WO2007083575A1

WO2007083575A1 - Radio ic device

Info

Publication number: WO2007083575A1
Application number: PCT/JP2007/050309
Authority: WO
Inventors: Yuya Dokai; Noboru Kato; Satoshi Ishino
Original assignee: Murata Manufacturing Co., Ltd.
Priority date: 2006-01-19
Filing date: 2007-01-12
Publication date: 2007-07-26
Also published as: JP4123306B2; JPWO2007083575A1

Abstract

It is possible to provide a radio IC device on which a radio IC chip can be easily and accurately mounted and in which the resonance frequency characteristic is not changed. The radio IC device includes: a radio IC chip (5); a feed circuit substrate (10) having the radio IC chip (5) mounted thereon and a built-in feed circuit (16) connected to the radio IC chip (5) via a solder bump (6); and an emission plate (20) attached to the lower surface of the feed circuit substrate (10) and electromagnetically coupled to the feed circuit (16) by electromagnetic coupling. The feed circuit substrate (10) is formed by overlaying flexible sheets and the feed circuit (16) is formed by an LC resonance circuit having an inductance element (L) and a capacitance element (C).

Description

Specification

Wireless IC device

Technical field

The present invention relates to a wireless IC device, and more particularly to a wireless IC device used for an RFID (Radio Frequency Identification) system.

Background art

In recent years, as an article management system, a reader / writer that generates an induction electromagnetic field and an IC tag (hereinafter referred to as a wireless IC device) that stores predetermined information attached to the article are communicated in a non-contact manner. RFID systems that transmit information have been developed. As wireless IC devices used in RFID systems, for example, those described in Patent Documents 1 and 2 are known.

That is, as shown in FIG. 19, an antenna pattern 101 is provided on a plastic film 100, and a wireless IC chip 110 is attached to one end of the antenna pattern 101. As shown in FIG. An antenna pattern 121 and a radiation electrode 122 are provided thereon, and a wireless IC chip 110 is attached to a predetermined portion of the antenna pattern 121.

[0004] However, in the conventional wireless IC device, the wireless IC chip 110 is connected to and mounted on the antenna patterns 101 and 121 in a DC manner using Au bumps. The IC chip 110 needs to be positioned. However, it is extremely difficult to mount the small wireless IC chip 110 on the large-area films 100 and 120, and there is a problem that the resonance frequency characteristic of the antenna changes if a positional shift occurs during the mounting.

[0005] The resonance frequency characteristics of the antenna also change when the antenna patterns 101 and 121 are rounded or sandwiched between dielectrics (for example, sandwiched in a book).

Patent Document 1: Japanese Patent Laid-Open No. 2005-136528

Patent Document 2: Japanese Patent Laid-Open No. 2005-244778

Disclosure of the invention Problems to be solved by the invention

[0006] Accordingly, an object of the present invention is to provide a wireless IC device in which a wireless IC chip can be mounted easily and accurately, and the resonance frequency characteristic does not change. Means for solving the problem

In order to achieve the above object, a wireless IC device according to a first aspect of the present invention includes a wireless IC chip and a flexible substrate, is mounted with the wireless IC chip, and the wireless IC chip A power supply circuit board having a power supply circuit connected to the power supply circuit board, and a radiation plate that is directly or close to the power supply circuit board and is electromagnetically coupled to the power supply circuit.

[0008] In addition, a wireless IC device according to a second aspect of the present invention includes a wireless IC chip made of a flexible semiconductor, the wireless IC chip mounted thereon, and connected to the wireless IC chip. The power supply circuit board includes a power supply circuit board, and a radiation plate that is directly or close to the power supply circuit board and is electromagnetically coupled to the power supply circuit.

In the wireless IC device according to the present invention, the power feeding circuit is provided on the power feeding circuit board and is electromagnetically coupled to the radiation plate by electromagnetic coupling. The wireless IC chip is connected to a power supply circuit board provided with a power supply circuit, and the power supply circuit board has a considerably small area, so that the wireless IC chip can be mounted with extremely high accuracy. In addition, since the power supply circuit is provided on the power supply circuit board, the resonance frequency characteristics do not change even if the wireless IC device is rolled or sandwiched between dielectrics.

