JP2015106331A - Dual ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct wires formed on a front side and a rear side of an antenna sheet without using means such as a through hole or caulking.SOLUTION: In an IC card of the present invention, all wires including a second coupling coil and an antenna coil formed on an antenna sheet base material are formed at least partially on a first side of the antenna sheet base material and a second opposite side interposing the antenna sheet base material therebetween, respectively. In each of the wires formed on the first side and the second side, at least one or more parts thereof are formed as a capacitor, and the wire formed on the first side and the wire formed on the second side are conducted via the capacitor.

Description

  The present invention is a contact type that receives power supply power, exchanges signals via electrical contacts, etc., and power supply power reception, signal exchanges, etc., without contact by an electromagnetic coupling method without providing electrical contacts on an IC card. The present invention relates to a dual IC card that functions as both a non-contact type performed in the above.

  As an IC card incorporating a semiconductor memory or the like, a dual IC card that functions as both a contact type and a non-contact type is known. As such a dual IC card, an antenna coil provided inside the card for non-contact communication with an external terminal and an IC module functioning as both a contact type and a non-contact type are physically connected by wiring. There is a so-called physical coupling type dual IC card. (For example, Patent Document 1)

  Such a mounting method is relatively simple, but it is difficult to confirm the state of the connection portion between the IC module and the antenna, and the connection reliability becomes a problem. Further, the connection portion is likely to deteriorate due to mechanical stress. In addition, a conductive adhesive coating process and thermocompression bonding process are required to connect the IC module and antenna, making it difficult to use conventional IC card manufacturing equipment with external terminals and installing a new manufacturing line. There must be.

  On the other hand, a first coupling coil is formed in an IC module that functions as both a contact type and a non-contact type, and a second coupling coil for electrically coupling to the coil formed in the IC module in a non-contact manner. In addition, there is a so-called electromagnetic coupling type dual IC card in which an antenna coil for non-contact communication with an external terminal is provided in the card. In such a dual IC card, the first coupling coil and the second coupling coil are arranged so as to be tightly coupled to each other, thereby enabling non-contact signal transmission to the IC module by transformer coupling. The thing is proposed (for example, patent document 2). The electromagnetic coupling type dual IC card is not required to physically connect the IC module and the antenna coil by wiring, and problems such as poor contact are less likely to occur.

JP 2000-182017 A JP-A-11-149538

  The electromagnetic coupling type dual IC card as in the above example needs to have an antenna coil and a second coupling coil for electromagnetically coupling with the IC module on the antenna sheet substrate. For this reason, as shown in FIG. 6, there is a case where a part of the wiring has a structure intersecting when viewed from above. In such a case, it may be possible to take several configurations.For example, the wiring is divided into a first surface of the antenna sheet base material and a second surface on the opposite side of the antenna sheet base material. A closed loop circuit can be formed by forming on a plurality of surfaces.

  In such a case, the electrical connection between the wiring formed on the first surface and the wiring formed on the second surface is usually performed mainly by forming a through hole or caulking. Has been done. However, these methods have problems such as high processing costs and slightly low connection reliability.

  The present invention has been made in view of the above problems, and in the electromagnetic coupling type dual IC card, when the wiring forming the antenna coil and the second coupling coil is formed separately on a plurality of surfaces, each surface It is an object of the present invention to provide a dual IC card which can be connected between wirings formed on the board by means of low cost and connection reliability without using means such as through holes and caulking.

In order to achieve the above object, the invention described in claim 1
An IC module having at least an IC chip having a non-contact communication function and a first coupling coil;
An antenna sheet having a second coupling coil, an antenna coil, and an antenna base substrate;
An IC card comprising:
Of all the wirings including the second coupling coil and the antenna coil formed on the antenna sheet base material, at least a part thereof is the first surface of the antenna sheet base material and the antenna sheet. Each of the wirings formed on the second surface on the opposite side across the base material, and each of the wirings formed on the first surface and the second surface has at least one location as a capacitor The IC card is characterized in that the wiring formed and formed on the first surface and the wiring formed on the second surface are conducted through the capacitor.

  The invention according to claim 2 is characterized in that a part of at least one of the second coupling coil and the antenna coil is formed as the capacitor. It is a thing.

  The invention according to claim 3 is the IC card according to claim 1 or 2, wherein the surface is embossed, and the embossing is performed when the IC card is viewed from above. The IC card is characterized in that the area and the area where the capacitor is formed do not overlap.

