Abstract:
The invention concerns a contact-free microcircuit card ( 10 ) used in combination with a receiver ( 40 ) for carrying out an electronic transaction, incorporating a keyboard ( 12 ) for inputting data used during the transaction.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a microcircuit card of the contact-free type used in conjunction with a receiver to carry out an electronic transaction. 
   2. Description of the Related Art 
   In this patent application the expression “electronic transaction” is to be understood in a broad sense, and may in particular refer to a commercial transaction such as obtaining cash from an automatic teller machine as well as diverse applications such as controlling access to a building and loyalty card operations. 
   Be this as it may, to carry out the transaction, this kind of contact-free microcircuit card cooperates with a unit referred to hereinafter as a “receiver”. 
   Compared to contact microcircuit cards, contact-free microcircuit cards have the advantage of not necessitating physical insertion of the card into the receiver, as a transaction can be carried out when the contact-free card is within a sufficiently small distance of the receiver. 
   Prior art contact-free microcircuit cards are conventionally used to carry out transactions that do not necessitate identification of the card user by intentionally entering a personal identification number (PIN). This is because this step is not generally necessary for the usual uses of contact-free cards, such as controlling access to a building, for example. 
   However, in the case of a multiple application card, it may be beneficial to secure certain applications by intentionally entering a personal identification number. 
   In the case of using a contact card in the manner known in the art, in particular for withdrawing cash, this intentional identification step is carried out by entering a personal identification number on a keypad incorporated in the receiver. 
   In the case of using a contact-free microcircuit card, the solution consisting in entering this information by means of a keypad incorporated into the receiver is not satisfactory, for a number of reasons. 
   First of all, this kind of use necessitates intervention of the user at the receiver, which may be a problem in certain applications. 
   Also, in the case of transactions necessitating a very high level of security, a user may hesitate to enter his personal identification number into a receiver because he is afraid of the number being pirated. 
   SUMMARY OF THE INVENTION 
   The present invention enables secure electronic transactions to be carried out with a contact-free electronic card that avoids the problems previously cited. 
   To be more precise, a first aspect of the present invention provides a contact-free microcircuit card used in conjunction with a receiver to carry out an electronic transaction, characterized in that it incorporates a keypad for entering information used in said transaction. 
   This kind of microcircuit card, providing for the entry of information by the user by means of the keypad incorporated into the card, avoids the use of the keypad of the receiver and solves the two problems previously cited. 
   According to one advantageous feature of the microcircuit card, this card includes means adapted to authorize execution of said transaction after validation of a code entered by means of said keypad. 
   It is thus possible, in the case of a commercial transaction in particular, to enter a personal identification number on the card, which makes it very difficult to pirate the number. 
   Of course, the keypad on the card may be used to enter any other type of information. 
   According to another particular feature of the card according to the invention, it comprises a communication antenna enabling said transaction with said receiver, the card being supplied with electrical power at least in part by an induced current received by said antenna and generated by an electromagnetic field generated by said receiver. 
   This feature is particularly advantageous as it yields a very high security level. This is because the card is supplied with power by an electromagnetic field generated by the receiver and cannot be used as it exits the field if it is moved away from the receiver, for example by a few meters. 
   In another embodiment, the card includes means for resetting it if communication with said receiver is interrupted for at least a predetermined time period. 
   This embodiment also makes this kind of card more secure to use and may advantageously be employed if the card is supplied with power autonomously, namely by an extra-thin battery or a solar cell, for example. 
   According to another feature, the card according to the invention further comprises a screen for checking information entered by means of said keypad. 
   Of course, this screen may also be used to display information transmitted to the card by the server or any other information that is useful for the transaction. 
   A second aspect of the present invention provides a process of fabricating a microcircuit card as described briefly hereinabove, the card including a communication antenna allowing said transaction with said receiver. 
   The fabrication process includes a step of screenprinting in at least one layer producing simultaneously at least one portion of the connection circuit of said keypad and at least one portion of said antenna. Such a process is particularly advantageous in that it makes it possible to reduce the number of stages of fabrication. 
   This fabrication process allows easy adaptation of a keypad to a conventional contact-free microcircuit card. 
