JP2000235635A - Capacitor built-in non-contact type ic card and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact type IC card whose resonance circuit has a capacity-adjustable capacitor and to provide its manufacturing method. SOLUTION: In this capacitor built-in non-contact type IC card provided with a resonance circuit consisting of an antenna coil 13 and a planar capacitor 15 in a card substrate wherein the capacitor capacity in the resonance circuit is adjustable, the capacitor has a configuration composed of branched linear pattern groups and the capacitor capacity can be adjusted by disconnecting a linear pattern from the branched part. The capacitor of such a non-contact type IC card can be manufactured by simultaneously forming a fine line capacitor pattern, the coil 13 and antenna coil connection terminals 141 and 142 on an antenna substrate 121A, covering the capacitor pattern with an insulating layer and further providing a conductive plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type IC card which performs non-contact communication by electromagnetic induction or an IC card having both functions of a contact type and a non-contact type IC card, wherein an antenna coil is provided on a base. The present invention relates to a non-contact type IC card having a built-in capacitor and a planar capacitor and capable of adjusting a resonance frequency to a predetermined value within a certain range, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In an IC card having a function of performing non-contact communication by electromagnetic induction, a resonance frequency is adjusted to a predetermined value by incorporating a capacitor in an antenna substrate having an antenna coil. Conventionally, the following types of IC cards of this type are known. A card made by mounting a ceramic capacitor on an antenna substrate and then laminating it. A card manufactured by forming a capacitor by performing double-sided etching on an antenna substrate, adjusting the capacitor capacity after mounting an IC chip, and then laminating. A card manufactured by performing a double-sided etching on an antenna substrate to form a capacitor, adjusting the capacitor capacity, mounting an LSI, and laminating.

However, in the IC card of the above embodiment,
Each has the following problems. I with a ceramic capacitor mounted on an antenna substrate
With the C card, the capacity of the capacitor cannot be adjusted. It is not suitable for cards due to the large size of the capacitor.
Since the number of components to be mounted is increased, the cost is increased in terms of processes and materials. In an IC card that forms a capacitor by etching both sides of the antenna substrate and adjusts the capacitor capacity after mounting the IC chip, the thickness of the dielectric sheet changes thinly due to the pressing pressure during lamination with other sheets. Changes (increases). The dielectric constant of the sheet laminated on top and bottom also affects the capacitor capacity. After the card processing, the capacitance of the capacitor also changes when printing or transferring a face photograph, a hologram, a sign panel, or the like. After a capacitor is formed by performing double-sided etching on the antenna substrate and adjusting the capacitor capacity, in an IC card on which an LSI is mounted, the capacitor capacity changes (increases) due to the dielectric constant of the laminated sheet after lamination.
Therefore, there is a problem that it is necessary to perform lot management for all sheets including the LSI and the etching sheet.

[0004]

Therefore, in the present invention,
In a non-contact type IC card having a terminal board or a non-contact type IC card having both functions of a contact type and a non-contact type IC card, when a concave portion for mounting an IC module is formed on an antenna substrate, one side of a capacitor pattern is simultaneously formed. An object of the present invention is to provide an IC card capable of adjusting a capacitor capacity by cutting a part and a method for manufacturing the same.

[0005]

According to a first aspect of the present invention, there is provided a card body having a resonance circuit composed of an antenna coil and a planar capacitor, and a capacitor in the resonance circuit. In a non-contact type IC card whose capacity is adjustable, the capacitor has a configuration composed of a group of branched linear patterns, and the capacitor capacity can be adjusted by cutting the linear pattern from the branch portion. A contactless IC card with a built-in capacitor. Such non-contact type IC
Since it is a card, the capacitance of the capacitor can be easily adjusted.

A second aspect of the present invention for solving the above problem is that a resonance circuit including an antenna coil and a planar capacitor is provided in a card base, and the capacitance of the resonance circuit in the resonance circuit can be adjusted. In the non-contact type IC card, the capacitor has a configuration including a group of linear patterns branched from an antenna coil connection terminal facing the concave portion for mounting the IC module, and the outer peripheral groove around the concave portion for mounting the IC module is cut. Sometimes, the non-contact IC card with a built-in capacitor is characterized in that the capacitor capacity can be adjusted by cutting the linear pattern from the branch portion. Since the contactless IC card is used, the capacitance of the capacitor can be easily adjusted.

