HK1261295B - Method for manufacturing a smart card module and a smart card - Google Patents

Description

The invention relates to the field of smart cards, which are well known to the public and have many uses: payment cards, SIM cards for mobile phones, transport cards, identity cards, etc.

The invention is particularly useful for the production of dual-interface chip cards. Such cards are described for example in documents2014/208532A1 and EP0671705A2. Dual-interface chip cards are called dual (or dual interface ) if the dual-contact and contactless modes are managed by a single chip or hybrid contactless and

Dual interface chip cards are usually made of a rigid plastic support such as PVC, PVC/ABS, PET or polycarbonate that makes up the core of the card, in which an electronic module and an antenna are built separately. The electronic module consists of a printed circuit board usually flexible with an electronic chip and contact bands electrically connected to chip connecting plots. The contact bands protrude on the electronic module, on the surface of the card support, for an electrical contact connection with a card reader device.

In earlier art, the electronic module comprising contacts and the chip on the one hand, and the antenna possibly integrated into a support ( inlay according to Anglo-Saxon terminology) on the other hand, are usually manufactured separately, and then the antenna is connected to the module.

One purpose of the invention is to simplify and make this type of process more reliable.

This is at least partially achieved by a manufacturing process of a chipboard module, according to claim 1.

The method of the invention therefore simplifies the method of the present invention compared with the methods of the previous art in which the second end of the wire is carried over a conductive track, either on the front face (also called face ) or on the back face (also called face bonding), and in which this conductive track must be connected, for example by welding and/or connecting another wire to the antenna, to the track itself.

This process of manufacturing a chipboard module may include any of the following characteristics considered independently of or in combination with one or more of the others: It consists of a step whereby the second end of the wire is fixed to a backing plot, through a connection well previously made through the substrate; this arrangement allows the second end of the wire to be held before it can be held in another way (for example by a layer of hot melt material as shown below); it consists of a step whereby a cut is made around a chip connected to the first end of a wire,This cut-off defines the final dimensions of the individual module and the connection shaft into which the second end of the wire is attached, after cutting it out of the module; thus, the connection shaft, which in this case corresponds to a temporary structure, no longer appears on the finished product; it consists of a step in which a hot-melt material is applied to the second side of the substrate, so that the wire is accessible on one side and maintained on another side between the substrate and the hot-melt material; for example, a window is made in the hot-melt material,leaving the wire accessible through the window; etil has a step a step in which the module is individualised by cutting it according to its final dimensions (i.e. the dimensions of the module when housed in a card),

In another respect, the invention relates to a process for manufacturing a smart card according to claim 7.

This process of manufacturing a chip card may have either of the following characteristics considered independently of or in combination with one or more others: The first end of the wire is encapsulated in an encapsulation resin; a portion of the wire is held, outside the encapsulation resin, at least partially on the substrate by means of a heat-fused material; a portion of a wire connected to the chip is welded to a connection range of the antenna by applying a thermode to a contact on the first face (face contact) of the substrate.

In another respect, the invention relates to a chipboard module according to claim 11.

The chipboard module may also include a layer of hot melt material applied to the second side of the substrate, leaving at least part of the wire exposed to the hot melt material.

In another respect, the invention relates to a chipboard according to claim 13, where the first end of the wire is encapsulated with the chip in a resin and the portion outside the encapsulation resin is welded, through an opening in a hot melt sheet, to a connection range of the antenna.

Further features and advantages of the invention will be apparent from the detailed description and the attached drawings on which: Figure 1 shows a schematically, in perspective, of a chipboard according to the invention;Figure 2 shows a schematically, in perspective and in a split-form of the chipboard in Figure 1;Figure 3 shows a schematically, from above and from the front, of a portion of a substrate strip for the manufacture of chipboard modules such as that in Figures 1 and 2;Figure 4 shows a schematically, in perspective and in a split-form of the substrate strip in Figure 3 as seen from the rear;Figure 5 shows a schematically, in perspective, of a chipboard module such as that in Figures 1 and 2.

As shown in Figure 1, a chipboard 1 has a module 2. The chipboard 1 consists of several layers 3, 4, 5 rolled on top of each other.

For example, the chipboard shown in Figure 2 has a lower finishing layer 3, an antenna support ( inlay ) 4 and an upper finishing layer 5.

The lower finish layers 3 and 5 may be, for example, printed PVC layers.

The antenna support 4 is itself generally known to be composed of several layers between which a wired antenna is embedded or engraved in a sheet of metal (in Figure 2, antenna 6 inserted between two layers is shown in dotted lines).

