Single-interface strip-based dual-interface function smart card and manufacturing method thereof

Abstract

The application provides a single-interface strip-based dual-interface function smart card and a manufacturing method thereof. The method comprises the following steps: filling and solidifying the LA electrode groove and the LB electrode groove of the single-interface strip with conductive material; performing flat treatment on the surface of the conductive material formed in the LA electrode groove and the LB electrode groove after solidification, to form LA conductive protrusions and LB conductive protrusions; milling the copper wire surface coating layer at the positions corresponding to the LA conductive protrusions and the LB conductive protrusions on the card body Inlay antenna; and hot-press connecting the processed single-interface strip and the card body Inlay antenna by using ACF conductive adhesive film. The LA / LB electrode groove is filled and flattened by using conductive material, the contact risk caused by uneven structure is eliminated, stable electrical connection between the LA / LB conductive protrusions of the single-interface strip and the card body Inlay antenna is realized by using ACF conductive adhesive, and batch production of low-cost and high-reliability single-interface strip dual-interface cards is realized.

Description

Technical Field

[0001] This application relates to the field of mobile communication technology, and in particular to a dual-interface smart card based on a single-interface strip and its manufacturing method. Background Technology

[0002] Existing dual-interface smart chip cards (IC cards) possess both contact and contactless read / write capabilities. Dual-interface IC modules on the market primarily utilize specialized dual-interface strip packaging. This dual-interface strip contains two layers of copper foil: a contact side (hereinafter referred to as "front") for the contact interface and a solder side (or bonding side, cover, hereinafter referred to as "soldering side") for the contactless interface. Therefore, it is necessary to manufacture both layers of copper foil on the strip and perform etching, nickel plating, and gold plating processes on them. This results in dual-interface strips being more expensive than single-interface strips.

[0003] However, all the aforementioned processes utilize dual-interface strips. Dual-interface strips have copper foil layers on both sides of the substrate—the front side forms contact points conforming to ISO 7816 standards, while the back side has dedicated pads or circuitry for connecting contactless antennas. Both sides require metallization processes such as copper bonding, nickel plating, and gold plating, resulting in high material and processing costs. Currently, all dual-interface composite cards use dual-interface strips, and both sides of the strip require copper bonding, nickel plating, and gold plating, leading to high material and processing costs.

[0004] Patent applications CN108764436B and CN106960240B also disclose methods for fabricating dual-interface smart cards using single-interface stripes. The techniques employed involve punching and bridging circuit soldering, but processes like wire pick-and-spot soldering are challenging to implement. Signal and power transmission is achieved through direct physical contact between the card body's inlay antenna and the LA (antenna A end) / LB (antenna B end) electrodes on the back of the module. Solder sheet soldering and conductive post processes are prone to poor contact, resulting in low product yield. Conventional wire pick-and-spot soldering offers relatively better reliability, but it is more difficult to control and requires highly skilled equipment and personnel.

[0005] Therefore, the urgent technical problem to be solved is: how to provide a dual-interface smart card based on a single-interface strip and its manufacturing method, to solve the contact problems caused by the uneven surface of the single-interface strip, and the problem of unstable electrical connection between the LA / LB electrodes of the single-interface strip and the inlay antenna of the card body, so as to achieve low-cost, high-reliability mass production of dual-interface cards with a single-interface strip. Summary of the Invention

[0006] The purpose of this application is to provide a dual-interface smart card based on a single-interface strip and its manufacturing method. The conductive material is used to fill and flatten the LA / LB electrode grooves of the single-interface strip to eliminate the contact risk caused by the unevenness of the single-interface strip structure. ACF conductive adhesive is used to achieve a stable electrical connection between the LA / LB electrodes of the single-interface strip and the inlay antenna of the card body, so as to realize the mass production of low-cost and high-reliability single-interface strip dual-interface cards.

[0007] To achieve the above objectives, as a first aspect of this application, this application provides a method for manufacturing a dual-interface smart card based on a single-interface strip, characterized in that the method includes: filling and curing the LA electrode groove and LB electrode groove of the single-interface strip with a conductive material; The conductive material surfaces formed after curing in the LA electrode groove and LB electrode groove are flattened to form LA conductive protrusions and LB conductive protrusions. The surfaces of the LA conductive protrusions and LB conductive protrusions are flat and protrude from the surface of the single interface strip. The enameled layer on the copper wire surface at the positions corresponding to the LA conductive protrusion and LB conductive protrusion on the inlay antenna of the card body is milled off to form the LA conductive welding surface and the LB conductive welding surface of the antenna. The processed single-interface stripe is heat-pressed to the inlay antenna of the card body using ACF conductive adhesive film.

[0008] In one embodiment, filling and curing the LA electrode groove and LB electrode groove of the single-interface strip with a conductive material includes: filling the LA electrode groove and LB electrode groove of the single-interface strip with a conductive material. After filling with conductive material, the conductive material is cured to form LA conductive protrusions and LB conductive protrusions respectively.

