JPH0755592B2 - Printed wiring board for IC card - Google Patents

Description

The present invention relates to a printed wiring board for an IC card, and particularly to an IC characterized in that contact terminals are formed by plating.
The present invention relates to a printed wiring board for a card.

(Prior Art) IC cards are expected to be used widely as so-called bank cards, recognition cards, health management cards, etc., but as they are handled by humans only, as their name implies Must be in the form of a card. Of course, this IC card has a printed wiring board on which electronic parts capable of recording various data are mounted, and the printed wiring board for the IC card can be made into various resin sheets. It is formed as an IC card by laminating it with the like.

In other words, since the IC card has a built-in printed wiring board for IC cards and is handled as a so-called card, the printed wiring board for IC cards that is built in the IC card is as follows. It is required to satisfy various conditions. That is, in order to make the entire IC card thin, the printed wiring board for the IC card itself must be thin.

The IC card may be handled by hand or may be subjected to careless force, and if such force is applied, the printed wiring board for the IC card may be easily damaged or deformed. It shouldn't be.

As a matter of course, an IC card Punlint wiring board for constructing this kind of IC card must have high reliability.

The IC card is electrically connected to an external device by its contact terminal. However, the contact terminal should not be an obstacle to the IC card as a matter of course. Therefore, this contact terminal needs to be smooth with respect to the substrate of the IC card printed wiring board.

It must be able to be manufactured at low cost.

In order to meet the above conditions, various ICs have been
Printed wiring boards for cards have been proposed. For example, although a printed wiring board for an IC card as shown in FIG. 8 has been proposed, in this printed wiring board for an IC card, the electronic component (30) is placed in the hole formed in the substrate (41). A conductor layer (42) that stores and closes each hole.
Is formed. Then, as shown in FIG. 9 or 10, a part of the conductor layer (42) is exposed to the outside of the IC card to form a contact terminal which serves as an external contact. Printed wiring board (40A) for IC card in this example
In that case, since a single-sided copper clad plate can be used and the electronic component (30) is housed in the hole formed in the substrate (41),
The whole can be made thin. However, when the electrical connection between the electronic component (30) and the conductor layer (42) is made by the bonding wire (31), it has to be made through each hole formed in the substrate (41), so that the substrate (41 There is a limit to the degree of processing of
A good bonding wire (31) is used and it tends to be inferior in reliability.

On the other hand, a printed wiring board (40B) for IC cards as shown in FIG. 11 has also been proposed. In this printed wiring board (40B) for an IC card, a through hole (43) is formed in a substrate (41), and an electronic component (30) and a conductor layer (42) are formed through this through hole (43). Are connected by a bonding wire (31) and housed in a card base material (20) as shown in FIG. 12 to form an IC card. In the printed wiring board (40B) for IC card shown in FIG. 11, the reliability of connection by the bonding wire (31) like the printed wiring board (40A) for IC card shown in FIG. No less inferior,
Stain and moisture easily enter from the outside through the through hole (43), which tends to result in poor reliability. Furthermore, since it is a double-sided printed wiring board, it is not suitable for cost reduction.

In view of the actual condition of this type of printed wiring board for an IC card, the inventors of the present invention have earnestly studied to develop one that can surely satisfy the conditions required for the above-mentioned type of printed wiring board. As a result, the inventors have newly discovered that it is possible to obtain good results by forming the contact terminal portion by plating by using the substrate of the single-sided printed wiring board as a substitute for the plating mask, and completed the present invention.

(Problems to be Solved by the Invention) The present invention has been made based on the above situation.
The problems to be solved are the lack of reliability in the conventional printed wiring boards for IC cards and the high cost with low industrial utility value.

And an object of the present invention is to provide a printed wiring board for an IC card which is highly reliable and can be manufactured at low cost by forming the contact terminals by plating instead of the base material as a mask. To provide.

(Means for Solving Problems) Means adopted by the present invention for solving the above problems are
Explaining with reference to FIG. 1 to FIG. 7 corresponding to the embodiment, “a plurality of contact terminals (15) whose surfaces are exposed to the outside of the IC card and serve as external contacts, and an electronic component (20) are mounted A printed wiring board for an IC card having a part (16), wherein the printed wiring board (10) comprises a base material (11) having a copper foil (13) attached to one surface thereof, A through hole (1) closed by the copper foil (13) is provided at a position corresponding to the contact terminal (15).
2), and the through-hole (12) has a plating layer () that has grown from the copper foil (13) along the wall surface of the through-hole (12) to substantially the same surface as the surface of the base material (11). 14), the surface of the plating (14) is exposed to the outside of the IC card together with the surface of the base material (11), and the contact terminal (15)
The printed wiring board for IC cards (1
0) ”.

That is, in this printed wiring board for an IC card (10), the basic structure is a base material (11) and a conductor layer (13) made of a copper foil attached to the back surface of the base material (11). , Substrate (1
It has a structure in which a copper foil, that is, a conductor layer (13) grown from the conductor layer (13) to approximately the same surface as the base material (11) along the wall surface of the through hole (12) formed in 1) is filled with plating (14). By using a single-sided copper clad board, the structure is simple
This is to make IC cards thinner.

