Three-dimensional vertical inductance device and preparation method thereof

Abstract

The invention discloses a three-dimensional vertical inductance device and a preparation method thereof. The three-dimensional vertical inductance device comprises a packaging substrate, a composite magnetic core, a vertical inductance column, a horizontal conductor and an interconnected conductive column. The composite magnetic core is formed by alternately stacking insulating dielectric layers and magnetic layers and is provided with a plurality of vertical inductance columns, each inductance column is composed of a conductive column and a vertical dielectric layer on the periphery of the conductive column, and the vertical dielectric layers are used for isolating the conductive columns from the magnetic layers. The packaging substrate can be of a structure with a plate core or without a plate core, and the composite magnetic core is packaged by embedding the packaging substrate into the blind groove or directly hot-pressing the packaging substrate. The horizontal conductors are connected with the conductive columns to improve the total inductance value, and the interconnected conductive columns achieve connection of the upper substrate and the lower substrate. The three-dimensional vertical inductor disclosed by the invention has good packaging compatibility, can realize a relatively large inductance value in a limited substrate area and height, improves the efficiency and the power density of a power supply, and is suitable for a high-integration power supply scheme.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a three-dimensional vertical inductor device, a preparation method, and an application thereof. The inductor core adopts a multi-layer magnetic film composite structure and is suitable for application scenarios such as high-density packaging, system-level packaging, and integrated vertical power supply systems. Background Art

[0002] With the rapid development of electronic technology, electronic devices are evolving towards miniaturization, high precision, high integration, and high performance. This is particularly true in areas such as high-performance computing (HPC), artificial intelligence (AI) processors, Internet of Things (IoT) devices, portable electronics, and aerospace systems, placing higher demands on the integration, size, and energy efficiency of power management chips. For example, while AI chips continue to increase in computing power, they also face key challenges such as high power density, low power transfer, precise voltage regulation, and ultra-fast transient response.

[0003] Traditional discrete power modules are unable to support the stringent requirements of high-computing chips for instantaneous current and energy efficiency due to their large size and long-distance interconnection losses. Fully Integrated Voltage Regulator (FIVR) technology is considered a key supporting technology for chips in the "post-Moore era" because it can integrate inductors, capacitors, and control circuits on the same substrate to achieve ultra-high power density power supply. However, the full implementation of FIVR is still subject to the integration bottleneck of power inductors. Although the on-chip integration of power switching devices and filter capacitors has become mature, inductors are difficult to achieve high-performance integration due to their complex manufacturing process, becoming the "last mile" problem in the FIVR technology chain.

[0004] Currently, integrated inductors proposed for FIVR still primarily utilize air-core coil structures, but their limited inductance per unit area makes them difficult to meet the demands of modern computing chip power supplies for both miniaturization and efficiency. Embedded core inductors and vertical inductor structures have been proposed to increase magnetic flux density per unit area, but most suffer from complex processes, high costs, or poor packaging compatibility. Therefore, a new integrated inductor solution with a simple structure, superior performance, and ease of packaging and integration is urgently needed. Summary of the Invention

[0005] In view of the above-mentioned defects of the prior art, the present invention provides a three-dimensional vertical inductor device and a preparation method thereof. The inductor core adopts a multi-layer magnetic film composite structure. The invention has good packaging compatibility and can achieve a large inductance within a limited substrate area and height. At the same time, it improves the efficiency and power density of the power supply and is suitable for highly integrated power supply solutions.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] In a first aspect, a three-dimensional vertical inductor device includes a packaging substrate, a composite magnetic core, a vertical inductor column, a horizontal conductor, and an interconnected conductive column;

[0008] The packaging substrate comprises an upper packaging substrate, a core having a blind groove and a lower packaging substrate;

[0009] The composite magnetic core is embedded in the blind slot;

[0010] The composite magnetic core comprises a plurality of insulating dielectric layers and magnetic layers alternately stacked in a vertical direction;

[0011] The composite magnetic core is provided with a plurality of vertical inductor columns; the vertical inductor columns include conductive columns and vertical dielectric layers provided on the periphery of the conductive columns for preventing the conductive columns from contacting the magnetic layer;

[0012] A plurality of interconnected conductive pillars are provided outside the composite magnetic core area;

[0013] The conductive pillars are in contact with the horizontal conductor above or below; and the conductive pillars are electrically connected to each other through the horizontal conductor.

[0014] Preferably, the upper packaging substrate and the lower packaging substrate have multiple layers.

