GB2552390A

GB2552390A - Method of manufacturing an electronic card

Info

Publication number: GB2552390A
Application number: GB1614056.8A
Authority: GB
Inventors: Colussi Steven; Monteil Edward
Original assignee: Zwipe AS
Current assignee: Zwipe AS
Priority date: 2016-07-19
Filing date: 2016-08-17
Publication date: 2018-01-24
Also published as: WO2018015131A1; GB201614056D0

Abstract

Method of manufacturing an electronic smartcard comprising forming an upper layer 22 with a through hole for receiving a biometric sensor assembly. Forming a lower layer 24. Joining the layers together around a flexible electronic circuit 26. Before lamination attaching a biometric sensor assembly 130 to the circuit, the sensor provided with a protective covering 34 having a melting point the same or higher than the upper and lower layers. After lamination removing the covering to expose the sensor. The sensor assembly may comprise sensor and a surrounding bezel 32. The protective covering provided within the bezel. The sensor is preferably a fingerprint scanner and the bezel is preferably conductive. The upper and lower layers are preferable polyvinylchloride (PVC) the melting point of the cover is preferably at or above 160 ºC. The cover may be applied to the sensor as a liquid thermosetting material, more preferably the covering is room temperature vulcanising silicone. The covering may be applied as a solid, preferably comprising PVC. Removal of the covering may be via a suction deice or a jet of fluid. Also included are claims to an electronic card comprising a flexible circuit, upper and lower layers and a biometric sensor exposed at the card surface.

Description

(54) Title of the Invention: Method of manufacturing an electronic card Abstract Title: Method of manufacturing an electronic card (57) Method of manufacturing an electronic smartcard comprising forming an upper layer 22 with a through hole for receiving a biometric sensor assembly. Forming a lower layer 24. Joining the layers together around a flexible electronic circuit 26. Before lamination attaching a biometric sensor assembly 130 to the circuit, the sensor provided with a protective covering 34 having a melting point the same or higher than the upper and lower layers. After lamination removing the covering to expose the sensor.

The sensor assembly may comprise sensor and a surrounding bezel 32. The protective covering provided within the bezel. The sensor is preferably a fingerprint scanner and the bezel is preferably conductive. The upper and lower layers are preferable polyvinylchloride (PVC) the melting point of the cover is preferably at or above 160 °C. The cover may be applied to the sensor as a liquid thermosetting material, more preferably the covering is room temperature vulcanising silicone. The covering may be applied as a solid, preferably comprising PVC. Removal of the covering may be via a suction deice or a jet of fluid. Also included are claims to an electronic card comprising a flexible circuit, upper and lower layers and a biometric sensor exposed at the card surface.

Fig. 5

At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy. At least some of the priority details shown above were added after the date of filing of the application.

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METHOD OF MANUFACTURING AN ELECTRONIC CARD

The present invention relates to a method of manufacturing an electronic card, such as the type of card known as a smartcard. Particularly, the present invention relates to a method of manufacturing an electronic card that includes a biometric sensor.

A smartcard is a pocket-sized card with an embedded integrated circuit. A smartcard typically contains volatile and non-volatile memory and microprocessor components.

A typical smartcard is manufactured by laminating a flexible printed circuit assembly between two layers of plastic. Polyvinyl chloride (PVC) is commonly used for this purpose as it softens before it oxidises and, at suitably high temperatures and pressures, will flow and conform to the shape of components on the printed circuit assembly. When using PVC, or similar substances, the laminating temperatures required can be as high as 200°C or 250°C.

Smartcards provide a way of authenticating the bearer of the card and carrying a secure message from the card to the reader. For example, if a nonsmart credit card were to be lost or stolen, an unauthorised user would be able to use the credit card until the credit card is cancelled. Conversely, a smart credit card may include many more levels of security that would prevent such use by an unauthorised user. One such security measure that may be used with a smartcard is the analysis of biometric data to positively identify the bearer of the card. A biometric security measure may be added to a smartcard through the addition of a biometric sensor, such as a fingerprint sensor, on the card. In the case of a fingerprint sensor when the smartcard is to be used, the bearer presents their finger or thumb to the sensor which then allows for an associated processor to positively identify the owner of the finger or thumb and hence confirm that the user is an authorised user of the smartcard.

Smartcards have developed considerably over the last few years, and the industry has had to implement innovative manufacturing methods for integrating all components within the card while also aiming to meet ISO 7810 and ISO 7816 specifications for the cards. Prior art smartcards are typically manufactured using a hot lamination process, in which upper and lower laminate layers are heated and pressed together about an inlay on which various components are mounted. In typical smartcards, the laminate layers are formed of PVC, which is melted during the lamination process, and the inlay can be a polyamide flexible printed circuit board, which does not melt.