A third aspect of the present invention for solving the above problems is a non-contact type in which a resonance circuit including an antenna coil and a planar capacitor is provided in a card base and the capacitance of the resonance circuit in the resonance circuit is adjustable. Forming a planar capacitor element comprising a group of linear patterns connected to an antenna coil, an antenna coil connection terminal, and an antenna coil connection terminal on a base material, thereby forming an antenna substrate. A step of coating the planar capacitor element with an insulating layer, and then covering the flat conductive plate to complete the capacitor, and a step of laminating another substrate on the antenna substrate to form a card substrate When,
A step of cutting a concave portion to a depth at which the external device connection terminal of the IC module can be mounted on the card base; and a step of cutting an outer peripheral groove around the concave portion to form a linear pattern of a capacitor branched from the antenna coil connection terminal. Cutting the branch portion to adjust the capacitance of the capacitor, and a method of manufacturing a non-contact type IC card with a built-in capacitor. Because of the method for manufacturing such a non-contact type IC card, a non-contact type IC whose capacitor capacity can be adjusted.
Cards can be easily manufactured.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A non-contact type IC card according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an embodiment of the non-contact type IC card of the present invention, and FIG.
Is an antenna substrate 121A of the non-contact type IC card shown in FIG.
FIG. The non-contact type IC card 10 with a built-in capacitor of the present invention is a non-contact type IC card having an external device connection terminal board and applied to a type in which an IC module is mounted on the card surface. Therefore, even if it is a non-contact type, it is not applied to a so-called embedded type which does not have a terminal substrate on the card surface. The terminal board may be a contact-type and non-contact-type common board for the purpose of connection with an external device, and also includes a case where the terminal board is merely a module mounting board not for the purpose of connection with the external device.

As shown in FIG. 1, in one embodiment of the non-contact type IC card of the present invention, an external device connection terminal 112 is provided on the card surface. The dashed line in the upper half on the terminal side of the card means that the antenna coil 13 and the capacitor 15 are provided buried inside the card. The antenna coil 13 may be provided along the entire outer periphery of the card.
In the embodiment, since the lower half of the card is a so-called emboss area for displaying a card user name and the like, it is provided only around the upper half of the card. Through such an antenna coil, it is possible to perform data communication with an external device in a non-contact manner or to receive a necessary power supply.

As shown in FIG. 2, the antenna substrate 121A
It is formed on a card base material that becomes a core sheet. Generally, the antenna coil 13 or the antenna coil connection terminal is formed by forming a pattern by a photo-etching technique using a glass epoxy, polyimide, or vinyl chloride base material adhered to a copper foil, or by printing a conductive ink or embedding a winding. 141 and 142 are formed. The antenna coil connection terminals 141 and 142 are formed so as to face the IC module mounting recess for connection with the IC module. The antenna coil is usually formed with a line width of about 0.1 mm and two to five turns along the outer periphery of the card. In FIG. 2, a portion denoted by reference numeral 132 is a portion to be a jumper wire. Usually, a means for conducting through the through-hole to the other conductor coil through the back surface of the substrate or providing an insulating layer to conduct is provided. Can be

The feature of the non-contact type IC card of the present invention resides in that the non-contact type IC card has a capacitor 15 which is connected to one of the antenna coil connection terminals 141 and formed in a planar pattern. Reference numeral 182 denotes a second concave portion in which the mold resin portion of the IC module is embedded.
A portion 4 is an outer peripheral groove provided for absorbing bending stress of the card, and is formed by cutting from the surface of the card to a depth which does not normally reach the antenna coil surface.

FIG. 3 is an enlarged view of the IC module mounting portion and the capacitor portion of FIG. FIG. 3A is a plan view showing the positional relationship before the IC module mounting concave portion 18 is formed on the antenna substrate 121A and the IC module is mounted. FIG. 3B shows a cross section taken along line A ₁ -A ₂ in FIG. 3A.
This shows a state in which oversheets 125 and 126 are stacked.

As shown in FIG. 3A, the capacitor 15 has a configuration in which a group of straight lines in which thin linear patterns (ten in FIG. 3) are arranged in parallel are formed on a base material in a plane. have. One end of the linear pattern branches off from one antenna coil connection terminal 141, and the other end is open without being connected. Therefore, the capacitor pattern 151 is formed as a so-called comb-shaped pattern. The branch portion between the connection terminal 141 and the capacitor pattern can be cut by cutting only the portion of the outer peripheral groove 184 to reach the antenna coil connection terminal, thereby cutting the branch portion and adjusting the capacitor capacity.
In FIG. 3, since the linear pattern is formed to have a fixed length and has the same width, each is designed to have a constant unit adjustment amount of capacitance. The length can be adjusted easily. Further, the number of straight lines is not limited to ten.

