DE19630049A1 - Chip card with a contact zone and method for producing such a contact zone - Google Patents

Abstract

The contact surfaces of metal contacts (7) of a smart card are at least partially provided with an electrically conductive layer (11) which is arranged on the contact zone (5) so that there is no short-circuit in relation to the contacts. The contact surfaces are therefore used not only as functional surfaces for contacting but also as information carriers corresponding to the external outline of the conductive layer (11).

Description

The invention relates to a chip card with an inte card-containing circuit on which at least one main area a contact zone with several spaced apart metallic contacts, which with the integrated circuit are electrically connected is arranged and a method for producing such Contact zone.

Chip cards have been known for a long time and are used e.g. B. at frequent public telephone systems, as identification cards or the like used on a large scale. Meanwhile exi bull standards, the dimensions and technical details of such chip cards. These standards are at for example ISO 7810 and ISO 7816.

The chip cards with integrated circuit, which in one Card carrier is integrated, have a contact zone, the eight contacts according to the standards mentioned sees. The arrangement of these contact areas on the chip card is clearly defined by the standards mentioned. The con Clock zones of the card modules currently consist of suitable ones metallic functional surfaces, for example made of AU, NiPdAg or the like are produced. The individual con The tact surfaces of the contacts are separated by channels for example, by appropriate etching structures that, realized. The external design of the contact zone will due to the geometry of the etching contours of the ISO standards mentioned.

Although different structures of the contact zones are possible, insofar as the requirements of the ISO standards mentioned are met,  are made from chip card modules for economic reasons usually provide the same modules, i. H. the same Contact zones with connected integrated circuit the customers shipped. A distinction between the individual Chip card modules according to their manufacturer is only possible if their contact zones are designed differently. Like this far, the contact zones of different manufacturers are identical are formed, it is based on a chip manufactured later card with inserted chip card module, d. H. Contact zone and integrated circuit, no longer possible to determine from which chip card module manufacturer the chip card modules come.

The invention has for its object to provide a chip card specify a contact zone that is not only a functional area che but also serves as an information carrier.

This task is there with the chip card mentioned at the beginning solved by that the metallic contacts at least partially are provided with an electrically conductive layer, the electrically conductive layer with respect to the con is arranged short-circuit-free on the contact zone and a different color from the contacts points.

The method of making a contact zone for a he Chip card according to the invention has the following method steps on:

• - Providing a known contact zone for a Chip card,
• - Application of an electrically conductive layer on the Contact zone, the layer being limited and / or below broken is that the contact areas of the individual contacts remain short-circuit-free in the contact zone.

It is within the scope of the invention to the mentioned electrical conductive layer to apply another layer. This According to the invention, another layer serves as a protective layer and is also electrically conductive. This protective layer will advantageously transparent or at least largely designed transparently, so that the underlying one, arbitrarily colored, electrically conductive layer for the user the chip card remains recognizable.

In a development of the invention, the is electrically conductive capable layer so colored that a clear contrast to the underlying metallic layer of the contact surfaces consists. This makes it possible, for example, in a simple manner Lich, a company logo or the like with the help of elek tric conductive layer on the contact zone of the chip card to apply. The contact zone of the chip card can thus be marked as In serve formation carrier, which indicates, for example, by which chem chip manufacturer the chip card module comes.

It is understood that the contact on the contact surfaces zone applied layer and any applied above brought protective layer are electrically conductive, thus when using the chip card, d. H. when inserting the Chip card in a chip card reader, perfect contact is still guaranteed at the contact surfaces. It is therefore make sure that the electrically conductive Layer and the possibly applied electrically conductive protective layer as low as possible electri surface resistance.

It has proven to be useful for such materials the electrically conductive layer and electrically conductive Provide protective layer that has an electrical surface have a resistance of 40 Ω / ². The layer thickness of a sol Chen layer can be, for example, about 10 microns.  

The electrically conductive layer and possibly over it lying electrically conductive protective layer can, for. B. by a tampon printing process, spraying, rolling up, pricking a screen printing process or the like the.

In addition, it has proven to be beneficial to the one individual process steps for a subsequent heat treatment undergo. This can affect the quality or liability of applied electrically conductive layers clearly ver be improved.

The requirements for the electrically conductive layer or electrically conductive protective layer are essentially fol gend:

• - good conductivity,
• - relatively small layer thickness,
• - The protective layer should have a high hardness or a high Have wear resistance,
• - should adhere well to the underlying substrate be assured.

When applying the electrically conductive layer on the Contact zone of the chip card must, as when applying the elec tric conductive protective layer on the underlying electrically conductive layer, of course, be ensured that the contacting of the individual contact surfaces of the Kon the contact zone continues to be clocked by a chip card reader is guaranteed.

