JP7600919B2 - Dual interface card and method of manufacturing same - Google Patents

Description

The present invention relates to a dual interface card capable of contact and non-contact communication with an external device.

Conventionally, IC cards include contact IC cards that input and output electrical signals through an external connection terminal on the surface of the card, and contactless IC cards that input and output electrical signals by electromagnetic induction or the like via an antenna. In addition to these, contact and contactless IC cards, i.e., dual interface cards, are also used, which can realize both the functions of a contact IC card and a contactless IC card with a single IC chip. Among these, dual interface cards can be used as contact IC cards that are effective in preventing external leakage of input and output data during financial settlements, and as highly convenient contactless IC cards that exchange data in close proximity when entering and leaving a room or at a ticket gate at a station. For this reason, dual interface cards are also becoming more and more popular in the market.

Now, dual interface cards are manufactured as follows. First, as described in Patent Document 1, a card substrate containing one or more core sheets is formed, and an area in which an IC module is to be embedded is cut from the surface of the card substrate. Then, the IC module is embedded in the area in which it is to be embedded. Here, a conductor is arranged in one of the one or more core sheets, and the conductor forms a wound antenna section for providing the contactless communication function, and a contact terminal section that is in electrical contact with a terminal of the IC module, and the contact terminal section is arranged, for example, in a meandering shape.

Here, the region to be embedded is cut to include the first recess, the second recess, and the contact opening in the first recess. The first recess is for accommodating the substrate of the IC module, and is cut to a depth that does not expose the contact terminal of the conductor present inside the card substrate. The second recess is for accommodating the sealing portion of the IC module, and is cut to a depth that does not expose the contact terminal of the conductor present inside the card substrate. Meanwhile, the contact opening in the first recess is cut deeper than the first recess until the contact terminal is exposed. By filling the contact opening with a conductive adhesive, the contact terminal and the terminal on the back side of the substrate of the IC module are electrically contacted via the conductive adhesive. Also, by attaching an adhesive tape to the back side of the substrate of the IC module, the IC module is fixed in the first recess of the region to be embedded.

JP 2019-219732 A

To improve the efficiency of manufacturing dual interface cards, it is desirable to use the same adhesive material for both the electrical connection between the IC module and antenna and the mechanical connection between the IC module and card base. However, depending on the material and characteristics of the adhesive layer, the adhesive conditions required to electrically connect the IC module and antenna often differ from the adhesive conditions required to mechanically connect the IC module and card base, and it is believed that the distance conditions between non-adhered bodies in particular have a large effect on the adhesive strength.

This disclosure has been made in light of these circumstances, and aims to provide a dual interface card and a manufacturing method thereof that improves the reliability of both the electrical connection between the IC module and the antenna and the mechanical connection between the IC module and the card base, and that can improve manufacturing efficiency.

The dual interface card according to this embodiment, capable of contact and non-contact communication with an external device, comprises a card base, an antenna having multiple ends disposed inside the card base, and an IC module having an IC chip and multiple terminals electrically connected to the IC chip. The IC module is disposed in a recess provided in the card base so that the multiple terminals and the multiple ends facing each other are electrically connected, and the multiple ends are configured by a repeated folding structure from the outer periphery of the recess toward the center by an antenna wire constituting the antenna, and a part of the multiple ends is exposed in the recess. The recess is configured with a first recess that includes a part of the outer periphery and is separated from each other, a second recess that includes another part of the outer periphery and is separated from each other, and a third recess that is adjacent to all of the first recess and the second recess and is formed closer to the center than these, and at least a part of the multiple ends is exposed in the second recess, the second recess is formed deeper than the first recess, and the third recess is formed deeper than the second recess.

In addition, in a dual interface card according to another embodiment of the present invention, the second recess may continuously expose a repeated folded structure from the outer periphery of the recess toward the center, which is formed by the antenna wires constituting the antennas at the multiple ends.

In a dual interface card according to another embodiment of the present invention, at least the bent portion of the folded structure of the antenna, which is formed by the antenna wires constituting the antennas at the multiple ends and which is repeatedly folded from the outer periphery of the recess toward the center, is overlapped and not exposed in the first recess, and a portion other than the bent portion may be exposed in the second recess.

In addition, in a dual interface card according to another embodiment of the present invention, the IC module may have the multiple terminals and multiple ends that face each other electrically connected to each other via an anisotropic conductive film.

In addition, in a dual interface card according to another embodiment of the present invention, the anisotropic conductive film may be arranged so as to overlap the first recess and the second recess.

In a dual interface card according to another embodiment of the present invention, the outer periphery may be a substantially rectangular shape having sides substantially parallel to the short and long sides of the card base, and the multiple ends may be configured by a repeated folding structure from the outer periphery, which is a side of the recess substantially parallel to the short side of the card base, toward the center by an antenna wire constituting the antenna.

In addition, in a dual interface card according to another embodiment of the present invention, a portion of the antenna other than the bent portion of the folded structure may be inclined with respect to a straight line along the outer periphery.

In addition, in a dual interface card according to another embodiment of the present invention, the recess includes a part of the outer periphery and further includes a fourth recess adjacent to the third recess, the fourth recess is formed deeper than the first recess and shallower than the third recess, and a convex portion of a smaller area than the fourth recess may be formed on the surface of the IC module facing the fourth recess.

According to another embodiment of the present invention, a method for manufacturing a dual interface card capable of contact and non-contact communication with an external device includes an antenna forming step of embedding an antenna wire in a first substrate while applying heat and pressure to form an antenna having multiple ends on one side of the first substrate, a lamination step of laminating a second substrate on the first substrate on which the antenna is formed so as to sandwich the antenna, a punching step of punching the laminate of the first substrate and the second substrate into a card-sized card base, a recess forming step of forming a recess in the card base for embedding an IC module, an IC module preparation step of preparing an IC module having an IC chip and multiple terminals electrically connected to the IC chip, and a card base having the multiple terminals and the multiple ends facing each other. and an IC module bonding process for bonding the IC module to the recess of the card base via a conductive adhesive layer so that the IC module is electrically connected to the recess. The multiple ends are formed by a repeated folding structure from the outer periphery of the recess toward the center by an antenna wire constituting the antenna, and a part of the structure is exposed in the recess. The recess is composed of a first recess that includes a part of the outer periphery and is separated from each other, a second recess that includes another part of the outer periphery and is separated from each other, and a third recess that is adjacent to all of the first recess and the second recess and is formed closer to the center than these. At least a part of the multiple ends is exposed in the second recess, the second recess is formed deeper than the first recess, and the third recess is formed deeper than the second recess.

This embodiment provides a dual interface card and a method for manufacturing the same that improves the reliability of both the electrical connection between the IC module and the antenna and the mechanical connection between the IC module and the card base, and improves manufacturing efficiency.

FIG. 2 is a plan view illustrating the structure of the dual interface card according to the first embodiment. 2 is a cross-sectional view showing a cross section taken along line AA in FIG. 1. 2 is a cross-sectional view showing a cross section taken along line BB in FIG. 1. 1A and 1B are diagrams illustrating an IC module and a connection between the IC module and an antenna. FIG. 1B is a plan view illustrating the structure of a dual interface card according to a second embodiment of the present invention, and corresponds to FIG. 5 is a cross-sectional view taken along line DD in FIG. 5 and corresponds to FIG. 3. FIG. 1B is a plan view illustrating the structure of a dual interface card according to a third embodiment of the present invention, and corresponds to FIG. FIG. 1B is a plan view illustrating the structure of a dual interface card according to a fourth embodiment of the present invention, and corresponds to FIG.

Below, an example of a dual interface card of the present disclosure will be described with reference to the drawings, etc. However, the dual interface card of the present disclosure is not limited to the embodiment and examples described below.

The figures shown below are schematic. Therefore, the size and shape of each part are appropriately exaggerated to make it easier to understand. Hatching showing the cross section of a member is also omitted in each figure. The numerical values such as dimensions of each member and the names of materials described in this specification are examples of embodiments, and are not limited to these, and may be selected and used as appropriate. In this specification, terms that specify shapes or geometric conditions, such as parallel, orthogonal, and perpendicular, are intended to include substantially the same state in addition to their strict meaning.

1. First embodiment An example of a first embodiment of the dual interface card of the present disclosure will be described. Here, for convenience of description, an XYZ coordinate system is set for the dual interface card 1. First, as shown in FIG. 1(a) and FIG. 2(b), the Z axis is taken in the normal direction of the main surface of the dual interface card 1. Then, the direction from the main surface on the side on which the external connection terminals 71 of the IC module 7 are not arranged to the main surface on the side on which the external connection terminals 71 are arranged is defined as the +Z direction or the upward direction in the thickness direction, and the opposite direction is defined as the -Z direction or the downward direction in the thickness direction.

When the dual interface card 1 is viewed from the +Z direction, the straight line perpendicular to both short sides of the dual interface card 1 and the Z axis is defined as the X axis, the direction from one short side closer to the external connection terminal 71 toward the other short side is defined as the +X direction or rightward direction, and the opposite direction is defined as the -X direction or leftward direction. Furthermore, the axis perpendicular to the X and Z axes is defined as the Y axis, the direction from one long side farther from the external connection terminal 71 toward the other long side is defined as the +Y direction or upward, and the opposite direction is defined as the -Y direction or downward.