As shown in FIG. 3B, the capacitor 15
First, a comb-shaped capacitor pattern 151 is formed on the antenna substrate 121A by photoetching or the like. An insulating layer 152 formed as a thin film is provided thereon, and a conductive plate 153 is formed to cover the outermost surface in a flat plate shape. As a result, a capacitor is formed between the capacitor pattern 151 and the comb-shaped capacitor pattern 151, but a substantial capacitance is generated in a portion where the capacitor pattern 151 and the conductive plate 153 overlap. The insulating layer 152 may be formed by transferring a thin layer film or by printing using a printing method or the like, but it is necessary that the insulating layer 152 always have a constant film thickness. The conductive plate 153 may cover the comb-shaped capacitor pattern 151 in a plane, and may be provided by screen printing of conductive ink, transfer of copper foil, or the like. The conducting wire 153c from the conductive plate 153 is superimposed on the antenna coil wire connected to the antenna coil connecting terminal and printed or the like to conduct to the other antenna coil connecting terminal 142. This step of forming the insulating layer and the conductive plate can be applied to the above-mentioned portion to be the jumper wire by the same method, and if the same method is used, the trouble of forming a through hole and the like can be omitted. In FIG. 3A, the insulating layer 152 is indicated by a dashed-dotted rectangular frame, and the conductive plate 153 is indicated by a solid-line rectangular frame.

The cutting of the capacitor pattern from the antenna coil connection terminal is performed by numerically controlling the cutting drill blade so that, in FIG. By performing the cutting at a depth deeper than the portion, the required number of linear capacitor patterns 151 can be cut. Although both ends of the antenna coil 13 are connected to the antenna coil connection terminals 141 and 142, the connection to the terminal 141 is designed so as to be introduced from a direction that is not cut by a drill. Portions of the connection terminals 141 and 142 protruding into the module mounting recess 18 are portions that are removed when the recess 182 is cut.

Here, communication by electromagnetic induction will be briefly described with reference to a specific example. Generally, at least one or more AC magnetic fluxes (electromagnetic waves) are transmitted from a wireless communication device (hereinafter, referred to as a “reader / writer” or “R / W”) to an antenna circuit in a card, and a coil in the antenna circuit is formed. Interlink. This electromagnetic wave (transmitted wave) has two purposes: (1) supply of power for moving an LSI by electromagnetic induction; and (2) perform data communication using a carrier for adjustment of phase change and amplitude. At this time, there are a case where one electromagnetic wave has these two properties and a case where a plurality of electromagnetic waves have respective roles. The configuration / reply of the antenna circuit on the card side may be the same as in the case of the R / W.

In particular, paying attention to the "property of electromagnetic waves for supplying electric power", the capacitance of the parallel resonance circuit at a certain frequency is calculated using the following specific example. The antenna circuit (parallel resonance circuit) on the card side designed to resonate with the frequency of the wave transmitted by the R / W has a minimum current value and a maximum impedance. (Specific example) The transmission wave from the R / W is 13.56 MHz (I
(One frequency in the SM band). Further, in the card antenna circuit (parallel resonance circuit), the L component and the C component of the LSI, the capacitor (adjustable), and the coil (4 turns) are as shown in Table 1. Incidentally, L component of LSI and capacitor, C component C ₃ of the coil can be regarded as substantially zero or zero. (Table i) L Component C Component LSI ─── C _1: 40 pF capacitor ─── C _2: 0~10pF (adjustable 1pF units) coil 3.0μH C _3: ───

FIG. 4 is a diagram showing an equivalent circuit of the card. Here, the capacitance C of the entire circuit is the sum of the capacitance C ₁ of the LSI, the capacitance C _{2 of} the capacitor arranged in parallel, and the stray capacitance C ₃ generated at a connection portion in the circuit. (Equation 1), where C ₃ is erased assuming that it is sufficiently smaller than C ₁ and C ₂ (Equation 2). L
It is desirable that the capacitance C ₁ of the SI be smaller than the total capacitance of the circuit at the time of resonance (or at the time of “ideal frequency” described later). C = C ₁ + C ₂ + C ₃ (Equation 1) C ₃ << C ₁ , C ₃ << C ₂ , C ₁ <CC C = C ₁ + C ₂ (Equation 2) Here, the reason why the parallel circuit resonates is When the impedance Z (Equation 3) is apparently maximum, that is, when the complex number component becomes 0, the resonance frequency can be derived therefrom (Equations 4 and 5). Note that the omega _c, the angular resonant frequency, f _c denotes a resonance frequency. Z = 1 / _{[1 / R + i (ω c} C- (1 / ω c L)) ] (Equation _{3) ω c = 1 / (} LC) 1/2 = 2πf c ( Equation 4) f _c = 1 / ( 2π (LC) ^1/2 ) (Equation 5) C at this time is the capacitance of the entire circuit at the time of resonance (Equation 6). C = 1 / ((2πf) ² L) (Equation 6) When the numerical value of this example is substituted, C = 46.0 pF, and C
₂ = 6.0 pF, and a capacitor for 6.0 pF needs to be provided on the card.

