SE545307C2

SE545307C2 - Method and apparatus for producing a radio-frequency identification (rfid) transponder

Info

Publication number: SE545307C2
Application number: SE2151631A
Authority: SE
Inventors: Eerik Halonen; Juha Ikonen; Lauri Huhtasalo
Original assignee: Digital Tags Finland Oy
Priority date: 2019-05-29
Filing date: 2019-05-29
Publication date: 2023-06-27
Also published as: FI20216339A1; WO2020240252A1; SE2151631A1

Abstract

A method for producing radio-frequency identification (RFID) transponders arranged on a carrying substrate is disclosed, comprising: providing two substrate areas, each having at least one antenna element with antenna terminals arranged thereon; and providing a dual-sided integrated circuit (1C) having an antenna contact on each of two opposed external surfaces. The 1C is arranged on one of the substrate areas, so that one of the antenna contacts comes in mechanical contact with one of the antenna terminals. The two substrate areas are then brought together, thereby bringing the second antenna contact in mechanical contact with second antenna terminal. Finally, heat is applied to the substrate areas in the vicinity of the IC, heating it to a temperature at least equal to a characteristic melting point of the antenna terminals, thereby forming electric contact between the antenna contacts and the antenna terminals. A corresponding apparatus is also disclosed.

Description

METHOD AND APPARATUS FOR PRODUCING A RADIO-FREQUENCY IDENTIFICATION (RFID) TRANSPONDER Technical ﬁeld of the invention The present invention is related to a method and apparatus for production of a radio-frequency identification (RFID) transponder arranged on a carrying substrate.

Background RFID transponders used for a wide variety of purposes, such as for inventory, locate, identify, authenticate, configure, enable/disable and monitor items to which the tags are attached or in which the tags are embedded. RFID systems may be used in retail applications to inventory and track items, in consumer- and industrial-electronics applications to configure and monitor items, in security applications to prevent loss or theft of items, in anti- counterfeiting applications to ensure item authenticity, and in many, many other applications.

In conventional RFID transponders, the integrated circuit (IC) is provided with 2 to 4 bumps or pads at their bottom side. These pads or bumps are to be connected to the leads of the conductive antenna pattern. There is generally an increasing demand for smaller RFID transponders, and also an increasing demand for less costly RFID transponders. The RFID microchip is a major cost factor of the transponder, and the microchip cost is proportional to its size, and consequently there is also a need for smaller RFID microchips (IC:s). However, as the size of the IC's decreases, the assembly of the transponder, and in particular the placement of the IC to an antenna pattern, becomes more complicated, tedious and costly. Typically, the bumps or pads may have a size of about 50 or 60 microns, and the separation gap is typically 0.10-0.20 mm. The connection areas on the antenna conductor need to be equally closely arranged, and acceptable tolerances during manufacturing are extremely low.

Thus, the only available possibility to produce RFID transponders at relatively low cost is to use rather large lC:s, thereby enabling a relatively long separation between the bumps/pads, and thus enabling placement of the lC:s on the antenna pattern with somewhat less precision and with higher tolerances.

Also, if smaller lC:s are used, the gap between the connection areas of the antenna also needs to get smaller and this is very difficult and costly to achieve with current etching technology.

These strict requirements, in particular when relatively small lC:s are used, makes it necessary to use highly engineered and specialized automation equipment, which increases the overall production cost. Also, due to the strict requirements and low tolerances, it is difficult to obtain a high throughput, i.e. high UPH (Units Per Hour).

The only solution to this so far has been to use larger lC:s, but the material cost is correlated to the size, the cost savings with this approach are very limited. Further, for many applications there is a strong need for very small RFID transponders.

An alternative solution has been suggested in US 2014/0144992 and US 9489611. These documents disclose a solution where dual-sided lC:s are used, having a contact pad/bump on two different sides. Hereby, the antenna may be connected to the IC on two different sides. This solution reduces the tolerance problems, and enables use of smaller lC:s with relatively high alignment and attachment tolerances. On the other hand, the connection of the IC contacts to the antenna structure hereby become very complicated, and the production complexity and production costs are still very high.

There is therefore a need for a method and apparatus enabling production of RFID transponders in a less complex, faster and more cost- effective way.

Summary lt is therefore an object of the present invention to provide a method and an apparatus for producing RFID transponders arranged on a carrying substrate, such as RFID tags or labels, or intelligent packaging products, which at least alleviates the above-discussed problems.

This object is obtained by means of a method and an apparatus in accordance with the appended claims.

According to a first aspect of the invention there is provided a method for producing radio-frequency identification (RFID) transponders arranged on a carrying substrate, comprising: providing a first substrate area and a second substrate area, the first and second substrate areas each having at least one antenna element formed by an electrically conductive pattern arranged thereon, and preferably several antenna elements arranged sequentially thereon along a longitudinal extension of the first and second substrate areas, wherein a first antenna element arranged on the first substrate area has a first antenna terminal, and a second antenna element arranged on the second substrate area has a second antenna terminal; providing a dual-sided integrated circuit (IC) including a first circuit block electrically coupled to a first antenna contact, disposed on a first external surface of the IC, and a second antenna contact, disposed on a second external surface of the IC opposite the first external surface of the IC; arranging the IC on the first substrate area, whereby the first antenna contact comes in mechanical contact with the first antenna terminal; bringing the first substrate area and the second substrate area together, thereby bringing the second antenna contact in mechanical contact with the second antenna terminal; heating the first and second substrate areas in the vicinity of the IC to a temperature at least equal to a characteristic melting point of said first and second antenna terminals, thereby forming electric contact between the first antenna contact and the first antenna terminal, and between the second antenna contact and the second antenna terminal.

Electrically connecting the antenna contacts and the antenna terminals results in the antenna elements becoming electrically and operatively connected to the integrated circuit that is electrically connected to the contact pad. By "operatively connected" is here meant that the antenna element is operable as an antenna for the integrated circuit.

By the "characteristic melting point" is here meant the temperature at which the material in question begins to behave as a more or less viscous liquid. lf the material starts to melt at a well-defined temperature, then that temperature is the characteristic melting point. lf the material is a composite where two or more constituents remain separate in different particles and/or even within a single particle, the characteristic melting point is the temperature at which such a constituent melt that has a predominant effect on the creation of cohesion within the melt coming from a plurality of molten particles. lf the conductive material is homogeneous in composition and consist only of one metal or alloy that has a well-defined melting temperature, the characteristic melting point is the melting temperature of that metal or alloy. The characteristic melting point should preferably be low enough so that the integrated circuit and the first and second substrates are not damaged during the heating. Typically, the characteristic melting point is less than 300 °C, and preferably less than 200 °C, for example in the range from 100 °C to 200 °C.

