DE20105170U1 - smart card - Google Patents

Description

The present invention relates to a chip card or a so-called chip card inlay as an intermediate product in the production of chip cards.

In the case of contact or contactless chip cards, the semiconductor chip is supplied with energy via an antenna coil, which is also used for data transfer. When producing such contact or contactless chip cards, the chip and the antenna coil are attached to a common substrate and electrically connected to one another to form a so-called chip card inlay. Various methods are known for producing these chip card inlays, particularly with regard to the production and attachment of the antenna coil.

For example, EP 0 753 180 B1 describes a method in which the coil is manufactured by laying the coil wire directly on the substrate and connecting it to the substrate, for example, by thermocompression or ultrasound. However, this method has the disadvantage of a low production speed, since the wire coils are laid one after the other on the approximately 20 to 30 substrates, each of which is placed in a

Substrate sheets must be laid together.

In addition, it is known from WO 91/16718 to prefabricate the wire coils as so-called winding coils and then attach these pre-products to the substrate. However, the use of such winding coils requires complex coil handling during feeding and application of the coils in order to position and fix them precisely on the substrate.

The object of the present invention is therefore to provide a chip card or a chip card inlay of the type mentioned at the beginning, which enables simplified production.

This object is achieved according to the invention in that the coil is provided on a flat carrier and the chip is attached to the substrate and the flat carrier with the coil is attached to the substrate with electrical contact between the chip and the coil. The coil can be produced using an etching process, but a wire coil is expediently used.

According to the invention, the coil is not provided directly on the substrate as in the process known from EP 0 753 180 B1, but is attached to a flat carrier, for example a PVC film, in a separate operation. This flat carrier with the (wire) coil provided on it is dimensionally stable and can

can therefore be transported and positioned and fixed on the substrate with little handling effort, thus simplifying substrate production.

In particular, the chip card according to the invention also enables a manufacturing variant in which a large number of coils are attached to a carrier material sheet, a corresponding number of chips are attached to a substrate sheet and the two sheets are then joined together to simultaneously form several chip card inlays. With this variant, a large number of chip card inlays can be completed simultaneously in parallel manufacturing, which can reduce production costs.

According to a preferred embodiment of the invention, a wire coil is laid on the flat carrier using the direct laying method and is connected to it at least in some areas. The wire coil can also be embedded in the material of the flat carrier, for example by means of thermocompression and/or ultrasound, with the embedding expediently taking place in such a way that the coil wire is completely surrounded by the carrier material. This achieves electrical insulation of the coil wire on the one hand and also protects the coil wire against contamination on the other.

In this embodiment, it can be provided that the connection areas of the wire coil are separated from the

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The carrier top side is pressed through to the carrier bottom side, forming a second laying plane, so that when the carrier is placed on the substrate they contact the chip provided thereon. The same procedure can be used for crossing winding sections of the wire coil, in that one of the winding sections is provided on the carrier top side and the other winding section is pressed through to the carrier bottom side, so that the winding sections are positioned in two laying planes and separated from one another by the carrier material.

According to a further embodiment of the invention, a window associated with the chip is provided in the flat carrier, for example punched in, and the flat carrier is attached to the substrate in such a way that the chip is at least essentially positioned in the window. This results in a flat overall height of the chip card inlay and an essentially flat surface. The wire coil can be attached to the flat carrier in such a way that its connection areas protrude into the window of the carrier and the electrical contact between the connection ends of the wire coil and corresponding connection lugs of the chip takes place when the carrier is attached to the substrate.

Alternatively, it can be provided that the wire coil is attached to the flat support in such a way that its connection areas protrude into the window or span it and the connection areas pass through the window

are placed towards the underside of the carrier and connected to it.

The wire coil is preferably made of silver-coated copper wire, which enables long transmission ranges to be achieved.

With regard to further advantageous embodiments of the invention, reference is made to the subclaims and the following description of an embodiment with reference to the accompanying drawing. In the drawing:

Fig. 1 shows a chip card inlay according to the present invention in plan view,

Fig. 2 shows a schematic side view of a chip card inlay from Figure 1,

Fig. 3 schematically shows the joining of carrier and substrate according to the method according to the invention,

Fig. 4 shows a sectional side view of the structure of another chip card inlay according to the present invention, and

Fig. 5 shows a carrier of another embodiment of a chip card inlay viewed from below.

The drawing shows a chip card inlay according to the present invention. This chip card inlay has a flat substrate 1 made of a flexible, non-conductive material such as PVC, which carries a chip 2 with two connection lugs 2a, 2b. In the embodiment shown, the chip 2 is attached to the flat surface of the substrate 1, but it is also possible to insert the chip 2 into a recess in the substrate 1 or to embed the chip 2 in the substrate 1, for example using a thermocompression process. The term chip also refers not only to the semiconductor components themselves, but also to so-called chip modules, i.e. semiconductor chips with the connection lugs 2a, 2b embedded in a plastic mass.

The chip card inlay further comprises a wire coil 3 which, according to the invention, is essentially completely embedded in an elastic, electrically insulating flat carrier 4 in the form of a PVC film which is attached to the substrate 2. In Figure 2 it is clearly visible that a window 5 is punched into the carrier 4, into which the chip 2 engages with its connection lugs 2a, 2b on the one hand and into which the connection ends 3a, 3b of the wire coil 3 protrude on the other hand and are connected to the connection lugs 2a, 2b, here glued.

