HK1092567B - Ic card and method for producing the same - Google Patents

Description

IC card and method for manufacturing the same

Technical Field

The present invention relates to an IC card provided with an unnecessary radiation countermeasure necessary for ensuring a required function, product quality, and the like, and a manufacturing method thereof.

Background

In the field of household appliances and computing mobile products, high functionalization is required in the trend toward lighter, thinner and more compact. There is also a trend toward higher functionality in the card industry. For credit and cash cards used heretofore, the primary stream of recorded data was embossments and magnetic strips. However, recent attention has been paid to high functionalization such as a multi-function solution for credit cards, electronic money, and the like by IC cards.

To cope with such a trend, IC chips have been required to have a large capacity and a high density. Among them, a great deal of research and development has been made on encryption techniques and high-speed signal processing techniques for important information. In addition, not only can a large amount of information be read from or written to the card, but various applications have been proposed to actively utilize the information in the card and to produce various types of use. As the use type is changed in various ways, the current situation of the product quality of IC cards requires satisfying the product quality in various environments/occasions in addition to the high security and high-speed processing performance performed so far (for example, japanese patent application laid-open nos. HEI-6-336095 and HEI-9-27839 and japanese patent application laid-open No. 2001-53487).

As the use type is changed in various ways, the quality requirement for the IC card is increased in addition to high security and high-speed processing performance. Among them, the quality of the usage type applicable to mobile communication terminals, typically IC cards and mobile phones, is urgently required to be able to satisfy the demand, because the number of users is expected to grow rapidly.

Services based on the type of use, such as confirming the recorded contents of an IC card (for example, card balance) using a display function of a mobile terminal having an embedded IC card reader/writer, have been rapidly developed. If communication of the mobile phone and communication between the IC card and the reader/writer occur simultaneously, such as incoming call during read operation of card information and communication between the IC card and the reader/writer during telephone service, two communication waves are picked up in the IC card, and they may be synthesized as a mixed modulation wave in the IC card. The mixed modulated wave may appear as noise to a received wave of the mobile phone, resulting in an incoming call failure, a telephone service failure, and the like.

If the mixed modulated wave is picked up near the transmission frequency of the mobile phone (e.g., 900 to 940MHz), the resultant waveform is as shown in fig. 3A. In some cases, smaller waveforms are generated on the left and right sides of fig. 3A. The waveform on the left side of fig. 3A is particularly likely to affect the reception frequency (843 to 885MHz) of the mobile phone, and becomes noise. In this case, the important communication function of the mobile phone cannot be maintained, and there is a fear that the voice function of the mobile phone and the IC card read/write function are limited to some extent.

The present invention has been made in view of the above-mentioned problems, and provides an IC card capable of suppressing radio waves generated during communication between mobile phones and communication between an IC and a reader/writer from being input to an IC chip, suppressing radio waves mixedly modulated in the IC chip from being output, and eliminating adverse effects on peripheral devices such as mobile phones, and a manufacturing method thereof.

Disclosure of Invention

In order to solve the above-mentioned problems, an IC card of the present invention is formed by sandwiching a circuit board on which an antenna pattern is formed and an IC chip mounted on the circuit board using a plurality of card constituting sheets, characterized in that: the circuit board is provided with a noise absorber for absorbing and canceling noise input to and output from the IC chip.

The method of manufacturing an IC card of the present invention includes: the method includes a step of mounting an IC chip on a circuit board on which an antenna pattern is formed, a step of sandwiching the circuit board on which the IC chip is mounted with a plurality of card-constituting sheets, and a step of providing a noise absorber for absorbing and eliminating noise input to and output from the IC chip on the circuit board.

By providing the circuit board with a noise absorber for absorbing and canceling noise input to and output from the IC chip, incoming noise is reduced, and output noise due to a mixed modulated wave synthesized in the IC chip is reduced. Adverse effects on the operation of the peripheral communication device and the like can be excluded.