WO 2013/160011 discloses a method for manufacturing a smartcard in which the use of a biometric sensor is facilitated by producing a preformed card body including a circuit having contacts for connection to the biometric sensor. The contacts are embedded within the preformed card body during lamination and a cavity is formed in the preformed card body after lamination in order to expose the contacts. Thus, according to WO 2013/160011 the card body including a circuit can be pre-formed by a conventional technique, with a cavity later being formed to expose contacts and allow insertion of the biometric sensor. This concept provides significant advantages and allows for a biometric sensor to be used without exposure of the biometric sensor to the high temperatures and pressures of the lamination process. However, there remains a need for further advances in this area in order to ensure that electronic cards such as smartcards can be manufactured easily and reliably whilst including complicated and potentially sensitive electronics.

Viewed from a first aspect, the present invention provides a method of manufacturing an electronic card, wherein the finished electronic card comprises a flexible electronic circuit, an upper laminate layer located above the flexible electronic circuit, a lower laminate layer located below the flexible electronic circuit, and multiple components mounted on an upper surface of the flexible electronic circuit, the components including a biometric sensor with a sensing region that is exposed at the card surface; the method comprising: forming the upper laminate layer with a through hole for receiving the biometric sensor; assembling the upper laminate layer with the flexible electronic circuit and the lower laminate layer; and joining the laminate layers to each other and around the flexible electronic circuit by lamination to thereby enclose the flexible electronic circuit between the upper and lower laminate layers; wherein before the lamination step the biometric sensor is attached to the flexible electronic circuit; wherein the biometric sensor is provided with a removable protective covering on the sensing region, the protective covering having a melting point the same as or higher than that of the upper and lower laminate layers; and wherein the method comprises carrying out the lamination step whilst the protective covering is present and later removing the protective covering to expose the sensing region.

As a result of using the temporary protective covering it is possible to form the electronic card via a lamination process, preferably a hot lamination process, with a reduced risk of moving and/or damaging the biometric sensor or the structure of the card around the sensor. The protective covering can provide a shield to protect the sensing region and other parts of the sensor from heat and/or pressure generated during lamination. The biometric sensor will be electrically attached to the flexible electronic circuit, but there may be no additional mechanical connection between the biometric sensor and the circuit and/or laminate layers. Without the added protection from the protective covering then the pressure applied by lamination may cause the biometric sensor to move, potentially resulting in air bubbles and/or unwanted melting or deformation of the lower laminate layer and/or flexible electronic circuit. There is also a risk of damage to the sensitive parts of the sensor from heat and/or pressure.

Thus, the protective covering may be for providing thermal insulation and/or mechanical protection to the biometric sensor. In particular, the protective covering may evenly distribute pressures across the sensor, minimising the risk of movement during lamination, and minimising the risk of creating a damaged or weakened electronic card. Whilst methods have been proposed that allow for the biometric sensor to be assembled with the card after lamination, as in WO 2013/160011 for example, this means that the manufacturing method of WO 2013/160011 can require more steps, and there are constraints on the order of the manufacturing steps. Advantages therefore arise from the use of the proposed technique since lamination is carried out with the biometric sensor already present and a temporary protective covering protects the biometric sensor during lamination.

The protective covering may be removed by any suitable technique after lamination. In some examples a suction device is used to lift the protective covering off the sensing region. In other examples a jet of fluid such as pressurised air can be used to remove the protective covering. The jet of fluid may be directed at an oblique angle to the surface of the electronic card.

Preferably the biometric sensor is for identification of an authorised user of the electronic card. The electronic card may be arranged to be fully operable only when the biometric sensor provides an indication of an authorised user. The electronic card may have secure features that are only accessible to an authorised user, with the biometric sensor providing a way to identify an authorised user.

The electronic card may have a biometric sensor assembly including the biometric sensor and a bezel surrounding the sensing region of the biometric sensor. The bezel may frame the sensing region. In this case, the protective covering may be provided within the bezel, preferably with a close fit to the perimeter of the bezel that frames the sensing region. The bezel may have a thickness on top of the sensing region, and thus may extend above the sensing region. The protective covering preferably has a thickness that is about the same as, or exactly the same as, the height/thickness of the bezel above the sensing region. The protective covering may have a constant thickness across the extent of the sensing region. This helps to ensure even distribution of pressure during the lamination process.

As used herein references to height and relative locations above and below other parts are described with reference to a direction through the thickness of the layers of the electronic card where the upper laminate layer is at the top and the lower laminate layer is at the bottom. The relative locations such as upper, lower, top and bottom are also specified relative to an upper and lower direction of the flexible electronic circuit in which the upper direction references parts at the surface of the circuit upon which the majority of components or all of the components are mounted, and the lower direction references parts at the other surface of the circuit.

The biometric sensor may be a fingerprint sensor with the bezel around the sensing region advantageously being an electrically conductive bezel that can provide an electrical field for use with the fingerprint sensor. For example, the fingerprint sensor may be a capacitive type fingerprint area sensor.