1(a) is a plan view of the dual interface card 1 seen from the +Z direction, and FIG. 1(b) is a diagram for explaining the arrangement of the antenna 8 by enlarging the vicinity of the external connection terminal 71 of the dual interface card 1 of FIG. 1(a). However, in order to make the configuration of the antenna 8 easier to understand, it is shown in a state in which the IC module 7 is removed. Meanwhile, FIG. 2(a) is a cross-sectional view of the dual interface card 1 of FIG. 1(b) cut along the plane along the line A-A seen from the -Y direction. FIG. 2(a) is a diagram in which the IC module 7 is omitted, and FIG. 2(b) is a diagram in which the IC module 7 is mounted in FIG. 2(a). Also, FIG. 3(a) is a cross-sectional view of the dual interface card 1 of FIG. 1(b) cut along the plane along the line B-B seen from the -X direction, and FIG. 3(a) is a diagram in which the IC module 7 is omitted, and FIG. 3(b) is a diagram in which the IC module 7 is mounted in FIG. 3(a).

As shown in FIG. 1(a), the dual interface card 1 has the form of a generally rectangular thin plate with rounded corners when viewed from the +Z direction. Furthermore, on the surface on the +Z direction side of the dual interface card, an IC module 7 including an external connection terminal 71 can be seen slightly to the upper left of the center, that is, closer to the -X direction and closer to the +Y direction than the center. As shown in FIG. 2(a) and FIG. 2(b), the IC module 7 is embedded in a recess 9 formed in the card base 2, and is arranged so that the surface on the +Z direction side of the external connection terminal 71 is approximately flush with the surface on the +Z direction side of the card base 2. Such a form of the dual interface card 1 complies with ISO/IEC 7816, an international standard for IC cards.

As shown in FIG. 2(a), the card base 2 constituting the card body of the dual interface card 1 is formed by laminating and integrating, in order from the -Z direction side, an oversheet layer 6, a core layer 5, a core layer 4, and an oversheet layer 3. Typically, the oversheet layers 6 and 3 are transparent substrates, and the core layers 5 and 4 are white substrates, but this is not limited thereto. In addition, an antenna wire 83 constituting the antenna 8 is disposed between the core layers 5 and 4 so as to be sandwiched between them.

The antenna wire 83 constituting the antenna 8 is partially exposed in the area of the bottom surface 92p of the second recess 92a, which is formed relatively shallow in the recess 9, and is completely buried inside the card base 2 in the area other than the area. In other words, the antenna wire 83 is buried inside the card base 2, but in the process of cutting the card base 2 to form the recess 9, a part of the antenna wire 83 is cut together with the recess 9 to an extent that it does not break, and the cut surface of the antenna wire 83 is exposed on the bottom surface 92p of the second recess 92a. The recess 9 further includes a first recess 91 formed along the outer periphery 97 side and shallower than the second recess 92a, and a third recess 93 formed closer to the center of the recess 9 than the second recess 92a and deeper than the second recess 92a.

As shown in FIG. 2(b), the IC module 7 is embedded so that the external connection terminal 71 and the substrate 72 supporting it are placed on the bottom surface 92p of the second recess 92a of the recess 9 described above, and the substrate 72 and the bottom surface 92p of the second recess 92a of the card base 2 are mechanically joined via the conductive adhesive layer 11. Incidentally, the third recess 93 houses the IC chip body 74, which is a protruding part of the IC module 7. In addition, the surface of the substrate 72 opposite to the external connection terminal 71 is provided with a terminal 73a electrically connected to the IC chip contained inside the IC module 7. At this time, due to the action of heat and pressure when the IC module 7 is embedded in the recess 9 of the card base 2, the antenna wire 83 exposed on the bottom surface 92p and the terminal 73a are electrically connected via the conductive adhesive layer 11.

Here, both ends of the antenna wire 83 of the antenna 8, which is formed so that most of it is embedded inside the card base 2 and part of it is exposed from the second recesses 92a and 92b, have a shape as shown in the first end 81 and the second end 82 in FIG. 1(b). The first end 81 and the second end 82 are arranged in parallel on the left and right sides along the X-axis, sandwiching the third recess 93 in the center of the recess 9. The first end 81 and the second end 82, which are both ends of the antenna 8, are each configured by a repeated folding structure in which the antenna wire 83 is folded from the outer periphery 97 of the second recesses 92a and 92b toward the center of the recess 9. In other words, the first end 81 and the second end 82 are formed to have a structure called a zigzag shape, a meander shape, or a bellows shape. In this way, by increasing the exposed area of the antenna wire 83 per unit area exposed in the recess 9, the reliability of the electrical connection between the terminal 73a of the IC module 7 and the antenna 8 can be improved.

In addition, the first exposed portion 86 and the second exposed portion 87, which are the regions where the antenna wire 83 is exposed toward the +Z direction side among the regions where the first end 81 and the second end 82 are arranged, are formed within the range of the second recesses 92a and 92b of the recess 9, respectively. In addition, the first recess 91 is formed in the portion of the recess 9 excluding the third recess 93 and the second recesses 92a and 92b, separated on the +Y direction side and the -Y direction side. Here, the second recesses 92a and 92b have approximately the same depth, and are both formed deeper than the first recess 91. In order to facilitate understanding, in FIG. 1(b), the region of the first recess 91 is displayed with a horizontal line pattern, and the regions of the second recesses 92a and 92b are displayed with a dot pattern. The same applies to FIG. 5, FIG. 7(a), and FIG. 8(a) described later.

As shown in Figures 3(a) and 3(b), the recesses 9 of the card base 2 have two different depths, a first recess 91 and second recesses 92a, 92b, at the location where the substrate 72 of the IC module 7 is embedded. Therefore, the distance of the gap between the substrate 72 and the card base 2 varies depending on the location, and as a result, the thickness of the conductive adhesive layer 11 sandwiched between them after bonding varies. In other words, the depth of the recesses 9 of the card base 2 facing the region of the substrate 72 where the terminal 73a is formed is different from the region separated from the terminal 73a in the X direction, and the second recess 92a faces the former region, and the first recess 91, which is shallower than the second recess 92a, faces the latter region.

Here, since the terminal 73a is a layer formed of copper foil or the like of a predetermined thickness, it extends a predetermined thickness further in the same direction from the surface on the -Z direction side of the substrate 72. Therefore, when the IC module 7 is pressed against the card base 2 by applying heat and pressure, the depth of the second recess 92a is determined so that the distance between the terminal 73a via the conductive adhesive layer 11 and the antenna wire 83 exposed on the bottom surface 92p of the second recess 92a is within an appropriate range. In other words, at that distance, good conduction between the terminal 73a and the antenna wire 83 can be obtained.

However, in the region of the substrate 72 that is spaced apart from the terminal 73a along the Y-axis direction, even if the gap between the substrate 72 and the card base 2 is the distance described above, it is not necessarily possible to achieve a good mechanical connection between the IC module 7 and the card base 2. In other words, the gap conditions for a good electrical connection between the terminal 73a and the antenna wire 83 are generally different from the gap conditions for a good mechanical connection between the IC module 7 and the card base 2.

In contrast, in this embodiment, in the region of the substrate 72 spaced apart from the terminal 73a along the Y-axis direction, the gap between the substrate 72 and the card base 2 improves the adhesive strength of the IC module 7 and the card base 2, and the depth of the recess 9 of the card base 2 is changed to improve the mechanical connection between them. Specifically, the recess 9 in this region is the first recess 91, which is shallower than the second recess 92a. This is because the depth of the second recess 92a is determined in consideration of the electrical connection between the terminal 73a extending out from the substrate 72 in the -Z direction and the antenna wire 83. Therefore, if the depth of the recess 9 of the card base 2 is made the same as the second recess 92a in the region where the terminal 73a does not exist, the gap between the substrate 72 and the card base 2 will be too long, and the conductive adhesive layer 11 will not be sufficiently compressed, and appropriate adhesive strength will not be obtained.

Therefore, the dual interface card 1 of this embodiment can improve the reliability of both the electrical connection between the IC module 7 and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2. Specifically, for the same conductive adhesive layer 11, the depth of the second recesses 92a and 92b that improve the electrical connection between the IC module 7 and the antenna 8 is different from the depth of the first recess 91 that improves the mechanical connection between the IC module 7 and the card base 2. That is, the second recesses 92a and 92b are formed deeper than the first recess 91. Also, by configuring the first recess 91 and the second recesses 92a and 92b in this way, the electrical connection between the IC module 7 and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2 can be realized by the same conductive adhesive layer 11. This improves the efficiency of manufacturing the dual interface card 1.

The configuration of the dual interface card 1 of this embodiment and its manufacturing method are described in detail below.

(a) Card Base The card base 2 refers to the card body excluding the IC module 7 constituting the dual interface card 1. As described above, the card base 2 typically has a configuration in which an oversheet layer 6, a core layer 5, a core layer 4, and an oversheet layer 3 are laminated in this order from one end on the −Z direction side in the thickness direction. In addition, an antenna 8 wound in a loop shape and formed of a coated conductor wire or the like is disposed between the core layer 5 and the core layer 4. The card base 2 may refer to both the card before the recess 9 is formed and the card after the recess 9 is formed, and may refer to both the card not including the antenna 8 and the card including the antenna 8. In addition, the first end 81 and the second end 82, which are either the start point or the end point of the antenna 8, are formed by processing the antenna wire 83 into a predetermined shape as described above.

However, the layer structure of the card base 2 is not limited to this, and may be a three-layer structure of an oversheet layer, a core layer, and an oversheet layer, a two-layer structure of a core layer and a core layer, or a five-layer structure of an oversheet layer, a core layer, a core layer with an antenna formed thereon, a core layer, and an oversheet layer. In addition, printing or an embedded magnetic stripe may be applied to the surface of the oversheet layer 3 or 6 of the card base 2 opposite the core layer 4 or 5, and printing may be applied to the surface of the core layer 4 or 5 adjacent to the oversheet layer 3 or 6.

