FR3030087A1 - MODULE FOR MICROCIRCUIT CARDS, MICROCIRCUIT CARDS COMPRISING SUCH A MODULE AND METHOD OF MANUFACTURE - Google Patents

Abstract

The invention relates to a module (12) for a microcircuit card (10) comprising an antenna (18), the module (12) comprising a substrate delimited by an external face, covered by metal contact surfaces, and a internal face of the module (12) having a covering area (24) intended to be superposed on the ends of the antenna (18), a microcircuit (14) mounted on the inner face and electrically connected to the contact surfaces, the module ( 12) further comprising at least one connection element electrically connected on the one hand to the microcircuit (14). The connection element comprises a first part fixed on the internal face of the module (12) and a second part movable between an initial position in which it extends beyond the covering area (24) and a position of use in which it is adapted to be kept immobile substantially vis-à-vis the area of recovery (24).

Description

Module for microcircuit cards, microcircuit cards comprising such a module and manufacturing method. The present invention relates to modules for microcircuit cards comprising an antenna, such as payment cards, transport cards or any other type of card intended to communicate with a terminal. It relates more particularly to so-called dual card modules capable of exchanging data with a terminal either by direct contact or remotely by means of an antenna. The module comprises a substrate defined by an outer face, covered by metal contact surfaces intended to come into contact with the terminals of the terminal, and an inner face having a covering area intended to be superimposed on the ends of the antenna. The module further comprises a microcircuit mounted on the inner face and electrically connected to the contact surfaces. In addition at least one connecting element disposed on the inner face is electrically connected to the microcircuit.

The microcircuit capable of exchanging data with the terminal is generally disposed on the internal face of the module. It is therefore easy to connect it to the metal surfaces made on the outer face of said module through wires through wells passing through the thickness of the module substrate. On the other hand, it is more difficult to connect the microcircuit to the antenna which is generally inserted in a central plastic layer of the card body.

Various solutions have been developed to address the connection problem between the module and the antenna located in the card body. It is for example known to make a cavity at the bottom of which the ends of the antenna are accessible. The module comprises a contact pad connected to the microcircuit and intended to come substantially opposite the ends when the module is mounted in the cavity. A connection means is disposed between the contact area and the end of the antenna to provide the electrical connection between the two components.

This connection means may be a conductive wire, a conductive alloy bump or an anisotropic adhesive. However, each of the abovementioned technologies has disadvantages. For example the connection by conducting wire is relatively fragile and therefore a high risk of cutting or tearing of the wire thus preventing the use of the card with a remote terminal. A recent alternative solution proposes to make an antenna directly on the module and to couple it with the antenna integrated in the card body, the parameters of the two antennas being chosen to operate at a frequency determined by the terminal. However, this solution has a relatively high cost and requires modifying the structure of the module.

The present invention provides a novel alternative to the prior art solutions, by addressing the aforementioned drawbacks. For this purpose, the present invention proposes a module of the type described above, wherein the connection element comprises a first part fixed on the internal face of the module and a second part movable between an initial position in which it extends beyond beyond the overlap zone and a use position in which it is adapted to be kept substantially facing the overlap zone. Thanks to these arrangements, the module has a new simple connection means, low cost and can be mounted on the inner face of the module during manufacture thereof. In addition, these arrangements facilitate the subsequent step of mounting the module in the card body by removing a step of removing a connection means such as a wire or a metal bump. According to other features: - the second part is movable between the initial position and the position of use by folding; the module further comprises an adhesive deposited on the periphery of the inner face of the substrate and covering the first part; the connection element is formed by a metal plate substantially of the same thickness as the substrate; The connecting element is formed by a metal ribbon of a thickness substantially equal to that of the substrate; - The module comprises a contact pad and connected to the microcircuit and in that the first part is fixed on said contact pad; The first part of the connection element is electrically connected to the microcircuit by conducting wires; The invention also relates to a microcircuit card comprising a body provided with an antenna and an opening cavity formed in the body, the ends of the antenna being accessible from said cavity. The card further comprises a module as described above, the second part being in the use position and in contact with the ends of the antenna. According to other features: - the connection element is constrained in the cavity so that the second part exerts a restoring force towards the ends of the antenna. The invention also relates to a method of manufacturing a module according to the invention comprising the following steps: Provision of a longitudinal strip of substrates comprising, over its width, at least one module having an outer surface covered with surfaces of metal contact and an inner face comprising a microcircuit and at least two contact pads intended to be electrically connected to the antenna and arranged on either side of the microcircuit in the width direction, removing a strip forming the metal connecting element in a direction perpendicular to the longitudinal direction so as to cover the two contact pads, deposits a non-conductive adhesive on the periphery of the inner face of the module, cutting the strip substantially in the middle of the two contact pads, folding the connection element so that the second part is folded to the right of the dedicated pad to the antenna. According to other characteristics of the process: the second part extends between the first part and the midpoint; the second portion extends between the first portion (36) and the end of the strip (42) extending beyond the substrate.