  The invention according to claim 4 is the IC card according to claims 1 to 3, wherein the inductance of the second coupling coil and the inductance of the antenna coil are added in series, and the capacitor The capacitance is an IC card characterized in that the IC module resonates at a frequency substantially equal to the frequency of the electromagnetic wave used for non-contact communication.

  In the IC card according to claim 1, the wiring forming the antenna coil and the second coupling coil is arranged on the first surface on the antenna sheet substrate and the second surface on the opposite side across the antenna sheet substrate. In the case of forming each separately, since electricity flows through the capacitor by forming one or more locations on the wiring as a capacitor, it is necessary to process through holes or caulking, which was necessary in the past. In addition, the manufacturing cost can be reduced and a highly reliable connection is possible.

  In the IC card according to the second aspect, the capacitor is provided in a form that forms a part of the antenna coil or the second coupling coil itself, so that the capacitor portion simultaneously functions as a coil. Therefore, the wiring installation area on the antenna sheet substrate can be reduced.

  Further, the IC card according to claim 3 is embossed by not placing a capacitor in advance under the area to be embossed when embossing the card surface after the card molding. Therefore, it is possible to suppress the appearance and functional defects of the IC card.

Further, the IC card according to claim 4 is caused by the received electromagnetic wave by making the resonance frequency of the closed loop circuit formed by the wiring and the capacitor on the antenna sheet base material substantially the same as the frequency of the received electromagnetic wave. It is possible to reduce the attenuation over time of the induced current generated as a result. When there are a plurality of capacitors in the circuit, the combined capacitance of all the capacitors connected in series on the closed loop can be considered as the capacitance of the capacitor in this circuit.

It is an equivalent circuit diagram of the non-contact coupling circuit explaining the principle of the non-contact transmission mechanism of the present invention. It is sectional drawing which shows an example of a structure of the IC card which becomes this invention. It is sectional drawing which shows an example of a structure of the IC module which becomes this invention. It is a top view which shows an example of the wiring in the IC card which becomes this invention. It is a series of figures which show an example of the manufacturing process of the IC card which becomes this invention. It is a top view which shows an example of the wiring in the conventional IC card.

  The IC card according to the present invention will be described below with reference to the drawings as necessary.

First, the basic configuration and basic principle of the non-contact transmission mechanism of the IC card according to the present invention will be described. FIG. 1 is an equivalent circuit diagram showing an example of a non-contact coupling circuit for explaining the principle of the non-contact transmission mechanism of the present invention. A transmission / reception circuit of a non-contact type external read / write device (not shown) is connected to a transmission / reception coil which is an electromagnetic coupler for supplying power to and transmitting information to the non-contact transmission mechanism of the dual IC card.

The non-contact transmission mechanism of the dual IC card includes an antenna coil 32 that is directly electromagnetically coupled to a transmission / reception antenna of an external read / write device and is involved in power reception and information transfer, and a dual IC chip mounted on the dual IC module 2 1 and a first coupling coil 23 connected to the first coupling coil 23, and a second coupling coil 33 that is tightly coupled to transmit the signal received by the antenna coil 32 to the first coupling coil 23 with maximum efficiency. If the line capacitance of the coil is not sufficient, a capacitive element can be arranged in the circuit as necessary.

In the case where power and information are transmitted from the external read / write device to the dual IC card, the coupling of each coil will be described below. A high frequency magnetic field is induced in the transmission / reception coil by a high frequency signal (not shown) generated in the transmission / reception circuit of the external read / write device. This high frequency signal is radiated into space as magnetic energy.

At this time, when the dual IC card is positioned in the high frequency magnetic field, a current is induced in the resonance circuit including the antenna coil 32 having the dual IC strength by the high frequency magnetic field generated by the transmission / reception coil of the external read / write device. At this time, a current due to a high-frequency magnetic field is also induced in the first coupling coil 23 and the second coupling coil 33 on the dual IC card, but since the amount induced by the antenna coil 32 is smaller by one digit or more, it is received. The sensitivity greatly depends on the characteristics of the antenna coil 32.

A signal received by the resonance circuit including the antenna coil 32 is transmitted to the second coupling coil 33. After that, since the second coupling coil 33 and the first coupling coil 23 are arranged in a tightly coupled manner that exhibits the maximum transmission efficiency, the dual IC chip 1 is connected to the dual IC chip 1 by the transformer coupling between the second coupling coil 33 and the first coupling coil 23. A signal is transmitted. The maximum transmission efficiency of transformer coupling between the second coupling coil 33 and the first coupling coil 23 is determined by the selection of circuit constants. As described above, the reception characteristics are improved.

