Multilayer coil structure, inductor and transformer

Abstract

The utility model provides a multi-layer coil structure, an inductor and a transformer. A coil comprises at least two sub-coils which are arranged in a stacked mode. Each sub-coil comprises a bottom coil, an insulating film arranged on the bottom coil and a top coil arranged on the insulating film, a through hole is formed in the insulating film, and a contact is arranged in the through hole, so that the bottom coil and the top coil located on the two sides of the insulating film are in electric contact; insulating layers are arranged on the outer surfaces of the bottom surface coil and the top surface coil; conducting holes are formed in the insulating layers; the conducting holes of the adjacent sub-coils are aligned, and metal contacts are arranged in the conducting holes, so that the adjacent sub-coils are in electric contact; and the through holes and the conducting holes on the same sub-coil are arranged in a staggered manner. Insulation treatment is carried out on the outer surfaces of the sub-coils, the aligned via holes are formed between the adjacent sub-coils, and the conductive materials are filled, so that the insulation problem of a multi-layer multi-coil structure is solved, and the number of coils in a traditional process is broken through under the same height of a product.

Description

Technical Field

[0001] The utility model relates to the field of electronic component manufacturing, and particularly relates to a multi-layer coil structure, an inductor and a transformer. Background Art

[0002] In the semiconductor manufacturing process, coils, as key components, are widely used in various process links such as lithography, etching, ion implantation, etc., and their performance directly affects the process accuracy and yield. The traditional semiconductor processing coil design is mainly limited to double-layer multi-turn or multi-layer single-turn structures. Multi-layer single-turn structure: Such a design is made by etching single-turn double-layer coils on both sides of an insulating film through multi-layer conductive films, and a multi-layer single-turn structure is formed by stacking and welding several single-turn double-layer coils, such as Figure 1 . Double-layer multi-turn structure: Such as Figure 2 , multi-layer thin films are respectively etched into multi-turn coils on both sides of the insulating film. However, due to the aspect ratio problem of etching, the double-layer multi-turn coils cannot be made high enough. Although this design meets the basic process requirements to a certain extent, with the continuous development of semiconductor technology, higher requirements are put forward for the accuracy, stability and reliability of coils.

[0003] If multi-layer multi-turn coils are manufactured, serious challenges will be faced in terms of insulation. Since the number of coil layers increases and the layers need to be closely arranged to achieve efficient electromagnetic conversion, interlayer insulation has become a technical obstacle that is difficult to overcome. The selection of insulating materials, the thickness of the insulating layer, and the optimized design of the interlayer insulation structure are all key factors affecting the coil performance. If the insulation is insufficient, it is easy to cause interlayer short circuits, leading to equipment failures and even safety accidents; if the insulation is too thick, it will affect the electromagnetic performance and heat dissipation efficiency of the coil, reducing the overall process effect.

[0004] Therefore, there is an urgent need for a manufacturing method for a multi-layer multi-turn coil structure that can effectively solve the multi-layer multi-turn insulation problem while ensuring efficient electromagnetic conversion, and improve the accuracy, stability and reliability of the coil to adapt to the rapid development of semiconductor manufacturing technology. Summary of the Utility Model

[0005] In order to solve the above problems, the purpose of the utility model is to provide a multi-layer coil structure, an inductor and a transformer. By insulating the double-sided sub-coils, aligned vias are opened between adjacent sub-coils and filled with conductive materials, so that conduction is achieved between adjacent sub-coils, solving the insulation problem of the multi-layer multi-turn structure. At the same time, under the same height of the product, the number of coil turns breaks through the traditional process.

[0006] The utility model is realized through the following technical solutions:

[0007] A multi-layer coil structure includes:

[0008] At least two stacked sub-coils; each of the sub-coils includes a bottom coil, an insulating film disposed on the bottom coil, and a top coil disposed on the insulating film. A through hole is provided on the insulating film, and the through hole corresponds to the starting end of the top coil and the ending end of the bottom coil respectively. A contact is provided in the through hole to enable electrical contact between the bottom coil and the top coil on both sides of the insulating film; insulating layers are provided on the outer surfaces of the bottom coil and the top coil, and via holes are provided on the insulating layers;

[0009] The via holes of adjacent sub-coils are aligned, and metal contacts are provided in the via holes to enable electrical contact between adjacent sub-coils;

[0010] The through hole and the via hole on the same sub-coil are arranged in a staggered manner.

[0011] Furthermore, the total wire width of each sub-coil is the same.

