Card antenna and method for manufacturing a card containing the same

Abstract

A method of manufacturing a multi-layer transaction card includes steps of laminating a plurality of layers together to form a card body having a top layer and at least one inductive coupling antenna layer. The inductive coupling antenna layer has an antenna winding and a conductive pad surrounded by but unattached to the antenna winding. The method includes commencing milling a pocket from the top layer toward the inductive coupling antenna layer using a milling machine having a mill tip and ceasing milling the pocket when the mill tip contacts the conductive pad. A method for increasing power transfer between a card reader and selected electronic portions of a transaction card includes providing the RF antenna to receive power from the card reader, the RF antenna including the antenna winding and the conductive pad and connecting the antenna winding the selected electronic portions in order to provide power.

Description

[0001] CARD ANTENNA AND METHOD FOR MANUFACTURING A CARD CONTAINING

[0002] THE SAME

[0003] CROSS-REFERENCE TO RELATED APPLICATION

[0004] This application is related and claims priority to U.S. Provisional Patent Application No. 63 / 728,233, filed on December 5, 2024, titled "CARD ANTENNA AND METHOD FOR MANUFACTURING A CARD CONTAINING THE SAME," the contents of which are incorporated herein by reference in their entirety for all purposes.

[0005] BACKGROUND OF THE INVENTION

[0006] Smart cards are in wide use, including but not limited to in payment applications, such as for use as debit and credit cards (sometimes referred to generally as "transaction cards"), but not limited to any particular type of use. In general, smart cards are well suited for any type of application that requires an authentication communication or other communication between the card and a card reader.

[0007] Generally, a smart card is a card that includes embedded electronic circuitry such as an integrated circuit (IC) chip that connects or couples to a card reader with direct physical contact and / or with a remote contactless radio frequency interface. Smart cards may be (1) contact only, (2) contactless only, and (3) dual interface, with both contact and contactless functionality.

[0008] A "contact" smart card includes an IC chip connected to a conductive contact plate on which are mounted a number of physical contact pads (typically gold plated) located generally on the top surface of the card. A contact smart card is inserted into a contact type smart card reader and transmits commands, data, and card status over the physical contact pads.

[0009] A "contactless" smartcard contains an IC chip and a card antenna and is configured for coupling of RF signals between the smart card's IC chip and the antenna of a card reader. This permits wireless (e.g., radio frequencies (RF)) communication between the card and a card reader with no direct electrical contact between the card and the card reader. A contactless smart card requires only close proximity to a reader. Both the reader and the smart card have antennae, and the two communicate using RF over a contactless link. Most contactless cards also derive power for the internal chip from electromagnetic signals emitted by the card reader. The range of operation may vary from less than an inch to several inches. The antenna in the card may comprise a discrete antenna layer 800 comprising metal antenna windings 802 disposed in or on a non-metal layer 804, as shown in FIGS. 1A and IB. The antenna windings 802 may include outer windings 810 adjacent an outer periphery of the card, and inner windings 812 aligned with a hole in the card for receiving embedded electronics, such as an IC chip transaction module, as described further below. Although not shown, the inner and outer windings are connected to one another, and the antenna may be connected to an electrical circuit. For example, the antenna may be physically or inductively connected to a transaction module or to a device that receives power collected by the antenna.

[0010] A "dual-interface" smart card has, typically, a single IC chip (but could have two or more, such as, for example, embodiments in which one chip is for payment, another is for power harvesting, and another may be for control of some other powered function, such as lighting) and includes both contact and contactless interfaces. With dual-interface cards, it is possible to access the IC chip(s) using a contact and / or a contactless interface.

[0011] It has also become very desirable and fashionable to make cards with one or more metal layers. A metal layer provides a desirable weight and a decorative pattern and / or reflective surface enhancing the card's appearance and aesthetic value. This is especially desirable for use by high-end customers. It is therefore desirable to make dual interface (contacts and contactless) smart cards having a metal layer.

[0012] Although the invention is not limited to any particular materials of construction, metal transaction cards present unique challenges when embedding electronics into the card to provide any number of functions. Functionalities provided by such embedded electronics may include, without limitation, functions that permit use of biometrics, one time passcodes, a display (e.g. liquid crystal diode (LCD) or e-ink) for displaying messages or product offerings, an indicator (e.g. a light, such as an LED) that activates when functions of the card are in operation (such as when the card is physically or inductively connected to a reader and being read), connectivity to the Internet to permit the card to participate in the Internet of Things (loT), or any other functionality desired. One illustrative example of a use for embedded electronics in a card is to configure a card to be operated by either a contact card reader or an inductive (contactless) card reader. To accommodate these electronic components, the metal is machined into various geometries, and then the component is placed in the cavity and left exposed or hidden under a printed sheet of plastic or other decorative element. The decorative element may be affixed to the card through a variety of processes such as platen lamination, contact adhesive, curable adhesives, or "push fit" or any joining method known to the art. RF shielding is often required in the cavity, further complicating card assembly while maintaining the desired aesthetic of the card.

