterned second masking layer, i.e. the area where the deep trench increases in depth, is also not covered by the patterned first masking layer. Therefore, the silicon in this area is etched. The etching depth corresponds to the depth that the deep trench needs to increase in this area according to the design. The dry etching can be deep silicon etching, such as Bosch deep silicon etching process.

[0073] The patterned second masking layer is removed using methods such as wet etching and dry etching.

[0074] Then, a second anisotropic silicon etching is performed perpendicular to the first surface of the initial substrate using dry etching. The silicon in the area covered by the patterned first masking layer is protected from etching, while the silicon in the area not covered by the patterned first masking layer, i.e., the entire deep trench area, is etched. The etching depth corresponds to the normal depth of the deep trench according to the design. The dry etching can be deep silicon etching, such as Bosch deep silicon etching. The trench depth in the normal depth region of the deep trench is the depth of the second anisotropic silicon etching, and the trench depth in the deep trench depth-increasing region is the sum of the depths of the first and second anisotropic silicon etchings. After etching, the remaining patterned first masking layer is removed by wet etching, dry etching, or other methods.

[0075] In step S5, when removing excess magnetic core material by methods such as grinding, chemical mechanical polishing, and etching, the filling metal in the deep trench depth-increasing region should be exposed, while the filling metal in the normal depth region of the deep trench should not be exposed. This allows the filling metal in the deep trench depth-increasing region to form a metal through-hole that passes through the magnetic core and connects to the metal winding, which can be used for the electrical connection between the magnetic core integrated inductor and other electronic components.

[0076] Example 4

[0077] This embodiment provides a method for fabricating a magnetic core integrated inductor, which differs from the process flow of Embodiment 3 in that:

[0078] It also includes: S7: By means of printing, lamination, sputtering, electroplating, bonding, etc., an additional magnetic core layer 10 is added to the first surface of the magnetic core and the first surface of the metal winding, thereby forming a closed magnetic core that completely covers the metal winding, so as to further improve the inductance density and quality factor, such as Figure 7 As shown;

[0079] The additional magnetic core layer can be a magnetic core material layer formed by heating and curing a magnetic slurry or flexible magnetic film comprising magnetic material particles and an organic polymer matrix. Alternatively, it can be a sputtered, electroplated, or bonded magnetic core material layer composed solely of magnetic materials or composed of alternating layers of magnetic materials and insulating materials. The magnetic material particles can be soft magnetic material particles such as iron, iron-silicon alloys, iron-nickel alloys, iron-cobalt alloys, and ferrites. The magnetic material particles can also be soft magnetic material particles such as iron, iron-silicon alloys, iron-nickel alloys, iron-cobalt alloys, and ferrites with an insulating layer on the surface. The sputtered magnetic core material can be a soft magnetic thin film material such as iron-nickel alloys, ferrites, or cobalt-zirconium-tantalum (CZT). The electroplated magnetic core material can be a soft magnetic conductive thin film material such as iron-nickel alloys or iron-nickel-cobalt alloys. The bonded magnetic core material can be a magnetic material film such as iron-nickel alloys, ferrites, or cobalt-zirconium-tantalum.

[0080] Example 5

[0081] This embodiment provides a method for fabricating a magnetic core integrated inductor, such as... Figure 8 As shown, the difference between its process flow and that of Example 1 is as follows:

[0082] It also includes: S7: By means of printing, lamination, sputtering, electroplating, bonding, etc., an additional magnetic core layer 10 is added to the first surface of the magnetic core and the first surface of the metal winding, thereby forming a closed magnetic core that completely covers the metal winding, so as to further improve the inductance density and quality factor.

[0083] The additional magnetic core layer can be a magnetic core material layer formed by heating and curing a magnetic slurry or flexible magnetic film comprising magnetic material particles and an organic polymer matrix. Alternatively, it can be a sputtered, electroplated, or bonded magnetic core material layer composed solely of magnetic materials or composed of alternating layers of magnetic and insulating materials. The magnetic material particles can be soft magnetic material particles such as iron, iron-silicon alloys, iron-nickel alloys, iron-cobalt alloys, and ferrites. The magnetic material particles can also be soft magnetic material particles such as iron, iron-silicon alloys, iron-nickel alloys, iron-cobalt alloys, and ferrites with an insulating layer on the surface. The sputtered magnetic core material can be a soft magnetic thin film material such as iron-nickel alloys, ferrites, or cobalt-zirconium-tantalum (CZT). The electroplated magnetic core material can be a soft magnetic conductive thin film material such as iron-nickel alloys or iron-nickel-cobalt alloys. The bonded magnetic core material can be a magnetic material film such as iron-nickel alloys, ferrites, or cobalt-zirconium-tantalum.

[0084] S8: Through holes are formed through the additional magnetic core layer by methods such as laser drilling and photolithography etching, so that a specific area of ​​the first surface of the metal winding is exposed.

[0085] Seed layer metal is deposited on the surface of the additional magnetic core layer, the surface of the holes, and the exposed area of ​​the first surface of the metal winding to form a continuous seed layer. The seed layer typically includes a titanium, tantalum, or titanium-tungsten layer for increasing adhesion, and a copper layer for conducting electricity and providing a seed for electroplating. Metal electroplating is performed on the seed layer so that the holes are completely filled with metal, typically copper. The electroplated metal not only fills the holes but also covers the surface of the additional magnetic core layer.

