Ferroalloy coatings for wireless recharging devices and related methods

Abstract

Coatings for wireless recharging devices are generally described that include an iron alloy that includes iron and at least one additional metal (e.g., cobalt and / or nickel). The coating may be applied directly to a substrate, such as a printed circuit board.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit under 35 USC § 119(e) of U.S. Non-Provisional Application No. 18 / 169,815, filed on February 15, 2023, and entitled “IRONALLOY COATINGS FOR WIRELESS RECHARGING DEVICES AND RELATED METHODS,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] Iron alloys containing iron and additional metals (eg, cobalt and / or nickel) for use in wireless recharging devices are generally described. Background Art

[0004] Wireless charging coils, such as those found on mobile phones, can provide quick and easy charging. However, these charging systems can be inefficient and slow to charge. The inductive coupling between the transmitting and receiving coils can be improved by changing the conductors used to make these coils. Summary of the Invention

[0005] Iron alloys containing iron and additional metals (eg, cobalt and / or nickel) for use in wireless recharging devices are generally described.

[0006] In one aspect, an article is described that includes a coil and a metal coating comprising an iron alloy deposited on the coil, wherein at least a portion of a surface of the coil is free of the metal coating.

[0007] In another aspect, a circuit board is described that includes a plurality of traces on the circuit board, and a metal coating comprising an iron alloy deposited on a first trace of the plurality of traces; wherein a portion of the first trace is free of the metal coating.

[0008] In another aspect, a method of manufacturing a coil on a circuit board includes forming a first trace on the circuit board and coating the first trace with a metal coating comprising an iron alloy, wherein at least a portion of the first trace is free of the metal coating.

[0009] Other advantages and novel features of the present disclosure will become apparent from the following detailed description of a number of non-limiting embodiments of the present invention when considered in conjunction with the accompanying drawings. In the event that this specification and the documents incorporated by reference contain conflicting and / or inconsistent disclosures, this specification shall prevail. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown is generally represented by a single reference numeral. For clarity, not every component is labeled in every figure, nor is every component of every embodiment of the invention shown, where illustration is not required for one of ordinary skill in the art to understand the invention. In the drawings:

[0011] Figure 1A schematically depicts an apparatus including a circuit board including a plurality of traces formed on the circuit board, wherein the plurality of traces includes a first trace, according to some embodiments;

[0012] Figure 1B is a schematic diagram illustrating that a first trace among a plurality of traces on a circuit board is at least partially coated according to some embodiments;

[0013] Figure 1C is a side perspective view of a circuit board schematically illustrating traces partially coated with a coating according to some embodiments;

[0014] Figure 1D is a side perspective view of a circuit board in which a coating extends from a first trace to a second trace to contact underlying material according to some embodiments;

[0015] Figure 1E shows a schematic side perspective view of a circuit board with a plurality of traces applied to the top of the circuit board and a coating applied to at least one of the traces according to some embodiments; and

[0016] Figure 1F A device comprising a circuit board with further components is schematically depicted, wherein the circuit board comprises a trace in a coil shape, and wherein at least a portion of the coil-shaped trace may be partially coated with an iron alloy, according to some embodiments. DETAILED DESCRIPTION

[0017] The following generally describes articles and systems (e.g., devices) including iron alloy coatings and related methods. The iron alloy can be deposited as a coating onto a metal or surface (e.g., a surface adjacent to a metal) and can contain other metals within the iron alloy, such as cobalt and / or nickel. In some cases, the coating can be applied to a circuit board (e.g., a printed circuit board, PCB) as part of a wireless recharging device. Advantageously, the coating can be applied directly to the circuit board. For cases where the coating has a specific shape (e.g., a coil), this can eliminate the need to separately manufacture the specific shape and then subsequently apply the manufactured shape to the circuit board. By using the articles, systems, and methods described herein, the shape can be applied directly to the circuit board (e.g., to one or more traces of the circuit board), thereby reducing manufacturing time and / or costs (e.g., by forming the shape directly on the circuit board, less material is required). Other applications of iron alloys are described in more detail below.

[0018] Turning to the drawings, specific non-limiting embodiments are described in further detail. It should be understood that the various systems, components, features, and methods described with respect to these embodiments may be used alone and / or in any desired combination, as the present disclosure is not limited to the specific embodiments described herein.

[0019] As an example, Figure 1A The apparatus 100 is schematically depicted as including a circuit board 110. A plurality of traces 120 may be formed on or in the circuit board 110, for example, by printing, etching, or other techniques. Details regarding techniques for forming traces in the circuit board are described elsewhere herein. In some embodiments, the circuit comprises metal (e.g., copper) or other types of conductive materials, and forming the first trace exposes the metal or conductive material of the circuit board (e.g., etching a layer of the circuit board to expose the copper or some other underlying material). By way of illustration and not limitation, Figure 1A The underlying material 124 is shown exposed by the formation of trace 120A.