[0015] Preferably, the upper packaging substrate and the lower packaging substrate are connected via the interconnecting conductive pillars.

[0016] Preferably, there is at least one blind slot and the composite magnetic core is equal in number.

[0017] Preferably, each vertical inductor column includes a plurality of conductive columns, and adjacent conductive columns are insulated from each other.

[0018] Preferably, when the conductive column and the horizontal conductor are connected to form a conductive path, the three-dimensional vertical inductor is a single inductor; when the conductive column and the horizontal conductor are connected to form two or more conductive paths, the three-dimensional vertical inductor is a multi-phase inductor.

[0019] In a second aspect, a method for preparing a three-dimensional vertical inductor device is provided. The method is used to realize the three-dimensional vertical inductor device according to the first aspect, and comprises the following steps:

[0020] S1. preparing the composite magnetic core and the packaging substrate;

[0021] S2. Embed the composite magnetic core into the blind slot, and bond the upper packaging substrate, the core, and the lower packaging substrate to form an integral structure through a hot pressing process, with the gap between the composite magnetic core and the packaging substrate being filled with organic matter;

[0022] S3, preparing the vertical inductor column, including:

[0023] S31, drilling a first through hole in a vertical direction of the overall structure and filling the first through hole with an insulating colloid to form the vertical dielectric layer;

[0024] S32, drilling again to form a second through hole in a direction perpendicular to the center of the insulating colloid and outside the composite magnetic core region of the overall structure, and filling the second through hole with conductive material to form the conductive pillar and the interconnected conductive pillar, respectively; the diameter of the first through hole is larger than the diameter of the second through hole;

[0025] S4. Prepare the horizontal conductor; perform patterning on the conductive surfaces of the upper packaging substrate and the lower packaging substrate so that the tops or bottoms of the plurality of conductive pillars are interconnected to form the horizontal conductor and the horizontal conductive path.

[0026] In a third aspect, a method for preparing a three-dimensional vertical inductor device is provided. The method is used to realize the three-dimensional vertical inductor device according to the first aspect, and comprises the following steps:

[0027] S1. preparing the composite magnetic core and the packaging substrate;

[0028] S2. Preparing the vertical inductor column and the interconnected conductive column, including:

[0029] S21, while forming a through groove on the surface of the composite magnetic core, drilling a third through hole in a vertical direction outside the composite magnetic core; filling the through groove and the third through hole with insulating colloid respectively to form the vertical dielectric layer;

[0030] S22, bonding the upper packaging substrate, the composite magnetic core, and the lower packaging substrate to form a combined structure through a hot pressing process;

[0031] S23, drilling a fourth through hole in a direction perpendicular to the center of the third through hole of the combined structure and filling the fourth through hole with conductive material to form the vertical inductor column; the diameter of the third through hole is larger than the diameter of the fourth through hole; simultaneously, drilling a hole again in the insulating colloid at the through slot position and filling the hole with conductive material to form the interconnected conductive column; the upper packaging substrate and the lower packaging substrate are connected via the interconnected conductive column;

[0032] S3. Prepare the horizontal conductor; perform patterning on the conductive surfaces of the upper packaging substrate and the lower packaging substrate to form the horizontal conductor and the horizontal conductive path, so that the tops or bottoms of the multiple conductive columns are interconnected to form a series and parallel structure of multiple vertical inductor columns.

[0033] Preferably, preparing the composite magnetic core comprises:

[0034] S11, preparing the magnetic layer and the insulating dielectric layer; the magnetic layer can be prepared separately or directly on the insulating dielectric layer;

[0035] S12. Alternately stacking the magnetic layers and the insulating medium layers multiple times to form the composite magnetic core.

[0036] As an advantage, it also includes:

[0037] The inductance value of the three-dimensional vertical inductor is adjusted by adjusting the material type and thickness of the magnetic layer, the thickness of the insulating dielectric layer, the number of alternating stacking, and the diameter of the through-hole filled with insulating colloid in the vertical direction of the composite magnetic core;

[0038] Adjusting the number of phases and the inductance of each phase of the three-dimensional vertical inductor device by adjusting the connection mode and quantity in the graphic;

[0039] The coupling coefficient between the multi-phase inductors is adjusted by adjusting the distance between the drilled holes.