The present invention will be better understood on reading the following description given with reference to the appended figures in which: FIG. 1 represents an exploded perspective view of a dual map; FIG. 2 represents the internal face of a module according to the prior art; FIG. 3 represents the internal face of a module according to the invention, the connection element of which is in the initial position; FIGS. 4a and 4b respectively show a view of the internal face and a side view of a module according to the invention, the connection element of which is in the position of use; FIG. 5 represents an alternative embodiment of a connection element in the position of use; FIG. 6 schematically represents a step of a method of manufacturing a strip of modules according to the invention. FIG. 1 illustrates a microcircuit card 14 and comprising a module 12 according to the invention.

The card 10 is dual, i.e., capable of communicating with an external terminal through a physical connection and a remote connection. For this purpose, the module 12 comprises a microcircuit 14 electrically connected to two communication interfaces. A first interface consists of metal surfaces 16 disposed on the module 12 and intended to come into physical contact with the pins of a terminal. The other interface consists of an antenna 18 set to the communication frequency of the terminal. The card 10 comprises a plastic body of ID-1 format which designates a generally rectangular shape of 54mm * 85.6mm * 0.8mm according to ISO / IEC 7816. This body can be obtained directly by molding or by assembly of plastic layers by heating and pressure. The body has a relatively thin thickness with respect to the dimensions of the external faces of the card 10. A countersink opening on one of the faces of the card 10 is adapted to receive the module 12. For this purpose the countersink comprises a lower cavity 20 lined by a step 22 forming itself an upper cavity. The module 12 is inserted into the countersink and bears against the step 22.

The antenna 18 has at its ends conducting elements 23 arranged to open onto the step 22. These conducting elements 23 are constituted, for example, by a conductive metal plate as shown in FIG. 1. The conductive elements 23 are made accessible by the machining step performing the counterbore. The module 12 is mounted in the cavity and has a theoretical zone, called the overlap area 24, arranged facing each of the conductive elements 23 of the antenna 18. The covering zone 24 has substantially the same peripheral dimensions as those of the machined part of the conductive elements 23 so as to cover them. A connection element 26 between the microcircuit 14 and the antenna 18 is disposed on the covering zone 24.

The module 12 is mounted flush with one face of the card body 10. It has, as can be seen in FIG. 2, a substrate 28, for example made of epoxy glass or PET, having an internal face 30 on which the microcircuit is mounted. 14 and an outer face, visible in Figure 1, on which are engraved the metal surfaces 16. These metal surfaces 16 are intended to come into contact with the pins of the reader in which the card 10 is inserted.

As can be seen in FIG. 2, the module 12 has on its internal face 30 a plurality of contact pads for connecting the microcircuit 14 to the various communications interfaces with the terminals. For this purpose the microcircuit 14 is electrically connected to the contact pads by cables, such as son 40 gold. Two contact pads 34 are intended to connect the microcircuit 14 to the antenna 18 disposed in the card body 10. These two contact pads 34 advantageously overlap the theoretical overlap zone 24 so as to cover it at least partially. This overlap zone 24 is shown only in FIGS. 1 and 2, for a better reading of the drawings. As can be seen in FIG. 3, an electrical connection element 26 is arranged in the overlap zone, that is to say between a contact pad 34 and a conductive element 23 at the end 25 of the antenna 18. The connection element makes it possible to form a conductive path between the antenna 18 and the microcircuit 14. The connection means 26 according to the invention is illustrated in FIGS. 3, 4a and 4b and comprises a first portion 36 fixed on the face internal 30 and electrically connected to the microcircuit 14 and a second part 38.

