CN115458275B

CN115458275B - Inductor and preparation method thereof, filter

Info

Publication number: CN115458275B
Application number: CN202211113792.4A
Authority: CN
Inventors: 曹雪; 冯昱霖; 李月; 肖月磊; 吴艺凡; 李慧颖; 安齐昌; 李必奇
Original assignee: BOE Technology Group Co Ltd; Beijing BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Beijing BOE Optoelectronics Technology Co Ltd
Priority date: 2022-09-14
Filing date: 2022-09-14
Publication date: 2025-03-21
Anticipated expiration: 2042-09-14
Also published as: CN115458275A

Abstract

The present disclosure provides an inductor and a preparation method thereof, and a filter, which belong to the technical field of passive devices. The inductor disclosed in the present disclosure comprises: a dielectric substrate having a connecting via hole penetrating along the thickness direction thereof; the dielectric substrate comprising a first surface and a second surface arranged opposite to each other along the thickness direction thereof; a first conductive structure arranged on the first surface; a second conductive structure arranged on the second surface, and the first conductive structure and the second conductive structure are electrically connected through a connecting electrode located in the connecting via hole to form a coil structure of the inductor; wherein at least one of the first conductive structure and the second conductive structure has a hollow pattern.

Description

Inductance, preparation method thereof and filter

Technical Field

The disclosure belongs to the technical field of passive devices, and particularly relates to an inductor, a preparation method thereof and a filter.

Background

In the current generation, the consumer electronics industry is developing gradually, mobile communication terminals represented by mobile phones, particularly 5G mobile phones, are developing rapidly, the frequency bands of signals to be processed of the mobile phones are increasing, the number of required radio frequency chips is also increased, and the mode of obtaining the mobile phones favored by consumers is developing continuously towards miniaturization, light weight and long endurance. In the traditional mobile phone, a large number of discrete devices such as resistors, capacitors, inductors, filters and the like exist on a radio frequency PCB, and the discrete devices have the defects of large volume, high power consumption, multiple welding spots and large parasitic parameter variation, so that the future requirements are difficult to deal with. The radio frequency chips are mutually interconnected, matched and the like to be integrated passive devices with small area, high performance and good consistency. The integrated passive devices currently on the market are mainly based on Si (silicon) substrates and GaAs (gallium arsenide) substrates. The Si-based integrated passive device has the advantage of low price, but Si has trace impurities (poor insulativity) to cause higher microwave loss and general performance, and the GaAs-based integrated passive device has the advantage of excellent performance but high price.

Disclosure of Invention

The invention aims to at least solve one of the technical problems in the prior art, and provides an inductor, a preparation method thereof and a filter.

In a first aspect, embodiments of the present disclosure provide an inductor, comprising:

The dielectric substrate is provided with a connecting via hole penetrating along the thickness direction of the dielectric substrate, and comprises a first surface and a second surface which are oppositely arranged along the thickness direction of the dielectric substrate;

A first conductive structure disposed on the first surface;

a second conductive structure disposed on the second surface, wherein the first conductive structure and the second conductive structure are electrically connected by a connection electrode disposed in the connection via hole to form a coil structure of the inductor,

At least one of the first conductive structure and the second conductive structure is provided with a hollowed-out pattern.

When the first conductive structure is provided with the hollowed-out pattern, the hollowed-out pattern comprises a first opening extending along the extending direction of the first conductive structure;

When the second conductive structure is provided with the hollowed-out pattern, the hollowed-out pattern comprises a second opening extending along the extending direction of the second conductive structure.

When the first conductive structure is provided with the hollowed-out pattern, the first opening is provided with a first edge and a second edge which are oppositely arranged along the length direction of the first conductive structure, and orthographic projections of the first edge and the second edge on the plane where the first surface is located respectively fall on the outline of orthographic projections of the first edge and the second edge on the plane where the first surface is located;

When the second conductive structure is provided with the hollowed-out pattern, the second opening is provided with a third side and a fourth side which are oppositely arranged along the length direction of the second conductive structure, and orthographic projections of the third side and the fourth side on the plane where the first surface is located respectively fall on the outline of the plane where the two connecting through holes are located on the first surface.