  Hereinafter, the configuration of the IC card according to the present invention will be described with reference to the drawings as necessary.

  An example of the IC card according to the present invention is shown in FIG. The IC card shown in FIG. 2 includes an IC chip 1, an IC module 2 including the IC chip 1, an antenna sheet (IC inlet) 3, and an oversheet 4. Each member constituting the IC card can be manufactured separately, and each member may be prepared in advance and then integrated as an IC card. By adopting this configuration, each member can be manufactured. It is possible to make the quality characteristics of a certain level or more in advance.

  In addition, although the example shown in FIG. 2 has a three-layer configuration in which the antenna sheet 3 is sandwiched between two oversheets 4, the base material configuration of the IC card according to the present invention is not limited to three layers, It is preferable to adopt an appropriate configuration in accordance with the function or manufacturing method. For example, a new layer having another function may be provided, or an oversheet or an antenna sheet 3 may be further laminated. In the example shown in FIG. 2, the side surface of the antenna sheet 3 is exposed, but the oversheet 4 can be made larger than the antenna sheet 3 to cover the side surface portion of the antenna sheet 3. Good. Further, in the example shown in FIG. 2, a configuration is described in which a part of the antenna sheet 3 is punched and the IC module 2 is inserted into the punched portion. For example, the oversheet 4 is adjusted to be thicker or the antenna sheet is In the case where 3 is arranged at a position farther from the surface where the IC module 2 is inserted, the antenna sheet 3 does not necessarily have to be punched out.

  The IC chip 1 only needs to be an IC chip having at least a non-contact communication function, and of course, its processing capability, function, etc. are not limited at all. In the following, the present invention will be described by taking as an example a configuration in which an IC chip having both a contact communication function and a non-contact communication function is used. The IC chip is not necessarily compatible with contact-type communication, and the present invention has a configuration that does not support contact-type communication. It does not prevent you from being adapted.

  An example of the configuration of the IC module 2 will be described with reference to FIG. The IC module 2 shown in FIG. 3 includes an IC chip 1, a module substrate 21, an external connection terminal 22 (terminal electrode), and a first coupling coil 23. The module substrate 21 is only required to be insulative and have a certain heat resistance. For example, polyimide having a thickness of about 50 μm to 200 μm, glass epoxy (epoxy resin impregnated glass fiber laminate), or the like can be used. .

  The IC chip 1 is preferably installed on a different surface from the external connection terminal 22 on the module substrate 21. Further, the connection between the IC chip 1 and the external connection terminal 22 can be physically connected by making a hole in the module substrate 21 or by a method such as wire-bonding. Reference numeral 22 denotes a filled via and a wiring layer, which are electrically connected to the electrodes of the IC chip 1. Further, the IC chip 1 can be protected with a sealing agent 24 such as an epoxy resin as required.

  The external connection terminal 22 can be formed by attaching a conductive metal foil to the surface of the module substrate 21 and then performing an etching process or pattern printing by screen printing or the like. As the conductive metal, for example, aluminum or copper having excellent conductivity is used. Further, one or more platings of nickel, copper, gold, etc. can be applied on the formed pattern in accordance with various purposes such as contact resistance reduction. For example, when nickel plating and gold plating are performed on a copper foil pattern, the nickel plating is formed with a thickness of about 0.5 μm to 3 μm, and a thickness of about 0.01 μm to 0.3 μm is formed thereon. Gold plating can be formed.

  The first coupling coil 23 is preferably formed on the module substrate 21 and on a different surface from the surface on which the external connection terminals 22 are formed. The first coupling coil 23 may be formed in the same procedure as the formation of the external connection terminal 22, or a winding coil wound with a conductive wire coated with insulation or a coil printed with conductive ink may be used. it can.

  An example of the antenna sheet 3 according to the present invention is shown in FIG. The antenna sheet 3 shown in FIG. 4 includes an antenna sheet base material 31, an antenna coil 32, and a second coupling coil 33. The antenna sheet base material 31 only needs to have insulation and a certain degree of flexibility and strength. For example, polyimide resin, polyethylene terephthalate resin, polyethylene naphthalate resin, polyvinyl chloride resin, polypropylene resin, polycarbonate resin Acrylic resin, polystyrene resin, ABS resin, polyamide resin, polyacetal resin, and the like can be used. The thickness of the antenna sheet base 31 is generally set between about 15 μm and 200 μm.