The noise absorber is preferably mounted in a wiring area on a circuit board interconnecting the antenna wiring and the IC chip. Noise entering the IC chip through the antenna line can be reduced, and noise output to the antenna line can also be reduced.

The noise absorber may be a chip-type ferrite bead mounted on the circuit board and partially constituting the wiring, a magnetic layer formed on the circuit board partially covering the wiring area, or a magnetic material mixed and stirred with a sealing resin sealing the IC chip on the circuit board.

Drawings

Fig. 1 is a cross-sectional view of an IC card C1 according to a first embodiment of the present invention;

fig. 2 is a plan view of the circuit board 10 constituting the IC card C1;

FIGS. 3A and 3B are spectral analysis diagrams illustrating the operation of the present invention;

fig. 4 is a plan view showing the structure of the circuit board 10;

fig. 5 is an exploded perspective view of the IC card C1;

fig. 6 is a cross-sectional view of an IC card C2 according to a second embodiment of the present invention;

fig. 7 is a plan view of the circuit board 20 constituting the IC card C2;

fig. 8 is a cross-sectional view of an IC card C3 according to a third embodiment of the present invention;

fig. 9 is a plan view of the circuit board 30 constituting the IC card C3;

fig. 10 is a plan view showing the structure of the circuit board 30;

fig. 11 is a cross-sectional view of an IC card C4 according to a fourth embodiment of the present invention;

fig. 12 is a plan view of the circuit board 40 constituting the IC card C4;

fig. 13 is a plan view showing the structure of the circuit board 40;

fig. 14 is a cross-sectional view of an IC card C5 according to a fifth embodiment of the present invention;

fig. 15 is a plan view of the circuit board 50 constituting the IC card C5;

fig. 16 is a cross-sectional view of an IC card C6 according to a sixth embodiment of the present invention;

fig. 17 is a plan view of the circuit board 60 constituting the IC card C6;

fig. 18 is a plan view showing the structure of the circuit board 60;

fig. 19 is a side view showing the structure of sintered magnetic materials 61A and 61B mounted on the circuit board 60;

fig. 20 is a cross-sectional view of an IC card C7 according to a seventh embodiment of the present invention;

fig. 21 is a plan view of the circuit board 70 constituting the IC card C7.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[ first embodiment ] A method for manufacturing a semiconductor device

Fig. 1 and 2 illustrate a first embodiment of the present invention. Fig. 1 is a cross-sectional view of an IC card C1 of the first embodiment, and fig. 2 is a plan view of a circuit board 10 embedded in an IC card C1.

The IC card C1 is constructed in such a manner that: the circuit board 10 is embedded in the card base 3, the antenna pattern 1A and the IC chip 2 are formed on the circuit board 10, and the card base 3 is formed of a plurality of card constituent sheets that are thermally pressed and bonded.

As shown in fig. 2, the circuit board 10 is constructed in such a manner that: the conductive patterns 1 and 5 are formed on the front and back surfaces of an insulating resin film made of polyethylene naphthalate (PEN), polyethylene terephthalate (PET), Polyimide (PI), and the like. For example, the conductive patterns 1 and 5 are constructed such that a metal foil of copper or aluminum formed on the resin film is patterned in a predetermined shape.

The conductive pattern 1 formed on the front surface of the circuit board 10 is composed of a spiral antenna pattern 1A as an antenna line and an electrode pattern 1B constituting one electrode of the tuning capacitor 4. The conductive pattern 5 formed on the back surface of the circuit board 10 is constituted by a bridge pattern 5A for interconnecting the outer peripheral side of the antenna pattern 1A to the inner peripheral side and an electrode pattern 5B constituting the other electrode of the tuning capacitor 4.