[0020] In some embodiments, the coating is applied to or adjacent to one or more traces. Figure 1B , first trace 120A is partially coated with partial coating 125. The coating need not be applied to the entire trace, and in some embodiments, the coating is applied to only a portion of the trace (e.g., one surface of the trace, both surfaces of the trace). By way of example (and not limitation), Figure 1C Shows about Figure 1A and Figure 1B Another perspective view of the circuit board 110. Figure 1C, the side perspective view depicts a plurality of traces 120 etched into the circuit board 110. As shown in the figure, Figure 1A For example, for the first trace shown as 122A in FIG, the coating of first trace 122B is applied to only a portion of the trace, leaving at least a portion of first trace 122A uncoated. Advantageously, by coating only a portion of one or more traces, the amount of material required to coat the traces is reduced, for example, compared to coating an entire wire and placing it on a circuit board. That is, one advantage of forming a coating directly on a circuit board is that it reduces the amount of material required to form the coating and / or coat an object (e.g., a coil). However, in other embodiments, the entire trace (and / or each of a plurality of traces) is coated.

[0021] In some embodiments, at least a portion of a trace (e.g., a first trace) on a circuit board is coated such that the thickness of the coating extends beyond the surface of the circuit board. Figure 1D In FIG. 1 , the coating 125 applied to the first trace 122C extends beyond the top surface of the circuit board 110. In this manner, objects that are not flush with the circuit board can be formed in and / or on the circuit board. In some embodiments, the coating can join or connect the two traces (e.g., approaching the underlying material of the first and second traces). For example, in FIG. Figure 1D In the embodiment, coating 125 is applied to first trace 122 and second trace 123 such that underlying material 125 contacts the coating on one side of first trace 122 and second trace 123 .

[0022] In some embodiments, a trace or a plurality of traces are applied to a substrate (e.g., a flexible substrate). In some such embodiments, the coating can be applied (directly) to the trace (e.g., the first trace of the plurality of traces). By way of example (and not limitation), Figure 1E One embodiment is schematically depicted where a plurality of traces 120 are on top of a circuit board 110. As shown in the figure, a coating 125 can be deposited directly on one of the plurality of traces 120.

[0023] The first trace (and / or the coating formed on or near the first trace) can have any desired shape. For example, in some embodiments, the first trace (and / or the object formed on or in the first trace) is in the shape of a coil. Figure 1FAs can be seen in the figure, the first trace 122D is in the form of a coil. As shown in the figure, the trace can be (at least partially) coated to form a coating in the shape of a coil (e.g., a coiled wire including a coating). In comparison, if the wire is first coated, coiled, and then placed on a circuit board, at least a portion of the coating will be covered when the wire is applied to the circuit board. By using the articles and methods described herein, at least a portion of the trace can have a surface that is not coated with the coating, thereby improving the ease of manufacturing the coil (or some other shape deposited on the trace). In some embodiments, the uncoated surface of the trace is an unexposed portion of the trace (e.g., not directly on the surface of the substrate or circuit board, but a layer adjacent to the surface of the substrate).

[0024] It should be understood that when a part (e.g., a layer, structure, coating) is “on,” “adjacent to,” “proximate to,” “above,” “over,” “covering,” or “supported by” another part, it can be directly on that part, or there can be an intervening part (e.g., layer, structure, region, coating). Similarly, when a part is “below” or “beneath” another part, it can be directly below that part, or there can be an intervening part (e.g., layer, structure, region). A part that is “directly adjacent to,” “directly on,” “immediately adjacent to,” “in contact with,” or “directly supported by” another part means that there are no intervening parts. It should also be understood that when a part is referred to as being “on,” “above,” “adjacent to,” “over,” “covering,” “in contact with,” “below,” or “supported by” another part, it can cover the entire part or a portion of that part.

[0025] In some embodiments, the device includes additional components (e.g., a power supply, one or more transistors, circuitry). Figure 1F As shown in , the apparatus 100 further includes an additional component 130 .

[0026] While the figures refer to the first trace, it should be understood that the features of the first trace can be applied to any of the plurality of traces (e.g., the second, third, fourth, and fifth traces). That is, any of the plurality of traces can be coated and / or partially coated, depending on the needs of a particular application. Furthermore, like the first trace, at least some of the other traces in the plurality of traces can be partially or fully coated.