  The wiring including the antenna coil 32 and the second coupling coil 33 is patterned by performing an etching process after laminating a conductive metal foil such as aluminum or copper on the antenna sheet substrate 31; Or you may form by carrying out pattern printing by screen printing etc., and you may give one or more plating, such as copper, nickel, gold | metal | money, tin, and solder, on it as needed. Alternatively, a coil wound with a conductive wire coated with an insulating coating or a coil printed with conductive ink can be used. The thickness of the wiring is generally set between about 5 μm and 50 μm.

  As shown in FIG. 4, the wiring including the antenna coil 32 and the second coupling coil 33 according to the present invention has at least a part of the first surface of the antenna sheet base 31 and the antenna sheet base 31. It is formed on the second surface on the opposite side of the sandwich. Further, at least one of the wirings formed on the first surface and the second surface is formed as a capacitor 34. The capacitor 34 may be formed only at one end as shown in FIG. 4 (a), or both ends thereof are used as the capacitor 34 as shown in FIGS. 4 (b), (c), and (d). It may be formed. When the capacitor 34 is formed, it is preferable to form the capacitor 34 as a part of the antenna coil 32 and the second coupling coil 33 as shown in FIGS. Further, the second coupling coil 33 may be arranged outside the antenna coil 32 as shown in FIGS. 4A, 4B, and 4C, or may be arranged inside the antenna coil 32 as shown in FIG. 4D. May be. Further, the antenna sheet 3 can be punched out at a site where the wiring is not formed.

  In the above illustrated example, the case where there is one wiring formed on each of the first surface and the second surface is described. However, two wires are provided on any one surface. It goes without saying that the present invention can also be applied to the case where the above independent wiring is formed. In the above illustrated example, the case where the wiring pattern is formed on both surfaces of one antenna sheet base material is described. However, when the antenna sheet has a multilayer structure, the number of layers in which wiring can be formed increases. Therefore, it is possible to provide wiring for each layer, and in this case, the present invention can naturally be applied to establish conduction between the layers. Furthermore, in the above illustrated example, the example in which the wiring formed on the antenna sheet substrate 31 is a series circuit has been described, but the wiring may be a parallel circuit.

  The line width, thickness, number of turns of the coil of the antenna coil 32 and the second coupling coil 33, the area, shape, etc. of the capacitor 34 can be set as appropriate according to restrictions due to arrangement and characteristics. When each coil and capacitor 34 are formed such that the resonance frequency of the closed loop circuit formed by the wiring on 31 and the capacitor 34 is substantially the same as the frequency of the received electromagnetic wave, the induced current generated due to the received electromagnetic wave is reduced. It is preferable because attenuation can be suppressed. The frequency to be received is not limited as long as it is a frequency in a band used in non-contact communication. For example, the 13.56 MHz band is used.

  As for the capacitor, it is not always easy to unambiguously define the boundary between the capacitor and the non-capacitor by its physical shape or material. If the metal plates formed on both the first surface and the second surface are conductive to the extent that they can perform the non-contact communication function required for the IC card according to the present invention, they are regarded as capacitors. To do.

  As the oversheet 4, it is possible to use a general material used for a card base or the like. For example, polyvinyl chloride resin, amorphous polyethylene terephthalate copolymer (PET-G), polycarbonate resin, or the like can be used. . Moreover, the surface of the card outside of the oversheet 4 may be formed with characters, designs, etc. as necessary.

  Next, an example of the manufacturing process of the IC card 1 according to the present invention will be described with reference to FIG. In addition, the example given below is only one example, and in assembly, any member may be adjusted first, and any member may be joined first, and the order thereof is not limited. .

  First, two base materials 41 made of PET-G or polyvinyl chloride are prepared. At this time, the oversheet 4 may be printed with an image pattern 42 such as a character or a picture on one or a plurality of surfaces by offset printing, screen printing, or the like.

  Subsequently, the antenna sheet 32 and the second coupling coil 33 are formed by laminating a metal foil such as copper on the antenna sheet substrate 31 and performing etching, or by screen printing or the like. Adjust (FIG. 5A). Next, the oversheet 4 is laminated on both surfaces of the antenna sheet 3 via the adhesive 5, and the IC card base 6 is formed by hot pressing (thermal lamination) at a predetermined temperature and pressure (see FIG. 5 (b)). Examples of the adhesive include ethylene vinyl alcohol (EVA), polyester, polyurethane, acrylic single-piece or mixed hot-melt sheet-type adhesive, two-component reactive epoxy resin, urethane resin, UV and cationic polymerization, anaerobic In addition, a resin that is completely cured by combined curing of moisture or the like, or a mixture thereof can be used. The adhesive 5 may be coated on the oversheet 4 or the antenna sheet 3 in advance as an adhesive resin layer.