When the first conductive structure is provided with the hollowed-out pattern, for one first conductive structure and covering two connection through holes with the first conductive structure, orthographic projection of the first opening of the first conductive structure on the plane where the first surface is located is not overlapped with orthographic projection of the two connection through holes on the plane where the first surface is located;

when the second conductive structure is provided with the hollowed pattern, the hollowed pattern comprises a second opening extending along the extending direction of the second conductive structure, and for one second conductive structure and two connecting through holes covered with the second conductive structure, orthographic projection of the second opening of the second conductive structure on the plane where the first surface is located is not overlapped with orthographic projection of the two connecting through holes on the plane where the first surface is located.

When the first conductive structure is provided with the hollowed-out pattern, the first opening comprises a fifth side and a sixth side which extend along the length direction of the first connection structure and are oppositely arranged, wherein the fifth side and the sixth side are straight line segments or folded line segments;

When the second conductive structure is provided with the hollowed-out pattern, the second opening comprises a seventh side and an eighth side which extend along the length direction of the second connection structure and are oppositely arranged, and the seventh side and the eighth side are straight line segments or folded line segments.

When the first conductive structure has the hollowed-out pattern, the center of orthographic projection of the outer contour of the first conductive structure on the plane where the first surface is located is a first center, the center of orthographic projection of the first opening on the plane where the first surface is located is a second center, and the first center and the second center are overlapped;

When the second conductive structure has the hollowed-out pattern, the center of orthographic projection of the outer contour of the second conductive structure on the plane where the first surface is located is a third center, the center of orthographic projection of the first opening on the plane where the first surface is located is a fourth center, and the third center and the fourth center are overlapped.

When the first conductive structure is provided with the hollowed-out pattern, the hollowed-out pattern comprises a plurality of first openings, the first openings extend along the length direction of the first conductive structure, and the width directions of the first conductive structures are arranged side by side;

When the second conductive structure is provided with the hollowed-out pattern, the hollowed-out pattern comprises a plurality of second openings, the second openings extend along the length direction of the second conductive structure, and the width directions of the second conductive structures are arranged side by side.

Wherein the film thickness of the first conductive structure and the second conductive structure is larger than 1 μm.

When the first conductive structure is provided with the hollowed-out pattern, the width of the first opening is larger than 10 mu m, and when the second conductive structure is provided with the hollowed-out pattern, the second opening is larger than 10 mu m.

In a second aspect, an embodiment of the present disclosure provides a method for manufacturing an inductor, including:

Providing a dielectric substrate, wherein the dielectric substrate is provided with a connecting via hole penetrating along the thickness direction of the dielectric substrate, and the dielectric substrate comprises a first surface and a second surface which are oppositely arranged along the thickness direction of the dielectric substrate;

A connecting electrode is formed in the connecting via hole of the dielectric substrate, a first conductive structure is formed on the first surface, a second conductive structure is formed on the second surface, the first conductive structure and the second conductive structure are electrically connected through the connecting electrode in the connecting via hole to form a coil structure of the inductor,

The first conductive structure is provided with a hollowed-out pattern, and/or the second conductive structure is provided with a hollowed-out pattern.

The preparation method of the inductor further comprises the steps of forming a first protection layer on one side, away from the first surface, of the first conductive structure, and forming a second protection layer on one side, away from the second surface, of the second conductive structure.

In a third aspect, embodiments of the present disclosure provide a filter comprising an inductor as described in any one of the above.

Drawings

Fig. 1 is a schematic diagram of an exemplary inductor.

Fig. 2 is a cross-sectional view of an exemplary inductor.

Fig. 3 is a schematic diagram of an inductance of an embodiment of the disclosure.

Fig. 4 is a parametric identification diagram of the inductance principle of a first conductive structure of the inductor shown in fig. 1.

Fig. 5 is a parametric identification diagram of the inductance principle of a first conductive structure of the inductor shown in fig. 2.

Fig. 6 is another inductance schematic diagram of an embodiment of the present disclosure.

Fig. 7 is another inductance schematic diagram of an embodiment of the present disclosure.

Fig. 8 is another inductance schematic diagram of an embodiment of the present disclosure.

