JP2012014223A - Antenna sheet and information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology with which an IC chip can be protected without requiring much cost and labor.SOLUTION: An antenna sheet 10 comprises: a film substrate 11; an antenna coil 12 provided on a front surface of the film substrate 11; an IC chip 13 which is provided on the front surface of the film substrate 11 and connected to the antenna coil 12; a jumper wire 14 which is provided at a position on a rear surface of the film substrate 11 so that at least one part of the jumper wire 14 overlaps with the IC chip 13 in the thickness direction, and connects one end 12-1 of the antenna coil 12 and the other end 12-2 of the antenna coil 12. Making the jumper wire 14 have function of reinforcing the IC chip 13 can eliminate a conventional reinforcing plate, decrease the number of components, and simplify manufacturing process accordingly.

Description

  The present invention relates to an antenna sheet including an antenna coil and an IC chip on the surface of a film substrate, and an information recording medium including the antenna sheet.

  Conventionally, an antenna sheet used for a non-contact IC card or the like has a form in which a spiral antenna coil is formed on one surface of a film substrate. In general, as the antenna coil has a larger area (so-called opening area), communication efficiency (sensitivity) can be increased. Therefore, an antenna pattern is often formed along the outer periphery of the film substrate.

  The antenna coil is formed in a planar shape on the film substrate, and the IC chip is attached on the film substrate so as to be connected to both pole portions of the antenna coil. At this time, since the antenna coils are formed in a planar shape, they cannot intersect on the film substrate. Therefore, in order to electrically connect the two pole portions of the antenna coil and the IC chip, it is necessary to form a jumper wire that serves as a bridge on the back surface of the film substrate.

  As a technique using such a jumper wire, an antenna coil is formed on the surface of the film substrate, and a jumper wire that secures a certain area is formed at a position opposite to the antenna coil on the back surface of the film substrate. There is a technology (for example, see Patent Document 1).

  According to this technology, a capacitor having the antenna coil on the front surface and the jumper wire on the back surface as a counter electrode can be formed. Therefore, even after the jumper wire pattern is formed, a part of the jumper wire is cut off with a cutter or the like. By changing the line width (area) of the line, the capacitance of the capacitor can be changed, and the resonance frequency can be finely adjusted. As a result, it is considered that a contactless IC card and a tag having excellent communication characteristics can be provided.

JP 2002-49903 A

  By the way, if the IC chip is bent, it causes a failure. Further, the IC chip needs to be reinforced because it is vulnerable to impacts even after being carded. Furthermore, since the IC chip is not particularly protected in the state of the antenna sheet before it becomes an IC card, that is, in the state of the antenna sheet being manufactured, careful handling is necessary for handling the antenna sheet (particularly the IC chip). It is. This is the same for the above-described prior art, and no measures are taken for the handling of the antenna sheet.

  Therefore, in order to protect the IC chip arranged on the antenna sheet, a method of making the IC chip difficult to bend by attaching a reinforcing plate to the back side of the area of the antenna sheet where the IC chip is arranged and increasing the strength of the part. There is. With this method, since the IC chip is difficult to bend by attaching the reinforcing plate, a certain effect of protecting the IC chip can be obtained.

  However, when such a method is adopted, the antenna coil can be formed at once by printing silver paste or the like by screen printing. However, since the jumper wire and the reinforcing plate are separate parts, two parts are prepared separately. It must be costly. Moreover, since it is necessary to attach two components, two additional processes are required, and the manufacturing process takes time.

  Therefore, the present invention intends to provide a technique capable of protecting an IC chip without cost and effort.

  In order to solve the above problems, the present invention first provides an antenna sheet. Secondly, the present invention provides an information recording medium provided with an antenna sheet.

[Antenna sheet]
The antenna sheet of the present invention includes a film substrate, an antenna coil formed on the surface of the film substrate, an IC chip disposed on the surface of the film substrate and connected to the antenna coil, and a rear surface of the film substrate, at least A part of the antenna chip is disposed at a position overlapping with the IC chip in the thickness direction, and is provided by sticking a jumper wire that connects one end of the antenna coil and the other end of the antenna coil.