[0009] In one embodiment, the surfaces of the conductive materials formed after curing in the LA electrode groove and LB electrode groove are smoothed to form LA conductive protrusions and LB conductive protrusions, including: The LA and LB conductive protrusions after being aligned and cured are milled using a CNC milling cutter to remove excess conductive material that exceeds the predetermined range above the surface of the single interface strip. Remove conductive powder debris generated during milling; Conduct resistance testing is performed on the conductive protrusions.

[0010] In one embodiment, milling away the enameled layer on the copper wire surface at the positions corresponding to the LA conductive protrusion and LB conductive protrusion on the inlay antenna of the card body to form the antenna LA conductive solder surface and the antenna LB conductive solder surface includes: Fix the inlay antenna on the card body; A CNC milling cutter is used to mill grooves in the copper wires at the positions corresponding to the LA conductive protrusion and LB conductive protrusion. Based on the set milling depth parameters of the CNC milling cutter, the enameled layer in the copper wire area is removed by milling.

[0011] In one embodiment, the process of hot-pressing the processed single-interface stripe to the card body inlay antenna using an ACF conductive adhesive film includes: Align the LA conductive protrusion and LB conductive protrusion with the antenna LA conductive welding surface and antenna LB conductive welding surface of the inlay antenna of the card body; After alignment, a hot-pressing device is used to vertically press the single-interface strip and the card body inlay antenna using predetermined hot-pressing parameters.

[0012] In one embodiment, an LA electrode groove and an LB electrode groove are arranged vertically on a single interface strip.

[0013] In one embodiment, the conductive material filling the LA electrode groove and LB electrode groove extends 30-50 μm above the surface of the single-interface strip.

[0014] In one embodiment, the conductive material cured in the LA electrode groove and LB electrode groove is milled flat to 20-30 μm above the surface of the single-interface strip.

[0015] The second aspect of this application provides a dual-interface smart card using a single-interface stripe, manufactured according to the above method, including a card base and a single-interface stripe, a smart card chip, and a card body inlay antenna integrated inside the card base. The surface of the card base is provided with milled grooves, and the single-interface stripe and the smart card chip are embedded in the milled grooves. One side of the single-interface stripe is a copper foil surface, and the opposite side is a soldering surface, on which the smart card chip is mounted. The single-interface strip has a central area at its center. There are six contacts on the copper foil surface, C1-C3 and C5-C7, which surround the central area. Contact pads are provided at the positions of contacts C1, C2, C3, C5, C6, and C7. The smart card chip is provided with chip LA pads, chip LB pads, and chip contact pads that are electrically connected to the contact pads of contacts C1, C2, C3, C5, and C7. The chip LA pads and chip LB pads are electrically connected to the LA contact surface pads and LB contact surface pads located in the central area. The welding surface of the single-interface strip is also provided with LA electrode groove and LB electrode groove. The LA electrode groove and LB electrode groove are on the same axis and are arranged symmetrically above and below. The LA electrode groove is located between contacts C1 and C5 and is independent of the area where contacts C1 and C5 are located. The LB electrode groove is located between contacts C3 and C7 and is independent of the area where contacts C3 and C7 are located. The LA electrode groove and LB electrode groove are filled with conductive material. After filling with conductive material, the conductive material is cured to form LA conductive protrusion and LB conductive protrusion at the LA electrode groove and LB electrode groove. The LA conductive protrusion and LB conductive protrusion have flat surfaces and protrude from the surface of the single interface strip. The card body Inlay antenna is provided with an antenna LA conductive welding surface and an antenna LB conductive welding surface. The antenna LA conductive welding surface and the antenna LB conductive welding surface are formed by milling off the enameled layer on the copper wire surface of the card body Inlay antenna. The antenna LA conductive welding surface and the antenna LB conductive welding surface are respectively provided with LA conductive protrusion and LB conductive protrusion. The LA conductive protrusion and LB conductive protrusion are pre-attached with ACF conductive adhesive film. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body inlay antenna are vertically pressed together to electrically connect the antenna LA conductive welding surface 15A and antenna LB conductive welding surface 15B to the corresponding LA conductive protrusion and LB conductive protrusion.

[0016] A third aspect of this application provides a dual-interface smart card using a single-interface stripe, manufactured according to the above method, comprising a card base and a single-interface stripe, a smart card chip, and a card body inlay antenna integrated inside the card base. The surface of the card base is provided with milled grooves, and the single-interface stripe and the smart card chip are embedded in the milled grooves. One side of the single-interface stripe is a copper foil surface, and the opposite side is a soldering surface, on which the smart card chip is mounted. The single-interface strip has 8 pins and 8 contacts from C1 to C8. C4 extends outward to the outer regions of C3, C2, and C1; C8 extends outward to the outer regions of C7, C6, and C5, forming two extension areas. An LA electrode groove and an LB electrode groove are respectively provided on the substrate of the extension areas of C4 and C8. The LA electrode groove and the LB electrode groove are symmetrically arranged on the top and bottom. The LA electrode groove and LB electrode groove are filled with conductive material. After filling with conductive material, the conductive material is cured to form LA conductive protrusion and LB conductive protrusion at the LA electrode groove and LB electrode groove. The LA conductive protrusion and LB conductive protrusion have flat surfaces and protrude from the surface of the single interface strip. The LA conductive protrusion and LB conductive protrusion correspond to the positions of the antenna LA conductive welding surface and the antenna LB conductive welding surface. ACF conductive adhesive film is pre-applied to the LA conductive protrusion and LB conductive protrusion positions on the side of the single interface strip connected to the card body Inlay antenna. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body Inlay antenna are vertically pressed together, and the antenna LA conductive welding surface and antenna LB conductive welding surface are electrically connected to the LA conductive protrusion and LB conductive protrusion respectively.