According to a first embodiment, the first portion 36 is fixedly mounted on the connection pad and the second portion 38 is movable between an initial position in which it extends beyond the overlap zone 24 and a position in which it is adapted to be kept stationary substantially opposite said overlap area 24.

The expression "kept still" means that the second portion 38 remains in the same position and is secured to the substrate 28 when the module 12 is moved. According to a second variant of the invention, the internal face 30 of the module 12 does not have a contact pad 34 dedicated to the antenna 18, and the first part 36 is directly fixed on the internal face 30 of the module 12 and electrically connected. on the chip by wires 40 conductors. The second portion 38 is also movable between an initial position in which it extends beyond the overlap zone 24 and a use position in which it is adapted to be kept stationary substantially at least vis-à-vis The second portion 38 is preferably brought into the use position by folding to be superimposed and at least partially cover the overlap zone 24 to ensure a good electrical connection. The connecting element 26 is formed by a metal thin plate having a thin thickness of between 10 and 70 μm and adapted to be folded down. It can be made of copper or metal alloy. It is substantially flat. It is fixed by welding on the internal stud 34 to ensure the continuity of the electrical connection. Adhesive spots on the inner face 30 of the module 12 can improve the fixation of the first part 36 of the connection element 26. In the absence of contact stud 34, the plate is directly fixed by bonding on the face internal circuit 30 of the module 12. Advantageously the plate has two arms which extend in the direction of the microcircuit 14 and on which are fixed by welding gold wires 40 connected on the other hand to the microcircuit 14.

The second part 38 integral with the first part 36 is not directly fixed on the internal face 30 of the module 12. It is attached indirectly to the module 12 via the first part 36. As can be seen in FIG. extends beyond the module 12 to the initial position 6 3030087. According to an alternative embodiment, it extends towards the microcircuit 14, above it. Advantageously, the second portion 38 is held stationary vis-à-vis the contact pad 34 dedicated to the antenna 18 after being folded down by folding. For this purpose the connection element 26 5 has one or more partially thinned edges defining a folding zone of the second part 38 in the direction of the first part 36. The folding zone can present in profile a shape in V or a U-shape as shown in Figure 5. These profiles 40 provide a spring function when the connecting member 26 is compressed after mounting the module 12 in the cavity. Indeed, the connection element 26 is subjected to a compressive force in a direction perpendicular to the plane of the module 12 when it is mounted in the cavity. The U-profile will be preferred for the implementation of the invention, since it makes it possible to extend the second portion 38 in a plane substantially parallel to the first portion 36, and thus parallel to the step 22 where the ends of the the antenna 18. These arrangements ensure a greater contact area between the end of the antenna 18 disposed on the step 22 and the connecting element 26. As shown in Figure 5a, projections 54 formed on the second part 38 in the direction opposite to the first part 36 improve the contact between the ends of the antenna 18 and the connecting element 26. The connecting element 26 has the advantage of being reliable and robust to withstand various manipulations of the card 10. It must be as easily reproducible to be produced on a large scale and easily implemented during the manufacture of modules and cards. The module 12 according to the present invention can be made according to several methods. In general, the modules 12 are made from a strip 42 of substrate 28 unwound and on which will be performed several operations to obtain the desired module 12. These strips have standard widths so as to be able to contain two modules 12 over the width of the strip 42. The modules are obtained by a step of depositing and etching the metal to form a printed circuit with the metal surfaces 16 on. the outer face 32. It follows a step of fixing the microcircuit 14 on the inner face 30 and a step of electrically connecting the microcircuit 14 for example by son 40 gold. The chip and the gold wires are then embedded in a resin.

After these steps, it is then possible to fix the connection element 26 on the contact pad 34. According to a first method of manufacture, each metal element is deposited on the contact pad 34 and then fixed by ultrasonic welding, for example . The continuous strip arrangement 42 of the modules 12 makes it possible to deposit the connection elements successively and automatically.