Fig. 9 is another inductance schematic diagram of an embodiment of the present disclosure.

Fig. 10 is a circuit diagram of a filter of an embodiment of the present disclosure.

Detailed Description

The present invention will be described in further detail below with reference to the drawings and detailed description for the purpose of better understanding of the technical solution of the present invention to those skilled in the art.

Unless defined otherwise, technical or scientific terms used in this disclosure should be given the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," and the like, as used in this disclosure, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a," "an," or "the" and similar terms do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.

In a first aspect, an embodiment of the present disclosure provides an inductor, which is a three-dimensional inductor structure, and includes a dielectric substrate 10, a connection electrode, a first conductive structure 21 and a second conductive structure 22, where the dielectric substrate 10 has a plurality of connection vias 11 penetrating along a thickness direction thereof, and each connection via 11 is filled with the connection electrode. The dielectric substrate 10 includes a first surface (upper surface) and a second surface (lower surface) disposed opposite to each other in a thickness direction thereof, the first conductive structure 21 is disposed on the first surface of the dielectric, and the second conductive structure 22 is disposed on the second surface of the dielectric substrate 10, at which time the first conductive structure 21 is electrically connected to the second conductive structure 22 through a connection electrode located in the connection via 11, forming a coil structure of the inductor.

Specifically, referring to fig. 1 and 2, fig. 1 is a top view of an exemplary inductor, fig. 2 is a cross-sectional view of an exemplary inductor, each of the first conductive structures 21 of the inductor extends in a first direction and is disposed side by side in a second direction, and each of the second conductive structures 22 of the inductor extends in a third direction and is disposed side by side in the second direction. The connection vias 11 on the dielectric substrate 10 are divided into two groups side by side along the first direction, each group including a plurality of the connection vias arranged side by side along the second direction. In the embodiment of the disclosure, the first direction and the second direction are perpendicular to each other, and the first direction and the third direction intersect and are not perpendicular to each other. Of course, the extending directions of the first conductive structure 21 and the second conductive structure 22 may also be interchanged, which are all within the protection scope of the embodiments of the present disclosure. In addition, in the present embodiment, the inductance is described by taking the inductance including N first conductive structures 21 and N-1 second conductive structures 22 as an example, where N is equal to or greater than 2, and N is an integer. The first and second ends of the first conductive structure 21 respectively overlap at least partially with the orthographic projection of one of the connection vias 11 on the dielectric substrate 10. And the first end and the second end of one first conductive structure 21 correspond to different connection via holes 11, that is, one first conductive structure 21 at least partially overlaps with the orthographic projection of two connection via holes 11 on the dielectric substrate 10. At this time, the first end of the ith second conductive structure 22 of the inductor is connected to the first end of the ith first conductive structure 21 and the second end of the (i+1) th first conductive structure 21 by the connection electrode 11 in the connection via 11 to form an inductor coil, wherein i is greater than or equal to 1 and less than or equal to N-1, and i is an integer.

Referring to fig. 3, in the embodiment of the present disclosure, at least one of the first conductive structure 21 and the second conductive structure 22 has a hollowed-out pattern. In the same way, when the second conductive structure 22 has the hollowed pattern, the stress of the second conductive pattern to the dielectric substrate 10 can be effectively reduced, and the risk of warping of the dielectric substrate 10 can be reduced.

In some examples, when the first conductive structure 21 has a hollowed-out pattern, the hollowed-out pattern has at least one first opening 210 extending along a length direction of the first conductive structure 21. In fig. 3, only the first conductive structure 21 has a first opening 210. In this case, any one of the first conductive structures 21 is equivalent to a plurality of first sub-structures connected in parallel, and the inductance between the first sub-structures of the first conductive structures 21 and the inductance of the first sub-structures of the first conductive structures 21 disposed adjacently increase the inductance value of the inductance, thereby improving the inductance density. Similarly, when the second conductive structure 22 has a hollowed pattern, the hollowed pattern has at least one second opening 220 extending along the length direction of the second conductive structure 22. In fig. 6, only the second conductive structure 22 has a second opening 220. In this case, any one of the second conductive structures 22 is equivalent to a plurality of second sub-structures connected in parallel, and the inductance between the second sub-structures of the second conductive structures 22 and the inductance of the second sub-structures of the second conductive structures 22 disposed adjacently increase the inductance value of the inductance, thereby improving the inductance density.