[0027] As described above, a coating (e.g., a metallic coating) can be applied to a circuit board (e.g., a printed circuit board). However, it should be understood that the coating can be applied to a variety of articles, such as wires, substrates (e.g., silicon substrates, copper substrates), etc. In many embodiments, the coating comprises an iron alloy. The iron alloy comprises at least 30% by weight iron (Fe) relative to the other metals of the alloy (e.g., nickel, cobalt, another metal). Details regarding the iron alloy are described below and elsewhere herein.

[0028] In some embodiments, the coating is adjacent to the trace (or adjacent to the copper layer below the trace). In some embodiments, the first layer is deposited on the first trace. In some embodiments, the coating includes multiple layers (e.g., a first layer, a second layer, a third layer) deposited onto the trace (or onto the copper layer below the trace).

[0029] The thickness of a coating (e.g., a coating comprising an iron alloy) can be measured in microns (μm) using x-ray fluorescence (XRF). In some embodiments, the coating has a thickness greater than or equal to 0.1 μm, greater than or equal to 1 μm, greater than or equal to 2 μm, greater than or equal to 5 μm, greater than or equal to 10 μm, greater than or equal to 20 μm, greater than or equal to 30 μm, or greater than or equal to 50 μm. In some embodiments, the coating has a thickness less than or equal to 50 μm, less than or equal to 30 μm, less than or equal to 20 μm, less than or equal to 10 μm, less than or equal to 2 μm, less than or equal to 1 μm, or less than or equal to 0.1 μm. Combinations of the above ranges are also possible (e.g., less than or equal to 50 μm and greater than or equal to 0.1 μm). Other ranges are possible. It will be appreciated and understood from this disclosure that the coating can advantageously have a relatively small thickness (e.g., relative to a circuit board) compared to certain existing coatings (e.g., coated wire, existing coils) and systems.

[0030] In some embodiments, the coating comprises an iron alloy. For example, in some embodiments, the amount of the iron alloy is greater than or equal to 15 weight percent, greater than or equal to 20 weight percent, greater than or equal to 25 weight percent, greater than or equal to 30 weight percent, greater than or equal to 35 weight percent, greater than or equal to 40 weight percent, or greater than or equal to 50 weight percent. In some embodiments, the amount of iron in the iron alloy is less than or equal to 50 weight percent, less than or equal to 40 weight percent, less than or equal to 35 weight percent, less than or equal to 30 weight percent, less than or equal to 25 weight percent, less than or equal to 20 weight percent, or less than or equal to 15 weight percent. Combinations of the above ranges are also possible (e.g., greater than or equal to 20 weight percent and less than or equal to 30 weight percent). Other ranges are possible. In the case where the entire alloy is not iron, the alloy contains other metals, such as nickel and / or cobalt as non-limiting examples of other metals. For example, the iron alloy coating can be an alloy of only iron and nickel, wherein the nickel content is 35 weight percent to 45 weight percent, and therefore the remaining weight percent will be 65 weight percent to 55 weight percent iron, respectively. As another example, in some embodiments, the iron alloy is a ternary alloy with concentrations of 15 to 25 wt % Ni, 35 to 55 wt % Co, and the balance Fe (ie, 20 to 50 wt % iron).

[0031] In some embodiments, the iron alloy includes metals other than iron. For example, in some embodiments, the metallic iron alloy further includes nickel (Ni), cobalt (Co), copper (Cu), magnesium (Mg), manganese (Mn), and / or zinc (Zn). Advantageously, the inclusion of nickel in the alloy can increase the inductance of the coating (or an object formed from the coating, such as a coil) without significantly increasing the electrical resistance of the coating. Other advantages of other metals are contemplated.

[0032] For some embodiments, the ferroalloy comprises one or more other metals, such as cobalt and / or nickel. In some embodiments, the amount of one or more other metals is independently greater than or equal to 20 weight %, greater than or equal to 25 weight %, greater than or equal to 30 weight %, greater than or equal to 35 weight %, greater than or equal to 40 weight %, greater than or equal to 45 weight %, or greater than or equal to 50 weight %. In some embodiments, the amount of one or more other metals is independently less than or equal to 50 weight %, less than or equal to 45 weight %, less than or equal to 40 weight %, less than or equal to 35 weight %, less than or equal to 30 weight %, or less than or equal to 20 weight %. Combinations of the above ranges are also possible (e.g., greater than or equal to 30 weight % and less than or equal to 50 weight %). Other ranges are possible. For a total of 100 weight % comprising nickel, iron, and any other metal present, the weight % of the remainder of the metal in the alloy can be a mixture of iron or iron and other metals. For example, in some embodiments, the ferroalloy is 60 weight % iron, 20 weight % nickel, and 20 weight % cobalt. Of course, other combinations of amounts of metals are possible, as the present disclosure is not limited thereto.

