CH619310A5 - Portable card for signal processing system and method of manufacturing this card - Google Patents

Abstract

The card (10) is made as a sheet (12) complete with embossings (16), thin elements (18) including particular references of the holder of the card. It is fitted with a hole (20), into which an integrated circuit (22) is inserted. The latter is surrounded by a network of conductors (24) provided respectively with contact regions (26). The circuit and the network rest on the same substrate (28) which is thinner than the sheet (12) and which is attached to the latter. Recesses (34) are formed in the sheet (12) at the site of the contact regions (26) so that contact can be established with the contact regions (26), by external electrodes. This card is obtained by cutting it out of a strip which unwinds and on which substrates equipped with the integrated circuit have been mounted in advance. In this way a card of simple construction is obtained, allowing an extension of the information normally produced with such cards. <IMAGE>

Description

The invention relates to a portable card for a signal processing system, as well as to a method for manufacturing such cards.

In most of the fields where an element can give a person reserved access to a system, this element is increasingly constituted by a portable card. This is the case, for example, with credit cards, which have already been used for twenty years and are now widely used.

Recently, the International Standards Organization has ruled on. dimensional characteristics of credit cards (ISO / DIS 2894 standard): standard cards have the shape of a rectangle of 85.72 mm X 55.98 mm, with 0.762 mm thickness; the alpha-numeric characters which are intended for example to indicate the name and the address of the person to whom the card belongs can be embossings whose height compared to one of the surfaces of the card must not exceed 0.50 mm about.

In the cards currently in force, information other than these alpha-numeric characters and which is intended to give the card holder access to an electrical signal processing system is contained only in pre-recorded magnetic tapes, attached to the card. If for certain applications the content of these bands is sufficient, for other applications on the contrary, for example credit cards, an extension of the information, or even the incorporation in the card of processing circuits capable of dialoguing with the processing system of signals and possibly incorporating a memory, would offer great advantages. With such circuits, credit cards could in particular carry out all debit and / or credit operations in cooperation with the processing system, and record the results of these operations.

Several researches have already been undertaken in this direction, trying to incorporate into the card an integrated circuit device. But problems arise for such an application to credit cards: their small thickness required by international standard (0.762 mm) must still be sufficient to contain the integrated circuit device capable of performing the above operations, while a certain flexibility of the card must be respected without endangering the operation of the device.

Several embodiments of integrated circuit credit cards are already known. According to one of these modes, the capsule containing the integrated circuits is connected to a network of conductors formed on a rectangular sheet of given length, the conductors ending in contact pads over a width of the sheet; a second sheet, having the thickness of the capsule, including an opening of the same length and width of the capsule, and having a shorter length than that of the first sheet in order to leave the contact areas up to date

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mentioned above, is arranged on the first sheet by enclosing the capsule; finally a third sheet, having the same length and the same width as the second, covers the second sheet and the capsule.

This method of making a credit card has the disadvantage of involving three sheets of different configurations, which must be superimposed correctly, then stick or weld. In addition, for this card to meet the aforementioned standards, the set of three sheets must not exceed the thickness of 0.762 mm, so that the sheets must be thin, therefore not very easy to handle, the capsule must be very thin, and welding or gluing must use special techniques.

According to another known mode, the card is produced in two sheets only. On the first sheet, provided on one of its faces with a network of conductors ending in as many external contact pads, is arranged the integrated circuit device. The second sheet is arranged above, but in order for the card to include said device, the two sheets are made of a softening material at a high temperature, so that, by heating at this temperature, the two sheets are welded incorporating the device . This assembly therefore requires the use of two sheets, made of a material with well-defined properties, then controlled welding at high temperature, which could jeopardize the condition of the device.

The present invention overcomes all these drawbacks.

The portable card according to the invention is defined in the claim.

Also, a card according to the invention can only comprise a single sheet, having an open or closed cavity in which the device can take place. The fact that the device and its network of conductors are already installed on a substrate benefits the manufacturing process and its cost. On the other hand, we take advantage of the tolerated thickness of the reference characters made by embossing (0.5 mm), by introducing the integrated circuit device into a cavity which can itself be made by the same embossing as the characters of reference in a part of the card allowed for the placement of these characters, or which may be included in a medium whose total thickness is equivalent to the nominal thickness of the card (0.762 mm) added to the height of the characters (0 , Approx. 48 mm).

The invention also relates to a method of manufacturing a card according to the invention, which is defined in claim 14.