  According to the present invention, since the jumper wire is arranged at a position overlapping the IC chip in the thickness direction, the jumper wire has a function of protecting the IC chip as well as a function of electrically connecting one end and the other end of the antenna coil on the surface. Will also fulfill.

  Thus, by providing the jumper wire with a function of protecting the IC chip, the conventional reinforcing plate for protecting the IC chip is not necessary, and the manufacturing cost can be suppressed by reducing the number of components.

  In addition, in the conventional method, two steps of forming a jumper wire and forming a reinforcing plate are necessary. However, the jumper wire of the present invention combines the function of conduction and the function of the reinforcing plate. Therefore, only one step of forming the jumper line is required, and the manufacturing process can be simplified.

  As a configuration of the antenna sheet, it is preferable that the jumper line has a line width wider than the width of the IC chip, and the entire area of the IC chip overlaps the jumper line in the thickness direction.

  With this configuration, since the entire area of the IC chip overlaps with the jumper line in the thickness direction, the entire area of the IC chip is protected by the jumper line, and the protection of the IC chip can be enhanced.

  As a configuration of the antenna sheet, it is preferable that the jumper wire has a narrower line width of a portion overlapping with the antenna coil formed on the surface of the film substrate than a portion arranged at a position overlapping with the IC chip in the thickness direction. .

  Since the antenna coil is formed on the front surface of the film substrate and the jumper wire is formed on the back surface of the film substrate, the antenna coil and the jumper wire are overlapped in the thickness direction of the film substrate. At this time, since the antenna coil and the jumper wire are opposed to each other, a capacitor is formed using each as a counter electrode. It is also assumed that the original capacitance value fluctuates due to this capacitor and adversely affects the resonance frequency.

So, if it is said aspect, about the jumper wire, the line width of the part which overlaps with the antenna coil formed in the surface of the film substrate in the thickness direction, and the line width of the part arrange | positioned in the position which overlaps with an IC chip in the thickness direction By making it narrower, the facing area between the antenna coil and the jumper wire is also narrowed, and the electrostatic capacity stored by the capacitor having the antenna coil and the jumper wire as the counter electrode can be minimized.
In this way, by suppressing an unintended increase in capacitance to a minimum, it is possible to provide an antenna sheet that is less susceptible to fluctuations in the resonance frequency and has excellent antenna performance and communication characteristics.

[Information recording medium]
The information recording medium of the present invention includes the above-described antenna sheet.

  According to the present invention, since the effect of the antenna sheet described above can be obtained by using the information recording medium including the antenna sheet described above, it is possible to provide an information recording medium with low cost and stable quality.

  According to the present invention, by providing the jumper wire with the function of a reinforcing plate, a conventional reinforcing plate can be eliminated, and the manufacturing process can be simplified correspondingly while reducing the number of components.

It is a figure which shows the antenna sheet which concerns on 1st Embodiment of this invention. It is the enlarged view which expanded and showed IC chip 13 vicinity. It is sectional drawing which shows the III-III cross section of FIG. It is a disassembled perspective view which shows the IC card provided with the antenna sheet which concerns on 1st Embodiment of this invention. It is a figure which shows 10 A of antenna sheets of a comparative example. It is a figure which shows the AA cross section and BB cross section of FIG. It is process drawing explaining the manufacturing process of an antenna sheet. It is a figure which shows the antenna sheet | seat which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the antenna sheet and the information recording medium of the present invention will be described.
[First Embodiment]
FIG. 1 is a diagram showing an antenna sheet according to the first embodiment of the present invention.
The antenna sheet 10 has a film substrate 11 formed of, for example, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PET-G (amorphous polyethylene terephthalate), or the like.

  On the surface of the film substrate 11, an antenna coil (antenna wire) 12 wound about three times along the outer periphery of the film substrate 11 is formed. The number of turns of the antenna coil 12 may be three or less or three or more, and can be appropriately changed depending on the specification or design.

  The antenna coil 12 is formed by attaching an aluminum foil or a copper foil to the film substrate 11 and forming a coil shape by etching, a method of forming a coil shape by printing silver paste by screen printing, or a coil shape by drawing a wire. And a method of forming a coil shape by transferring a transfer foil for an antenna coil. The line width of the antenna coil 12 is, for example, about 0.5 to 1.0 mm.