For example, antenna 6 has a conductive line wrapped in several loops extending around the periphery of the board 1. Each of the two ends of the line is connected to a connection range 7. The connection ranges 7 are at least partially visible and accessible at an opening 8 located in a top layer 9 of the antenna support 4.

In the process of manufacturing chipboard 1, the lower finishing layers 3, upper 5 and the antenna support 4 are rolled together, and then a cavity 11 is milled in the upper finishing layer 5 to accommodate a module 2 and to expose the connection bands 7 of the antenna 6, each equipped with a welding plot 10 respectively.

In addition, the manufacturing process of module 2 involves making 12 metal contacts on a flexible substrate 13 (see Figure 3). Substrate 13 has a first 14 and a second 15 main faces, with the 12 contacts on the first 14 side of substrate 13 (front or front contact).

These contacts are made, for example, by engraving a sheet of metal (e.g. copper alloy) on a dielectric substrate (e.g. epoxy glass) or by cutting metal patterns and transferring these patterns onto a dielectric substrate (so-called leadframe technology).

As shown in Figure 4, substrate 13 is perforated to make connection wells 16 whose bottom is blocked by the 12 contacts. Chips 17 (one per module) are glued to the back 15 of substrate 13 (face bonding). Each chip 17 is connected by conductive wires 18 connecting, through the 16 connection wells, contacts 12 to chip 17 connection plots.

In addition, two connecting plots of the chip are connected, also by 18 wires through 16 connecting wells, each to a 19 delay plot respectively. Each delay plot 19 is made in a similar manner to and simultaneously with the 12 contacts. The 18 connecting wires from the 17 chip to the 6 antenna are therefore each connected by a first end to the 17 chip and by a second end to a 19 delay plot.

A layer of hot melt material 20 in which the openings 21, 22 are removed is then applied to the back face 15 of the substrate 13. This layer of hot melt material 20 allows module 2 to be fixed in its cavity 11 milled into the board 1. The openings 21, 22 are of two types: large openings 21 in which the chips 17 and wires 18 from chip 17 come to contact 12, and smaller windows 22, through which a wire 18 from chip 17 to antenna 6 remains visible and accessible. Each of these windows 22 is traversed by a portion 23 of the wire 18 from chip 17 to antenna 7 (see FIG. 5). This portion 23 18 is maintained on two opposite sides of the substrate without any adherent material. Each portion of the wire 22 is relatively free to adhere to the surface of the substrate.

An encapsulation resin 25 covers chip 17 and the wires 18 connecting chip 17 to contacts 12. The encapsulation resin 25 drop is bounded by the edge of the large openings 21. The windows 22 through which a portion 23 of the wires 18 connecting chip 17 to antenna 6 passes are free of resin 25.

On the finished and individualised module 2, the layer of thermal-melt material 20 forms a frame all around the chip 17. Only two windows 23 are cut into this frame. The dimensions of these windows 23 are relatively small (e.g. 1mmx2mm). Thus, the presence of these windows 23 has virtually no influence on the adhesion of module 2 to edges 24 made when milling cavity 11 of board 1 (see FIG. 2).

After cutting the module 2 individually in its final dimensions, the 19 support shafts to which the second ends of the 18 wires connecting chip 17 to antenna 6 were connected were removed.

The module 2 is then carried back into a cavity 11 milled into a chip board 1.The windows 23 through which the 18 wires connecting the chip 17 to the antenna 6 pass are placed vis-à-vis the 7 wires connecting the antenna 6 left exposed in cavity 11.

A thermode (not shown) is applied to the contact face 14 of module 2. The heat supplied by the thermode reacts the thermosetting material 20 located on the back face 15 of module 2. The thermosetting material 20 adheres to edges 24 created in cavity 11 during its milling. Furthermore, the thermode melts the welding plots 10 placed on the connection ranges 7 of the antenna 6. The thermode is heated to a temperature between 120°C and 250°C. The conduction of heat between the thermode and the welding plot 10 is particularly efficient as it is done only through the contacts 12 which are good thermal conductors and the substrate 13.

The welded solder from solder plots 10 comes into contact with portion 23 of wire 18 through each window 22. The partly soldered portion 23 of wire 18 is then electrically connected to the antenna 6. Furthermore, the solder not adhering to substrate 13 or hot-melt material 20, portion 23 of wire 18 taken into the solder is solid to the connection plots 7 of antenna 6 but retains relative freedom of movement relative to module 2. This relative freedom of movement and elongation properties of wire 18 allow to compensate for the motions of module 2 relative to the rest of the board body 1, and to absorb the contra-connections generated between them when using the latter, and sometimes avoid the accidental antenna deviations observed in the previous board 6.