[0040] Compared with the prior art, the beneficial effects of the present invention are embodied in:

[0041] 1. Achieving a highly integrated three-dimensional vertical inductor structure: This invention overcomes the limitations of traditional planar wound inductors by embedding a multi-layer magnetic thin film composite structure within the packaging substrate and combining it with a three-dimensional wiring method of conductive pillars and horizontal conductors. This significantly reduces the inductor's board area and meets the requirements of high-density integrated power systems.

[0042] 2. Improve inductance performance by controlling the thickness of the magnetic film and suppressing eddy current losses in the magnetic film: The magnetic layers are insulated and isolated by an insulating dielectric layer, which effectively cuts the eddy current path and significantly suppresses eddy current losses under high-frequency operation. Compared with spirally winding multiple layers of magnetic film on the conductive through-hole, it effectively avoids the influence of the anisotropy of the magnetic film shape on the core characteristics and eliminates the eddy currents in the magnetic film surface caused by radial magnetic lines of force. By stacking multiple layers of magnetic cores along the axial direction of the through-hole, the magnetic induction intensity and inductance per unit area around the through-hole are enhanced. At the same time, the tight coupling of the magnetic core and the short magnetic circuit design help to improve the inductance per unit area and the quality factor.

[0043] 3. Ensure electrical isolation between magnetic materials and metal through-holes to enhance reliability: Double drilling and a double-layer insulating dielectric layer structure are used to effectively insulate the magnetic layer before metal filling, avoiding short circuits and magnetic material degradation, and enhancing the process compatibility and long-term stability of the device.

[0044] 4. Stable structure, suitable for standard packaging substrate process: The composite magnetic core is embedded in the core of the packaging substrate and the overall pressing is achieved through hot pressing and bonding technology. It is compatible with mainstream microelectronics packaging processes and has good mechanical strength and environmental stability. The composite soft magnetic film core has good flexibility and has better mechanical strength and packaging substrate process compatibility and reliability than ferrite and powder core materials. The soft magnetic film has higher magnetic permeability, lower coercive force and higher saturation magnetic induction intensity, providing thinner inductor thickness, larger inductance density per unit area, smaller high-frequency hysteresis loss and greater current capacity.

[0045] 5. Adaptable to high-frequency, high-dynamic response application scenarios: The vertical inductor column current path significantly shortens the current loop length and reduces parasitic parameters. It is suitable for new-generation power management scenarios such as DC-DC converters, PMICs, and AI acceleration chip power supply modules with high current, high frequency, high speed, and high dynamic response. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 1 is a schematic structural diagram of a three-dimensional vertical inductor device according to embodiment 1 of the present invention;

[0047] Figure 2 is a diagram of the stacked structure of the composite magnetic thin film structure of Example 1 of the present invention;

[0048] Figure 3 is a cross-sectional view of a three-dimensional vertical inductor device according to embodiment 1 of the present invention;

[0049] Figure 4 is a flow chart for preparing a three-dimensional vertical inductor device according to Example 2 of the present invention;

[0050] Figure 5 1 is a diagram showing various connections of a three-dimensional vertical inductor device according to a second embodiment of the present invention;

[0051] Figure 6 is a magnetic flux path diagram of a three-dimensional vertical inductor device according to embodiment 2 of the present invention;

[0052] Figure 7 Schematic diagram of the structure of a three-dimensional vertical inductor device manufactured by the preparation method of Example 3 of the present invention;

[0053] Figure 8 is a top view of a two-phase array three-dimensional vertical inductor device according to a fourth embodiment of the present invention;

[0054] Figure 9 This is a network structure diagram of an array-type three-dimensional vertical inductor device according to embodiment 5 of the present invention;

[0055] Figure 10 Schematic diagram of the application of a three-dimensional vertical inductor device on the same side of a PMIC and a load according to embodiment 7 of the present invention;

[0056] Figure 11 Schematic diagram of the application of a three-dimensional vertical inductor device on different sides of a PMIC and a load according to a seventh embodiment of the present invention.

[0057] Among them: 1. packaging substrate; 11. lower packaging substrate; 12. upper packaging substrate; 13. board core; 131. blind slot; 2. composite magnetic core; 21. insulating dielectric layer; 22. magnetic layer; 3. vertical inductor column; 31. vertical dielectric layer; 32. conductive column; 4. horizontal conductor; 5. interconnected conductive column. DETAILED DESCRIPTION

[0058] In order to make the technical means, creative features, objectives and effects of the invention easier to understand, the present invention is further described with reference to specific figures. However, the present invention is not limited to the following implementation cases.