This process is therefore simple. It only uses proven techniques: for example, each aforementioned wafer can come from the same ribbon carrying on a same substrate a series of networks of conductors provided with their corresponding device; moreover, this substrate, which will occupy for the most part only a small surface in comparison with the total surface of the card, can easily and efficiently be soldered by known high-frequency soldering techniques. It will also be seen that the conventional bonding methods are just as advantageous.

Several particular embodiments of the subject of the invention will be described with reference to the accompanying drawing:

- Figure 1 is an exploded perspective view of a card produced according to a first embodiment;

- Figure 2 is a sectional view taken along line II-II of the card of Figure 1;

FIG. 3 is a sectional view of a card produced according to a second embodiment:

- Figure 4 is a sectional view of a card according to the invention produced according to a third embodiment;

- Figure 5 is a bottom view of the card shown in Figure 4, the cover 50 removed;

- Figures 6 and 7 are sectional views of cards according to the invention respectively corresponding to fourth and fifth embodiments;

- Figure 8a is a sectional view of a card according to the invention at the external contact terminals of the signal processing device incorporated in the card;

- Figure 8b is a partial view of the substrate corresponding to the assembly of Figure 8A;

- Figures 9a and 9b are views respectively similar to Figures 8a and 8b, illustrating an alternative embodiment according to the invention of the contact terminals;

- Figure 10 is a sectional view of another alternative embodiment of the contact terminals; and

- Figure 11 is a figure schematically illustrating an apparatus implementing a method of manufacturing a card according to the invention.

The exemplary embodiment considered in the description which follows is the standardized credit card. By the aforementioned constraints that standardization imposes, it constitutes an element of choice to bring out better the characteristics and advantages of the invention.

We will first refer to Figures 1 and 2. In these figures, the card 10 according to the invention is formed by a rectangular sheet 12 meeting the above international standards: 85.72 mm in length, 53.98 mm thickness, and 0.762 mm thick, and its material is made of PCV (polyvinyl chloride) or PVCA (polyvinyl chloride co-vinyl acetate) laminated, or of a material which has equivalent or better operating characteristics and which is suitable for stamping.

In accordance with the standard, a part 14a of the card, lying between one of its two lengths and a parallel 15 thereto, represented by a broken line in FIG. 1, is left for the display of references, such as for example the name and address of the card holder.

These references can be alpha-numeric characters made by embossing, such as the reference characters 16 indicated in FIGS. 1 and 2. These references can also be written on a thin element, of paper for example, glued on the surface part. 14a of the card 10, such as the element 18 shown in FIG. 1. In any case, the standard requires that the embossed reference characters 16 and the glued elements 18 do not exceed the height of about 0.50 mm relative to to the upper surface 12a of the card 10 where the references must appear. The permitted height of these characters is therefore substantially equal to two-thirds of the thickness of the sheet 12.

The sheet 12 is provided with a cavity 20 which, in this embodiment, is a hole passing through the sheet. This hole is shaped to contain an electrical signal processing device 22. This device is connected to a network 24 of conductors respectively provided with terminal pads 26.

The device 22 and the network 24 rest on the same substrate 28 of thickness relatively smaller than that of the sheet 12 of the card and of surface relatively smaller than that of the sheet 12. For example, the assembly forming the wafer 30 and comprising the device 22, the network 24 and the substrate 28, may be of the type described for example in French patents 2,205,800.2 299,724 and 2,311,406 of the licensee.

In fact, FIG. 2 shows that the hole 20 opens out through a shallow recess 32 formed on the face 12b of the card, which is its lower face. This recess 32 has a geometry corresponding to that of the substrate 28, and a slightly higher surface; its depth is determined so that the substrate lodges in the recess by presenting a surface of the same level as the surface 12b.

Furthermore, recesses 34 are made in the card

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at the contact pads 26 of the network conductors 24 when the substrate is housed in the card. In this embodiment, the recesses are holes passing through the sheet 12. These recesses are designed so that electrodes external to the card (not illustrated in FIG. 2) can come into electrical contact with the contact pads 26 of the plate 30.

In the embodiment illustrated in FIG. 2, the fixing of the plate 30 to the sheet 12 is carried out by an electrically insulating filling material 36, which fills 111 the hole 20 as described in FIG. 2. This material is substantially flush with the surface 12a in the case of FIG. 2, but it is possible that this material can rise up to the permitted height of the embossings 16; this possibility is advantageous in that it allows the use of large devices 22 s 1 s while adapting to the imposed thinness of the card.

