WO2005062246A1

WO2005062246A1 - Identification document

Info

Publication number: WO2005062246A1
Application number: PCT/IB2004/004202
Authority: WO
Inventors: Yves Reignoux; Séverine CHERAMY; Benoît Thevenot; Joseph Leibenguth; Denis Groeninck; Jean-Pierre Lafon
Original assignee: Axalto Sa
Priority date: 2003-12-19
Filing date: 2004-12-20
Publication date: 2005-07-07

Abstract

The invention relates to an identification document (21) and a method for making such a document. According to the invention, the identification document (21) comprises at least one flexible cover layer (25), at least one flexible internal page (22) and an electronic module (26) including a flexible support layer, an antenna positioned onto said flexible support layer and an electronic radio frequency microcontroller storing identification data, said microcontroller being affixed to said flexible support layer and electrically connected to said antenna, said module (26) being affixed to said flexible layer cover layer (25) or to said flexible internal page (22). The invention relates more particularly to electronic passports and visas.

Description

IDENTIFICATION DOCUMENT

The invention relates to identification documents and methods for making them. More particularly, it relates to identification documents such as passports, that constitute paper booklets and which contain personal data of their holder such as his/her name, birth date, address and photograph. Typically, smart cards, which are plastic cards comprising an embedded secured microcontroller, are well- known to contain this type of personal data in a secure manner. They may be used within an automatic recognition and/or transaction system for exchange of personal or confidential data with a remote central database, in order to allow smart card holders to access specific services or premises . Practically, smart cards are divided into two categories . Smart cards of a first category use contact pads to connect electrically the microcontroller to the outside world. Smart cards of a second category, often called contactless smart cards, uses radio frequency waves to communicate. Contactless smart cards are manufactured by lamination of an inlet between two or more plastic sheets. The inlet is a plastic sheet wherein a radio- frequency (RF) microcontroller and an antenna connected thereto are integrated. The characteristics of the radiofrequency interface used for contactless communication was defined by the International Standard Organization (ISO) in the standard referenced ISO-14443A and ISO-14443B. In many countries, national authorities desire that passports and visas are made more resistant against forgeries. In fact, such forgeries are easily achieved with paper documents . The security of said passports and visas would be improved by the integration of electronic means which would comprise identification data of their holder and would possibly include biographic and biometric authentication data. That is the reason why, the need to integrate a secured microcontroller with radio frequency (RF) capabilities inside a passport has emerged as a privileged way to combine the security of electronics with the easiness of connecting to central databases. Additionally, such electronic passports and visas would facilitate customs processing or border entries. However, the use of standard smart cards manufacturing processes for the manufacturing of passports or visas is not efficient. The resulting product is a passport with thick and rigid plastic cover or internal pages that is neither very appealing nor efficient. Considering the above, a problem intended to be solved by the invention is to develop an identification document such as a passport which offers the flexibility of a paper document but which integrates a RF component in a robust and secure manner for an extended period of time, for example, at least ten years. In particular, the identification document should be made so that any attempt to dismantle, attack or remove the electronic module would result in the functional disabling of the integrated circuit/antenna assembly and in a clear visible physical damage to said identification document being shown, said attempt being achieved through the use of heat, moisture, chemicals, sharp instruments or through the use of whatever other means. In a first aspect, the solution of the invention to this problem relates to an identification document comprising at least one flexible cover layer, at least one flexible internal page and an electronic module including a flexible support layer, an antenna positioned onto said flexible support layer and an electronic radio frequency microcontroller storing identification data, said microcontroller being affixed to said flexible support layer and electrically connected to said antenna, said module being affixed to said flexible cover layer or to said flexible internal page. In a second aspect, the solution of the invention relates to a method for making an identification document comprising at least one flexible cover layer, at least one flexible internal page and an electronic module including a flexible support layer, an antenna positioned onto said flexible support layer and an electronic radio frequency microcontroller storing identification data, wherein said method comprises: providing the flexible support layer, the antenna and the microcontroller; positioning said antenna on said flexible support layer; affixing the microcontroller onto said flexible support layer; electrically connecting the microcontroller to said antenna; and affixing the module onto the flexible cover layer or onto the flexible internal page. Advantageous features of the identification document according to the invention are: - the flexible cover layer and/or the flexible internal page are made of a fibrous material, for example paper or paperboard, or are made of plastic; - the flexible support layer is made of epoxy glass, PET, polyamide or Kapton™; - the flexible support layer has a thickness in the range 25 to 100 μm; - the flexible support layer comprises an aperture and the aperture is located within the surface defined by the antenna; - the flexible support layer comprises cuttings, said cuttings being located within the surface defined by the antenna or outside the surface defined by the antenna; - the flexible support layer comprises perforations close to its edges; - the flexible cover layer and/or the flexible internal page are provided with a cavity, the module being incorporated into said cavity;