The thickness of the card base 2 is preferably 0.76 mm or more and 0.84 mm or less in terms of compliance with standards such as ISO/IEC 7816, but may be outside this range.

(i) Core layer As the core layers 4 and 5, various types of white or colored plastic sheets can be widely used, and the following single films or composite films can be used. For example, polyethylene terephthalate (PET), PET-G (terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer), polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polycarbonate, polyamide, polyimide, cellulose diacetate, cellulose triacetate, polystyrene, ABS, polyacrylic acid ester, polypropylene, polyethylene, polyurethane, etc. The thickness of the core sheet can be appropriately selected taking into account the overall thickness of the card, and can be, for example, about 0.25 mm or more and 0.38 mm or less. As described later, it is necessary to arrange the antenna 8 on the surface of either the core layer 4 or 5 so that it is sandwiched between the two core layers.

(ii) Over-sheet layer The over-sheet layers 3 and 6 are usually made of the same material as the core layer, and are often made of a transparent material having a thickness of about 0.05 mm or more and 0.10 mm or less. From the viewpoint of preventing curling when the laminate of the core layer and the over-sheet layer is integrated by heat pressing or the like, it is preferable that the over-sheet layers 3 and 6 have the same thickness, but they do not necessarily have to be the same.

The material of the oversheet layer may be any material that is adhesive when heated, but even if the oversheet layer itself is not adhesive when heated, the core layer and the oversheet layer can be integrated by additionally forming a layer of a known adhesive that generates adhesive force when heated or the like between the core layer and the oversheet layer. In addition, when the dual interface card 1 is used as a magnetic card, a magnetic tape may be embedded in advance by thermal transfer or the like into the main surface side opposite the core layers 4 and 5 of either or both of the oversheet layers 3 and 6.

(iii) Antenna Sheet In this embodiment, as described later, an antenna 8 is formed on one surface of the core layer 5, and a first end 81 and a second end 82, which are ends of an antenna wire 83 constituting the antenna 8, are processed into a predetermined shape and arranged. The formation of the antenna 8 on the core layer 5 is performed by applying a predetermined heat pressure to the antenna wire 83, and embedding the antenna wire 83 in the core layer 5 while melting the core layer 5 and the coating of the antenna wire 83. An intermediate product in which the antenna 8 is embedded in the core layer 5 may be referred to as an antenna sheet 12. The antenna sheet 12 can be distributed on the market by itself as a part for manufacturing the dual interface card 1, or a commercial form may exist in which a sheet material such as the core layer 5 is supplied to a processor, who processes it into an antenna sheet 12 and delivers it to a supplier.

The method of forming the antenna sheet 12 will be described in detail later, but the outline is as follows. First, a coated conductor covered with an insulating material is embedded on the surface of the core layer 5 using a winding forming machine, starting from either the first end 81 or the second end 82 and ending at the other. That is, while applying a predetermined heat pressure to the core layer 5, an antenna supply head is drawn into a loop shape as shown in FIG. 1(a), and the antenna wire 83 supplied from the antenna supply head is sequentially embedded in the core layer 5.

The first end 81 and second end 82, which are either the start or end of the antenna wire 83, are aligned to the left and right of the intended mounting position of the IC module 7, with portions of them overlapping the terminals 73a and 73b of the IC module 7, to form a predetermined shape as described below. The winding machine then cuts the antenna wire 83 after forming either the first end 81 or the second end 82, which are the end points of the antenna 8. In this way, the antenna sheet 12 is completed.

(iv) Antenna The antenna 8 formed in the core layer 5 has a first end 81 and a second end 82 electrically connected to the terminals 73a and 73b of the IC module 7, so that the IC chip of the IC module 7 and the antenna 8 form a communication circuit for non-contact communication. The communication circuit may be one that performs close-proximity communication using, for example, the HF frequency band of 13.56 MHz specified in ISO/IEC 18092, ISO/IEC 144443, etc. Alternatively, it may be one that performs communication using, for example, the UHF frequency band of 920 MHz, the LF frequency band of 125 KHz, or the microwave frequency band of 2.45 GHz.

When the dual interface card 1 is held over an external device such as a reader/writer, a magnetic field generated by the reader/writer generates a current in the communication circuit, which supplies power to the IC chip. This enables the IC chip to be driven, enabling contactless transmission and reception of information with the reader/writer, and reading and rewriting information from and to the memory.

The antenna wire 83 constituting the antenna 8 is typically formed of a coated conductor wire in which the periphery of a copper wire is coated with an insulating material. In addition to this, it is also possible to select copper alloy wire such as Cu-Ni, Cu-Cr, Cu-Zn, Cu-Sn, Cu-Be, or various metal wires and metal alloy wires such as iron, stainless steel, and aluminum. By using coated conductor wire, the dual interface card 1 can be manufactured more inexpensively than, for example, a copper foil etching method.

There are no particular limitations on the diameter of the antenna wire 83, so long as the characteristics as a non-contact communication circuit can be ensured, but it can be, for example, 0.03 mm or more and 0.30 mm or less, and preferably 0.05 mm or more and 0.15 mm or less. By keeping it in the latter range, durability against heat pressure due to embedding processing and external forces due to cutting processing can be improved, and good communication characteristics can be ensured.

Next, the configuration of the first end 81 and the second end 82 will be described in detail. In FIG. 1(b), one end of the antenna wire 83 extending from the -X direction toward the +X direction then forms the first end 81, which is a structure that is repeatedly folded back from the outer periphery 97 toward the center, near the -X direction side of the third recess 93 of the recess 9. Similarly, one end of the antenna wire 83 extending from the +X direction toward the -X direction then forms the second end 82, which is a structure that is repeatedly folded back from the outer periphery 97 toward the center, near the +X direction side of the recess 9. The antenna wire 83 extends so that the folded back structure is repeated multiple times.

The folded structure has a substantially arc-shaped bend at the +Y and -Y ends, i.e., at the upper and lower ends, and the portion other than the bend connecting the upper end bend and the lower end bend is substantially straight or curved. However, from the viewpoint of efficiency in embedding the antenna wire 83 in the core layer 5 and saving material for the antenna wire 83, it is preferable to form the portion other than the bend as substantially straight as possible.

In this embodiment, the outer periphery 97 is a substantially rectangular shape with sides that are substantially parallel to the short and long sides of the card base 2. The first end 81 and the second end 82 are formed by a repeated folding structure that is formed by the antenna wire 83 that constitutes the antenna 8, from sides 97a and 97b of the outer periphery 97, which are sides of the recess 9 that are substantially parallel to the short sides of the card base 2, toward the center.

The portion of the first end 81 other than the bent portion of the folded structure extends along a straight line parallel to the Y axis along the side 97a of the outer periphery 97 of the recess 9, and the center-to-center distance, i.e., the pitch, of the zigzag-shaped antenna wire 83 between adjacent portions other than the bent portion is substantially constant. Furthermore, the width of the entire first end 81 and the first exposed portion 86 in the direction along the Y axis is W12, and the width of the exposed portion of the antenna wire 83 in the direction along the X axis is substantially the same as the width of the second recess 92a, so that the antenna wire 83 is arranged along the contour of a rectangle. The distance from the end on the +Y side to the end on the -Y side of the folded structure, i.e., the length from the upper end to the lower end, is substantially the same length.

In addition, in this embodiment, the first exposed portion 86 of the first end 81, which is the region where the antenna wire 83 is actually exposed from the card base 2, includes a continuous section of the antenna wire 83 from the end on the -X side of the second recess 92a to the end on the +X side. That is, the entire antenna wire 83, including the bent portion of the folded structure and the portion other than the bent portion, is exposed in the second recess 92a, and the conductor is exposed without being covered by the card base 2 or a covering material. At this time, the width W11 of the second recess 92a in the direction along the Y axis is longer than the width W12 of the first end 81 in the direction along the Y axis. Note that the above description of the first end also applies to the second end 82 by replacing the side 97a of the recess 9 with 97b, the second recess 92a with 92b, and the first exposed portion 86 with the second exposed portion 87, respectively.

The pitch of the antenna wire 83 described above depends on the capacity of the winding machine and the quality of the antenna sheet 12 after the antenna wire 83 is embedded in the core layer 5, but is preferably 0.50 mm or less, and more preferably 0.25 mm or less. By setting the pitch in the former range, the exposed area of the antenna wire 83 per unit area at the first end 81 can be improved, and the area of electrical connection with the terminal 73a of the IC module 7 can be expanded. This improves the reliability of the electrical connection and reduces the electrical resistance of the contact portion between the antenna wire 83 and the terminal 73a. Furthermore, by setting the pitch in the latter range, the above-mentioned effect can be further increased.

In this embodiment, the +X end of the region of the first end 81 along the X axis is approximately the same as the boundary between the second recess 92a and the third recess 93, and the -X end is located on the -X side of the end of the second recess 92a, which is the outer periphery 97 of the recess 9. In this way, if the +X end of the first end 81 is approximately the same as the boundary between the second recess 92a and the third recess 93, or is located on the -X side of the boundary, the antenna wire 83 is not cut when cutting the third recess 93, or the amount of cutting of the antenna wire 83 can be reduced. This makes it possible to suppress branching of the antenna wire 83, which is more likely to occur the deeper the cutting depth is, i.e., the occurrence of whiskers.

In addition, the end of the first end 81 along the X direction is located on the -X side of the end of the second recess 92a, which is the outer periphery 97 of the recess 9. This allows the antenna wire 83 to be densely packed in an uninterrupted area even if the antenna 8 is misaligned with respect to the core layer 5 or the recess 9 is misaligned. This ensures a reliable electrical connection with the terminal 73a of the IC module 7. However, the end of the first end 81 along the X direction may be located on the +X side of the boundary between the second recess 92a and the third recess 93, or the end of the -X side may be located on the +X side of the end of the second recess 92a, which is the outer periphery 97 of the recess 9.