The antenna terminals contact can be made of an alloy comprising tin and bismuth. Such materials can be melted and cured quickly and often have characteristic melting points that are particularly suitable for the present invenﬁon. ln accordance with one embodiment, the other parts of the antenna elements are also made of a material having a melting point at or below said characteristic melting point. For example, the antenna elements can also be made of an alloy comprising tin and bismuth. Hereby, the soldering together of the antenna terminals and the antenna contacts becomes even quicker and easier.

Thus, the heating of the conductive material to a temperature exceeding a characteristic melting temperature of the conductive material results in a melting and solidification of the conductive material. This may in itself be sufficient to form the contact. However, the method may also comprise a step of applying a pressure onto the heated conductive material.

This pressure is preferably applied relatively soon after the heating, so that the material still remains in a melted or almost melted state. Hereby, a good adhesion and good continuity of conductivity will be ensured.

It should be noted that the entire contact terminal(s) is not necessarily heated to a temperature at least equal to the characteristic melting point. lt may be that only a portion of the contact terminal(s) is heated to such a temperature.

The present invention is based on the realization that dual-sided integrated circuits (lCs) including antenna contacts arranged on opposite surfaces allow connection to antenna elements in a very fast and reliable way, and with significantly reduced need for placement accuracy. This also enables use of very small sized lCs, and with significantly lower need for antenna gap resolution. It has further been found that this type of lCs is surprisingly well suited for production and assembling with a heat-induced attachment process. This process can e.g. be a sheet-to-sheet process, but may also be performed as a roll-to-roll process. This makes production very fast, and dramatically increases the throughput. At the same time, the assembly machine can be made simpler and less costly. Overall, this enables production of very small RFID tags and labels to a very low cost.

A factor that contributes to the speed and simplicity of the method is that the step of operatively connecting the antenna elements to the IC can be performed with relatively low precision, acceptable tolerances typically being in the range of 10.5 mm. By comparison, mounting the IC to the antenna in a conventional way must usually be done with very high precision, typically with tolerance requirements of about +/- 50 microns.

The method is easy to integrate with many existing productions lines, especially production lines for producing packaging products because of the equipment typically used in such production lines. Further, since the RFID lCs may now be connected to the antenna elements close to and just before application of labels/tags to e.g. a package, or in the formation of a product, the package or product producer obtains greater control of the process. Thus, the method and apparatus of the present invention can e.g. be arranged as an integral part of a packing line, converting line or even into die cutting units.

The production of the antenna elements also becomes faster, simpler and less costly, since relatively large and coarse antenna terminals may be used. The antenna elements can also be produced directly on e.g. a packaging material, whereby no extra layers and the like is needed, in contrast to in current label-based delivery formats.

The connecting of the lCs to the antenna elements in this way is also very fast. A connection in the time scale of ms can be achieved, such as in the range of <1 s, and in particular in the range 1-500 ms, whereas currently used boding times are typically in the range 7-9 s.

The mounting and connection of the lCs to the antenna elements is also made without e.g. the need to flip the lC:s, as in currently used flip-chip processes, and there is no need for thermo-compression curing and the like.

The first substrate area may be provided on a first substrate, and the second substrate area may be provided on a separate second substrate. However, alternatively, the first and second substrate areas may be provided on the same substrate, wherein the substrate may be folded to bring the first substrate area and the second substrate area together.

The one or more substrate(s) may be provided in the forms of sheets and/or webs, and may e.g. be provided in the form of a roll of substrate web.

The method may e.g. be a roll-to roll process, in which input rolls are provided at one end and output rolls are received at the other. Hereby, the process is highly suitable for fully automated production. ln such a process, the method/apparatus also preferably comprises re-winding of the assembled web on an output roll, at a re-winding station.

The roll-to-roll process is highly suitable for production of RFID transponders arranged on a carrying substrate forming RFID labels or RFID tags.

Alternatively, the substrate(s) may form a packaging material, and wherein the RFID transponders arranged on a carrying substrate forms a packaging blank for an intelligent packaging product. This can also be made in a roll-to-roll process, but may alternatively be made in a sheet-to-sheet process or in a roll-to-sheet process. Thus, for production of intelligent packaging products, the antenna elements may be provided directly on a package material, in the form of a sheet or a web, and the lCs may be connected to the antenna elements e.g. in a packaging converting facility. Hereby, packaging blanks for use as intelligent packages, and with integrated RFID transponders, can be produced in a very efficient way.

The heating may be applied be means of a contactless heating technique. Using such a technique helps to reduce the risk of the antenna element and/or the contact pads becoming smeared out. Also, such techniques typically allow for the heating step to be performed with relatively low precision, thus helping to make this step simple and fast.

The method may comprise pressing the heated antenna elements, and in particular the antenna terminals, and the corresponding antenna contacts against each other. This may further strengthen the mechanical connection between the antenna element and the contacts. The antenna terminals may be pressed against the corresponding antenna contacts simultaneously with the heating, and/or after the heating. The pressure may be applied by a nip. ln case heating and pressing should occur simultaneously, the nip may have a surface temperature at or above the characteristic melting point. lf pressure is applied after heating, as a separate step, the surface temperature of the nip is preferably lower than the characteristic melting point.

An adhesive may be arranged on at least one of the first and second substrate areas, the adhesive being arranged to adhere the first and second substrate areas together after the first and second substrate areas have been brought in mechanical contact. The adhesive helps to create a strong attachment between the first and second substrate areas. The adhesive may also act as dielectric material between the conductor pattern/antenna element below the IC and conductor pattern/antenna element above the IC, and will consequently also serve the purpose of preventing short-circuiting of those antenna elements/conductor patterns. A lamination nip may also be used to apply pressure onto the assembled substrate, to provide an even better lamination.

The one or more substrate(s) can be made of at least one of: paper, board, polymer film, textile and non-woven material. ln particular, the substrate(s) can be made of paper. Thereby, the RFID transponders become particularly suitable for attachment to objects made of paper materials, such as boxes for packaging.

The RFID transponders may be either passive, i.e. powered by a reader's electromagnetic field, or active, i.e. powered by an onboard battery.