- the flexible cover layer and/or the flexible internal page are made of plastic and the module is laminated into the plastic; - the identification document further comprises at least a spacer layer, said spacer layer being provided with a cavity; - the spacer layer is made of a fibrous material, for example, paper or paperboard, or is made of plastic, for example a soft plastic, or is made of glue; - the entire module is incorporated into the cavity or only the module part comprising the microcontroller is incorporated into the cavity, said cavity being advantageously filled with glue; - the identification document further comprises a layer, the module being positioned in between the flexible cover layer or the flexible internal page and said layer; - the microcontroller comprises a memory for storing visa related information; - the identification document is a passport, the flexible cover layer being part of the passport cover and the flexible internal page being an internal page of said passport; and - a substantial part of the passport cover comprises metallic wires defining a grid and constituting a magnetic shield. Advantageous features of the method according to the invention are: - the flexible cover layer and/or the flexible internal page are made of a fibrous material, for example, paper or paperboard, or are made of plastic;

- the method further comprises the step of providing the support layer with an aperture; - the method further comprises the step of providing a spacer layer comprising a cavity; - the module is incorporated in said cavity; - the module part comprising the microcontroller is incorporated into the cavity; - the method further comprises the step of positioning the module in between the flexible cover layer or the flexible internal page and a layer; - the method further comprises the step of providing the support layer with cuttings; - the flexible support layer and the flexible cover layer or the flexible internal page are laminated; and - the module is embedded or laminated into a multi-layer structure of the identification document. For a better understanding of the present invention, reference will now be made, by way of example, to the following description of the invention and to the accompanying drawings, in which: - figure 1 is a schematic cross-section illustrating a contactless smart card according to the prior art; figures 2A, 2B, 2C and 2D are views of identification documents according to a first, second, third and fourth embodiments of the invention; - figures 2E and 2F are, respectively, a front view and a cross-section of a passport cover according to an embodiment of the invention; - figures 3A to 3F are cross-sections of modules embodiments used in an identification documents according to the invention; - figures 3G, 3H and 31 are top views of modules that may be used in identification documents according to the invention; figures 4A to 4V are cross-sections or top views of the cover of identification documents according to the invention; and figures 5A to 5F are cross-sections of an internal page of identification documents according to the invention. Corresponding numerals and symbols in the figures refer to corresponding parts, unless otherwise indicated. In figure 1, a prior art module 10 is embedded inside a pre-laminated inlet 11. The module comprises an integrated circuit 12 connected to a support 13. The integrated circuit and. its connections are protected by a resin 14. The support 13 has electrical pads 15 connected to the integrated circuit . An antenna 16 is etched on a first plastic layer 17 of the inlet and not on the support. The antenna is connected to the electrical contact pads 15. Then, a second plastic layer 18 is laminated onto the first layer 17 to create the inlet 11. The inlet 11 is inserted between other external plastic layers 19 to finalise the contactless smart card. In a variant of the prior art, not represented, the manufacturing of the smart card uses Flip-Chip technology. Rather than using a module wherein the integrated circuit is bonded to the electrical pads 15 using connecting wires, said integrated circuit is turned over on the antenna and connected to the antenna pads using bumps. The pre- laminated inlet 11 of the prior art is rigid and has a typical thickness of 400 - 450 μm. The following embodiments of the invention relate to passports and visas. However, the invention may concern other identification documents comprising a paper paperboard layer such as identification cards. In a first embodiment of the invention, figure 2A, a passport 21 comprises a booklet of flexible pages 22 of paper and a flexible paper, paperboard or plastic cover 23. This cover 23 includes two layers : an internal layer 24 and a cover layer 25. An electronic module 26 is inserted between these two layers. In a second embodiment of the invention, figure 2B, the passport 21 is also made of a booklet of internal pages 22 and a cover 23. The cover includes two layers. The first layer 25 is the cover layer per se . The second layer 27 is a spacer layer. The spacer layer 27 comprises a cavity and the module 26 is positioned in said cavity so that it is flush with the spacer layer surface. In a third embodiment, figure 2C, the module 26 is positioned onto an internal paper page 22 of the passport 21. It is covered by a layer 28, which constitutes, in this embodiment, a self-adhesive paper visa. In a fourth embodiment, figure 2D, a substantial part of the passport cover 23 surface, advantageously, the entire surface or a substantial part of the surface of said passport cover 23, comprises embedded metallic wires defining a grid 29. When the passport 21 is closed, the grid 29 constitutes a shield to electro-magnetic waves. As the electronic module 26 is located inside the shielding area, contactless communications between said module 26 and the outside world, which are achieved through electro-magnetic waves, are limited or not possible. Thus, fraudulent data exchange with the electronic module 26 is not possible as long as the passport 21 is closed. When the passport is open, the electronic module may communicate with the outside world using electromagnetic waves. It is noted that, instead of a grid, the passport may comprise a full metallic foil or a coil . As shown in figures 2E and 2F, the thickness of the passport cover 23, comprising an electronic module 26, is advantageously substantially the same along its whole surface. This is due to the spacer layer 27, which is designed to compensate any variation in thickness that may occur along the cover. This spacer layer 27 is however preferably discontinuous at the passport hinge 59. This increases the passport flexibility at said hinge . Figures 3A to 31 illustrate various module embodiments according to the invention. The modules according to these embodiments are said coil-on-module as the antenna is part of the module itself and not part of a separate body like an inlet plastic sheet. In the embodiment of figure 3A, the module 26 includes a flexible support layer 30. This support layer 30 is made of a polymer material such as epoxy glass, PET (polyethylene terephtalate) , polyamide or Kapton™. Its thickness is in the range 50 — 150 μm, preferably in the range 50 - 100 μm, in order to achieve a high degree of flexibility. Using standard manufacturing techniques of the electronics printed board industry, an antenna 31 is etched onto the support layer 30. This antenna 31 has two contact pads 32 on which a RF microcontroller or component 33 is electrically connected by wire bonding. An epoxy resin 34 is dispatched on top of the microcontroller 33 and the bonding wires, in order to ensure their protection. As for the embodiment of figure 3A, the modules of figures 3B to 31 comprise a flexible support layer 30, a microcontroller 33 and an antenna 31, two bonding pads 37 of said microcontroller being electrically connected to terminals ends of the antenna 31 through connecting means 38, said microcontroller 33 and said connective means 38 being embedded into a protective resin 34. However, in these embodiments, the antenna 31 and the microcontroller bonding pads 37 are located at opposite sides of the support layer 30 so that said layer 30 includes at least two trough holes allowing connecting of said bonding pads to the antenna terminal ends. Also, a stiffener 40, generally made of epoxy or copper, is positioned onto the protective resin 34 in order to reinforce the modules 26 and improve their mechanical strength. If the stiffener is made of a metal such as copper or aluminium, it is advantageously insulated at least on one side, in fact on the particular side contacting the protective resin. Thus, if the stiffener 40, being positioned onto the protective resin, is in physical contact with the bonding wires, it will not cause any short-circuit. More specifically, in the module of figure 3B, a copper antenna 31 is glued to an epoxy support layer 30. The layer referenced 35 in said figure illustrates this glue. A cavity 36 is made in the support layer 30 and the microcontroller 33 is incorporated into said cavity with a view to make the module 26 thinner. The bonding pads 37 of the microcontroller 33 are electrically connected to the terminal ends of the antenna 31 via the bonding wires

