Inductor structure

Abstract

An inductor structure is characterized in that an inductor body and a magnetic core structure with a plurality of through holes are embedded in an insulator, so that the binding force between the magnetic core structure and the insulator is improved through the through holes, and the inductor structure can avoid the stripping phenomenon.

Description

Technical Field

[0001] The invention relates to an inductor structure, in particular to an inductor structure with a magnetic core. Background Art

[0002] With the booming development of the electronics industry and the evolution of packaging technology, the size or volume of semiconductor packages has been continuously reduced, so that the semiconductor packages can be thin and light. The substrates of semiconductor packages currently used in electronic products, such as mobile phone chip carriers, lens module circuit boards or coil boards, etc., are designed with magnetic cores to increase the magnetic flux of the substrate, thereby improving the performance of the substrate.

[0003] Figure 1A is a cross-sectional schematic diagram of a conventional coil substrate 1a with a horizontal winding structure, and Figure 1B FIG. 1 is a cross-sectional schematic diagram of an existing coil substrate 1b having a vertical winding structure. Figure 1A and Figure 1B As shown, the conventional coil substrate 1a, 1b comprises: a packaging layer 10a, 10b, a coil structure 11a, 11b and a magnetic core 12a, 12b embedded in the packaging layer 10a, 10b, and a plurality of electrode pads 13a, 13b connecting the coil structure 11a, 11b and providing external electrical connection.

[0004] Furthermore, the coil structure 11a, 11b surrounds a central axis C to be embedded in the packaging layer 10a, 10b, and the magnetic core 12a, 12b is embedded in the packaging layer 10a, 10b along the central axis C, so that the coil structure 11a, 11b is disposed in the packaging layer 10a, 10b around the magnetic core 12a, 12b.

[0005] However, in the prior art, due to the poor bonding between the magnetic core 12a, 12b and the packaging layer 10a, 10b in the existing coil substrates 1a, 1b, the magnetic core 12a, 12b and the packaging layer 10a, 10b are peeled off, which greatly reduces the process yield of the existing coil substrates 1a, 1b.

[0006] Therefore, how to overcome the above-mentioned problems of the prior art has become a topic that needs to be overcome urgently in the current industry. Summary of the invention

[0007] An object of the present invention is to provide an inductor structure to solve at least one of the above problems.

[0008] In view of the problems of the prior art, the present invention provides an inductor structure, comprising: an insulator having a first side and a second side opposite to each other; an inductor body, which is a spiral coil buried in the insulator; and a magnetic core structure having a plurality of through holes, buried in the spiral coil of the inductor body in the insulator, wherein the plurality of through holes extend along the connecting line direction between the first side and the second side of the insulator and penetrate the magnetic core structure.

[0009] In the aforementioned inductor structure, the projection outline of the magnetic core structure on the first side and / or the second side of the insulator is rectangular, circular, symmetrical polygonal or irregular polygonal.

[0010] In the aforementioned inductor structure, the magnetic core structure is in the form of multiple layers stacked at intervals, and the layers are not electrically connected to each other.

[0011] In the aforementioned inductor structure, the inductor body is a spiral coil that is wound horizontally or vertically.

[0012] In the aforementioned inductor structure, the inductor body includes a plurality of inductor circuit layers spaced apart from each other and a conductor connecting adjacent inductor circuit layers, and two outer ends of the plurality of inductor circuit layers respectively have external electrical contacts.

[0013] The aforementioned inductor structure further includes a first conductive column and a second conductive column, which are buried in the insulator so that the first conductive column and the second conductive column are respectively connected to the two external electrical contacts, wherein at least one end of the first conductive column is exposed to a surface of the first side or the second side of the insulator, and at least one end of the second conductive column is exposed to a surface of the first side or the second side of the insulator.

[0014] In the aforementioned inductor structure, the plurality of inductor circuit layers are in the form of a single-strand spiral coil.

[0015] In the aforementioned inductor structure, the plurality of inductor circuit layers are in the form of multi-strand spiral coils.