This chip card inlay is manufactured as follows:

First, the chip 2 is attached to the substrate 1. At the same time, the wire coil 3 is embedded in the carrier 4 by laying the coil wire directly on the top side 4 of the carrier and pressing it into the thermoplastic PVC material of the carrier 4 under the influence of heat and pressure. The wire coil 3 is laid in such a way that the electrical connection ends 3a, 3b protrude into the window 5 and, when the carrier 4 is later attached to the substrate 1, contact the connection lugs 2a, 2b of the chip 2. The flat carrier 4 is then positioned with its underside on the substrate 1 in such a way that the chip 2 placed on the top side of the substrate protrudes into the window 5 and its connection lugs 2a, 2b come into contact with the connection ends 3a, 3b of the wire coil 3 and can be connected to them using an electrically conductive adhesive 6 or during a later lamination process. This process is comparatively simple since the preliminary product consisting of carrier 4 and wire coil 3 is dimensionally stable and therefore easy to transport and handle.

According to the invention, the precursors consisting of substrate 1 and chip 2 on the one hand and carrier 4 with embedded wire coil 3 on the other hand are not manufactured individually, but rather, as indicated in Figure 3, sheets 7 with a plurality of substrates 1 and chips 2 arranged thereon as well as carrier material sheets 8 which contain a corresponding number of carriers 4 with punched window 5 and embedded wire coil 3

and these sheets 7, 8 are then joined together to simultaneously form a plurality of chip card inlays.

Figure 4 shows the structure of another chip card inlay according to the present invention. Like the previously described embodiment, this consists of a substrate 1 with a chip 2 attached to it and a flat carrier 4 in the form of a PVC film in which the wire coil 3 is embedded. The wire is again laid on the carrier 4 from the top of the carrier using the direct laying method and embedded in it by thermocompression, whereby in the areas where winding sections 3c, 3d overlap, one of the winding sections 3c lies on the top of the carrier and the other winding section 3d is pushed through from the top of the carrier to the bottom of the carrier, so that two laying levels are formed. Furthermore, the wire coil 3 is laid in such a way that its connection areas 3a, 3b span the window 5 in the carrier 4, so that the connection areas 3a, 3b can be guided from the top of the carrier to the bottom of the carrier and connected to it after being severed in the manner shown.

In this embodiment, the size of the window 5 is selected such that the chip body can be inserted into the window 5, but the connection lugs 2a, 2b of the chip 2 come to lie outside the window area between the substrate 1 and the carrier 4 and the connection areas 3a,

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3b of the wire coil 3 contact the connection lugs 2a, 2b when the carrier 4 is placed on the substrate 1.

Yet another alternative is shown in Figure 5. In this embodiment, the wire coil 3 is again laid on the carrier 4 using the direct laying method from the carrier top side using the thermocompression method, with the connection areas 3a, 3b being pushed through the carrier 4 to the carrier bottom side so that the connection lugs 2a, 2b of the chip 2 contact the connection areas 3a, 3b when the carrier 4 is placed on the substrate 1.

Claims (11)

1. Chip card with a transponder unit which has at least one chip ( 2 ) and a coil ( 3 ), the connection regions ( 3a , 3b ) of which are electrically connected to the connection lugs ( 2a , 2b ) of the chip, characterized in that the coil ( 3 ) is attached to a flat carrier ( 4 ) made in particular of PVC and the chip ( 2 ) is attached to a substrate ( 1 ) and the flat carrier ( 4 ) is fastened to the substrate ( 1 ). 2. Chip card according to claim 1, characterized in that the coil is a wire coil ( 3 ) laid in particular directly on the carrier ( 4 ). 3. Chip card according to claim 2, characterized in that the wire coil ( 3 ) lies essentially on the upper side of the carrier and the carrier ( 4 ) lies with its underside on the substrate ( 1 ). 4. Chip card according to claim 2 or 3, characterized in that the wire coil ( 3 ) is completely surrounded by the carrier material at least over part of its length. 5. Chip card according to one of claims 2 to 4, characterized in that the chip ( 2 ) is at least partially positioned in a window ( 5 ) of the flat carrier ( 4 ). 6. Chip card according to claim 5, characterized in that the connection areas ( 3 a, 3 b) of the wire coil ( 3 ) protrude into the window ( 5 ) and the electrical contact with the chip ( 2 ) takes place in the window ( 5 ). 7. Chip card according to claim 6, characterized in that the electrical contact between the wire coil ( 3 ) and the connection lugs ( 2a , 2b ) of the chip ( 2 ) takes place outside the window area between the carrier ( 4 ) and the substrate ( 1 ). 8. Chip card according to claim 7, characterized in that the connection ends ( 3 a, 3 b) of the wire coil ( 3 ) are folded through the window ( 5 ) from the upper side of the carrier to the lower side of the carrier. 9. Chip card according to one of claims 16 to 7, characterized in that the wire coil ( 3 ) has crossing winding sections ( 3 c, 3 d) and that in these crossing regions one winding section ( 3 c) lies on the upper side of the carrier and the other winding section ( 3 d) on the lower side of the carrier, forming a second laying plane. 10. Chip card according to one of claims 1 to 9, characterized in that the connection areas ( 3 a, 3 b) are pressed through to the underside of the carrier. 11. Chip card according to claim 10, characterized in that the wire coil ( 3 ) is embedded at least over part of its length in the material of the flat carrier ( 4 ), in particular by means of thermocompression and/or ultrasound.