In this example, the design concept of FIG. 3 expects a reduction of the capacitance of 1.0 pF by cutting one comb-shaped fine line, and there are ten thin lines of the same length and width. , 0-1
0 pF can be adjusted in units of 1.0 pF. FIG.
FIG. 9 is a diagram showing a change in the capacitance of the capacitor when the capacitor pattern is cut. In this case, as shown in the graph of FIG. 5, four of these were cut by cutting in accordance with the design values, and the remaining 6.0 pF was added to the capacitance of the LSI, and the C of the entire circuit was set to 46 pF. , 13.555 MHz, and could be adjusted to the target frequency with an error of about 5 kHz. The capacitance that can be adjusted depends on the layer configuration (distance between two electrode plates) and the material (dielectric constant of the dielectric) of the capacitor, and the adjustment unit is determined by the area of the comb-shaped pattern. The size of the comb-shaped pattern is adjusted step by step, and a combination of them can provide a capacitance of about 0.1 pF to 100 pF. Unless the capacitance of the LSI greatly varies, it is not necessary to make the adjustment range excessive.

In an actual system, it is necessary to consider the nature of waves as data communication, and the communication stability and the longest communication distance often deviate from the resonance frequency. However, it is also possible in the present invention to finely adjust the "ideal frequency" designed in the system.

When the “ideal frequency: C” in communication is determined, it is important to note that the capacity of the LSI: C ₁
Card antenna circuit capacity: a variation of the C _2. If there is no variation between the two, the effect as expected in the initial design can be expected, but in practice, the variation cannot be ignored from lot to lot or from individual differences. Therefore in the actual production, when adjusting the values of C _2, a connection terminal 141 and 142
It is desirable to perform NC processing and cut one pattern at a time step by step while measuring the capacitance between them using an impedance analyzer or the like.

In the case where the capacitance C _{1 of the} LSI has individual differences and the capacitance C ₂ of the antenna circuit also has individual differences, the following applies. COT (chip-on-tape) with LSI mounted
Punching, keep the connection mounting line on the card, connect the measuring pin to the antenna connection terminal of COT, taking by an impedance analyzer, the computer measures the C _1. The card with a built-in antenna (card base) is subjected to NC processing to expose the antenna coil connection terminal. Connect the test pins to the antenna coil connection terminal, the C ₂ measured by an impedance analyzer captures to the computer. The computer stores the “ideal capacitance”, which is the “ideal frequency”, and compares it with the sum of the data of C ₁ and C ₂ fetched in the process. calculate. A command to cut the capacitor on the card, which is sufficient to reduce the capacity, is fed back to the NC machine. After the completion, flow the line to connect the COT and the antenna. If you do not need to be aware of individual differences, determine the standard value for each lot and store it in a computer.
The above steps can be simplified and parallel processing can be performed.

FIG. 6 is a diagram showing a cross section of the concave portion for mounting an IC module. FIG. 6A shows a cross section along the line B ₁ -B ₂ in FIG. 3A, and FIG.
FIG. 6B shows a state after the IC module is mounted. As shown in FIG. 6A, the recess 1 for mounting an IC module.
Reference numeral 8 denotes a first recess 181 having a depth on which the external device connection terminal 112 of the IC module can be placed and an adhesive can be applied or laid, and a second recess having a size and depth capable of burying the mold resin 115 of the IC module. 182, a third recess 183 which is a small diameter conduction hole, and the above-described outer peripheral groove 184. As shown in FIG. 6B, when the IC module 11 is mounted, the conductive adhesive 1 is placed in the third concave portion.
9 is filled and connected to the antenna coil connection terminal 114 on the IC side, and the other parts of the IC module are adhered with the insulating adhesive 20. However, the above IC module mounting method is one embodiment, and another method can be adopted. For example, the antenna coil connection terminals 141 and 142 on the card base may be formed so as to directly appear on the step of the first concave portion, and may be connected to the IC side connection terminal without passing through the conduction hole.

Next, a method for manufacturing the non-contact IC card of the present invention will be described. FIG. 7 is a view for explaining a manufacturing process of the non-contact type IC card of the present invention. FIG. 7 illustrates the case of a four-card structure, but the card base is not limited to the four-card structure as described above.