[0016] In the aforementioned inductor structure, the ends of the plurality of inductor circuit layers are connected.

[0017] In the aforementioned inductor structure, the ends of the plurality of inductor circuit layers are separated.

[0018] As can be seen from the above, the inductor structure of the present invention mainly forms multiple through-holes in the magnetic core structure. Therefore, compared with the prior art, the present invention improves the bonding force between the magnetic core structure and the insulator by having a magnetic core structure with multiple through-holes, thereby preventing the inductor structure from peeling off. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1AIt is a cross-sectional schematic diagram of a conventional coil substrate with a horizontal winding structure.

[0020] Figure 1B It is a cross-sectional schematic diagram of a conventional coil substrate with a vertical winding structure.

[0021] Figure 2 FIG. 4 is a cross-sectional schematic diagram of a first embodiment of an inductor structure of the present invention.

[0022] Figure 2A , Figure 2B and Figure 2B-1 for Figure 2 A top plan view of the inductor circuit layer and the magnetic core structure.

[0023] Figure 2C for Figure 2 A cross-sectional schematic diagram of another embodiment of the present invention.

[0024] Figure 2D-1 to Figure 2D-4 The projection profile of the magnetic core structure of the present invention on the first side of the insulator.

[0025] Figure 3 FIG. 4 is a cross-sectional diagram of a second embodiment of an inductor structure of the present invention.

[0026] Figure 3A , Figure 3B and Figure 3B-1 for Figure 3 A top plan view of the inductor circuit layer and the magnetic core structure.

[0027] Figure 3C for Figure 3 A cross-sectional schematic diagram of another embodiment of the present invention.

[0028] The reference numerals are as follows:

[0029] 1a, 1b Existing coil substrate

[0030] 10a, 10b packaging layer

[0031] 11a, 11b coil structure

[0032] 12a,12b core

[0033] 13a, 13b electrode pads

[0034] 2,3 Inductor Structure

[0035] 20,30 Insulator

[0036] 20a,30a first side

[0037] 20b,30b Second side

[0038] 21,31 Inductor body

[0039] 21a, 21b, 21c, 22d, 31a, 31b inductor circuit layer

[0040] 210a, 210b, 310a, 310b are external electrical contacts

[0041] 22,32 core structure

[0042] 22a, 32a first surface

[0043] 22b, 32b Second surface

[0044] 220,320 perforations

[0045] 221,222,223,321,322,323 magnetic conductive layer

[0046] 23a, 23b, 33a, 33b, 33c Conductor

[0047] 24a, 34a first conductive column

[0048] 24b, 34b second conductive column

[0049] 25a, 35a first electrical contact pad

[0050] 25b, 35b second electrical contact pad

[0051] 26,36 surface treatment layers

[0052] C Center axis

[0053] O,O' coil axis

[0054] T1, T1', T2, T2' end DETAILED DESCRIPTION

[0055] The following describes the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0056] It should be noted that the structures, proportions, sizes, etc. shown in the attached drawings of this specification are only used to match the contents disclosed in the specification for the understanding and reading of those skilled in the art, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be produced by the present invention, should still fall within the scope of the technical contents disclosed in the present invention. At the same time, the terms such as "on", "first", "second" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical contents.

[0057] Figure 2 FIG. 2 is a cross-sectional diagram of a first embodiment of an inductor structure 2 of the present invention.

[0058] like Figure 2 As shown, the inductor structure 2 is a horizontal winding structure and includes an insulator 20, an inductor body 21 surrounding a coil axis O and buried in the insulator 20, and a magnetic core structure 22 along the coil axis O and buried in the insulator 20, so that the inductor body 21 is arranged around the magnetic core structure 22.

[0059] The insulator 20 has a first side 20a and a second side 20b opposite to each other. In this embodiment, the insulator 20 is a dielectric material, such as ABF (Ajinomoto Build-up Film), photosensitive resin, polyimide (PI), bismaleimide triazine (BT), FR5 prepreg (PP), molding compound, epoxy molding compound (EMC) or other suitable materials. The preferred material of the insulator 20 is PI, ABF or EMC, which are easy to process circuits.