The inner peripheral side of the antenna pattern 1A and the electrode pattern 1B are connected to one terminal of the IC chip 2, and the outer peripheral side of the antenna pattern 1A is connected to the bridge pattern 5A via the interlayer interconnection 6 a. The bridge pattern 5A and the electrode pattern 5B are connected to the other terminal of the IC chip 2 via an interlayer interconnect 6B.

The IC chip 2 is sealed with a sealing resin 7A, and a metal reinforcing plate 8A is bonded to the sealing layer to improve the strength of the IC chip. The reinforcing plate 8B is also formed on the chip non-mounting surface (back surface) side of the circuit board 10, in which the sealing resin 7B is involved, so as to sandwich the IC chip 2.

The card base 3 is constructed in such a manner as shown in fig. 5 to heat press and bond a pair of core pieces 3a and a pair of core pieces 3b and 3b, which sandwich the circuit board 10, respectively. The inner core sheet 3a and the outer core sheet 3b are made of a thermoplastic resin, such as a copolymer of terephthalic acid, cyclohexylamine, and ethylene glycol (PETG), and a composite (alloy) of the copolymer and Polycarbonate (PC).

As shown in fig. 2, through-holes 9 are formed through the circuit board 10 at a plurality of positions of an inner layer thereof to improve the bending-torsion strength of the circuit board 10.

Next, chip-type ferrite (ferrite) beads 11a and 11b are disposed on the circuit board 10. These ferrite beads 11a and 11b correspond to "noise absorbers" of the present invention for absorbing and canceling noise input to and output from the IC chip 2.

The ferrite beads 11A and 11b are mounted on the wiring portions 12a and 12b on the circuit board 10 interconnecting the antenna pattern 1A and the IC chip 2 by using solder 13. The ferrite beads 11a and 11b have a conductive layer partially constituting the wiring portions 12a and 12b and a magnetic layer absorbing and canceling noise (unnecessary radiation energy) input to and output from the IC chip 2.

A plurality of noises having different frequency bands are input to the IC chip 2, and a mixed modulation wave of these noises is output from the IC chip 2. In this embodiment, the ferrite beads 11a and 11b are selected to be able to absorb and eliminate noise of frequency components that can adversely affect the communication operation of a peripheral device (e.g., a mobile phone). The ferrite beads providing such characteristics may be "BLM 18BB470SN 1" ferrite beads manufactured by Murata Manufacturing co.

In the IC card C1 of the present embodiment constructed as above, a communication radio wave (for example, a communication frequency of 13.56MHz) oscillated from a reader/writer, not shown, causes the antenna pattern to generate an induced electromotive force, which is supplied as a drive voltage for the IC chip 2 to read (or write) information. In some cases, voice communication of the mobile phone is performed simultaneously.

Noise generated due to driving of the reader/writer and noise generated due to voice communication of the mobile phone are absorbed and eliminated by the chip-type ferrite beads 11a and 11b mounted on the line parts 12a and 12 b. Therefore, it is possible to effectively reduce noise input to and output from the IC chip 2 to prevent external radiation of noise and eliminate adverse effects on the operation of the peripheral communication apparatus.

Fig. 3A is a spectral analysis diagram when a waveform of voice communication of the mobile phone and a waveform of communication of the reader/writer in a communication frequency of 940MHz are synthesized in an IC chip of the IC card to be a hybrid modulation waveform output from the IC card after. As can be seen from fig. 3A, sideband waves appear at a fixed pitch (13.56MHz) on the high-frequency side and the low-frequency side near the peak of 940 MHz. There is a concern that these sideband waves adversely affect the communication operation of the mobile phone.

According to this embodiment, as shown in fig. 3B, noise radiation from the IC chip 2 of the IC card C1 can be effectively suppressed, so that the communication characteristics of the mobile phone can be stabilized. For example, if the mobile phone has an IC card reader/writer embedded in the terminal body, it is possible to prevent the communication operation with the IC card C1 from adversely affecting the communication operation of the mobile phone. Electromagnetic interference with an electronic apparatus placed near the IC card C1 can be avoided.