[0086] The electroplated metal and seed layer metal outside the holes are completely or partially removed by methods such as grinding, chemical mechanical polishing and / or etching, while the electroplated metal and seed layer metal inside the holes are retained, forming metal through holes that connect the metal winding and the surface of the additional magnetic core layer for electrical connection between the magnetic core integrated inductor and other electronic components.

[0087] Based on the above steps, this embodiment prepares a magnetic core integrated inductor as follows: Figure 9 As shown, a metal through-hole is provided in the additional magnetic core layer to connect the metal winding to the surface of the additional magnetic core layer, for electrical connection between the magnetic core integrated inductor and other electronic components.

[0088] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All disclosed features, or steps in all methods or processes, may be combined in any way except for mutually exclusive features and / or steps.

Claims

1. A method for fabricating a magnetic core integrated inductor, characterized in that, Includes the following steps: S1. Using a silicon substrate as the initial substrate, patterned deep trenches with a high aspect ratio are etched along the front side of the initial substrate. The depth of the deep trenches is more than 50 micrometers, and the trench width and spacing do not exceed 1 / 2 of the trench depth. S2: Fill the patterned deep trenches of the initial substrate with metal to form a metal winding; S3: Bond the front side of the initial substrate to the surface of the metal winding onto the temporary substrate; S4: Etch along the back side of the initial substrate to remove the initial substrate and transfer the metal winding to the temporary substrate; S5: Filler core material covers the metal winding to form a core layer; S6: Debonding separates the temporary substrate to obtain a magnetic core integrated inductor, including a magnetic core layer and a metal winding embedded therein.

2. The method for fabricating the magnetic core integrated inductor according to claim 1, characterized in that, In step S1, a first patterned masking layer is formed on the front side of the initial substrate, and anisotropic silicon etching is performed vertically from the front side of the initial substrate by dry etching to form a patterned deep trench based on the first patterned masking layer.

3. The method for fabricating the magnetic core integrated inductor according to claim 1, characterized in that, In step S2, a seed layer metal is deposited on the front side and deep trench surface of the initial substrate to form a continuous seed layer with a thickness of no more than 3 micrometers. Metal electroplating is performed on the seed layer to completely fill the deep trench with metal. Then, the electroplated metal outside the deep trench and the seed layer metal are removed by grinding, chemical mechanical polishing or etching to form a metal winding.

4. The method for fabricating a magnetic core integrated inductor according to claim 1, characterized in that, In step S3, temporary bonding adhesive is applied to the front side of the initial substrate and the surface of the metal winding, and bonded to the temporary substrate by the temporary bonding adhesive. The temporary substrate is a silicon substrate, a glass substrate, or a ceramic substrate.

5. The method for fabricating a magnetic core integrated inductor according to claim 1, characterized in that, In step S4, the etching is performed using either dry etching or wet etching; the dry etching is specifically anisotropic dry etching of silicon based on fluorine-based gas or chlorine-based gas; the wet etching of silicon is specifically wet etching of silicon based on potassium hydroxide etchant, tetramethylammonium hydroxide etchant or mixed acidic etchant.

6. The method for fabricating a magnetic core integrated inductor according to claim 1, characterized in that, In step S5, the magnetic core material is filled by printing or lamination. The filling process is carried out under vacuum conditions or vacuum treatment is performed after filling to remove air bubbles. After the magnetic core material is filled, it is heated and cured. Then, excess magnetic core material is removed by grinding, chemical mechanical polishing or etching processes to form a magnetic core layer with a flat surface and a preset thickness. The thickness of the magnetic core layer is greater than the thickness of the metal winding.

7. The method for fabricating a magnetic core integrated inductor according to claim 1, characterized in that, The method for preparing the magnetic core integrated inductor further includes: after completing step S1, forming an interface layer between the front side of the initial substrate and the surface of the deep trench through a thermal oxidation process or a chemical vapor deposition process.

8. The method for fabricating the magnetic core integrated inductor according to claim 1, characterized in that, The method for fabricating the magnetic core integrated inductor further includes: S7: An additional magnetic core layer is formed on the surface of the metal winding and the same side of the magnetic core layer through printing, lamination, sputtering, electroplating or bonding processes to form a closed magnetic core layer covering the metal winding.

9. The method for fabricating a magnetic core integrated inductor according to claim 1, characterized in that, In step S1, a first patterned masking layer and a second patterned masking layer are formed sequentially on the front side of the initial substrate. Anisotropic silicon etching is performed vertically from the front side of the initial substrate by dry etching. A connection hole region is formed at a specified position according to the second patterned masking layer. Remove the second patterned masking layer, and then use the same etching process to form a patterned deep trench based on the first patterned masking layer; correspondingly, in step S2, while forming the metal winding, the connection hole area is simultaneously metallized to form a metallized connection hole connecting the metal winding; in step S5, the metallized connection hole penetrates the magnetic core layer.

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