   According to one particular feature of the fabrication process, the screenprinting step comprises:
         applying a first conductive layer for producing a first portion of the connection circuit of the keypad and a first portion of said antenna,   placing electrically insulative material bridges over regions of said first portions produced during the application of said first conductive layer, and   applying a second conductive layer for completing said connection circuit of the keypad and said antenna, the second conductive layer being insulated from the first conductive layer by means of said insulative material bridges.       

   The step of placing electrically insulative material bridges between the two steps of applying the conductive layer enables fabrication by screenprinting of relatively complex two-stage circuits. 
   A third aspect of the invention provides a method of electronic transaction between a microcircuit card as briefly described hereinabove and a receiver, said method includes the following steps:
         user authentication means incorporated in said card verifying the validity of a code entered by means of said keypad, and   authorizing said transaction as a function of the result of said verification step.       

   The particular advantages and features specific to this method are identical to those of the microcircuit card of the invention and are not repeated here. 
   A preferred embodiment of the electronic transaction method according to the invention includes, before said verification step, a step of selecting a secure mode of use of said card as a function of said transaction. 
   By virtue of this particularly advantageous feature, the contact-free microcircuit card may be used both for secure transactions involving entry of information on the keypad and for transactions that necessitate no such entry. The card is then referred to as a “multiple application card”. 
   Finally, the invention is directed to use of a microcircuit card as described briefly hereinabove in cooperation with a receiver connected to the Internet to carry out a secure electronic transaction on the Internet between said receiver and another unit also connected to the Internet. 
   This kind of use provides for electronic transactions on the Internet that are very secure because the user&#39;s personal identification number is entered on the card and is not transmitted to the receiver. 

   
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
     Other aspects and advantages of the present invention will become more clearly apparent in the light of the following description of particular embodiments, the description being given by way of nonlimiting example only and with reference to the appended drawings, in which: 
       FIG. 1  represents an external face of a microcircuit card of the invention; 
       FIG. 2  represents the internal structure of the microcircuit card of  FIG. 1 ; 
       FIGS. 3   a  and  3   b  represent the state of the microcircuit card of the invention after intermediate steps of a method of fabricating a microcircuit card of the invention; 
       FIG. 4  represents the use of a microcircuit card of the invention to carry out a transaction with a receiver connected to the Internet; and 
       FIG. 5  represents the main steps of an electronic transaction method using a microcircuit card of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  represents a contact-free microcircuit card  10  according to the present invention. 
   The main steps of a method of fabricating a microcircuit  10  according to the invention are described next with reference to  FIG. 1 . 
   The microcircuit card  10  may be used to carry out different types of electronic transaction. 
   In accordance with the present invention, the microcircuit card incorporates a keypad  12  used during the transaction to enter information. 
   In the preferred embodiment, the keypad  12  includes keys for entering digits, a key  12   a  for resetting the information entered by means of the keypad  12 , and a validation key  12   b.    
   In another embodiment, not shown, the keypad  12  also includes keys for entering character strings, for example. 
   The microcircuit card  10  further comprises a screen  14  for checking the information entered by means of the keypad  12 . 
     FIG. 2  represents the internal structure of the microcircuit card  10  represented in  FIG. 1 . 
   The main steps of a process for fabricating a microcircuit card  10  according to the invention are described next with reference to  FIG. 2 . 
   The microcircuit card  10  includes a printed circuit  20  to which are fixed microswitches  22   a  facing the keys of the keypad  12 . 
   The microswitches  22   a  are connected by a connection circuit  26  to a microcircuit  24 . 
   In a manner that is known in the art, the microcircuit  24  comprises processing means consisting of a microprocessor and registers adapted in particular to store instructions of a computer program, for example. 
   In a preferred embodiment, the microprocessor is adapted, when it executes the instructions of the program, to validate a code entered by means of the keypad  12  and to authorize the execution of a transaction after validation of the code. 
   The card  10  also includes an antenna  28  connected to the microcircuit  24 . 
   The main steps of a method for fabricating a microcircuit card  10  according to the invention are described next with reference to  FIGS. 3   a  and  3   b.    
   A preferred embodiment of the fabrication method includes a screenprinting step for simultaneously producing at least one portion of the connection circuit  28  of the keypad  12  and at least one portion of the antenna  28 . 
