JPH0676000B2 - IC card manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an IC card used in an IC card system, and more particularly to an IC card for preventing unauthorized reading of stored information inside the IC card. Manufacturing method.

[Prior Art and Problems Thereof] In recent years, it is called a cashless era, and by using a card issued by a credit card company or the like, it is possible to purchase a product without handling cash.

Conventionally used cards include plastic cards, embossed cards, magnetic stripe cards and the like, but since these cards are structurally easy to forge, illegal use has become a problem.

Therefore, in order to solve such a problem, an information card, that is, an IC card, in which an IC circuit storing a personal identification number or the like is incorporated in the card so that the personal identification number cannot be easily read from the outside, is considered. An IC card system combining such an IC card and a terminal has been developed.

By the way, ICs used in such IC card systems
The card is manufactured through the process shown in FIG. 6 and delivered to the card holder.

In this case, card manufacturer 1, issuer 2, cardholder 3
Therefore, when manufacturing the IC card, the card manufacturer 1 first manufactures an IC circuit on the wafer in step A1, and in this state, the process proceeds to step A2 to execute a functional test on each pellet. In this case, the IC circuit is CPU and EEP-ROM
However, since the I / O terminal for inputting / outputting data usually has only one pin, it takes too much time to perform various inspections using this terminal, which is extremely inefficient. Target. Therefore, in order to improve the efficiency of this function test, the data pads and address pads are brought out to the outside from the data line and address line between the CPU and EEP-ROM, respectively. I try to do various inspections.
When the functional inspection of each pellet is completed in this way, dicing is then performed in step A3, and then the process proceeds to step A4 where bonding is performed.
In this step A4, die bonding for adhering the IC pellet to the base and wire bonding for connecting the lead to the actually used terminal of the IC pellet are performed.
This state is shown in FIG. In this figure, 4 is
The IC pellets 5 are formed with a substrate having an opening 5a for accommodating the IC pellets 4, and 6 is formed with a bonding portion projecting on the opening 5a of the substrate 5 and an external terminal portion when incorporated in an IC card. It is a lead. Based on the proposal of the ISO standard, the leads 6 are formed by 8 pieces of 4 columns and 2 rows, and are individually diced.
The IC pellet 4 is die-bonded onto a base not shown, the opening 5a of the substrate 5 is fitted onto the IC pellet 4, and the bonding portion of each lead 6 and the terminal of the IC pellet 4 are aligned and bonded. . Here, 7 and 8 are the data pad and the address pad for the above-described function inspection.

Next, in step A5, resin sealing (not shown in FIG. 7) is performed on the main surface including the bonded portion of the IC pellet 4, and step A6
Proceed to. In this step A6, ICs that have completed resin encapsulation
A final inspection of the pellet is performed. This inspection is the 7th
The data pad and address pad 7 shown in the figure,
If 8 is resin-sealed, the probe is connected to the external terminal of the lead 6. In this case, in step A4,
If the SD lead is extended from the functional inspection pad, the inspection can be performed via the inspection pads 7 and 8 even after being covered with the sealing resin. Then, the IC pellet 4 joined to the substrate 5 by the lead 6 is peeled off from the die-bonding base, and is assembled in the card body in step A7.
IC card manufacturing is completed.

Next, in step A8, the card manufacturer writes a predetermined code in the card using the card terminal. That is, in this case, codes such as "CA", "IPIN", "PMK", "PRK" are written. Here, "CA" is the code used to encrypt and decrypt the message. "IPIN"
Is a random 6-bit code, PIN code
Used until is used. “PMK” is the serial number ”
The same number is used for each group. "PRK" is a code for decryption.

In this way, when the predetermined code is written on the IC card, "PMK" is printed and output. With this, the card manufacturer 2 sends the card on which the predetermined code is written and the printing paper of "PMK" to the issuer 2 by a separate flight. Issuer 2 inputs the account number "PAN" for the IC card using the IC card issuing terminal in step A9. in this case,
"PAN" is written in the IC card only when "PMK" written in the IC card and "PMK" entered from the terminal match. At the same time, the "IP
"IN" is printed out. The issuer 2 sends the IC card in which "PAN" is written and the printing sheet of "IPIN" to the cardholder 3 by separate flight. When the IC card and the printing paper are sent, the cardholder 3 goes to the issuer 2 in step A10, and inputs his / her personal identification number "PIN" using the terminal of the cardholder installed there. . In this case, "PIN" is the "IIN" written in advance on the IC card.
It is written on the IC card only when the "PIN" and the "IPIN" entered from the terminal match. Through the above process, the issuing process of the IC card is completed, and this card can be actually used.