38, through the holes 39. The thickness of such a module

26, comprising a 150 μm-thick microcontroller 33, is comprised between approximately 400 and 425 μm. The thicknesses of the various elements of this module 26 are as follows: Copper antenna 31 : 35 μm Glue 35 : 15 μm Epoxy layer 30 : 110 μm Resin 34 : 130 μm Epoxy stiffener 40 : 110 μm In figure 3C, the copper antenna 31 is connected to copper contact pads 41 by means of vias that are made through the flexible support 30. However, the microcontroller 33 is not positioned into a cavity of the epoxy support layer 30. It is glued on the upper side of said support layer 30, opposite to the antenna 31. The bonding pads 37 of the microcontroller 33 are electrically connected to the copper contact pads 41 placed on the upper side of the epoxy player. These contact pads 41 are electrically connected to the terminal ends of the antenna 31 through the holes 39 filled with a conductive resin (via) . The thickness of such a module 26, comprising a 50 μm-thick microcontroller, is of approximately 290 μm. The thicknesses of the various elements of this module are as follows -. Copper antenna 31 : 35 μm Lead-frame 30 : 70 μm Contact pads 41 : 35 μm Microcontroller glue : 20 μm Resin 34 : 130 μm Epoxy stiffener 40 : 55 μm. As in the module of figure 3B, the module of figure 3D comprises an epoxy support layer 30 and the microcontroller 33 is incorporated in a cavity 36 of said layer 30. However, in this embodiment, as in the embodiment of figure 3C, the epoxiy support layer 30 comprises copper contact pads 41 electrically connected to the terminal ends of the antenna 31 through connecting vias, the microcontroller 33 being connected to said contact pads 41 through bonding wires 38. The thickness of such a module 26, comprising a 88 μm-thick microcontroller 33, is of approximately 305 μm. The thicknesses of the various elements of this module are as follows : Copper antenna 31 : 35 μm Glue 35 : 20 μm Epoxy support layer 30 : 70 μm Contact pads 41 : 18 μm Resin 34 : 130 μm Epoxy stiffener 40 : 55 μm The structure of the module 26 of figure 3E is similar to the structure of the module of figure 3C. However, the thickness of the copper layer defining the antenna 31 is reduced so that the total thickness of the module 26, comprising a 50 μm-thick: microcontroller 33, is equal to approximately 263 +/- 50 μm. Practically, the thicknesses of the various elements of said module are as follows: Copper antenna 31 : 18 μm Epoxy support layer 30 : 70 μm Contact pads 41 : 18 μm Microcontroller glue : 20 μm Resin 34 : 120 μm Epoxy stiffener 40 : 55 μm Finally, in the module of figure 3F, the support layer 30 is not made of epoxy but of PET (polyethylene terephthalate) , the microcontroller 33 is not bonded to the contact pads with bonding wires but using bumps 42 (Flip-Chip) and the stiffener 40 is made of metal. The thicknesses of the various elements of such a module, comprising a 50 μm-thick microcontroller 33, is of approximately 226 μm. The thicknesses of the various elements are as follows: Copper antenna 31 : 18 μm PET support layer 30 : 70 μm Contact pads 41 : 18 μm Bumps 42 : 30 μm Stiffener 40 and glue : 40 μm Figure 3G illustrates a module 26 according to one of the embodiments of figures 3B to 3F. As appearing in this figure, the dimensions of the support layer 30 are considerably more important than the dimensions of the microcontroller 33. As a result, the antenna 31, which is positioned onto the support layer 30, defines an internal surface which is sufficient to allow an efficient inductive coupling distance of a few centimetres with a reader. Practically, the length the antenna 31 is comprised between approximately 25 and approximately 120 mm but is preferentially of approximately 80 mm, whereas its width is comprised between approximately 15 and approximately 100 mm but is preferentially of about 35 mm. Of course, the dimensions of the support layer 30 are grater than that. Also, the support layer 30 may present some perforations 44 close to its edges. These perforations are primarily used to displace the support layer 30 during the manufacture of the modules, prior to their cutting off. During lamination of the various layers of the module 26, the material of these layers may flux within said perforations and form rivets that will increase the mechanical strength of the multi-layer structure. Finally, it is to be noted that the internal zone of the support layer, illustrated by the doted line in figure 3G and referenced 43, may be removed and, in particular, punched out from the module 26. In such a case, the support layer 30 presents a central aperture. Due to this central aperture, the flexibility of the module is improved. Moreover, the epoxy surface is reduced so that the risk of delamination between the spacer layer and the last page of the passport or the internal cover page (in case of a 3 -layer construction) is lowered. Figure 3H illustrates a module 26 wherein the support layer 30, in particular, the specific part of said support layer located within the antenna windings, is provided with cuttings 53-1. For example, these cuttings 53-1 may define a star located approximately centrally at the support layer surface or they may define various other patterns. The terminal ends of these