The antenna elements may be produced in various ways. For example, the forming of the conductive pattern can be made by printing with conductive ink, such as silver ink, i.e. ink comprising conductive silver particles, or particles of carbon, copper, graphene, etc. The ink may also comprise two or more different materials, such as particles of different materials, or particles comprising two or more materials. ln particular, the ink may comprise a material having a characteristic melting point being similar, identical or below the characteristic melting point of the contact pads. The solvent can be evaporated by means of heating at an elevated temperature, by use of photonic curing, or the like. The forming of the conductive pattern can also be made by first providing a conductive layer on the substrate, and the removing or forming this conductive layer into the desired conductive pattern, e.g. by means of grinding, cutting, or the like. This can e.g. be made in the way disclosed in EP 1 665 912 and WO 2005/027599, said documents hereby being incorporated in their entirety by reference. ln order for such antenna elements to connect to the IC during heating, it is preferred that at least the ink used to form the antenna terminals is thermoplastic, and has a relatively low characteristic melting point, such as below 300 deg. C, to reduce the risk of damage to the lC:s due to the heat. ln one embodiment, the forming of conductive material in a pattern comprise: transferring a conductive material in a pattern corresponding to said electrically conductive pattern to a surface of the substrate; and heating the conductive material to a temperature exceeding a characteristic melting temperature of the conductive material.

The conductive material is preferably in the form of electrically conductive solid particles. The transferring of conductive material to the substrate surface may e.g. comprise direct printing of electrically conductive particles as a part of a compound that contains, in addition of the electrically conductive solid particles, a fluid or gelatinous substance. However, the electrically conductive solid particles may also be in the form of dry powder. Further, an adhesive area may be created on the surface of the substrate prior to transfer of the particles.

The transfer of the conductive particles and the curing and solidification may in particular be made in the way disclosed in one or several of WO 2013/113995, WO 2009/135985, WO 2008/006941 and WO 2016/189446, all of said documents hereby being incorporated in their entirety by reference.

Curing may be effected by heating, or by a combination of heat and pressure. ln case both heat and pressure are used, the curing may be referred to as sintering. During curing, the transferred conductive material, e.g. in the form of particles, is converted into a continuously conducting pattern affixed to the web substrate. The sintering is preferably carried out in a nip comprising two opposing nip members, at least one of which may be heatable, between which the web is fed. Additionally, or alternatively, the curing may also comprise irradiation of the conductive material, e.g. with UV radiation, e-beam radiation or the like.

The two antenna elements arranged on the two substrate areas may be identical or symmetrical to each other. Preferably, the two antenna elements have essentially the same size and coverage area. However, alternatively, one of the antenna elements is larger than the other. The two antenna elements, when electrically connected to the IC, together form an antenna for the RFID transponder, wherein the first antenna element forms X% of the antenna and the second antenna element forms 100-X% of the antenna, where X > 0. X may here be 50, whereby the two antenna elements have the same size, but X may also be any number between 1-and 99, such as between 25 and The dual-sided ICs can e.g. be made and designed in accordance with the disclosures of US 9489611 and US 2014/0144992, said documents hereby incorporated in their entirety by reference. The internal wirings of the microchip are designed so that the IC has one antenna contact at one side, and another antenna contact at the other.

The antenna contacts on the IC are preferably relatively large, in terms of the size of the IC. For example, at least one of the first antenna contact and the second antenna contact may include a conductive pad spanning substantially an entirety of the first external surface or the second external surface of the IC, respectively. However, a bump of smaller length and width dimensions may also be used, on one or both sides of the IC. Thus, the IC can be provided with a bump on each of the two opposing sides, or with a pad on each of the two opposing sides, or with a bump on one side and a pad on the other. The bumps/pads could be made of any commonly used material, such as gold, aluminum or copper.

The invention is inter alia based on the surprising realization of the present inventors that a label converting process is in many aspects similar to methods for producing printed electronics. Thus, by means of the present invention, an electrically conductive pattern, forming the antenna elements for the RFID transponder, can be formed as an integral part of a conventional label converting process. This enables the production of labels with integrated electrically conductive patterns in a much faster and more cost-efficient way. lt also enables enhanced control of the entire process, since it is all made at once, and in a single production line. There is therefore no longer a need to form the electrically conductive patterns separately, and also no need for the difficult and cumbersome process of connecting the electrically conductive patterns onto already produced labels. The same process may also comprise, as an integrated step, the arrangement and connection of the integrated circuit, i.e. the RFID chip. Hereby, many steps that are conventionally performed separately in each of these processes, such as insertion of web rolls, threading of webs through the production path, re-winding, etc, can hereby be performed only once, which makes the process much more cost and time efficient. lt also reduces the overall need for manufacturing machinery and production space.

According to another aspect of the invention, there is provided an apparatus for producing a radio-frequency identification transponder on a carrying substrate, comprising: an input station to receive one or more substrate, the substrate(s) having a first substrate area and a second substrate area, the first and second substrate areas each having at least one antenna element formed byan electrically conductive pattern arranged thereon, and preferably several antenna elements arranged sequentially thereon along a longitudinal extension of the first and second substrate areas, wherein a first antenna element arranged on the first substrate area has a first antenna terminal, and a second antenna element arranged on the second substrate area has a second antenna terminal; a placement device arranged to place a dual-sided integrated circuit (IC) on the first substrate area, the IC including a first circuit block electrically coupled to a first antenna contact, disposed on a first external surface of the IC, and a second antenna contact, disposed on a second external surface of the IC opposite the first external surface of the IC, and wherein the IC is placed on the first substrate area in such a way that the first antenna contact comes in mechanical contact with the first antenna terminal; a transfer device configured to bring the first substrate area and the second substrate area together, thereby bringing the second antenna contact in mechanical contact with the second antenna terminal; a heating device configured to heat the first and second substrate areas in the vicinity of the IC to a temperature at least equal to a characteristic melting point of said first and second antenna terminals, thereby forming electric contact between the first antenna contact and the first antenna terminal, and between the second antenna contact and the second antenna terminal.

By this aspect of the invention, similar advantages and preferred features and embodiments as discussed above, in relation to the first aspect of the invention, are obtainable.

The apparatus may be realized based on a conventional label converting machine, but with added equipment and stations to form the electrically conductive pattern, and for connecting an integrated circuit, such as an RFID chip, to the electrically conductive pattern.

As discussed above, the forming of the conductive pattern can be made in various ways. According to one embodiment, the pattern forming station comprises a particle handler for transferring a conductive material in a pattern corresponding to the electrically conductive pattern to a surface of theface material web; and a heater for heating the conductive material to a temperature exceeding a characteristic melting temperature of the conductive material.