[0060] The inductor body 21 includes a plurality of inductor circuit layers 21a, 21b, 21c, 22d spaced apart from each other, and at least one conductor 23a, 23b connecting adjacent inductor circuit layers 21a, 21b, 21c, 22d, wherein the inductor body 21 is a spiral coil made of copper, and the number of strands of the coil can be designed according to requirements, such as Figure 2A As shown, the inductor circuit layer 21a in the inductor body 21 is a single-strand spiral coil; and Figure 2B and 2B-1As shown, the inductor circuit layer 21a in the inductor body 21 is a multi-strand (such as two-strand) spiral coil, wherein one end T1 of the inductor circuit layer 21a connected to the next inductor circuit layer 21b can be in a connection state (such as Figure 2B ), or one end T1' may be separated without connecting the two helical coils (as shown in FIG. Figure 2B-1 In detail, the design of a single-strand spiral coil is generally better for use in circuits with frequencies higher than 2 MHz, while the design of a multi-strand spiral coil is generally better for use in circuits with frequencies lower than 2 MHz.

[0061] In this embodiment, the two external electrical contacts 210a, 210b of the inductor body 21 are respectively located at the outer ends of the two inductor circuit layers 21a, 21c close to the first side 20a and the second side 20b, so as to serve as an input port and an output port. For example, a first conductive column 24a and a second conductive column 24b are formed in the insulator 20, so that the first conductive column 24a is connected to the second side 20b of the insulator 20 and connects a pair of external electrical contacts 210a in the inductor circuit layer 21a; and the second conductive column 24b is connected to the second side 20b of the insulator 20 and connects another external electrical contact 210b in another inductor circuit layer 21c.

[0062] Furthermore, one end surface of the first conductive column 24a is connected to a first electrical contact pad 25a disposed on the second side 20b of the insulator 20, and one end surface of the second conductive column 24b is connected to a second electrical contact pad 25b disposed on the second side 20b of the insulator 20, so that the first and second electrical contact pads 25a, 25b can be used to connect other electronic components.

[0063] In addition, a surface treatment layer 26 and / or solder material can be formed on the first electrical contact pad 25a and the second electrical contact pad 25b to facilitate the connection of other electronic components, wherein the material forming the surface treatment layer 26 is nickel / gold (Ni / Au), nickel / palladium / gold (Ni / Pd / Au) or organic solderability preservative (OSP), etc.

[0064] The magnetic core structure 22 has a first surface 22a and a second surface 22b opposite to each other, and a plurality of through holes 220 penetrating the first surface 22a and the second surface 22b. That is, the plurality of through holes 220 extend along the connecting line between the first side 20a and the second side 20b of the insulator 20.

[0065] In this embodiment, the magnetic core structure 22 is a magnetic conductive material, such as at least one of iron (Fe), nickel (Ni), cobalt (Co), manganese (Mn), zinc (Zn) or a combination thereof.

[0066] Furthermore, the magnetic core structure 22 is buried in the insulator 20 along the coil axis O, and the inductor body 21 surrounds the magnetic core structure 22. The multiple through holes 220 of the magnetic core structure 22 are filled with the material of the insulator 20. The multiple through holes 220 strengthen the bonding force between the magnetic core structure 22 and the insulator 20, thereby avoiding peeling between the insulator 20 and the magnetic core structure 22.

[0067] In one embodiment, the magnetic core structure 22 may be a single magnetic conductive layer 221 (eg Figure 2 ), or by a plurality of magnetic conductive layers 222, 223 (such as Figure 2C For example, the magnetic conductive layers 221, 222, 223 can be formed by a patterning process to obtain the magnetic core structure 22, and the plurality of magnetic conductive layers 221, 222, 223 are not electrically connected to each other.