[0033] In some embodiments, the iron alloy is a binary alloy having two metals. For example, in some embodiments, the iron alloy is an iron-nickel alloy comprising iron and nickel. In some embodiments, the iron alloy is an iron-cobalt alloy comprising iron and cobalt. In some embodiments, the iron alloy is a ternary alloy. For example, in some embodiments, the iron alloy is an iron-nickel-cobalt alloy comprising iron, nickel, and cobalt. In some such embodiments, nickel and cobalt are present in a 1:1 ratio (by weight). In some embodiments, the iron alloy is a quaternary alloy comprising iron and at least three other metals (e.g., nickel, cobalt, and another metal, such as zinc). For the iron alloy, other combinations of metals and iron are contemplated, as the present disclosure is not limited thereto.

[0034] In some embodiments, the ternary iron alloy includes nickel and cobalt. In some such embodiments, the ratio of nickel to cobalt can have a specific ratio (e.g., a ratio of nickel to cobalt by weight). In some embodiments, the ratio of nickel to cobalt is greater than or equal to 0.5, greater than or equal to 0.7, greater than or equal to 1, greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.3, greater than or equal to 1.5, greater than or equal to 1.7, or greater than or equal to 2. In some embodiments, the ratio of nickel to cobalt is less than or equal to 2, less than or equal to 1.7, less than or equal to 1.5, less than or equal to 1.3, less than or equal to 1.2, less than or equal to 1.1, less than or equal to 1, less than or equal to 0.7, or less than or equal to 0.5. Combinations of the above ranges are also possible (e.g., greater than or equal to 0.8 and less than or equal to 1.2). Other ranges are possible, as the present disclosure is not limited thereto.

[0035] In some embodiments, the iron alloy comprises a specific crystal structure. For example, in some embodiments, the iron alloy comprises a body-centered cubic (bcc) or face-centered cubic (fcc) crystal structure. In some embodiments, the crystal structure of the iron alloy is a hexagonal close packed (hcp) crystal structure. Other crystal structures are possible. In some embodiments, the iron alloy comprises a mixture of two or more crystalline phases. For example, in some embodiments, the iron alloy comprises a mixture of a face-centered cubic crystal structure and a body-centered cubic crystal structure (i.e., the grains comprise a mixture of face-centered cubic unit cells and body-centered cubic unit cells). In some embodiments, the iron alloy comprises a mixture of a face-centered cubic crystal structure, a body-centered cubic crystal structure, and / or a hexagonal close packed crystal structure.

[0036] For some embodiments, the ferroalloy may have a nanocrystalline microstructure. As used herein, a "nanocrystalline" structure refers to a structure in which the number average size of the grains of the alloy is less than one micron. The number average size of the grains provides the same statistical weight to each grain and is calculated as the sum of all spherical equivalent grain diameters in a representative volume of the body divided by the total number of grains. Without wishing to be bound by any particular theory, alloys or layers of alloys having a nanocrystalline microstructure include nanoscale grains that provide improved magnetic properties and / or improved wireless charging. However, some embodiments may have layers having an amorphous structure or a partially amorphous structure. As understood by those skilled in the art, an amorphous structure is a non-crystalline structure characterized by the absence of long-range symmetry in the positions of the atoms. Examples of amorphous structures include glass or glassy structures.

[0037] In some embodiments, the iron alloy further comprises a dopant. In some such embodiments, the dopant comprises a rare earth metal. Examples of rare earth metals include cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr), promethium (Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium (Tm), ytterbium (Yb), and yttrium (Y). One advantage of including a rare earth metal in the iron alloy is that it improves the magnetic properties of the iron alloy (e.g., the magnetic properties of metal coated with the iron alloy containing the dopant). The dopant can be present in any suitable amount. For example, the dopant may be present in the alloy in an amount of less than or equal to 5 wt %, less than or equal to 3 wt %, less than or equal to 1 wt %, less than or equal to 0.1 wt %, or less than or equal to 0.01 wt %, or less (e.g., less than 1 ppm, less than 1 ppb). In some embodiments, the amount of dopant is greater than or equal to 0.01 wt %, greater than or equal to 0.1 wt %, greater than or equal to 1 wt %, or greater than or equal to 3 wt %. Combinations of the foregoing ranges are also contemplated (e.g., greater than or equal to 0.01 wt % and less than or equal to 5 wt %). Of course, other ranges are possible, as the present disclosure is not limited in this regard.