The lamination preferably comprises a hot lamination process. The upper laminate layer and/or the lower laminate layer are preferably formed from a material that is softened or melted during the hot lamination procedure. Suitable materials include thermoplastics, for example, polyvinyl chloride (PVC), polyethylene (PE), polycarbonate (PC). PVC is most commonly used and hence is selected in the example embodiment as discussed below. The melting point of PVC is typically 160°C and the melting point of PET is typically 250°C, so the melting point for the protective covering should be at or above 160°C or 250°C respectively, if PVC or PET is used for the laminate layers.

The method may include applying the protective covering as a liquid form of a thermosetting material. The thermosetting material has a melting point after the thermosetting process that is the same as or higher than the melting point of the upper and lower laminate layers, and optionally a melting point higher than the intended lamination temperature. Thus, the protective covering can be moulded directly onto the sensor and then allowed to set into a form that is more resistant to the temperature of lamination than the laminate layers. Applying the protective covering in a liquid form ensures a close fit with the sensing region and, when a bezel is used, with the perimeter of the bezel. Alternatively, the protective covering may be applied as a solid material with a melting point that is the same as or higher than the melting point of the laminate layers and optionally higher than lamination temperature. The use of a solid material may provide advantages in ease of handling and the time required to apply the protective covering.

The melting point of the protective covering may be about 160°C or above 160°C when PVC is used as the laminate layers, and could optionally be above 200°C where the lamination temperature is 200°C, which may be used for lamination of PVC.

Where a thermosetting process is used when applying the protective covering then this may involve cross-linking such as vulcanisation. Thermosetting polymer materials may be used for the protective covering. Such materials can either be applied as a liquid that solidifies to form the protective covering or the same materials may be applied as a solid protective covering. One example that may be applied in liquid form is room temperature vulcanising silicone rubber (RTV silicone). RTV silicone can resist temperatures of 205°C and higher. A material applied as a solid layer may be PVC or PET, for example. PVC has a melting point of about 160°C and PET can resist temperatures up to and above 250°C.

With the use of RTV silicone then a suction device is the preferred way to remove the protective covering. Any RTV silicone that remains adhered to the sensing region after suction removal can be cleaned off via mechanical cleaning or using a suitable solvent. Where a solid protective covering is used then the removal of the protective covering may be done via a suction device or via a jet of fluid as discussed above.

The through hole in the upper laminate layer for the biometric sensor may open over contacts on the flexible electronic circuit that are arranged for electrical connection to the biometric sensor. The number and layout of contacts may vary depending on the configuration of connection points in the sensor. The contacts may be gold or gold plated.

The method may comprise connecting the biometric sensor to the contacts on the flexible electronic circuit. This could be done at any suitable point during the manufacturing process prior to lamination, including before or after the upper laminate layer is placed in layered arrangement with the flexible electronic circuit, and before or after the lower laminate layer is placed in layered arrangement with the flexible electronic circuit. In some cases it may be advantageous to connect the biometric sensor to the flexible electronic circuit at the same time as other components are connected to the flexible electronic circuit.

The flexible electronic circuit may be assembled on a substrate of a flexible material using known processes for assembly of flexible electronic circuits. The flexible electronic circuit can then be layered with the two laminate layers. The substrate of the flexible electronic circuit may be a flexible circuit board made from a material of a higher melting point than the laminate layers, such as a polyamide flexible printed circuit board.

The upper and lower laminate layers may be the same size. Typically they are both larger in size than the flexible electronic circuit (when the circuit is fully separate to the two layers) in order that the material of the two laminate layers may join together and be fused together during lamination in order to fully seal the flexible electronic circuit between them. Hot lamination is used in order to join the layers together. This could be done by use of only the parts of the laminate layers that extend in size greater than the flexible electronic circuit. There may also be one or more orifice(s) through the flexible electronic circuit enabling fusing of the upper laminate layer to the lower laminate layer through the orifice(s). The use of one or more orifice(s) in this way can strengthen the bond between the laminate layers and therefore increase the structural integrity of the encapsulation of the flexible electronic circuit. It can also reduce or entirely avoid the need for resins that bond the laminate layers to the electronic circuit.

The upper laminate layer and the lower laminate layer may be of similar shape and about the same size in terms of their length and width dimensions. Their thickness may differ. Typically, the upper laminate layer will be thicker than the lower laminate layer due to the need to allow space for components on the upper surface of the flexible electronic circuit to extend into the material of the upper laminate layer. The laminate layers may both be made of the same material. This allows for greater freedom in selecting materials and processes used for attaching the laminate layers to each other. The total thickness of the lower laminate layer may be in the range 20-100 pm. If the electronic card is intended to be provided with a magnetic strip on the lower surface of the lower laminate layer, which is an optional feature, then it is advisable to have a minimum thickness of about 80 pm.