The above description concerns the relationship between the first end 81 of the antenna 8 and the terminal 73a of the IC module 7 that electrically connects thereto, but a similar relationship also holds between the second end 82 and the terminal 73b that electrically connects thereto. Also, in this embodiment, it has been described on the premise that there are two ends of the antenna 8 for electrically connecting with the IC module 7, the first end 81 and the second end 82, but the antenna 8 may have three or more ends, and the IC module 7 may have the same number of corresponding terminals.

(b) IC Module Next, each part of the main components of the IC module 7 will be described mainly with reference to Fig. 2(b) and Fig. 4. Fig. 4(a) is a view of the external connection terminal 71 of the IC module 7 seen from the +Z direction side, similar to Fig. 1(a). Fig. 4(b) is a view of the IC module 7 seen from the -Z direction side, opposite to Fig. 4(a). Most of the molded part 74b of the IC chip body 74 is omitted here so that the inside can be seen through. Fig. 4(c) is an enlarged cross-sectional view of part C near the terminal 73a in Fig. 2(b).

The IC module 7 is embedded in a recess 9 formed in the card base 2, and the terminals 73a and 73b of the IC module 7 are electrically connected to the first end 81 and the second end 82 of the antenna 8, respectively, to form a communication circuit for contactless communication. In addition, contact communication can be performed with a contact type reader/writer or the like through the external connection terminal 71 provided on the IC module 7.

The substrate 72 is made by attaching copper foil to the front and back of a flexible resin film such as glass epoxy resin or polyimide resin with an adhesive, and leaving the copper foil attached to the front and back of the resin film to form a specified pattern. Specifically, a photosensitive material is applied, a film plate with a specified pattern is placed, exposed, and the non-photosensitive portion is etched away in order to form an external connection terminal 71 on one copper foil surface of the resin film and terminals 73a and 73b on the other copper foil surface. This forms the substrate 72 with some of the copper foil remaining in a specified pattern on the front and back of the resin film. In addition, the substrate 72 is provided with a plurality of bonding holes 76, which are through holes for wire bonding to the external connection terminals 71.

There is no particular limit to the thickness of the substrate 72, but taking into consideration the ability to follow the bending of the card base 2 to some extent, the thickness can be, for example, 0.03 mm or more and 0.50 mm or less, and preferably 0.07 mm or more and 0.20 mm or less.

As shown in FIG. 4(a), the external connection terminal 71 has each section of the external terminal defined by the ISO/IEC 7816-2 standard. As shown in FIG. 4(b), each of these sections and the IC chip 74a are connected by wires 75 such as gold wires through the above-mentioned bonding holes 76 provided in the substrate 72. Similarly, the terminals 73a and 73b are connected to the IC chip 74a by wires 75. These bonding holes 76 and wires 75 are covered and protected by the molded portion 74b.

An IC chip body 74 is disposed on the surface of the substrate 72 opposite to the surface on which the external connection terminals 71 are formed. The IC chip body 74 is composed of an IC chip 74a bonded and fixed to the substrate 72 with an adhesive, bonding wires 75 for connection, and a molded part 74b which is a sealing resin for protecting these. The IC chip 74a includes a CPU for controlling the operation of both contact communication and contactless communication, a storage device such as RAM, ROM, EEPROM, flash memory, and various circuits such as an interface circuit that decodes input signals and generates output signals for contact communication and contactless communication, and a power generation circuit. Note that the various circuits may be provided as elements separate from the IC chip 74a.

The molded portion 74b is provided as a protruding portion that covers the IC chip 74a and the wires 75 to protect them from external force loads and environmental loads. UV-curable resin, thermosetting resin, or the like is used for the molded portion 74b.

The thickness of the IC chip body 74 depends on the thickness of the IC chip 74a inside and the shape of the bonded wires, but can be, for example, 0.45 mm or more and 0.75 mm or less. The total thickness of the IC module 7 can be, for example, 0.35 mm or more and 1.0 mm or less, and preferably 0.40 mm or more and 0.65 mm or less. By being in the latter range, the depth of the third recess 93 can be made 0.7 mm or less, and the total thickness of the dual interface card 1 can be kept to 0.84 mm or less as defined by the ISO/IEC 7816 standard.

(c) Conductive Adhesive Layer After forming the recess 9 for embedding the IC module 7 in the card base 2 by cutting processing using an end mill or the like, the conductive adhesive layer 11 is described below, which embeds and fixes the IC module 7 in the recess 9 and electrically and mechanically connects it. As shown in Fig. 4(c) , the conductive adhesive layer 11 is a liquid or tape-like member that is disposed so as to be sandwiched between the core layer 5 in the portion where the antenna wire 83 is cut and exposed on the bottom surface 92p, the substrate 72 of the IC module 7 that is embedded and disposed above it, and the terminal 73a formed on the substrate 72.

The conductive adhesive layer 11 may be applied or affixed in advance to the surface of the substrate 72 of the IC module 7 opposite the external connection terminal 71, or may be applied or affixed to the bottom surface 92p of the recess 9 of the card base 2 after cutting.

A typical conductive adhesive layer 11 may be applied or affixed to the entire back surface of the substrate 72 or to the recess 9 at locations corresponding to the first recess 91 and the second recesses 92a, 92b that are disposed along the outer periphery 97 of the recess 9, in order to mechanically connect the IC module 7 and the cut card base 2. In this way, the electrical connection between the IC chip 74a and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2 can be achieved with the same type of conductive adhesive layer 11, which contributes to simplifying the process.

However, the conductive adhesive layer 11 may be applied or affixed to the rear surface of the substrate 72 so as to cover only the areas of the terminals 73a and 73b, and a different adhesive that does not have electrical conductivity may be applied or affixed to the rest of the rear surface of the substrate 72. This is because it is not necessary to consider the electrical conductivity of the different adhesive, making it easier to select an adhesive that is more advantageous for mechanical connection.

ACF (Anisotropic Conductive Film), i.e., anisotropic conductive film, or ACP (Anisotropic Conductive Paste) can be used as the conductive adhesive layer 11 that can be used for both electrical and mechanical connection. In addition, so-called conductive paste, in which silver particles are dispersed as a filler in epoxy resin, can also be used. Among them, if ACF is used, the ACF can be thermally laminated over the entire back surface of the substrate 72 of the IC module 7, and the IC module 7 can be embedded in the recess 9 of the cut card base 2, and then heat pressed at a predetermined temperature and load to easily achieve electrical connection between the IC chip 74a and the antenna 8. Furthermore, since the mechanical connection of the IC module 7 to the card base 2 can be achieved at the same time, the mounting process of the IC module 7 to the card base 2 can be simplified.

The electrical connection between the IC chip 74a and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2 when ACF is used as the conductive adhesive layer 11 can be explained as follows based on FIG. 4(c). The conductive adhesive layer 11 has a structure in which conductive particles 11a, each of which is a spherical resin or a spherical metal and has a metal film formed around it, are dispersed in adhesive 11b, which is a binder containing an adhesive component. Here, heat pressure is applied to the substrate 72 from the +Z direction to the -Z direction so that the conductive adhesive layer 11, which is arranged so as to be sandwiched between the core layer 5, where a part of the antenna wire 83 is exposed, the substrate 72 of the IC module 7, and the terminal 73a formed on the substrate 72, is compressed.

As a result, strong heat pressure is applied to the conductive adhesive layer 11 at a particularly narrow area between the core layer 5 and the terminal 73a, and the conductive particles 11a of the conductive adhesive layer 11 at this area are pressed against the exposed antenna wire 83 and terminal 73a of the core layer 5 along the thickness direction of the conductive adhesive layer 11. Also, when the conductive particles 11a are small, the conductive particles 11a overlap in a daisy chain from the antenna wire 83 to the terminal 73a along the thickness direction of the conductive adhesive layer 11. That is, the exposed antenna wire 83 and the terminal 73a are electrically connected through the conductive particles 11a. On the other hand, between the core layer 5 and the substrate 72 in the area where the terminal 73a does not exist, the conductive particles 11a are not compressed to the extent that they are pressed against the antenna wire 83 and the terminal 73a along the thickness direction of the conductive adhesive layer 11, or to the extent that they overlap in a daisy chain. However, the adhesive force of the adhesive 11b generated by the heat pressure mechanically connects the core layer 5 and the substrate 72.

As described above, the IC module 7 has the opposing terminals 73a and 73b and the first end 81 and second end 82 electrically connected to each other, for example, via an ACF. The ACF is disposed in a region along the outer periphery 97 of the recess 9 so as to overlap the first recess 91 and the second recesses 92a, 92b in a plan view along the Z-axis direction.

(d) Recess The recess 9 formed in the card base 2 for embedding the IC module 7 includes a part of the outer periphery 97 and has a first recess 91 separated from each other. The recess 9 also includes another part of the outer periphery 97 and has second recesses 92a and 92b separated from each other, and a third recess 93 adjacent to the first recess 91 and the second recesses 92a and 92b and formed closer to the center than these. In this embodiment, as shown in FIG. 1B, the second recesses 92a and 92b are approximately rectangular areas in a plan view along the Z axis, respectively arranged on both sides along the X axis sandwiching the central third recess 93. As described above, the first end 81 and the second end 82 of the antenna 8 overlap the second recesses 92a and 92b, respectively, and the first exposed portion 86 and the second exposed portion 87, which are exposed portions of the antenna wire 83, are respectively configured as the overlapping areas.