[0013] Several problems also arise in the making of cards (e.g., metal cards, plastic cards, ceramic cards, hybrid cards, etc.) with embedded electronics. For example, during a conventional method of manufacturing a card, holes or pockets in the base (e.g. metal) layer may be filled with a non-conductive (e.g. plastic) plug for better lamination results. Later, the plug is at least partially removed (e.g. by milling away the plug) for embedding electronics (e.g. a transaction module chip) into the card. However, during this process, there is a risk of damaging the antenna layer beneath the base layer on the almost finished card. A variety of options may be considered for mitigation, including changing the placement of the antenna (which may lead to undesirable technical effects), slowing down the milling process for removing the plug (thereby reducing throughput), and / or settling for decreased yield due to damaged antennas (which negatively impacts cost and throughput). Thus, there is a desire for improvements over existing methods in manufacturing multi-layer transaction cards with embedded electronics.

[0014] SUMMARY OF THE INVENTION

[0015] One aspect of the invention is a method of manufacturing a multi-layer transaction card. The method includes a step of laminating a plurality of layers together to form a card body having a top layer and at least one inductive coupling antenna layer. The inductive coupling antenna layer has an antenna winding and a conductive pad surrounded by but unattached to the antenna winding. The method also includes a step of commencing milling a pocket from the top layer toward the inductive coupling antenna layer using a milling machine having a mill tip. Further, the method has a step of ceasing milling the pocket when the mill tip contacts the conductive pad.

[0016] Another aspect of the invention is an antenna of a transaction card. The antenna has an antenna winding a conductive pad surrounded by but unattached to the antenna winding. The antenna winding and the conductive pad each have respective first surfaces facing and spaced respective distances from an outer surface of the transaction card. The distance from the first surface of the antenna to the outer surface of the transaction card is greater than the distance from the first surface of the conductive pad to the outer surface of the transaction card.

[0017] Still another aspect of the invention is a multi-layer transaction card. The multilayer transaction card has a plurality of layers laminated together to define a card body having a top layer and at least one inductive coupling antenna layer. The inductive coupling antenna layer includes an antenna winding and a conductive pad surrounded by and unattached to the antenna winding. The antenna winding and the conductive pad each have respective first surfaces facing and spaced respective distances from the top layer. The distance from the first surface of the antenna to the top layer is greater than the distance from the first surface of the conductive pad to the top layer. The card also has a pocket extending from the top layer to the inductive coupling antenna layer. A transaction module is disposed in the pocket and configured to inductively couple to the antenna winding.

[0018] One aspect of the invention is a method for increasing power transfer between a card reader and selected electronic portions of a transaction card. Th method includes a step of providing an RF antenna configured to receive power from the card reader. The RF antenna has an antenna winding and a conductive pad comprising nonferromagnetic material surrounded by but unattached to the antenna winding. The antenna winding connected to and configured to provide power to the selected electronic portions.

[0019] BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention will be understood more completely from the following detailed description of presently preferred, but nonetheless illustrative, embodiments in accordance with the present invention, with reference being had to the accompanying drawings, which are not drawn to scale, but in which like reference characters denote like components.

[0021] FIG.1A depicts a plan view of an exemplary inductive antenna layer for use in a card.

[0022] FIG. IB depicts a cross-sectional view of the exemplary inductive antenna layer taken across line 1B-1B of FIG. 1A.

[0023] FIG. 2 depicts an exemplary method of manufacturing a multi-layer transaction card in accordance with aspects of the invention.

[0024] FIG. 3A depicts in cross section a card body comprising a plurality of layers formed via a lamination process.

[0025] FIG. 3B depicts an isolated cross-sectional view of the antenna layer of FIG. 3A.

[0026] FIG. 4 depicts a schematic diagram of an exemplary antenna of a transaction card in accordance with aspects of the invention.

[0027] FIG. 5 depicts an exemplary embodiment of a multi-layer transaction card in accordance with aspects of the invention.