In the wireless IC device according to the present invention, the resonance frequency of the signal emitted from the radiation plate substantially corresponds to the self-resonance frequency of the power feeding circuit, and the maximum gain of the signal is It is substantially determined by at least one of the size and shape of the circuit, the distance between the feeding circuit and the radiation plate, and the medium. The electrical length of the radiation plate should be an integral multiple of half the wavelength at the resonance frequency.

[0011] The feeder circuit board can be formed of a flexible board. If the wireless IC chip or the power supply circuit board is flexible, it is easy to handle without being cracked or chipped. Furthermore, the radiation plate is preferably formed of a flexible metal film. ,. This flexible metal film is held by a flexible film.

[0012] The power supply circuit board can be composed of a multilayer substrate formed by laminating a plurality of dielectric layers or magnetic layers, and the power supply circuit can be easily incorporated in the multilayer substrate. In this case, the power supply circuit should be composed of an LC resonance circuit that also has an inductance element and a capacitance element force built into the multilayer substrate. The inductance element can be formed by a coiled electrode pattern made of a conductor.

[0013] The coiled electrode pattern constituting the inductance element may have a winding axis formed substantially parallel to the radiation plate or may be formed substantially perpendicularly. In the latter case, it is preferable that the winding width of the coiled electrode pattern is gradually increased toward the radiation plate.

The invention's effect

[0014] According to the present invention, the wireless IC chip can be mounted on the feeder circuit board with extremely high accuracy. In addition, since the feeder circuit is provided on the feeder circuit board, the resonance frequency characteristics do not change even if the wireless IC device is rolled or sandwiched between dielectrics.

Brief Description of Drawings

FIG. 1 is a perspective view showing a first embodiment of a wireless IC device according to the present invention.

FIG. 2 is a sectional view of the first embodiment.

FIG. 3 is an equivalent circuit diagram of the first embodiment.

[4] FIG. 4 is an exploded perspective view showing the feeder circuit board of the first embodiment.

FIG. 5 is a perspective view showing a second embodiment of the wireless IC device according to the present invention.

FIG. 6 is a cross-sectional view showing a third embodiment of the wireless IC device according to the present invention.

FIG. 7 is an equivalent circuit diagram showing a fourth embodiment of the wireless IC device according to the present invention.

FIG. 8 is an equivalent circuit diagram showing a fifth embodiment of a wireless IC device according to the present invention.

FIG. 9 is an equivalent circuit diagram showing a sixth embodiment of a wireless IC device according to the present invention.

FIG. 10 is a sectional view showing a seventh embodiment of a wireless IC device according to the present invention.

FIG. 11 is an equivalent circuit diagram of the seventh embodiment.

FIG. 12 is an exploded perspective view showing a feeder circuit board of the seventh embodiment.

FIG. 13 is an equivalent circuit diagram showing an eighth embodiment of the wireless IC device according to the present invention. FIG. 14 is an equivalent circuit diagram showing a ninth embodiment of a wireless IC device according to the present invention.

FIG. 15 is an exploded perspective view showing a power supply circuit board according to the ninth embodiment.

FIG. 16 is a perspective view showing a tenth embodiment of a wireless IC device according to the present invention.

FIG. 17 is a sectional view showing an eleventh embodiment of the wireless IC device according to the present invention.

FIG. 18 is an exploded perspective view showing the feeder circuit board of the eleventh embodiment.

FIG. 19 is a plan view showing a first example of a conventional wireless IC device.

FIG. 20 is a plan view showing a second example of a conventional wireless IC device.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of a wireless IC device according to the present invention will be described with reference to the accompanying drawings. In addition, parts and portions that are common in each embodiment described below are denoted by the same reference numerals, and redundant descriptions are omitted.