It will also be noted that the substrate of FIG. 2 must in this case be made of a relatively rigid material. As a variant, a cover (not shown) made of a more rigid material than the substrate could be used under the same conditions as those in FIG. 4. Without the cover, the substrate 28 is glued or welded to the sheet 12.

A fundamental aspect of the present invention also resides in the fact that the device can advantageously be placed in a corner of the card, where the stresses to the -5 torsion of the card, made of a relatively rigid material, are of lesser intensity than those exercised in the central part of the card. This advantage is due to the fact that the substrate can occupy only a really small part of the card and that the contacts are directly available, by means of the recesses 34, of the electrodes, so that the conductors do not have to extend across the card and thus make it vulnerable to twisting or bending.

Another aspect in accordance with the present invention lies in the compatibility of a treatment by means of the device 22 and by other means such as magnetic tapes, which can be superimposed in a part 14b provided for by the international standard. This part is the complementary part of part 14a of the card 10, delimited by the broken line 15 drawn longitudinally on the card represented in FIG. 40

1. In accordance with the known technique, there is shown at 38 such a magnetic strip, generally attached to the lower surface 12b of the card. It can be seen in the example in FIG. 1 that neither the device 22 nor the network conductors 24 can, in a card according to the invention, interfere with 45 the area provided for the information recorded on magnetic tape.

FIG. 3 illustrates an alternative embodiment of a card according to the invention, according to which the plate 30 of the processing device 22 is disposed on the surface 12a of the card 50 10, instead of the opposite surface as in the case of the figure

2. This mounting offers several advantages over the one just described: given the admissible height which can be disposed above the surface 12a of the card 10 according to the regulations of the international standard, it is no longer necessary to practice a recess 55 such as recess 32 in the case of the figure

2; and even a cover 40, made for example of a more rigid material than that which constitutes the substrate 28 of the wafer 30, can cover the whole and better protect it. This results in easier construction and better protection. On the other hand, it will be noted that the recesses 34 provided for the electrical connections external to the card open onto the lower face 12b of the card. This does not change the availability of the device 22 with respect to the external electrical signal processing system with which the card is intended to enter into relationship.

Optionally, a cover 42 can close the hole 20 on the side of the face opposite to the face on which the plate 30 is disposed with its substrate 28. Of course, this cover could have intervened in the case of the card shown in FIG. 2 , the illustrated embodiments being to be considered only as nonlimiting examples.

It should also be noted that, for clarity of the drawings, the cover 40 is welded or glued to the card 10.

In the embodiment illustrated in FIG. 4, the cavity 20 is no longer a hole, but an embossing 44 of the sheet 12 constituting the card 10. This embossing has a height complying with the standard, that is to say at most equal to that of the embossings 16 (approximately 0.50 mm). As this height represents approximately 2/3 of the thickness of the card, the additional space represented by this embossing is far from negligible and offers multiple advantages. The device 22 is housed in the cavity 46 created by the embossing 44, while a first recess bearing 48 is provided for housing the substrate 28 of the wafer 30. As in the case of FIG. 3, a cover 50, equal to the cover 40 of Figure 3, can also be provided to stiffen the assembly.

A plate 30 like that illustrated in FIGS. 1 to 3 could be used, which would have had the consequence of opening the recesses 34 on the face 12a of the card. However, FIG. 4 illustrates another embodiment which can be adopted. In the case described in FIG. 4, the device 22 and the network 24 of conductors are no longer arranged on the same face of the substrate as in the case of FIGS. 1 to 3, but on either side of the substrate, like the shows better in Figure 5. In this way, it is the cover 50 which has the contact recesses 34. However, to prevent material such as dust or other very fine debris from becoming lodged in the recesses 34 and disturb the electrical connection connecting the device 22 to the processing system to which it is intended to be connected, an electrically conductive material 52 can fill these recesses. For example, this material can be a tin-lead mixture or a conductive polymer in particular.

Figure 5 shows the bottom view of the card illustrated in Figure 4, the cover 50 removed. The substrate of the wafer 30 has, according to this embodiment, a rectangular central opening 54 in which the conductors of the network 24 extend. On the extension of these conductors come to rest the respective output pads of the electric or electronic circuits 56 included in the device 22. The assembly described in FIGS. 1 to 3 differs from the latter by the absence of the window 54 and by the arrangement of the device 22-network 24 assembly on the same side of the substrate, this device being mechanically fixed. to said substrate by the face presenting the circuits 56, or by its opposite face, by a means other than the electrical connections of the device. The advantage of the wafer 30 in the cards described in Figures 2 and 3 lies in its simple implementation and improved safety, which can be further enhanced by the addition, on the surface of the circuits 56 of the device 22, of a substance cannot be removed from the device without damaging the operation of the circuit 56. This irreparably avoids any fraud. This substance has been represented for example in FIGS. 2 and 4 at 58 by the grid area located immediately below the device 22.