In cases where there is no magnetic strip then the lower laminate layer may be of lesser size to minimise the card thickness and/or allow for a greater thickness to house the internal components. The total thickness of the upper laminate layer may be in the range 500-600 pm, for example about 540 pm.

It is preferred for the upper surface of the upper laminate layer and optionally the lower surface of the lower laminate layer to be generally flat. The method may hence include using a flat substrate to form the upper and/or lower laminate layers. The card surfaces may be flat enough to meet ISO requirements for smartcards. An overlay, such as a printed overlay, may be provided on one or both of the outer surfaces after the laminate layers and the flexible electronic circuit have been attached together.

The walls of the through hole for receiving the biometric sensor may be coated with an adhesive epoxy prior to the biometric sensor being inserted. The adhesive epoxy seals the sensor in place to prevent the biometric sensor becoming dislodged and being disconnected from the circuit. Alternatively or additionally the biometric sensor may be mounted to the circuit using surface mounting technology.

A conductive epoxy may be used to connect the biometric sensor to the contacts. This ensures a good ohmic contact between the sensor and the contacts within the through hole. The conductive epoxy may be selected so that its curing temperature is low enough not to damage the biometric sensor. An epoxy that cures at room temperature may be used.

The conductive epoxy may be an anisotropic conductive adhesive such as an anisotropic conductive paste or an anisotropic conductive film. The use of anisotropic conductive means that substantial conduction does not occur between the contacts even if any of the adhesive spills over or overlaps between the contacts. This allows more freedom in selecting the technique/apparatus that applies the conductive adhesive, since less accuracy is required.

The flexible electronic circuit may include a processor and a memory. The memory may be arranged to store biometric information relating to an authorised user of the card and the processor may be arranged to compare the stored biometric information to biometric information acquired by the biometric sensor. Thus, the processor is preferably arranged to determine if the user is an authorised user based on an indication provided by the biometric sensor. The processor and memory may also be arranged to store and transmit other information associated with the electronic card to a reader, wherein the transmitted information does not include the stored biometric information and the biometric information acquired by the biometric sensor. The processor is preferably arranged such that the biometric information acquired from the sensor is never transferred from the card during normal operation.

The electronic card may include an antenna for wireless transmission of data, for example via RFID or similar. The electronic card may include a payment chip. An example embodiment includes a payment chip together with a biometric sensor and the processor is arranged to permit some or all financial transactions only if the identity of the user is confirmed as an authorised user by the biometric sensor.

The method of the above aspect may be used to manufacture electronic cards for a number of purposes where it is necessary for the identity of the bearer of the electronic card to be verified. For example, an electronic card manufactured in accordance with the above aspect may be any one of: an access card; a credit card; a debit card; a pre-pay card; a loyalty card; an identity card; and a cryptographic card. As discussed above, the electronic card is preferably arranged to be inoperable if the biometric sensor does not provide an indication of an authorised user. Thus, the electronic card may provide its desired function, or full functions, only when the biometric information confirms that the user is authorised. For example, where the electronic card is an access card, the access card may provide access only when the user is authorised.

The method may include forming multiple upper laminate layers together, for example from a single sheet of material. The assembly process may then include providing a flexible electronic circuit for each upper laminate layer, along with other associated parts (such as the biometric sensor and so on), providing a lower laminate layer for each upper laminate layer and flexible electronic circuit, and then attaching each set of parts together to form multiple cards which may then be separated, for example via cutting or stamping to form multiple individual cards.

Viewed from a second aspect the present invention provides an electronic card including a circuit having contacts and a biometric sensor connected to the contacts, the electronic card having been formed by any of the above methods.

In another aspect, the present invention provides an electronic card comprising: a flexible electronic circuit; an upper laminate layer located above the flexible electronic circuit; a lower laminate layer located below the flexible electronic circuit; multiple components mounted on an upper surface of the flexible electronic circuit, the components including a biometric sensor with a sensing region that is exposed at the card surface; and a through hole in the upper laminate layer for receiving the biometric sensor; wherein the upper laminate layer and lower laminate layer are joined to each other and around the flexible electronic circuit by lamination so that the flexible electronic circuit is enclosed between the upper and lower laminate layers; wherein the biometric sensor has been attached to the flexible electronic circuit prior to the lamination step and protected during lamination by a removable protective covering on the sensing region, with the removable protective covering having been removed after lamination.

An electronic card formed with the biometric sensor in place during lamination and using a protective covering as described herein will differ from electronic cards formed using prior art techniques, since the lamination process has a different effect on the structure of the electronic card. A card as in this aspect will have the laminate layers laminated around the biometric sensor as well as around the other components of the flexible electronic circuit, whilst avoiding unwanted deformation or air bubbles due to movement of the sensor during lamination. The electronic card may include any of the optional features or combinations of features mentioned above.