The apparatus may further comprise a pressing device arranged to press the first and second substrate areas against each other over the IC. The pressure may e.g. be applied by a nip, wherein the surface temperature of the nip may be lower than said characteristic melting point.

The apparatus may further comprise an adhesive applicator, arranged to provide an adhesive on at least one of the first and second substrate areas, the adhesive being arranged to adhere the first and second substrate areas together after the first and second substrate areas have been brought in mechanical contact.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

Brief description of the drawinqs For exemplifying purposes, the invention will be described in closer detail in the following with reference to embodiments thereof illustrated in the attached drawings, wherein: Fig 1 is a schematic illustration of a production line for producing RFID labels or RFID tags in accordance a method and apparatus of an embodiment of the present invention; Fig 2 is a schematic illustration of a production line for producing RFID labels or RFID tags in accordance with another embodiment of the present invention; Fig 3 is a schematic illustration of a production line for producing RFID labels or RFID tags in accordance with still another embodiment of the present invention; Fig 4a-c are schematic illustrations of RFID transponders producible by the present invention, where Fig 4a illustrate top views of two substrate webs provided with complementary antenna elements, Fig 4b illustrate a top view of the antenna elements of Fig 4a assembled together with lC:s, where thesubstrate webs are shown as fully transparent, and Fig 4c is a side view of one of the transponders in Fig 4b; Fig 5 is a schematic illustration of a substrate web provided with two complementary antenna elements, intended to be folded over each other to form the antenna; Fig 6 is a schematic illustration of second embodiment of a foldable substrate web; Fig 7 is a schematic illustration of third embodiment of a foldable substrate web; Fig 8 is a schematic illustration of fourth embodiment of a foldable substrate web; and Fig. 9a and b are schematic illustrations of a production line for producing RFID labels or RFID tags in accordance with yet another embodiment of the present invention.

Detailed description of preferred embodiments ln the following detailed description preferred embodiments of the invention will be described. However, it is to be understood that features of the different embodiments are exchangeable between the embodiments and may be combined in different ways, unless anything else is specifically indicated. It may also be noted that, for the sake of clarity, the dimensions of certain components illustrated in the drawings may differ from the corresponding dimensions in real-life implementations of the invention, such as the thickness of various layers, etc. Further, the invention will in the following primarily be exemplified in relation to a roll-to-roll process, where the substrates are provided in the form of webs arranged on rolls. However, it is to be appreciated by the skilled reader, that the process may also be used for substrates of other types, such as sheets. Thus, the process may also be embodied as a sheet-to-sheet process or a roll-to-sheet process.

With reference to Fig 1, a production method and apparatus for forming RFID transponders, such as RFID labels or tags, will now be discussed in more detail.The system 100 comprises a first input or unwind station 101a, provided with a reel holder for receiving rolls 102a of a substrate web 200a. The substrate web can e.g. be paper.

The substrate material is preferably a fibrous web, and can be of any of a wide variety of materials, widths and thicknesses. Paper and polymer films (plastics) are suitable, but other similar non-conductive surfaces may be also used. The substrate material may also be coated, and a multilayered web may also be used.

The substrate web is transferred to a particle handler 103a, arranged to transfer a conductive material in a pattern onto a surface of the substrate web. The pattern corresponds to the electrically conductive pattern of one of the antenna elements to be provided in the RFID transponder.

Prior to the particle transfer, an adhesion area may be formed in the surface of the web, as is per se known in the art, in order to maintain the particles in the desired place until melting and pressing has occurred. However, depending on the materials used, etc, this step may also be omitted. The adhesion area may be formed in correspondence with the intended pattern for the electrically conductive pattern to be formed, and may e.g. be formed by dispersive adhesion (i.e. gluing) or electrostatic adhesion. This may e.g. be performed by an adhesive printing or lacquering section (not separately shown) that is configured to spread an adhesive or lacquer onto the substrate to create an adhesion area of predetermined form, or by an electric charger section that is configured to create a spatial distribution of static electric charge in the web material to create an adhesion area of predetermined form. However, additionally or alternatively, the particles may directly be transferred onto the web in correspondence with the electrically conductive pattern to be formed. lt is also possible to transfer electrically conductive solid particles onto the surface of the substrate with a method that involves simultaneously creating the necessary adhesion. For example, the electrically conductive solid particles may come as a part of a compound that contains, in addition to the electrically conductive solid particles, a fluid or gelatinous substance that has adhesive properties. ln that case, the preparatory creation of adhesion areas may be omitted.

The conductive material is then cured to form a solidified, more compact pattern. This can e.g. be made by application of heat with a heater 104a. Hereby, the conductive material is preferably heated to a temperature exceeding a characteristic melting temperature of the conductive material.

The heating is preferably a non-contacting heating, which reduces the risk of smearing or unwanted macroscopic changes in the spatial distribution of conductive material on the surface of the web. However, heating methods that are contacting may also be used. Especially if heating is made with low or very low contact pressure, it may well have the same advantageous non- smearing characteristics. As a result of the heating, a melt is created.

Non-contacting heating may e.g. be obtained by infrared radiation, laser heating, or heating with other types of radiation, inductive heating, streaming with hot gas, etc. However, heating may also be made by bringing the substrate web or the conductive material into contact with a heated body, such as a heated nip.

The heating of the conductive material to a temperature exceeding a characteristic melting temperature of the conductive material results in a melting and solidification of the conductive material. This may in itself be sufficient to form the electrically conductive pattern, in particular if the heating also involves contacting the transferred particles with pressure.

However, the method may also comprise a step of applying a pressure onto the heated conductive material, subsequent to the heating but prior to lamination. This pressure may be applied by a nip (not shown), and preferably the surface temperature of the nip is lower than the characteristic melting temperature. This pressure is preferably applied relatively soon after the heating, so that the material still remains in a melted or almost melted state. Hereby, the pressure will cause the previously melted material to solidify in the form of an essentially continuous, electrically conductive layer that covers an area on the face material web corresponding to the intended electrically conductive pattern.The nip may be a non-heated nip. However, preferably, the nip is heated to a temperature only somewhat lower than the characteristic melting temperature, such as 30-60 degrees C lower. This ensures for example that the melt will not solidify prematurely, before it would become pressed against the substrate. The nip will cause the previously molten material of the originally solid electrically conductive particles to solidify again, but this time not in the form of separate particles but in the form of an essentially continuous, electrically conductive layer, arranged in the predetermined pattern.

However, in other embodiments, the nip temperature may be equal or almost equal to the characteristic melting temperature of the used electrically conductive material.