FIG. 6 illustrates, in the framework which has just been described, an alternative embodiment using a device 22 fixed to the network 24 by its face having the electrical or electronic circuits 56. In this case, the conductors of the network 24 must be arched to rise to the level of the upper face of the device where the processing circuits are held. In this case, the device and the network of conductors are based

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side of the substrate 28. We will also find in the card of FIG. 6 the substance 58 which cannot be removed from the device without damaging the operation of the circuits. Possibly, there is shown at 60 a coating material surrounding the device 22, as is moreover fair in all the others? case of figures.

A new fact also appears in the card of FIG. 6, namely that it is no longer composed of a single sheet, but of two sheets 62 and 64. As can be seen, the plate 30 is inserted between these two sheets, sheet 62 being previously embossed. During construction, the two sheets 62 and 64 are glued or welded together.

Figure 7 shows yet another embodiment according to the invention. This card no longer uses a single sheet 12, only perforated to form the recesses of the contacts 34. A plate 30 as described in FIG. 5 is placed on the face 12a of the plate. A cap 66 covers the device and the substrate. For this, it is slightly embossed so that, once welded to the sheet 12, the thickness of the card at the device is at most equal to that of the card: o at the embossings 16.

Of course, all of these embodiments which have just been described have only illustrated the various possibilities offered by an assembly in accordance with the invention. It is clear that their combination also falls within the scope of the invention.

The invention also presents means giving the assurance of a good electrical connection between the device 22 of the card and the system responsible for cooperating with this card. Figures 8 to 10 illustrate various alternative embodiments for obtaining this insurance. m

According to the assembly of FIGS. 8a and 8b, the same conductor 68 of the network 24 attached to the device 22 cooperates with two contact recesses 34a and 34b facing a wide contact area 26. Thus, two electrodes 70a and 70b are required in order to test the contact between each conductor 68 and the “processing system (not shown) to which the card is attached; a source 72 connected to said electrodes 70a and 70b applies between these two electrodes a predetermined voltage. If the contact is good, a predetermined current must pass through the two recesses 34a and 34b and the terminal area 26. 4 "

The assembly described in FIGS. 9a and 9b allows better detection of bad contacts which may occur at the level of the card. Each conductor 68 of the network 24 is here split into two conductors 68a and 68b each communicating, via their terminal range 26a and 26b, with respective recesses 34a and 34b formed in the card 10. At the level of the device 22, the electrical or electronic circuits 56 have for their external terminals pads 74, themselves split into 74a and 74b to which the conductors 68a and 68b respectively correspond. 50

By applying the electrodes 70a and 70b between them between the recesses 34a and 34b by means of the voltage source 72, a current which must exceed a certain predetermined threshold intensity must flow through a path including the terminal area 26a, the conductor 68a, the pad 74a, the connection connecting the pad 74a s5 and the pad 74b, the pad 74b, the conductor 68b, the terminal strip 26b, and the recess 34b. In this way, it is ensured that all the connections to the device 22 are healthy.

FIG. 10 shows another embodiment, according to which each conductor 68 ends in an end patch 26 which passes through the substrate through an opening 76 in the substrate 28, so that two end pads 26a and 26b are present on each of the two faces of the substrate. Two recesses 34a and 34b are respectively in connection with the areas 26a and 26b, so that by applying a predetermined voltage to the electrodes 70a and 70b, a current greater than a given value must flow so that good contact is made.

FIG. 11 very schematically illustrates an apparatus which can be used for the manufacture of a card according to the invention. This device will show a process that can be adopted for the manufacture of this card.

This method consists first of all in having a first winding 78 of a first strip 80 having a width at least equal to a dimension of the card, that is to say its length or its width. This first ribbon is of the material of the card, and if the latter comprises only one sheet, the ribbon 80 will have the standardized thickness of the card.

As the ribbon 80 unwinds, a forming apparatus 82 forms in this ribbon a plurality of equally spaced cavities 20. As we have seen, these cavities can be a hole or an embossing. They are represented by a dashed line in Figure 11.

On the other hand, a second winding 84 has a second strip 86 comprising a series of devices 22 provided with their network 24 of conductors. This tape conforms to the patent, which was cited above.