[0017] The LA conductive protrusion and LB conductive protrusion correspond to the positions of the antenna LA conductive welding surface and the antenna LB conductive welding surface. ACF conductive adhesive film is pre-applied to the LA conductive protrusion and LB conductive protrusion positions on the side of the single interface strip connected to the card body Inlay antenna. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body Inlay antenna are vertically pressed together, and the antenna LA conductive welding surface and antenna LB conductive welding surface are electrically connected to the LA conductive protrusion and LB conductive protrusion respectively.

[0018] The beneficial effects achieved by this application are as follows: (1) In this application, the LA electrode groove and LB electrode groove of the single interface strip are filled with conductive material and milled flat to form a flat raised conductive contact surface, thereby eliminating the uneven force caused by the LA electrode groove and LB electrode groove.

[0019] (2) In this application, the LA electrode groove and LB electrode groove of the single interface strip are changed to be arranged vertically symmetrically to match the conductive welding surface of the card body Inlay antenna, thereby reducing the risk of assembly misalignment.

[0020] (3) In this application, the copper wire enameling layer is removed from the antenna LA conductive welding surface and the antenna LB conductive welding surface of the inlay antenna of the card body, exposing the copper core and eliminating insulation barrier.

[0021] (4) This application uses ACF anisotropic conductive adhesive film to heat-press bond the single interface strip and the card body Inlay antenna. The single interface strip and the card body Inlay antenna are connected with flat conductive surfaces on the top and bottom, ensuring stable vertical conduction, greatly reducing open circuits and poor connections, and improving the card production qualification rate. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 This is a flowchart illustrating a method for manufacturing a dual-interface smart card based on a single-interface strip, according to an embodiment of this application.

[0024] Figure 2 This is a schematic diagram of the structure of a 6-pin single-interface strip according to an embodiment of this application.

[0025] Figure 3 This is a schematic diagram of the structure of an 8-pin single-interface strip according to an embodiment of this application.

[0026] Figure 4This is a schematic diagram showing the distribution of the LA electrode groove and LB electrode groove in a single-interface strip according to an embodiment of this application.

[0027] Figure 5 This is a schematic diagram showing the formation of conductive protrusions in the LA electrode groove and LB electrode groove of the single-interface strip according to an embodiment of this application.

[0028] Figure 6 This is a schematic diagram of a single-interface strip structure with an ACF conductive adhesive film adhered to it, according to an embodiment of this application.

[0029] Figure 7 This is a schematic diagram of the card body inlay antenna structure according to an embodiment of this application.

[0030] Figure 8 This is a schematic diagram of the single-interface strip, card body inlay antenna layering in an embodiment of this application.

[0031] Figure 9 This is a schematic diagram of a dual-interface smart card structure based on a single-interface strip, according to an embodiment of this application.

[0032] Figure reference numerals: 1-Card body Inlay antenna, 2-Smart card chip, 3-ACF conductive adhesive film, 11-Contact surface pad, 12A-LA contact surface pad, 12B-LB contact surface pad, 13A-LA electrode groove, 13B-LB electrode groove, 14A-LA conductive protrusion, 14B-LB conductive protrusion, 15A-Antenna LA conductive soldering surface, 15B-Antenna LB conductive soldering surface, 16-Encapsulation range, 20A-Chip LA pad, 20B-Chip LB pad, 23A-8pin single-interface strip LA electrode groove, 23B-8pin single-interface strip LB electrode groove, 26-8pin single-interface strip encapsulation range, 27-Polymer gold wire, 100-6pin single-interface strip, 200-8pin single-interface strip. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0034] like Figure 1 As shown, the first embodiment of this application provides a method for manufacturing a dual-interface smart card based on a single-interface stripe, the method comprising: Step S1: Provide a single-interface strip in advance.

[0035] The single-interface strip has a copper foil side on one side and a soldering side on the opposite side. The smart card chip 2 is mounted on the soldering side of the single-interface strip. LA electrode grooves and LB electrode grooves are also provided on the soldering side of the single-interface strip, allowing electrical connection between the copper foil and the smart card chip. The smart card chip is electrically connected to the conductive areas inside the LA and LB electrode grooves via gold wires.