Certain preferred embodiments of the present invention will now be described in greater detail by way of example only and with reference to the accompanying schematic drawings, in which:

Figure 1 shows a circuit schematic for a smartcard having a fingerprint sensor;

Figure 2 shows a smartcard with a laminated body;

Figure 3 is a schematic cross-section of a laminated smartcard prior to lamination;

Figure 4 shows a similar cross-section to Figure 3, with a protective covering in solid form about to be installed on the fingerprint sensor; and

Figure 5 shows a similar cross-section to Figure 3 and Figure 4 with a protective covering present on the fingerprint sensor and the smartcard being ready for lamination.

The example electronic card takes the form of a biometric authorised smartcard as shown in Figure 2 and can incorporate a flexible electronic circuit laid out as in Figure 1. It should be noted that for clarity the thicknesses of the various parts shown in Figures 3 to 5 has been exaggerated significantly. In implementations of electronic cards of the type illustrated in the Figures the width of the card might be 7cm whereas the thickness of the card would be less than 1mm: a total thickness between the outer layers of 762 pm is typical for an ID-1 card that is ISO7810 compliant.

By way of example the invention is described in the context of a fingerprint authorised smartcard that includes contactless technology and uses power harvested from the card reader. These features are envisaged to be advantageous features of one application of the proposed manufacturing method, but are not seen as essential features. The smartcard may hence alternatively use a physical contact and/or include a battery providing internal power, for example. The method of manufacture described herein can also be implemented with appropriate modifications in any other device or system that is manufactured using a lamination process and uses a fingerprint sensor or similar biometric sensor for authorisation.

Figure 1 shows the architecture of a smartcard 102. A powered card reader 104 transmits a signal via an antenna 106. The signal is typically 13.56 MHz for Ml FARE® and DESFire® systems, manufactured by NXP Semiconductors, but may be 125 kHz for lower frequency PROX® products, manufactured by HID Global Corp. This signal is received by an antenna 108 of the smartcard 102, comprising a tuned coil and capacitor, and then passed to a communication chip 110. The received signal is rectified by a bridge rectifier 112, and the DC output of the rectifier 112 is provided to processor 114 that controls the messaging from the communication chip 110.

A control signal output from the processor 114 controls a field effect transistor 116 that is connected across the antenna 108. By switching on and off the transistor 116, a signal can be transmitted by the smartcard 102 and decoded by suitable control circuits 118 in the sensor 104. This type of signalling is known as backscatter modulation and is characterised by the fact that the sensor 104 is used to power the return message to itself.

An accelerometer 16, which is an optional feature, is connected in an appropriate way to the processor 114. The accelerometer 16 can be a Tri-axis Digital Accelerometer as provided by Kionix, Inc. of Ithaca, New York, USA and in this example it is the Kionix KXCJB-1041 accelerometer. The accelerometer senses movements of the card and provides an output signal to the processor 114, which is arranged to detect and identify movements that are associated with required operating modes on the card as discussed below. The accelerometer 16 may be used only when power is being harvested from the powered card reader 104, or alternatively the smartcard 102 may be additionally provided with a battery (not shown in the Figures) allowing for the accelerometer 16, and also the related functionalities of the processor 114 and other features of the device to be used at any time.

The smartcard further includes a fingerprint authentication engine 120 including a fingerprint processor 128 and a fingerprint sensor assembly 130. As described in more detail below, the fingerprint sensor assembly 130 includes a fingerprint sensor with a sensing region 30 and a bezel 32 that surrounds the sensing region 30, which is at an upper surface of the fingerprint sensor and is exposed for contact with the user's finger when the smartcard 102 is in use. The fingerprint sensor assembly 130 and fingerprint authentication engine 120 allow for enrolment and authorisation via fingerprint identification. The fingerprint processor 128 and the processor 114 that controls the communication chip 110 together form a control system for the device. The two processors could in fact be implemented as software modules on the same hardware, although separate hardware could also be used. As with the accelerometer 16 (where present) the fingerprint sensor assembly 130 may be used only when power is being harvested from the powered card reader 104, or alternatively the smartcard 102 may be additionally provided with a battery (not shown) allowing power to be provided at any time for the fingerprint sensor assembly 130 and fingerprint processor 128, as well as the processor 114 and other features of the device.

The antenna 108 comprises a tuned circuit including an induction coil and a capacitor, which are tuned to receive an RF signal from the card reader 104. When exposed to the excitation field generated by the sensor 104, a voltage is induced across the antenna 108.

The antenna 108 has first and second end output lines 122, 124, one at each end of the antenna 108. The output lines of the antenna 108 are connected to the fingerprint authentication engine 120 to provide power to the fingerprint authentication engine 120. In this arrangement, a rectifier 126 is provided to rectify the AC voltage received by the antenna 108. The rectified DC voltage is smoothed using a smoothing capacitor and then supplied to the fingerprint authentication engine 120 and other electrical components. Alternatively or additionally a battery may be included as noted above.