[0038] In some embodiments, the coating is annealed. For example, in some embodiments, an iron alloy coating is applied (e.g., to the first trace) and the coating is further annealed. Annealing (e.g., an annealing process) can be accomplished by heating the coating and allowing the coating to slowly cool. However, other annealing methods are also possible, such as chemical annealing or plasma annealing, as non-limiting examples. Advantageously, annealing the coating can improve the ductility of the object to which the coating is applied.

[0039] In some embodiments, an iron alloy is applied as a coating to an object. As mentioned above, in some embodiments, the coating has the shape of a wire or coil (e.g., a coiled wire). Advantageously, the coil (including the iron alloy coating described herein) can be used for wireless charging and / or inductive charging. In some such embodiments, the coating is deposited on a circuit board (e.g., a printed circuit board, PCB). Of course, other shapes (e.g., circular, square, rectangular, etc.) are possible, as the present disclosure is not limited thereto.

[0040] The iron alloy coating can be applied via electrodeposition or electroplating, as described in more detail below. However, other methods that do not require electroplating can be used to produce these alloys. In some embodiments, physical vapor deposition (PVD) can be used to produce the coating (e.g., on PCB traces). Electroless plating can also be used to produce these alloys. Other methods are possible, as the present disclosure is not limited thereto.

[0041] In some embodiments, only a portion (e.g., only three surfaces, only two surfaces, only one surface) of the coil (or some other coated article) is coated with a coating (e.g., a metal coating, an iron alloy coating). In some embodiments, greater than or equal to 25%, greater than or equal to 50%, or greater than or equal to 75% of the coil is coated. In some embodiments, less than or equal to 75%, less than or equal to 50%, or less than or equal to 25%. Combinations of the above ranges are also possible (e.g., greater than or equal to 25% and less than or equal to 75%). Other ranges are also possible.

[0042] In some embodiments, at least a portion of the coil (or some other coated article) is free of a coating (e.g., a metallic coating). In some embodiments, greater than or equal to 0.1%, greater than or equal to 1%, greater than or equal to 10%, greater than or equal to 25%, greater than or equal to 50%, or greater than or equal to 75% of the coil is free of a coating. In some embodiments, less than or equal to 75%, less than or equal to 50%, or less than or equal to 25%. Combinations of the above ranges are also possible (e.g., greater than or equal to 25% and less than or equal to 75%). Other ranges are also possible.

[0043] As previously described with reference to the accompanying drawings, in some embodiments, an iron alloy coating is deposited onto a circuit board (e.g., a printed circuit board), for example, onto a trace (e.g., a first trace of a plurality of traces) of the circuit board. In some embodiments, one or more traces can be formed in the circuit board by etching. In some embodiments, the traces are formed by printing the traces on a substrate (e.g., a flexible substrate, a polymer substrate). And while for some embodiments, the coating is applied to the traces, it should be understood that the coating need not be applied to the traces and, for example, can be applied to a circuit board (or some other object) that does not have traces. As another example, in one embodiment, a coating (e.g., a first coating) is applied to the circuit board, then a trace (e.g., the first trace) is applied to the circuit board, and another coating (e.g., a second coating) is applied to the trace, such that the coating can be applied to the traces and can also be applied to different portions of the circuit board that do not have traces. In some embodiments, one or more of the plurality of traces has a particular shape (e.g., a coil), and the coating is applied such that exposed portions of the trace are coated while underlying portions of the trace remain uncoated (e.g., such that at least one surface of the trace is uncoated).

[0044] In some embodiments, a circuit board (e.g., a PCB) comprises one or more metals. For example, in some embodiments, the circuit board comprises copper and / or gold. One or more traces (e.g., a first trace, a plurality of traces) may be formed in the circuit board, and (at least some) of the metal may be exposed. For example, a surface (e.g., a top surface) of the circuit board may be etched to expose the one or more metals. In some such embodiments, a coating is applied to at least a portion of the metal. In some such embodiments, the coating may increase or otherwise enhance the properties of the metal (e.g., the magnetic properties of the metal).

[0045] In some embodiments, the circuit includes a trace comprising a conductive material. For example, the trace can be deposited (e.g., printed) on a substrate, wherein the trace comprises a conductive material, and a coating can be applied to the trace. Conductive materials include metals and conductive polymers. Non-limiting examples of conductive metals include copper (e.g., copper foil), silver (e.g., silver paste), gold, and platinum. Non-limiting examples of conductive polymers include polypyrrole, polyaniline, polyphenylene, polythiophene, and polyacetylene. Other conductive polymers are also possible.

[0046] For some embodiments, the coating is applied as a film on a flexible substrate (e.g., a flexible PCB). In some such embodiments, the coating may also have a degree of flexibility to bend with the flexible substrate.

