JP2002074309A - IC card - Google Patents

Abstract

(57) [Summary] [Problem] A highly reliable IC for preventing disconnection inside a card
The card is provided at low manufacturing cost and low card thickness. A side end of a reinforcing plate disposed above an IC chip inside an IC card, or an IC chip itself is disposed outside a sealant. By arranging the reinforcing plate side end or the IC chip itself outside the sealant,
Disperses the stress generated inside the card when a pressing load is applied to the IC card. This reduces the shear stress generated in the wiring existing inside the card, and prevents disconnection without increasing the card thickness or manufacturing cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card having an IC module therein. In particular, it relates to a reinforcing structure provided inside an IC card.

[0002]

2. Description of the Related Art At present, as a card capable of storing and recording, a magnetic card system for performing magnetic storage and an IC card system for incorporating an IC module inside the card and storing data by an IC memory are generally used. Of these, IC
The card system has a larger storage capacity than the magnetic card system, and is much stronger than the magnetic card in terms of security such as forgery prevention. Due to these features, the IC card system is not limited to applications where magnetic card systems have been adopted, such as commuter passes and telephone cards,
It can be used in applications requiring higher security, such as electronic money and employee ID cards. But,
While magnetic cards are extremely thin and cost-effective, IC cards have built-in IC modules inside the cards, so that the card thickness is increased and portability is deteriorated, and manufacturing costs are increased. Is a problem, and IC
There is a strong demand for thinner cards and lower costs. On the other hand, in order to use the IC card for electronic money and the like, the reliability cannot be reduced by reducing the thickness and cost.

Since an IC card is used by an unspecified number of users, various external forces act on the IC card during use and portability, and the external force generates stress on an IC chip inside the card. . In particular, in the case of a thin card, since the external force exerts a great influence on the IC chip, a large stress is generated in the chip, which may cause the chip to be damaged. Therefore, when the thickness of the IC card is reduced, a reinforcing mechanism for protecting the IC chip against various external forces is used. As a reinforcing mechanism of an IC chip, a method of bonding a reinforcing plate to one or both sides of an IC chip mounting portion as in, for example, Japanese Patent Application Laid-Open No. 9-263082, or a method as in, for example, Japanese Patent Application Laid-Open No. 11-11061, A method of disposing a reinforcing member around an IC chip has been considered.

[0004]

FIG. 6 is a side sectional view showing a general structure of an IC card having a reinforcing plate inside the card. In a general IC card, first, the wiring 12 is provided on the surface of the substrate 18. And substrate 1
The terminals of the IC chip 13 mounted on the wiring 8 are bonded to the wiring 12 via a conductive material, and are sealed with a sealing material 15. On the upper surface of the IC chip 13, the strong supplementary plate 11 is disposed via an adhesive. By arranging these between the surface plates 16 and 17 and filling the adhesive 11, an IC card is configured. By arranging the reinforcing plate inside the card in this manner, the stress generated in the IC chip is reduced, and the IC chip can be protected. However, the protection of the IC chip itself does not necessarily eliminate the malfunction of the card.

In the card having the above structure, when a strong pressing load is applied from the upper or lower surface of the card,
The IC chip itself is protected by the reinforcing plate. But,
The wiring connecting the IC chip terminal to the antenna coil or the input / output device may be broken at a portion corresponding to the interface between the sealant and the adhesive, and the card may malfunction. This is because the stress generated in the reinforcing plate by the pressing load mainly acts on the wiring under the sealant through the sealant, while the stress transmission to the adhesive portion is relatively small, This is because the stress transmitted to the wiring becomes extremely small, so that a large shear stress is generated in the wiring near the interface between the sealant and the adhesive to cause disconnection. In particular, in the wiring of a thin IC card, silver foil or the like is often used by being printed on a substrate in order to reduce the thickness or to reduce the cost in manufacturing and to improve workability, and prevention of disconnection due to shear force is a serious problem.

An increase in the cross-sectional area of wiring is effective in preventing disconnection due to shearing force. However, an increase in the cross-sectional area of wiring in an IC card causes an increase in card manufacturing cost and makes the card itself thick and inconvenient to carry. Becomes Further, it is conceivable that the smoothness of the card surface is lost, thereby causing problems in usability and design. Although it is conceivable to avoid disconnection by using a lead frame, this method is inferior to the method using silver foil in terms of card thickness, smoothness, manufacturing cost, workability, and the like.

An object of the present invention is to provide a highly reliable IC card capable of preventing disconnection without increasing the cross-sectional area of wiring such as silver foil without increasing the manufacturing cost and card thickness. To provide.

[0008]

The above object is achieved by disposing a part of an IC chip reinforcing plate provided inside an IC card outside a sealant of the IC chip.