[0036] The single-interface strip can use either an 8-pin (8-contact module) or a 6-pin (6-contact module; the traditional 6-pin size still has 8 contacts, 6 of which are used normally, and the other 2 are used for LA and LB connections to the antenna. For example, with an 8-pin strip, there are 8 contacts (C1-C8) on the copper foil side, and these 8 contacts are electrically isolated from each other by insulating tape. Alternatively, with a 6-pin strip, there are 6 contacts (C1-C3, C5-C7) on the copper foil side, and these 6 contacts are electrically isolated from each other by insulating tape.

[0037] like Figure 2 As shown, a 6-pin single-interface strip 100 has six contacts, C1-C3 and C5-C7. The LA electrode recess 13A and LB electrode recess 13B are arranged symmetrically vertically. The LA electrode recess 13A is located between C1 and C5 and is independent of the C1 and C5 areas. The LB electrode recess 13B is located between C3 and C7 and is independent of the C3 and C7 areas. Both the LA electrode recess 13A and LB electrode recess 13B are connectors on the Inlay antenna 1 side of the card body.

[0038] Smart cards also feature encapsulation. In smart card packaging, encapsulation covers and cures the gold wires and the C1, C2, C3, C5, C6, and C7 contact pads (see [link to encapsulation instructions]). Figure 2 In the middle, the encapsulating glue range 16), while the remaining LA conductive protrusion 14A and LB conductive protrusion 14B are exposed and not covered by the encapsulating glue.

[0039] like Figure 3The diagram shows the back structure of an 8-pin single-interface strip 200, illustrating the structure of a standard 8-contact single-interface smart card chip module. This structure includes: smart card chip 2, gold wire leads, C1-C8 metal contacts, LA electrode recess, LB electrode recess, and encapsulation area. The small square in the center represents smart card chip 2, which integrates radio frequency (RF) circuitry and features two RF pins: chip LA pad 10A and chip LB pad 10B, used to sense RF signals from the inlay antenna. One set of gold wire leads connects the chip LA pad to the conductive area on the back of the C4 contact, and the other set connects the chip LB pad to the conductive area on the back of the C8 contact, connecting the internal RF pins of the chip to the conductive areas of the LA electrode recess 13A and LB electrode recess 13B on the back of the module (C4 and C8), thus establishing a circuit path between the chip and the external antenna.

[0040] like Figure 3 The encapsulation uses epoxy resin encapsulation. The 8-pin single-interface strip encapsulation range 26 covers the smart card chip 2 and all the gold wires, providing insulation, moisture protection, and buffer protection. However, the C4 and C8 positions are not completely sealed off, leaving through-hole recessed cavities, namely the LA electrode groove and LB electrode groove, to fill the recessed areas of conductive material.

[0041] Among them, the LA electrode groove and LB electrode groove of the single interface strip are distributed vertically.

[0042] Step S2: Fill and cure the LA electrode groove and LB electrode groove of the single-interface strip with conductive material.

[0043] Step S2 includes: Step S210: Fill the LA electrode groove and LB electrode groove of the single interface strip with conductive material.

[0044] The conductive material is precisely filled into the LA electrode groove and LB electrode groove area of ​​the single-interface strip using a dispensing machine. After filling, the conductive material protrudes 30-50um above the surface of the single-interface strip.

[0045] As an optional embodiment, the conductive material can be solder paste. The thickness of the conductive material filling is set according to the requirements of the conductive packaging process, with a reasonable solder thickness of 30-50µm above the strip surface. Insufficient thickness can easily lead to poor contactless function conduction, while excessive thickness will cause card surface protrusion and imprinting, affecting appearance and assembly quality.

[0046] Step S220: After filling with conductive material, the conductive material is cured to form conductive protrusions.

[0047] The conductive material is cured in an oven to form conductive protrusions.

[0048] Step S3: The surfaces of the conductive protrusions formed after curing in the LA electrode groove and LB electrode groove are flattened to form a flat and raised conductive contact surface.

[0049] Step S3 includes: In step S310, the LA conductive protrusions and LB conductive protrusions after being aligned and cured are milled using a CNC milling cutter to remove excess conductive material that protrudes beyond a predetermined range from the surface of the single interface strip.

[0050] The cured conductive material is milled flat using card-making equipment to a height of 20-30µm above the surface of the single-interface strip, retaining a uniform conductive protrusion 20-30µm above the strip surface to ensure contact flatness. During this process, the contact area of ​​the LA and LB electrode grooves and the winding density of the encrypted card body inlay antenna are maximized, improving contact reliability from both structural and technological perspectives and preventing card failure under torsion or bending conditions.

[0051] The surface of the conductive material formed after curing in the LA electrode groove and LB electrode groove is smoothed to eliminate the contact risk caused by structural unevenness.

[0052] Step S320: Remove conductive powder debris generated during milling.

[0053] Step S330: Detect the continuity resistance of the conductive bump.

[0054] Specifically, measure the conductive bumps LA and LB and the RF pins of the smart card chip 2 to eliminate products with open circuits or poor connections.

[0055] Step S4: Mill the enameled layer on the copper wire surface at the positions corresponding to the LA conductive protrusion and LB conductive protrusion on the inlay antenna of the card body to form the antenna LA conductive welding surface and the antenna LB conductive welding surface.