[0047] In some embodiments, the thickness of the coating deposited on the trace (e.g., the trace of the flexible substrate or PCB) has a specific thickness. In some embodiments, the thickness of the coating is less than or equal to 1 μm, less than or equal to 0.9 μm, less than or equal to 0.8 μm, less than or equal to 0.7 μm, less than or equal to 0.6 μm, less than or equal to 0.5 μm, less than or equal to 0.4 μm, less than or equal to 0.3 μm, less than or equal to 0.2 μm, or less than or equal to 0.1 μm. In some embodiments, the thickness of the coating is greater than or equal to 0.1 μm, greater than or equal to 0.2 μm, greater than or equal to 0.3 μm, greater than or equal to 0.4 μm, greater than or equal to 0.5 μm, greater than or equal to 0.6 μm, greater than or equal to 0.7 μm, greater than or equal to 0.8 μm, greater than or equal to 0.9 μm, or greater than or equal to 1 μm. Combinations of the above ranges are also possible (e.g., less than or equal to 1 μm and greater than or equal to 0.1 μm). Other ranges are possible.For embodiments in which a coating is applied to more than one trace, each trace may have a thickness within the above ranges.

[0048] In some embodiments, the coating further comprises a dielectric layer and / or an adhesive layer. A dielectric layer is a layer comprising a dielectric material. Dielectric material will be understood to have its ordinary meaning in the art, referring to a material that is an electrical insulator that can be polarized by an applied electric field. Non-limiting examples of dielectric materials include ceramics (e.g., porcelain, silicates), glass, plastic, and oxides of various metals (e.g., iron oxide, aluminum oxide). An adhesive layer can be used to bond layers together or can be advantageous in winding or coiling wire. For example, in one embodiment, the coating comprises a first iron alloy layer, an adhesive layer, and a second iron alloy layer, wherein the adhesive layer is between the first and second iron alloy layers. Other arrangements of the iron alloy layer and the adhesive layer and / or dielectric layer are of course possible. Non-limiting examples of adhesive layers include glue, epoxy resin, and polymer adhesives.

[0049] In some embodiments, electrodeposition can be used to form a coating (e.g., an iron alloy coating) or layer on a surface (e.g., the surface of a PCB board, the traces within the surface of a PCB board). Electrodeposition generally involves depositing (e.g., electroplating) a material (e.g., an electroplated object) on a substrate (e.g., the metal of a substrate) by contacting the substrate with an electrodeposition bath and allowing an electric current to flow through the electrodeposition bath between two electrodes, i.e., due to the potential difference between the two electrodes. For example, method described herein can involve providing an anode, a cathode, an electrodeposition bath (also referred to as an electrodeposition fluid) associated with (e.g., contacting) the anode and cathode, and a power supply connected to the anode and cathode. In some cases, the power supply can be driven to generate a waveform for producing a layer, as more fully described below.

[0050] Typically, a coating or layer (e.g., an iron alloy coating) can be applied using separate electrodeposition baths. In some cases, the individual articles can be connected so that they can be sequentially exposed to separate electrodeposition baths, such as in a reel-to-reel process. For example, the articles can be connected to a common conductive substrate (e.g., a strip). In some embodiments, the electrodeposition baths can each be associated with a separate anode, and the individual articles connected to each other can typically be connected to a cathode.

[0051] Various electrochemical baths can be used to carry out the electrodeposition process. In certain embodiments, the electrochemical bath comprises at least an iron ion species. The oxidation state of the iron ion species can be divalent, trivalent, or any other oxidation state that iron can achieve in its compound. In some embodiments, other metals can be present. These metals can be selected from cobalt, copper, magnesium, manganese, nickel, and zinc. Other metals can be suitable. Typically, metal salts of Fe, Co, Cu, Mg, Mn, Ni, or Zn can be used as the source of the metal species. For example, these salts can be metal chlorides (e.g., FeCl ), metal bromides, metal sulfates, metal nitrates, metal phosphates. Other metal salts or molecular species can be suitable, as this disclosure is not limited thereto. Those of ordinary skill in the art will be able to determine other suitable metal salts for electrodeposition.

[0052] Several embodiments utilize an electrodeposition bath that may include at least one component that does not include a metal species but may further aid the electrodeposition process. Non-limiting examples of these components include citric acid (and its salts), tartaric acid (and its salts), acetic acid (and its salts), formic acid (and its salts), oxalic acid (and its salts), boric acid, saccharin, sodium chloride, sodium bromide, ammonium chloride, aluminum sulfate (or its hydrate), basic phosphates (e.g., Na3PO4), and nonionic surfactants. These components may be useful in complexing the metal species in solution, adjusting or buffering the pH of the electrodeposition bath, or other useful purposes. In some embodiments, other ligands or complexing agents may be present. In some embodiments, a stress-reducing compound may constitute the electrodeposition bath. In certain embodiments, a buffer may also constitute the electrodeposition bath. In certain embodiments, a conductive salt may also constitute the electrodeposition bath. Other components may constitute the bath depending on the desired composition of the ferrite layer or metal oxide layer.