[0012] Furthermore, the via hole of the sub-coil at the bottom layer corresponds to the ending end of its top coil, and the via hole of the sub-coil at the top layer corresponds to the starting end of its bottom coil; the via holes of the sub-coils in the middle correspond to the starting end of the bottom coil and the ending end of the top coil respectively.

[0013] An inductor includes the above multi-layer coil structure and further includes a magnet covering the multi-layer coil structure.

[0014] A transformer includes the above multi-layer coil structure.

[0015] Compared with the prior art, the technical solution and its beneficial effects of the present utility model are as follows:

[0016] (1) In the multi-layer coil structure of the present utility model, insulation treatment is performed on the outer surface of the sub-coil, and aligned via holes are opened between adjacent sub-coils and filled with conductive materials, so that electrical conduction is achieved between adjacent sub-coils. The insulation problem of the multi-layer and multi-turn structure is solved. At the same time, within the same size as the traditional coil, the total number of turns of the multi-layer single-turn structure is exceeded, thereby enabling the manufacture of products with a larger performance range.

[0017] (2) In the multi-layer coil structure of the present utility model, the number of turns of the bottom coil and the top coil of each sub-coil can be freely designed, so as to form products with different inductance values, which are flexible and have a wide application range. Description of the Drawings

[0018] Figure 1 is a cross-sectional view of the multi-layer single-turn coil structure of the prior art provided by the present utility model;

[0019] Figure 2It is a cross-sectional view of the prior art double-layer multi-turn coil structure provided by the present utility model;

[0020] Figure 3 It is a cross-sectional view of a multi-layer multi-turn coil structure provided by an embodiment of the present utility model;

[0021] Figures 4 - 8 It is a schematic diagram of the manufacturing steps of the multi-layer multi-turn coil structure provided by an embodiment of the present utility model;

[0022] Figures 9 - 11 It is a schematic diagram of a multi-layer single-turn coil structure provided by an embodiment of the present utility model;

[0023] Figures 12 - 14 It is a schematic diagram of a multi-layer multi-turn coil structure provided by an embodiment of the present utility model;

[0024] Figure 15 It is a schematic diagram of a certain double-layer multi-turn coil structure provided by an embodiment of the present utility model.

[0025] Illustration:

[0026] Sub-coil - 10; bottom coil - 11; top coil; insulating film - 13; contact - 14; insulating layer - 20; via hole - 21; metal contact - 22;

[0027] First sub-coil - 100, 400, first contact - 101, 401; first via hole - 102, 402; first electrode end - 130, 430;

[0028] Second sub-coil - 200, 500, second contact - 201, 501; second via hole - 202, 502; third via hole - 203, 503;

[0029] Third sub-coil - 300, 600; third contact - 301, 601; fourth via hole - 302, 602; second electrode end - 330, 630. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0031] Refer to Figure 3, A multi-layer coil structure includes at least two sub-coils 10 stacked on top of each other. Each sub-coil 10 includes a bottom coil 11, an insulating film 13 disposed on the bottom coil 11, and a top coil 12 disposed on the insulating film 13. Here, the bottom coil 11 and the top coil 12 are formed by etching a conductive metal or multiple stacked conductive metals to obtain the required pattern. A through hole (not shown) is provided on the insulating film, and the through hole corresponds to the starting end of the top coil and the ending end of the bottom coil respectively. A contact 14 is provided in the through hole, and through the contact 14, electrical contact is made between the bottom coil 11 and the top coil 12 located on both sides of the insulating film 13.

[0032] Insulating layers are provided on the outer surfaces of both the bottom coil and the top coil. Through holes are provided on the insulating layers. The through holes of adjacent sub-coils are aligned with each other, and metal contacts are provided in the through holes to enable electrical contact between adjacent sub-coils. It can be understood that the through holes and the through holes on the same sub-coil are arranged in a staggered manner to avoid short-circuiting of the conductive coils.

[0033] In this embodiment, the total line width of each sub-coil is the same, so that the stability of the multi-layer coil structure is better. The total line width refers to the width from the inner side to the outer side of a single-sided coil. The through holes correspond to the starting end of the bottom coil and the ending end of the top coil respectively, so that the current flowing path is longer.

[0034] During operation: The current flowing into the starting end (electrode end) of the bottom coil of the bottom-layer sub-coil can flow from the ending end of the bottom coil through the contact into the starting end of the top coil, and finally flow out from the ending end of the top coil, and then flow into the starting end of the bottom coil of the next sub-coil through the metal contact. In this way, it continues until it flows out from the ending end (electrode end) of the top coil of the top-layer sub-coil.