This printed wiring board for an IC card (10) is configured as an IC card by being housed and fixed in a card base material (20) as shown in FIG. 1 or FIGS. 4 to 6. As shown in FIG. 1, a part thereof has a plurality of contact terminals (15) exposed to the outside of the IC card and serving as external contacts. In the printed wiring board (10) for an IC card according to the present invention, the surface of the plating (14) corresponds to the contact terminal (15) as it is. The IC card printed wiring board (10) has a sectional structure as shown in FIGS. 2 and 3.

The IC card printed wiring board (10) first has a base material (11) as a basic structural material thereof. By subjecting the base material (11) to various processes, a printed wiring board for an IC card is obtained. It is formed as a plate (10). That is,
A through hole (12) is formed in a portion of the base material (11) corresponding to each contact terminal (15), and a copper foil is attached to the back surface of the base material (11) to form a predetermined conductor layer. (13) to close the through hole (12). FIG. 7 shows an example of a state in which the through hole (12) is formed in the base material (11). Among the through holes (12) in this example, each contact terminal (15)
Holes for forming plating for protecting each contact terminal (15) are formed around the area corresponding to. By doing so, a space can be formed in the portion that will be the contact terminal (15), but this space, that is, the through hole (12) is filled with plating (14). In this case, by adjusting the amount of the plating (14) filling the through hole (12), the surface of the plating (14) (that is, this becomes the contact terminal (15) of the IC card printed wiring board (10). Is present on the same surface as the surface of the base material (11). The surface of each plating (14) formed as described above is polished, if necessary, to form a base material (11).
The surface may be positively processed so as to form the same surface.

After that, as shown in FIG. 1 and FIG. 3, the electronic component (30) is mounted on the portion to be the mounting portion (16) of the conductor layer (13), and the electronic component (30) and the conductor layer ( It is electrically connected to 13) by a bonding wire (31) to form a completed IC card printed wiring board (10).
This printed wiring board for an IC card (10) may be completely embedded in a card substrate (20) to form an IC card as shown in FIG. 4, and as shown in FIG. The IC card printed wiring board (10) may be supported by a laminate film attached to the surface of the card substrate (20). Furthermore, as shown in FIG. 6, the base material (11) itself is configured to have the same size as the card base material (20), and this is directly attached to the surface of the card base material (20) to form an IC. It may be implemented as a card.

(Operation of the Invention) The present invention adopts the above-mentioned means and has the following operation.

Printed wiring board for IC card (10) configured as above
In this case, since the copper foil is attached to the base material (11) to form the base body, the printed wiring board (10) for IC card itself is also thin.

Since the electronic component (30) is directly supported by the highly rigid base material (11) via the conductor layer (13), force is applied to the IC card when the IC card is carelessly handled by human hands. However, the IC card printed wiring board (10) is not easily damaged or deformed.

The through holes (12) of the base material (11) are completely filled with the plating (14) and there are no other gaps. Therefore, the IC card printed wiring board (10) ) Is highly reliable because dust and water do not enter the electronic component (30) side during its use.

Since each contact terminal (15) and the surface of the base material (11) form the same force surface, this contact terminal not only makes smooth electrical connection with an external device, but also interferes with the IC card. It is not supposed to become. Gonna
This contact terminal is a printed wiring board (1
It is smooth with respect to the substrate of 0).

Since the conductor layer (13) is attached to the base material (11) and then the plating (14) is formed in each through hole (12), this IC
The printed wiring board (10) for cards can be manufactured at low cost.

(Example) Next, the present invention will be described in detail according to an example.

Example 1 A glass epoxy resin substrate having a thickness of 0.13 mm (hereinafter, mm thickness is abbreviated as t) (manufactured by Risho Kogyo Co., Ltd., trade name ES-3524, with 0.025 t adhesive layer on one side) (this is the base material ( 11)), the through hole (12) is punched out by a mold, and 0.018 t of electrolytic copper foil (which becomes the conductor layer (13)) is bonded to the adhesive layer surface by a thermocompression bonding press to form an adhesive. Completely cure. Resist formation and etching for this electrolytic foil,
After removing the resist, use a sparger plating device (partial plating can be performed) to 100 A / d with copper sulfate plating solution.
Base material (11) by plating at m ² for about 6 minutes and 30 seconds
About 110μ from the thickness of the conductor layer (13) in the through hole (12)
It was possible to form a thick plating (14). afterwards,
After polishing the contact terminal side to the same height as the base material surface,
By applying electrolytic nickel plating 0.3 μm and electrolytic pure gold plating 0.3 μm, a printed wiring board (10) for an IC card as shown in FIG. 2 was obtained.

Example 2 After punching the through hole (12) and its surroundings using a 0.1t polyester base material (trade name Lumirror 100S manufactured by Toray) with a 0.025t adhesive layer on one side, see 0.018. After the electrolytic copper foil of t is bonded by a thermocompression bonding press to form a liquid resist coating in the through hole (12) and the hole punched around it,
Conductor circuits were formed in the same manner as in Example 1.