[0068] In one embodiment, the magnetic core structure 22 is rectangular in shape, as shown by the profile of the first surface 22a of the magnetic core structure 22, that is, the projection profile on the first side 20a. Figure 2A As shown), rectangle (as Figure 2D-1 As shown), trapezoidal (as Figure 2D-2 The magnetic core structure 22 is symmetrical polygonal or irregular polygonal (such as Figure 2D-3 or, the outline of the magnetic core structure 22 is circular (as shown); Figure 2D-4 Therefore, the magnetic core structure 22 can improve the bonding force between it and the insulator 30 and meet various design requirements through different shapes and contours.

[0069] Figure 3 FIG. 3 is a cross-sectional view of a second embodiment of the inductor structure 3 of the present invention. Furthermore, the second embodiment is substantially the same as the first embodiment, so the same parts are not repeated here.

[0070] like Figure 3 As shown, the inductor structure 3 is a vertical winding structure and includes an insulator 30, an inductor body 31 surrounding a coil axis O' and buried in the insulator 30, and a magnetic core structure 32 along the coil axis O' and buried in the insulator 30, so that the inductor body 31 is arranged around the magnetic core structure 32.

[0071] The inductor body 31 includes two inductor circuit layers 31a, 31b, and at least one conductor 33a, 33b, 33c (such as Figure 3A As shown), the inductor body 31 is a spiral coil made of copper, and the number of strands of the coil can be designed according to the requirements, such as Figure 3AAs shown, the inductor circuit layer 31a in the inductor body 31 is a single-strand spiral coil; and Figure 3B and 3B-1 As shown, the inductor circuit layer 31a in the inductor body 31 is a multi-strand (such as two-strand) spiral coil, wherein the multiple ends T2 of the inductor circuit layer 31a connected to the next inductor circuit layer 31b can be in a connection state (such as Figure 3B ), or the multiple ends T2' may be separated (as shown Figure 3B-1 shown).

[0072] In this embodiment, the two pairs of external electrical contacts 310a, 310b of the inductor body 31 are respectively located at the outer ends of the two outermost inductor circuit layers 31a, 31b to serve as input ports and output ports. For example, a first conductive column 34a and a second conductive column 34b are embedded in the insulator 30, so that the first conductive column 34a is connected to the second side 30b of the insulator 30 and connected to a pair of external electrical contacts 310a of the inductor circuit layer 31a; and the second conductive column 34b is connected to the second side 30b of the insulator 30 and connected to another external electrical contact 310b of another inductor circuit layer 31b.

[0073] Furthermore, one end surface of the first conductive column 34a is connected to a first electrical contact pad 35a disposed on the second side 30b of the insulator 30, and one end surface of the second conductive column 34b is connected to a second electrical contact pad 35b disposed on the second side 30b of the insulator 30, so that the first electrical contact pad 35a and the second electrical contact pad 35b are used to connect other electronic components. In addition, a surface treatment layer 36 and / or solder material can be formed on the first electrical contact pad 35a and the second electrical contact pad 35b to facilitate the connection of other electronic components.

[0074] The magnetic core structure 32 has a first surface 32a and a second surface 32b opposite to each other, and a plurality of through holes 320 penetrating the first surface 32a and the second surface 32b, that is, the plurality of through holes 320 extend along the connecting line direction between the first side 30a and the second side 30b of the insulator 30. Furthermore, the magnetic core structure 32 is embedded in the insulator 30 along the coil axis O', and the inductor body 31 surrounds the magnetic core structure 32, and the bonding force between the magnetic core structure 32 and the insulator 30 is strengthened by the plurality of through holes 320. For example, the plurality of through holes 320 are filled with the material of the insulator 30, thereby improving the bonding force between the two, thereby preventing the insulator 30 and the magnetic core structure 32 from peeling off.