[0035] This embodiment also provides a manufacturing method for a multi-layer multi-turn coil structure, and the steps are as follows:

[0036] S1. Prepare at least two full-panel double-sided coils. Each full-panel double-sided coil includes a number of sub-coils arranged in an array. Each sub-coil is a double-sided coil. In this embodiment, the number of turns of each side coil of each sub-coil ≥ 1. For the convenience of clear identification, Figure 4 and the subsequent drawings only show the structure of the sub-coil or the single coil. As Figure 4 , the current flows into from the starting end of the bottom coil, flows through the pattern of the bottom coil, flows from the ending end of the bottom coil through the contact to the starting end of the top coil, and finally flows out from the ending end of the top coil, as shown by the arrow.

[0037] The production method of the double-sided coil includes:

[0038] S11. Lay the first conductive metal;

[0039] S12. Etch a number of bottom coil patterns on the first conductive metal. In this embodiment, the number of coil turns ≥ 1. It should be noted that the number of coil turns is not limited to full turns (integer turns), and can be four-fifths of a turn, five-sixths of a turn, etc., so as to refine the accuracy of the number of coil turns, better match the required designed inductance value, cover all product inductance values on the market, and have a wide range of applications.

[0040] S13. Lay an insulating film above the first conductive metal. Through holes are provided on the insulating film, and the through holes correspond to the ends of the bottom coils one by one.

[0041] S14. Set contacts in the through holes, and the upper end surfaces of the contacts protrude above the upper surface of the insulating film.

[0042] S15. Lay a second conductive metal above the insulating film.

[0043] S16. Etch a number of top coil patterns on the second conductive metal. The starting ends of the top coils correspond to the through holes one by one. Similarly, the number of turns of the top coils can also be non-integer turns. The top coils are in contact with the contacts, so as to obtain a whole plate of incoming materials containing a number of double-sided coils. The pattern of each bottom coil in the same whole plate is the same, and the pattern of each top coil is the same.

[0044] S2. Insulate each whole plate of double-sided coils so that an insulating layer is coated on the outer surface of each whole plate of double-sided coils. For example Figure 5 , the outer surface of the double-sided coils includes the top surface and side surfaces of the bottom coils and top coils, so as to achieve insulation between multiple turns of coils.

[0045] The methods for coating the insulating layer on the double-sided coils include: vacuum coating the double-sided coils so that an insulating layer is coated on the outer surface of the double-sided coils. The materials for forming the insulating layer include parylene or silicon dioxide. It can also be that a printing process is used so that an insulating layer is coated on the outer surface of the double-sided coils. The materials for forming the insulating layer include epoxy resin or UV immobilizing glue. It can also be that a dispensing process is used so that an insulating layer is coated on the outer surface of the double-sided coils. The materials for forming the insulating layer include epoxy resin or UV immobilizing glue.

[0046] S21. Identify the whole plate of double-sided coils after insulation treatment to detect whether the outer surface of the coils is completely covered with an insulating layer.

[0047] S3. Open vias, such as Figure 6 . Specifically, remove the insulating layer corresponding to the starting end of each bottom coil of the whole plate of double-sided coils located at the top layer, remove the insulating layer corresponding to the end of each top coil of the whole plate of double-sided coils located at the bottom layer, remove the insulating layer corresponding to the starting end of the bottom coil and the end of the top coil of the whole plate of double-sided coils located in the middle, and form vias for the coils to conduct with the outside.

[0048] S4. Fill the via holes of the top surface coil with a conductive material, such as metal contact 22, such as Figure 7 . The height of the conductive material is greater than twice the height of the surrounding insulating layer, so that the conductive material can pass through the two aligned via holes.

[0049] S5. Stack and bond several double-sided coils processed through S2, S3, and S4, and the via holes of adjacent double-sided coils are aligned, such as Figure 8 . The adjacent double-sided coils are electrically connected through the metal contact 22 disposed in the via hole 21.

[0050] S6. Heat to make the insulating layers of adjacent double-sided coils adhere and fix, thereby forming a multi-layer and multi-turn coil structure, such as Figure 3 .

[0051] S7. Cut to obtain a single coil formed by stacking several sub-coils. The end of the top surface coil of the top-layer sub-coil and the start end of the bottom surface coil of the bottom-layer sub-coil are respectively the two electrode ends of the single coil.