cuttings are advantageously close to the antenna windings. It is however essential that the cuttings do not extend to the antenna itself. As a result of these cuttings, the electronic module 26 is weakened. Practically, when attempts are made to remove an electronic module 26, as in the present embodiment, from a passport 21, pulling forces are applied onto the support 30. These pulling forces may cause the cuttings to extend up to the antenna itself and generate a short circuits or a breakage of the antenna. As a result of this attempt, the electronic module may not operate. In figure 31, the internal zone 43 has been punched out from the support layer 30 so that the support layer 30 presents a central aperture 54. In this embodiment, the cuttings may be located at the periphery of the aperture (cuttings 53-2) or at the periphery of the support layer 30 (cuttings 53-4), , in between the perforations 44 (cuttings 53-3) or close the microcontroller 33 (cuttings 53-5) . Again, in this case, the module 26 is weakened so that fraudulent attempts to pull out said module 26 from the passport will result in a destruction of the support layer and of the antenna. In accordance with the invention, the module as in figures 3A to 31 is embedded into a passport as in figures 2A to 2D. This may be achieved as in figures 4A to 4V or as in figures 5A to 5F. As shown in figure 4A, the cover layer 25 of the passport cover includes a cavity 45. This cavity 45 is used to glue the module 26 and the internal layer 24 is laminated on top of the cover layer 25 with a view to protect the module 26. In figure 4B, the layer 25 of the passport cover does not include any cavity. A Spacer layer 27 is glued to said layer 25. This spacer layer 27 comprises a through hole defining a cavity 46. The module part comprising the microcontroller and the resin reinforced by the stiffener is incorporated into said cavity 46 whereas the module part comprising the support layer 30 and the antenna lays above the spacer layer 27. Moreover, the module 26 and the spacer layer 27 are covered by an adhesive internal layer 24. The glue, which is used to stick - the spacer layer 27 to the cover layer 25, - the module 26 to the spacer layer 27, and - the internal layer 24 to the spacer layer 27 and to the module 26, can be a solvent, water-based pressure sensitive adhesive (PSA) , a PU (polyurethane) glue or a hot melt glue applied for thermal bonding. In figure 4C, the passport cover layer 25 does not include any cavity as well. The spacer layer 27 is glued to said passport cover layer 25. This spacer layer 27 includes a cavity 46. The entire module 26 is incorporated in said cavity 46 which is filled with one or more layers of glue 47. The glue may be a PU or hot melt type glue. The total thickness of the glue inside the cavity 46 may be of approximately 240 μm. There is no internal layer covering the embedded module 26 and the antenna located on the support layer 30 is flush with the spacer layer 27 surface. As a result, the passport cover in accordance with this embodiment only includes two layers, a first layer corresponding to the cover itself and a second layer corresponding to the spacer layer in which is incorporated the entire module, as in figure 2B. The support layer of the module is visible at the spacer surface. For very thin modules 26, the spacer layer 27 may not be essential so that said module may be only glued on the inner side of the passport cover layer 25. Figures 4D to 4P illustrate preferred embodiments according to the invention wherein the cavity 46, in which is incorporated the module part comprising the microcontroller 33 and the protective resin 34, but excluding the support layer 30, is filled with glue 57. The glue 57 advantageously fills the entire cavity 46. Preferably, it is able to stick efficiently to the stiffener 40, to the protective resin 34 and to fibrous or plastic materials such as the fibrous or plastic material that may constitute the cover layer 23 and the spacer layer 27. Additionally, the glue 57 is capable of remaining stable under relatively elevated temperatures . It is expected that fraudulent persons, intending to remove the electronic module 26 from the passport, will try to heat up the glue 57. As this glue 57 remains stable under relatively elevated temperatures, for example of about 80°C, it will not be possible to remove the module 26 in such a manner. Fraudulent persons will have to pull out the module by applying pulling forces to said module. Due to the presence of the glme 57, these pulling forces will disaggregate the module 26. More specifically, the embodiments of figures 4D, 4E and 4F present three superposed layers : the cover layer 25, the spacer layer 27 and the internal layer 24. The cavity 46 is made in the spacer layer 27. The support layer 30 of the electronic module 26 is located between the spacer layer 27 and the internal layer 24. Advantageously, as shown in figure 4E, the support layer 30 comprises cuttings 53-1 so that, if pulling forces are applied on the electronic module 26, the antenna 31 will disaggregate. Alternatively, as shown in figure 4F, the support layer 30 may comprise a central apex-ture 54. In this case, the support layer may present cuttings 53-2, 53-3 and/or 53-4, as in figure 31. The embodiment