[0028] FIG. 6A-6C depict a schematic diagrams showing an exemplary embodiment of a milling step of the method of FIG. 2.

[0029] FIG. 7 depicts an exemplary method for increasing power transfer between a card reader and selected electronic portions of a transaction card in accordance with aspects of the invention.

[0030] FIG. 8 depicts a schematic graph showing levels of antenna Q factor in accordance with prior art.

[0031] FIG. 9 depicts a schematic graph showing levels of antenna Q factor of the exemplary antenna in accordance with aspects of the invention. DETAILED DESCRIPTION

[0032] Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. Additionally, various forms and embodiments of the invention are illustrated in the figures. It will be appreciated that the combination and arrangement of some or all features of any of the embodiments with other embodiments is specifically contemplated herein. Accordingly, this detailed disclosure expressly includes the specific embodiments illustrated herein, combinations and sub-combinations of features of the illustrated embodiments, and variations of the illustrated embodiments.

[0033] In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant design features. However, it should be apparent to those skilled in the art that the present design features may be practiced without such details. In other instances, well known methods, procedures, components, and circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present design.

[0034] In general, aspects of the invention relate to transaction card antennas, multilayer transaction cards, and methods for manufacturing a multi-layer transaction card. The cards and methods described herein mitigates or prevents risk of damaging electronics (e.g. antenna) embedded in the card during manufacture of said card, thereby increasing the yield of cards during manufacture.

[0035] Referring to FIGS. 2, 3A and 3B, a method 1000 of manufacturing a multi-layer transaction card 200 includes step 1100 of laminating a plurality of layers together (e.g. using lamination platens 400) to form a card body 100. In an exemplary embodiment, the plurality of layers have at least one metal layer 110 and an antenna layer 120. The at least one metal layer 110 has at least one pocket having a non- conductive plug 130 disposed therein during the lamination step. The antenna layer 120, shown in more detail in FIG. 3B, has at least one set of internal antenna windings 122 aligned with the plug 130, and a conductive pad 124 surrounded by but unattached to the antenna winding 122.

[0036] In the exemplary embodiment depicted in FIG. 3A, card body 100 comprises at least metal layer 110, antenna layer 120, top protective layer 102, and bottom protective layer 104. The card 200 is not limited to any particular number of layers, and the relative thicknesses of the layers as depicted are not to scale. Each layer as depicted may comprise a plurality of sub-layers. More or fewer layers may be present. Additional layers may include, without limitation, adhesive layers (not shown) comprising a polymer film covered on both sides with an adhesive disposed between adjacent layers. In embodiments, a shielding layer (e.g. ferrite) may be disposed between the metal layer 110 and the antenna layer 120. Additional layers may include laminates (e.g. ceramic, patinated metal, leather, wood, anodized layers, etc.), adhesive layers, printed content, or coatings (including but not limited to a ceramic coating), without limitation. In an exemplary embodiment, as shown in FIG. 4, portions of the antenna 120 comprise the antenna winding 122 and a conductive pad 124 surrounded by but unattached to the antenna winding 122. The conductive pad 124 may comprise non-ferromagnetic material.

[0037] The internal antenna windings 122 and the conductive pad 124 each have respective surfaces facing and spaced respective distances from an outer surface of the transaction card 200 (the top surface of top layer 102, as depicted in FIG. 3A, for example). In an exemplary embodiment, the antenna winding 122 has a top surface spaced a distance (DI) to the top or outer surface 114 of the transaction card 200. The conductive pad 124 has a top surface 126 spaced a distance (D2) to the outer surface 114 of the transaction card 200 (e.g. the top surface of top protective layer 102). The distance (DI) from the first surface of the antenna 122 to the outer surface 114 of the transaction card 200 is greater than the distance (D2) from the first surface 126 of the conductive pad 124 to the outer surface 114 of the transaction card 200 (e.g., DI > D2). This relationship between DI and D2 ensures that, as depicted in FIGS. 6A-6C, the milling tip 310 first makes contact with the top surface 126 of pad 124 prior to coming in contact with antenna windings 122.

