JP2005025514A - Conductive sheet for non-contact ic card with built-in antenna, and non-contact ic card with built-in antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive sheet for a non-contact IC card with a built-in antenna whose electric connectivity is highly reliable, whose circuit pattern formation is satisfactory, and whose producing efficiency is satisfactory. <P>SOLUTION: This conductive sheet for a non-contact IC card with a built-in antenna is constituted by forming conductive layers on both faces of an insulating substrate, and electrically connecting the conductive layers on both faces through a through-hole or via-hole opened so as to be put through the insulating substrate. The conductive layers are directly formed on the insulating substrate, and configured in the same way on the wall face of the through-hole or the inside of the via-hole and on both faces of the insulating substrate, and the conductive layers constitutes a circuit including an antenna. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a conductive sheet for a non-contact type IC card with a built-in antenna and a non-contact type IC card with a built-in antenna using the conductive sheet.
[0002]
[Prior art]
In recent years, integrated circuits (IC chips and LSIs) such as microcomputers and various memories are mounted on plastic cards, and signals, power supplies, clocks, etc. are exchanged in a non-contact state with external devices via antennas. Contact IC cards are used for various purposes.
[0003]
The conductive sheet used as the base of such a non-contact IC card with a built-in antenna usually forms a conductive layer on both the front and back sides of the insulating base, and the conductive layers on both the front and back sides are electrically connected via through holes and via holes. It has the structure of connecting to. For example, as such a conductive sheet, a structure in which a conductive layer is formed on the wall surface of the through hole by a vapor deposition method, and thereby a conductive layer such as a copper foil formed on the surface of the insulating base is electrically connected. Is known (Patent Document 1).
[0004]
However, in the conductive sheet having such a configuration, since the copper foil constituting the conductive layer is bonded to the insulating substrate with an adhesive, the electrical connectivity deteriorates due to the influence of the adhesive. There is a problem that the pattern formability deteriorates.
[0005]
Further, in such a conductive sheet, the configuration of the conductive layer on the insulating substrate and the conductive layer in the through hole is completely different and lacks in unity, so that reliable electrical connection could not be guaranteed. . Moreover, since these both conductive layers are manufactured through completely independent forming steps, the production efficiency is deteriorated.
[0006]
Furthermore, since it is difficult to efficiently form a thick conductive layer by the vapor deposition method as described above, the thickness of the conductive layer is inevitably reduced, and also from this point, a reliable electrical connection is guaranteed. I couldn't.
[0007]
On the other hand, in order to increase the reliability of the electrical connection, on the other hand, the conductive layer is further thickened by electroplating on the conductive layer by vapor deposition in the through hole or on the underlying layer by electroless plating or carbon treatment. Attempts have been made to form layers. That is, by first forming a conductive layer by bonding copper foil or the like on both the front and back sides of an insulating substrate with an adhesive, and then opening the holes by known punching such as punching, drilling, pressing, or laser. A through hole is formed so as to penetrate both the insulating substrate and the conductive layer. After that, a method of forming a conductive layer, an electroless plating method or a base layer by a carbon treatment method by an evaporation method, and further laminating a conductive layer on the wall surface of the through hole by an electroplating method has been attempted.
[0008]
However, in this method as well, since copper foil or the like is bonded to the insulating substrate via an adhesive, the same problem as described above occurs, and the conductive layers (copper foil and the like) on both the front and back surfaces of the insulating substrate and the through holes Since the configuration of the conductive layer (plating layer or the like) is completely different and lacks in unity, reliable electrical connection could not be guaranteed. In addition, since both the conductive layers are manufactured through completely independent manufacturing processes as described above, the production efficiency is deteriorated.
[0009]
On the other hand, a conductive sheet in which an aluminum foil is bonded instead of a copper foil bonded to an insulating substrate as a conductive layer is also known, but the same adhesive as described above is used for the bonding. In this case, the same problems as described above were observed. Furthermore, the aluminum foil present on the front and back of the insulating substrate is electrically connected by caulking or ultrasonic fusion, but the reliability of the aluminum foil itself is covered by the fact that the surface of the aluminum foil is covered with oxide. A highly efficient electrical connection effect could not be obtained.
[0010]
[Patent Document 1]
JP-A-4-286394
[0011]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described present situation, and the object of the present invention is to have highly reliable electrical connectivity, good circuit pattern formation, and good production efficiency. Another object is to provide a conductive sheet for a non-contact type IC card with a built-in antenna and a non-contact type IC card with a built-in antenna using the same.
[0012]
[Means for Solving the Problems]
The conductive sheet for a non-contact IC card with a built-in antenna of the present invention has conductive layers formed on both front and back surfaces of an insulating substrate, and the conductive layers on both surfaces are opened so as to penetrate the insulating substrate. A conductive sheet electrically connected to each other through a through hole or a via hole, wherein the conductive layer is formed directly on the insulating substrate, and the wall surface of the through hole or the inside of the via hole And the both sides of the insulating substrate have the same configuration, and the conductive layer constitutes a circuit including an antenna.
[0013]
The conductive layer is preferably formed in the same process on the wall surface of the through hole or the inside of the via hole and on both the front and back surfaces of the insulating substrate, and a circuit including an antenna can be formed by etching. it can.
[0014]
The conductive layer may include a first conductive layer formed by a sputtering method or an evaporation method and a second conductive layer formed by an electroless plating method or an electroplating method.