By the way, in the IC card manufactured and issued in this way, the steps performed for the IC circuit housed inside
The data pad and address pad used in the final inspection of A6 are directly connected to the IC circuit and incorporated.

For this reason, when this IC card gets into the stage of actual use and is stolen or misplaced, it can be used as it is by the data pad and address pad if the inside of the card is opened illegally. Only by applying a probe to these pads, secret data such as PIN can be easily read from EEP-ROM or the like. This makes it possible to counterfeit the card based on these data, not only significantly reducing the reliability of the IC card, but in the worst case, the technical contents of the entire system are analyzed and extensively abused. There was a risk that

[Object of the Invention] The present invention has been made to eliminate the above-mentioned drawbacks.
An object of the present invention is to provide an IC card manufacturing method capable of reliably preventing illegal reading of stored information stored in the card.

[Points of the Invention] A method of manufacturing an IC card according to the present invention is to manufacture an IC pellet on which an inspection pad is formed, perform a functional inspection of the manufactured IC pellet using the inspection pad, and end the functional inspection. After that, the inspection pad is removed, and the IC pellet from which the inspection pad has been removed is incorporated into the card body.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a process until the IC card of the present invention is manufactured.

In the figure, first, in step B1, an IC circuit is manufactured on the wafer. Then, in this state, proceed to step B2,
A functional test is performed on each IC pellet. In this case, the IC circuit on the wafer is the CPU and EEP-ROM as described above.
Since the data pad and the address pad are exposed to the outside from the data line and the address line, respectively, various inspections are performed by applying a probe to these pads. After that, when the functional inspection for each of the pellets is completed, the process proceeds to step B3, and dicing is performed. And this step B3
After dicing in, proceed to step B4. This step B4
Then, the data and address test pads provided on the IC pellet obtained by dicing are removed. In this case, as shown in FIG. 2 (A), for example, the inspection pads are removed by dicing the data and address inspection pads 12 and 13 exposed on both side edges of the IC pellet 11 from the broken line shown in the drawing. To remove. Alternatively,
As a means for removing these inspection pads, a laser beam is used to remove the inspection pads 12 and 13 and the wiring pattern connected to these pads. Alternatively, the test pads 12 and 13 are corroded and removed using an etching solution. In FIG. 2, 14 are various terminals actually used for the IC pellet.

Then, it proceeds to step B5. In step B5, bonding is performed. In this bonding, die bonding to bond the IC pellet to the base (not shown) and
Wire bonding is performed to connect the leads to the actually used terminals of the IC pellet. That is, as shown in FIG. 2B, a lead 16 having a joint 16a protruding above the opening 15a provided in the substrate 15 and a connecting terminal connected to a contact portion of an IC card to be described later is not shown in the drawing. Each terminal 14 of IC pellet 11 die-bonded on the table
Positioned on the top, each lead 16, the joint 16a, and the terminal 14 are joined by thermocompression bonding or pulse heating.

Next, after performing resin sealing in step B6, the process proceeds to step B7, where test data is written in the test area of the memory section of the IC pellet. The data in this case is the minimum data necessary for the basic operation of the IC card, and is input using the I / O pins actually used.

In this state, the process proceeds to step B8. In this step B8,
The final inspection of the IC pellets completed with resin sealing is performed. This test uses the I / O terminals described above to perform a basic test for PINs and the like. Then, the IC pellets are separated from the base and mounted in the card body in step B9. In this case, the IC pellet 11 is attached to the substrate 15 as shown in FIG. This substrate 15 is an IC pellet
The connection terminal portion of the lead 16 electrically connected to 11 is connected to the contact 17a provided so as to be exposed from the inner surface to the outer surface of the top film 17. The IC pellet 11 and the substrate 15 are housed in the opening 18a of the inner sheet 18, and the lower surface film 19 is superposed on the lower surface of the inner sheet 18 to be integrated with each other, thereby completing the IC card. The upper film 17 and the lower film 19 can be made of soft PVC, and the inner sheet 18 can be made of hard PVC or the like. Thus obtained
The IC card 20 is shown in FIG. In FIG. 4, 20a is a magnetic stripe, which is formed on the upper surface film 17 after the IC pellet is incorporated.

