Abstract:
An apparatus and method for providing a radio frequency identification (RFID) card, the card including a card inlay; an antenna positioned on the card inlay; a RFID integrated circuit (IC) located on the card inlay; an electrode structure; a switch located on or in the card inlay and, when actuated, coupled to the antenna and the RFID IC via the electrode structure. The switch further includes a conductive layer aligned with but positioned spaced apart from the electrode structure; and a compressible material to hold the conductive layer in the spaced apart position and to compress under pressure when the switch is actuated to permit the conductive layer to contact the electrode structure.

Description:
BACKGROUND 
       [0001]    In various implementations, a contactless smartcard may be used to implement a proximity payment and an identity card. A contactless smartcard may typically include a radio frequency identification (RFID) integrated circuit (IC) embedded in a card-shaped plastic body. An antenna may also be embedded in the card body to receive a power signal from a card reader such as, for example, a point of sale terminal. The antenna may also be used by the RFID IC to transmit an account number, cardholder identification, and other information to the POS terminal or other card reader. 
         [0002]    A contactless smartcard including a user-actuated switch may offer operational advantages such as enhanced security features. In some instances, a user may need to actuate the switch in order to activate the smartcard so that the smartcard may be read by a card reader. By requiring a user to actuate a switch included on the smartcard in order to activate the card, it may be possible to prevent certain security attacks against the card such as those initiated surreptitiously by reading a smartcard from a distance without the knowledge, consent, or authorization of the card holder. 
         [0003]    However, disadvantages that may be associated with a smartcard having a user-actuated switch is that the resulting cards may include increased manufacturing costs, decreased longevity or reliability of the smartcard, and non-conformance with industry standards related to the size, configuration, and dimensions of the smartcard. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a simplified schematic plan view of a contactless smartcard, according to some embodiments herein; 
           [0005]      FIG. 2  is schematic plan view of a card inlay, in accordance with some embodiments herein; 
           [0006]      FIG. 3  is an a schematic plan view of a contactless smartcard incorporating a mechanical switch, according to some embodiments herein; 
           [0007]      FIG. 4  is an a schematic plan view of another embodiment of a contactless smartcard incorporating a mechanical switch, according to some embodiments herein; and 
           [0008]      FIG. 5  is an exemplary flow chart illustrating aspects of a method for manufacturing a contactless smartcard, in accordance with some embodiments herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    In general, and for the purpose of introducing concepts of embodiments of the present disclosure, a contactless smartcard herein may include a RFID IC that is activated to an operational state by a mechanical switch incorporated into the smartcard. Using an RFID IC of the type disclosed herein may provide an efficient, reliable, and cost-effective proximity payment card that includes a user-actuated switch. This disclosure a reliable and cost effective method for incorporating a user-actuated switch into a smartcard. Importantly it allows the switch to be constructed within the inner layers of the card, and then sealed from outside contaminates using the outer layers. 
         [0010]      FIG. 1  provides an illustrative depiction of a contactless smartcard  100  including a card inlay  105 , a top outer layer  110  on a first side of card inlay  105 , and a bottom outer layer  115  on a second side of card inlay  105 . Card inlay  105  acts as a carrier for an antenna, a RFID IC, a mechanical switch, and other associated components as will be described in greater detail below. 
         [0011]    It should be recognized that for the economic production of such cards, multiple cards many be produced together from larger sheets of material. These sheets will then be cut or otherwise formed into individual cards. For the purpose of clarity of this description and not a limitation, reference is made to a single card. For example, although a single card including three layers is shown in  FIG. 1 , each layer shown may be a complex construction of several other layers (not shown). 
         [0012]    Card inlay  105  may resemble a payment card shape and size, including those adhering to industry standards regulating the size, shape, and configuration of payment cards. Top outer layer  110  and bottom outer layer  115  may, alone or in combination with other material layers (not shown), cooperate to retain card inlay  105  between top outer layer  110  and bottom outer layer  115 . 
         [0013]    A card lamination process may be used in a manufacturing process of card  100  to fix the relative positioning of top outer layer  110 , bottom outer layer  115 , and card inlay  105 . 