The specific principle of increasing the inductance value of the inductor by using the above-described structure will be described below. The inductance of the first conductive structures 21 is illustrated, wherein the first conductive structures 21 have a hollowed pattern, the hollowed pattern is a first opening 210 extending along the length direction of the first conductive structures 21, and the number of the first openings 210 is one, and at this time, each first conductive structure 21 is divided into two parallel first sub-structures by the first opening 210.

The inductance of any one first conductive structure 21 comprises three parts, namely self inductance, mutual inductance in the same direction between adjacent first conductive structures 21 and mutual inductance in different directions between second conductive structures 22 arranged opposite to the first conductive structures, wherein the inductance value of the self inductance of the first conductive structures 21 can be estimated by using a formula 1, the inductance value of the mutual inductance can be estimated by using a formula 2, the inductance value of the mutual inductance can be estimated by using the length and the width of the first conductive structures 21, the width is reduced in unit length, and the mutual inductance is larger. In the calculation of the total inductance, the mutual inductance in the same direction is added into the self inductance, and the mutual inductance in the opposite direction is subtracted from the self inductance.

Total inductance of the trace = self inductance + co-inductance-anisotropic inductance.

As shown in fig. 4, the inductance l=la+mab-Mac of the first conductive structure 21a, la is the self inductance of a of the first conductive structure 21, mab is the mutual inductance between the first conductive structure 21a and the second conductive structure 22b, and Mac is the mutual inductance between the first conductive structure 21a and the first conductive structure 21 c.

Referring to fig. 5, for the first substructure a1 of the first conductive structure 21, the mutual inductance in the same direction is increased from Mab to ma1a2+ma1b1+ma1b2, and the inductance of a1 is greatly increased because the center distance between the first substructure a1 and the first substructure a2, the center distance between the first conductive structure 21a and the first conductive structure 21b in the existing inductance structure is smaller than the center distance between the first substructure a1 and the first substructure a 2. Of course, the total inductance value is reduced after the first substructure a1 and the inductance of the first substructure a2 are connected in parallel, but the inductance value of the inductance is still improved as a whole. Taking the first substructure with the line width of 80 μm, the width of the first opening 210 on the first conductive structure 21 is 20 μm, and the line length of the first conductive structure 21 is 200 μm as an example, the inductance of the first conductive structure 21 in the inductance structure shown in fig. 3 is calculated to be about 0.1nH, and the inductance of the first conductive structure 21 in the inductance structure shown in fig. 5 is calculated to be about 0.12nH, so that the inductance value is increased by 20%, and the inductance value is increased by different magnitudes according to the hollowing size.

In the embodiment of the disclosure, the first conductive structure 21 may be provided with a hollowed pattern, that is, the first conductive structure 21 has a first opening 210, the first opening 210 extends along the length direction of the first conductive structure 21, as shown in fig. 6, the second conductive structure 22 may be provided with a hollowed pattern, that is, the second conductive structure 22 has a second opening 220, and the second opening 220 extends along the length direction of the second conductive structure 22, as shown in fig. 7, where, of course, the first conductive structure 21 may be designed as the first conductive structure 21 with the first opening 210, and the second conductive structure 22 may be designed as the second conductive structure 22 with the second opening 220.

In some examples, when the first conductive structure 21 has a hollowed pattern, the front projection of the first opening 210 on the first surface of the dielectric substrate 10 has a first edge and a second edge that are disposed opposite to each other along the length direction of the first conductive structure 21. The orthographic projections of the first edge and the second edge on the plane of the first surface respectively fall on the outline of orthographic projections of the two connecting vias 11 on the plane of the first surface. Similarly, when the second conductive structure 22 has a hollowed pattern, the second opening 220 has a third side and a fourth side opposite to each other along the length direction of the second conductive structure 22, and orthographic projections of the third side and the fourth side on the plane where the first surface is located respectively fall on the outline of the plane where the two connection vias 11 are located.