[0059] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0060] As high-performance chips continue to demand ever-increasing power supply response speed, current density, and area efficiency, three-dimensional vertical inductors are becoming a key development direction for on-chip integrated inductors due to their high integration and high-density structural advantages. In existing technologies, coaxial inductor structures are a typical three-dimensional integration solution. However, this solution still has several shortcomings: First, the magnetic core has low magnetic permeability, and the magnetic powder core material used has high magnetic flux path reluctance, which limits the increase in inductance. Second, the core has a high coercivity, which easily generates significant hysteresis losses at high frequencies, seriously affecting the quality factor. Third, powder cores and ferrite cores are prone to cracking and damage during drilling and pressing processes, affecting yield. Fourth, the poor performance of powder cores and ferrite materials leads to poor inductance density and current capability. Fifth, the core structure is fixed, making processing difficult, and lacks flexible magnetic circuit design space, making it difficult to achieve higher inductance and stronger magnetic coupling, limiting its potential for array expansion and multi-device integration. To address these issues, the present invention proposes a three-dimensional vertical inductor device based on a multilayer magnetic thin film composite structure and a method for its preparation. By introducing interlayer insulation structure, vertical conduction path and embedded magnetic core technology, a high-performance, easy-to-process and arrayable three-dimensional inductor structure is achieved, which is particularly suitable for high-frequency, high dynamic response and high-integration power management application scenarios.

[0061] Example 1:

[0062] like Figure 1 A three-dimensional vertical inductor device shown includes a packaging substrate 1, a composite magnetic core 2, a vertical inductor column 3, a horizontal conductor 4; 5, and an interconnected conductive column;

[0063] The packaging substrate 1 includes an upper packaging substrate 12, a core 13 having a blind groove 131 and a lower packaging substrate 11;

[0064] The composite magnetic core 2 is embedded in the blind slot 131;

[0065] like Figure 2 As shown, the composite magnetic core 2 includes a plurality of insulating dielectric layers 21 and magnetic layers 22 alternately stacked in a vertical direction; Figure 3 As shown, the composite magnetic core 2 is provided with a plurality of vertical inductor columns 3; the vertical inductor columns 3 include conductive columns 32 and vertical dielectric layers 31 arranged on the periphery of the conductive columns 32 for blocking contact between the conductive columns 32 and the magnetic layer 22; the alternating stacking of the insulating dielectric layers 21 and the magnetic layers 22 in the composite magnetic core 2 is along the central axis direction of the vertical inductor columns 3, in order to enhance the inductance of the vertical inductor columns 3.

[0066] The horizontal conductor 4 contacts the conductive pillar 32 and can electrically connect multiple conductive pillars 32 to increase the total inductance.

[0067] Specifically, the horizontal conductor 4 is formed by patterning the conductive surfaces attached to the upper surface of the upper packaging substrate 12 and the lower surface of the lower packaging substrate 11 .

[0068] Specifically, when the conductive pillars 32 and the horizontal conductors 4 are connected to form a conductive path, the three-dimensional vertical inductor is a single inductor; when the conductive pillars 32 and the horizontal conductors 4 are connected to form two or more conductive paths, the three-dimensional vertical inductor is a multi-phase inductor.

[0069] The composite magnetic core 2 is formed by alternately stacking magnetic layers 22 and insulating dielectric layers 21 , and vertical inductor columns 3 are introduced into the composite magnetic core to realize a vertical closed path of magnetic flux.

[0070] This embodiment uses a single-layer packaging substrate 1 as an example for illustration, but its structure and process can be flexibly expanded to stacked applications of multi-layer boards to achieve more complex circuit designs and higher wiring density and integration, suitable for connecting power management control chips and external components and chips such as loads. In actual use, the upper packaging substrate 12 can have multiple layers, and the upper packaging substrates 12 are electrically connected through interconnecting conductive pillars 5. The lower packaging substrate 11 can also have multiple layers, and the lower packaging substrates 11 are electrically connected through interconnecting conductive pillars 5. The upper and lower packaging substrates are connected through interconnecting conductive pillars 5. The preparation method of the interconnecting conductive pillars is shown in Example 3.

[0071] Example 2:

[0072] like Figure 4 A method for preparing a three-dimensional vertical inductor device is shown, comprising the following steps:

[0073] S1. Prepare composite magnetic core and packaging substrate;

[0074] Preparation of composite magnetic core includes:

[0075] S11, preparing a magnetic layer and an insulating dielectric layer; the magnetic layer can be prepared separately or directly on the insulating dielectric layer;

[0076] S12. Alternately stacking magnetic layers and insulating dielectric layers multiple times to form a composite magnetic core.

