JPH0416836B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an IC card in which a chip mounting board in which an IC chip is mounted on an insulating board and a cover sheet for protecting the chip mounting board are fused together.

[Technical background of the invention and its problems] Conventionally, magnetic stripes have been applied to the surface of a card base material made of synthetic resin such as vinyl chloride resin as data cards for proof of money withdrawals and withdrawals at financial institutions. So-called magnetic cards, which are coated with magnetic stripes and have various data such as account numbers and password numbers magnetically recorded, are widely used.

This magnetic card has a simple structure and high durability.
Moreover, since it is suitable for mass production, it is widely used in the service industry.

However, such magnetic cards have a small information storage capacity, so they can only record a small amount of information such as account numbers and PIN numbers.
Therefore, to record various types of information such as records of deposits and withdrawals, it is necessary to set up a separate ledger like a bankbook in a financial institution, which has been an obstacle to increasing the efficiency of information processing.

Furthermore, since information on this magnetic card can be read relatively easily from the outside, there have been problems in maintaining airtightness and preventing theft.

Under these circumstances, data cards called IC cards are being developed in recent years, which have a storage element and its control element built into the card to dramatically improve its information storage capacity.

This IC card has an IC chip that stores and processes information mounted inside a card board made of electrically insulating synthetic resin, and has input/output terminals exposed from the surface of the card.It is installed in financial institutions, etc. By setting it in the card processing section of a card reader/writer, the input/output terminals in the card processing section and the input/output terminals of the IC card are electrically connected.
This allows information to be written to or read from the built-in IC chip.

The above-mentioned IC card is manufactured by forming a conductor pattern 1a and an input/output terminal 1b on the surface of an insulating substrate 1 made of synthetic resin by a well-known printing method, a photographic method, etc., as shown in FIG. 1, for example.
On both the front and back sides of an IC circuit board A, which is equipped with IC chips 2 and 3 and electrically connected to them,
It is manufactured by arranging a front cover sheet 4 and a back cover sheet 5 made of vinyl chloride resin, and press-molding them to integrate them as shown in FIG.

Note that a through hole 4a is bored in the front cover sheet 4, and during press molding, an input/output terminal 1b is fitted into the through hole 4a, and the top thereof is used as an electrode for external connection.

By the way, in an IC card constructed in this way, the IC chip protrudes from the surface of the insulating plate, so uneven pressure is applied to the IC chip during press processing, causing the conductor pattern to break or break.
The IC chip may be damaged.

Therefore, in order to solve this problem, a method can be considered in which the IC chip is embedded in an insulating substrate, and the exposed surface is made to be on the same level as the surface of the insulating plate, and then press molding is performed.

To do this, a recess with a shape and size that allows the IC chip to fit is formed in advance on the insulating substrate, and after the IC chip is fitted into the recess and a predetermined electrical connection is made, the insulating substrate is A possible method is to fuse the cover sheet from both sides.

In this method, the shape of the opening of the recess,
If the size and depth are exactly the same as the cross-sectional shape and thickness of the IC chip, it will be difficult to fit the IC chip into the area, so a slight gap will be provided between the recess and the IC chip. .

However, if a gap is provided between the recess and the IC chip in this way, the conductor pattern 1a
Since the connecting portions with the IC chips 2 and 3 will be floating above this gap, there is a risk that the connecting portions will be damaged by the pressure of press molding when the cover sheets 4 and 5 are fused together.

[Object of the Invention] The present invention has been made in response to the above-mentioned circumstances.
A cover sheet is fused to a chip mounting board on which an IC chip is fixed and the specified electrical connections are made.
The purpose of the present invention is to provide an IC card in which the electrical connection between an IC chip and a conductor pattern is not damaged during press processing.

[Summary of the Invention] That is, the IC card of the present invention has a conductive pattern formed on its surface, a recessed portion having a depth approximately the same as the thickness of the IC chip to be mounted, and a concave portion formed between the exposed surface of the IC chip and the conductive pattern. an insulating substrate on which the IC chip is mounted in the recess so that the IC chips are on the same plane;
The bottom part between the IC chip and the recessed part is filled,
The conductor pattern and the
Insulating filling material that prevents damage to the IC chip connections,
and a cover sheet laminated on the insulating substrate.

[Embodiment of the Invention] FIG. 3 is a cross-sectional view showing the configuration of essential parts of an embodiment of the IC card of the present invention.