[0052] Refer to Figures 9 to 11 . Taking each sub-coil as a double-layer single-turn coil as an example, the multi-layer coil structure of the present application will be described below.

[0053] Figure 9 shows the structure of the first sub-coil 100. The a-plane is a top view from the direction of the bottom surface coil, and the b-plane is a top view from the direction of the top surface coil. The start end of the bottom surface coil 110 of the first sub-coil 100 is the first electrode end 130. A via hole is formed in the insulating film corresponding to the end of the bottom surface coil 110 and a first contact 101 is provided. The current flows in from the first electrode 130, reaches the end of the bottom surface coil 110 of the first sub-coil 100, then flows through the first contact 101 to the start end of the top surface coil 120 of the first sub-coil 100, and finally is led out from the conductive material in the first via hole 102 provided at the end of the top surface coil 120.

[0054] Figure 10 shows the structure of the second sub-coil 200. The a-plane is a top view from the direction of the bottom surface coil, and the b-plane is a top view from the direction of the top surface coil. A second via hole 202 is formed in the insulating layer corresponding to the start end of the bottom surface coil 210 of the second sub-coil 200, and the opening position of the second via hole 202 is aligned with the first via hole 102.

[0055] The starting end of the bottom coil 210 is electrically connected to the ending end of the top coil 120 through the conductive material disposed in the first via 102. The current flows from the conductive material in the first via 102 to the starting end of the bottom coil 210, then to the ending end of the bottom coil 210, and is conducted to the starting end of the top coil 220 of the second sub-coil 200 through the second contact 201 disposed at the ending end of the bottom coil 210, and finally led out through the conductive material in the third via 203 disposed at the ending end of the top coil 220.

[0056] Figure 11 In [figures], the structure of the third sub-coil 300 is shown. The a side is a top view from the direction of the bottom coil, and the b side is a top view from the direction of the top coil. An insulating layer corresponding to the starting end of the bottom coil 310 of the third sub-coil 300 is provided with a fourth via 302, and the opening position of the fourth via 302 is aligned with the third via 203.

[0057] The starting end of the bottom coil 310 of the third sub-coil 300 is electrically connected to the ending end of the top coil 220 of the second sub-coil 200 through the conductive material disposed in the third via 303. The current flows from the conductive material in the third via 203 to the starting end of the bottom coil 310, then to the ending end of the bottom coil 310, and is conducted to the starting end of the top coil 320 of the third sub-coil 300 through the third contact 301 disposed at the ending end of the bottom coil 310, and finally flows out from the ending end of the top coil 320, i.e., the second electrode terminal 330.

[0058] It can be understood that there can be several second sub-coils rather than being limited to one as shown in the example, and the design can be adjusted according to needs. In the traditional manufacturing method of single-turn multi-layer coils, three double-layer single-turn sub-coils can form a four-layer single-turn coil structure (the top coil of the first sub-coil and the bottom coil of the second sub-coil are soldered to form one layer, and the top coil of the second sub-coil and the top coil of the third sub-coil are soldered to form one layer), that is, four coils. By using the multi-layer coil manufacturing method of the present invention, three double-layer single-turn sub-coils can form a six-layer single-turn coil structure, that is, six coils. It can be seen that with the same number of consumed sub-coils, the formed multi-layer coil structure contains more coils. Under the same size as the traditional coil, the total number of turns of the multi-layer single-turn structure is exceeded, thereby realizing the manufacture of products with a larger performance range.

[0059] Refer to Figures 12 to 14 , and hereinafter, taking each sub-coil as a double-layer multi-turn coil as an example, the multi-layer coil structure of the present invention will be described.

[0060] Figure 12In it, the structure of the first sub-coil 400 is shown. The a side is a top view from the bottom coil direction, and the b side is a top view from the top coil direction. The starting end of the bottom coil 410 of the first sub-coil 400 is the first electrode end 430. A through hole is provided in the insulating film corresponding to the end of the bottom coil 410 and a first contact 401 is provided. Current flows in from the first electrode 430, reaches the end of the bottom coil 410 of the first sub-coil 400, and then flows through the first contact 401 to the starting end of the top coil 420 of the first sub-coil 400, and finally is led out from the conductive material in the first via hole 402 provided at the end of the top coil 420.