[0053] In some cases, the electrodeposition bath may also contain a component to control pH, for example to control the concentration of iron hydroxide or Fe in the electrodeposition bath or the resulting article. 3+Generally, the pH can be maintained between 2 and 5. In some cases, the pH is maintained below 7 to prevent the formation of Fe(III). In some embodiments, the pH is maintained below 3.5 to prevent the formation of iron hydroxides.

[0054] In some embodiments, the coating of the present invention can be formed by direct current (DC) plating, pulse current plating, reverse pulse current plating or its combination.In some embodiments, the coating of the present invention can be formed by direct current (DC) plating, pulse current plating, reverse pulse current plating or its combination.In some embodiments, the coating of the present invention can be formed by direct current (DC) plating, pulse current plating, reverse pulse current plating or its combination.In some embodiments, the coating of the present invention can be formed by reverse pulse ... In some cases, the electrodeposition process may include using a waveform comprising one or more segments, where each segment involves a specific set of electrodeposition conditions (eg, current density, current duration, electrodeposition bath temperature, etc.), as described more fully below.

[0055] Various embodiments relate to electrodeposition methods in which the grain size of an electrodeposited material (e.g., a coating, metal, alloy, etc.) can be controlled. In some embodiments, selecting a particular coating (e.g., electroplated) composition (e.g., the composition of an alloy deposit) can provide a coating having a desired grain size. In some embodiments, the electrodeposition methods described herein (e.g., electrodeposition conditions) can be selected to produce a particular composition, thereby controlling the grain size of the deposited material.

[0056] In some embodiments, the coating (e.g., ferroalloy, metal layer) or its portion can be electrodeposited using direct current (DC) plating. For example, a substrate (e.g., an electrode) can be positioned to contact (e.g., immersed in) an electrodeposition bath containing one or more substances to be deposited on the substrate. A constant steady-state current can be passed through the electrodeposition bath to produce a coating or its portion on the substrate. In some embodiments, the potential applied between the electrodes (e.g., potential control or voltage control) and / or the current or current density (e.g., current control or current density control) allowed to flow can be changed. For example, pulses, oscillations, and / or other changes in voltage, potential, current, and / or current density can be incorporated during the electrodeposition process. In some embodiments, pulses of controlled voltage can be alternated with pulses of controlled current or current density. In some embodiments, pulsed current electrodeposition, reverse pulsed current electrodeposition, or a combination thereof can be used to form (e.g., electrodeposited) a coating.

[0057] In some cases, a bipolar waveform comprising at least one forward pulse and at least one reverse pulse (i.e., a "reverse pulse train") may be used. In some embodiments, at least one reverse pulse immediately follows at least one forward pulse. In some embodiments, at least one forward pulse immediately follows at least one reverse pulse. In some cases, a bipolar waveform comprises multiple forward and reverse pulses. Some embodiments may include a bipolar waveform comprising multiple forward and reverse pulses, each pulse having a specific current density and duration. In some cases, using a reverse pulse train may allow for tuning of the composition and / or grain size of the resulting coating.

[0058] The articles described herein (e.g., coated wires, coils) can be used as wireless charging devices. As described herein, wireless charging (or inductive charging, used interchangeably herein) utilizes electromagnetic fields to transfer energy between two objects through electromagnetic induction. This is achieved using a receiving device and a transmitting device. The transmitting device is typically stationary and remains plugged into a standard wall outlet and includes a transmitting coil. The receiving device is typically the device whose battery is to be recharged (e.g., a cell phone, smartphone, tablet, laptop, consumer electronic device) and includes a receiving coil. Energy is transmitted to the electrical device via inductive coupling (i.e., from the transmitting coil to the receiving coil), which can then use the energy to charge the battery or operate the device. Inductive charging uses an inductive coil (i.e., the transmitting coil) to generate an alternating electromagnetic field within a charging base. A second inductive coil (the receiving coil) in the portable device receives the power from the electromagnetic field and converts it back into electrical current to charge the battery. Two inductive coils in close proximity combine to form a power transformer. When inductive charging systems use resonant inductive coupling, greater distances between the transmitting and receiving coils can be achieved.

[0059] The articles described herein can be suitable for a variety of applications. For example, in some embodiments, the articles are printed circuit boards, flexible circuit boards, flexible films, flexible circuit boards, and / or inductor coils that include a coating (e.g., an iron alloy coating) as described above. Of course, other applications are possible, as the present disclosure is not limited thereto.