According to the present invention, when a pressing load is applied to the card, the stress transmitted through the reinforcing plate is transmitted not only to the sealant but also to the adhesive. As a result, generation of large shear stress at the interface between the wiring below the sealant and the wiring below the adhesive can be suppressed, and disconnection can be prevented. Further, when this means is used, there is no need to change the thickness of the reinforcing plate, so that the card thickness does not increase. In addition, since it is not necessary to increase the cross-sectional area of the wiring or change the material, it is possible to suppress an increase in manufacturing cost.

As a known example of the shape of the IC chip reinforcing plate, there is a shape in which the thickness of the end portion is reduced.
However, the purpose of this example is to prevent the cover film from being damaged by the reinforcing plate, which is different from the purpose of the present invention, which is to prevent disconnection inside the IC card. Furthermore, in order to prevent disconnection, which is the object of the present invention, it is effective to place the reinforcing plate outside the chip or the sealant as in the present invention, instead of simply using a reinforcing plate having a thinner end portion. It is a target. From these points, the present invention is essentially different from the above-mentioned known examples.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

First, FIG. 1 shows an IC card according to a first embodiment of the present invention. 1 is a plan view and FIG. 2 is a side sectional view. In the following, non-contact I
The description will be made using a C card, but the present invention is not necessarily limited to a non-contact IC card, but also includes a contact IC card.

The IC card according to the present embodiment includes a substrate 1
8, wiring 12, IC chip 13, reinforcing plate 11, sealant 1
5, adhesive 14, surface plates 16 and 17, antenna coil 1
9 is provided. The substrate 18 is made of a thin and flexible synthetic resin such as PET. The wiring 12 is made of a conductive material such as silver foil on the substrate 1.
8 is provided by printing in a predetermined pattern on the surface of the antenna coil 8 and is electrically connected to the antenna coil 19. I above
The terminals of the C chip 13 are bonded to the wiring 12 via a sealant 15 which is an anisotropic conductor. A reinforcing plate 11 is adhered and fixed to the upper surface of the IC chip 13, and a slope is provided on an end side surface of the reinforcing plate, and the reinforcing plate 11 is formed to have an outward shape so that a part of the reinforcing plate is located outside the sealant. Are provided. That is, the reinforcing plate 11 forms a truncated cone, and the enlarged portion is located upward and the reduced portion is located downward in the figure. However, the shape of the reinforcing plate 11 is not limited to a truncated cone. The substrate 18, the wiring 12, the IC chip 13,
The reinforcing plate 11 and the sealant 15 are arranged between the upper and lower surface plates 16 and 17, and by filling the adhesive 14, the IC module can be protected and the surface can be made smooth. Here, the surface plates 16 and 17 are made of a thin and flexible synthetic resin such as PET.

In the IC card shown in FIG. 6 in which the reinforcing plate is not disposed outside the sealant, when a pressing load is applied to the card, a large shear stress is applied to the wiring near the interface between the sealant and the adhesive. This may cause disconnection. However, by arranging a part of the reinforcing plate outside the sealant as shown in FIG. 2, the transmission of stress from the reinforcing plate is performed not only to the sealant portion but also to the adhesive portion. As a result, the stress distribution is more dispersed, as compared with the structure shown in FIG. As a result, the shear stress generated in the wiring near the interface between the sealant and the adhesive can be reduced, so that disconnection can be prevented and the reliability of the IC card can be improved. Further, according to the present invention, it is not necessary to increase the cross-sectional area of the wiring or to change the material in order to prevent disconnection, so that it is possible to suppress an increase in manufacturing and material costs. Further, since there is no need to change the thickness of the reinforcing plate or other members, it is possible to prevent the thickness of the IC card from increasing.

Although a substrate is provided separately from the surface plate in FIG. 2, the surface plate itself can be used as the substrate. Although the chip and the reinforcing plate are directly bonded in FIG. 2, another material may be interposed therebetween. Further, FIG.
Although the reinforcement plate is placed outside the sealant by providing a slope at the reinforcement plate side end, the reinforcement plate is formed by making the side end stepped or curved, or making the entire reinforcement plate longer. May be arranged outside the sealant. Although the reinforcing plate is shown in FIG. 1 as having a substantially square shape, the reinforcing plate in the present invention is not limited to a substantially square shape, and may have any shape such as a circle, an ellipse, and a rectangle.

FIG. 3 shows the shear stress generated in the wiring immediately below the interface between the sealant and the adhesive when a pressing load is applied to the IC card shown in FIG. 1 at the end of the reinforcing plate as shown in FIG. The analysis results are shown for the case where a slope of 45 ° is provided at the side end portion and the case where no slope is provided and the reinforcing plate is not present outside the sealant as shown in FIG. Assuming that the value of the shear stress generated in the wiring when no gradient is provided is 1, the stress value when the gradient is provided and the reinforcing plate is arranged outside the sealant is 0.2.
6 shows that the shear stress is reduced to about 1/4, which indicates that the present invention is effective for preventing disconnection inside the IC card.