In some examples, referring to fig. 8, considering the characteristics of the current portion in the connection via 11, the current is generally concentrated in the connection direction of the connection via 11 and the first conductive structure 21/second conductive structure 22, so when the first opening 210 is disposed on the first conductive structure 21, the position of the first opening 210 should avoid the connection via 11 where the connection electrode connected thereto is located, that is, a certain distance is between the first opening 210 and the connection via 11, that is, for one first conductive structure 21 and covering two connection vias 11 with the first conductive structure, the orthographic projection of the first opening 210 of the first conductive structure 21 on the plane where the first surface is located and the orthographic projection of the first opening 210 of the second conductive structure on the plane where the first surface is located do not overlap. Similarly, when the second opening 220 is disposed on the second conductive structure 22, the position of the second opening 220 should avoid the connection via 11 where the connection electrode connected thereto is located, that is, a certain distance is provided between the second opening 220 and the connection via 11, that is, for one second conductive structure 22 and the two connection vias 11 covered therewith, the orthographic projection of the second opening 220 of the second conductive structure 22 on the plane of the first surface is not overlapped with the orthographic projection of the two connection vias 11 on the plane of the first surface.

In some examples, when the number of the first openings 210 on the first conductive structure 21 is one, the center of the orthographic projection of the outer contour of the first conductive structure 21 on the plane of the first surface is a first center, the center of the orthographic projection of the first opening 210 on the plane of the first surface is a second center, and the first center and the second center are coincident. In this way, the inductance value of each first conductive structure 21 is made uniform. Similarly, when the number of the second openings 220 on the second conductive structure 22 is one, the center of the orthographic projection of the outer contour of the second conductive structure 22 on the plane where the first surface is located is the third center, the center of the orthographic projection of the first opening 210 on the plane where the first surface is located is the fourth center, and the third center and the fourth center are overlapped. In this way, the inductance value of each second conductive structure 22 is made uniform.

In some examples, when the first conductive structure 21 has a hollowed pattern, the number of the first openings 210 included in the hollowed pattern may be plural, and the plural first openings 210 extend along the length direction of the first conductive structure 21 and are uniformly arranged side by side. When the number of the first openings 210 is 2, the first conductive structure 21 is divided into 3 parallel first sub-structures, when the number of the first openings 210 is 3, the first conductive structure 21 is divided into 4 parallel first sub-structures, and when the number of the first openings 210 is 4, the first conductive structure 21 is divided into 5 parallel first sub-structures. Similarly, when the second conductive structure 22 has a hollowed pattern, the number of the second openings 220 included in the hollowed pattern may be plural, and the plurality of second openings 220 all extend along the length direction of the second conductive structure 22 and are uniformly arranged side by side. When the number of the second openings 220 is 2, the second conductive structure 22 is divided into 3 parallel second sub-structures, when the number of the second openings 220 is 3, the second conductive structure 22 is divided into 4 parallel second sub-structures, and when the number of the second openings 220 is 4, the second conductive structure 22 is divided into 5 parallel second sub-structures.

In some examples, the film thickness of both the first conductive structure 21 and the second conductive structure 22 is greater than 1 μm. When the first conductive structure 21 has the first opening 210, the width of the first opening 210 is greater than 10 μm, and when the second conductive structure 22 has the second opening 220, the width of the second opening 220 is greater than 10 μm. It should be noted that the width of the first opening 210 and the second opening 220 is related to the period of the connection via 11, and the period of the connection via 11 is about 100 μm in the embodiment of the present disclosure. The period of the connection via 11 refers to the center distance between the two connection vias 11 along the width direction of the first conductive structure 21.

In some examples, when the first conductive structure 21 has the first opening 210, when the first conductive structure 21 has the hollowed pattern, the first opening 210 includes a fifth side and a sixth side that extend along a length direction of the first connection structure and are disposed opposite to each other, where the fifth side and the sixth side are straight line segments as shown in fig. 3, or where the fifth side and the sixth side are folded line segments as shown in fig. 9. Similarly, when the second conductive structure 22 has a hollowed pattern, the second opening 220 includes a seventh side and an eighth side that extend along the length direction of the second connection structure and are disposed opposite to each other, and the seventh side and the eighth side are straight line segments or folded line segments. It should be noted that, in the embodiment of the present disclosure, the specific patterns of the fifth side and the sixth side of the first opening 210 are not limited, and similarly, the specific patterns of the seventh side and the eighth side of the second opening 220 are not limited.