Next, a method of manufacturing the IC card of this embodiment constructed as above will be explained.

First, as shown in fig. 4, a process of mounting the IC chip 2 on the circuit board 10 is performed, and the conductive patterns 1 and 5 including the antenna pattern 1A are formed on the circuit board 10. This process of mounting the IC chip 2 performs a process of mounting the IC chip 2 on the circuit board 10, a process of sealing with the sealing resins 7A and 7B, and a process of bonding the reinforcing plates 8A and 8B.

Next, a process of mounting the ferrite beads 11a and 11b on the circuit board 10 is performed as shown in fig. 4.

In this embodiment, terminals of the ferrite beads 11a and 11b are bonded to pads 14 and 14 (fig. 4) of the line portions 12a and 12b constituting the conductive pattern 1 by using a bonding material 13 (fig. 2) such as solder. The mounting positions of the ferrite beads 11a and 11b are preferably positions close to the IC chip 2. The pad 14 is patterned when the conductive pattern 1 is formed or the continuously formed line portions 12a and 12b are cut by irradiating laser, for example.

Next, a process of forming a card by stacking the circuit board 10 mounted with the ferrite beads 11a and 11b and a plurality of card constituting sheets is performed.

In this embodiment, as shown in fig. 5, a pair of core sheets 3a and a pair of core sheets 3b and 3b are sequentially arranged and laminated on the circuit board 10, and these sheets are thermally pressed and bonded under a predetermined thermal pressing condition to form a card. Relief holes 3c and 3c for accommodating IC mounting ports are formed in the core pieces 3a and 3a, so that generation of irregular card surfaces can be suppressed.

According to this embodiment, the IC card C1 provided with unnecessary radiation countermeasures of the present embodiment can be easily manufactured by providing a process of mounting the ferrite beads 11a and 11b on the circuit board 10.

[ second embodiment ]

Fig. 6 and 7 illustrate a second embodiment of the present invention. Fig. 6 is a cross-sectional view of the IC card C2 of the embodiment, and fig. 7 is a plan view of the circuit board 20 constituting the IC card C2. In fig. 6 and 7, elements corresponding to those in the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, a noise absorber for absorbing and canceling noise input to or output from the IC chip 2 is constituted by a pair of magnetic layers 21A and 21B, the magnetic layers 21A and 21B covering the electrode patterns 1B and 5B and the wiring portions 12a and 12B constituting the tuning capacitor 4. For example, the magnetic layers 21A and 21B are constructed as radio wave absorbers made of an insulating material such as a synthetic resin filled with soft magnetic powder. The magnetic layer 21A is formed on the front surface side of the circuit board 20, and the magnetic layer 21B is formed on the back surface side of the circuit board 20.

The soft magnetic powder may be a landust alloy (Fe-Al-Si system), a Permalloy (Fe-Ni system), an amorphous (Fe-Si-Al-B system), a ferrite (Ni-Zn ferrite, Mn-Zn ferrite, etc.), a sintered ferrite, or the like. The magnetic layers 21A and 21B having the above-described structure may be magnetic sheets processed or formed into a sheet shape, or curable magnetic paste, magnetic compound, or the like coated in a layer shape.

The magnetic layers 21A and 21B perform an operation of absorbing and canceling noise input to or output from the IC chip 2 of the IC card C2. In this embodiment, almost all the wiring regions except the antenna pattern 1A are covered with the magnetic layers 21A and 21B to improve the noise absorption efficiency. The regions where the magnetic layers 21A and 21B are formed are not limited to this, but it is sufficient if these magnetic layers are formed at least in the regions where the antenna pattern 1A and the line portions 12a and 12B of the IC chip 2 are interconnected.