The fingerprint sensor assembly 130 is fitted so as to be exposed from a laminated card body 140 as shown in Figure 2. The laminated body 140 encases all of the components of Figure 1, and is sized similarly to conventional smartcards. It is manufactured in accordance with the method described below with reference to Figures 3 to 5. The fingerprint authentication engine 120 may be passive, and hence may be powered only by the voltage output from the antenna 108. Alternatively a battery (not shown) may be provided for powering the fingerprint authorisation engine 120. The processor 128 comprises a microprocessor that is chosen to be of very low power and very high speed, so as to be able to perform fingerprint matching in a reasonable time.

The fingerprint authentication engine 120 is arranged to scan a finger or thumb presented to the fingerprint sensor assembly 130 and to compare the scanned fingerprint of the finger or thumb to pre-stored fingerprint data using the processor 128. A determination is then made as to whether the scanned fingerprint matches the pre-stored fingerprint data. In a preferred embodiment, the time required for capturing a fingerprint image and authenticating the bearer of the card 102 is less than one second.

If a fingerprint match is determined and/or if appropriate movements are detected via the accelerometer 16, then the processor takes appropriate action depending on its programming. In this example the fingerprint authorisation process is used to authorise the use of the smartcard 104 with the contactless card reader 104. Thus, the communication chip 110 is authorised to transmit a signal to the card reader 104 when a fingerprint match is made. The communication chip 110 transmits the signal by backscatter modulation, in the same manner as the conventional communication chip 110. The card may provide an indication of successful authorisation using a suitable indicator, such as a first LED 136.

The fingerprint processor 128 and the processor 114 may receive an indication of a non-fingerprint interaction with the fingerprint sensor assembly 130, which can include any action detectable via the fingerprint sensor assembly 130. The interaction of the user with the card via the fingerprint sensor assembly 130 may be used as a part of a non-fingerprint authorisation and also may be used to allow the user to control the smartcard by switching between different operating modes of the smartcard.

In some circumstances, the owner of the fingerprint smartcard 102 may suffer an injury resulting in damage to the finger that has been enrolled on the card 102. This damage might, for example, be a scar on the part of the finger that is being evaluated. Such damage can mean that the owner will not be authorised by the card 102 since a fingerprint match is not made. In this event the processor 114 may prompt the user for a back-up identification/authorisation check via an alternative interaction with the smartcard 102, which in this case includes one or more action(s) detected via the fingerprint sensor assembly 130 and also optionally actions detected via other sensors, such as the accelerometer 16. The card may prompt the user to use a back-up identification/authorisation using a suitable indicator, such as a second LED 138. It is preferred for the non-fingerprint authorisation to require a sequence of interactions with the card by the user, this sequence being pre-set by the user. The pre-set sequence for non-fingerprint authorisation may be set when the user enrols with the card 102. The user can hence have a non-fingerprint authorisation in the form of a “password” entered using non-fingerprint interactions with the card to be used in the event that the fingerprint authorisation fails. The same type of non-fingerprint authorisation can be used in the event that a user is unable or unwilling to enrol with the card 102 via the fingerprint sensor assembly 130.

Thus, as well as allowing communication via the circuit 110 with the card reader 104 in response to a fingerprint authorisation via the fingerprint sensor assembly 130 and fingerprint processor 128 the processor 114 may also be arranged to allow such communication in response to a non-fingerprint authorisation.

When a non-fingerprint authorisation is used the card 102 could be arranged to be used as normal, or it could be provided with a degraded mode in which fewer operating modes or fewer features of the card 102 are enabled. For example, if the smartcard 102 can act as a bank card then the non-fingerprint authorisation might allow for transactions with a maximum spending limit lower than the usual maximum limit for the card 102.

The processor 114 receives the output from the accelerometer 16 and this allows the processor 114 to determine what movements of the smart card 102 have been made. The processor 114 identifies pre-set movements and other actions of the user that are linked with required changes to the operating mode of the smartcard. As discussed above, the movements may include any type of or combination of rotation, translation, acceleration, impulse and other movements detectable by the accelerometer 16. The other actions of the user may include actions detected via the fingerprint sensor, such as taps, swipes and so on.

The operating modes that the processor 114 activates or switches to in response to an identified movement associated with the required change in operating mode may include any mode of operation as discussed above, including turning the card on or off, activating secure aspects of the card 102 such as contactless payment, or changing the basic functionality of the card 102 for example by switching between operating as an access card, a payment card, a transportation smartcard, switching between different accounts of the same type (e.g. two bank accounts), switching between communications protocols (such as blue tooth, Wifi, NFC) and/or activating a communication protocol, activating a display such as an LCD or LED display, obtaining an output from the smartcard 102, such as a one-time-password or the like, or prompting the card 102 to automatically perform a standard operation of the smartcard 102.