of figures 4G and 4H is similar to the previous embodiments of figure 4D to 4F. However, in this embodiment, the support layer 30 is glued to the cover layer 25. As a result, there is an additional glue layer 55 between the spacer layer 27 and the internal layer 24. This glue layer 55 is thicker at the periphery of the support layer 30 and inside the central aperture 54 of the module 26, as shown in figure 4H. It reinforces the whole structure of the passport cover including the module. Removal of this module 26 from the cover is made more difficult. In the embodiment of figures 41 and 4J, the electronic module 26 is positioned upside-down and glued to the cover layer 25 by means of a glue layer 55. The spacer layer 27, provided with the cavity 46, is located immediately above the glue layer 55. The resulting three- layer structure, may be covered by an internal layer 24 or not. In any case, the antenna 31 is facing the cover layer 25 and is embedded in the glue layer 55. As a result, pulling forces, that would be applied on the structure, with a view to remove out the module, would destroy the antenna, in particular, if the support layer 30 is provided with cuttings and, possibly, with a central aperture, as in figures 3H or 31. In figures 4K and 4L, the spacer layer 55 is made of paper or plastic. The electronic module 26 is glued to the cover layer 25 using a glue layer 55. This glue layer is relatively thick and comprises a cavity 46. The module part comprising the microcontroller is embedded is said cavity 46. Furthermore, the support layer 30 comprises a central aperture 54. In the embodiment of figures 4M and 4N, as in the embodiment of figures 41 and 4J, the module 26 is upside- down and the support layer 30 is glued to the cover layer 25 via a glue layer 55. However, in this embodiment, the glue layer is not covering the entire surface of the cover layer 23 but is only located in between the support layer 30 and the cover layer 25. A further glue layer 56, provided with the cavity 46 incorporating the module part including the microcontroller, is positioned above the support layer 30. The embodiment of figures 40 and 4P presents four superposed layers: a cover layer 25, a glue layer 55 a spacer layer 27 and an internal layer 24. The spacer layer 27 is smaller in length than the other layers so that there is an empty space 58 in between the glue 55 and internal 24 layers. This empty space 58 is located close to the passport hinge. It increases the flexibility of said hinge . In the embodiment of figure 4Q, the electronic module is positioned upside-down and the support layer 30 of this module is glued to the cover layer 25. There are two spacer layers: a first spacer layer 27-1 and a second spacer layer 27-2. The first spacer layer 27-1 is glued to the cover layer 25 through a first glued layer 55-1. The thickness of the first spacer layer 27-1 is approximately equal to the thickness of the support layer 30. The thickness of the second spacer layer 27-2 is approximately equal to the thickness of the module 26 less the thickness of the support layer and the thickness of a second glue layer 55-2 in between the second spacer layer 27-2 and the first spacer layer or the support layer 30. The passport cover also comprises an internal layer 24 glued to the second spacer layer 27-2 through a third glue layer 55-3. The layers 25, 27-1, 27-2 and 24 are all made of paper. They are co-laminated with thermo glue and the electronic module in order to form a flexible cover structure of the passport. In the embodiment of figure 4R, as in the embodiment of figure 4Q, there are a unique cover layer 25, a module 26 positioned upside-down, and two spacer layer 27-1 and 27-2, said layers being glued through glue layers 55-1 and 55-2. However, there are two internal layers: a first internal layer 24-1 and a second internal layer 24-2, provided with a cavity 46. The layers 27-1 and 27-2 are made of plastic. They are co-laminated with the module 26 and glue in order to constitute a pre-laminate . The layers 25, 24-1 and 24-2 are glued to this pre-laminate at a later stage. These layers 25, 24-1 and 24-2 may be made of paper or of plastic. The thicknesses of the various layers of this embodiment are as follows-. Cover layer 25 and glue 55-1 : 350 μm First spacer layer 27-1 : 70 μm Second spacer layer 27-2 and glue -. 210 μm First internal layer 24-1 and glue 55-3 : 70 μm Glue 55-4 : 20 μm Second internal layer 24-2 : 100 μm In the embodiments of figures 4S and 4T, there is a unique spacer layer 27 made of a soft plastic. This soft plastic is, for example, made of PVC, PETG or Teslin™ (a polyolefin-based plastic comprising non abrasive filler and air) . The Vicat point of the PVC that may be used is comprised between 50 and 80. It is for example 75. The module 26 is advantageously pre-coated with glue. In figure 4S, the passport cover comprises a cover layer 25, a glue layer 55-1, a module 26 positioned upside-down, a further glue layer 55-2, a spacer layer 27 made of a soft plastic and provided with a cavity 46, a glue layer 55- 3, a first internal layer 24-1 made of plastic or paper, a glue layer 55-4 and a second internal layer 24-2 made of paper. For the manufacture of such a passport cover, a pre-laminate is made under relatively low temperatures