In manufacturing the IC card C2 constructed as above, after the IC chip 2 is mounted on the circuit board 20, the magnetic layers 21A and 21B are provided on the front and back surfaces of the circuit board 20. Similar to the first embodiment described above, the circuit board 20 is sandwiched by a plurality of card constituent sheets composed of a pair of inner core sheets and a pair of outer core sheets and formed into a card by hot pressing.

Relief holes are formed on the inner core sheets on the inner side to accommodate the magnetic layers 21A and 21B, so that the number of irregularities on the card surface is reduced after stacking the sheets, and the thickness of the card can be made thin.

If the magnetic layers 21A and 21B are made of a magnetic paste, the magnetic paste is subjected to a curing process after being applied, for example, together with the sealing resins 7A and 7B that seal the IC chip 2. If the magnetic layers 21A and 21B are made of a magnetic compound, after the magnetic compound is applied, the magnetic compound is subjected to a curing process while hot pressing for forming a card is performed.

According to the IC card C2 of this embodiment, similarly to the first embodiment, it is possible to eliminate noise from the IC chip 2 generated during card communication to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C2 can also be excluded.

According to this embodiment, compared with the first embodiment, welding or the like is not required. The manufacturing cost is reduced, the card can be more efficiently manufactured, and thus the product quality is stabilized.

[ third embodiment ]

Fig. 8-10 illustrate a third embodiment of the present invention. Fig. 8 is a cross-sectional view of the IC card C3 of the embodiment, fig. 9 is a plan view of the circuit board 30 constituting the IC card C3, and fig. 10 is a plan view showing the structure of the circuit board 30. In fig. 8 to 10, elements corresponding to those of the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, a noise absorber for absorbing and canceling noise input to or output from the IC chip 2 is constituted by a pair of magnetic layers 31A and 31B, the magnetic layers 31A and 31B covering the electrode patterns 1B and 5B and the line portions 12a and 12B constituting the tuning capacitor 4. Similar to the magnetic layers 21A and 21B of the above-described second embodiment, the magnetic layers 31A and 31B are constructed as radio wave absorbers made of an insulating material such as a synthetic resin filled with soft magnetic powder.

The magnetic layer 31A is formed on the front surface side of the circuit board 30, and the magnetic layer 31B is formed on the back surface side of the circuit board 30. The magnetic layers 31A and 31B are coupled together by a plurality of bridge portions 31C passing through the circuit board 30.

The magnetic layers 31A and 31B having the above-described structure may be magnetic sheets processed or formed into a sheet shape, but it is preferable to coat in a layer shape using a curable magnetic paste, a magnetic compound, or the like.

The magnetic layers 31A and 31B perform an operation of absorbing and canceling noise input to or output from the IC chip 2 of the IC card C3. In this embodiment, almost all the wiring regions except for the antenna pattern 1A are surrounded by the magnetic layers 31A and 31B and the bridge portion 31C to improve noise absorption efficiency.

In manufacturing the IC card C3 constructed as above, the through-hole 32 for forming the bridge portion 31C is formed to pass through the circuit board 30. In this case, the through hole 32 is preferably formed so that the magnetic layers 31A and 31B may surround the conductive pattern 1 in addition to the antenna pattern 1A.

After the IC chip 2 is mounted on the circuit board 30, the magnetic layers 31A and 31B are provided on the front and back surfaces of the circuit board 30. The magnetic layer is formed to fill the inside of the via hole 32. Similarly to the above-described first embodiment, the circuit board 30 is sandwiched by a plurality of card constituent sheets composed of a pair of inner core sheets and a pair of outer core sheets and formed into a card by hot pressing.

Relief holes are formed on the inner core sheets on the inner side to accommodate the magnetic layers 31A and 31B, so that the number of irregularities on the card surface is reduced after stacking the sheets, and the thickness of the card can be made thin.

If the magnetic layers 31A and 31B are made of a magnetic paste, the magnetic paste is subjected to a curing process after being applied, for example, together with the sealing resins 7A and 7B that seal the IC chip 2. If the magnetic layers 31A and 31B are made of a magnetic compound, after the magnetic compound is applied, the magnetic compound is subjected to a curing process while hot pressing for forming a card is performed.