[0061] Figure 13 In it, the structure of the second sub-coil 500 is shown. The a side is a top view from the bottom coil direction, and the b side is a top view from the top coil direction. A second via hole 502 is provided in the insulating layer corresponding to the starting end of the bottom coil 510 of the second sub-coil 500, and the opening position of the second via hole 502 is aligned with the first via hole 402.

[0062] The starting end of the bottom coil 510 is conducted to the end of the top coil 420 through the conductive material in the first via hole 402. Current flows from the conductive material in the first via hole 402 to the starting end of the bottom coil 510, then to the end of the bottom coil 510, and is conducted to the starting end of the top coil 520 of the second sub-coil 500 through the second contact 501 provided at the end of the bottom coil 510, and finally is led out from the conductive material in the third via hole 503 provided at the end of the top coil 520.

[0063] Figure 14 In it, the structure of the third sub-coil 600 is shown. The a side is a top view from the bottom coil direction, and the b side is a top view from the top coil direction. A fourth via hole 602 is provided in the insulating layer corresponding to the starting end of the bottom coil 610 of the third sub-coil 600, and the opening position of the fourth via hole 602 is aligned with the third via hole 503.

[0064] The starting end of the bottom coil 610 of the third sub-coil 600 is conducted to the end of the top coil 520 of the second sub-coil 500 through the conductive material in the third via hole 503. Current flows from the conductive material in the third via hole 503 to the starting end of the bottom coil 610, then to the end of the bottom coil 610, and is conducted to the starting end of the top coil 620 of the third sub-coil 600 through the third contact 601 provided at the end of the bottom coil 610, and finally flows out from the end of the top coil 620, that is, the second electrode end 630.

[0065] It can be understood that there can be several second sub-coils instead of being limited to one in the example, and the design can be adjusted according to needs. By insulating each double-sided sub-coil, the multi-layer and multi-turn coil structure of the present utility model not only solves the insulation problem between coil gaps, but also enables more layers to be formed in the same volume of the product, that is, more turns are obtained.

[0066] In the example of the multi-layer and multi-turn coil structure formed by each of the foregoing sub-coils being a double-layer and multi-turn structure, the number of turns of each illustrated sub-coil is the same (three turns). In actual use, the number of turns of the bottom coil and the top coil of each sub-coil can be designed according to requirements. For example, the second sub-coil 500 with three turns for both the top coil and the bottom coil can be designed to have a structure with two turns for both the top coil and the bottom coil, such as Figure 15 , and it only needs to satisfy that the adjacent vias are aligned after the sub-coils are stacked. Thus, the multi-layer coil structure produced by the present utility model can be self-combined to generate several structures with different inductance values, and has a wide range of applications; it makes up for the disadvantages of insufficient saturation and excessive DCR in the design of products with specific inductance values by traditional multi-layer single-turn and double-layer multi-turn.

[0067] The above description shows and describes the preferred embodiments of the present utility model. It should be understood that the present utility model is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept of the present utility model herein through the above teachings or the technology or knowledge in related fields. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present utility model should fall within the protection scope of the appended claims of the present utility model.

Claims

1. A multi-layer coil structure, characterized in that, Comprising: At least two sub-coils arranged in a stacked manner; each of the sub-coils includes a bottom coil, an insulating film disposed on the bottom coil, and a top coil disposed on the insulating film. A through hole is provided on the insulating film, and the through hole corresponds to the starting end of the top coil and the ending end of the bottom coil respectively. A contact is provided in the through hole to enable electrical contact between the bottom coil and the top coil on both sides of the insulating film; insulating layers are provided on the outer surfaces of the bottom coil and the top coil, and via holes are provided on the insulating layers; The via holes of adjacent sub-coils are aligned, and metal contacts are provided in the via holes to enable electrical contact between adjacent sub-coils; The through hole and the via hole on the same sub-coil are arranged in a misaligned manner.

2. The multi-layer coil structure according to claim 1, wherein The total line width of each sub-coil is the same.

3. A multi-layer coil structure according to claim 1, characterized in that, The via hole of the sub-coil located at the bottom layer corresponds to the ending end of its top coil, and the via hole of the sub-coil located at the top layer corresponds to the starting end of its bottom coil; the via holes of the sub-coils located in the middle correspond to the starting end of the bottom coil and the ending end of the top coil respectively.

4. An inductor, characterized in that, Comprising the multi-layer coil structure according to any one of claims 1 to 3, further comprising a magnet covering the multi-layer coil structure.

5. A transformer, characterized in that, Comprising the multi-layer coil structure according to any one of claims 1 to 3.

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