[0017] (Refer to the first embodiment, FIGS. 1 to 4)

The wireless IC device la according to the first embodiment is a monopole type, and as shown in FIGS. 1 and 2, a wireless IC chip 5 and a feeder circuit board 10 having the wireless IC chip 5 mounted on the upper surface, It is composed of a radiation plate 20 to which the feeder circuit board 10 is attached. The wireless IC chip 5 has the necessary information power and is directly connected to the power supply circuit 16 built in the power supply circuit board 10.

As shown in FIGS. 2 and 3, the power feeding circuit board 10 incorporates a power feeding circuit 16 configured by an LC series resonance circuit that also has an inductance element L and a capacitance element C force. Specifically, as shown in FIG. 4, the feeder circuit board 10 is formed by laminating and adhering flexible sheets 11A to 11G having dielectric strength such as polyimide or liquid crystal polymer, and forming the connection electrodes 12 and via-hole conductors 13a. Sheet 11A, sheet 11B with capacitor electrode 14a, sheet 11C with capacitor electrode 14b and via hole conductor 13b, sheet 11D with via hole conductor 13c, sheet 11E with conductor pattern 15a and via hole conductor 13d, via hole conductor A sheet 1 IF (a plurality of sheets) on which 13e is formed and a sheet 11G on which a conductor pattern 15b is formed. The sheets 11A to 11G are made of a dielectric or magnetic flexible material having a thickness of about 10 / zm, and a conductor pattern and a via-hole conductor can be formed on each sheet by a thick film forming process. Also laminated those sheets The power supply circuit board 10 can be easily obtained by bonding by thermocompression bonding or the like.

By laminating the above sheets 11A to 11G, the inductance element L whose winding axis is parallel to the radiation plate 20, the capacitor electrode 14b is connected to both ends of the inductance element L, and the capacitor electrode 14a A capacitance element C is formed in which is connected to the connection electrode 12 via the via-hole conductor 13a. Then, the connection electrode 12 is connected to the wireless IC chip 5 via the solder bump 6.

That is, among the elements constituting the power feeding circuit 16, a transmission signal is fed from the inductance element, which is a coiled electrode pattern, to the radiation plate 20 via a magnetic field, and the reception signal from the radiation plate 20 is also received. Is fed to the inductance element L via a magnetic field. Therefore, it is preferable that the power feeding circuit board 10 be laid out so that the inductance element is close to the radiation plate 20 among the inductance elements and capacitance elements constituting the resonance circuit.

The radiation plate 20 is a long body having nonmagnetic strength such as an aluminum foil, that is, a metal body with both ends open, and is formed on an insulating flexible film 21 such as PET. The lower surface of the power supply circuit board 10 is stuck on the radiation plate 20 via an adhesive 17.

As an example of the size, the wireless IC chip 5 has a thickness of 50 to 100 μm, the solder bump 6 has a thickness of about 20 m, and the feeder circuit board 10 has a thickness of 200 to 500 111, The thickness of the adhesive 17 is 0.1 to: LO μm, the thickness of the radiation plate 20 is 1 to 50 μm, and the thickness of the Finolem 21 is 10 to: LOO μm. Also, the size (area) of the wireless IC chip 5 is various, such as 0.4 mm X O. 4 mm, 0.9 mm X 0.8 mm. The size (area) of the power supply circuit board 10 can be configured from the same size as the wireless IC chip 5 to a size of about 3 mm × 3 mm.

FIG. 3 shows an equivalent circuit of the wireless IC device la. The wireless IC device la receives a high-frequency signal (for example, UHF frequency band) that is also radiated with a reader / writer force (not shown) by the radiation plate 20, and includes a feeding circuit 16 that is mainly magnetically coupled to the radiation plate 20. Resonate and supply only the received signal in the predetermined frequency band to the wireless IC chip 5. On the other hand, predetermined energy is extracted from this received signal, information stored in the wireless IC chip 5 is matched with a predetermined frequency by the power feeding circuit 16 using this energy as a driving source, and the inductance of the power feeding circuit 16 is matched. A transmission signal is transmitted from the element to the radiation plate 20 through magnetic field coupling, and transferred from the radiation plate 20 to the reader / writer. [0024] It should be noted that the power feeding circuit 16 and the radiation plate 20 may be coupled via a magnetic field (mainly electromagnetic field coupling), which is mainly coupled via a magnetic field.