         [0014]    In some embodiments, card inlay  105  may be made of a material that is resistant to deformation when subjected to the heat and pressures present in a card manufacturing process, including those accompanying a lamination process. In particular, card inlay  105  may be configured to maintain its structural integrity when subjected to the combination of heat and pressures associated with a card lamination process to the extent that the constituent components of the card, e.g., an antenna, RFID IC, and other components, are not damaged when subjected to lamination pressures and heat. 
         [0015]    It should be appreciated that the size and shape of card inlay  105  and card  100  in general may be altered, modified, or otherwise changed to accommodate specific uses, implementations, and to conform to relevant standards regarding size, shape, and configuration that are now known and those that become known in the future. 
         [0016]      FIG. 2  provides a schematic overview of a card inlay  200 . Card inlay  200  includes a carrier body  205  that supports an antenna  210 , a RFID IC  215 , and switch electrode structure  220 . Carrier body may be flexible, thereby providing a resilient and robust structure that can withstand a card manufacturing process, as well as withstanding the hazards visited upon a card throughout the expected life cycle of the card. In some embodiments herein, antenna  210 , RFID IC  215 , and switch electrode structure  220  are contained either on or in card inlay  200 . In some embodiments, antenna  210  includes several loops or runs of wire or conductive material on carrier body  205 . Card inlay  200 , including carrier body  205 , antenna  210 , RFID IC  215 , and switch electrode structure  220  may typically have a height or thickness of about 0.5 mm or less. 
         [0017]    As illustrated, antenna  210  may include several loops of conductive material printed, etched, deposited, or otherwise positioned on or in card inlay  200 . While depicted as being located along a periphery of card inlay  205 , the exact positioning, size, and configuration of antenna  210  may be altered to accommodate various custom or standard design constraints. As such, the configuration and number of turns of antenna  210  are illustrative, not limiting aspects herein. In some embodiments, electrode structure  220  may comprise antenna  210 , in part or in full. 
         [0018]    Carrier body  205 , in some embodiments, is constructed of a material resistant to distortion during manufacturing and the operation pressures, stresses, and heat to which card inlay  200  is likely subjected to during the lamination process. In some embodiments, carrier body  205  may contain regions where different materials are used to ensure that a particular region of carrier body  205  is protected from distortion during manufacture. Accordingly, in some embodiments carrier body  205  will resist becoming soft during the card lamination process to an extent that components incorporated into the carrier body are damaged, or structures formed in the card carrier are distorted. 
         [0019]    Still referring to  FIG. 2 , switch electrode structure  220  provides a mechanism to electrically couple RFID IC  215  and antenna  210  together in a switched circuit with a user-actuated switch. In some embodiments, electrode structure  220  is an integral part of the user-actuated mechanical switch disclosed herein. In other embodiments still, portions of antenna  10  may functionally provide connection points or terminals for the mechanical switch(es) herein. 
         [0020]    Electrode structure  220  provides a mechanism, distinct from or part of an antenna wire or trace of antenna  210 , to facilitate a reliable electrical contact between RFID IC  215 , antenna  210 , and the user-actuated mechanical switch disclosed herein. 
         [0021]    Antenna  210  and RFID IC  215  may be connected to electrode structure  220  by bonding or a conductive paste, and any other method known now or that becomes known in the future that is compatible with the other aspects of the present disclosure. 
         [0022]    In some embodiments, RFID IC  215  may be positioned on card inlay  200  in a location to minimize a potential for capacitive coupling between the conductive trace connecting electrode structure  220  and RFID IC  215  and antenna  210 . Accordingly, RFID IC  215  is positioned away from antenna  210  in  FIG. 2 . 
         [0023]      FIG. 3  provides an illustrative depiction of some aspects of a smartcard  300  (or an inner layer within the smartcard) incorporating a mechanical switch consistent with the present disclosure. In particular, a top electrode structure  305  and a base electrode  315  are provided between an upper outer layer  320  and a lower outer layer  325 . Upper outer layer  320  and lower outer layer  325  may comprise plastic laminate layers of smartcard  300 . 