The processor 114 has an enrolment mode, which may be activated upon first use of the smartcard 102. In the enrolment mode the user is prompted to enrol their fingerprint data via the fingerprint sensor assembly 130. This can require a repeated scan of the fingerprint via the fingerprint sensor assembly 130 so that the fingerprint processor 128 can build up appropriate fingerprint data, such as a fingerprint template. After a successful or an unsuccessful enrolment of fingerprint data the user is prompted to enter a non-fingerprint authorisation. This could be optional in the case of a successful fingerprint enrolment, or compulsory if the fingerprint enrolment was not successful. The non-fingerprint authorisation includes a sequence of interactions with the smartcard 102 including at least one action by the user that is detected via the fingerprint sensor assembly 130. The processor 114 can keep a record of these interactions in a memory, and it is arranged to provide at least partial authorisation to use the functions of the card in the event that the non-fingerprint authorisation is provided by the user.

The processor 114 can have a learn mode to allow for the user to specify which actions (including combinations of actions/interactions) should activate particular operating modes whilst the smartcard 102 is in use. This type of control of the smartcard 102 might be enabled only after a successful fingerprint or non15 fingerprint authorisation. In the learn mode the processor 114 prompts the user to make the desired sequence of actions, and to repeat the movements for a predetermined set of times. These movements are then allocated to the required operating mode or to the non-fingerprint authorisation. With this latter feature the learn mode can allow for the sequence of movements used for the non-fingerprint authorisation to be changed by the user in the same way that a traditional PIN can be changed.

A method of manufacturing ofthe smartcard 102 including the fingerprint sensor assembly 130 will now be described with reference to Figures 3 to 5. It should be noted that for the sake of clarity the Figures are shown in schematic form with exaggerated scale. It will be appreciated that the actual sizes of the various parts, in particular their heights, are much less that shown and that the parts would fit together more closely than indicated in the drawings.

After manufacturing is completed the smartcard 102 has a laminated body 140, and this is formed using a layered structure as in Figures 3 to 5. The layered structure is made up of an upper laminate layer 22, a lower laminate layer 24 and a flexible electronic circuit 26, which is between the two laminate layers 22, 24. The laminate layers 22, 24 may be made of PVC or other material suitable for use in creating laminated smartcards 102. There are various components attached to the flexible electronic circuit 26, including the fingerprint sensor assembly 130. The fingerprint sensor assembly 130 is made up of an area fingerprint sensor with a sensing region 30 and a bezel 32. The bezel 32 frames the sensing region 30 and is made of a conductive material, such as a suitable metal or metal alloy. This means that the bezel 32 can provide an electrical field in order to provide the capacitive effect that is used by the fingerprint sensor to generate a scan of the user's fingerprint (or thumbprint) that can be used for biometric authorisation of secure features of the smartcard 102. Typically the sensing region 30 is rectangular or square and the bezel 32 has the same rectangular or square shape.

The fingerprint sensor assembly 130 is connected to the flexible electronic circuit 26 before lamination of the card. In addition, also prior to lamination, a protective covering 34 is placed on top of the sensing region 30 on the fingerprint sensor assembly 130. The protective covering 34 can be a solid layer as shown in Figure 4, or it may be applied to the fingerprint sensor assembly 130 in a liquid form and then allowed to set. In either case the end result is as shown in Figure 5, where the protective covering 34 sits on top of the fingerprint sensor assembly 130, fitting closely and ideally completely filling the sensing region 30 that is enclosed within the perimeter of the bezel 32. The protective covering 34 has a constant thickness and is designed to be about or exactly the same height as the bezel 32.

The protective covering 34 remains in place during the hot lamination process that forms the final smartcard 102 with laminated body 140. It adds a temporary layer of structural firmness that prevents the fingerprint sensor assembly 130 from moving during lamination. Since the fingerprint sensor assembly 130 is not mechanically attached to the flexible electronic circuit 130 (aside from via mechanically weak electrical connections), then it has a tendency to move during the lamination procedure, which results in air bubbles or in melting on the underside of the lower laminate layer 24 underneath the fingerprint sensor assembly's location. As well as this, there is a risk of damage to the fingerprint sensor itself due to the heat and/or pressure of the lamination process. Placement of the protective covering 34 on the sensor surface is a simple step to ensure a successful lamination free of any damage to the smartcard and without blemishes to the smartcard’s surface.

The protective covering 34 should have a melting temperature that is the same or higher than the melting point of the laminate layers 22, 24. This ensures that the protective covering 34 is suitably resistant to the heat of the lamination process. In one example, the laminate layers 22, 24 are PVC and the protective covering 34 is also PVC, which is provided in solid form and applied as an added solid layer atop the sensing region. In another example the laminate layers 22, 24 are PVC and the protective covering 34 is room temperature vulcanisation silicone (RTV silicone), which is applied in liquid form to the sensor assembly and then allowed to solidify and vulcanise before lamination.

