JPS61254398A - IC card - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an IC card including a semiconductor integrated circuit, and particularly to an electrical connection method suitable for preventing electrostatic damage of a semiconductor integrated circuit.

[Background of the invention]

Conventional IC cards are provided with a slidable cover to protect the contact terminals from the external environment, as described in Japanese Utility Model Application Publication No. 70262/1983.

Although this method was effective against soiled contacts and mechanical damage, it was not effective against electrostatic damage to semiconductor integrated circuits, which would result in permanent damage.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrical connection method with an external device that eliminates the above-mentioned drawbacks and can prevent electrostatic damage to semiconductor integrated circuits contained in an IC card.

[Summary of the invention]

Destruction of semiconductor integrated circuits due to static electricity occurs when the connection terminals connected to the top are open, and each terminal has a different potential due to the introduction of static electricity, and the potential difference between the terminals causes a breakdown such as junction breakdown strength or gate breakdown strength. Permanent destruction occurs when the Therefore, in order to prevent this destruction, all connection terminals may be held at the same potential except when connected to an external device.

Moreover, as another means, an effect can be obtained by connecting a capacitor to the power supply terminal of the semiconductor integrated circuit.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is an external view of the IC card 1 described in this embodiment, in which a semiconductor integrated circuit is embedded and electrical connection ends 7 (78 to 7c) for connection with external devices are provided.

Next, the configuration and operation of this embodiment will be explained with reference to FIGS. 2 to 4. FIG. 2 shows a cross-sectional structure taken along line XX' in FIG. In FIG. 2, the semiconductor integrated circuit 2 is
It is housed in a recess provided on the IC card board 3 and connected to a connection terminal 5 with an external device via wiring 4, and the semiconductor integrated circuit 2 and wiring 4 are covered with a protective film 6. More protection! ! The membrane 6, the connection terminals 5, and the substrate 3 are covered with an IC card top cover 8, leaving only the contact point 7 with the external device, and a shorting metal 9 for shorting between the terminals according to the present invention. establish. Note that the connection terminal 5 with the external terminal is made of elastic metal, and a cavity is provided below the contact point 7 with the external terminal.

FIG. 3 shows a cross-sectional view taken along lines AA' and BB' in FIG. In this embodiment, three terminals 7a to 7c are short-circuited at the same time.

FIG. 4 is an enlarged view of the vicinity of contact point 7 in FIG.
FIG. 4(a) shows a state in which the contact needle 10 of the external device is not in contact, and 78 to 7c shown in the BB' cross section of FIG. 3(b).
The respective terminals are all at the same potential due to the shorting metal 9.

FIG. 4(b) shows that when the contact needle 10 of the external device contacts the contact point 7 and pushes down the contact point 7, the external connection terminal 5 and the shorting metal 9 are separated, and the semiconductor integrated circuit included in the IC card is removed. An electrical connection is made between the circuit and an external device.

According to this embodiment, when there is no contact with an external device, all terminals of the semiconductor integrated circuit are always kept at the same potential, making it possible to prevent destruction of the semiconductor integrated circuit due to static electricity.

FIG. 5 maintains the effects described in the above embodiment, and
This is a second embodiment in which by opening the lower surface of the contact point 7, the contact points with the external device can be obtained at both sides of the contact point 7 and 7'. The second embodiment has the effect that cleaning of the contacts is facilitated by leaving both sides of the electrical contacts open.

Next, another embodiment of the present invention will be described with reference to FIGS. 6 to 8.

FIG. 6 is an external view of the IC card 100 described in this embodiment. The card 100 has a built-in semiconductor integrated circuit, and a circuit board for electrically connecting the semiconductor integrated circuit to an external data transmitting device. Connection terminal 11 (lla~11e
)have.

FIG. 7 is a cross-sectional structure of the IC card shown in FIG. 6 taken along line xx'. In FIG. 7, a semiconductor integrated circuit 12 is housed in a recess 14 of a card board 13, and is connected to an electrical contact 11 with an external device via wirings 15' and 16. The semiconductor integrated circuit 12 and wiring 16 described above are covered with a protective film 17 to provide mechanical strength and moisture resistance.