  At this time, when the IC card base 6 is manufactured by applying the sheet to a single sheet, the IC card base 6 is punched into a predetermined card size by a puncher to form a piece of individual card. To form.

Next, a predetermined position of the IC card base 6 is counterbored (milled) to form a recess 61 for mounting the IC module 2 (FIG. 5C). The recess 61 is mainly formed inside the second coupling coil 33. At this time, there is a risk that the wiring constituting the second coupling coil 33 may be broken due to the influence of the stress caused by the processing. Therefore, in the wiring constituting the second coupling coil 33, particularly the portion close to the inside may be configured thicker than the other portions,
For example, the thickness can be about 1.25 to 1.5 times.

  Next, a double-sided copper-clad laminate in which copper foil is laminated on both sides of the module base material 21 such as glass epoxy and polyimide is subjected to patterning processing and via processing processing by a photo-etching process or the like, and external connection on the module base material 21 The terminal 22 is formed. The external connection terminal 22 may be subjected to nickel, gold plating, or the like. Further, the IC chip 1 is installed on the module base 21 to prepare the IC module 2 (FIG. 5D). The IC chip 1 and the module base 21 can be connected by a method such as wire-bonding or flip-chip connection. The external connection terminals 22 are connected to the electrodes of the IC chip 1 by filled vias and wiring layers. Are electrically connected to each other. The IC chip 1 is preferably protected with a sealing agent 24 such as an epoxy resin.

  Next, the IC module 2 is aligned and mounted in the recess 61 provided on the IC card base 6, and the IC module 2 is embedded and fixed in the recess by hot pressing, so that the dual IC card according to the present invention can be obtained. Is obtained (FIG. 5 (e)).

  Although not shown, the dual IC card according to the present invention can be magnetically striped or embossed on the surface. The region where the magnetic stripe is formed and the region where the embossing is performed are preferably arranged so as not to overlap with the wiring including the antenna coil, the second coupling coil, and the capacitor when viewed from the upper surface of the card.

  Thus, in the IC card according to the present invention, the wiring formed on the first surface and the second surface on the antenna sheet substrate is not subjected to processing such as through-holes and caulking, and the like through the capacitor. Since it conducts, it is possible to reduce the cost associated with the previous processing step and to obtain high connection reliability.

DESCRIPTION OF SYMBOLS 1 ... IC chip 2 ... IC module 21 ... Module base material 22 ... External connection terminal 23 ... 1st coupling coil 24 ... Sealing material 3 ... Antenna sheet 31 ... Antenna sheet base material 32 ... ... Antenna coil 33 ... Second coupling coil 34 ... Capacitor 4 ... Over sheet 41 ... Over sheet base material 42 ... Image pattern 5 ... Adhesive 6 ... IC card base 61 ... Recess

Claims (4)

An IC module having at least an IC chip having a non-contact communication function and a first coupling coil;
An antenna sheet having a second coupling coil, an antenna coil, and an antenna base substrate;
An IC card comprising:
Of all the wirings including the second coupling coil and the antenna coil formed on the antenna sheet base material, at least a part thereof is the first surface of the antenna sheet base material and the antenna sheet. Each of the wirings formed on the second surface on the opposite side across the base material, and each of the wirings formed on the first surface and the second surface has at least one location as a capacitor An IC card, wherein the formed wiring formed on the first surface and the wiring formed on the second surface are conducted through the capacitor.   2. The IC card according to claim 1, wherein a part of at least one of the second coupling coil and the antenna coil is formed as the capacitor.   The IC card according to claim 1 or 2, wherein the surface is embossed, and when the IC card is viewed from above, an embossed region and a region where a capacitor is formed are provided. An IC card that does not overlap.   4. The IC card according to claim 1, wherein an inductance obtained by adding the inductance of the second coupling coil and the inductance of the antenna coil in series and the capacitance of the capacitor are in contactless communication with the IC module. An IC card characterized by resonating at a frequency substantially equal to the frequency of the electromagnetic wave used to perform the operation.