According to the IC card C3 of this embodiment, similarly to the first embodiment, it is possible to eliminate noise output from and input to the IC chip 2 to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C3 can also be excluded.

According to this embodiment, compared with the first embodiment, welding or the like is not required. The manufacturing cost is reduced, the card can be more efficiently manufactured, and thus the product quality is stabilized.

[ fourth example ] A

Fig. 11-13 illustrate a fourth embodiment of the present invention. Fig. 11 is a cross-sectional view of the IC card C4 of the embodiment, fig. 12 is a plan view of the circuit board 40 constituting the IC card C4, and fig. 13 is a plan view showing the structure of the circuit board 40. In fig. 11 to 13, elements corresponding to those of the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, a noise absorber for absorbing and canceling noise input to or output from the IC chip 2 is constituted by a pair of magnetic layers 41A and 41B covering the wiring portions 12a and 12B. Similar to the magnetic layers 21A and 21B of the above-described second embodiment, the magnetic layers 41A and 41B are constructed as radio wave absorbers made of an insulating material such as a synthetic resin filled with soft magnetic powder.

The magnetic layer 41A is formed on the front surface side of the circuit board 40, and the magnetic layer 41B is formed on the back surface side of the circuit board 40. The magnetic layers 41A and 41B are coupled together by a plurality of bridge portions 41C that pass through the circuit board 40.

The magnetic layers 41A and 41B having the above-described structure may be magnetic sheets processed or formed into a sheet shape, but it is preferable to coat in a layer shape using a curable magnetic paste, a magnetic compound, or the like.

The magnetic layers 41A and 41B perform an operation of absorbing and canceling noise input to or output from the IC chip 2 of the IC card C4. In this embodiment, the wiring portions 12a and 12B interconnecting the antenna pattern 1A and the IC chip 2 are surrounded by the magnetic layers 41A and 41B and the bridge portion 41C to improve noise absorption efficiency.

In manufacturing the IC card C4 constructed as above, the through-hole 42 for forming the bridge portion 41C is formed to pass through the circuit board 40. In this case, the through hole 42 is preferably formed so that the magnetic layers 41A and 41B can surround the line portions 12a and 12B. It is preferable that the magnetic layers 41A and 41B be disposed near the IC chip 2.

After the IC chip 2 is mounted on the circuit board 40, the magnetic layers 41A and 41B are disposed on the front and back surfaces of the circuit board 40. The magnetic layer is formed to fill the inside of the via hole 42. Similarly to the above-described first embodiment, the circuit board 40 is sandwiched by a plurality of card constituent sheets composed of a pair of inner core sheets and a pair of outer core sheets and formed into a card by hot pressing.

Relief holes are formed on the inner core sheets on the inner side to accommodate the magnetic layers 41A and 41B, so that the number of irregularities on the card surface is reduced after stacking the sheets, and the thickness of the card can be made thin.

If the magnetic layers 41A and 41B are made of a magnetic paste, the magnetic paste is subjected to a curing process after being applied, for example, together with the sealing resins 7A and 7B that seal the IC chip 2. If the magnetic layers 41A and 41B are made of a magnetic compound, after the magnetic compound is applied, the magnetic compound is subjected to a curing process while hot pressing for forming a card is performed.

According to the IC card C4 of this embodiment, similarly to the first embodiment, it is possible to eliminate noise output from and input to the IC chip 2 to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C4 can also be excluded.

According to this embodiment, compared with the first embodiment, welding or the like is not required. The manufacturing cost is reduced, the card can be more efficiently manufactured, and thus the product quality is stabilized.