[0025] In the wireless IC device la according to the first embodiment, the wireless IC chip 5 is directly connected to the feeder circuit board 10 including the feeder circuit 16, and the feeder circuit board 10 has a considerably small area. Therefore, it is possible to position and mount the wireless IC chip 5 with extremely high accuracy rather than mounting on a film having a large area as in the past.

In addition, the resonance frequency characteristic of the power feeding circuit 16 is determined by the inductance element L and the capacitance element C. The resonance frequency of the signal radiated from the radiation plate 20 substantially corresponds to the self-resonance frequency of the feeder circuit 16, and the maximum gain of the signal is the size and shape of the feeder circuit 16, the feeder circuit 16 and the radiation plate 20, And at least one of the distance and the medium. Specifically, in the first embodiment, the electrical length of the radiation plate 20 is 1Z2 having a wavelength λ corresponding to the resonance frequency. However, the electrical length of the radiation plate 20 may not be an integer multiple of λ 2. In other words, in the present invention, the frequency of the signal radiated from the radiation plate is substantially determined by the resonance frequency of the power feeding circuit constituting the resonance circuit, and therefore the frequency characteristic is substantially equal to the electrical length of the radiation plate. Does not depend on. It is preferable that the electrical length of the radiation plate is an integral multiple of λ 2 because the gain is maximized.

[0027] Since the resonance frequency characteristics of the power feeding circuit 16 are determined by the inductance element L and the capacitance element C built in the power feeding circuit board 10 as described above, the wireless IC device 1a is sandwiched between books. However, the resonance frequency characteristic does not change. Further, even if the wireless device la is rounded or the size of the radiation plate 20 is changed, the resonance frequency characteristic does not change. In addition, the coiled electrode pattern constituting the inductance element L has the advantage that the center frequency does not fluctuate because the winding axis is formed in parallel with the radiation plate 20. Further, since the capacitance element C is inserted in the subsequent stage of the wireless IC chip 5, the low frequency surge can be cut by this element C, and the surge resistance of the wireless IC chip 5 can be protected.

[0028] Furthermore, the feeder circuit board 10 is a flexible board, and the radiation plate 20 is formed of a flexible metal film held by the flexible film 21, so that, for example, a soft bag made of plastic film or a pet is used. Any obstacle to the cylindrical body like a bottle It can be stuck without.

[0029] Further, by manufacturing the feeder circuit board 10 with an organic material, it is possible to manufacture the feeder circuit board 10 at a low cost without the need for a baking process, and it is possible to reduce the height of the wireless IC device la by making the board thin overall. . In addition, when the wireless IC chip 5 is made of a flexible semiconductor, handling becomes easier and the number of objects to which the wireless IC device la is attached can be increased.

[0030] (Refer to the second embodiment, FIG. 5)

As shown in FIG. 5, the wireless IC device lb according to the second embodiment has a wide area radiation plate 20 formed of aluminum foil or the like on a flexible plastic film 21 having a large area of insulation. A feeding circuit board 10 on which the wireless IC chip 5 is mounted is bonded to an arbitrary position of the radiation plate 20.

[0031] The other configuration of the wireless IC device lb, that is, the internal configuration of the feeder circuit board 10 is the same as that of the first embodiment. Therefore, the operational effects of the second embodiment are basically the same as those of the first embodiment.

[0032] (Refer to the third embodiment, FIG. 6)

As shown in FIG. 6, the wireless IC device lc of the third embodiment has an adhesive 17 applied to the entire surface of the film 21 via a radiation plate 20. With this adhesive 17, the wireless IC device lc can be attached to any part of the article.

[0033] The other configuration of the wireless IC device lc, that is, the internal configuration of the feeder circuit board 10 is the same as that of the first embodiment. Therefore, the operational effects of the third embodiment are basically the same as those of the first embodiment.