(soft lamination) and possibly using specific glue that may be activated under IR or other electro-magnetic waves. This pre-laminate comprises the layers 25 and 55-

1, the module 26, and the layers 55-2, 27-, 55-3 and 24- 1. As the spacer layer 27 is soft, it will deform during lamination and the module 26 will perfectly integrate the cover structure so that said structure will be perfectly flat. Additionally, as the module is tightly maintained in the structure, it is extremely difficult to remove said module from the cover. Practically, it is impossible to remove said module without causing irreversible damages to said module or to the cover layer . The various thicknesses of the layer of this embodiment are as follows : Cover layer 25 and glue 55-1 : 350 μm Soft plastic layer 27 and glue 55-2 : 280 μm First internal layer 24-1 and glue 55-3 : 70 μm Glue 55-4 : 20 μm Second internal layer 24-2 : 100 μm In figure 4T, the spacer layer 27 is even not provided with a cavity. In fact, advantage is taken from the characteristics of soft plastic to laminate the module into the flexible plastic layer without the need of a cavity. The Vicat point of the soft plastic which constitutes the spacer layer is sufficiently high to allow the entire module to integrate said spacer layer and the glue layers 55-1 or 55-2. Here also a pre- laminate is made with the layers 25, 55-1, 55-2 and 27 and enclosing the module 26. The cover layer is advantageously made of plastic. Thus, the pre-laminate is said of the type full plastic. The internal page 24 made of paper is glued to the pre-laminate at a later stage. The thicknesses of the various layers are as follows: Cover layer 25 and glue 55-1 : 350 μm Soft plastic layer 27 and glue 55-2 : 350 μm Glue 55-3 : 20 μm Internal layer 24 : 100 μm The embodiment of figure 4U is similar to the embodiment of figure 4S. However, the spacer layer 27, made of a soft plastic, is not provided with a cavity 46. In the embodiment of figure 4V, there are two spacer layers 27-1 and 27-2 which are made of glue. When the cover layer 25, the first spacer layer 27-1, the module 26, the second spacer layer 27-2 and a first internal layer 24-1 are laminated (soft lamination) , the module 26 perfectly integrates the glue layers 27-1, 27- 2. The module 26 is also perfectly maintained in the glue layers so that it may not be removed from the whole structure without destruction of the passport cover or of the module itself. The various thicknesses of the layers are as follows: Cover layer 350 μ.τn Glue spacer layer 27-1 3 x S 5 μm Glue spacer layer 27-2 3 55 μm Paper or plastic first internal layer 24-1 : 70 μm Glue 55 : 20 μm Second internal layer : 100 μm. In a further embodiment, not shown in the drawings, the passport cover comprises an external cover of 330 μm- thick, a glue spacer layer of a hot melt type and of 65 μm-thick, a coil-on-module having a 70 μm-thick support layer if said layer is made of epoxy of a 30 μm-thick support layer if said layer is made of copper, and three layers of glue of 65 μm-thick each, the first two glue layers comprising an aperture for facilitating the incorporation of the support layer and of the module part comprising the integrated circuit. Advantageously, on top of this structure is positioned an internal paper layer of 70 μm-thick. The presence of this paper layer perrαits to avoid adherence of the glue to the lamination plates, the laminated structure being then easily removed from said plates. This further embodiment is said "full glue" or "full polymer" as the glue is of a polymeric nature . Figures 5A to 5F illustrate embodiments wherein the electronic module 26 is attached to an internal page 22 of the passport, and is associated with a visa 28 in order to constitute an electronic visa. In figure 5A, the module is embedded into a spacer layer 27 as in figure 4C. However, this spacer layer 27 and the module 26 are positioned onto an internal page 22 of the passport and not onto the cover layer 25. In the represented configuration, the module is thinner and the thickness of the PU or hot melt type glue is of approximately 175 μm. In figure 5B, a module as in figures 3B to 3E is positioned upside-down on a passport internal page 22. Thus, the microcontroller part of the module 26 is located above the support layer 30 when affixed to said passport page 22. The module 26 is affixed to the passport page using glue 48. The visa is glued to the module and the passport page using a glue 49. The glue does not compensate the thickness of the module so that the electronic visa presents a protrusion corresponding to said module. Therefore, the electronic visa presents various thicknesses along its cross-section: 100 μm corresponding to the thickness of the passport page 22, 170 μm corresponding to the thickness of the passport page plus the thickness of the visa 28 and associated glue, 430 μm corresponding to the addition of the previous 170 μm plus the support layer 30 and associated glue 48 and 645 μm corresponding to the previous 430 μm plus the microcontroller part of the module. In figure 5C, a module as in figures 3B to 3E is affixed on a passport page in such a way that the microcontroller part is positioned under the support layer 30, between said support layer and the passport page 22. As compared to the embodiment of figure 4R, the electronic visa of