[0077] There are two main ways to prepare composite magnetic cores:

[0078] (1) Sequentially depositing magnetic layers and insulating dielectric layers to form an alternating stacked structure of "magnetic layers / insulating dielectric layers"; the deposition methods include but are not limited to magnetron sputtering, electroplating, chemical plating, and other deposition methods. The materials used include but are not limited to: magnetic layers: CoFeB, NiFe, CoNiFe, CoZrTa, CoZrTaB, CoP, FeCuNbSiB, etc.; insulating dielectric layers: Al2O3, Si3N4, PI, PMMA, SU8, etc.;

[0079] (2) The magnetic layer is prepared by cold rolling, strip spinning, screen printing, etc., and the insulating dielectric layer is prepared on the magnetic layer by sputtering, electrodeposition, spraying, spinning, immersion, oxidation, etc. The materials used include but are not limited to: magnetic layer: CoFeNiSiB, FeSiBC, NiFe, CoNiFe, etc.; insulating dielectric layer: Al2O3, Si3N4, PI, PMMA, SU8, etc.;

[0080] Furthermore, the magnetic layer is prepared by sputtering, and the material includes Ni 45 Fe 55 , CoZrTa, CoZrO, FeBN, CoHfTaPd; the magnetic layer is prepared by electrodeposition, and the materials include Ni 80 Fe 20 、Ni 45 Fe 55 , NiFeMo; if the magnetic layer is prepared by melt spinning, the materials include CoFeNiSiB and FeSiBC; if the magnetic layer is prepared by screen printing, the materials include Ni-Zn and NiZnFeO.

[0081] The insulating layer can be prepared by various methods: sputtering, electrodeposition, spraying, spinning, immersion, oxidation, or using a commercial independent insulating dielectric film. The following examples illustrate: if the insulating layer is prepared by sputtering, the insulating layer can be made of insulating materials such as Al2O3, SiO2, Si3N4, BN, MgO, etc.; or, if the insulating layer is prepared by electrodeposition, the insulating layer can be made of PPy (polypyrrole), PEDOT (3,4-ethylenedioxythiophene monomer), etc., with a conductivity greater than 10 -4 S / cm and less than or equal to 10 5 S / cm partially conductive polymer; or, the insulating layer is prepared by spinning or spraying, and the insulating layer can be an insulating material such as PI (polyimide), PMMA (polymethyl methacrylate), PDMS (polydimethylsiloxane), SU8, etc.; or, the insulating layer is prepared by immersing the insulating medium onto the surface of the magnetic film; or, the insulating layer is prepared by oxidizing to produce an oxide layer on the surface of the magnetic film; or, the insulating layer is prepared by a commercial independent insulating dielectric film, and the selected insulating layer can be an ultra-thin double-sided adhesive insulating material such as PET transparent double-sided adhesive and epoxy resin, hot melt adhesive, polyester, acrylic adhesive film, etc.

[0082] Preparing a package substrate includes:

[0083] Prepare a lower package substrate, a core, and an upper package substrate; form a blind groove in the shape of a localized groove on the core by laser etching or machining; and attach a conductive layer to both the lower surface of the lower package substrate and the upper surface of the upper package substrate. In this embodiment, the conductive surface is copper, and both the upper and lower package substrates are single-sided copper-clad, with the copper surface located on the upper and lower surfaces of the device, respectively.

[0084] The packaging substrates described in the present invention include but are not limited to PCB printed circuit boards, flexible boards, rigid-flex boards, high-density organic packaging substrates, glass substrates, ceramic substrates, etc. Since the processes for various substrates vary, the magnetic core integration processes are slightly different. This invention only illustrates how to combine typical substrate processes to realize the three-dimensional vertical inductor based on the multi-layer magnetic thin film composite structure proposed in the present invention. This invention can be easily combined with different plate processes and implemented in other substrates, which also falls within the scope of protection of the present invention.

[0085] S2. Embed the composite magnetic core into the blind slot and bond the upper package substrate, the core, and the lower package substrate together through a hot pressing process to form an integral structure.