On the other hand, the first recess 91 is adjacent to each of the second recesses 92a and 92b, and is a region that is divided and arranged on both sides along the Y axis sandwiching the central third recess 93. In this embodiment, the first recess 91, the first end 81, and the second end 82 do not overlap each other in a plan view along the Z axis. The second recesses 92a and 92b have approximately the same depth, but are formed deeper than the first recess 91, and the third recess 93 is formed deeper than the second recesses 92a and 92b.

As shown in Figures 3(a) and 3(b), the depth d1 of the first recess 91 and the depth d2 of the second recesses 92a, 92b can be set independently as optimal depths for different purposes. That is, the depth d1 of the first recess 91 can be determined in consideration of providing a good mechanical connection between the IC module 7 and the card base 2. The depth d2 of the second recesses 92a, 92b can be determined independently of the depth d1 of the first recess 91 in consideration of providing a good electrical connection between the terminals 73a, 73b of the IC module 7 and the exposed antenna wire 83.

First, the depth d1 of the first recess 91 can be considered as follows. For example, the thickness of the substrate 72 is Tp1, the thickness of the conductive adhesive layer 11 is Tacf1, the amount of shrinkage of the conductive adhesive layer 11 in the thickness direction when a predetermined heat pressure is applied is Δacf1, and the amount of shrinkage of the card base 2 in the thickness direction is Δcb1. In this case, if the surface of the external connection terminal 71 of the IC module 7 is made to be approximately the same as the surface of the card base 2, the depth d1 of the first recess 91 is d1 = Tp1 + Tacf1 - Δacf1 - Δcb1. Here, the optimal d1 can be determined by determining the heat pressure conditions, which are the conditions of load, temperature, time, etc., under which the adhesive strength of the IC module 7 and the card base 2 is maximized, and Δacf1 and Δcb1 at that time.

Next, the depth d2 of the second recesses 92a, 92b can be considered as follows. For example, the thickness of the terminal 73a extending from the substrate 72 in the -Z direction is defined as Tp2, and the above definitions are used for the other dimensions. In this case, the depth d2 of the second recess 92a is d2 = Tp1 + Tp2 + Tacf1 - Δacf1 - Δcb1. Here, the optimal d2 can be determined by determining the heat and pressure conditions that provide the best electrical connection between the terminal 73a of the IC module 7 and the exposed antenna wire 83, and the Δacf1 and Δcb1 at that time.

Now consider using the same conductive adhesive layer 11 for both the mechanical connection between the IC module 7 and the card base 2, and the electrical connection between the terminal 73a of the IC module 7 and the antenna wire 83. In this case, the heat and pressure conditions applied to the IC module 7 described above are the same for the first recess 91 and the second recesses 92a, 92b. Note that when the conductive adhesive layer 11 is ACF and the average particle size of the conductive particles is dc1, generally Tacf1>dc1, and in order to achieve proper electrical connection, it is preferable that Tacf1-Δacf1=dc1 or Tacf1-Δacf1<dc1.

At this time, the conductive particles contained in the ACF that fills the gap between the terminal 73a and the antenna wire 83 come into contact with both the terminal 73a and the antenna wire 83 either as is or compressed, ensuring a reliable electrical connection. However, if the value of Tacf1-Δacf1 is made extremely small, the conductive particles in the ACF may be destroyed and good electrical connection may not be achieved. To prevent such destruction of the conductive particles, for example, it is preferable that Tacf1-Δacf1>dc1/2.

On the other hand, when the conductive adhesive layer 11 is ACF, the appropriate value of Δacf1 for improving the mechanical connection between the IC module 7 and the card base 2 is considered to be the same as or in a range close to the conditions for achieving the appropriate electrical connection described above. This is because when the ACF is in a state where it can achieve optimal electrical connection, the adhesive force that mechanically fixes and maintains the terminal 73a and the antenna wire 83 in that state is also considered to be strong. If the conditions for improving the mechanical connection and the conditions for improving the electrical connection are the same, the depth d2 of the second recess 92a needs to be deeper than the depth d1 of the first recess 91 by an amount that approximates the thickness Tp2 of the terminal 73a.

For example, the depth of the first recess 91 is, for example, about 0.1 mm or more and 0.4 mm or less, and the depth of the second recesses 92a and 92b is, for example, about 0.12 mm or more and 0.5 mm or less. When the thickness of the terminals 73a and 73b is 0.015 mm or more and 0.15 mm or less, it is preferable that the difference between the depth of the second recesses 92a and 92b and the depth of the first recess 91 is about 0.005 mm or more and 0.2 mm or less. It is even more preferable that the difference is 40% or more and 120% or less of the thickness Tp2 of the terminals 73a and 73b. In particular, in the latter case, when the conductive adhesive layer 11 is an ACF, the thickness of the conductive adhesive layer 11 can be adjusted by heat and pressure so that the optimal conditions for the electrical connection of the IC module 7 and the antenna 8 and the mechanical connection of the IC module 7 and the card base 2 overlap.

In this way, the cross section after mounting the IC module 7 in the recess 9 of the card base 2 is as shown in Figures 3(a) and (b). That is, the thickness of the conductive adhesive layer 11 in the first recess 91 is d11, and the thickness of the conductive adhesive layer 11 in the second recess 92a is d22 in the area other than the terminal 73a, and d3 in the area of the terminal 73a. When the above-mentioned conditions for improving the mechanical connection and the conditions for improving the electrical connection are the same, d11 = d3.

The specific cutting order for forming such recesses 9 in the card base 2 can be determined arbitrarily depending on the milling program for the cutting process. An exemplary processing order determined from the viewpoint of efficient processing time and ensuring cutting quality is, for example, in FIG. 1(b), first, the area common to the first recess 91 and the second recesses 92a, 92b along the outer periphery 97 is cut at the depth of the first recess 91 while moving the milling tool counterclockwise or clockwise. Next, these central areas are cut at the depth of the third recess 93, which is deeper than the first recess 91, while moving the milling tool counterclockwise or clockwise in the same manner.

Finally, the area common to the second recesses 92a, 92b is cut at a depth deeper than the first recess 91 and shallower than the third recess 93 while moving the milling tool. The second recesses 92a, 92b may be cut by first cutting only the second recess 92a while moving the milling tool counterclockwise or clockwise, and then cutting only the second recess 92b in the same manner. Alternatively, the milling tool may be moved left and right across the second recesses 92a, 92b, and cut continuously while shifting it from top to bottom in sequence, to form the second recesses 92a, 92b simultaneously.

(e) Method for Manufacturing the Dual Interface Card Next, an example of a method for manufacturing the dual interface card 1 using the above-described card base 2, IC module 7, and conductive adhesive layer 11 will be described.

First, a coated conductor wire coated with an insulating material is embedded as an antenna wire 83 on the surface of either the core layer 5 or 4 on the side not adjacent to the oversheet layer 6 or 3, using a winding forming machine, starting from either the first end 81 or the second end 82 and ending at the other. Specifically, for example, while applying a predetermined heat pressure to the core layer 5, an antenna supply head is drawn into a loop shape as shown in FIG. 1(a), and the antenna wire 83 supplied from the antenna supply head is sequentially embedded in the core layer 5.

Here, the antenna wire 83 is arranged at a predetermined position on the left and right of the intended mounting position of the IC module 7 so that the first end 81 and the second end 82 are aligned in the left-right direction, and the antenna wire 83 is cut at its end point. The movement of the winding machine is changed to adjust the arrangement position of the antenna wire 83 so that the first end 81 and the second end 82 are formed by a repeated folding structure of the antenna wire 83 constituting the antenna 8 from the outer periphery 97 to the center of the recess 9. In addition, the antenna 8 is embedded and formed in the core layer 5 so that the part of the antenna wire 83 other than the bent part of the folding structure is aligned along a straight line along the Y-axis, which is a straight line along the outer periphery 97, and the first end 81 and the second end 82 are each aligned along a rectangular outline.

Next, using the core layer 5, which is the antenna sheet 12 on which the antenna 8 is formed, the oversheet layer 6, core layer 5, core layer 4, and oversheet layer 3 are stacked in this order from the bottom in the thickness direction, as shown in Figure 2 (a). After that, the laminate of the large sheets on which the cards are arranged in a multi-faceted manner vertically and horizontally is sandwiched between stainless steel plates from above and below in the thickness direction, and heat and pressure are applied to the laminate via the stainless steel plates.

By going through this type of heat pressing process, a card base consisting of large sheets in which the layers of the laminate are integrated can be obtained. Also, if either the oversheet layer or the core layer has heat resistance such that they do not heat fuse at a specified temperature, an adhesive sheet that heat fuses at a specified temperature can be sandwiched between the layers, or an adhesive can be applied, and then these can be subjected to a heat pressing process to obtain a card base consisting of large sheets in which the layers are integrated.

The large-sized card base obtained as described above, on which the cards are arranged in a multi-faceted vertical and horizontal arrangement, is punched out by a punching machine into the card base 2 that is the size of an ISO/IEC 7816 card. In addition, a recess 9 for embedding the IC module 7 is formed in the card base 2 by cutting using an end mill. This results in the cut card base 2. As described above, the recess 9 is made up of a total of three stages: the first recess 91 and second recesses 92a, 92b for housing the flat substrate 72 of the IC module 7, and the third recess 93 for housing the convex IC chip body 74.