[0056] The conductive welding surfaces 15A (LA) and 15B of the antenna are formed by milling away the enameled coating on the copper wires of the inlay antenna. Specifically, the inlay antenna is milled to remove one-third of the enameled coating from the copper wires without compromising their conductivity. This ensures consistent flatness of the milled surfaces and prevents poor contact of conductive particles due to flatness deviations, which could affect contactless communication performance. The conductive welding surfaces LA and LB of the antenna are made of enameled copper wires arranged in a serpentine pattern. The milling process only removes the outer insulating enamel layer, exposing the internal conductive copper core; its purpose is to provide a clean conductive metal surface on one side of the antenna.

[0057] Step S4 includes: Step S410: Fix the inlay antenna on the card body.

[0058] In step S420, a CNC milling cutter is used to mill grooves in the copper wires at the positions corresponding to the conductive protrusions LA and LB.

[0059] Step S430: Mill the enameled layer of the copper wire area according to the set milling depth parameters of the CNC milling cutter.

[0060] The milling depth parameter removes only 1 / 3 of the thickness of the outer insulating enamel layer of the copper wire, while the copper core conductor is completely preserved without cutting the copper wire.

[0061] Step S440: Remove the debris generated during milling.

[0062] Step S450: Conduct conductivity continuity test on the inlay antenna of the card body.

[0063] Specifically, use a multimeter to measure the inductance and DC resistance at both ends of the conductive soldering surfaces LA and LB of the Inlay antenna, and discard defective Inlay antennas with milled copper wires, open coils, or incomplete removal of enamel.

[0064] Step S5: The processed single-interface strip is heat-pressed to the card body Inlay antenna using ACF conductive adhesive film.

[0065] Step S5 includes: Step S510: Pre-apply ACF conductive film to the LA conductive protrusion and LB conductive protrusion positions on the side of the single interface strip connected to the card body Inlay antenna.

[0066] Step S520: With the side pre-attached with ACF conductive adhesive film facing the card body Inlay antenna, align the positions of the LA conductive protrusion and LB conductive protrusion of the single interface strip with the antenna LA conductive soldering surface and antenna LB conductive soldering surface of the card body Inlay antenna.

[0067] In step S530, after alignment, a hot-pressing device is used to vertically press the single-interface strip and the card body Inlay antenna using predetermined hot-pressing parameters.

[0068] Step S540: Detect the conductive path between the card body Inlay antenna and the card body Inlay antenna.

[0069] Specifically, ACF conductive adhesive film is used to achieve a stable electrical connection between the conductive protrusions formed after curing in the LA and LB electrode grooves of the strip and the inlay antenna of the card body, balancing process simplicity and reliability.

[0070] ACF conductive adhesive film offers a simple, low-temperature connection method suitable for large-area mass production, avoiding the stringent control of welding processes and potential heat damage.

[0071] The temperature, time, and pressure packaging parameters may vary depending on the equipment model. The reference temperature is 190-220℃, the hot pressing time is 0.8-1.2s, and the hot pressing pressure is 2.4-2.6bar to ensure that the card's resistance to torsion and bending and the sealing strength meet industry standards.

[0072] like Figure 2-9 As shown, the second embodiment of this application provides a dual-interface smart card using a single-interface stripe, including a card base and a single-interface stripe, a smart card chip 2, and a card body inlay antenna 1 integrated inside the card base. The surface of the card base is provided with milled grooves, and the single-interface stripe and the smart card chip 2 are embedded in the milled grooves. One side of the single-interface stripe is a copper foil surface, and the opposite side is a welding surface. The smart card chip 2 is mounted on the welding surface of the single-interface stripe.

[0073] The single-interface strip 100 has 6 pins. At its center is a central area with six contacts (C1-C3, C5-C7) on the copper foil surface, surrounding the central area. Contact pads 11 are located at the positions of contacts C1, C2, C3, C5, C6, and C7. The smart card chip 2 has chip LA pads 20A and LB pads 20B, as well as chip contact pads electrically connected to the contact pads 11 corresponding to the C1, C2, C3, C5, and C7 contacts. The pads on the single-interface strip and the smart card chip 2 conform to the ISO 7816 standard.

[0074] In this application, as Figure 2 As shown, there is an independent metal contact between contacts C1 and C5, and another independent metal contact between C3 and C7. These independent metal contacts are electrically isolated from the other contacts by insulation, and are located in the central area. LA contact pad 12A and LB contact pad 12B are provided in the area where the two independent metal contacts are located on the soldering surface. LA contact pad 12A and LB contact pad 12B are electrically connected to the chip LA pad 20A and the chip LB pad 20B. In this application, the LA contact pad 12A and LB contact pad 12B are on the same axis and are symmetrically arranged vertically.

[0075] like Figure 4 As shown, LA electrode groove 13A and LB electrode groove 13B are also provided on the welding surface of the single interface strip. LA electrode groove 13A and LB electrode groove 13B are on the same axis and are arranged symmetrically above and below. LA electrode groove 13A is located between contacts C1 and C5 and is independent of the area where contacts C1 and C5 are located. LB electrode groove 13B is located between contacts C3 and C7 and is independent of the area where contacts C3 and C7 are located.