         [0024]    Positioned between top electrode  305  and base electrode  315  to maintain separation between the top electrode and the base electrode is a layer of compressible material  315 . Compressible material  315  does not fill a full extent of the area between top electrode  305  and base electrode  315 . Instead, at least a portion of the area between top electrode  305  and base electrode  315  is left uncovered or unoccupied by compressible material  315 . In this manner, top electrode  305  may be forced into contact with base electrode  310  when a downward (upward) force is registered against upper (lower) outer layer  320  ( 325 ), thereby compresses compressible layer  315  and urging top electrode  305  and base electrode  315  into contact with each other at the exposed area(s) between the electrodes. Compensation layer  330  provides, at least in some embodiments, a layer of material to compensate for a void created by the card inlay between upper outer layer  320  and lower outer layer  325 . 
         [0025]    In an operation to actuate the mechanical switch of smartcard  300 , compressible material  315  is compressed when a force is applied to the card, thereby reducing the gap separating top electrode  305  and base electrode  310  such that an electrical connection is established between the conductive top electrode and the conductive base electrode. In this manner, RFID IC  215  may be selectively connected to antenna  210  in a closed circuit. As the compressible material may only partly compress, either the base or top electrode may, in some embodiments, protrude towards the opposing electrode such that contact is made between the electrodes. 
         [0026]    In some embodiments, a card inlay including the mechanical switch disclosed herein may be formed from a number of constituent parts during the manufacture of the inlay and/or card. In other embodiments, the mechanical switch may be provided as a distinct assembled component that is provided on or in the card inlay at the appropriate time during the card or card inlay manufacturing process. 
         [0027]    In some instances herein, the mechanical switch is at least partially located in a cavity in card inlay  105 . Locating the switch at least partially in a cavity in the card inlay may facilitate producing a card and/or card inlay that does not exceed a maximum card and/or card inlay height restriction. Further minimizing or eliminating vertical features, or the edges of materials in the structure, will contribute to a uniform card or card inlay that meets design and technical specifications. 
         [0028]    In some embodiments, compressible material  315  may have a thickness of about 100 μm and about 300 μm. 
         [0029]    In some embodiments, top electrode  305  may be a rigid structured comprising a thin conductive (e.g., metal) plate. In some embodiments, a conductive (e.g., metallic) area may be applied to an underside of the upper outer layer  320  (or other layers) immediately above and opposing base electrode  310 . 
         [0030]    In some embodiments, particularly embodiments where top electrode  305  comprises a rigid conductive plate, the conductive plate may not be adhered to the layer immediately above it (e.g., upper outer layer  320 ). In this manner, top electrode  305  may be free to flex, bend, or otherwise move a rate or extent different than the upper outer layer. 
         [0031]    In some embodiments, top electrode  305  may be assured of being free to move in response to an applied pressure by being separated from upper outer layer  320  by way of the composition materials of upper outer layer  320  and top electrode  305  and/or a coating or layer of material disposed between upper outer layer  320  and top electrode  305 .  FIG. 4  provides an illustration of a smartcard similar to the smartcard of  FIG. 3  where similar components are similarly referenced (i.e.,  305  and  405  refer to upper outer layer, etc.) Unique to  FIG. 4 , a layer of material  435  may be provided between an upper (lower) electrode  405  ( 410 ) of a mechanical sensitive switch and an upper (lower) outer layer  420  ( 425 ) of a card  400 . The layer of material  435  may provide a mechanism to keep the upper (lower) outer layer  420  ( 425 ) from adhering to or otherwise bonding to the mechanical switch that includes top (base) electrode  405  ( 410 ). The material may be implemented in the form of a tape, film, spray-on application, spacer, etc. In some embodiments, the material be a polyimide film such as Kapton® tape provided by E. I. du Pont de Nemours and Company. 
         [0032]    Due to the operational force applied to the smartcard herein,  300 ,  400 , the size and rigidity of an electrode such as top electrode  305 ,  405  may be limited and an edge profile of the electrode may be designed to distribute forces over a large area. For example, the size of the switch structure (e.g.,  220 ) may be of the order of about 16 mm whereas the height of the gap separating the top and base electrodes may be on the order of about 0.1 mm. 