The depth of the first recess 91 is determined taking into consideration that the IC module 7 is embedded and bonded to the card base 2, and that the surface of the external connection terminal 71 is approximately flush with the surface of the non-cut area of the card base 2. The depth of the second recesses 92a and 92b corresponds to the embedding depth of the first end 81 and second end 82 of the antenna 8. In other words, when the second recesses 92a and 92b are formed by cutting, a part of the antenna wire 83 of the first end 81 and second end 82 is exposed on the bottom surface 92p.

In other words, the depth from the surface of the card base 2 on which the external connection terminal 71 is exposed to the bottom surface 92p of the second recesses 92a, 92b is d2. The distance from this surface to the upper end of one of the antenna wires 83 at the first end 81 or the second end 82 is d201, and the distance from this surface to the lower end of that one of the antenna wires 83 is d202. In this case, the relationship d201<d2<d202 holds for each of the values of d2, d201, and d202. If this is not satisfied, the antenna wire 83 will be broken by the cutting process, or will not be exposed from the bottom surface 92p.

Meanwhile, separate from the manufacturing of the card base 2 and the cutting process for forming the recesses 9, the conductive adhesive layer 11 is attached to the IC module 7. The IC module 7 is usually a module tape in which the IC module 7 is continuously formed on a long tape in one or two rows. A tape-shaped ACF is attached to the surface of the substrate 72 opposite the surface of the module tape on which the external connection terminals 71 are formed, while applying a certain amount of heat and pressure. The module tape with the ACF attached is then punched out by a punching machine into an approximately rectangular IC module 7 with rounded corners, to obtain an individual IC module 7 with the conductive adhesive layer 11 attached.

Then, the IC module 7 with the conductive adhesive layer 11 attached is embedded in the card base 2 with the recess 9 formed therein, and a predetermined heat block is pressed against the external connection terminal 71 to apply a predetermined heat pressure toward the card base 2 for a predetermined time. This melts the conductive adhesive layer 11 made of ACF, electrically connecting the terminals 73a and 73b of the IC module 7 to the first end 81 and second end 82 of the antenna 8, and mechanically connecting the IC module 7 to the card base 2. Although the heat pressure conditions for the ACF vary depending on the type and composition, as an example, the time can be 0.5 seconds or more and 10.0 seconds or less, the temperature can be 150°C or more and 250°C or less, and the pressure can be 20 MPa or more and 100 MPa or less.

(f) Regarding the Dual Interface Card of the First Embodiment To summarize the above, the dual interface card 1 of the first embodiment includes a card base 2 and an antenna 8 disposed inside the card base 2 and having at least a first end 81 and a second end 82, which are a plurality of ends. Furthermore, the dual interface card 1 includes an IC module 7 having an IC chip 74a and a plurality of terminals 73a and 73b electrically connected to the IC chip 74a. The IC module 7 is disposed in a recess 9 provided in the card base 2 such that the plurality of terminals 73a and 73b facing each other and the plurality of first ends 81 and second ends 82 are electrically connected to each other.

The first end 81 and the second end 82 are formed by a repeated folding structure of the antenna wire 83 constituting the antenna 8 from the outer periphery 97 of the recess 9 toward the center, and a part of them is exposed in the recess 9, i.e., the second recesses 92a and 92b. This increases the exposed area of the antenna wire 83 per unit area exposed in the recess 9, improving the reliability of the electrical connection between the terminals 73a and 73b of the IC module 7 and the antenna 8.

The second recesses 92a and 92b are formed deeper than the first recess 91, and the third recess 93 is formed deeper than the second recesses 92a and 92b.

As a result, when the IC module 7 is pressed against the card base 2 by applying heat and pressure, the depth of the second recess 92a can be determined as follows. That is, the depth is determined so that the distance between the terminal 73a, which is structured to protrude in a convex shape from the substrate 72 via the conductive adhesive layer 11, and the antenna wire 83 exposed at the bottom surface 92p of the second recess 92a is within an appropriate range for electrical connection. Also, in the region of the substrate 72 spaced apart from the terminal 73a along the Y-axis direction, the depth of the first recess 91 can be determined independently of the depth of the second recesses 92a and 92b so that the distance between the substrate 72 and the card base 2 is within an appropriate range for mechanical connection. However, the depth of the first recess 91 can be adjusted to be shallower than the depth of the second recesses 92a and 92b, taking into account at least the thickness of the terminal 73a.

The dual interface card 1 of this embodiment can therefore improve the reliability of both the electrical connection between the IC module 7 and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2. Even when the same conductive adhesive layer 11 is used, it is possible to achieve both the electrical connection between the IC module 7 and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2. Therefore, the dual interface card 1 of this embodiment can improve the reliability of both the electrical connection between the IC module and the antenna and the mechanical connection between the IC module and the card base, and can improve manufacturing efficiency.

2. Second Embodiment Next, a dual interface card according to a second embodiment of the present disclosure will be described.

Figure 5 is a diagram showing the configuration of the first end 81 and the second end 82 of the antenna 8 corresponding to Figure 1 (b) for the dual interface card 1a of the second embodiment. In the dual interface card 1a of this embodiment, the first exposed portions 86a and 87a of the first end 81 and the second end 82, which are the areas where the antenna wire 83 is actually exposed from the card base 2, are configured so that multiple sections of the antenna wire 83 are exposed discontinuously.

That is, the antenna wire 83 constituting the first end 81 and the second end 82 has a portion other than the bent portion of the folded structure exposed in the second recesses 94a and 94b. However, the bent portion of the folded structure, which is the end on the +Y direction side and the -Y direction side, overlaps with the first recess 91 in a plan view along the Z axis, and is embedded in the card base 2, which is on the -Z direction side of the bottom surface of the first recess 91. This is what makes it different from the dual interface card 1 of the first embodiment.

In the first recess 91, at least the bent portions of the folded structure of the antenna 8 of the first end 81 and the second end 82, which is a repeated folded structure from the outer periphery 97 of the recess 9 toward the center, are overlapped and not exposed by the antenna wire 83 constituting the antenna 8. In addition, in the second recesses 94a and 94b, the portions other than the bent portions are exposed. Note that the portions other than the bent portions are exposed so as to be lined up intermittently with each other.

At the first end 81, a covered region 84a where the bent portion of the folded structure of the antenna wire 83 is not exposed and overlaps with the first recess 91 is formed on the +Y direction side of the first exposed portion 86a formed in the second recess 94a. Also, on the -Y direction side of the first exposed portion 86a, a covered region 84b where the bent portion is not exposed and overlaps with the first recess 91 is formed. Similarly, covered regions 85a and 85b where the bent portion is not exposed and overlaps with the first recess 91 are formed on the +Y direction side and -Y direction side of the second exposed portion 87a at the second end 82.

In this embodiment, as in the first embodiment, the recess 9 formed for embedding the IC module 7 in the card base 2 includes a first recess 91, second recesses 94a and 94b, and a third recess 93. Here, FIG. 6(a) is a cross-section of the dual interface card 1a in FIG. 5 taken along line D-D, viewed from the -X direction, FIG. 6(a) shows a diagram with the IC module 7 omitted, and FIG. 6(b) shows a diagram of FIG. 6(a) with the IC module 7 mounted.

As shown in Figures 6(a) and 6(b), the first recess 91 of the recess 9 of the card base 2 is formed to overlap the end portions of the first end 81 of the antenna wire 83 on the -Y and +Y sides in a plan view along the Z axis. The overlapping portions are covered regions 84a and 84b in which the bent portion of the folded structure of the antenna wire 83 is covered by the core layer 5. On the other hand, in the second recess 94a of the recess 9, which is deeper than the first recess 91, the portion of the folded structure of the first end 81 of the antenna wire 83 other than the bent portion is exposed at the bottom surface 94p. In other words, the bare conductor is exposed without the core layer 5 or the covering of the covered conductor.

As shown in FIG. 5, the exposed portion of the first end 81 other than the bent portion arranged in the first exposed portion 86a of the folded structure extends along a straight line parallel to the Y axis along the side 97a of the outer periphery 97 of the recess 9. The center-to-center distance, i.e., pitch, of the zigzag-shaped antenna wire 83 of the adjacent portions excluding a part of the bent portion is substantially constant. The width of the entire first end 81 in the direction along the Y axis is W22, and the width of the second recess 92a where a part of the first end 81 overlaps in a plan view along the Z axis, i.e., the width of the first exposed portion 86a along the Y axis is W21. At this time, W22 is longer than W21. In other words, the value of W22 is greater than the value of W21 by the sum of the lengths of the covering regions 84a and 84b of the first end 81 along the Y axis. The above also applies to the second exposed portion 87a and the covered areas 85a and 85b at the second end 82.

In this embodiment, the dual interface card 1a can be manufactured in the same manner as in the first embodiment. Here, when the second recesses 94a and 94b are formed by cutting using a milling tool, the bent portions of the folded structure formed at the ends of the antenna wire 83 on the -Y and +Y sides are covered by the core layer 5 without exposing the entire first end 81 or the second end 82 from the bottom surface 94p. As described in the first embodiment, the antenna wire 83 is embedded in the core layer 5 while being subjected to heat and pressure by the winding machine, but in the region where the antenna wire 83 is exposed, only about half of the cross section of the antenna wire 83 is embedded in the core layer 5. At this time, the adhesive strength between the antenna wire 83 and the core layer 5 is lower than in the portion where the entire antenna wire 83 is embedded in the core layer 5.

In the dual interface card 1a of this embodiment, when the recess 9 is formed, the antenna wire 83 at the first end 81 or the second end 82 is not entirely exposed, and at least the bent portion of the antenna wire 83 at the first end 81 or the second end 82 is covered by the core layer 5. This makes it possible to prevent the exposed portion of the antenna wire 83 from peeling off from the core layer 5 during the cutting process when the recess 9 is formed. In addition, the covered regions 84a, 84b, 85a, and 85b where the antenna wire 83 at the first end 81 or the second end 82 is covered by the core layer 5 are limited to the narrow regions that are the bent portions of the first end 81 or the second end 82. This makes it possible to secure a sufficient area for the first exposed portions 86a and 87a for electrical connection with the terminals 73a and 73b of the IC module 7, and to achieve good electrical connection between the IC module 7 and the antenna 8.