[0086] Place the composite magnetic core into the blind slot area and fill it evenly with epoxy resin or filling glue; heat and cure the glue; align the lower packaging substrate with the upper packaging substrate and perform overall packaging and pressing by hot pressing, bonding or lamination;

[0087] S3. Preparing vertical inductive columns and conductive columns, including:

[0088] S31, drilling a first through hole in a vertical direction in the composite magnetic core region of the overall structure and filling the first through hole with an insulating colloid to form a vertical dielectric layer;

[0089] S32. Drill a second through hole in the vertical direction of the center of the insulating colloid and outside the composite magnetic core area of ​​the overall structure, and fill the second through hole with conductive material to form a conductive column; the diameter of the first through hole is larger than the diameter of the second through hole; the conductive material used for the conductive column can be common metal materials with high electrical conductivity such as copper and aluminum.

[0090] The two drilling directions are both perpendicular to the direction in which the insulating medium layer and the magnetic layer are alternately stacked in the composite magnetic core;

[0091] S4. Prepare a horizontal conductor; perform patterning on the conductive surfaces of the upper packaging substrate and the lower packaging substrate so that the tops or bottoms of multiple conductive pillars are interconnected to form a horizontal conductor and a horizontal conductive path, thereby achieving lateral connection between the multiple conductive pillars and forming a passage.

[0092] The horizontal conductor of the wire structure is formed on the copper surface of the package substrate by photolithography patterning. Figure 5 As shown, the conductive columns of multiple inductor columns are sequentially connected through horizontal conductors to form a structure of multiple vertical inductor columns in series and parallel. The current directions in adjacent units of the conductive columns are the same or opposite. In this embodiment, the current directions in the conductive column units are opposite, as shown in FIG. Figure 6 The magnetic flux path diagram shown can also be optimized by ring connection or serpentine connection.

[0093] In the present invention, the inductance value of the three-dimensional vertical inductor is adjusted by adjusting the material type and thickness of the magnetic layer, the thickness of the insulating dielectric layer, the number of alternating stacking times, and the diameter of the conductive column; the number of phases and the inductance of each phase of the three-dimensional vertical inductor are adjusted by adjusting the connection method and number in the graphic process; and the coupling coefficient between multi-phase inductors is adjusted by adjusting the distance between the drilled holes.

[0094] The three-dimensional vertical inductor device proposed in this invention, based on a multilayer magnetic thin film composite structure, embeds the composite magnetic core (2) within the substrate using an embedding and hot-pressing process. A dual-hole drilling and dielectric filling strategy achieves electrical isolation between the metal vias and the magnetic material, effectively suppressing eddy current effects in the core and improving the inductor quality factor. Furthermore, the use of vertical vias and patterned copper connections enables high-density integration, significantly reducing the inductor's board area and improving current density and power conversion efficiency. It is suitable for power management applications requiring high frequency, high integration, and high dynamic response. The process employed is compatible with conventional substrate processing, facilitating large-scale production.

[0095] Example 3: A method for preparing a three-dimensional vertical inductor device, comprising the following steps:

[0096] S1. Prepare composite magnetic core and packaging substrate;

[0097] S2. Prepare vertical inductive columns and interconnected conductive columns, including:

[0098] S21, while forming a through groove on the surface of the composite magnetic core, drilling a third through hole in a vertical direction outside the composite magnetic core, and filling the through groove and the third through hole with insulating colloid to form a vertical dielectric layer;

[0099] S22, bonding the upper packaging substrate, the composite magnetic core, and the lower packaging substrate to form a combined structure through a hot pressing process;

[0100] S23, drilling a fourth through hole again in a direction perpendicular to the center of the third through hole in the combined structure, and filling the fourth through hole with conductive material to form an inductor column; the diameter of the third through hole is larger than the diameter of the fourth through hole; simultaneously, drilling a hole in the insulating colloid at the through slot position of the composite magnetic core and filling the hole with conductive material to form an interconnected conductive column to provide a connection between the upper package substrate wire and the lower substrate wire;

[0101] The above drilling directions are all perpendicular to the direction in which the insulating dielectric layers and the magnetic layers in the composite magnetic core are alternately stacked;

[0102] S3, prepare horizontal conductors; perform patterning on the conductive surfaces of the upper package substrate and the lower package substrate to form horizontal conductors and horizontal conductive paths, so that the tops or bottoms of the conductive columns in the multiple vertical inductor columns are interconnected to form a structure of multiple vertical inductor columns in series and parallel connection; interconnect the conductive columns with the upper package substrate wires and the upper package substrate wires to form signal and power transmission paths, such as Figure 7 shown.