[0034] (Example 4 see FIG. 7)

As shown in FIG. 7 as an equivalent circuit, the wireless IC device Id according to the fourth embodiment includes an inductance element L that also has a coiled electrode pattern force as a power feeding circuit 16 on an antenna substrate. The capacitance element C constituting the LC resonance circuit is formed as a stray capacitance (distributed constant type capacitance) between the conductor patterns of the inductance element L.

[0035] Even a single coiled electrode pattern has self-resonance! If it hits, it acts as an LC parallel resonant circuit with the L component of the coiled electrode pattern itself and the C component that is the floating capacitance between the lines. However, the power feeding circuit 16 can be configured. [0036] (Refer to the fifth embodiment, FIG. 8)

As shown in FIG. 8 as an equivalent circuit, the wireless IC device le according to the fifth embodiment is a device including a dipole type power feeding circuit 16 and a radiation plate 20, and a pair of LC parallel resonant circuits on the power feeding circuit board 10. Power supply circuits 16a and 16b that have power are incorporated. The power feeding circuit 16a is connected to the hot side of the wireless IC chip 5, and the power feeding circuit 16b is connected to the ground side of the wireless IC chip 5, and faces the radiation plates 20 and 20, respectively. The end of the feeder circuit 16a is an open end. The operation of the power supply circuits 16a and 16b having such LC parallel resonance circuit force is the same as that of the power supply circuit 16 including the LC series resonance circuit, and basically has the same effect as the first embodiment.

[0037] (See Example 6 and FIG. 9)

As shown in FIG. 9 as an equivalent circuit, the wireless IC device If according to the sixth embodiment is a device including a dipole-type power feeding circuit 16 and a radiation plate 20, and a pair of LC series resonance circuits on the power feeding circuit board 10. Power supply circuits 16a and 16b that have power are incorporated. Each feeder circuit 16a, 16b is opposed to the radiation plates 20, 20, and the capacitance element C is connected to the ground. The operation of the power supply circuits 16a and 16b having such LC series resonance circuit force is the same as that of the power supply circuit 16 including the LC series resonance circuit, and basically has the same effect as that of the first embodiment.

[0038] (Refer to the seventh embodiment, FIGS. 10 to 12)

As shown in FIG. 10, the wireless IC device lg according to the seventh embodiment is a monopole type, and a power supply circuit having an LC series resonance circuit force with an inductance element L and a capacitance element C built in the power supply circuit board 10. 16 is composed. As shown in FIG. 11, the coiled electrode pattern constituting the inductance element L has a winding axis formed perpendicular to the radiation plate 20, and the feeder circuit 16 is mainly magnetically coupled to the radiation plate 20. .

[0039] Specifically, as shown in FIG. 12, the feeder circuit board 10 is formed by laminating and adhering flexible sheets 31A to 31F made of a dielectric material such as polyimide or liquid crystal polymer. Sheet 31A with 32 and via-hole conductor 33a, sheet 31B with capacitor electrode 34a and via-hole conductor 33b, sheet 31C with capacitor electrode 34b and via-hole conductors 33c and 33b, conductor pattern 35a and via-hole conductors 33d and 33b Formed sheet 31D (multiple sheets), sheet 31E (multiple sheets) on which conductor pattern 35b and via-hole conductors 33e and 33b are formed, and sheet 31F force on which conductor pattern 35c is formed are also provided.

[0040] By laminating the above sheets 31A to 31F, an inductance element L whose winding axis is perpendicular to the radiation plate 20, and an LC resonance circuit force in which a capacitance element C is connected in series with the inductance element L are also obtained. A feed circuit 16 is obtained. The capacitor electrode 34a is connected to the connection electrode 32 via the via-hole conductor 33a, and further connected to the wireless IC chip 5 via the solder bump 6, and one end of the inductance element L is connected to the connection electrode 32 via the via-hole conductor 33b. And is further connected to the wireless IC chip 5 via the solder bump 6.

[0041] The operation of the power supply circuit 16 having the LC series resonance circuit force is the same as that of the power supply circuit 16 having the LC series resonance circuit force, and basically has the same effect as the first embodiment. In particular, in the seventh embodiment, the coiled electrode pattern has its winding axis formed perpendicular to the radiation plate 20, so that the magnetic flux component to the radiation plate 20 increases and the transmission efficiency of signal energy increases. It has the advantage of being improved and having a large gain.