In a second aspect, embodiments of the present disclosure provide a method for manufacturing an inductor, which may be used to manufacture any of the inductor structures described above. The preparation method of the inductor in the embodiment of the disclosure comprises the following steps:

A dielectric substrate 10 is provided, the dielectric substrate 10 has a connection via 11 penetrating in a thickness direction thereof, and the dielectric substrate 10 includes a first surface and a second surface disposed opposite to each other in the thickness direction thereof.

A connection electrode is formed in the connection via 11 of the dielectric substrate 10, a first conductive structure 21 is formed on the first surface, a second conductive structure 22 is formed on the second surface, and the first conductive structure 21 is electrically connected to the second conductive structure 22 through the connection electrode in the connection via 11 to form a coil structure of the inductor.

At least one of the first conductive structure 21 and the second conductive structure 22 formed in the embodiments of the present disclosure has a hollowed pattern. In the same way, when the second conductive structure 22 has the hollowed pattern, the stress of the second conductive pattern to the dielectric substrate 10 can be effectively reduced, and the risk of warping of the dielectric substrate 10 can be reduced.

In order to make the preparation method of the inductor in the embodiments of the present disclosure clearer, a specific example is described below. The preparation method of the inductor comprises the following steps:

s11, providing a dielectric substrate 10, wherein the dielectric substrate 10 comprises a first surface and a second surface which are oppositely arranged along the thickness direction of the dielectric substrate.

Wherein the dielectric substrate 10 includes, but is not limited to, a glass-based.

S12, a connection via 11 penetrating the dielectric substrate 10 along the thickness of the dielectric substrate 10 is formed.

In some examples, the dielectric substrate 1010 may be fabricated using a variety of methods for post via-last/connection via 1111. Such as sand blasting, photosensitive glass, focused discharge, plasma etching, laser ablation, electrochemical, laser induced etching, etc. Different methods have different advantages and disadvantages and application ranges. For example, the sand blasting method has the advantage of simple process, and the connecting via 11 manufactured in the method has larger aperture and is only applicable to manufacturing the connecting via 11 with the aperture larger than 200 μm. The photosensitive glass method has the advantage of simple process and can manufacture the connecting via 11 with high density and high depth-to-width ratio. The focusing discharge method has the advantage of high pore-forming speed. The sidewall roughness of the connection via 11 is small by the plasma etching method. The laser ablation method has the advantages that the connecting via holes 11 with high density and high depth-to-width ratio can be manufactured, and the roughness is large. The electrochemical method has the advantages of low cost, simple equipment, high pore forming rate and larger diameter of the connecting via 11. The laser-induced etching method has the advantages of high pore forming rate, capability of manufacturing the connecting via 11 with high density and high depth-to-width ratio, no damage in the via, and expensive laser equipment. Here, the laser induced etching is taken as an example, and the back through hole is formed on the back surface of the substrate by using a laser induced etching method. The laser is used for carrying out laser-induced modification on the position where the connecting via hole 11 needs to be manufactured, and then a wet etching method is used for manufacturing the via hole. The back through hole can only be manufactured by adopting a single-sided etching method, so that the obtained hole can only be an inverted conical hole, and for the punching method of laser-induced etching, the inverted conical hole with single-sided etching is a typical characteristic of the back through hole connected with the back of the through hole 11.

S13, a connection electrode is formed in the connection via 11, a first conductive structure 21 is formed on the first surface, a second conductive structure 22 is formed on the second surface, and the first conductive structure 21 is electrically connected with the second conductive structure 22 through the connection electrode in the connection via 11 to form a coil structure of the inductor. At least one of the first conductive structure 21 and the second conductive structure 22 is formed with a hollowed pattern.