  An IC chip 13 connected to the antenna coil 12 is disposed on the surface of the film substrate 11. The IC chip 13 is a chip on which a semiconductor memory such as a CPU, RAM, ROM, or EEPROM is mounted, and is sealed with a resin or the like.

FIG. 2 is an enlarged view showing the vicinity of the IC chip 13 in an enlarged manner.
A jumper wire 14 is formed on the back surface of the film substrate 11 (the jumper wire 14 is indicated by a broken line in FIG. 2). The jumper wire 14 is a substantially rectangular member whose both ends are rounded in an arc shape. A part of the jumper wire 14 is arranged at a position where it overlaps the IC chip 13 in the thickness direction of the film substrate 11. By disposing the jumper wire 14 at a position overlapping the IC chip 13 in the thickness direction, the jumper wire 14 can have a function of reinforcing the IC chip 13. The jumper line 14 has a line width wider than the width of the IC chip 13, and the entire area of the IC chip 13 overlaps the jumper line 14 in the thickness direction. As a result, the entire area of the IC chip 13 is protected by the jumper wire 14, and the protection of the IC chip 13 can be strengthened.

  On the other hand, the antenna coil 12 formed on the surface of the film substrate 11 has a first land portion 12-1 at one end and a second land portion 12-2 at the other end. The first land portion 12-1 is arranged at the upper right corner portion of the film substrate 11, and a continuous spiral antenna wire is drawn from the first land portion 12-1 toward the inner side of the film substrate 11, A second land portion 12-2 is formed at a point that makes three turns along the outer periphery of the film substrate 11.

The first through hole 15-1 is disposed in the first land portion 12-1, and the second through hole 15-2 and the IC chip 13 are disposed in the second land portion 12-2.
Since the first land portion 12-1 and the second land portion 12-2 are provided with through holes and the like, a relatively wide area is secured, and the first land portion 12-1 and the second land portion 12-2 are secured. Is formed as an antenna line thinner than the first land portion 12-1 and the second land portion 12-2. For example, when the 2 mm square IC chip 13 is arranged, the line width of the jumper line is preferably 2 mm or more. The thickness of the jumper wire is preferably 50 μm or more.

3 is a cross-sectional view showing a cross section taken along the line III-III in FIG.
As described above, two through holes (through holes) 15-1 and 15-2 are formed in the film substrate 11. The antenna coil 12 formed on the front surface of the film substrate 11 and the jumper wire 14 formed on the back surface of the film substrate 11 are connected by through holes 15-1 and 15-2. The jumper wire 14 electrically connects the one end 12-1 of the antenna coil 12 and the other end 12-2 of the antenna coil 12 through a conductive material filled in the two through holes 15-1 and 15-2. Connecting.

Here, the combined thickness of the jumper wire 14, the film substrate 11, and the IC chip 13 needs to be sufficiently thinner than the thickness of the IC card that is the final product. The thickness of the jumper wire 14 also depends on the thicknesses of the other IC chip 13 and the film substrate 11. However, if the thickness of the jumper wire 14 is too thin, it will not be able to withstand impacts from the outside. Conversely, if it is too thick, the card surface will become uneven when it is carded as a product. In view of such circumstances, the most suitable thickness of the jumper wire 14 is about 50 μm.
Further, since the jumper wire 14 plays a role of protecting the IC chip 13, it is preferable that the jumper wire 14 be made of a material that can ensure an appropriate rigidity even if the thickness is reduced to a certain extent. Moreover, since the jumper wire 14 also plays a role of conducting the antenna coil 12 on the surface, the material needs to have an appropriate conductivity. Specifically, materials such as aluminum, copper, and SUS304 are more preferable. Further, when the line width of the jumper line 14 is equal to or larger than the width of the IC chip 13, the strength of the IC chip 13 is further increased.

FIG. 4 is an exploded perspective view showing an IC card including the antenna sheet according to the first embodiment of the present invention.
The IC card 100 is a non-contact / contact type IC card which is an example of an information recording medium, and the antenna sheet 10 described above is sandwiched between card bases 101 such as PET. The non-contact type function is realized by the looped antenna coil or the like of the antenna sheet 10 described above, and the contact type function is realized by the contact terminal 102 or the like arranged on the card base 101. Although not particularly illustrated, an IC chip is also connected to the contact terminal 102. Further, the IC card may have only a non-contact function. Here, a non-contact type / contact type IC card (so-called combination card) is cited as an example of the information recording medium, but other examples include a non-contact IC card and a non-contact IC tag. it can.