   To be more precise, this screenprinting step includes the application of a first conductive layer for producing a portion  26   a  of the connection circuit  26  of the keypad  12  and a first portion  28   a  of the antenna  28 . 
   The screenprinting technique for applying a conductive layer to an electronic card is not described here because it is well known to the person skilled in the art. 
   In the fabrication method of the invention, after applying the first layer, electrically insulative material bridges  30  are placed over regions of the first portions  26   a ,  28   a  of the connection circuit  26  and the antenna  28 , respectively, produced by the application of the first conductive layer. 
   This step of placing the insulative material bridges  30  yields the microcircuit card  10  represented in  FIG. 3   b.    
   The fabrication method for the microcircuit card  10  then includes the application of a second conductive layer to complete the connection circuit  26  of the keypad  12  and the antenna  28 . 
   The second conductive layer is insulated from the first conductive layer by the insulative material bridges to prevent short circuits. 
   This kind of screenprinting is also used to produce an antenna with multiple turns running around the entire perimeter of the card  20 . 
   The application of the second conductive layer terminates the screenprinting step and yields the microcircuit card  10  represented in  FIG. 2 . 
   The use of a microcircuit card  10  to carry out a transaction with a receiver  40  connected to the Internet is described next with reference to  FIG. 4 . 
   In the preferred embodiment described here, the receiver  40  includes means  42  for generating an electromagnetic field E. 
   When the card  10  is in the magnetic field E, the antenna  28  picks up a portion of this electromagnetic energy and generates an induced current for supplying electrical power to the microcircuit  24 . 
   In a preferred embodiment, this electromagnetic field E is the only source of power for the microcircuit card  10 . 
   Accordingly, the microcircuit  24  is no longer supplied with power if the microcircuit card  10  leaves the electromagnetic field E, which provides very effective protection of the microcircuit card  10  against fraudulent use. 
   The main steps of an electronic transaction method between the microcircuit card  10  and a unit  50  connected to the Internet are described next with reference to  FIG. 5 . 
   As previously described, the microcircuit card  10  is not supplied with power if the card is not in the electromagnetic field E generated by the receiver  40 . 
   When the card enters the electromagnetic field E, the microcircuit  24  is supplied with power and the result of a power supply test step E 100  becomes positive. 
   That step is then followed by a test E 150  for selecting a secure mode of use as a function of the transaction. 
   If the transaction does not require a level of security necessitating the entry of a personal identification number by means of the keypad  12 , the result of the test E 150  is negative. 
   This test is then followed, during the step E 170 , by the transaction proper, after which the method terminates. 
   On the other hand, if the transaction necessitates the entry of a personal identification number by means of the keypad  12 , the result of the test E 150  is positive. 
   This test is then followed by a test E 200  to verify the validity of a number entered by the card user by means of the keypad  12 . 
   In one embodiment, this verification step E 200  consists in comparing the number entered with a number stored in registers of the microcircuit  24 . 
   In a variant, the user can make more than one attempt to enter a valid number. 
   If no valid number has been entered after these attempts, the transaction method according to the invention terminates. 
   On the other hand, as soon as a valid number is entered, the result of the test E 200  becomes positive. 
   The identification test E 200  is then followed by a step E 300  during which the secure transaction proper starts. 
   This transaction may be of different types, depending on the type of unit  50  connected to the Internet. It may be a commercial transaction, for example, if the microcircuit card  10  is a payment card. 
   The step of starting the secure transaction E 300  is followed by a test E 400  to verify if the transaction has been interrupted. 
   In this example the transaction is considered to have been interrupted:
         if the transaction has terminated normally, or   if the card  10  leaves the electromagnetic field E, or   if communication between the receiver and the card is interrupted for at least a predetermined time period. In practice, as soon as the microcircuit  24  receives data from the receiver  40 , it resets a counter (not shown). If the content of this counter exceeds a value representing this predetermined time period, the result of the test E 400  becomes positive.       

   This test is then followed by a step E 500  during which the microcircuit  24  resets the microcircuit card  10 . 
   This constitutes an additional security feature to combat fraudulent use of the microcircuit card  10 , especially if the card is at least partly supplied with power by a power source other than the electromagnetic field E previously described. 
   The step E 500  of resetting the card  10  terminates the transaction method according to the invention.