[0075] In one embodiment, the magnetic core structure 32 may be a single magnetic conductive layer 321 (eg Figure 3 ), or by a plurality of magnetic conductive layers 322, 323 (such as Figure 3C For example, the magnetic conductive layers 321, 322, 323 can be formed by a patterning process to obtain the magnetic core structure 32, and the plurality of magnetic conductive layers 322, 323 are not electrically connected to each other. Furthermore, from the outline presented by the first surface 32a of the magnetic core structure 32, it can be seen that the magnetic core structure 32 is rectangular. For example, a square, a rectangle (such as Figure 2D-1 As shown), trapezoidal (as Figure 2D-2 The outline of the magnetic core structure 22 is a symmetrical polygonal shape or an irregular polygonal shape (such as Figure 2D-3 or, the outline of the magnetic core structure 22 is circular (as shown); Figure 2D-4 Therefore, the magnetic core structure 22 can enhance the bonding force between the magnetic core structure 22 and the insulator 30 through different shapes and contours.

[0076] In summary, the inductor structures 2, 3 of the present invention can be manufactured by a processing method of a circuit board (PCB) or a carrier board to form an inductor body, a magnetic core structure and a conductive column including multiple inductor circuit layers and conductors, which can be easily mass-produced on a large scale. The patterned layer-building circuit method of a coreless embodiment is used to form the magnetic conductive material by electroplating or deposition, so that the precision of the magnetic core structure 22, 32 is extremely well controlled, thereby forming multiple through-holes in the magnetic core structure 22, 32. Therefore, compared with the prior art, the present invention uses a magnetic core structure 22, 32 with multiple through-holes to enhance the bonding force between the magnetic core structure 22, 32 and the insulator 20, 30, thereby avoiding the peeling phenomenon of the inductor structure 2, 3.

[0077] Furthermore, the present invention further enhances the bonding force between the magnetic core structures 22 , 32 and the insulators 20 , 30 by forming the surface profile of the magnetic core structures 22 , 32 into a polygonal shape.

[0078] The above embodiments are only used to illustrate the principles and effects of the present invention, and are not used to limit the present invention. Those skilled in the art may modify the above embodiments without violating the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be as listed in the claims.

Claims

1. An inductor structure, comprising: an insulator having opposing first and second sides; The inductor body is a spiral coil buried in the insulator; as well as A magnetic core structure with a plurality of through holes is embedded in the spiral coil of the inductor body in the insulator, wherein the plurality of through holes extend along the connecting line direction between the first side and the second side of the insulator and penetrate the magnetic core structure.

2. The inductor structure according to claim 1, wherein: The projection profile of the magnetic core structure on the first side and / or the second side of the insulator is rectangular, circular, symmetrical polygonal or irregular polygonal.

3. The inductor structure according to claim 1, wherein: The magnetic core structure is in the form of multiple layers stacked at intervals, and the layers are not electrically connected to each other.

4. The inductor structure according to claim 1, wherein: The inductor body is a horizontally wound or longitudinally wound spiral coil.

5. The inductor structure according to claim 1, wherein: The inductor body comprises a plurality of inductor circuit layers spaced from each other and a conductor connecting adjacent inductor circuit layers, and two outer ends of the plurality of inductor circuit layers respectively have external electrical contacts.

6. The inductor structure according to claim 5, wherein: The structure also includes a first conductive column and a second conductive column, and is buried in the insulator so that the first conductive column and the second conductive column are respectively connected to the two external electrical contacts, wherein at least one end of the first conductive column is exposed to a surface of the first side or the second side of the insulator, and at least one end of the second conductive column is exposed to a surface of the first side or the second side of the insulator.

7. The inductor structure according to claim 1, wherein: The plurality of inductor circuit layers are in the form of single-strand spiral coils.

8. The inductor structure according to claim 1, wherein: The plurality of inductor circuit layers are in the form of a plurality of spiral coils.

9. The inductor structure according to claim 8, wherein: The ends of the plurality of inductor circuit layers are in a connected state.

10. The inductor structure according to claim 8, wherein: The ends of the plurality of inductor circuit layers are in a separated state.

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