In the following figures, parts common to those in FIGS. 1 and 2 are designated by the same reference numerals.

The IC card in this embodiment is constructed by placing a front cover sheet 4 and a back cover sheet 5 on both sides of a central chip mounting board A, which are fused together by press processing. .

The insulating substrate 1, which is the base of the chip mounting board A in the center, is formed with a recess 1c into which the IC chip 2 can be loosely fitted so that its exposed surface is on the same level as the board surface. It is fixed to the bottom of the concave portion 1c. The concave portion 1c may be formed, for example, by applying a photosensitive resin onto the insulating substrate 1 and using a photoresist method, by pressing a heated mold, or by punching into the shape of the concave portion. A processed sheet can be bonded onto another sheet.

The gap between the IC chip 2 and the recessed portion 1c is filled with an insulating filler 6 such as epoxy resin, silicone rubber, or a foaming composition, and is cured.

Furthermore, a conductor pattern 1a is formed on the insulating substrate 1, and the conductor pattern 1a and the inner leads of the IC chip 2 are electrically connected in a predetermined manner.

The electrical connection between the conductive pattern 1a and the IC chip 2 can be made by forming the conductive pattern 1a from the inner pad of the IC chip 2 onto the insulating substrate 1 after the IC chip 2 is fixed to the recess 1c of the insulating substrate 1, or by forming the conductive pattern 1a in advance. A conductive pattern 1a is formed on an insulating substrate 1a, and after the IC chip 2 is fixed in the recessed part 1c, a conductive paste is applied to connect the conductive pattern and the inner pad of the IC chip 2. It is done.

Input/output terminals 1b are provided on the conductor pattern 1a to protrude in a direction perpendicular to the plate surface of the insulating substrate 1. .
The thickness of the input/output terminal 1b is approximately the same as the thickness of the front cover sheet 2.

In an IC card configured in this way, pressing is performed with the IC chip 2 buried in the insulating substrate 1 so that its exposed surface is at the same level as the board surface, so the pressure during pressing is Since the insulating filler 6 is applied evenly to the board surface and is filled between the IC chip 2 and the side wall of the concave portion 1c of the insulating substrate 1, the IC chip 2 and the conductor pattern 1a are filled with the insulating filler 6. The electrical connection between them will be protected by this insulating filler 6 and will not be damaged by press working.

FIG. 4 is a cross-sectional view showing another embodiment of the present invention.

In this embodiment, instead of filling the spaces between the IC chips 2 and 3 and the recessed portion 1c with a hardening insulating filler 6, a conductive pattern is formed on the insulating substrate 1 to connect the inner pads of the IC chips and the electrical connection. After the electrical connection is made, an insulating sheet 7 is pasted to cover this gap and span between the IC chips 2, 3 and the insulating substrate 1 to protect the conductor portion from the pressure during pressing.

In addition, in the present invention, it is also possible to omit the back cover sheet 5 by making the insulating substrate 1 thicker. .

[Effects of the Invention] As explained above, the IC card of the present invention has a concave portion formed in the IC chip mounting portion of the insulating substrate,
In an IC card using a chip mounting board with an IC chip fixed to the recess, the gap between the recess and the IC chip is filled or covered with an insulating sealing member, so that when the cover sheet is fused, the gap between the recess and the IC chip is filled or covered. Therefore, the electrical connection between the IC chip and the conductor pattern is not damaged.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view showing the structure of a commonly used IC card, Fig. 2 is a cross-sectional view thereof, Fig. 3 is a partial cross-sectional view showing an embodiment of the present invention, and Fig. 4 FIG. 3 is a partial cross-sectional view showing another embodiment of the present invention. A...Chip mounting board, 1...Insulating board, 1a
...Conductor pattern, 1b...Input/output terminal, 1c...
... Concave portion, 2, 3... IC chip, 4... Front cover sheet, 5... Back cover sheet, 6... Insulating filler, 7... Insulating sheet.

Claims (1)

[Claims] 1. A conductor pattern is formed on the surface and should be mounted.
A recessed portion having a depth approximately equal to the thickness of the IC chip is formed in the recessed portion so that the exposed surface of the IC chip and the conductive pattern are on the same plane.
Damage to the insulating substrate on which the IC chip is mounted, and the connecting portion between the conductive pattern and the IC chip during press molding due to filling in the space between the IC chip mounted in the recess and the recess. An IC card comprising: an insulating filler that prevents damage; and a cover sheet laminated on the insulating substrate.