[0038] In an exemplary embodiment, portions of the antenna layer 120 comprise an outer antenna winding 121 and an inner antenna winding 122 connected to one another to form a singular conductor. Although depicted in FIG. 3B with the antenna windings 121,122 on a bottom surface of antenna layer 120 and the pad 124 disposed on the top surface of the antenna layer 120, it should be understood that the antenna windings 121, 122 may be disposed on a top and / or bottom of the antenna layer 120 (some embodiments may have windings on both sides), or inset within the antenna layer, and the pad 124 may be disposed on the top or fully or partially inset from the top or bottom surface of the antenna layer 120. The key is that the top-facing surface of the pad 124 (where "top" refers to the side from which the milling operation is conducted) is closer to the top surface of the card 200 than a top surface of the antenna windings 121,122. Notably, in embodiments in which the antenna windings 121, 122 are on a top surface of the antenna layer 120, at least one non-conductive layer is disposed between the metal layer 110 and the metal antenna windings 121, 122.

[0039] In another embodiment, depicted in FIG. 5, metal layer 510 may have multiple openings for receiving plugs 530a, 530b during the lamination step (e.g., lamination step 1100). Antenna layer 520 includes outer antenna windings 121 and two sets of inner windings 122a, 122b having a conductive pad 124a, 124b, respectively, surrounded by but unattached to the antenna windings 122a, 122b. As depicted in FIG. 5, a first set of inner antenna windings 122a is disposed beneath plug 530a disposed in a first through-hole in metal layer 510, and a second set of inner antenna windings 122b is disposed beneath plug 530b disposed in a second through-hole in in metal layer 510. In accordance with the method 1000 as described herein, plug 530a is milled to create an opening to receive transaction module 116. Likewise, plug 530b is milled to create an opening to receive additional embedded electronics, such as an LED display 142.

[0040] Antenna windings 122a and corresponding conductive pad 124a, and windings 124b and corresponding conductive pad 124b each have respective surfaces facing and spaced respective distances from an outer surface of the transaction card 200 (the top surface of top layer 102, as depicted in FIG. 5). In an exemplary embodiment, the antenna winding 122a has a top surface spaced a distance (DI) to the top surface 114 of the transaction card 200. The conductive pad 124a has a top surface 126 spaced a distance (D2) to the outer surface 114 of the transaction card 200 (e.g. the top surface of top protective layer 102). Likewise, windings 122b have a distance (D3) and pad 124b has a distance (D4) from the top surface of the card 500. Just as the distance (DI) from the first surface of the antenna 122a to the outer surface 114 of the transaction card 200 is greater than the distance (D2) from the first surface 126 of the conductive pad 124a to the outer surface 114 of the transaction card 200 (e.g., DI > D2), so is D3>D4.

[0041] Thus, method 1000 includes step 1200 of commencing milling a pocket from a top or outer surface toward the antenna layer 1200. In an exemplary embodiment, step 1200 comprises commencing milling a pocket 112 using a milling machine 300 having a mill tip 310. Method 1000 includes step 1300 of ceasing milling the pocket 112 when the mill tip 310 contacts the conductive pad 124. Additional details of milling steps 1200 or 1300 are discussed below.

[0042] As shown in FIG. 6A-6C, milling machine 300 having mill tip 310 is configured with conductor sensing capabilities, such that the mill tip 310 is configured to approach a conductive target, such as conductive pad 124 as depicted in FIGS. 6A and 6B, and stops its approach upon contact with a surface of the conductive target as shown in FIG. 6C. In this way, damage to the underlying layer or a layer which is relatively positioned a further distance away from the mill tip 310 (and structures on that layer, such as antenna windings 122) when the mill tip 310 makes contact with the conductive pad 124, is restricted or prevented.

[0043] Card 500 includes a pocket 112 extending from the top layer 502 to the inductive coupling antenna layer 520. Transaction module 116 is disposed in the pocket 112 and configured to inductively couple to the antenna windings 122a. Most embodiments also include an embedded integrated circuit (not shown) connected to contacts (e.g. as disposed on transponder module 116) configured to be read by a card reader and the embedded antenna 122 to permit use with contact-based and / or contactless card readers. The integrated circuit and connected contacts may be embedded in the metal card body by any method known in the art, such as described in U.S. Pat. No. 9,390,366, titled "METAL SMART CARD WITH DUAL INTERFACE CAPABILITY," assigned to the common assignee of the present invention, incorporated herein by reference. In operation, the antenna winding 122 is designed to capture radio frequency (RF) energy generated by an associated card reader (not shown) and to communicate with the card reader. By design, the antenna winding 122 is sufficiently close to couple inductively with the antenna of the transponder module 116.

[0044] In still another exemplary embodiment, a method for increasing power transfer between a card reader and selected electronic portions of a transaction card is provided.