In some examples, step S13, forming an auxiliary film layer by means including but not limited to magnetron sputtering, then continuously sputtering the first conductive film layer, electroplating the first seed layer by using the first conductive film layer as a seed layer, and removing the redundant electroplated copper on the first surface and the second surface by using a Chemical Mechanical Polishing (CMP) method after the electroplating is completed, thereby forming a connection electrode filling the connection via hole 11. Next, the first conductive structure 21 and the second conductive structure 22 are formed as the first surface through a patterning process. The first conductive structure 21 and the second conductive structure 22 are formed by a patterning process after forming a metal conductive layer by a process including, but not limited to, magnetron sputtering, electroplating, printing, and the like.

The connection electrode is formed by the subtractive method, but may be formed by the additive method.

The auxiliary film layer is used for increasing the adhesive force of the first conductive film layer. The material of the auxiliary film layer includes but is not limited to titanium Ti, and the material of the first conductive film layer includes but is not limited to Cu. The thickness of the auxiliary film layer is about 10nm to 300nm, and the thickness of the first conductive film layer is about 30nm to 100 nm.

In some examples, the method of manufacturing embodiments of the present disclosure may further include forming a first protective layer on a side of the first conductive structure 21 facing away from the dielectric substrate 10 after forming the first conductive structure 21, and forming a second protective layer on a side of the second conductive structure 22 facing away from the dielectric substrate 10 after forming the second conductive structure 22.

Wherein the first protective layer is used for preventing the formation of structures on the first surface of the water oxygen erosion medium substrate 10, and the second protective layer is used for preventing the formation of structures on the second surface of the water oxygen erosion medium substrate 10. The first protective layer material may be an inorganic insulating material. For example, the first protective layer may be an inorganic insulating layer formed of silicon nitride (SiNx), or an inorganic insulating layer formed of silicon oxide (SiO ₂), or several stacked combination film layers of a SiNx inorganic insulating layer and a SiO ₂ inorganic insulating layer. Of course, the material of the first protective layer may also be an organic material, ABF material, or the like. The material of the second protection layer may be the same as that of the first protection layer, so that the description thereof will not be repeated here.

So far, the description of the method for manufacturing the inductor according to the embodiment of the present disclosure has been completed.

In a third aspect, embodiments of the present disclosure provide a filter that may include the above-described inductor. When the filter can also comprise a capacitor and a resistor.

Fig. 10 is a circuit diagram of a filter, which includes two inductors and a capacitor and a resistor, as shown in fig. 10. Wherein, for ease of understanding, the two inductors are referred to as a first inductor L1 and a second inductor L2, respectively. With continued reference to fig. 2, the first lead end of the first inductor L1 is connected to the first end of the resistor R, the second lead end of the first inductor is connected to the second plate of the capacitor C, the first lead end of the second inductor L2 is connected to the first end of the resistor R, and the second lead end of the second inductor L2 is connected to the first plate of the capacitor C.

The resistor R may be implemented by a wire, or may be made of a high-resistance material, such as tin oxide (ITO) or nickel-chromium (NiCr) alloy. In the embodiment of the present disclosure, the formation of the resistor R is not limited, and the capacitance and inductance will be mainly described below.

The first electrode plate of the capacitor in the filter and the first conductive structure 21 of the inductor may be arranged in the same layer, the second electrode plate of the capacitor is arranged on one side of the first electrode plate, which is away from the dielectric substrate 10, and a dielectric layer is arranged between the first electrode plate and the second electrode plate of the capacitor.

The filter comprises the inductor, so that the inductance value is obviously improved, and the performance of the filter is obviously improved. It is to be understood that the above embodiments are merely illustrative of the application of the principles of the present invention, but not in limitation thereof. Various modifications and improvements may be made by those skilled in the art without departing from the spirit and substance of the invention, and are also considered to be within the scope of the invention.

Claims

1. An inductor, comprising:

A dielectric substrate having a connecting via extending through the dielectric substrate in a thickness direction thereof; the dielectric substrate comprising a first surface and a second surface arranged opposite to each other in a thickness direction thereof;

A first conductive structure is disposed on the first surface;

The second conductive structure is disposed on the second surface, and the first conductive structure and the second conductive structure are electrically connected via a connecting electrode located in the connecting via hole to form a coil structure of the inductor; wherein,

At least one of the first conductive structure and the second conductive structure has a hollow pattern;

When the first conductive structure has the hollow pattern, the hollow pattern includes a first opening extending along an extending direction of the first conductive structure;

When the second conductive structure has the hollow pattern, the hollow pattern includes a second opening extending along an extending direction of the second conductive structure.