<Formation of Antenna Substrate> First, the antenna coil 13 and the antenna coil connection terminal 1
A glass epoxy substrate in which 4 and the capacitor pattern 151 are drawn by photo-etching of copper foil, printing of conductive ink such as silver or aluminum, or a combination thereof;
An antenna substrate 121A made of a base material such as polyimide, vinyl chloride, or polyethylene terephthalate (PET) is prepared. In addition to the above, the antenna coil is formed by transferring the transfer foil on which the antenna pattern is formed to the core sheet, embedding the winding coil, and drawing while fusing the conductor with the coated resin to the base material with a weld bonder. And the like.

<Formation of Capacitor> The capacitor pattern 151 can be formed as a linear pattern of many thin wires branched from one antenna coil connection terminal 141. As an example, FIG.
As shown in the figure, ten thin lines having a uniform width and branched in a comb shape can be used, but the present invention is not limited to this example. The width and length of this thin wire are determined by the capacitance of one thin wire, but need to be determined by the unit in which the capacitance of the capacitor needs to be adjusted. For example, when adjusting in units of 1.0 pF, 0.4 to
Line length 10 mm with 0.5 mm pitch and 0.2 mm line width
In this case, the object can be almost achieved. But the capacitance is the capacitor pattern and the conductive plate 1
Not only 53 but also the dielectric constant and the thickness of the insulating layer 152 affect them, and it is necessary to sufficiently consider these factors.

Next, an insulating layer 152, which is a dielectric, is formed on the capacitor pattern 151. For this purpose, a thin insulating film can be transferred or an insulating layer can be formed by printing using an epoxy resist printing. In order to obtain stable capacitance, it is desirable that the capacitor can always be formed to have a uniform thickness. It may be based on the steps of spin coating, exposure and development of a resist. Subsequently, a planar conductive plate 153 is provided on the insulating layer 152 by conductive printing, transfer of copper foil, or the like. This does not need to be a branched thin wire, but may be a flat plate. Through the above steps, the capacitor 15 is formed between the thin wire capacitor pattern 151 and the conductive plate 153 on the antenna substrate. At this time, conductive printing is performed so that one end of the conductive plate 153 is connected to the connection terminal 142. For example, conductive printing may be printed on the antenna coil 13 that is electrically connected to the connection terminal 142. Thus, the capacitor 15 forms a parallel circuit for the LSI and the antenna.

The configuration of the capacitor 15 is not limited to the above example, and the insulating layer 152 can be formed by using the sheet base 121 itself. In this case, it is possible to form the capacitor pattern 151 on one side and form the conductive plate 153 on the other side by etching the substrate with copper foil on both sides. Conduction with the antenna coil connection terminal can be performed by through-hole / plating or the like. In this case, the surface on which the capacitor pattern 151 is formed may be basically on either side, but it is convenient to form the capacitor pattern 151 on the same surface as the antenna coil in the sense that it is formed simultaneously with the antenna coil 13.

The specific contents of the capacitor, that is, a capacitor pattern, a dielectric layer (insulating layer), a conductive plate,
Depending on the combination of the steps,
A configuration as shown in Table 1 is conceivable.

[Table 1]

<Lamination of Card Substrate> After the antenna coil 13, the antenna coil connection terminal 14, and the capacitor 15 are formed on the base sheet 121, the core sheet 122 and the oversheets 125 and 126 are laminated on the antenna substrate 121A. An integrated card base is manufactured (FIG. 7A). At this time, the front surface of the core sheet 122 is provided with printing such as a pattern for decorating the card and necessary display and various additional functions in advance, and printing is provided on the back surface side of the core sheet 121 before forming the antenna coil. Is also good. When a magnetic stripe is provided, it is transferred to the front side of the oversheet. Also, the core sheet 121
It is preferable to print registration marks for alignment on all other core sheets and oversheets. It is also preferable that the core sheet 124 be provided with a register mark indicating a position where the concave portion for mounting the IC module is to be cut and a hitting rule (not shown) indicating a punching position of the card. After hot pressing, punching is performed into individual card shapes based on the hit rule. When additional functions such as face photo printing, sign panel, and hologram foil transfer are provided to the card, the functions are performed after the punching.

<Concave Cutting / Capacitor Capacity Adjustment> Thereafter, the concave portion 18 for mounting the IC module is counter-machined.
It is formed by NC processing or the like (FIG. 7B). At this time, when the capacitance between the antenna coil connection terminals 141 and 142 is larger than a predetermined value while monitoring the capacitance of the capacitor between the antenna coil connection terminals 141 and 142, the coupling portion of the capacitor pattern 151 with the antenna coil connection terminal 141 is cut off. Adjust the capacity. In the case of the present invention, the direction of increasing the capacitance of the capacitor cannot be adjusted, so that the capacitance is reduced. However, since the capacitance is actually added to the LSI (IC module), the LSI is optimized. It is desirable that the capacitor is designed to be slightly smaller than the capacitor capacity. Also, the capacitance of the capacitor at this stage measured by the measuring instrument is
Since this is the entire capacity including the internal capacity of the antenna coil and the LSI and after the press forming, there is an advantage that the amount of change does not largely fluctuate by subsequent processing.