[0042] (Refer to the eighth embodiment, FIG. 13)

The wireless IC device lh according to the eighth embodiment has a winding width (coil diameter) of the coiled electrode pattern of the inductance element L shown in the seventh embodiment as shown in FIG. 13 as an equivalent circuit. It is gradually formed larger. Other configurations are the same as those of the seventh embodiment.

The eighth embodiment has the same effect as the seventh embodiment, and the winding width (coil diameter) of the coiled electrode pattern of the inductance element L gradually increases toward the radiation plate 20. Since it is formed large, signal transmission efficiency is improved.

[0044] (Refer to the ninth embodiment, FIG. 14 and FIG. 15)

The wireless IC device li according to the ninth embodiment is a dipole type as shown in FIG. 14 as an equivalent circuit, and includes a power supply circuit board 10 including a pair of power supply circuits 16 a and 16 b that also have a pair of LC series resonance circuit forces. It is.

[0045] In detail, as shown in FIG. 15, the feeder circuit board 10 is formed by laminating and adhering flexible sheets 41A to 41F made of a dielectric material such as polyimide liquid crystal polymer. And a sheet 41A on which via-hole conductors 43a are formed, and a sheet on which capacitor electrodes 44a are formed. 41B, sheet 41C with capacitor electrode 44b and via-hole conductor 43b, sheet 41D with conductor pattern 45a and via-hole conductor 43c (multiple sheets), sheet 41E with conductor pattern 45b and via-hole conductor 43d (multiple sheets) Sheet), the conductor pattern 45c formed on the first 41F force.

By laminating the above sheets 41A to 41F, an inductance element L whose winding axis is perpendicular to the radiation plate 20 and an LC resonance circuit force in which a capacitance element C is connected in series with the inductance element L are also obtained. Feed circuits 16a and 16b are obtained. The capacitor electrode 44a is connected to the connection electrode 42 via the via hole conductor 43a, and further connected to the wireless IC chip 5 via the solder bump.

[0047] The operation of the power supply circuits 16a and 16b having such a pair of LC series resonance circuit forces is the same as that of the power supply circuit 16 including the LC series resonance circuit, and is basically the same as in the first and seventh embodiments. Has the effect of.

[0048] (See the tenth embodiment, FIG. 16)

As shown in FIG. 16, the wireless IC device lj according to the tenth embodiment is a device in which a power feeding circuit 56 having a coiled electrode pattern force is provided on the surface of a flexible power feeding circuit board 50 made of heat-resistant grease. is there. Both ends of the power feeding circuit 56 are directly connected to the wireless IC chip 5 via solder bumps, and the power feeding circuit board 50 is adhered to the film 21 holding the radiation plate 20 with an adhesive. In addition, the conductor patterns 56a, 56b, and 56c that constitute the power feeding circuit 56 that intersect with each other are separated by an insulating film (not shown).

In the wireless IC device lj according to the tenth embodiment, the feeder circuit 56 is mainly magnetically coupled to the radiation plate 20. Accordingly, as in the above embodiments, the high-frequency signal emitted from the reader / writer is received by the radiation plate 20, the power feeding circuit 56 is resonated, and only the received signal in a predetermined frequency band is supplied to the wireless IC chip 5. . On the other hand, a predetermined energy is extracted from this received signal, and information stored in the wireless IC chip 5 using this energy as a drive source is matched to a predetermined frequency by the power feeding circuit 56, and A transmission signal is transmitted from the inductance element to the radiation plate 20 through magnetic field coupling, and then transmitted from the radiation plate 20 to the reader / writer.

[0050] The front side of the feeder circuit 56 is provided on the feeder circuit board 50 having a small area. As in the first embodiment, the positioning accuracy is good, and the wireless IC chip 5 can be connected by solder bumps.