this embodiment presents a thick glue layer 48 which compensates the thickness of the microcontroller part of the module, said microcontroller part being included into a cavity 50 of said thick glue layer. As a result, the electronic visa does not present any protrusion due to the microcontroller part of the module and the electronic visa cross-section shown in figure 4S presents three thicknesses along its cross- section: 100 μm corresponding to the thickness of the passport page 22, 170 μm corresponding to the thickness of said passport page plus the thickness of the visa 28 and associated glue; and 595 μm corresponding to the previous 170 μm plus the thickness of the module and associated glue. In figure 5D, the paper visa and associated glue are provided with a cavity 51 and the module is included in said cavity, the antenna 31 of said module appearing at said visa surface. Practically, the various thicknesses along the electronic visa profile of this embodiment are as follows: 100 μm for the passport page; 500 μm for the passport page, the visa per se and the glue; and 525 μm for the passport page and the module. It is noted that the electronic visa configuration of figure 5D may be used with an thin coil-on-module . The total thickness of this electronic module is then of approximately -250 - 350 μm. In the embodiment of figure 5E, the module 26 is positioned upside-down, as in figure 5B . However, the visa 28 and corresponding glue layers include a cavity and the microcontroller part of the module is included in said cavity 52. Thus, the electronic visa profile presents three thicknesses: 100 μm corresponding to the thickness of the passport page 22; 260 μm corresponding to the thickness of the passport page 22 and the visa 28 and associated glue 49; and 575 μm corresponding to the thickness of the module 26 and the passport page 22. in this embodiment, only the back side of the module, i.e. the stiffener is appearing at the visa surface. The embodiment of figure 5F is similar to the embodiment of figure 5E but the coil-on-module is thinner- and the microcontroller part of the module is embedded into the visa and corresponding glue layers so that the total thickness of the electronic visa is of approximately 380 μm. In the embodiments of figures 4C, 5A and 5D, the coil-on-module itself is embedded into the layers 25 and 27 (figures 4C and 5A) or into the layers 22, 49 and 28 (figures 5D) . Technologies associated with embedding of modules are generally well controlled by card manufacturers and in particular by the applicant of the present patent application. Additionally, the embedding of a module may be done in a very last step of the manufacture of the identification document according the invention. The previous various layers of an electronic passport or an electronic visa according to the invention are glued or laminated. A paper or plastic laminate is then obtained and, when finished, the passport incorporating the module 26 appears similar to a standard passport . Except for the small area where the RF microcontroller is positioned, the flexibility of the cover or page is close to the flexibility of the cover or page of a standard passport. Anyway, said cover or said page are more flexible than a smart card as defined in the ISO standards. Furthermore, the module and all electronic components are, according to some embodiments of the invention, invisible. The previous embodiments were described for a passport or visa comprising one electronic module, said electronic module comprising one electronic component (microcontroller) . However, it will be obvious for the person skilled in the art to accommodate the technology described hereby to passports and visas comprising a plurality of modules or to modules comprising a plurality of electronics components. For example, a battery can be added to the module in order to supply the electrical energy to the RF component or a mechanical switch enabling or disabling the antenna function. In another example, a display may be integrated to the passport cover. The module antenna is advantageously etched. However, it may be screen printed using a conductive ink or obtained from a process such as electrolysis wherein a conductive ions are accumulated within a particular zone to define an antenna. Moreover, the antenna may be a thermo-sonic embedded wire in a plastic substrate. The RF micro-controller is chosen among the standard micro-controllers for smart cards. For instance, the ST19RF08 from STMicroelectronics™ has the processing power, data storage, security and RF interface. With these types of processors, it is possible to integrate different applications on the same chip. For a passport, in parallel with the personal data contained in the passport itself, the microcontroller contains and processes electronics visas. Visa information, such as validity, stay, countries visited, place of issue, date of issue are electronically downloaded in the passport with a contactless transmitter in consulates or official places that issue visas. The traveller's information is then displayed and verified when transiting through a customs clearance area in various destination countries. Thereafter, an electronic stamp, equivalent to a physical stamp, is written by the customs clearance personnel into the microcontroller upon verification and clearance.