<Mounting of Module> After adjusting the capacitance of the capacitor, the third concave portion in the mounting concave portion 18 is filled with the conductive adhesive 19, and the other portion in the first concave portion where the IC module 11 contacts the card base. Then, a normal insulating adhesive 20 is applied, or an insulating adhesive sheet cut into a predetermined shape is temporarily placed on the IC module substrate side or in the first concave portion.

The conductive adhesive may be a thermosetting or hot-melt adhesive in which conductive metal particles or the like are dispersed in a resin, or may be a cream solder, a silver paste, or a metal solder melted by heat. . The IC module 11 is temporarily placed in the mounting recess so that the antenna coil connection terminal 114 of the IC module 11 contacts the third recess filled with these materials, and module sealing is performed.

The module sealing is performed in two steps. This step may be performed first, but for the time being, first, the conductive adhesive filled portion of the third concave portion is heated to perform terminal connection. For this purpose, for example, a heater block 31 having a two-point pinpoint heating section in the portion is used, for example, at 200 ° C. for 10 sec.
Hot pressing is performed under a relatively high temperature condition of kgf / cm ² (FIG. 7D). This melts the cream solder etc.
The antenna coil connection terminals are connected. Subsequently, in order to bond the insulating adhesive, for example, at 150 ° C., 5
The heat press is performed under a comparatively low temperature condition of ² kgf / cm ² for 2 seconds (FIG. 7E). Finally, cooling is performed using a cooling press 33 having an area larger than the substrate size (FIG. 7).
(F)). Thus, the non-contact type IC card of the present invention is completed.

(Examples of Other Materials) <Card Base> Various materials other than vinyl chloride resin and PET can be used for the card base, such as PET-G, polypropylene resin, polycarbonate resin, and acrylic resin. Resins, polystyrene resins, ABS resins, polyamide resins, polyacetal resins, and the like. <Conductive Adhesive> As the conductive adhesive, cream solder and silver paste can be used as described above.
A thermoplastic conductive adhesive sheet, a paste of silver, copper, carbon, or the like, a metal solder, an anisotropic conductive film, or the like can be used. <Insulating adhesive> As the insulating adhesive, a thermoplastic (hot melt) type or a thermosetting / moisture curable adhesive or an adhesive sheet can be used. Further, it may be an adhesive sheet, an adhesive, a cold glue, or the like. The application of the adhesive or the temporary placement of the adhesive sheet may be on the card substrate side or the IC chip side.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a non-contact type IC card according to the present invention will be described below with reference to FIGS. Reference numerals in the embodiments correspond to reference numerals in the drawings referred to. (Example) As shown in FIG. 8, a non-contact type IC card with a built-in capacitor having a six-layer sheet structure was prototyped. Antenna board 1
The thickness of the core sheet 121 to be 21 A is 180 μm.
Using a base material in which a 35 μm thick copper foil is laminated on one side on a white hard vinyl chloride sheet, the antenna coil 13, the antenna coil connection terminals 141 and 142, and the capacitor pattern 151 are formed on the copper foil portion using a photo-etching technique.
Was formed. The antenna coil 13 had a line width of 150 μm and was formed so as to be wound substantially four times around the outer periphery of the card base.

The capacitor pattern 151 is 0.5 mm
At a pitch of 0.2 mm and a line length of 15 mm. On top of this, an epoxy-based photoresist is applied to a uniform thickness, exposed and developed, and a capacitor pattern 1 is formed.
An insulating layer 152 was formed by patterning so as to cover almost the entire surface of the insulating layer 51. The resist film thickness after drying was 30 μm.
A conductive plate 153 was further printed on the resist film with a conductive ink made of silver paste so as to have a thickness of 30 μm. At this time, since the conductive plate and the capacitor pattern 151 are overlapped with a length of 10 mm, the effective area for substantially forming the capacitor is:
0.2 × 10 × 10 = 20 mm ² area. In this capacitor configuration, it is expected that adjustment of 0.5 pF per 1 mm ² is possible, so that adjustment of 10 pF is possible as a whole. The connection of the jumper line 132 was performed in the same manner when forming the insulating layer and printing the conductive plate.