[0045] Method 2000 includes a step 2100 of providing a radio frequency (RF) antenna configured to receive power from a card reader. A non-limiting example of the RF antenna comprises the antenna windings 122b and the conductive pad 124b, as described and shown above. Antenna winding 122b and the conductive pad 124b are substantially surrounded by the at least one metal layer 110. By "substantially surrounded," it is meant that that at least one metal layer 110 may optionally have at least one discontinuity extending from the periphery of the card 200 to at least one opening (e.g. pocket 112 configured to receive transponder module 116) in the metal layer 110. The at last one discontinuity may also improve RF performance relative to a card with an absence of the at last one discontinuity. Exemplary embodiments of the at least one discontinuity are as described in the foregoing, and in U.S. Pat. No. 10,762,412, titled "DI CAPACITIVE EMBEDDED METAL CARD," assigned to the common assignee of the present invention, and incorporated herein by reference. The slit or discontinuity may have any geometry described in the '412 patent and related applications, or any geometry disclosed in the foregoing references. Conductive pad 124b includes a non-ferromagnetic material surrounded by but unattached to the antenna winding 122b. The addition of conductive pad 124b (e.g. in roughly a center portion of layer 120 relative to the antenna winding 122b) increases the capabilities of the RF antenna 122b to harvest RF power. As best shown by comparing FIGS. 8 and 9, the antenna Q factor of the peak around the target frequency, which is illustrated in FIG. 9, decreases (relative to the peak of prior art antennas shown in FIG. 8) on the power spectrum of the antenna. In this way, the inventive RF antenna 122b has a wide range of frequencies via which it may receive signals, thereby increasing the robustness of the antenna 122b to harvest RF power. This configuration is advantageous in cards having embedded electronics, such as light emitting diodes (LEDs) 142, as described further below.

[0046] Accordingly, method 2000 method 2000 includes step 2200 of connecting the antenna winding 122b to selected electronic portions of card 500. In an exemplary embodiment, selected electronic portions of card 500 depend on the functionality desired for the card. For example, the components may include a printed circuit board (PCB), a keypad for entry of information, a power source comprising a battery or any other source of power suitable for including in a card, such as a photovoltaic cell, or a circuit (e.g. comprising capacitor relays) that harvests electricity from radio frequency (RF) signals, as are known in the art. Methods for making PCBs suitable for insertion in a card body, including PCBs comprising flexible substrates, are well known in the art and the invention is not limited to any particular type of PCB, or to any particular type of functionality of the PCB (nor to any particular functionality of the other electronic components).

[0047] In an exemplary embodiment, the selected electronic portions comprise only non-communication components of the transaction card 500. Any or all of the electronic components described herein may be embedded in the card in any way known in the art, including the methods as described in U.S. Pat. No. 10,406,734, filed Oct. 18, 2018, claiming priority from U.S. application Ser. No. 16 / 320,597, filed Jan. 25, 2019, both titled "OVERMOLDED ELECTRONIC COMPONENTS FOR TRANSACTION CARDS AND METHODS OF MAKING THEREOF," both assigned to the common assignee of the present invention and incorporated herein by reference.

[0048] In one non-limiting example, the selected electronic portions comprise one or more LEDs 142 configured to provide an illumination of at least a portion of the card 500 visible to a user of the card 500 when the antenna 122 is receiving power from the card reader (not shown). Exemplary processes for embedding LEDs for insertion in a metal card body are described in U.S. Pat. No. 10,885,419, titled "TRANSACTION CARD WITH EMBEDDED ELECTRONIC COMPONENTS AND PROCESS FOR MANUFACTURE," claiming priority from U.S. Application Ser. No. 62 / 555,367, filed Sep. 7, 2017, and U.S. Pat. No. 11,151,437, titled "METAL, CERAMIC, OR CERAMIC-COATED TRANSACTION CARD WITH WINDOW OR WINDOW PATTERN AND OPTIONAL BACKLIGHTING," all of which are assigned to the common assignee of the present invention and incorporated herein by reference. In other embodiments, the LEDs (or LCD or other type of display) may provide a dynamic card verification value (CVV), as described in U.S. Application Ser. No. 18 / 037,465, filed Nov. 17, 2021, titled "METHOD AND SYSTEM FOR GENERATING A DYNAMIC CARD VERIFICATION VALUE FOR PROCESSING A TRANSACTION," assigned to the common assignee of the present invention and incorporated herein by reference.