Next, the configuration according to the present invention will be explained with reference to FIGS. 7 and 8. Figure 8 shows the structure of each layer of the IC card.
(D) is a metal layer 15 that becomes one electrode of the capacitor, and in this embodiment, it is the same layer as the wiring 15' that electrically couples the semiconductor integrated circuit 12 and the external data transmitting device shown in FIG. It consists of A metal layer 19 that will become the other electrode of the capacitor is further laminated on top of the metal layer 15 with a dielectric film 18 interposed therebetween. By connecting the metal layers 15 and 19 to separate power supply terminals, a circuit configuration as shown in FIG. 9 is obtained, and the capacitor 22 described above can be wired between the power supply terminals 11a and 11b. can. The capacitance at this time is determined as follows. 8th
The area of the metal layer 15 that becomes the electrode of the capacitor in FIG. 8(D) is S, the thickness of the dielectric film 18 in FIG. 8(C) is Q, and the I of 18 is
! When the rate is ε, the capacitance C becomes C=i·−[F].

An IC card is constructed by covering the capacitor described above with a protective film 20 provided with a window 21 (21a to 21e) for opening only the upper part of the connection terminal 11 shown in FIG. This embodiment described above has the following effects. The first effect is that by coupling a capacitor to the power supply terminal, while power is being supplied to the power supply terminal, noise that enters the power supply terminal can be absorbed and a stable voltage can be supplied to the semiconductor integrated circuit. The second effect occurs when the power supply terminal is open.

It is possible to strengthen the strength of the semiconductor integrated circuit to break down due to static electricity that enters from the power supply terminal. The third effect is that the upper part of the semiconductor integrated circuit can be covered with a metal layer, which prevents moisture from entering.6 Furthermore, by giving the metal layer mechanical strength, the mechanical strength of the IC card Damage can be prevented.

The third effect is that EEFROM (EEFROM), which has an internal booster circuit and can be electrically erased and written, is a semiconductor integrated circuit.
Electrically Erasabla an
d ProgrammableRead 0nly
(Men+ory), it can be used as a backup capacitor to prevent erroneous erasing and erroneous writing during power outages.The above six embodiments and effects have been described using the example of connecting a capacitor to the power supply terminal. It is also possible to use the capacitor coupled to other terminals (for example, input/output terminals).

〔Effect of the invention〕

According to the first means of the present invention, the connection terminals of the semiconductor integrated circuit included in the IC card with external devices are all at the same potential when not in use, and high voltage due to static electricity or the like is applied to the connection terminals. Even in such cases, it has the effect of preventing damage to the semiconductor integrated circuit.

According to the second means of the present invention, it is possible to obtain an IC card in which a capacitor is connected to the power supply terminal, which has the effect of stabilizing the voltage during power supply and improving the electrostatic breakdown strength when the power supply terminal is opened.

[Brief explanation of drawings]

FIG. 1 is an external view of an IC card according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line xx' in FIG. 1, and FIG.
4 is an enlarged view of the vicinity of 7 in FIG. 2, and FIG. 5 is a sectional view taken along line xx' in FIG. 1, explaining the second embodiment. , FIG. 6 shows I of another embodiment of the present invention.
FIG. 7 is a cross-sectional view taken along line xx' in FIG. 6, FIG. 8 is a diagram showing the structure of each layer of the IC card, and FIG. 9 is a circuit diagram of an embodiment of the present invention. 3.13...IC card board, 2.12...semiconductor integrated circuit, 4.5...connection wiring, 7,11...contact terminal. 8...Protective cover, 9...Short circuit metal, 10...
Contact needle of external device, 15.19... Electrode plate, 18...
・Dielectric material/−ゝ、゛. Figure 41 A Figure 2 Figure 3 Not ,! Figure 5 Figure 5 Figure vine 7 Figure■3 Figure Zρ

Claims (1)

[Claims] 1. In a card including an IC and having a plurality of connection terminals for electrically connecting the IC and an external data transmission device, there is a conductive device in the card that short-circuits the connection terminals. I characterized by being provided with a magnetic material or a capacitor.
C card. 2. In the IC card according to claim 1,
An IC card characterized in that a terminal that contacts an external device and serves as an electrical contact has a hollow or open area around the surface opposite to the contact.