After that, such an IC card is subjected to the issuing process and can be actually used. However, since this issuing process is the same as steps A8 to A10 in FIG. 6 described above, the description thereof is omitted here.

Therefore, in this way, the IC chip built into the IC card is designed to remove the data and address pads used for these tests after the first functional test, so that it can be used in the subsequent stages. Even if a third party illegally obtains this card and tries to read the data by opening the inside of the card, it does not give any clue, and ensures the illegal reading of the data stored in the storage unit. Can be prevented.

The present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented within the scope of the invention. For example, in the above-described embodiment, the bonding is performed in step B5, but the external terminal may be formed without performing such bonding. That is, in this case, the IC pellet is constructed as shown in FIG. In the figure, 21 is a silicon substrate, and an active region 22 is formed on this substrate 21. Then, an insulating film is formed on this region 22.
An internal connection pad 24 is formed, a part of which is electrically connected to the region 22 via 23. Further, an insulating film 25 is formed on the pad 24, and an external connection pad 26 having a large area, a part of which is electrically connected to the internal connection pad 24, is formed on the insulating film 25. Then, such an IC pellet is adhered to a substrate or the like by using a well-known anisotropic conductive adhesive, and this is incorporated into a card body to complete an IC card. The anisotropic conductive adhesive is Ni, A in hot melt type insulating adhesive.
It contains conductive particles such as g and carbon, and exhibits conductivity only in the direction compressed by thermocompression bonding, but if the connecting terminals are extremely fine, conductive particles are placed on the terminals. It may not be done. However, by increasing the area in this way, it is possible to surely eliminate this problem and obtain a joint structure with high reliability of conduction. Moreover, since this method does not require accurate alignment such as bonding, the IC pellet and the substrate can be bonded efficiently.

[Effects of the Invention] According to the present invention, it is possible to surely prevent illegal reading of stored information stored in the card, so that it is possible to prevent forgery of the card by a third party and improve the reliability of the IC card. Moreover, it is possible to prevent the technical contents of the entire system from being misused.

[Brief description of drawings]

FIG. 1 is a flow chart showing a process until an IC card of an embodiment of the present invention is manufactured, and FIG. 2A is a perspective view for explaining a chip incorporated in the IC card of the embodiment. 2 (B) is a perspective view showing a state in which the IC pellet inspection pad is cut off and then joined to the substrate, FIG. 3 is a longitudinal sectional view showing the IC card of the same embodiment, and FIG. FIG. 5 is an external perspective view of the obtained IC card, FIG. 5 is a longitudinal sectional view showing an IC card of another embodiment of the present invention, and FIG. 6 is a flow chart showing a process until a conventional IC card is manufactured.
The figure is a perspective view showing a bonded state of an IC pellet and a substrate incorporated in the same IC card. 4 ... IC pellet, 5 ... Substrate, 6 ... Lead, 7, 8
...... Data address pad, 11 …… IC pellet, 1
2, 13 …… Data and address pads, 14 …… Terminals, 15 …… Board, 17 …… Top film, 17a …… Contacts, 18 …… Inner sheet, 19 …… Bottom film, 20 ……
IC card, 21 ... Silicon base, 23, 25 ... Insulating film, 2
4, 26 ... Connection pad.

Claims (4)

[Claims] 1. An IC pellet on which an inspection pad is formed is manufactured, the manufactured IC pellet is functionally tested using the inspection pad, and the inspection pad is removed after the functional inspection is completed. A method for manufacturing an IC card, characterized in that the IC pellets from which the pads for use are removed are incorporated into the card body. 2. The method of manufacturing an IC card according to claim 1, wherein the inspection pad is removed by dicing a portion of the IC pellet on which the inspection pad is arranged. 3. The method for manufacturing an IC card according to claim 1, wherein the inspection pad is removed by a laser beam. 4. The method of manufacturing an IC card according to claim 1, wherein the inspection pad is removed by corroding the pad portion with an etching solution.