[0049] Although depicted in a single embodiment in FIG. 5, comprising both a transaction module 116 and a second set of embedded electronics having the advantages as discussed herein for harvesting power, it should be understood that some card embodiments may have only non-transaction-module embedded electronics featuring the conductive pad 124 as described herein. Additionally, while the advantages of including the conductive pad 124 for improving card yield in a milling operation have been described herein, it should be understood that the advantages in improving power harvesting may be a sole motivator for including the pad 124 in some embodiments, especially those in which the milling operation concerns are addressed in another manner.

[0050] Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.

Claims

AMENDED CLAIMS received by the International Bureau on 19 May 2026 (19.05.2026)[Claim 1] A method of manufacturing a multi-layer transaction card, the method comprising: laminating a plurality of layers together to form a card body having a top layer and at least one inductive coupling antenna layer, the inductive coupling antenna layer comprising an antenna winding and a conductive pad surrounded by but unattached to the antenna winding; commencing milling a pocket from the top layer toward the inductive coupling antenna layer using a milling machine having a mill tip; ceasing milling the pocket when the mill tip contacts the conductive pad.[Claim 2] An antenna of a transaction card, the antenna comprising an antenna winding a conductive pad surrounded by but unattached to the antenna winding, the antenna winding and the conductive pad each having respective first surfaces facing and spaced respective distances from an outer surface of the transaction card, wherein the distance from the first surface of the antenna to the outer surface of the transaction card is greater than the distance from the first surface of the conductive pad to the outer surface of the transaction card.[Claim 3] A multi-layer transaction card comprising: a plurality of layers laminated together to define a card body having a top layer and at least one inductive coupling antenna layer, the inductive coupling antenna layer comprising an antenna winding and a conductive pad surrounded by and unattached to the antenna winding, the antenna winding and the conductive pad each having respective first surfaces facing and spaced respective distances from the top layer, wherein the distance from the first surface of the antenna to the top layer is greater than the distance from the first surface of the conductive pad to the top layer; and a pocket extending from the top layer to the inductive coupling antenna layer; and a transaction module disposed in the pocket and configured to inductively couple to the antenna winding.[Claim 4] A method for increasing power transfer between a card reader and selected electronic portions of a transaction card: providing an RF antenna configured to receive power from the card reader, wherein the RF antenna comprises an antenna winding and aconductive pad comprising non-ferromagnetic material surrounded by but unattached to the antenna winding, the antenna winding connected to and configured to provide power to the selected electronic portions.[Claim 5] The method of claim 4, wherein the selected electronic portions comprise only non-communication components of the transaction card.[Claim 6] The method of claim 5, wherein the selected electronic portions comprise one or more LEDs configured to provide an illumination of at least a portion of the card visible to a user of the card when the antenna is receiving power from the card reader.[Claim 7] The method of claim 1, wherein at least one layer of the transaction card comprises a metal layer.[Claim 8] The antenna of claim 2, wherein at least one layer of the transaction card comprises a metal layer.[Claim 9] The multi-layer transaction card of claim 3, wherein at least one layer of the transaction card comprises a metal layer.[Claim 10] The method of claim 4, wherein at least one layer of the transaction card comprises a metal layer.[Claim 11] The method of claim 1, wherein the conductive pad comprises nonferromagnetic material.[Claim 12] The antenna of claim 2, wherein the conductive pad comprises nonferromagnetic material.[Claim 13] The multi-layer transaction card of claim 3, wherein the conductive pad comprises non-ferromagnetic material.[Claim 14] The antenna of claim 8, wherein the antenna winding and conductive pad are substantially surrounded by the at least one metal layer.[Claim 15] The antenna of claim 12, wherein the antenna winding and conductive pad are substantially surrounded by the at least one metal layer.[Claim 16] The multi-layer transaction card of claim 9, further comprising at least one non-conductive layer disposed between the antenna winding and the metal layer.[Claim 17] The multi-layer transaction card of claim 16, wherein the antenna winding includes at least two sets of inner antenna windings, each having a respective conductive pad surrounded by but unattached to the at least two sets of inner windings.[Claim 18] The multi-layer transaction card of claim 17, wherein the metal layer includes plural through-holes configured for receiving a respective Plug.[Claim 19] The multi-layer transaction card of claim 18, wherein a first set of the inner antenna windings is disposed beneath a first plug disposed in a first through-hole in the metal layer and a second set of the inner antenna windings is disposed beneath a second plug disposed in a second through-hole in the metal layer.[Claim 20] The multi-layer transaction card of claim 18, wherein the first plug is milled to form the pocket for receiving the transaction module, and the second plug is milled to form another opening to receive at least one electronic component.

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