Further, as already discussed, the pressing step may in some embodiments be omitted. Still further, other nips used in the process, e.g. the lamination nip discussed in more detail below, may be arranged to provide a pressure sufficient also for solidifying the melted particles, even without any additional pressing step prior to lamination.

The electrically conductive solid particles may be of any metal, and may e.g. be of pure metal. However, the particles are preferably formed of alloys, and most preferably non-eutectic alloys. ln particular, it is preferred to use particles of metallic compounds that are - or resemble - so-called low temperature solders. The alloys preferably comprise tin and bismuth.

A non-limiting example list of such metallic compounds includes (indicated percentages are weight percentages): o tin /silver (3.43 percent) /copper (0.83 percent) o tin / silver (2-2.5 percent) /copper (0.8 percent) / antimony (0.5- 0.6 percent) o tin / silver (3.5 percent) / bismuth (3.0 percent) o tin /zink (10 percent)o tin / bismuth (35-58 percent) o tin / indium (52 percent) o bismuth (53-76 percent) / tin (22-35 percent) / indium (2-12 percent) o tin (35-95 percent) / bismuth (5-65 percent) / indium (0-12 percent).

At room pressure, the first four listed examples melt between 180 and 220 degrees centigrade, while the four Iast-mentioned may melt at significantly lower temperatures, even below 100 degrees centigrade.

Preferably, the particle-type conductive matter consists essentially of metal or metal alloy particles. The metal or metal alloy preferably has an atmospheric-pressure characteristic melting temperature of less than 300 degrees C, and more preferably less than 250 degrees C, and most preferably less than 200 degrees C, such as in the range 50-250 deg. C, or preferably within the range 100-200 deg. C, which makes the method suitable, for example, for conventional paper, the physical properties of which may permanently change at too high temperatures. Suitable metals include, e.g. tin, bismuth, indium, zinc, nickel, or similar, used as single metals or in combinations. For example, tin-bismuth, tin-bismuth-zinc, tin-bismuth-indium or tin-bismuth-zinc-indium in different ratios may be used. ln tin-containing alloys, the ratio of tin in the alloy is preferably 20 - 90 wt- percent, and most preferably 30 - 70, wt- percent of the total weight of the components in the alloy.

One possible embodiment for transferring the conductive material to the substrate web has been discussed in detail above. However, other ways of obtaining this conductive material transfer are also feasible. The material transfer may e.g. be obtained by: - Transfer roll having electrodes, which are in different potential than the particle deposited on the surface of the transfer roll.

- Electro-photographic transfer, where the particles may be deposited in a solvent. The solvent is evaporated or absorbed by the substrate (in particular paper or board), where after the sintering is carried out for (almost) dry particles.- Screen printing, where particles in liquid form (i.e. where particles are arranged in solvent or suspension) are transferred to the substrate through a web-like screen means (cloth or metal) or through a stencil.

- Gravure printing, flexographic printing, offset printing, ink-jet printing or the like of particles dissolved or suspended in carrier medium.

Further, other ways of forming the conductive material in a pattern can also be used. For example, the forming of the conductive pattern can be made by printing with silver ink, i.e. ink comprising conductive silver particles. The solvent can then be evaporated by means of heating at an elevated temperature, by use of photonic curing, or the like. The forming of the conductive pattern can also be made by first providing a conductive layer on the web, and the removing or forming this conductive layer into the desired conductive pattern, e.g. by means of grinding, cutting, or the like.

At a second input or unwind station 101b, a second roll 102b ofa second substrate web 200b is provided on a second reel holder. The second substrate web may e.g. be a paper material, and may e.g. be the same material as in the first substrate web 200a. However, it is also possible to use different material in the two substrates. The second substrate web can be of any width and thickness. However, the width preferably corresponds to the width of the first substrate web.

The second substrate web is also provided with electrically conducting pattern, to form second antenna elements to be provided in the RFID transponder. To this end, there is, similar to the discussion above in relation to the first web, provided a particle handler 103b, arranged to transfer a conductive material in a pattern onto a surface of the substrate web.

The conductive material is then cured to form a solidified, more compact pattern. This can e.g. be made by application of heat with a heater 104b. Hereby, the conductive material is preferably heated to a temperature exceeding a characteristic melting temperature of the conductive material. The forming of the second antenna elements can be made in the same way as for the first antenna elements, or alternatively be varied and different in accordance with the discussion above.The first antenna elements and the second antenna elements are complementary to each other, and thereby together, when combined, form the entire antenna of the RFID transponder. Each antenna is further provided with an antenna terminal, to be electrically connected to a corresponding antenna contact of an IC. This will be discussed in more detail in the following.

When the antenna elements have been provided on the first substrate web, the first substrate web continues to an adhesive applicator 105, providing a layer of adhesive on a surface of the substrate web. The adhesive may e.g. be a pressure sensitive adhesive (PSA) or a pressure sensitive hot melt adhesive. Further, the adhesive is preferably a non-conductive adhesive, such as a non-conductive paste (NCP), or an anisotropic conductive paste (ACP). The adhesive/paste is preferably arranged for thermal compression bonding. The adhesive is preferably applied in liquid form, and cured/solidified when heated. However, acrylic adhesive,, hot-melt adhesive or any other suitable adhesive may also be used. The adhesive can, additionally or alternatively, be provided after placement of the IC.

Thereafter, the first substrate is brought to a transfer device 106 arranged to place IC:s at suitable positions on the first substrate. The IC:s are dual-sided lC:s, each having a circuit block electrically coupled to a first antenna contact, disposed on a first external surface, and a second antenna contact, disposed on second, opposite external surface of the IC. The IC:s may e.g. be of any of the types disclosed in US 9489611 and US 2014/0144992, said documents hereby incorporated in their entirety by reference.

The IC:s are placed over the antenna elements of the first substrate web, and more particularly so that the first antenna contacts of the IC:s come in mechanical contact with the first antenna terminals of the first antenna elements.

The transfer device may comprise a pick-and-place equipment or the like, picking the IC:s from a storage supply, such as a stack, a container, a batch hopper, a wafer or the like, and placing the IC:s at the intended position on the first substrate web. The picking tool may e.g. operate by vacuum. However, due to the relatively large tolerances allowed, the placement of the lC:s on the first web can also be obtained in simpler ways. For example, the lC:s may simply be dropped onto the first substrate web from a short height, and at controlled times.

Due to the high tolerances, placement of the lC:s can be made while the web is moving. However, if there is need for higher precision, the web may alternatively be brought to intermittent quick halts during the placement.