For this antenna substrate 121A, two 180 μm thick white rigid vinyl chloride sheets having a thickness of 180 μm are used as core sheets 122 for thickness adjustment, and two white rigid vinyl chloride sheets 123 and 124 are printed. Two transparent vinyl chloride sheets having a thickness of 50 μm are laminated on the upper and lower sides of the core sheet as the oversheets 125 and 126, and are heat-sealed (150 ° C., 20 kgf /
cm ² for 15 minutes) to produce a card base 12 with an antenna coil embedded therein.

After hot pressing, punching was performed for each card size based on the previously provided hitting rule, and hologram transfer foil transfer, face photograph printing, sign panel transfer, etc. were performed on the card surface.

Next, the IC module mounting portion of the card base 12 having the antenna coil embedded therein is subjected to NC cutting to form the first concave portion 181 to a depth corresponding to the thickness of the external device connection terminal of the IC module and the adhesive sheet. Was cut.
At this stage, the size of the first concave portion is 13 mm × 11.8 mm.
(The radius of curvature of the corner was 2.5 mm), and the depth was 200 μm. Subsequently, the distance between the two antenna coil connection terminals was further cut so as to have a size of approximately 8 mm × 8 mm and a depth of 600 μm, so that the second concave portion 182 was made large and deep enough to embed 115 parts of the mold resin of the IC module. . In addition, a third φ2 mm portion is provided at two places around the antenna coil connection terminals 141 and 142 of the card base around the second concave portion.
The recess (conduction hole) was drilled to a depth of 420 μm with a drill so that the antenna coil connection terminal surface appeared. Further, the entire periphery of the first concave portion was cut with the same size and curvature as the first concave portion and with a width of 0.5 mm to form an outer peripheral groove 184 having a depth of 350 μm (FIG. 3A).

The exposed antenna coil connection terminals 141,
When the capacitance between the capacitors 142 was measured with a measuring instrument (“Impedance gain phase analyzer” manufactured by Hewlett-Packard Company), it was 40 pF. Therefore, in order to set this value to the standard value of 46 pF, four thin lines of the capacitor pattern 151 were cut by an NC cutting process at a portion indicated by an arrow (↑) in FIG. For this, the outer peripheral groove 184 of the portion of the antenna coil connection terminal 141 has a depth of 500.
It was cut to a width of 0.5 mm and a length of 2.0 mm so as to be μm.

On the other hand, an IC chip having both a contact type and a non-contact type functions and a 150 μm thick glass epoxy substrate (size 13 mm × 11.8 mm (curvature radius of corners 2.5 mm)) are provided with a double-sided copper foil. I prepared the one with it. An antenna coil connection terminal 114 is formed on the IC chip side of the substrate, nickel and gold plating is applied to the terminal portion, and a non-contact type IC chip is mounted on the substrate.
Connection with each external device connection terminal was made through the through hole, and wire bonding with the antenna coil connection terminal 114 was performed using a gold wire. Further, the periphery of the IC chip was sealed with epoxy resin.

Third concave portion 18 of the concave portion for mounting the IC module
A cream solder (manufactured by Nihon Handa Co., Ltd.) was potted and molded into each of about 3 cc each. A thermosetting insulating adhesive sheet (manufactured by Toagosei Co., Ltd.) having a thickness of 50 μm on the bottom surface of the first concave portion except for the third concave portion.
Was temporarily placed.

Next, the I prepared as described above is
After the C module 11 was fitted and temporarily placed, module sealing was performed. First, in order to connect the terminals by heating the cream solder filled portion of the third concave portion, a heater block 31 having a two-point pinpoint-shaped heating portion in the portion is used at 200 ° C. for 10 seconds. , 1k
The hot press was performed under the condition of gf / cm ² (FIG. 7).
(D)). Subsequently, in order to perform hot pressing of the adhesive sheet, hot pressing was performed at 150 ° C., 5 sec, and 2 kgf / cm ² using a heater block 32 of a module substrate size (FIG. 7E). Finally, using a cooling press 33 having an area larger than the substrate size, 20 °
The cooling was performed under the conditions of C, 5 sec and 2 kgf / cm ² (FIG. 7 (F)).

As a result, a contactless IC card with a built-in capacitor having a card thickness of 820 μm, excellent surface properties and physical strength, and having an optimally adjusted capacitor capacity was obtained. The resonance frequency of this non-contact IC card is 13.56 MH
z, the communication distance was 10 cm.

[0046]

According to the contactless IC card with a built-in capacitor of the present invention, the capacitance can be easily adjusted to the optimum value in the manufacturing process, so that the optimum resonance frequency can be adjusted regardless of the individual LSI used. It can achieve excellent communication stability. In the method of manufacturing a non-contact type IC card with a built-in capacitor of the present invention, the final adjustment of the capacitor capacity of the card base is performed at the final stage after the card base is hot-pressed. Since the change is small and the optimum resonance frequency can be achieved, the occurrence of defective products is reduced and the yield is improved.
In addition, since the capacitance of the capacitor is adjusted after the steps of providing additional functions such as a face photograph, a sign panel, and a hologram foil transfer, various additional functions can be freely provided without a change in capacitance due to the additional functions.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a non-contact type IC card of the present invention.