FIG. 5 is a diagram showing an antenna sheet 10A of a comparative example, and FIG. 6 is a diagram showing an AA cross section and a BB cross section of FIG.
As shown in FIG. 5, the antenna sheet 10A of the comparative example includes a film substrate 11A, an antenna coil 12A formed on the surface of the film substrate 11A, an IC chip 13A connected to the antenna coil 12A, and an IC chip 13A. A reinforcing plate 20 disposed on the back surface and a jumper wire 14A for connecting one end and the other end of the antenna coil 12A to the back surface of the film substrate 11A through through holes 15-1A and 15-2A are provided.
The IC chip 13A is disposed near the upper left corner of the film substrate 11A, and the jumper wire 14A is disposed near the lower right corner of the film substrate 11A.

As shown in FIG. 6A, the antenna coil 12A formed on the surface of the film substrate 11A and the jumper wire 14A formed on the back surface of the film substrate 11A fill the through holes 15-1A and 15-2A. Are connected via a conductive material.
As shown in FIG. 6B, a reinforcing plate 20 is disposed on the back side of the IC chip 13A.

  Thus, in the antenna sheet 10A of the comparative example, two parts, that is, the reinforcing plate 20 and the jumper wire 14A are necessary, and the cost increases accordingly.

Next, the manufacturing process of the antenna sheet 10 according to the first embodiment will be described while comparing the process of this embodiment and the process of the comparative example.
FIG. 7 is a process diagram for explaining the manufacturing process of the antenna sheet. FIG. 7A is a process diagram of the antenna sheet 10 according to the first embodiment, and FIG. 7B is a process diagram of the antenna sheet 10A according to the comparative example.
First, the manufacturing process of the antenna sheet 10 according to the first embodiment will be described.

[Antenna coil forming step: see step S100 in FIG. 7A]
In this step, the antenna coil 12 is formed by printing a silver paste by screen printing on the surface of the film substrate 11 made of, for example, PET-G.

[Through hole forming step: see step S110 in FIG. 7A]
In this step, through holes 15-1 and 15-2 are formed at one end and the other end (first and second land portions 12-1 and 12-2) of the antenna coil 12.

[Jumper line forming step: see step S120 in FIG. 7A]
In this step, the jumper wire 14 is attached to the back surface of the film substrate 11.

[Through hole filling step: see step S130 in FIG. 7A]
In this step, a silver paste is filled into the through holes 15-1 and 15-2.

[IC chip mounting process: see step S140 in FIG. 7A]
In this step, the IC chip 13 is mounted at a predetermined position on the antenna coil 12 on the surface of the film substrate 11.
Through the above steps, the antenna sheet 10 of the first embodiment is completed.

Next, a manufacturing process of the antenna sheet 10A according to the comparative example will be described.
[Antenna coil forming step: see step S200 in FIG. 7B]
In this step, the antenna coil 12A is formed by printing a silver paste by screen printing on the surface of the film substrate 11A made of, for example, PET-G. This process is the same as step S100.

[Jumper line forming step: see step S210 in FIG. 7B]
In this step, the jumper wire 14A is formed on the back surface of the film substrate 11A by printing a silver paste by screen printing.

[Through hole forming step: see step S220 in FIG. 7B]
In this step, through holes 15-1A and 15-2A are formed at one end and the other end of the antenna coil 12A.
Regarding step S210 and step S220, compared with step S110 and step S120, both processes are interchanged, but the content is not substantially changed.

[Through hole filling step: see step S230 in FIG. 7B]
In this step, a silver paste is filled into the through holes 15-1A and 15-2A. This process is the same as step S130.

[Reinforcing plate pasting step: see step S235 in FIG. 7B]
In this step, the reinforcing plate 20 is mounted on the back surface of the film substrate 11A and at a position overlapping the IC chip 13A in the thickness direction. This step is not a step in the step of the first embodiment.