Here, if the covered regions 84a and 84b corresponding to the first end 81 are provided with equal sizes, and the length of each of the covered regions 84a and 84b along the Y axis is Wc2, then Wc2 = (W22 - W21)/2. The value of Wc2 is preferably 2% or more and 20% or less of the value of W22, and more preferably 5% or more and 15% or less.

By setting the width in the former range, peeling of the exposed antenna wire 83 from the core layer 5 during cutting can be suppressed, while maintaining good electrical connection between the IC module 7 and the antenna 8 even when the cutting position of the second recesses 94a, 94b or the mounting position of the IC module 7 are shifted. By setting the width in the latter range, peeling of the antenna wire 83 from the core layer 5 can be further suppressed, and the effect of absorbing misalignment in processing and mounting position can be further improved, and costs can be reduced by suppressing unnecessary wiring of the antenna wire 83 that is not involved in the electrical connection.

3. Third Embodiment Next, a dual interface card according to a third embodiment of the present disclosure will be described.

Figure 7(a) is a diagram showing the configuration of the first end 81a and the second end 82a of the antenna 8 corresponding to Figure 1(b) for the dual interface card 1b of the third embodiment. Figure 7(b) is a diagram extracting the configuration of the antenna wire 83 near the first end 81a of Figure 7(a). In the dual interface card 1b of this embodiment, the first end 81a and the second end 82a are formed by a repeated folding structure of the antenna wire 83 constituting the antenna 8 from the outer periphery 97 of the recess 9 toward the center. Furthermore, a part of it is exposed in the recess 9, and the part of the antenna 8 other than the bent part of the folding structure is inclined with respect to a straight line along the outer periphery 97.

The bent portion of the folded structure where the antenna wire 83 is exposed among the first end 81a and the second end 82a is the first exposed portion 86b and the second exposed portion 87b that overlap the second recesses 95a and 95b in a plan view along the Z-axis direction. On the other hand, the area other than the bent portion where the antenna wire 83 is covered by the core layer 5 is the covered regions 84c, 84d and 85c, 85d that overlap the first recess 91 in a plan view. The covered regions 84c and 84d are located on the +Y and -Y sides of the first exposed portion 86b, and the covered regions 85c and 85d are located on the +Y and -Y sides of the second exposed portion 87b. That is, the first end 81a and the second end 82a are similar to the second embodiment in that they include the covered regions 84c, 84d and 85c, 85d.

At the first end 81a and the second end 82a of the antenna wire 83, the portions other than the bent portions at the upper and lower ends of the folded structure are inclined obliquely with respect to the straight lines m1 and m2 parallel to the sides 97a and 97b along the outer periphery 97 of the first recess 91 and the second recesses 95a, 95b, respectively, that is, the straight line parallel to the Y axis. Furthermore, the first end 81a and the second end 82a are formed to follow the outline of a rectangle whose width along the X-axis direction is W31 and whose width along the Y-axis direction is W22.

When the recess 9, whose outer peripheral shape is substantially the same as that of the IC module 7, is formed by cutting, the method of cutting and forming the second recesses 95a and 95b while exposing the antenna wire 83 is as described above. That is, only the second recess 95a may be cut while moving the milling tool counterclockwise or clockwise, and then only the second recess 95b may be cut in the same manner. Alternatively, the milling tool may be moved left and right across the second recesses 95a and 95b, and cutting may be performed continuously while shifting the tool from top to bottom in sequence, to form the second recesses 95a and 95b simultaneously.

When the former method is used, the milling tool cuts either the second recess 92a or 92b while moving in the direction along the X-axis and the direction along the Y-axis. If the wiring direction of the antenna wire 83 and the moving direction of the milling tool are approximately parallel, cutting the antenna wire 83 in the middle may cause a part of the antenna wire 83 to branch out and produce unintended branches, which may lead to the occurrence of whiskers. However, in this embodiment, the above-mentioned problem can be suppressed by tilting the parts of the folded structure of the first end 81a and the second end 82a other than the bent parts at the upper and lower ends.

In addition, at the first end 81a, the portion other than the bent portion of the folded structure is inclined clockwise by a predetermined angle θ with respect to the Y axis, which is a straight line along the side 97a of the outer periphery 97 of the recess 9. Here, the inclination angle θ is preferably 2 degrees or more and 20 degrees or less, and more preferably 5 degrees or more and 15 degrees or less. Furthermore, the inclination angle θ does not need to be strictly the same in all portions other than the bent portion of the folded structure, and may vary within the above-mentioned range. By setting the inclination angle θ in the former range, the antenna wire 83 has an inclination with respect to the direction along the X axis or Y axis, which is the movement direction of the end mill when cutting the recess 9, and therefore the problem of the antenna wire 83 being unintentionally branched can be suppressed.

On the other hand, by setting the inclination angle θ in the latter range, it is possible to further suppress the occurrence of whiskers, which are branches of the antenna wire 83. Also, even if the end on the +X direction side of the first end 81a is located on the +X direction side of the boundary between the first recess 91 and the second recess 95a and the third recess 93, it is possible to further reduce the area of the antenna wire 83 that is broken when the antenna wire 83 is cut when the third recess 93 is cut. This further improves the reliability of the electrical connection between the antenna 8 and the terminal 73a of the IC module 7.

In this embodiment, the end of the first end 81a in the region along the X-axis direction on the +X side is approximately the same position as the boundary between the second recess 95a and the third recess 93, and the end on the -X side is on the -X side of the end of the second recess 95a, which is the outer periphery 97 of the recess 9. In this way, if the end on the +X side of the first end 81a is approximately the same position as the boundary between the second recess 95a and the third recess 93, or is on the -X side of this, the antenna wire 83 is not cut when cutting the third recess 93, or the amount of cutting of the antenna wire 83 can be reduced. This makes it possible to suppress branching of the antenna wire 83, that is, the occurrence of whiskers, which is more likely to occur the deeper the cutting depth is.

In addition, if the end of the first end 81a on the +X direction side is located on the +X direction side of the boundary between the first recess 91 and the second recess 95a and the third recess 93, the antenna wire 83 is cut when the third recess 93 is cut, and the antenna wire 83 is cut and broken in the middle. However, if the inclination angle θ is within the above-mentioned range, the broken area of the antenna wire 83 can be reduced, and a reliable electrical connection between the antenna 8 and the terminal 73a of the IC module 7 can be achieved. Furthermore, if the end of the first end 81a on the +X direction side is located on the +X direction side of the boundary between the first recess 91 and the second recess 95a and the third recess 93, it is preferable to arrange the antenna wire 83 so that this area includes the bent part of the folded structure and does not include any part other than the bent part. In this way, when the third recess 93 is cut, the antenna wire 83 is less likely to branch from the bent part that is significantly angled from the direction along the Y axis, which is the movement direction of the end mill, and this ultimately contributes to improving quality.

In addition, in the second end 82a, the portion other than the bent portion of the folded structure is inclined counterclockwise in the opposite direction to the first end 81a by a predetermined angle θ with respect to the Y axis, which is a straight line along the side 97b of the outer periphery 97 of the recess 9. Here, the range of the inclination angle θ is the same as that of the first end 81a, except that the direction is reversed. The inclination of the portion other than the bent portion of the first end 81a with respect to the straight line along the outer periphery 97 and the inclination of the portion other than the bent portion of the second end 82a with respect to the straight line along the outer periphery 97 are formed line-symmetrically with each other. In other words, the first end 81a and the second end 82a are arranged symmetrically with respect to the axis along the Y axis as a whole configuration, including the inclination of the portion other than the bent portion of the antenna wire 83.

In this way, the inclination of the portion of the first end 81a other than the bent portion and the inclination of the portion of the second end 82a other than the bent portion are arranged in a line-symmetrical relationship with each other. As a result, when the antenna wire 83 is embedded in the core layer 5 to form the antenna sheet 12, the distortion and internal stress of the core layer 5 are offset and dispersed, making it possible to obtain a uniform antenna sheet 12 with less distortion and internal stress.

When embedding the IC module 7 in the recess 9, the heat pressure conditions applied between the first end 81a and the terminal 73a and the heat pressure conditions applied between the second end 82a and the terminal 73b are symmetrical to each other. This prevents bias in the heat pressure conditions and stabilizes the electrical connection between the IC module 7 and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2.

However, the inclination of the first end 81a with respect to a straight line along the outer periphery 97 of the portion other than the bent portion and the inclination of the second end 82a with respect to a straight line along the outer periphery 97 of the portion other than the bent portion may be the same, rather than being line-symmetrical. In other words, the configuration of the antenna wire 83 of the second end 82a may be substantially the same as the configuration of the antenna wire 83 of the first end 81a, but moved parallel to the +X direction. In this case, the effects and advantages of the configuration of the first end 81a described above also apply to the second end 82a.

4. Fourth Embodiment Next, a dual interface card according to a fourth embodiment of the present disclosure will be described.

Figure 8(a) is a diagram showing the configuration of the first end 81 and second end 82 of the antenna 8 corresponding to Figure 1(b) for the dual interface card 1c of the fourth embodiment. Figure 8(b) is a cross-sectional view of the dual interface card 1c of Figure 8(a) taken along line E-E, viewed from the -Y direction. Also, Figure 8(c) is a view of the IC module 7a viewed from the side of the substrate 72 opposite the external connection terminal 71.