According to a second embodiment, illustrated in FIG. 5, the connection elements are in the form of a metal strip 44 deposited on the internal face 30 of the module 12 in the width direction of the strip 42. ribbon 44 has a width of 1mm to 3mm and a thickness of 81..tm at 20 grn. The ribbon 44 is deposited over the entire width of the strip 42 and covers the contact pads 34s dedicated to the antenna 18 and the coating of the microcircuit 14. A hooking of the metal strip 42 may be favored by a hot spot (a pressing finger, blowing ...). A cutting step is then necessary to divide the ribbon 44 into two parts respectively connecting the two contact pads 34 of the same module 12 to avoid any risk of short circuit. A non-conductive adhesive 46 is then deposited on the periphery of the inner face 30 of the module 12. This adhesive 46 will allow the mechanical attachment of the module 12 to the step 22. The adhesive 46 covers the first parts of the connection elements. It is deposited according to the usual methods by hot pressing. Thus the first portion 36 is found between the substrate 28 of the module 12 and the adhesive mass. The folding step is then performed to fold the second portion 38 at least partially above the overlap area 24. The folded second portion 38 may extend initially beyond the inner face 30 or substantially above the resin coating of the microcircuit 14.

The insertion of the module 12 is then carried out according to the usual methods and the connection element 26 will make the electrical contact interface between the microcircuit 14 and the ends of the antenna 18. The present invention thus offers a new alternative. for the electrical connection between the module 12 and the antenna 18 in the card body 10 without modifying the embedding processes 5 used to date, and therefore does not require a modification of the existing tools park. In addition, this new solution makes it possible to dispense with an expensive conductive adhesive 46. 9

Claims (12)

CLAIMS1.Module (12) for a microcircuit card (10) comprising an antenna (18), the module (12) comprising: a substrate (28) delimited by an outer face (32), covered by metal contact, and an inner face (30) of the module (12) having a covering area (24) to be superimposed on the ends of the antenna (18), - a microcircuit (14) mounted on the inner face (30). ) and electrically connected to the contact surfaces, - the module (12) further comprising at least one connection element (26) electrically connected on the one hand to the microcircuit (14), characterized in that the connection element (26) ) has a first portion (36) fixed to the inner face (30) of the module (12) and a second portion (38) movable between an initial position in which it extends beyond the overlap area (24) and a use position in which it is adapted to be held immobile substantially opposite the covering area (24). 2. Module according to claim 1, wherein the second portion (38) is movable between the initial position and the use position by folding. 3. Module according to one of the preceding claims, further comprising an adhesive (46) deposited on the periphery of the inner face (30) of the substrate (28) and covering the first portion (36). 4. Module according to one of the preceding claims, wherein the connecting element (26) is formed by a metal plate substantially of the same thickness as the substrate (28). 5. Module according to one of claims 1 to 3, wherein the connecting element (26) is formed by a ribbon (44) of a metal thickness substantially equal to that of the substrate (28). 6. Module according to the preceding claim, comprising a contact pad (34) and connected to the microcircuit (14) and in that the first portion (36) is fixed on said contact pad (34). 10 3030087 7. Module according to one of claims 1 to 5, wherein the first portion (36) of the connecting member (26) is electrically connected to the microcircuit (14) by son (40) conductors. 8. A microcircuit card comprising a body provided with an antenna (18) and a through-hole formed in the body, the ends of the antenna (18) being accessible from said cavity, characterized in that it further comprises a module (12) according to one of claims 1 to 7, the second portion (38) being in use position and in contact with the ends of the antenna (18). The card of claim 8, wherein the connecting member (26) is constrained in the cavity such that the second portion (38) exerts a restoring force toward the ends of the antenna (18). 10. A method of manufacturing a module according to claims 7 and 5 comprising the following steps: - Provision of a strip (42) of longitudinal substrates (28) having, along its width, at least one module (12) having an outer face (32) covered with metal contact surfaces and an inner face (30) having a microcircuit (14) and at least two contact pads (34) to be electrically connected to the antenna (18) and arranged on either side of the microcircuit (14) in the width direction, - Removal of a strip (42) forming the metal connection element (26) in a direction perpendicular to the longitudinal direction so as to cover the two contact pads (34), 20 - depositing a non-conductive adhesive (46) around the inner face (30) of the module (12), - cutting the strip (42) substantially in the middle of the two contact pads (34), - folding of the connection element (26) so that the second me part (38) is folded to the right of the stud dedicated to the antenna (18). 11. A method of manufacturing a module (12) according to claim 10, wherein the second portion (38) extends between the first portion (36) and the midpoint. A method of manufacturing a module 12 according to claim 10, wherein the second portion (38) extends between the first portion (36) and the end of the strip (42) extending beyond the substrate (28). 11