After lamination has been completed the protective covering 34 is removed, for example using a suction device, or with a jet of fluid directed at the sensor assembly 130 at an oblique angle. A vacuum suction device is well-suited to removal of an RTV silicone protective covering 34, with any remaining silicone being later cleaned from the sensing region 30 using known methods. A jet of high pressure air at an oblique angle, for example at 45°, is effective at removing a solid PVC protective covering 34. After the protective covering 34 has been removed then the manufacturing process may be finished or there may be additional steps such as the addition of printing to the surfaces of the card or personalisation of the smartcard 102 before it is issued to the end user.

Claims

CLAIMS:

1. A method of manufacturing an electronic card, wherein the finished electronic card comprises a flexible electronic circuit, an upper laminate layer located above the flexible electronic circuit, a lower laminate layer located below the flexible electronic circuit, and multiple components mounted on an upper surface of the flexible electronic circuit, the components including a biometric sensor with a sensing region that is exposed at the card surface; the method comprising:

forming the upper laminate layer with a through hole for receiving the biometric sensor;

assembling the upper laminate layer with the flexible electronic circuit and the lower laminate layer; and joining the laminate layers to each other and around the flexible electronic circuit by lamination to thereby enclose the flexible electronic circuit between the upper and lower laminate layers;

wherein before the lamination step the biometric sensor is attached to the flexible electronic circuit;

wherein the biometric sensor is provided with a removable protective covering on the sensing region, the protective covering having a melting point the same as or higher than that of the upper and lower laminate layers; and wherein the method comprises carrying out the lamination step whilst the protective covering is present and later removing the protective covering to expose the sensing region.

2. A method as claimed in claim 1, wherein the electronic card comprises a biometric sensor assembly including the biometric sensor and a bezel surrounding the sensing region of the biometric sensor, wherein the protective covering is provided within the bezel with a close fit to the perimeter of the bezel.

3. A method as claimed in claim 2, wherein the protective covering has a thickness that is about the same as, or exactly the same as, the height/thickness of the bezel above the sensing region.

4. A method as claimed in claim 1 or 2, wherein the biometric sensor is a fingerprint sensor and the bezel around the sensing region is an electrically conductive bezel that can provide an electrical field for use with the fingerprint sensor.

4. A method as claimed in claim 1, 2 or 3, wherein the material of the laminate layers is PVC and the melting point of the protective covering is equal to or above about160°C.

5. A method as claimed in any preceding claim, comprising applying the protective covering to the sensing region as a liquid form of a thermosetting material, wherein the thermosetting material has a melting point after the thermosetting process that is the same as or higher than the melting point of the upper and lower laminate layers.

6. A method as claimed in any preceding claim, wherein the protective covering is a thermosetting polymer material.

7. A method as claimed in any preceding claim, wherein the protective covering is room temperature vulcanising silicone that is applied to the sensing region in liquid form.

8. A method as claimed in any preceding claim, wherein the protective covering is applied as a solid material.

9. A method as claimed in any preceding claim, wherein the protective covering comprises PVC.

10. A method as claimed in any preceding claim, comprising using a suction device to remove the protective covering after lamination.

11. A method as claimed in any of claims 1 to 9, comprising using a jet of fluid to remove the protective covering after lamination.

12. A method as claimed in any preceding claim, comprising connecting the biometric sensor to contacts on the flexible electronic circuit before or after the upper laminate layer is placed in layered arrangement with the flexible electronic circuit, and before or after the lower laminate layer is placed in layered arrangement with the flexible electronic circuit.

13. A method as claimed in any preceding claim, comprising coating the walls of the through hole for receiving the biometric sensor with an adhesive prior to attaching the biometric sensor to the flexible electronic circuit.

14. A method as claimed in any preceding claim, comprising using a conductive epoxy to connect the biometric sensor to the flexible electronic circuit.

15. An electronic card including a circuit having contacts and a biometric sensor connected to the contacts, the electronic card having been formed by the method of any preceding claim.

16. An electronic card comprising: a flexible electronic circuit;

an upper laminate layer located above the flexible electronic circuit; a lower laminate layer located below the flexible electronic circuit; multiple components mounted on an upper surface of the flexible electronic circuit, the components including a biometric sensor with a sensing region that is exposed at the card surface; and a through hole in the upper laminate layer for receiving the biometric sensor; wherein the upper laminate layer and lower laminate layer are joined to each other and around the flexible electronic circuit by lamination so that the flexible electronic circuit is enclosed between the upper and lower laminate layers; and wherein the biometric sensor has been attached to the flexible electronic circuit prior to the lamination step and protected during lamination by a removable protective covering on the sensing region, with the removable protective covering having been removed after lamination.

Intellectual

Property

Office

Application No: GB1614056.8 Examiner: Dr Peter Aspinall