In the dual interface card 1c of this embodiment, the first recesses located on the +Y and -Y sides of the recesses 9 of the dual interface card 1 of the first embodiment are also divided on the X-axis side. In addition, the recesses 9 are newly provided with fourth recesses 96a and 96b that are deeper than the first recesses and are located approximately in the center along the X-axis direction. This is what makes it different from the first embodiment.

The recess 9 includes a part of the outer periphery 97 and has first recesses 91a, 91b, 91c, and 91d that are separated and disposed at four locations on the +Y direction side and the -X direction side, the +Y direction side and the +X direction side, the -Y direction side and the -X direction side, and the -Y direction side and the +X direction side. The recess 9 also includes another part of the outer periphery 97 and has second recesses 92a and 92b that are separated from each other, and a third recess 93 that is adjacent to all of the first recesses 91a, 91b, 91c, and 91d and the second recesses 92a and 92b and is formed closer to the center than these.

In addition to these, the recess 9 further includes fourth recesses 96a and 96b that include part of the outer periphery 97 and are arranged separately on the +Y direction side and the -Y direction side adjacent to the third recess 93. The fourth recess 96a is formed at a position sandwiched between the first recesses 91a and 91b, and the fourth recess 96b is formed at a position sandwiched between the first recesses 91c and 91d. The fourth recesses 96a and 96b are formed deeper than the first recesses 91a, 91b, 91c, and 91d, and shallower than the third recess 93.

On the other hand, at a predetermined position on the surface of the substrate 72 that faces the fourth recesses 96a and 96b when mounted on the IC module 7a, a convex portion is formed with an area smaller than the area of the fourth recesses 96a and 96b when viewed in a plan view along the Z-axis direction. This is the lead portion 77 shown in Figures 8(b) and 8(c). The lead portion 77 functions as a lead wire that applies nickel plating or gold plating to improve durability and environmental resistance on the copper foil surface of the terminals 73a, 73b, etc., formed on the surface of the substrate 72 opposite the external connection terminal 71 of the IC module 7a, and that carries a current when inspecting the terminals.

As mentioned above, the IC modules 7a are usually formed as a module tape in which a large number of IC modules 7 are formed on a continuous long tape with one or two rows. The lead wires are then wired across the IC modules 7a so as to electrically connect the terminals 73a and 73b of each IC module 7a. Therefore, lead portions 77 remain as traces of the lead wires at the +Y and -Y ends of each individual IC module 7a that has been punched out into individual pieces.

The lead portion 77 is usually made of copper foil or the like, and thus has a certain degree of thickness, similar to the terminals 73a and 73b. Therefore, if the depth of the recess 9 facing the substrate 72 in the area where the lead portion 77 is present is uniformly the same, the conductive adhesive layer 11 is compressed by heat pressure according to the gap between the lead portion 77 and the card base 2. However, the gap between the substrate 72 and the card base 2 in the area where the lead portion 77 is not present becomes too large by the amount of the absence of the lead portion 77, and therefore it may not be possible to achieve a good mechanical connection between the IC module 7a and the card base 2 in this area.

In this embodiment, as shown in FIG. 8(b), a fourth recess 96a that is deeper than the other regions, such as the first recess 91a, is further formed in the region of the card base 2 facing the lead portion 77. This makes it possible to optimize the gap between the IC module 7 and the card base 2 in the region where the lead portion 77 is present, and the gap between the IC module 7 and the card base 2 in the region where the lead portion 77 is not present. As a result, it is possible to achieve a stable mechanical connection overall between the IC module 7 and the card base 2 while suppressing a decrease in adhesive strength in specific locations. The same applies to the fourth recess 96b.

When the thickness of the lead portion 77 is 0.015 mm or more and 0.15 mm or less, it is preferable that the difference between the depth of the fourth recesses 96a, 96b and the depth of the first recesses 91a, 91b, 91c, 91d is approximately 0.005 mm or more and 0.2 mm or less. It is even more preferable that the difference is 40% or more and 120% or less of the thickness of the lead portion 77. This is because the above-mentioned effects can be further improved by being in such a range.

In this embodiment, the lead portions 77 are described as being provided in two locations along the Y axis, i.e., in the vertical direction, on the surface of the substrate 72 opposite the external connection terminals 71 of the IC module 7a. However, the arrangement of the lead portions 77 is not limited to this, and they may be provided in two locations along the X axis, i.e., in the horizontal direction, on the surface of the substrate 72 opposite the external connection terminals 71 of the IC module 7a. Furthermore, any number of lead portions can be provided at any location along the outer periphery 97 of the IC module 7a. This is because the above-mentioned effects can be obtained by providing the necessary fourth recesses in the card base 2 according to the arrangement and number of lead portions 77 provided on these IC modules 7a.

The above-described embodiments and variations of the present disclosure may be combined in whole or in part with each other, provided no inconsistencies arise, and such combinations are naturally included in the present disclosure.

1, 1a, 1b, 1c Dual interface card 2 Card base 3, 6 Oversheet layer 4, 5 Core layer 7, 7a IC module 8 Antenna 9 Recess 11 Conductive adhesive layer 11a Conductive particles 11b Adhesive 12 Antenna sheet 71 External connection terminal 72 Substrate 73a, 73b Terminal 74 IC chip body 74a IC chip 74b Molded portion 74p Pad 75 Wire 76 Bonding hole 77 Lead portion 81, 81a First end portion 82, 82a Second end portion 83 Antenna line 84a, 84b, 84c, 84d, 85a, 85b, 85c, 85d Covered region 86, 86a, 86b First exposed portion 87, 87a, 87b Second exposed portion 91, 91a, 91b, 91c, 91d First recesses 92a, 92b, 94a, 94b, 95a, 95b Second recesses 92p, 94p Bottom surface 93 Third recesses 96a, 96b Fourth recess 97 Outer periphery 97a, 97b Side

Claims (9)

A dual interface card capable of contact and non-contact communication with an external device,
A card base;
an antenna having a plurality of ends disposed within the card base;
an IC module having an IC chip and a plurality of terminals electrically connected to the IC chip;
the IC module is disposed in a recess provided in the card base such that the terminals and the ends facing each other are electrically connected to each other;
the plurality of ends are formed by a repeated folding structure of an antenna wire constituting the antenna from the outer periphery toward the center of the recess, and a part of the structure is exposed in the recess;
The recess includes a first recess that includes a portion of the outer periphery and is separated from the first recess;
a second recess including another part of the outer periphery and separated from the other recess;
a third recess portion formed adjacent to all of the first recess portion and the second recess portion and toward the center thereof;
At least a portion of the ends is exposed in the second recess,
The second recess is deeper than the first recess, and the third recess is deeper than the second recess. The dual interface card according to claim 1, wherein the second recess has a structure in which the antenna wires constituting the antennas at the multiple ends are repeatedly folded from the outer periphery of the recess toward the center, and the structure is continuously exposed. In the first recess, at least a bent portion of the folded structure of the antenna is overlapped without being exposed, among a repeated folded structure from an outer periphery of the recess toward a center thereof by an antenna wire constituting the antenna at the plurality of ends,
The dual interface card according to claim 1 , wherein a portion other than the bent portion is exposed in the second recess. The dual interface card according to any one of claims 1 to 3, wherein the IC module has the multiple terminals and multiple ends that face each other electrically connected via an anisotropic conductive film. The dual interface card according to claim 4, wherein the anisotropic conductive film is arranged to overlap the first recess and the second recess. The dual interface card according to any one of claims 1 to 5, wherein the outer periphery is a substantially rectangular shape having sides substantially parallel to the short and long sides of the card body, and the multiple ends are configured by a repeated folding structure from the outer periphery, which is a side of the recess substantially parallel to the short side of the card body, toward the center by an antenna wire constituting the antenna. The dual interface card according to any one of claims 1 to 6, wherein the portion of the antenna other than the bent portion of the folded structure is inclined with respect to a straight line along the outer periphery. The recess further includes a fourth recess including a part of the outer periphery and adjacent to the third recess,
The fourth recess is formed deeper than the first recess and shallower than the third recess,
8. The dual interface card according to claim 1, wherein a convex portion having an area smaller than the fourth concave portion is formed on a surface of the IC module facing the fourth concave portion. A method for manufacturing a dual interface card capable of contact communication and non-contact communication with an external device, comprising:
an antenna forming step of embedding an antenna wire into a first base material while applying heat and pressure to form an antenna having a plurality of ends on one surface of the first base material;
a lamination step of laminating a second base material on the first base material on which the antenna is formed so as to sandwich the antenna;
a punching step of punching a laminate in which the first base material and the second base material are laminated into a card base of a card size;
a recess forming step of forming a recess in the card base for embedding an IC module;
an IC module preparation step of preparing an IC module having an IC chip and a plurality of terminals electrically connected to the IC chip;
an IC module bonding step of bonding the IC module to the recess of the card base via a conductive adhesive layer so that the plurality of terminals and the plurality of end portions facing each other are electrically connected,
the plurality of ends are formed by a repeated folding structure of an antenna wire constituting the antenna from the outer periphery toward the center of the recess, and a part of the structure is exposed in the recess;
The recess includes a first recess that includes a portion of the outer periphery and is separated from the first recess;
a second recess including another part of the outer periphery and separated from the other recess;
a third recess portion formed adjacent to all of the first recess portion and the second recess portion and toward the center thereof;
At least a portion of the ends is exposed in the second recess,
A method for manufacturing a dual interface card, the second recess being formed deeper than the first recess, and the third recess being formed deeper than the second recess.