Claims

1. An identification document (21) comprising at least one flexible cover layer (25) , at least one flexible internal page (22) and an electronic module (26) including a flexible support layer (30) , an antenna (31) positioned onto said flexible support layer (30) and an electronic radio frequency microcontroller (33) storing identification data, said microcontroller (33) being affixed to said flexible support layer (30) and electrically connected to said antenna (31) , said module (26) being affixed to said flexible cover layer (25) or to said flexible internal page (22) .

2. The identification document (21) of claim 1, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of a fibrous material.

3. The identification document (21) of claim 2, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of paper or paperboard.

4. The identification document (21) of claim 1, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of plastic.

5. The identification document (21) of one of claims 1 to 4, wherein the flexible support layer (30) is made of epoxy glass, PET, polyamide or Kapton™.

6. The identification document (21) of one of claims 1 to 5, wherein the flexible support layer (30) has a thickness in the range 25 to 100 μm.

7. The identification document (21) of one of the previous claims, wherein the flexible support layer (30) comprises an aperture (54) , said aperture being located within the surface defined by the antenna (31) .

8. The identification document (21) of one of the previous claims, wherein the flexible support layer (30) comprises cuttings (53-1, 53-2, 53-3, 53-4, 53-5).

9. The identification document (21) of claim 8, wherein the cuttings (53-1) are located within the surface defined by the antenna (31) .

10. The identification document (21) of claim 8, wherein the cuttings (53-2, 53-3, 53-4, 53-5) are located outside the surface defined by the antenna (31) .

11. The identification document (21) of one of the previous claims, wherein the flexible support layer (30) comprises perforations (44) close to its edges.

12. The identification document (21) of one of the previous claims, wherein the flexible cover layer (25) and/or the flexible internal page (22) are provided with a cavity (45) , the module (26) being incorporated into said cavity.

13. The identification document (21) of one of the previous claims, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of plastic and the module (26) is laminated into the plastic.

14. The identification document (21) of one of the previous claims, further comprising at least a spacer layer (27) .

15. The identification document (21) of claim 14, wherein the spacer layer is provided with a cavity (46) .

16. The identification document (21) of one of claims 14 or 15, wherein the spacer layer (27) is made of a fibrous material.

17. The identification document (21) of one of claims 14 or 15, wherein the spacer layer (27) is made of plastic, preferentially a soft plastic.

18. The identification document (21) of claim 14, wherein the spacer layer is made of glue.

19. The identification document (21) of claim 16, wherein the entire module (26) is incorporated into the cavity (46) .

20. The identification document (21) of claim 15, wherein only the module part comprising the microcontroller (33) is incorporated into the cavity (46) .

21. The identification document (21) of one of claims 19 or 20, wherein the cavity (45, 46) is filled with glue .

22. The identification document (21) of one of the previous claims, further comprising a layer (24, 28), the module (26) being positioned in between the flexible cover layer (22) or the flexible internal page (25) and said layer (24, 28) .

23 . The identification document (21) of any one of the preceding claims, wherein the identification document is a passport (21) , the flexible cover layer (25) being part of the passport cover (23) and the flexible internal page (22) being an internal page of said passport.

24. A method for making an identification document (21) comprising at least one flexible cover layer (25) , at least one flexible internal page (22) and an electronic module (26) including a flexible support layer (30) , an antenna (31) positioned onto said flexible support layer (30) and an electronic radio frequency microcontroller (33) storing identification data, wherein said method comprises : providing the flexible support layer (30) , the antenna (31) and the microcontroller (33) ; positioning said antenna (31) on said flexible support layer (30) ; affixing the microcontroller onto said flexible support layer (30) ; electrically connecting the microcontroller (33) to said antenna (31) ; and affixing the module (26) onto the flexible cover layer (25) or onto the flexible internal page (22) .

25. The method of claim 24, -wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of a fibrous material.

26. The method of claim 25, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of paper or paperboard.

27. The method of claim 24, wherein the flexible cover layer (25) and/or the flexible internal page (22) are made of plastic.

28. The method of one of claims 24 to 27, further comprising: providing the support layer (30) with an aperture (43) .

29. The method of one of claims 24 or 28, further comprising providing a spacer layer (27) .

30. The method of claim 29, wherein the spacer layer comprises a cavity (46) .

31. The method of claim 30, wherein the module (26) is incorporated in said cavity (46) .

32. The method of claim 30, wherein the module part comprising the microcontroller (33) is incorporated into the cavity (45) .

33. The method of one of claims 24 to 32, further comprising positioning the module (26) in between the flexible cover layer (22) or the flexible internal page (25) and a layer (24, 28) .

34. The method of one of claims 24 to 33, further comprising: providing the support layer (30) with cuttings (53-1, 53-2, 53-3, 53-4, 53-5).

35. The method of one of claims 24 to 34, wherein the flexible support layer (30) and the flexible cover layer (25) or the flexible internal page (22) are laminated.

36. The method of one of claims 24 to 34, wherein the module (26) is embedded or laminated into a multi- layer structure of the identification document (21) .