[IC chip mounting process: see step S240 in FIG. 7B]
In this step, the IC chip 13A is mounted at a predetermined position on the antenna coil 12A on the surface of the film substrate 11A. This process is the same as step S140.

  From the above description of the manufacturing process, by using the configuration of the present embodiment, step S235 of the manufacturing process of the comparative example can be omitted, and the manufacturing process can be simplified.

  As described above, according to the antenna sheet 10 of the first embodiment, the jumper wire 14 is formed at a position overlapping the IC chip 13 in the thickness direction, so that the jumper wire 14 only has a function of conducting the antenna coil 12 on the surface. In addition, the IC chip 13 is protected. Therefore, the number of parts corresponding to the conventional reinforcing plate 20 can be reduced, and the manufacturing process can be simplified by reducing the steps of forming the reinforcing plate 20.

  Further, according to the IC card 100 of the first embodiment, since the antenna sheet 10 manufactured by reducing the number of parts and the number of manufacturing steps is provided, the inexpensive IC card 100 is provided while maintaining the quality of the antenna sheet. Can do.

[Second Embodiment]
FIG. 8 is a diagram showing an antenna sheet according to the second embodiment of the present invention. In the following description, the same reference numerals are given to matters common to the first embodiment, and the redundant description thereof is omitted as appropriate.
The antenna sheet 10-2 according to the second embodiment is different from that of the first embodiment in the shape of the jumper wire 14-2.

The shape of the jumper wire 14-2 is a shape in which two substantially circular shapes are connected by one thin line, as shown in FIG.
Therefore, as shown in FIG. 8B, the line width of a portion of the jumper wire 14-2 that overlaps with the antenna coil 12 formed on the surface of the film substrate 11 in the thickness direction (a portion that intersects when viewed from the front). X1 is narrower than the line width X2 of the part formed in the position which overlaps with the IC chip 13 in the thickness direction.

  Thus, according to the second embodiment, a portion overlapping the IC chip 13 in the thickness direction is protected by the jumper wire 14-2 having a wide line width, while a portion overlapping the antenna coil 12 in the thickness direction is jumpered. By reducing the line width of the line 14-2, it is possible to prevent the capacitance from being increased unnecessarily, minimizing the fluctuation of the resonance frequency, and the antenna sheet 10-2 having excellent antenna performance and communication characteristics. Can be provided.

  In the second embodiment, as a protection function of the jumper line 14-2, it is sufficient that the IC chip 13 can be protected at a minimum. Therefore, the jumper line 14-2 is formed at a position overlapping the IC chip 13 in the thickness direction. The part other than the part may be a narrow jumper line.

  The present invention can be implemented with various modifications and substitutions without being limited to the above-described embodiment. The information recording medium of the present invention has been described with reference to an IC card, but may be an IC tag or the like. Further, the configurations of the antenna sheet and the IC card mentioned in the embodiment are all preferable examples, and it goes without saying that they can be implemented by appropriately modifying them.

10, 10-2 Antenna sheet 11 Film substrate 12 Antenna coil 12-1 First land portion 12-2 Second land portion 13 IC chip 14, 14-2 Jumper wire 15-1 First through hole 15-2 Second through Hall 100 IC card (information recording medium)
101 Card base material 102 Contact terminal

Claims (4)

A film substrate;
An antenna coil formed on the surface of the film substrate;
An IC chip disposed on the surface of the film substrate and connected to the antenna coil;
An antenna sheet provided with a jumper wire that is disposed on the back surface of the film substrate at a position where at least a part thereof overlaps with the IC chip in the thickness direction and connects one end of the antenna coil and the other end of the antenna coil. . In the antenna sheet according to claim 1,
The jumper line has a line width wider than the width of the IC chip,
An antenna sheet, wherein the entire area of the IC chip overlaps with the jumper wire in the thickness direction. In the antenna sheet according to claim 1 or 2,
The jumper wire is
An antenna sheet, wherein a line width of a portion overlapping the antenna coil formed on a surface of the film substrate is narrower than a line width of a portion arranged at a position overlapping the IC chip in a thickness direction.   An information recording medium comprising the antenna sheet according to any one of claims 1 to 3.