[0076] like Figure 5As shown, conductive material is filled into the LA electrode groove 13A and LB electrode groove 13B. After filling with conductive material, the conductive material is cured, and LA conductive protrusion 14A and LB conductive protrusion 14B are formed at the LA electrode groove 13A and LB electrode groove 13B. The surfaces of the LA conductive protrusion 14A and LB conductive protrusion 14B are flat and protrude from the surface of the single interface strip.

[0077] like Figure 7-8 As shown, the card body inlay antenna 1 is mounted on the card base. The card body inlay antenna is a loop coil. The card body inlay antenna has an antenna LA conductive soldering surface 15A and an antenna LB conductive soldering surface 15B. The antenna LA conductive soldering surface 15A and the antenna LB conductive soldering surface 15B are formed by milling off the enameled layer on the copper wire surface of the card body inlay antenna. The antenna LA conductive soldering surface 15A and the antenna LB conductive soldering surface 15B are respectively connected to the two ends of the card body inlay antenna. The antenna LA conductive soldering surface 15A and the antenna LB conductive soldering surface 15B are aligned with the LA conductive protrusion 14A and the LB conductive protrusion 14B.

[0078] The conductive welding surface 15A of antenna LA and the conductive welding surface 15B of antenna LB are formed by milling off the enameled layer on the surface of the copper wire on the inlay antenna of the body card. Specifically, 1 / 3 of the enameled layer outside the copper wire is milled off without damaging the conductivity of the copper wire, ensuring the overall flatness of the milled groove surface is consistent, and preventing poor contact of conductive particles due to flatness deviation, which would affect the non-contact communication performance.

[0079] The antenna LA conductive soldering surface 15A and antenna LB conductive soldering surface 15B of this application are made of enameled copper wire. The copper wire is arranged in a serpentine pattern. The milling groove only removes the outer layer of insulating enamel, exposing the internal conductive copper core, which is used to expose a clean conductive metal surface on the inlay antenna side of the card body. The antenna conductive soldering surface formed by the above design avoids the need to install the antenna LA pad and antenna LB pad on the inlay antenna of the card body in the traditional process.

[0080] like Figures 4-6 As shown, an encapsulating adhesive is also provided in this application. The encapsulating adhesive fills the encapsulating adhesive range 16. In the smart card packaging, the encapsulating adhesive covers and cures the gold wires and the C1, C2, C3, C5, C6, and C7 contact pads. The LA conductive protrusion 14A and LB conductive protrusion 14B are exposed and not covered by the encapsulating adhesive.

[0081] like Figures 6-9 As shown, in one embodiment of this application, the center of the ACF conductive adhesive film 3 is a hollow area, which corresponds to the position of the encapsulating adhesive of the single interface strip. In other words, the ACF conductive adhesive film can be applied to the area other than the encapsulating adhesive. The ACF conductive adhesive film 6 is an ACF anisotropic conductive adhesive film.

[0082] During packaging, Figure 6 The single-interface strip module with an ACF anisotropic conductive film attached is placed in Figure 7 On the card body inlay antenna shown, the single-interface strip module has one side of the ACF anisotropic conductive film facing the card body inlay antenna.

[0083] The single-interface strip and the card body inlay antenna are connected by a thermoforming method using ACF conductive adhesive film. The specific operation is as follows: the conductive protrusions of the single-interface strip are vertically aligned with the exposed antenna LA conductive welding surface and antenna LB conductive welding surface of the card body inlay antenna. Using a thermoforming device and with predetermined thermoforming parameters, the single-interface strip and the card body inlay antenna are vertically pressed together. The ACF film is then thermoformed and cured by a back adhesive positioning plate with a hollow area, forming electrical conductivity only in the vertical direction. That is, the antenna LA conductive welding surface 15A and the antenna LB conductive welding surface 15B are electrically connected to the LA conductive protrusion 14A and the LB conductive protrusion 14B, respectively, thus completing the permanent mechanical bonding between the two.

[0084] like Figure 3 As shown, the third embodiment of this application also provides a dual-interface smart card using a single-interface strip. The difference from the first embodiment is that the single-interface strip is 8 pins, with a total of 8 contacts C1-C8, whose positions and dimensions conform to the ISO7816 standard. In this application, C4 extends outwards to the outer regions of C3, C2, and C1; C8 extends outwards to the outer regions of C7, C6, and C5, forming two extension areas. An 8-pin single-interface strip LA electrode groove 23A and an 8-pin single-interface strip LB electrode groove 23B are each provided on the substrate where the extension areas of C4 and C8 are located. In this application, the 8-pin single-interface strip LA electrode groove 23A and the 8-pin single-interface strip LB electrode groove 23B are symmetrically arranged vertically.

[0085] In this embodiment, the 8-pin single-interface strip LA electrode groove 23A and the 8-pin single-interface strip LB electrode groove 23B are also treated in the same way to form LA conductive protrusions and LB conductive protrusions.