[0051] (Refer to the eleventh embodiment, FIG. 17 and FIG. 18)

As shown in FIG. 17, the wireless IC device lk according to the eleventh embodiment has a coil-shaped electrode pattern of the power feeding circuit 56 built in the power feeding circuit board 50. As shown in FIG. 18, the feeder circuit board 50 is formed by laminating and adhering flexible sheets 51A to 51D having a dielectric force such as polyimide or liquid crystal polymer, and forming a connection electrode 52 and a via hole conductor 53a. Sheet 51 A, sheet 51 B on which conductor pattern 54 a and via-hole conductors 53 b and 53 c are formed, sheet 51 C on which conductor pattern 54 b is formed, and plain sheet 5 ID (plural sheets).

[0052] By laminating the above sheets 51A to 51D, a power supply circuit board 50 having a coil-shaped power supply circuit 56 is obtained, and the connection electrodes 52 located at both ends of the power supply circuit 56 are connected to the solder bump 6. To the wireless IC chip 5 via The operational effects of the eleventh embodiment are the same as those of the tenth embodiment.

[0053] (Another embodiment)

Note that the wireless IC device according to the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist thereof.

[0054] For example, the details of the internal configuration of the feeder circuit board and the details of the radiation plate and the resin film are arbitrary. In addition, processing other than solder bumps may be used to connect the wireless IC chip on the power supply circuit board.

[0055] Further, in each of the above-described embodiments, an example in which the feeder circuit board is directly attached to the radiation plate is shown. The force feeder circuit board may be disposed at a position close to the radiation plate. .

Industrial application fields

As described above, the present invention is useful for a wireless IC device used in an RFID system, and particularly excellent in that a wireless IC chip can be easily and accurately mounted and the resonance frequency characteristics do not change. ing.

Claims

The scope of the claims

[1] Wireless IC chip,

A power supply circuit board that is configured by a flexible substrate, has the wireless IC chip mounted thereon, and has a power supply circuit connected to the wireless IC chip;

A radiation plate that is disposed directly or close to the feeder circuit board and electromagnetically coupled to the feeder circuit;

A wireless IC device characterized by comprising:

[2] A wireless IC chip composed of a flexible semiconductor,

A power supply circuit board on which the wireless IC chip is mounted and having a power supply circuit connected to the wireless IC chip;

A wireless IC device characterized by comprising:

[3] The wireless IC device according to claim 2, wherein the feeder circuit board is a flexible board.

[4] The resonance frequency of the signal radiated from the radiation plate substantially corresponds to the self-resonance frequency of the feeder circuit,

The maximum gain of the signal is substantially determined by at least one of the size and shape of the feeder circuit, the distance between the feeder circuit and the radiation plate, and the medium;

A wireless IC device according to any one of claims 1 to 3, characterized in that:

5. The wireless IC device according to claim 4, wherein the electrical length of the radiation plate is an integral multiple of a half wavelength at the resonance frequency.

[6] The flexible substrate according to claim 1, wherein the flexible substrate is made of organic material.

V, and the wireless IC device according to any one of the fifth item.

7. The wireless IC device according to any one of claims 1 and 6, wherein the radiation plate is formed of a flexible metal film.

[8] The wireless IC device according to claim 7, wherein the flexible metal film is held by a flexible film.

[9] The power supply circuit board is a multilayer substrate formed by laminating a plurality of dielectric layers or magnetic layers, and the power supply circuit is built in the multilayer substrate.

The wireless IC device according to any one of Items 1 and 8 above.

10. The wireless IC device according to claim 9, wherein the power feeding circuit is configured by an LC resonance circuit having an inductance element and a capacitance element force built in the multilayer substrate.

11. The wireless IC device according to claim 10, wherein the inductance element is formed by a coiled electrode pattern made of a conductor.

[12] The coiled electrode pattern has a winding axis formed substantially parallel to the radiation plate.

12. The wireless IC device according to claim 11, wherein the wireless IC device is V.

[13] The coiled electrode pattern has a winding axis formed substantially perpendicular to the radiation plate.

14. The wireless IC device according to claim 13, wherein the coiled electrode pattern is formed so that a winding width is gradually increased toward the radiation plate.