Claims (14)

1. Method for producing a chip card (1) module (2), in which:

   - a substrate (13) having a first (14) main face and a second (15) main face is provided, with contacts (12) on the first face (14) of the substrate (13) for making a temporary electrical connection with a contact card reader device;

   - an electronic chip (17) is attached to the substrate (13);

   - a first end of at least one wire (18) is connected directly to a connection pad of the chip (17), and the chip (17) and the first end of said wire (18) are encapsulated in a resin (25), characterized in that said wire (18) is intended to make a connection directly between the electronic chip (17) and an antenna (6) and that a second end of said wire (18) is left outside the resin (25).
2. Method according to Claim 1, comprising a step in which the second end of said wire (18) is fixed to a transfer pad (19) through a connection well (16) previously made through the substrate (13).
3. Method according to Claim 2, in which a cut is made around the chip (17) connected to the first end of said wire (18), this cut delimiting a module (2) and defining the final dimensions of the singulated module (2), and the connection well (16), in which the second end of said wire (18) is fixed, being located outside the module (2) after cutting.
4. Method according to one of the preceding claims, comprising a step in which a hot-melt material (20) is applied to the second face (15) of the substrate (13), such that one portion (23) of said wire (18) is accessible and another portion is held between the substrate (13) and the hot-melt material (20).
5. Method according to Claim 4, in which a window (23) has been made in the hot-melt material (20), leaving said wire (18) accessible through the window (23).
6. Method according to Claim 4 or 5, comprising a step in which the module (2) is singulated by dicing it according to its final dimensions, the portion (23) of said wire (18) that is left accessible being then located on the singulated module (2).
7. Method for producing a chip card (1) comprising:

   - the production of a module (2) in accordance with the method according to one of Claims 1 to 6, this module comprising a substrate (13) having a first (14) main face and a second (15) main face, with contacts (12) for making a temporary electrical connection with a contact card reader device on the first face (14) of the substrate (13), and comprising an electronic chip (17) attached to the substrate (13);

   - the production of an antenna (6) on a carrier (4), this antenna (6) comprising two ends, each equipped with a connection land (7);

   - the production of a cavity (11) in at least one layer (5) of the card (1) at least partially covering the carrier (4), in order to house the module (2) and to expose the connection lands (7) of the antenna (6), in which a portion (23) of said wire (18) is connected directly to a connection land (7) of the antenna (6).
8. Method according to Claim 7, in which the first end of said wire (18) is encapsulated in an encapsulation resin (25).
9. Method according to Claim 8, in which a portion (23) of said wire (18) is held, outside the encapsulation resin (25), at least partially on the substrate (13) using a hot-melt material (20).
10. Method according to one of Claims 7 to 9, in which a portion (23) of said wire (18) connected to the chip (17) is soldered to a connection land (7) of the antenna (6) by applying a thermode to a contact (12) located on the first face (14) of the substrate (13).
11. Chip card module comprising:

    - a substrate (13) having a first (14) main face and a second (15) main face, with contacts (12) on the first face (14) of the substrate (13) for making a temporary electrical connection with a contact card reader device;

    - an electronic chip (17) fixed to the substrate (13);

    - at least one wire (18) connected, by a first end, to a connection pad of the chip (17), in which the chip (17) and the first end of said wire (18) are encapsulated in a resin (25), characterized in that said wire (18) is intended to make a connection directly between the electronic chip (17) and an antenna (6) and that a portion (23) of said wire (18) extends out of the resin (25).
12. Module according to Claim 11, comprising a layer of hot-melt material (20) applied to the second face (15) of the substrate (13) while leaving at least one portion (23) of said wire (18) uncovered by the hot-melt material (20).
13. Chip card comprising a module (2) according to either of Claims 11 and 12, with a chip (17), and an antenna (6), said module comprising at least one wire (18) having a first end connected directly to a connection pad of the chip (17) and a portion (23) connected directly to a connection land (7) of the antenna (6).
14. Chip card according to Claim 13, in which the first end of said wire (18) is encapsulated, with the chip (17), in a resin (25) and a portion (23) outside the encapsulation resin (25) is soldered, through an opening (22) made in a hot-melt sheet (20), to a connection land (7) of the antenna (6).