2. The inductor according to claim 1, wherein when the first conductive structure has the hollow pattern, the first opening has a first side and a second side that are oppositely arranged along the length direction of the first conductive structure; the orthographic projections of the first side and the second side on the plane where the first surface is located respectively fall on the contours of the orthographic projections of the two connecting vias on the plane where the first surface is located;

When the second conductive structure has the hollow pattern, the second opening has a third side and a fourth side that are relatively arranged along the length direction of the second conductive structure; the orthographic projections of the third side and the fourth side on the plane where the first surface is located respectively fall on the contours of the two connecting vias on the plane where the first surface is located.

3. The inductor according to claim 1, wherein when the first conductive structure has the hollow pattern, for one of the first conductive structures and the two connecting vias covering it, the orthographic projection of the first opening of the first conductive structure on the plane where the first surface is located does not overlap with the orthographic projections of the two connecting vias on the plane where the first surface is located;

When the second conductive structure has the hollow pattern, the hollow pattern includes a second opening extending along the extension direction of the second conductive structure; for one second conductive structure and two connecting vias covering it, the orthographic projection of the second opening of the second conductive structure on the plane where the first surface is located has no overlap with the orthographic projection of the two connecting vias on the plane where the first surface is located.

4. The inductor according to claim 1, wherein when the first conductive structure has the hollow pattern, the first opening comprises a fifth side and a sixth side extending along the length direction of the first conductive structure and arranged opposite to each other; the fifth side and the sixth side are straight line segments or broken line segments;

When the second conductive structure has the hollow pattern, the second opening includes a seventh side and an eighth side extending along the length direction of the second conductive structure and arranged opposite to each other; the seventh side and the eighth side are straight line segments or broken line segments.

5. The inductor according to claim 1, wherein when the first conductive structure has the hollow pattern, the center of the orthographic projection of the outer contour of the first conductive structure on the plane where the first surface is located is a first center, the center of the orthographic projection of the first opening on the plane where the first surface is located is a second center, and the first center and the second center coincide with each other;

When the second conductive structure has the hollow pattern, the center of the orthographic projection of the outer contour of the second conductive structure on the plane where the first surface is located is the third center, the center of the orthographic projection of the first opening on the plane where the first surface is located is the fourth center, and the third center coincides with the fourth center.

6. The inductor according to claim 1, wherein when the first conductive structure has the hollow pattern, the hollow pattern includes a plurality of the first openings, and the plurality of the first openings extend along the length direction of the first conductive structure and are arranged side by side in the width direction of the first conductive structure;

When the second conductive structure has the hollow pattern, the hollow pattern includes a plurality of second openings, and the plurality of second openings all extend along the length direction of the second conductive structure and are arranged side by side in the width direction of the second conductive structure.

7 . The inductor according to claim 1 , wherein the thickness of the first conductive structure and the second conductive structure are both greater than 1 μm.

8 . The inductor according to claim 1 , wherein when the first conductive structure has the hollow pattern, the width of the first opening is greater than 10 μm, and when the second conductive structure has the hollow pattern, the width of the second opening is greater than 10 μm.

9. A method for preparing an inductor, comprising:

A dielectric substrate is provided, wherein the dielectric substrate has a connecting via hole penetrating along the thickness direction thereof; the dielectric substrate comprises a first surface and a second surface arranged opposite to each other along the thickness direction thereof;

A connecting electrode is formed in the connecting via hole of the dielectric substrate, a first conductive structure is formed on the first surface, and a second conductive structure is formed on the second surface. The first conductive structure and the second conductive structure are electrically connected through the connecting electrode located in the connecting via hole to form a coil structure of the inductor; wherein,

The first conductive structure formed has a hollow pattern, and/or the second conductive structure formed has a hollow pattern.

10 . The method for preparing an inductor according to claim 9 , further comprising: forming a first protective layer on a side of the first conductive structure away from the first surface; and forming a second protective layer on a side of the second conductive structure away from the second surface.

11. A filter comprising the inductor according to any one of claims 1 to 8.