FIG. 2 is an antenna board 1 of the non-contact type IC card of FIG. 1;
FIG.

FIG. 3 is an enlarged view of an IC module mounting portion and a capacitor portion.

FIG. 4 is a diagram showing an equivalent circuit of the card.

FIG. 5 is a diagram showing a change in the capacitance of the capacitor when the capacitor pattern is cut.

FIG. 6 is a diagram showing a cross section of an IC module mounting recess.

FIG. 7 is a diagram illustrating a manufacturing process of the non-contact type IC card of the present invention.

FIG. 8 is a diagram illustrating an example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 IC card 11 IC module 12 Card base 13 Antenna coil 14 Antenna coil connection terminal 15 Capacitor 18 IC module mounting concave part 19 Conductive adhesive 20 Insulating adhesive 31 Heater block 32 Heater block 33 Cooling press 112 External device connection terminal 114 IC side antenna coil connection terminal 115 Mold resin 121, 122, 123, 124 Core sheet 121A Antenna substrate 125, 126 Oversheet 141, 142 Antenna coil connection terminal 151 Capacitor pattern 152 Insulating layer 153 Conductive plate 181 First concave portion 182 Second concave portion 183 third concave portion 184 outer peripheral groove

Claims (10)

[Claims] 1. A non-contact type IC having a resonance circuit including an antenna coil and a planar capacitor in a card base, wherein a capacitance of the capacitor in the resonance circuit is adjustable.
In the card, the capacitor has a configuration composed of a group of branched linear patterns, and the capacitor capacity is adjustable by cutting the linear pattern from the branch portion. Contact type IC card. 2. A non-contact type IC having a resonance circuit including an antenna coil and a planar capacitor in a card base, wherein a capacitance of the capacitor in the resonance circuit is adjustable.
In the card, the capacitor has a configuration of a group of linear patterns branched from an antenna coil connection terminal facing the concave portion for mounting the IC module, and the linear pattern is formed when cutting an outer peripheral groove around the concave portion for mounting the IC module. A non-contact type IC card with a built-in capacitor, characterized in that the capacity of the capacitor can be adjusted by cutting off from a branch portion. 3. The linear pattern according to claim 1, wherein each of the linear patterns has a constant unit adjustment amount of capacitance, and the capacitance of the capacitor can be adjusted by the unit adjustment amount.
A non-contact IC card with a built-in capacitor as described in the above. 4. The capacitor according to claim 1, wherein the capacitor comprises a group of a planar conductive pattern and a linear pattern with an insulating layer interposed therebetween, and a conductive pattern formed in a plane. Item 3. Non-contact type I with built-in capacitor according to item 3.
C card. 5. The non-contact IC card with a built-in capacitor according to claim 1, wherein the IC module of the non-contact IC card is a common IC module of a contact type and a non-contact type. 6. The adjustable range of the capacitance of the capacitor is as follows:
2. The method according to claim 1, wherein the pressure is about 0 to +100 pF.
5. A non-contact IC card with a built-in capacitor according to claim 4. 7. The non-contact IC card with a built-in capacitor according to claim 1, wherein the insulating layer comprises a sheet constituting a card base. 8. A method for manufacturing a non-contact type IC card in which a resonance circuit including an antenna coil and a planar capacitor is provided in a card base and a capacitance of the resonance circuit is adjustable. Forming a planar capacitor element composed of a group of linear patterns connected to the terminal and the antenna coil connection terminal on the base material to form an antenna substrate; and covering the planar capacitor element with an insulating layer. Later, a step of covering the flat conductive plate to complete the capacitor, a step of laminating another base material on the antenna substrate to form a card base, and connecting the external device connection terminal of the IC module to the card base. A step of cutting a concave portion to a depth at which the antenna coil can be mounted, and a step of cutting the outer peripheral groove around the concave portion from the antenna coil connection terminal. And adjusting the capacitance by cutting the branch portion of the linear pattern of the capacitors,
Contactless IC with built-in capacitor
Card manufacturing method. 9. The method for manufacturing a non-contact IC card with a built-in capacitor according to claim 8, wherein a group of linear patterns is formed by photo-etching a copper foil layer on a base material. 10. The method for manufacturing a non-contact type IC card with a built-in capacitor according to claim 8, wherein the coating of the flat conductive plate is performed by a screen printing method.