So that contact is possible at all, it is after the invention imperative that the electrically conductive layer and the electrically conductive protective layer as much as possible low surface resistance and thus high conductivity show speed. It is also important to ensure that the, e.g. B. by an etching structure, separate Kon  tact areas of the contact zone through the overlying elec trically conductive layer or electrically conductive protection layer are not short-circuited.

According to a development of the invention, this makes it is enough that the electrically conductive layer or the elec tric conductive protective layer, consisting of several ge separated layer elements, each layer element within a contact area of the respective contact is arranged.

It is within the scope of the invention that on the one hand not velvet Liche contact surfaces of the contacts and on the other hand the Kon tact areas themselves not completely of a layer element the electrically conductive layer are covered. Depending on Appearance of the z. B. Logos to be applied to the contact zone or marking, the layer elements can single con not at all and other contact areas only partially cover.

It is within the scope of the invention that the contact surfaces of the Contacts electrically separated from each other by separation channels are arranged and that the electrically conductive layer and the possibly overlying electrically conductive protective layer is interrupted above the separation channels.

The electrically conductive layer and the electrically conductive Protective layer z. B. a carbon paint or the like be.

The invention is described below in connection with several Figures explained in more detail using an exemplary embodiment. It demonstrate:

Fig. 1 is a perspective view of a chip card with a contact zone according to the invention.

Fig. 2 shows an embodiment of a conventional contact zone for a chip card.

Fig. 3 The top view of the contact zone of Fig. 2 with additionally applied, electrically conductive layer to represent a company logo.

Fig. 4 shows a section through the contact zone of Fig. 3 along the section line IV-IV.

Fig. 5 A for applying the insulating mask electrically conductive protective layer on the contact zone as shown in FIG. 3 and 4.

Fig. 6 shows an exemplary mask for applying the company logo according to Fig. 3 on the contact zone.

Fig. 7 A possible insulating mask for applying a protective layer on the contact area of FIG. 3.

Designate in the following figures, unless otherwise indicated, same reference numerals, same parts with the same Meaning.

In Fig. 1 a known smart card is shown in perspective view. The chip card has a z. B. made of plastic card carrier 3 , the check has card format. The chip card is identified by reference number 1 . On the main surface of the card carrier 3 facing the viewer, an approximately square-shaped contact zone 5 is arranged, which has eight contacts. On the contact zone 5 , an electrically conductive layer 11 is partially applied, which serves as a display surface in order to convey a certain meaning to the viewer of the contact zone, depending on the type and design of the electrically conductive layer.

In Fig. 2 ei ne conventional contact zone for a chip card is shown in an enlarged view and top view. The contact zone 5 has a total of eight contacts which are electrically separated from one another by separation channels 9 . The generally square contact zone 5 has at its lower edge four adjacent, also square contact surfaces 7 , which are separated from one another by separation channels 9 . At the top of the contact zone 5 four separate from each other by separation channels 9 are also con tact surfaces of four contacts 7, wherein the leftmost contact 7 is L-shaped zone in the center of the clock Kon 5 extends.

According to the invention an electrically conductive layer 11 is applied to this contact zone 5 , which is designed in comparison with the contact zone 5 with a different color. If the contact zone 5 according to FIG. 2 consists of brass or copper or is gold-plated, the electrically conductive layer can be chosen blue, green or similar, so that a good contrast between the electrically conductive layer 11 and the contact zone 5 underneath is guaranteed .

However, colors such as white or red are also possible, whereby in advantageously a carbon varnish doped with color pigments becomes. Here you can choose TiO₂ for white and purple for red and thus a particularly inexpensive coloring will hold.

In Fig. 3, the contact zone of Fig. 2 is Darge again. However, the electrically conductive layer 11 according to the invention has now been applied. In the present exemplary embodiment, the outer boundary of the electrically conductive layer 11 is in the form of an “S”, this “S” extending at least partially into all contact surfaces of the contacts 7 . As shown in FIG. 3, the electrically conductive layer 11 is interrupted at precisely the points at which the separation channels 9 of the contact zone 5 are also located. This ensures that the electrically conductive layer 11 does not cause a short circuit between the individual contacts 7 .

In the embodiment of Fig. 3, the mentioned interruptions of the electrically conductive layer 11 ensure that a total of nine layer elements 13 form the entire electrically conductive layer 11 .

FIG. 4 shows a sectional view of the contact zone from FIG. 3. The contact zone is delimited on the left and right by two separation channels 9 . A metal layer, which forms the contact 7 , is located between these two separation channels 9 . The electrically conductive layer 11 is arranged above this contact 7 , this electrically conductive layer 11 not reaching as far as the two separating channels 9 in accordance with the boundary of the "S" in FIG. 3. Over the electrically conductive layer 11 , an electrically conductive protective layer 15 is attached, which preferably has a high hardness or a high level of wear resistance. This electrically conductive protective layer 15 is optionally and expediently transparent so that the underlying electrically conductive layer 11 , which is intended to convey a certain meaning as information carrier, remains recognizable.