[ fifth embodiment ]

Fig. 14 and 15 illustrate a fifth embodiment of the present invention. Fig. 14 is a cross-sectional view of the IC card C5 of the embodiment, and fig. 15 is a plan view of the circuit board 50 constituting the IC card C5. In fig. 14 and 15, elements corresponding to those of the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, a noise absorber for absorbing and eliminating noise input to or output from the IC chip 2 is constituted by the sealing resins 51A and 51B for sealing the IC chip 2. The sealing resins 51A and 51B are constructed as radio wave absorbers, and are made of an insulating material such as a synthetic resin filled with soft magnetic powder.

In this embodiment, although the sealing resins 51A and 51B are constructed as radio wave absorbers, the sealing resin 51B on the back surface side of the chip may be constituted by a usual (non-magnetic) sealing material if necessary.

The sealing resins 51A and 51B perform an operation of absorbing and eliminating noise input to or output from the IC chip 2 of the IC card C2. In this embodiment, the sealing resin for sealing the IC chip 2 is made of a material having a radio wave absorbing property to obtain a noise absorbing and removing effect. Therefore, noise output from and input to the IC chip 2 can be eliminated to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C5 can also be excluded.

When the IC card C5 constructed as above is manufactured, the chip sealing material is replaced with the sealing resins 51A and 51B having the above-described radio wave absorption property, and a conventional IC card manufacturing process can be used without change.

[ sixth embodiment ]

Fig. 16-19 illustrate a sixth embodiment of the present invention. Fig. 16 is a cross-sectional view of the IC card C6 of the embodiment, fig. 17 is a plan view of the circuit board 60 constituting the IC card C6, fig. 18 is a plan view showing the structure of the circuit board 60, and fig. 19 is a side view of sintered magnetic materials 61A and 61B. In fig. 16 to 19, elements corresponding to those of the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, the noise absorber for absorbing and canceling noise input to or output from the IC chip 2 is constituted by a pair of sintered magnetic materials 61A and 61B, the sintered magnetic materials 61A and 61B surrounding the wiring portions 12a and 12B interconnecting the antenna pattern 1A and the IC chip 2.

In this embodiment, a pair of sintered magnetic materials 61A and 61B are provided in the regions of the wiring portions 12a and 12B sealed together with the IC chip 2 with the sealing resin 7A. The sintered magnetic materials 61A and 61B are also sealed by the sealing resin 7A.

The sintered magnetic materials 61A and 61B are formed by baking and solidifying a sintered powder mixed and stirred with soft magnetic powder. As shown in fig. 19, the legs 61C are formed at facing positions. The legs 61C and 61C of the sintered magnetic materials 61A and 61B abut at facing positions via through holes 62 (fig. 17 and 18) formed through the circuit board 60, thereby surrounding the areas of the wiring portions 12a and 12B near the IC chip 2 and improving the efficiency of absorbing noise input to and output from the IC chip.

According to the IC card C6 of this embodiment, similarly to the first embodiment, it is possible to eliminate noise output from and input to the IC chip 2 to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C6 can also be excluded.

Since the sintered magnetic materials 61A and 61B constituting the noise absorber are sealed together with the IC chip 2 with the sealing resin 7A, the brittleness of the sintered magnetic materials 61A and 61B is compensated, and the strength reliability is maintained.

[ seventh example ]

Fig. 20 and 21 illustrate a seventh embodiment of the present invention. Fig. 20 is a cross-sectional view of the IC card C7 of the embodiment, and fig. 21 is a plan view of the circuit board 70 constituting the IC card C7. In fig. 20 and 21, elements corresponding to those of the first embodiment are denoted by using the same reference numerals, and detailed description thereof is omitted.

In this embodiment, the noise absorber for absorbing and canceling noise input to or output from the IC chip 2 is constituted by a pair of chip-type ferrite beads 71A and 71b, the chip-type ferrite beads 71A and 71b being mounted on the wiring portions 12a and 12b interconnecting the antenna pattern 1A and the IC chip 2 by using a bonding material such as solders 73 and 73.