The two webs, the first substrate web with the first antenna elements and the lC:s placed in contact with the first antenna elements, and the adhesive, and the second substrate web with the second antenna elements are then brought together, and laminated in a lamination nip 109. The webs are brought together so that the second antenna contact of the lC:s, arranged on the opposite side of the lC:s, and facing away from the first substrate web, towards the second substrate web, are brought into contact with the second antenna terminals, provided on the second antenna elements. The lamination nip 109 exerts a pressure towards the webs, thereby effecting lamination. However, the lamination nip may also optionally be a heated nip, thereby also effecting lamination by additional heating.

The substrates are further heated to a temperature exceeding the characteristic melting point of the material forming the antenna elements, and in particular at the areas corresponding to the first and second antenna terminals. The heat can be applied by the nip 109. However, additionally or alternatively, heat can be provided upstream or downstream from the lamination nip 109. The heating of the antenna terminals makes the material solder into contact with the antenna contacts of the IC, thereby forming an electrical contact between the first antenna contact and the first antenna terminal, and between the second antenna contact and the second antenna terminal, respectively.

After lamination, a die cutter 110 or the like may be provided in order to separate the labels/tags from each other, and to provide the desired shape and dimensions of the labels/tags. The die cutting station may e.g. be used to perforate the web, or completely cut through the web material along cuttinglines. The die cutting station is preferably held in registration with the insertion stations so that the Iaminated label web may be cut without cutting through an electrically conductive pattern. The die cutting station may comprise cutting elements, e.g. in the form of one or more rotary die or other types of tooling for cutting or perforating used for forming labels or tags. The die cutting station may also comprise a monitor or sensor to identify the location of the electrically conductive pattern, to ensure that cutting does not occur over the electrically conductive patterns.

Further, a waste matrix removal station 110 may be provided, and the removed matrix may be rolled onto a waste roll The finished, Iaminated web may then be re-winded onto a third roll 113 at a re-winding station The labels may also be provided with an additional layer of adhesive on an outer surface, useable to adhere the label to packages, containers and the like. ln that case, the labels may further comprise an easily removable release liner to cover the adhesive.

The labels may further comprise printed information, in the form of text, digits, bar codes, etc. To this end, the system may further comprise a printing station, e.g. for printing the first substrate web. The printing station (not shown) can e.g. be arrange prior to the particle handler 103. However, the roll 102 of substrate web may also comprise pre-printed label stock. The printing can be made by flexographic printing, off-set printing or any other printing method.

The re-winding station 113 may also comprise post-processing means that are configured to post-process the final web, for example by cooling, removing static electric charge, coating, evaporation of volatile components of substances present within or on the web, or the like.

One or more tensioning devices (not shown) may also be provided along the production line, to control the tension of the webs, as is per se known in the art. ln the above-discussed method and apparatus, the complete RFID transponders are formed within a single process, including formation of the antenna elements, placement of the lC:s and connecting the lC:s to theantenna elements. However, alternatively, the antenna elements may be provided on the substrate webs in a separate procedure, and the rolls of substrate webs already containing the antenna elements may be used as input material for a process in which the lC:s are brought into place and the webs are laminated. Such an embodiment is illustrated in Fig.

Additionally, a programming and/or testing station may be provided. At the programming and/or testing station, the RFID transponders may be programmed, in case they are not preprogrammed before placement on the labels, and the function of each RFID transponder may be tested and verified. The programming and/or testing station may comprise an interrogator system comprising an RFID antenna or multiple antenna arrays for checking and testing the functionality of each RFID transponder. More specifically, the station may comprise an RFID reader or an RFID reader/writer. ln the process of Fig. 2, rolls 102a' and 102b' of substrate webs already having antenna elements are provided at a first and second input or unwind stations 101a' and 101b', provided with reel holders. The antenna elements on these substrates may e.g. be produced in the same way as discussed above in relation to the first embodiment.

One of the substrate webs then passes an adhesive applicator 105, and an IC placement device 106, in the same way as discussed above. The two webs are then brought together, to form contact between the antenna elements and the lC:s, and heat and pressure is applied by the lamination nip 109, and the final web is assembled on an output roll Pre-forming of the antenna elements on the substrate webs, as in the Fig 2 embodiment, is particularly advantageous if the same type of antenna elements is used on the two webs. ln this case, the two substrate webs can be formed in the same process, and using the same production equipment.

Similar to the first embodiment, the lamination and the forming of the electric contact to the IC can be made by hot nips. However, it is also possible to use multiple hot nips, a pre-heater unit in combination with a cold nip, etc. ln an alternative solution, as illustrated in Fig 3, the heating is provided by a hot roller 109' with defined web tension. The web tension hereby pressesthe IC antenna contacts and the antenna terminals together, and this, in combination with the heating, makes appropriate bonding to occur. Such bonding can be done at very high speed, since only a short time (typically less than 1 s) is needed.

The electrical connection between the antenna contacts and the antenna terminals are, as discussed previously, formed by the heat and optional pressure applied, thereby soldering the antenna terminals onto the antenna contacts. However, in particular if relatively large antenna contacts, such as pads extending over a substantial part of the IC surface, are used, the need for heat and pressure is lowered, since the electric contact may also be formed by capacitive coupling between the antenna contact and the antenna terminal. ln particular, it may be advantageous to use such relatively large antenna contacts, e.g. in the form of pads, at the antenna contact arranged towards the substrate web on which the IC is first placed. Hereby, the electrical connection becomes less sensitive to disturbances caused by the adhesive and the like.

The connection of the antenna elements and the IC:s will now be discussed in more detail, with reference to the embodiment illustrated in Fig. 4 a-c. ln Fig. 4, the first and second substrate webs 200a and 200b are illustrated. Each comprises a plurality of antenna elements 201a, 201 b. The antenna elements form part of a dipole antenna, and each terminates in an antenna terminal 204a, 204b. The antenna elements are producible in the ways discussed in the foregoing, and the antenna elements may take many different shapes and dimensions, as will be discussed in further detail in the following.

An IC is placed over each antenna terminal 204a on the first substrate web 200a, and the second substrate web 200b is then laminated over the first substrate web, as discussed above. Hereby, the antenna terminals 204a and 204b are connected to the antenna contacts 203a, 203b arranged on each side of the IC, thereby together forming an antenna for the RFID transponder. This is illustrated in Fig 4b and Fig 4c.ln the previously discussed embodiments, the first antenna elements are provided on a first substrate, and the second antenna elements are provided on a second substrate, being separate from the first substrate. However, it is also possible to provide the first antenna elements on a first substrate area on a substrate, and to provide the second antenna elements on a second substrate area on the same substrate. After placement of the lC:s on the antenna terminals on the antenna elements on the first substrate area, the substrate is folded, so that the second substrate area is placed over the lC:s in the intended position, to be laminated and electrically connected.