         [0033]    It is noted that the size of exposed electrodes may be dependant on the gap between the electrodes and the amount of distortion that can be reasonably expected in the electrodes during the life of the card. Although the electrodes would always return to their original shape after the force required to activate the switch is removed in an optimum situation, over time and multiple operations the electrodes or card may permanently distort to reduce the gap between the electrodes. Accordingly, a purpose of the compressible material is to maintain a reliable gap between the opposing electrodes during the entire operational life-cycle of the card. 
         [0034]    In some embodiments, compressible materials such as carbon nanotubes, microcellular foams, and cross linked polyolefin foams have exhibited properties suitable for providing the compressible material  315 ,  415 . For example, carbon nanotubes have been shown to behave like compressible springs, withstand about 10,000 cycles of compression without collapsing, as well as having a high heat resistance. Additionally, microcellular foams having a cell size of about (1-10) μm and cross-linked polyolefin foams having a cell size of about (20-100) μm have also exhibited characteristics consistent with those needed for the compressible material  315 ,  415  herein. 
         [0035]      FIG. 5  is a flow diagram of a process  500  that may be used in manufacturing a smartcard or card inlay, in agreement with various aspects herein. At operation  505 , an antenna and RFID IC are provided on a card inlay. The manufacturing process continues at operation  510  wherein an electrode switch structure is connected to the antenna on or in the card inlay. In some embodiments, the electrode structure switch is provided as an extension or part of the antenna, while in other embodiments that electrode switch structure is a distinct device coupled to the antenna. 
         [0036]    At operation  515 , a compressible material is located, disposed, or otherwise provided in a vicinity of the electrode switch structure. In some embodiments, the compressible material may be placed along a peripheral boundary of the electrode switch structure. 
         [0037]    At operation  520 , the top electrode of the electrode switch structure may be supported by the compressible material in an aligned and spaced apart relationship with the base electrode. It is noted that the compressible material does not completely fill an area between the top and base electrodes. Instead, at least a portion of the area between the top and base electrodes remains uncovered by the compressible material so that, when a compressive pressure is applied to the smartcard to actuate the mechanical switch, the top and base electrodes may establish conductive contact with each other. 
         [0038]    At operation  525 , the smartcard may be laminated using a lamination process. The lamination process may apply a combination of heat and pressure to the card inlay including the antenna, RFID IC, mechanical switch having top and base electrodes between a top outer layer adjacent a first side of the card inlay and a bottom outer layer adjacent a second side of the card inlay opposing the first side of the card inlay to enclose the card inlay between the top and bottom outer layers. 
         [0039]    In some embodiments herein, a card inlay may be produced using some of the operations of process  500 . That is, the card inlay may be produced as a separate or pre-stage operation prior to laminating the card inlay into a card during a card laminating process. 
         [0040]    By incorporating a mechanical switch in an inlay in the manner disclosed herein, it may be possible to incorporate a user-actuated switch in a smartcard while minimizing changes in the card manufacturing process, and also minimizing increases in manufacturing cost. 
         [0041]    Although not specifically indicated in the drawings, one or more of the contactless smartcards herein may have a contact interface like that of a conventional card that includes a contact interface. 
         [0042]    In some embodiments (not shown), the switch structure of the smartcard may not be connected directly to the antenna circuit, but instead via other circuit paths and/or components to the RFID IC  215 . In such cases, RFID IC  215  may not support an antenna or RF interface. 
         [0043]    The above description and/or the accompanying drawings are not meant to imply a fixed order or sequence of steps for any process referred to herein; rather any process may be performed in any order that is practicable, including but not limited to simultaneous performance of steps indicated as sequential. 
         [0044]    The contactless smartcards may also be applicable to contactless smart cards generally, as well as to so-called “dual interface” smart cards, which contain a set of contacts on a surface of the card to allow for direct contact interface to a terminal. “Dual interface” smart cards also include an antenna to allow for interfacing to a terminal by wireless transmission of signals. 
         [0045]    Although the present invention has been described in connection with specific exemplary embodiments, it should be understood that various changes, substitutions, and alterations apparent to those skilled in the art can be made to the disclosed embodiments without departing from the spirit and scope of the invention as set forth in the appended claims.