FIG. 5 shows an insulating mask 21 with which the separating channels 9 of the contact zone 5 from FIG. 2 can be covered in order to subsequently apply the electrically conductive layer 11 using a suitable method. The insulating mask 21 is designed in such a way that the separating channels 9 which can be seen in FIG. 2 are reliably covered. The insulating mask 21 is designed in such a way that the individual separation channels 9 of the contact zone 5 are slightly overlapped on the left and right. This insulating mask 21 is placed on the contact zone 5 of FIG. 2 and then the electrically conductive layer, for. B. a carbon lacquer, applied. This can be done by pad printing, screen printing, spraying, rolling, stamping or the like.

It has proven to be advantageous to provide one or more cleaning steps before the application of the electrically conductive layer 11 , with which the surface of the contact zone 5 is freed of dirt particles. This improves the electrical contact between the electrically conductive layer 11 and the contact zone 5 .

In Fig. 6, an information mask 23 is exemplified Darge to apply the "S" shown in Fig. 3 on the Kontaktzo ne 5 . Instead of such an information mask 23 , any mask can be provided.

In order to increase the abrasion resistance of the electrically conductive layer 11 , as already mentioned in connection with FIG. 4, an electrically conductive protective layer 15 can be applied to the electrically conductive layer 11 . This protective layer 15 is designed to be transparent. In Fig. 7, a suitable insulating mask 25 is shown, with which the protective layer 15 on the contact zone 5 together with the applied, electrically conductive layer 11 , can be applied. The insulating mask 25 in FIG. 7 corresponds in its design to the insulating mask 21 from FIG. 5.

Claims (11)

1. Chip card with an integrated circuit ent holding card carrier ( 3 ), on the at least one main surface of a contact zone ( 5 ) with a plurality of mutually spaced metallic contacts ( 7 ) which are electrically connected to the integrated circuit, is arranged, characterized that the me-metallic contacts (7) are at least partially provided with an electrically conductive layer (11), wherein the electrically conductive layer (11) short free of is sorted with respect to the contacts (7) on the contact zone (5) and a has different coloring from the contacts. 2. Chip card according to claim 1, characterized in that the electrically conductive layer ( 11 ) consists of several mutually separate layer elements ( 13 ), each layer element ( 13 ) being arranged within a contact surface of the respective contact ( 7 ). 3. Chip card according to claim 2, characterized in that the contact surfaces of each contact ( 7 ) of the contact zone ( 5 ) by a layer element ( 13 ) of the electrically conductive layer ( 11 ) are at least partially covered. 4. Chip card according to claim 2 or 3, characterized in that the contact surfaces of the contacts ( 7 ) by separation channels ( 9 ) are electrically separated from each other net, and that the electrically conductive layer ( 11 ) over the separation channels ( 9 ) is interrupted . 5. Chip card according to one of claims 1 to 4, characterized in that the electrically conductive layer ( 13 ) is a carbon lacquer. 6. Chip card according to one of claims 1 to 5, characterized in that a transparent electrically conductive protective layer ( 15 ) is applied over the contact surface of the contacts ( 7 ) and applied electrically conductive layer ( 11 ), wherein the electrically conductive protective layer ( 15 ) with respect to the contacts ( 7 ) is also short-circuit-free on the contact zone ( 5 ) is arranged. 7. Chip card according to one of claims 1 to 6, characterized in that the electrically conductive layer ( 11 ) and / or the electrically conductive protective layer ( 15 ) has a thickness of at least approximately 10 microns. 8. A method for producing a contact zone for a chip card according to one of claims 1 to 7, characterized by the method steps:

• - Providing a contact zone ( 5 ) known per se for a chip card ( 1 );
• - Applying an electrically conductive layer ( 11 ) to the contact zone ( 5 ), the electrically conductive layer ( 11 ) being limited and / or interrupted such that the contact surfaces of the individual contacts ( 7 ) of the contact zone ( 5 ) remain short-circuit-free.

9. The method according to claim 8, characterized in that on the electrically conductive layer ( 11 ) an elec trically conductive, transparent protective layer ( 15 ) is brought, wherein this protective layer ( 13 ) is limited and / or interrupted so that the Contact surfaces of the individual contacts ( 7 ) of the contact zone ( 5 ) remain short-circuit-free. 10. The method according to claim 8 or 9, characterized in that the electrically conductive layer ( 11 ) and / or electrically conductive protective layer ( 15 ) is applied by a printing, spraying, rolling or stamping process. 11. The method according to any one of claims 8 to 10, characterized in that before the application of the electrically conductive layer ( 11 ) on the contact zone ( 5 ) the latter is subjected to one or more cleaning steps.