Thus, the production apparatus for such an embodiment may be realized in a similar way as in the previously discussed embodiments, but with only one input substrate web.

Such a substrate web, to be used in a folding substrate, is illustrated in Fig. 5. ln this embodiment, the same type of antenna elements as discussed in relation to Fig. 4 are used. However, in this embodiment, a single substrate web is provided, comprising a first substrate area 200a' and a second substrate area 200b'. The first and second substrate areas are separated by a folding line 205. The first antenna elements 201a are provided on the first substrate area 200a', and the second antenna elements 201 b are provided on the second substrate area 200b'.

After placement of the lC:s on the antenna elements on the first surface area 200a', the substrate is folded, in a folding station, so that the second surface area 200b' comes into contact with the lC:s. The antenna elements are then heated to laminate the surface areas together, and to form the electrical contact between the antenna terminals and the antenna contacts in the same way as in previously discussed embodiments.

The antenna elements may be designed and dimensioned in many different ways. ln the previously discussed embodiment, the antenna elements are extending symmetrically outwards from a centrally arranged IC. ln another embodiment, as illustrated in Fig. 6, the antenna elements 201a' and 201 b' are arranged in a side-by-side arrangement, with the antenna terminals provided on the same side of the antenna, and both the antenna terminals extending in the same direction in relation to IC 202. ln the illustrative example, the antenna elements are arranged on a single substrate, foldable along a folding line 205, but the same principle may be used in a two substrate embodiment. ln the embodiment of Figs. 5 and 6, the antenna elements extend in a direction along the width direction of the substrate. However, the antenna element may also extend along the longitudinal direction of the substrate, as illustrated in Fig. 7, where the antenna elements 201a" and 201b" extend in the length direction of the substrates, and are foldable over each other. Again, the same principle may be used in a two substrate embodiment. ln the above-discussed embodiments, the substrate is provided in a roll, to be used in a roll-to-roll process or a roll-to-sheet process. However, the input substrate(s) may also be provided in the form of sheets. The sheets may e.g. be die-cut blanks for packages.

The previously discussed antennas, having antenna elements of essentially the same size, and being symmetrical to each other, are in particular suited for use at rather high frequencies, such as the UHF (Ultra High Frequency) band, e.g. in the range 800-1000 MHz.

However, the first and second antenna elements may also be differently sized and shaped. Thus, the first antenna element may form X% of the antenna, whereas the second antenna element forms 100-X% of the antenna, where X is any number between 1 and 99. Such antennas are for example well suited for lower frequencies, such as antennas for use in the HF (High Frequency) band, e.g. at 13.6 MHz.

One such asymmetric embodiment is illustrated in Fig. 8. Here, one of the antenna elements 201a"', to be arranged on either the first or the second substrate or substrate areas, is shaped as a helix. The helix may have circular coils, but other shapes, such as hexagonal, octagonal, rectangular, triangular, and similar, may also be contemplated. ln the illustrative example, a rectangular helix is provided. The helix extends in widening coils from an inner first antenna terminal 204a"'. The second antenna element 201 b"' is here in the form of a bridge, connecting the outer end of the helix to a second antenna terminal 204b"'.ln this embodiment, a foldable substrate is used, and the bridge is connected to the helix, and extends into the other substrate area, crossing a folding line The IC is placed on either the first or the second antenna terminal, and the substrate is then folded so that the IC also comes into contact with the other antenna terminal. ln this embodiment, the heating and optional pressing may occur locally, only to create an electrical contact between the antenna contact of the IC and the antenna terminals, and to avoid short circuiting between the helix and the strap. However, in order to further avoid such short circuiting, the adhesive may in this embodiment be of a kind providing a dielectric layer between the HF antenna helix and the bridge. The bridge pattern may also have adhesive coating of the area that needs to be electrically insulated from the helix pattern. ln this embodiment, the lamination is preferably made with no or relatively low heating, such as by using a cold nip.

However, the bridge may also, alternatively, be provided on a separate substrate, as illustrated schematically in Fig. 8. Fig. 8a illustrates the two substrate webs, a first substrate web 200a being provided with a helix antenna pattern 201a"", and a second substrate web 200b being provided with a bridge antenna pattern 201 Again, an adhesive providing dielectric properties may be used to avoid short circuiting.

After placement of an IC between the antenna terminals, a local heating may be applied, connecting the ends of the bridge to the IC antenna contact at one end, and to the outer end of the helix at the other end. This may e.g. be accomplished by a fork-like heating element 109', as illustrated in Fig 8b. ln this embodiment, depending on the adhesive used, there may be no need for a nip or any application of pressure.

Specific embodiments of the invention have now been described. However, several alternatives are possible, as would be apparent for someone skilled in the art. For example, various ways of providing the transfer and curing of the conductive material for obtaining the electrically conductive pattern is feasible. Further, the electrically conductive pattern may function as different types of antennas, and not only dipole antennas. Further,lamination may be obtained by use of a pressure sensitive adhesive, and application of a pressure to the webs to be Iaminated, but other ways of laminating the webs are also feasible. Further, placement and attachment of the integrated circuit to the electrically conductive pattern can be provided as integrated steps in the process of forming the labels, but may alternatively be provided in a separate process. Such and other obvious modifications must be considered to be within the scope of the present invention, as it is defined by the appended claims. lt should be noted that the above-mentioned embodiments i||ustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. ln the claims, any reference signs placed between parentheses shall not be construed as limiting to the claim. The word "comprising" does not exclude the presence of other elements or steps than those listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. Further, a single unit may perform the functions of several means recited in the claims.