[0060] The following examples are intended to illustrate certain embodiments of the invention, but do not exemplify the full scope of the invention.

[0061] Example 1

[0062] The following example describes coating the traces of a portion of a flexible PCB with a ternary iron alloy comprising a mixture of iron, nickel, and cobalt.

[0063] Samples of wire were electroplated with a 1 µm layer of NiFeCo alloy with several compositions shown in the table below. Using a Keysight E4980A LCR meter, 1 meter of each coated wire was compared to 1 meter of uncoated wire over the frequency range of 100 kHz to 2 MHz. The inductive response was consistent over this range. The results for the 2 MHz data are tabulated below:

[0064] Table 1 - Ferroalloy compositions of samples 1 to 6

[0065]

[0066] Unexpectedly, the maximum relative inductance response achieved for these samples is outside the optimal composition range predicted by the literature for alloys of iron, nickel, and cobalt.

[0067] Although several embodiments of the present disclosure have been described and illustrated herein, a person of ordinary skill in the art will readily conceive of a variety of other ways and / or structures for performing the functions described herein and / or obtaining the results and / or one or more advantages described herein, and each of such variations and / or modifications is considered to be within the scope of the present disclosure. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and that actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications in which the teachings of the present disclosure are used. Those skilled in the art will recognize or be able to determine many equivalents to the specific embodiments of the present invention described herein using only routine experimentation. Therefore, it should be understood that the foregoing embodiments are presented by way of example only, and within the scope of the appended claims and their equivalents, the present invention may be practiced in ways other than as specifically described and claimed. The present disclosure relates to each individual feature, system, article, material, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, and / or methods is included within the scope of the present disclosure if they are not inconsistent with each other.

Claims

1. A product comprising: Coil; and a metallic coating comprising an iron alloy deposited on said coil, At least a portion of the surface of the coil does not contain the metal coating.

2. The article of claim 1 , wherein the ferroalloy comprises 20% by weight or more and / or 50% by weight or less of nickel (Ni), 20% by weight or more and / or 50% by weight or less of cobalt (Co), and / or optionally another metal, wherein the remainder of the ferroalloy is iron (Fe).

3. The article according to any one of claims 1 to 2, wherein the thickness of the metal coating is less than or equal to 1 micrometer and / or greater than or equal to 0.1 micrometer.

4. The article of any one of claims 1 to 3, wherein the ferrous alloy has a crystal structure comprising a body-centered cubic unit cell and / or a face-centered cubic unit cell.

5. The article of any one of claims 1 to 4, wherein the ferrous alloy has a crystal structure comprising hexagonal close-packed unit cells.

6. The article according to any one of claims 1 to 5, wherein greater than or equal to 25% and / or less than or equal to 75% of the surface of the coil is coated with the metal coating.

7. The article according to any one of claims 1 to 6, wherein greater than or equal to 25% and / or less than or equal to 75% of the surface of the coil is free of the metal coating.

8. The article according to any one of claims 1 to 7, wherein the article is a printed circuit board, a flexible film, a flexible circuit board, and / or an inductor coil.

9. A circuit board comprising: a plurality of traces on the circuit board, and a metallic coating comprising an iron alloy deposited on a first trace of the plurality of traces; A portion of the first trace is free of the metal coating.

10. The circuit board of claim 9, wherein the plurality of traces comprise copper, the metal coating is deposited on the copper of the first trace, and wherein at least a portion of the copper of the first trace is free of the metal coating.

11. The circuit board of any one of claims 9 to 11, wherein each trace of the plurality of traces comprises three or more surfaces, and wherein at least one surface of the first trace is free of the metal coating.

12. The circuit board of any one of claims 9 to 12, wherein one or more of the plurality of traces are shaped as a coil.

13. The circuit board of any one of claims 9 to 12, wherein the first trace is shaped as a coil.

14. A method for manufacturing a coil on a circuit board, the method comprising: forming a first trace on the circuit board; as well as coating the first trace with a metallic coating comprising an iron alloy, At least a portion of the first trace is free of the metal coating. The method of claim 14 , wherein at least one surface of the first trace is free of the metal coating.

16. The method of any one of claims 14 to 15, further comprising forming a plurality of traces on the circuit board.

17. The method of any one of claims 14 to 16, wherein any of the forming steps comprises etching the circuit board.

18. A method according to any one of claims 14 to 17, wherein at least one track is shaped into a coil.

19. The method of any one of claims 14 to 18, wherein coating the circuit board comprises performing electroplating on the circuit board.

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