[0086] In this embodiment, the contact pads of C4 are electrically connected to the chip LA pad 20A via gold wire bonding 27, and the contact pads of another set of C8 are electrically connected to the chip LB pad 20B via gold wire bonding 27.

[0087] In the encapsulation process, the soldering surface of the single-interface strip is covered with encapsulating adhesive to cover the chip, and the gold wires and C1, C2, C3, C5, C6, C7 and C4, C8 contact pads are covered with encapsulating adhesive and cured. The remaining parts, including the LA conductive bump and LB conductive bump, are exposed. The module is now encapsulated and then undergoes a testing process.

[0088] The card body inlay antenna is provided with an antenna LA conductive welding surface and an antenna LB conductive welding surface. The formation process of the antenna LA conductive welding surface and the antenna LB conductive welding surface is exactly the same as that in the first embodiment, and will not be described again here.

[0089] Similar to the scheme in the first embodiment, the positions of the LA conductive protrusions and LB conductive protrusions also correspond to the positions of the antenna LA conductive welding surface and the antenna LB conductive welding surface. An ACF conductive adhesive film 3 is pre-attached to the LA conductive protrusions and LB conductive protrusions on the side of the single-interface strip connected to the card body Inlay antenna. Using a hot-pressing device and predetermined hot-pressing parameters, the single-interface strip and the card body Inlay antenna are vertically pressed together, electrically connecting the antenna LA conductive welding surface and the antenna LB conductive welding surface to the LA conductive protrusions and LB conductive protrusions, respectively.

[0090] The beneficial effects achieved by this application are as follows: (1) In this application, the LA electrode groove and LB electrode groove of the single interface strip are filled with conductive material and milled flat to form a flat raised conductive contact surface, thereby eliminating the uneven force caused by the LA electrode groove and LB electrode groove.

[0091] (2) In this application, the LA electrode groove and LB electrode groove of the single interface strip are changed to be arranged vertically from top to bottom, which is aligned and matched with the antenna pad of the card body, reducing the risk of assembly misalignment.

[0092] (3) In this application, the copper wire enameling layer is removed from the antenna LA conductive welding surface and the antenna LB conductive welding surface of the inlay antenna of the card body, exposing the copper core and eliminating insulation barrier.

[0093] (4) This application uses ACF anisotropic conductive adhesive film to heat-press bond the single interface strip and the card body Inlay antenna. The single interface strip and the card body Inlay antenna are connected with flat conductive surfaces on the top and bottom, ensuring stable vertical conduction, greatly reducing open circuits and poor connections, and improving the card production qualification rate.

[0094] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0095] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for manufacturing a dual-interface smart card based on a single-interface stripe, characterized in that, The method includes: The LA electrode groove and LB electrode groove of the single-interface strip are filled with conductive material and then cured. The conductive material surfaces formed after curing in the LA electrode groove and LB electrode groove are flattened to form LA conductive protrusions and LB conductive protrusions. The surfaces of the LA conductive protrusions and LB conductive protrusions are flat and protrude from the surface of the single interface strip. The enameled layer on the copper wire surface at the positions corresponding to the LA conductive protrusion and LB conductive protrusion on the inlay antenna of the card body is milled off to form the LA conductive welding surface and the LB conductive welding surface of the antenna. The processed single-interface stripe is heat-pressed to the inlay antenna of the card body using ACF conductive adhesive film.

2. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The process of filling and curing the LA electrode groove and LB electrode groove of the single-interface strip with a conductive material includes: filling the LA electrode groove and LB electrode groove of the single-interface strip with a conductive material; After filling with conductive material, the conductive material is cured to form LA conductive protrusions and LB conductive protrusions respectively.

3. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The surfaces of the conductive materials formed after curing in the LA and LB electrode grooves are smoothed to form LA conductive protrusions and LB conductive protrusions, including: The LA and LB conductive protrusions after being aligned and cured are milled using a CNC milling cutter to remove excess conductive material that exceeds the predetermined range above the surface of the single interface strip. Remove conductive powder debris generated during milling; Conduct resistance testing is performed on the conductive protrusions.

4. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, Milling removes the enameled layer from the copper wire surfaces at positions corresponding to the LA and LB conductive protrusions on the inlay antenna of the card body, forming the antenna LA conductive solder surface and the antenna LB conductive solder surface, including: Fix the inlay antenna on the card body; A CNC milling cutter is used to mill grooves in the copper wires at the positions corresponding to the LA conductive protrusion and LB conductive protrusion. Based on the set milling depth parameters of the CNC milling cutter, the enameled layer in the copper wire area is removed by milling.

5. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The processed single-interface stripe is heat-pressed to the inlay antenna of the card body using ACF conductive adhesive film, including: Align the LA conductive protrusion and LB conductive protrusion with the antenna LA conductive welding surface and antenna LB conductive welding surface of the inlay antenna of the card body; After alignment, a hot-pressing device is used to vertically press the single-interface strip and the card body inlay antenna using predetermined hot-pressing parameters.

6. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The single-interface strip is provided with symmetrical LA electrode grooves and LB electrode grooves.

7. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The conductive material filling the LA electrode groove and LB electrode groove extends 30-50 μm above the surface of the single-interface strip.

8. The method for manufacturing a dual-interface smart card based on a single-interface stripe according to claim 1, characterized in that, The cured conductive material in the LA electrode groove and LB electrode groove is milled flat to 20-30 μm above the surface of the single interface strip.

9. A dual-interface smart card employing a single-interface stripe, characterized in that, The card is manufactured according to the method of any one of claims 1-8, including a card base and a single-interface strip, a smart card chip and a card body inlay antenna integrated inside the card base. The surface of the card base is provided with a milled groove, and the single-interface strip and the smart card chip are embedded in the milled groove. One side of the single-interface strip is a copper foil side and the opposite side is a welding side, and the smart card chip is mounted on the welding side. The single-interface strip has a central area at its center. There are six contacts on the copper foil surface, C1-C3 and C5-C7, which surround the central area. Contact pads are provided at the positions of contacts C1, C2, C3, C5, C6, and C7. The smart card chip is provided with chip LA pads, chip LB pads, and chip contact pads that are electrically connected to the contact pads of contacts C1, C2, C3, C5, and C7. The chip LA pads and chip LB pads are electrically connected to the LA contact surface pads and LB contact surface pads located in the central area. The welding surface of the single-interface strip is also provided with LA electrode groove and LB electrode groove. The LA electrode groove and LB electrode groove are on the same axis and are arranged symmetrically above and below. The LA electrode groove is located between contacts C1 and C5 and is independent of the area where contacts C1 and C5 are located. The LB electrode groove is located between contacts C3 and C7 and is independent of the area where contacts C3 and C7 are located. The LA electrode groove and LB electrode groove are filled with conductive material. After filling with conductive material, the conductive material is cured to form LA conductive protrusion and LB conductive protrusion at the LA electrode groove and LB electrode groove. The LA conductive protrusion and LB conductive protrusion have flat surfaces and protrude from the surface of the single interface strip. The card body Inlay antenna is provided with an antenna LA conductive welding surface and an antenna LB conductive welding surface. The antenna LA conductive welding surface and the antenna LB conductive welding surface are formed by milling off the enameled layer on the copper wire surface of the card body Inlay antenna. The antenna LA conductive welding surface and the antenna LB conductive welding surface are respectively provided with LA conductive protrusion and LB conductive protrusion. The LA conductive protrusion and LB conductive protrusion are pre-attached with ACF conductive adhesive film. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body inlay antenna are vertically pressed together to electrically connect the antenna LA conductive welding surface 15A and antenna LB conductive welding surface 15B to the corresponding LA conductive protrusion and LB conductive protrusion.

10. A dual-interface smart card employing a single-interface stripe, characterized in that, The card is manufactured according to the method of any one of claims 1-8, including a card base and a single-interface strip, a smart card chip and a card body inlay antenna integrated inside the card base. The surface of the card base is provided with a milled groove, and the single-interface strip and the smart card chip are embedded in the milled groove. One side of the single-interface strip is a copper foil side and the opposite side is a welding side, and the smart card chip is mounted on the welding side. The single-interface strip has 8 pins and 8 contacts from C1 to C8. C4 extends outward to the outer regions of C3, C2, and C1; C8 extends outward to the outer regions of C7, C6, and C5, forming two extension areas. An LA electrode groove and an LB electrode groove are respectively provided on the substrate of the extension areas of C4 and C8. The LA electrode groove and the LB electrode groove are symmetrically arranged on the top and bottom. The LA electrode groove and LB electrode groove are filled with conductive material. After filling with conductive material, the conductive material is cured to form LA conductive protrusion and LB conductive protrusion at the LA electrode groove and LB electrode groove. The LA conductive protrusion and LB conductive protrusion have flat surfaces and protrude from the surface of the single interface strip. The LA conductive protrusion and LB conductive protrusion correspond to the positions of the antenna LA conductive welding surface and the antenna LB conductive welding surface. ACF conductive adhesive film is pre-applied to the LA conductive protrusion and LB conductive protrusion positions on the side of the single interface strip connected to the card body Inlay antenna. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body Inlay antenna are vertically pressed together, and the antenna LA conductive welding surface and antenna LB conductive welding surface are electrically connected to the LA conductive protrusion and LB conductive protrusion respectively. The LA conductive protrusion and LB conductive protrusion correspond to the positions of the antenna LA conductive welding surface and the antenna LB conductive welding surface. ACF conductive adhesive film is pre-applied to the LA conductive protrusion and LB conductive protrusion positions on the side of the single interface strip connected to the card body Inlay antenna. Using a hot pressing device and with predetermined hot pressing parameters, the single interface strip and the card body Inlay antenna are vertically pressed together, and the antenna LA conductive welding surface and antenna LB conductive welding surface are electrically connected to the LA conductive protrusion and LB conductive protrusion respectively.

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