[0103] Example 4:

[0104] like Figure 8 The method for fabricating a three-dimensional vertical inductor based on a multilayer magnetic thin film composite structure is based on the process of Example 2 and further includes: in step 3, during secondary drilling, two or more secondary through-holes may be drilled within the first through-hole, forming multiple conductive pillars within the first through-hole. The conductive pillars are insulated from each other and have a uniform structure. The currents in adjacent conductive pillar units within the same first through-hole are directed in the same or opposite directions. In step 4, horizontal conductors are patterned on the copper surface of the package substrate to sequentially connect the multiple conductive pillars, forming a structure with multiple conductive pillars connected in series and in parallel.

[0105] Example 5:

[0106] like Figure 9The method for preparing a three-dimensional vertical inductor based on a multi-layer magnetic thin film composite structure shown in the figure can realize an array-type three-dimensional vertical inductor network structure. Based on the process of Example 2, multiple composite magnetic cores are prepared in step S1; in step S2, multiple composite magnetic cores are embedded in batches on a large-area packaging substrate, and multiple conductive columns are constructed in each composite magnetic core, which can be connected to the outside through corresponding horizontal conductors. The method also includes logically connecting the vertical inductors at different positions in the array in a series, parallel or distributed network manner according to the system power supply or voltage regulation requirements to form a programmable inductor array.

[0107] Example 6:

[0108] A preparation method for a three-dimensional vertical inductor based on a multi-layer magnetic thin film composite structure realizes the optimization of a high-frequency, low-loss three-dimensional vertical inductor structure on the basis of Example 2, and the steps are similar to those of Example 2; in the design stage, the diameter and spacing of the conductive columns are optimized, the coupling coefficient is optimized, and the skin effect and parasitic capacitance are reduced; a magnetic layer with better eddy current suppression effect (such as layered granular magnetic film and rubber magnetic sheet) is selected, and the thickness and dielectric constant of the insulating medium layer are reasonably designed to minimize the loss at high frequency.

[0109] Example 7:

[0110] A vertical inductor-capacitor co-packaging structure suitable for power chip integrated packaging, comprising: steps 1-4 are the same as those in Example 2, and by controlling the number of three-dimensional vertical inductors, the power management chip and the load can be controlled to be on the same side or different sides of the packaging substrate; when the power management chip and the load are required to be on the same side of the packaging substrate, an even number of the three-dimensional vertical inductors is obtained, such as Figure 10 The three-dimensional vertical inductor device provided by the present invention is applied on the same side of the PMIC and the load; the three-dimensional vertical inductor can be located at the top, middle and bottom layers of the package substrate. Figure 10 The three-dimensional vertical inductor in the package substrate provided by the present invention is located in the middle layer of the package substrate. Multilayer boards are laminated on the upper and lower sides of the inductor and are connected by multilayer wires. The metal layers can be connected by non-inductive conductive columns. When the power management chip and the load are required to be on different sides of the package substrate, an odd number of the three-dimensional vertical inductors are obtained, such as Figure 11 The three-dimensional vertical inductor device provided by the present invention is applied on different sides of the PMIC and the load. In addition to embedding the magnetic core inductor structure on the same package substrate, a capacitor unit area is also set at the same time. The capacitor is constructed by screen printing, electroplating or embedding. The three-dimensional vertical inductor can be located on the top, middle and bottom layers of the package substrate. Figure 11 The three-dimensional vertical inductor in the package substrate provided by the present invention is located in the middle layer of the package substrate. Multilayer boards are pressed on the upper and lower sides of the inductor and are connected with multilayer wires. The metal layers can be connected through non-inductive interconnected conductive columns.

Claims

1. A three-dimensional vertical inductor device, characterized in that: It includes a packaging substrate, a composite magnetic core, a vertical inductor column, a horizontal conductor and an interconnected conductive column; The packaging substrate comprises an upper packaging substrate, a core having a blind groove and a lower packaging substrate; The composite magnetic core is embedded in the blind slot; The composite magnetic core comprises a plurality of insulating dielectric layers and magnetic layers alternately stacked in a vertical direction; The composite magnetic core is provided with a plurality of vertical inductor columns; the vertical inductor columns include conductive columns and vertical dielectric layers provided on the periphery of the conductive columns for preventing the conductive columns from contacting the magnetic layer; A plurality of interconnected conductive pillars are provided outside the composite magnetic core area; The conductive pillars are in contact with the horizontal conductor above or below; and the conductive pillars are electrically connected to each other through the horizontal conductor.