Next, as a second embodiment of the present invention, an embodiment of an IC card having no reinforcing plate inside the card will be described. FIG. 4 is a cross-sectional side view of the IC card in this embodiment. The IC card according to the present embodiment includes a substrate 18, wiring 12, IC chip 13, sealant 15, adhesive 14, surface plates 16 and 17, and antenna coil 19. The wiring 1 printed on the surface of the substrate 18 through the terminal of the IC chip 13 via the sealant 15 which is an anisotropic conductor
2 to form an IC module by bonding to the IC chip 1,
3 The chip upper surface and the surface plate 17 do not have the reinforcing plate 11 on the upper surface.
There is an adhesive between them. The IC chip itself has a reinforcing structure (means), the IC chip itself is formed thick (may be thinner than the thickness obtained by adding the reinforcing plate to the IC chip), and the IC chip is cut into a trapezoidal shape and the chip side surface is cut. This embodiment differs from the first embodiment in that a gradient is provided in the first embodiment. In an IC card having a structure without a reinforcing plate as in this embodiment, an IC card
By providing a gradient in the side surface shape of the chip itself, disconnection can be prevented. In an IC card having a structure in which a slope is provided on the side of the IC chip, when a pressing load is applied to the IC card from the upper surface or the lower surface, the stress generated in the IC chip is transmitted to the wiring below the sealant via the sealant. In addition to the above, the power is also transmitted to the wiring below the adhesive via the adhesive as compared with the case where there is no gradient.
As a result, disconnection can be prevented by reducing the shear stress generated in the wiring near the interface between the sealant and the adhesive.
It is possible to improve the reliability of the C card. In addition,
In this embodiment, similarly to the first embodiment, the shape of the chip side surface is not limited to a straight line, but may be a curve or a stepped shape.

According to these embodiments, there is provided an IC card in which reinforcing means for reinforcing the IC chip is provided, and a part of the reinforcing means is located outside the IC chip or the sealant of the IC chip. Is done.

Next, as a third embodiment of the present invention, an IC
An embodiment in the case of mounting by a chip or a wire bonding method will be described. FIG. 5 is a side sectional view of an IC card using the wire bonding method. This embodiment is basically the same as the example shown in FIG. 1, except that an IC chip 13 is arranged on a substrate 18 so that the terminals are on top, and the wires 41 are used to connect the IC chip terminals to the wiring 12. It is configured to be conductive. The IC chip and the wires are sealed by a non-conductive sealant 15, and a reinforcing plate 11 for reinforcing the IC chip is provided above the sealant.
By providing a slope or the like at one end, a part of the reinforcing plate is disposed outside the sealant. Even in a structure in which an IC chip is mounted by a wire bonding method, when a reinforcing plate disposed only inside the sealant is used, a wire near the interface between the sealant and the adhesive is disconnected due to a shearing stress due to a pressing load. There is fear. Therefore, by providing a part of the reinforcing plate outside the sealant as shown in this embodiment, the shear stress generated in the wiring near the interface between the sealant and the adhesive can be reduced, and disconnection can be prevented.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof.

[0021]

According to the present invention, the IC inside the IC card is
By providing the chip reinforcing plate or the IC chip itself outside the sealant, even if a large pressing load is applied to the card, the shear stress generated in the wiring inside the card is reduced and disconnection is prevented. Can be. Therefore, a highly reliable IC card can be provided without increasing the thickness and manufacturing cost of the IC card.

[Brief description of the drawings]

FIG. 1 is a plan view of an IC card according to an embodiment of the present invention.

FIG. 2 is a side sectional view of FIG.

FIG. 3 is a diagram illustrating a relationship between a shape of a reinforcing plate side end and a shear stress generated in a wiring according to the present invention.

FIG. 4 is a sectional view showing a part of an IC card according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a part of an IC card according to a third embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a part of a general IC card.

[Explanation of symbols]

11 ... reinforcing plate, 12 ... wiring, 13 ... IC chip, 14 ...
Adhesive, 15: sealant, 16, 17: surface plate, 18: substrate, 19: antenna coil, 41: wire.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Sasaki, 502, Kandachicho, Tsuchiura-city, Ibaraki Pref. Machinery Research Laboratories, Hitachi, Ltd. Ryozo Yoshino 1 in Horiyamashita, Hadano City, Kanagawa Prefecture F-term (reference) 2C005 MA10 MA15 MA18 MB01 MB10 NA08 NB03 NB34 PA25 5B035 AA08 BA05 BB09 BC00 CA03

Claims (3)

[Claims] An IC card having an IC chip and a reinforcing plate for reinforcing the IC chip inside the card, wherein at least a part of the reinforcing plate is an IC chip or an IC.
An IC card characterized in that it is located outside of a chip sealant. 2. An IC card having an IC chip inside the card, wherein at least a part of the IC chip is provided with a gradient so as to be located outside a sealant of the IC chip. . 3. An IC card having an IC chip inside the card, wherein reinforcing means for reinforcing the IC chip is provided.
A gradient is provided in a part of the reinforcing means, and an IC chip or I
An IC card characterized by being located outside of a sealant of a C chip.