Claims

1. A method for producing radio-frequency identification (RFID) transponders arranged on a carrying substrate, comprising: providing a first substrate area (200a; 200a') and a second substrate area (200b; 200b'), the first and second substrate areas each having at least one antenna element formed by an electrically conductive pattern arranged thereon, and preferably several antenna elements arranged sequentially thereon along a longitudinal extension of the first and second substrate areas, wherein a first antenna element (201a; 201a'; 201a”; 201a'”, 201B””) arranged on the first substrate area (200a; 200a') has a first antenna terminal (204a; 204a”'), and a second antenna element (201 b; 201 b'; 201b”; 201b”'; 201b””) arranged on the second substrate area (200b; 200b') has a second antenna terminal (204b; 204b”'); providing a dual-sided integrated circuit (IC) (202) including a first circuit block electrically coupled to a first antenna contact (203a), disposed on a first external surface of the IC, and a second antenna contact (203b), disposed on a second external surface of the IC opposite the first external surface of the IC; arranging the IC on the first substrate area (200a; 200a'), whereby the first antenna contact (203a) comes in mechanical contact with the first antenna terminal (204a; 204a”'); bringing the first substrate area (200a; 200a') and the second substrate area (200b; 200b') together, thereby bringing the second antenna contact (203b) in mechanical contact with the second antenna terminal (204b; 204b”y heating the first and second substrate areas in the vicinity of the IC (202) to a temperature at least equal to a characteristic melting point of said first and second antenna terminals, thereby forming electric contact between the first antenna contact (203a) and the first antenna terminal (204a; 204a”'), and between the second antenna contact (203b) and the second antenna terminal (204b; 204b”').

2. The method of claim 1, wherein said heating is provided using a contactless heating technique.

3. The method of claim 1 or 2, further comprising pressing the first and second substrate areas against each other over the IC (202), during or after said heating.

4. The method of any one of the preceding claims, wherein an adhesive is arranged on at least one of the first and second substrate areas, the adhesive being arranged to adhere the first and second substrate areas together after the first and second substrates have been brought together.

5. The method of any one of the preceding claims, wherein at least one of the first and second substrate areas are made of at least one of: paper, board, polymer film, textile and non-woven material.

6. The method of any one of the preceding claims, wherein the first and second antenna terminals are made of an alloy comprising tin and bismuth.

7. The method of any one of the preceding claims, wherein the characteristic melting point is less than 300 °C, and preferably less than 200 °C, for example in the range from 100 °C to 200 °C.

8. The method of any one of the preceding claims, wherein the first substrate area (200a) is provided on a first substrate, and the second substrate area (200b) is provided on a separate second substrate.

9. The method of any one of the claims 1-7, wherein the first and second substrate areas (200a'; 200b') are provided on the same substrate, wherein the substrate is folded to bring the first substrate area and the second substrate area together.

10. and second substrate areas are provided on at least one web, the web(s) being provided in the form of roll(s) (102a; 102b; 102a'; 102b'), and wherein the method is a roll-to-roll process.

11. RFID transponders arranged on a carrying substrate forms RFID labels or RFID tags. The method of any one of the preceding claims, wherein the first The method of any one of the preceding claims, wherein the

12. The method of any one of the preceding claims, wherein the first antenna element (201a; 201a'; 201a”; 201a'”, 201B””) and the second antenna element (201b; 201b'; 201b”; 201b”'; 201b””) when electrically connected to the IC together form an antenna for the RFID transponder, wherein the first antenna element forms X% of the antenna and the second antenna element forms 100-X% of the antenna, where X >

13. one of the first antenna contact (203a) and the second antenna contact The method of any one of the preceding claims, wherein at least (203b) includes a conductive pad spanning substantially an entirety of the first external surface or the second external surface of the IC, respectively.

14. one of the first and second antenna elements are formed by conductive The method of any one of the preceding claims, wherein at least material in the form of electrically conductive solid particles.

15. forming of the conductive material in a pattern in at least one of the first and The method of any one of the preceding claims, wherein the second antenna elements comprises: transferring a conductive material in a pattern corresponding to said electrically conductive pattern to a surface of a substrate; and heating the conductive material to a temperature exceeding a characteristic melting temperature of the conductive material.

16. material to the surface of the substrate comprises direct printing of electrically The method of claim 15, wherein the transferring of conductive conductive particles as a part of a compound that contains, in addition of electrically conductive solid particles, a fluid or gelatinous substance.

17. applying a pressure onto the heated conductive material prior to arranging the IC (202) on the first substrate area (200a; 200a') and bringing the first substrate area and the second substrate area (200b; 200b') together.

18. (109; 109'), wherein the surface temperature of the nip is lower than said The method of claim 15 or 16, further comprising a step of The method of claim 17, wherein pressure is applied by a nip characteristic melting temperature.

19. transponder on a carrying substrate, comprising: An apparatus for producing a radio-frequency identificationan input station (101a; 101a') to receive one or more substrate, the substrate(s) having a first substrate area (200a; 200a') and a second substrate area (200b; 200b'), the first and second substrate areas each having at least one antenna element formed by an electrically conductive pattern arranged thereon, and preferably several antenna elements arranged sequentially thereon along a longitudinal extension of the first and second substrate areas, wherein a first antenna element (201a; 201a'; 201a”; 201a”', 201 B””) arranged on the first substrate area (200a; 200a') has a first antenna terminal (204a; 204a”'), and a second antenna element (201 b; 201 b'; 201b”; 201b”'; 201b””) arranged on the second substrate area (200b; 200b') has a second antenna terminal (204b; 204b'”); a placement device (106) arranged to place a dual-sided integrated circuit (IC) (202) on the first substrate area (200a; 200a'), the IC (202) including a first circuit block electrically coupled to a first antenna contact (203a), disposed on a first external surface of the IC, and a second antenna contact (203b), disposed on a second external surface of the IC opposite the first external surface of the IC, and wherein the IC (202) is placed on the first substrate area (200a; 200a') in such a way that the first antenna contact (203a) comes in mechanical contact with the first antenna terminal (204a; 204a”y a transfer device configured to bring the first substrate area (200a; 200a') and the second substrate area (200b; 200b') together, thereby bringing the second antenna contact (203b) in mechanical contact with the second antenna terminal (204b; 204b'); a heating device configured to heat the first and second substrate areas in the vicinity of the IC (202) to a temperature at least equal to a characteristic melting point of said first and second antenna terminals, thereby forming electric contact between the first antenna contact (203a) and the first antenna terminal (204a; 204a”'), and between the second antenna contact (203b) and the second antenna terminal (204b; 204b”').

20. The apparatus of claim 19, further comprising a pressing device arranged to press the first and second substrate areas against each other over the IC.

21. The apparatus of claim 20, wherein the pressure is applied by a nip (109), wherein the surface temperature of the nip is lower than said characteristic melting point.

22. The apparatus of any one of the claims 19 to 21, further comprising an adhesive applicator (105), arranged to provide an adhesive on at least one of the first and second substrate areas, the adhesive being arranged to adhere the first and second substrate areas together after the first and second substrate areas have been brought in mechanical contact.