2. The three-dimensional vertical inductor device according to claim 1, wherein: The upper packaging substrate and the lower packaging substrate have multiple layers.

3. The three-dimensional vertical inductor device according to claim 2, wherein: The upper packaging substrate and the lower packaging substrate are connected through the interconnecting conductive pillars.

4. The three-dimensional vertical inductor device according to claim 1, wherein: There is at least one blind slot and the composite magnetic core is equal in number.

5. The three-dimensional vertical inductor device according to claim 1, wherein: Each vertical inductor column has a plurality of conductive columns, and adjacent conductive columns are insulated from each other.

6. The three-dimensional vertical inductor device according to claim 1, wherein: When the conductive column and the horizontal conductor are connected to form a conductive path, the three-dimensional vertical inductor is a single inductor; when the conductive column and the horizontal conductor are connected to form two or more conductive paths, the three-dimensional vertical inductor is a multi-phase inductor.

7. A method for preparing a three-dimensional vertical inductor device, characterized in that: The method is used to implement the three-dimensional vertical inductor device according to claim 1, comprising the following steps: S1. preparing the composite magnetic core and the packaging substrate; S2. Embed the composite magnetic core into the blind slot, and bond the upper packaging substrate, the core, and the lower packaging substrate to form an integral structure through a hot pressing process, with the gap between the composite magnetic core and the packaging substrate being filled with organic matter; S3, preparing the vertical inductor column, including: S31, drilling a first through hole in a vertical direction within the composite magnetic core region of the overall structure and filling the first through hole with insulating colloid to form the vertical dielectric layer; S32, drilling again to form a second through hole in a direction perpendicular to the center of the insulating colloid and outside the composite magnetic core region of the overall structure, and filling the second through hole with conductive material to form the conductive pillar and the interconnected conductive pillar, respectively; the diameter of the first through hole is larger than the diameter of the second through hole; S4. Prepare the horizontal conductor; perform patterning on the conductive surfaces of the upper packaging substrate and the lower packaging substrate so that the tops or bottoms of the plurality of conductive pillars are interconnected to form the horizontal conductor and the horizontal conductive path.

8. A method for preparing a three-dimensional vertical inductor device, characterized in that: The method is used to implement the three-dimensional vertical inductor device according to claim 1, comprising the following steps: S1. preparing the composite magnetic core and the packaging substrate; S2. Preparing the vertical inductor column and the interconnected conductive column, including: S21, while forming a through groove on the surface of the composite magnetic core, drilling a third through hole in a vertical direction outside the composite magnetic core; filling the through groove and the third through hole with insulating colloid respectively to form the vertical dielectric layer; S22, bonding the upper packaging substrate, the composite magnetic core, and the lower packaging substrate to form a combined structure through a hot pressing process; S23, drilling a fourth through hole again in a direction perpendicular to the center of the third through hole of the combined structure, and filling the fourth through hole with conductive material to form the vertical inductor column; the diameter of the third through hole is larger than the diameter of the fourth through hole; simultaneously, drilling a hole in the insulating colloid at the through slot position and filling it with conductive material to form the interconnected conductive column; the upper packaging substrate and the lower packaging substrate are connected via the interconnected conductive column; S3. Prepare the horizontal conductor; perform patterning on the conductive surfaces of the upper packaging substrate and the lower packaging substrate to form the horizontal conductor and the horizontal conductive path, so that the tops or bottoms of the multiple conductive columns are interconnected to form a series and parallel structure of multiple vertical inductor columns.

9. The method for preparing a three-dimensional vertical inductor device according to claim 7 or 8, characterized in that: The preparation of the composite magnetic core comprises: S11, preparing the magnetic layer and the insulating dielectric layer; the magnetic layer can be prepared separately or directly on the insulating dielectric layer; S12. Alternately stacking the magnetic layers and the insulating medium layers multiple times to form the composite magnetic core.

10. The method for preparing a three-dimensional vertical inductor device according to claim 7 or 8, characterized in that: Also includes: The inductance value of the three-dimensional vertical inductor is adjusted by adjusting the material type and thickness of the magnetic layer, the thickness of the insulating dielectric layer, the number of alternating stacking, and the diameter of the through-hole filled with insulating colloid in the vertical direction of the composite magnetic core; Adjusting the number of phases and the inductance of each phase of the three-dimensional vertical inductor device by adjusting the connection mode and quantity in the graphic; The coupling coefficient between the multi-phase inductors is adjusted by adjusting the distance between the drilled holes.

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