An assembly device 88 performs the cutting (represented by the arrow 90) of the second strip 86, in order to cut a wafer 30 as described above; this device also completes the introduction of each device 22 dan; each of the cavities 20 as the ribbon 80 unwinds, as well as the assembly of each plate 30 with the ribbon 86.

After the ribbon 80 has been cut along arrow 92, a card 10 according to the invention finally comes out.

Optionally, a third winding 94 of a third strip 96 can be used to constitute the aforementioned cover 40 or 50, by the section along the arrow 98 in the device 88. The cavity 20-plate 30-cover 40 assembly is illustrated schematically in the card 10 leaving the device 88.

In other cases, the third winding could constitute the second sheet 64, when the card to be manufactured is typt of that described in FIG. 6.

Note, of course, that the device 88 can use bonding as well as welding for the assembly of the constituent parts of the card, as we have seen above.

It is remarkable that, given the small extent of the plate 30 and / or of the cover 40 or 50 relative to the card 10, the latter can be effectively welded by its edges by proven conventional welding techniques, such as by high -frequency unlike welding, by these same techniques, large areas occupying for example substantially the surface of the card. This constitutes one of the great advantages which the invention presents over the known prior art.

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Claims (20)

619,310 2 1. Portable card for signal processing system, comprising at least one signal processing device disposed inside the card, and external contact terminals connected to said device by a network of conductors, characterized in that the card includes at least one sheet (12) provided with at least one cavity (20,46) and in that said device (22) and said network (24) of conductors (68) rest on the same substrate (28) having a smaller surface and thickness to those of the sheet (12) and constitute with this 1 " substrate a wafer (30), at least the device (22) of the wafer being housed in the cavity of the sheet and said contact terminals of the card being formed by contact pads (26) arranged on the substrate (28) . 2. Card according to claim 1, characterized in that the cavity is formed by an embossing (44) made in the sheet (12). 3. Card according to claim 1, characterized in that the cavity is a hole (20) passing through the sheet. 4. Card according to claim 1, characterized in that the cavity is formed by a cap (66) disposed on one face of the sheet and covering the wafer (30). 5. Card according to one of claims 1 to 4, characterized in that the cavity contains an electrically insulating filling material (36). 25 6. Card according to claim 1, characterized in that the face of the device (22) which includes electrical circuits (56) is in contact with a substance (58) which cannot be removed from this face without damaging the operation of the circuits. 7. Card according to claim 1, characterized in that the 1 (1 cavity houses the wafer and is closed by a cover (50). 8. Card according to claim 1, characterized in that the cavity houses the wafer and is closed by a second sheet (64) secured to the first sheet (12). 9. Card according to claim 7, characterized in that the contact pads (26) are respectively accessible through recesses in the cover (50). 10. Card according to claim 7 or 8, characterized in that the contact pads (26) are respectively accessible through recesses (34; 34a) in the sheet (12). 40 11. Card according to claim 9 or 10, characterized in that each contact pad is accessible from the same side of the substrate through two recesses (34a, 34b). 12. Card according to claim 1, characterized in that the device (22) is provided with output terminals (74) each divided into two zones (74a, 74b) connected respectively to two parts of contact pad (26a, 26b) respectively accessible by two separate recesses (34a, 34b). 13. Card according to one of claims 9 to 12, characterized 50 in that the recesses are filled with an electrically conductive material (52). 14. A method of manufacturing a card according to claim 1, characterized in that it consists in: having a winding (78) of a ribbon (80) having a width at least equal to the card (10 ); to have plates (30) comprising a substrate (28) provided with a device (22) for signal processing and its network (24) of conductors (68), to assemble each plate with the ribbon (80) of such so that the device (22) is housed in a cavity and to cut from the ribbon said card 60 (10). 15. Method according to claim 14, characterized in that the cavities (20,46) are formed in the ribbon, for introducing therein the devices (22) associated with the plates as and when 6s the ribbon (80) is unwound . 16. Method according to claim 14 or 15, characterized in that the plates are cut from a second strip (86). 17. The method of claim 16, characterized in that it consists in closing the cavity containing the wafer by means of a cover (40.50) or a second sheet (64) taken from a third ribbon (96 ). 18. Method according to claim 15, characterized in that the formation of the cavities consists in embossing at regular intervals the first strip (80). 19. Method according to claim 15, characterized in that the formation of the cavities consists in forming holes in the first strip. 20. The method of claim 15, characterized in that the formation of the cavities consists in applying, to each plate disposed on the first strip, a cap (66). 45 55