Specifically in this embodiment, a pair of ferrite beads 71a and 71b are mounted in the regions of the wiring portions 12a and 12b sealed together with the IC chip 2 with the sealing resin 7A. The ferrite beads 71a and 71b are also sealed with a sealing resin 7A.

The ferrite beads 71a and 71b have, similarly to the ferrite beads 11a and 11b described in the first embodiment, conductive layers partially constituting the wiring portions 12a and 12b and magnetic layers absorbing and canceling noises (unnecessary radiation energy) input to and output from the IC chip 2. In this embodiment, the ferrite beads 71a and 71b are sized to be able to be sealed with the sealing resin 7A.

According to the IC card C7 of this embodiment, it is possible to eliminate noise output from and input to the IC chip 2 to exclude adverse effects on the operation of peripheral devices. Magnetic interference with an electronic device placed near the IC card C7 can also be excluded.

The embodiments of the present invention have been described above, but it is apparent that the present invention is not limited to these embodiments, and various modifications are conceivable based on the technical idea of the present invention.

For example, in the above-described embodiment, a so-called card-size noncontact IC card is explained as an example of the IC card of the present invention. The present invention is not limited to this type of IC card, but may be applied to all IC media capable of reading/writing recorded information to an IC chip by using RFID technology, such as a noncontact IC tag and an ID tag attached to each product.

In these embodiments, the IC card is formed by sandwiching a circuit board using a plurality of card formation sheets and thermally pressing and bonding the sheets. Alternatively, the IC card may be formed by sandwiching a circuit board using a pair of coating sheets with a thermoplastic adhesive such as an epoxy resin system. The present invention can also be applied to this type of IC card.

Industrial applicability

As described above, according to the IC card of the present invention, since the noise absorber that absorbs and eliminates the noise component generated in the IC chip is provided, it is possible to absorb and eliminate the noise input to and output from the IC chip of the IC card, so that unnecessary radiation from the IC card is reduced and adverse effects on peripheral devices are also suppressed.

Claims (8)

1. An integrated circuit card formed by sandwiching a circuit board on which an antenna pattern is formed and an integrated circuit chip mounted on the circuit board using a plurality of card constituting sheets, characterized in that:

the circuit board is provided with a noise absorber for absorbing and canceling noise input to and output from the integrated circuit chip,

wherein the noise absorber does not cover the antenna pattern.

2. An integrated circuit card according to claim 1, characterized in that:

the noise absorber is disposed on a wiring region on a circuit board for interconnecting the antenna pattern and the integrated circuit chip.

3. An integrated circuit card according to claim 2, characterized in that:

the noise absorber is a chip-type ferrite bead mounted on a circuit board so as to partially constitute the wiring.

4. An integrated circuit card according to claim 2, characterized in that:

the noise absorber is a magnetic layer formed on the circuit board so as to partially cover the wiring region.

5. An integrated circuit card according to claim 4, characterized in that:

the magnetic layer is disposed through the circuit board so as to partially surround the wiring region.

6. An integrated circuit card according to claim 1, characterized in that:

the integrated circuit chip is sealed on the circuit board by a sealing resin; and

the noise absorber is formed by mixing and stirring the sealing resin with a magnetic material.

7. An integrated circuit card according to claim 1, characterized in that:

the integrated circuit chip is sealed on the circuit board by a sealing resin; and

the noise absorber is sealed together with the integrated circuit chip by the sealing resin.

8. A method of manufacturing an integrated circuit card including a step of mounting an integrated circuit chip on a circuit board on which an antenna pattern is formed, a step of sandwiching the circuit board on which the integrated circuit chip is mounted with a plurality of card-constituting sheets, said method of manufacturing an integrated circuit card being characterized in that:

a step of providing a noise absorber for absorbing and canceling noise input to and output from the integrated circuit chip on the circuit board, the noise absorber not covering the antenna pattern.