The base material (11) thus formed was further copper-plated only on the portion of the through hole (12) to be an external contact terminal by using the sparger plating apparatus similar to that of the first embodiment. The thickness of this plating was made smaller than the thickness of the base material, and then nickel plating and gold plating were performed, and finally the plating thickness was made approximately the same as that of the base material. Thereafter, the outer shape was processed in the same manner as in Example 1 to obtain an IC card printed wiring board (10) as shown in FIG. As shown in the structure of this embodiment, by projecting a copper foil at the end of the substrate, the IC shown in FIG.
The structure of the card is taken and the bending resistance of the IC card is improved.

Example 3 In the same manner as in Example 1, patterning, formation of contact terminals by plating, Ni-Au plating, IC chip mounting,
After sealing with a resin, the outer shape was processed into the same size as the card. By laminating this on a card resin, an IC card shown in FIG. 6 was obtained. This structure allows the IC card to have sufficient flex resistance without the need for a laminate film.

(Effects of the Invention) As described in detail above, according to the present invention, as illustrated in the above embodiment, "a plurality of contact terminals (15) whose surfaces are exposed to the outside of the IC card and serve as external contacts" are provided. A printed wiring board for an IC card having an electronic component (20) mounting portion (16), wherein the printed wiring board (10) comprises a base material (11) having a copper foil (13) attached to one surface thereof, A through hole (1) closed by the copper foil (13) is provided at a position of the base material (11) corresponding to the contact terminal (15).
2), and the through-hole (12) has a plating layer () that has grown from the copper foil (13) along the wall surface of the through-hole (12) to substantially the same surface as the surface of the base material (11). 14), the surface of the plating (14) is exposed to the outside of the IC card together with the surface of the base material (11), and the contact terminal (15)
Therefore, there is no unreliability of wire bonding of the conventional technology, and naturally, as a printed wiring board for IC cards equipped with flip-chip bonding and TAB, it has all the reliability. Thus, it is possible to provide a printed wiring board (10) for an IC card, which has high performance and can be manufactured at low cost.

That is, since the copper foil is adhered to only one side of the base material (11) as a base body, the IC card printed wiring board (10) itself can be made inexpensive and have a thin structure.

Since the electronic component (30) is directly supported by the highly rigid base material (11) via the conductor layer (13), force is applied to the IC card when the IC card is carelessly handled by human hands. However, the printed wiring board (10) for IC card is not easily damaged or deformed.

The through holes (12) of the base material (11) are completely filled with the plating (14) and there are no other gaps. Therefore, the IC card printed wiring board (10) ), Dust and water will not enter the electronic component (30) side during its use.
0) can be highly reliable even for long-term use.

Since each contact terminal (15) and the surface of the base material (11) are substantially flush with each other, this contact terminal not only facilitates electrical connection with an external device but also interferes with the IC card. It is not supposed to become. That is,
Since the contact terminals of this IC card printed wiring board (10) are smooth with respect to the substrate of the IC card printed wiring board (10), this IC card printed wiring board (10) is It is possible to make it easy to use the IC card using the.

Since the plating (14) may be formed in each through hole (12) after the conductor layer (13) is attached to the base material (11), a plating mask is not required, and the printed wiring board for the IC card is used. (10) can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view of an IC card incorporating a printed wiring board for an IC card according to the present invention, and FIG. 2 is an enlarged vertical sectional view of the printed wiring board for an IC card as seen along the line II-II in FIG. 3 and 4 are enlarged vertical sectional views corresponding to FIG. 2 showing another embodiment, and FIG. 4 is a first view showing a state in which a printed wiring board for an IC card according to the present invention is built in a card base material. FIG. 5 is a vertical sectional view of the IC card taken along line II-II in FIG. 5, FIG. 5 and FIG. 6 are sectional views corresponding to FIG. 4 showing another embodiment, and FIG. It is a partial enlarged plan view of a substrate showing a state. FIG. 8 is an enlarged vertical sectional view showing a conventional example of a printed wiring board for an IC card, and FIGS. 9 and 10 show the conventional printed wiring board for an IC card shown in FIG. 8 in a card base material. Fig. 11 is an enlarged vertical sectional view showing another example of a conventional printed wiring board for an IC card, and Fig. 12 is a conventional IC card print shown in Fig. 11. It is sectional drawing which shows the state which built the wiring board in the card base material. Explanation of symbols 10 …… Printed wiring board for IC card, 11 …… Base material, 12 ……
Through hole, 13 ... Conductor layer, 14 ... Plating, 15 ... Contact terminal, 16 ... Mounting part, 20 ... Card base material, 30 ... Electronic component, 31 ... Bonding wire.

Claims (1)

[Claims] 1. A printed wiring board for an IC card, which has a plurality of contact terminals whose surfaces are exposed to the outside of the IC card to serve as external contacts and an electronic component mounting portion, wherein the printed wiring board has a copper foil on one side. And a through hole closed by the copper foil at a position corresponding to the contact terminal of the base material. The through hole is a wall surface of the through hole from the copper foil. And a plating layer that has grown substantially flush with the surface of the base material, and the plating layer surface is exposed to the outside of the IC card together with the surface of the base material to form the contact terminal. Printed wiring board for IC card.