[0015]
Further, after a portion on the first conductive layer is masked with a resist, the second conductive layer is formed on a portion not masked with the resist, whereby a circuit including an antenna can be formed.
[0016]
Further, a connection layer having a thickness of 0.2 to 15 μm is formed on the surface of the conductive layer by at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn, and Cr, or an alloy containing at least one metal. Can be formed.
[0017]
Further, the surface of the conductive layer is prevented from being oxidized with a thickness of 0.01 to 2 μm by at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn and Cr or an alloy containing at least one metal. A layer can be formed.
[0018]
The non-contact IC card with a built-in antenna of the present invention uses the conductive sheet for the non-contact IC card with a built-in antenna.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
<Conductive sheet for non-contact IC card with built-in antenna>
The conductive sheet for a non-contact IC card with a built-in antenna of the present invention has conductive layers formed on both front and back surfaces of an insulating substrate, and the conductive layers on both surfaces are opened so as to penetrate the insulating substrate. A basic configuration is a configuration in which they are electrically connected to each other through through holes or via holes.
[0020]
More specifically, as shown in FIGS. 1 and 2, the conductive sheet 1 for a contactless IC card with a built-in antenna according to the present invention has conductive layers 3 formed on both front and back surfaces of an insulating substrate 2. The conductive layer 3 constitutes a circuit including the antenna 4 and is electrically connected to both the front and back surfaces through a through hole or a via hole 5. The conductive layer 3 is also electrically connected to the IC chip 6.
[0021]
Here, the antenna is mainly in the form of a coil (spiral), and has the function of receiving and supplying signals, power supplies, clocks and the like in a non-contact state with respect to external devices. Hereinafter, each configuration of the conductive sheet for the non-contact IC card with a built-in antenna according to the present invention will be described in more detail. In the description of the present application using the drawings, the same reference numerals given in the drawings represent the same or corresponding portions.
[0022]
<Insulating substrate>
As the insulating base used as the base of the conductive sheet for the non-contact type IC card with a built-in antenna of the present invention, any conventionally known base that can be used for this kind of application is used without any limitation. be able to. In particular, a film having a thin thickness is preferable. This is because it is suitable for forming a conductive layer described later, and can be processed as a long continuous material such as a roll, thereby improving production efficiency.
[0023]
Examples of such an insulating substrate include, for example, polyesters such as polyimide, aramid, and PET, polysulfone, polyetherimide, polyphenylene oxide, PEN, liquid crystal polymer, glass fiber reinforced epoxy resin, phenol resin, and acrylic resin. A film can be mentioned. Among these, it is particularly preferable to use a film made of polyimide, PET, or glass fiber reinforced epoxy resin that has excellent flexibility and high performance.
[0024]
In addition, the film here has a thickness of 4 to 150 μm, preferably about 25 to 50 μm. If it is less than 4 μm, the strength may be weak and it may not be able to withstand processing, and if it exceeds 150 μm, it may not be flexible and cannot be handled. This is because it may hinder the formation of the conductive layer.
[0025]
In addition, the shape of the insulating substrate is particularly suitable for the shape of the insulating substrate as described above. However, if the shape is a film shape, even if it is in the form of a single wafer, it is a long continuous shape like a roll. It may be in the form. In the present invention, it is particularly preferable to use a long continuous material such as a roll from the viewpoint of processing efficiency in production.
[0026]
<Through hole>
The through-hole in the present invention is a small hole provided so as to physically penetrate the front and back of the insulating substrate, and the conductive material described later is formed on both the front and back surfaces of the insulating substrate through the through-hole. The layers will be electrically connected to each other.
[0027]
In the present invention, it is preferable to form a conductive layer, which will be described later, after forming this through hole on the insulating substrate. As a result, the conductive layers on both sides of the insulating substrate and the conductive layer in the through hole can be integrally formed, which can contribute to the improvement of production efficiency and guarantee a highly reliable electrical connection. can do.
[0028]
The shape of such a through hole is not particularly limited as long as it penetrates the front and back of the insulating substrate. For example, the cross-sectional shape thereof can be circular or polygonal. When the shape is circular, the inner diameter is 5 μm to 3 mm, preferably 25 to 300 μm. When the inner diameter is less than 5 μm, it is difficult to open the hole and the processing cost is increased, and when it exceeds 3 mm, the area of the through hole on the entire surface of the insulating substrate becomes too large to secure an effective circuit space.
[0029]
Further, the hole density (number) of such through holes is not particularly limited, but is usually 100 cm. ² The number is 10 to 10 million per unit, more generally 100 to 500,000, and more generally 100 to 100,000. If the number is less than 10, the substantial function of electrically connecting the conductive layers on the front and back of the conductive sheet through the through hole is not shown, and if the number exceeds 10 million, the strength of the insulating substrate can be maintained for processing. It is not preferable because the accuracy is lost.
[0030]
Such a through hole can be formed by any method without particular limitation as long as it is a conventionally known opening method (drilling method). For example, CO ₂ Opening is performed by penetrating the insulating substrate by various opening means such as various lasers such as lasers, drills, punches and presses. In particular, when the through hole has an inner diameter of less than 80 μm, it is preferable to open the holes with various lasers.
[0031]
<Beer Hall>
The via hole in the present invention is a small hole provided so as to physically penetrate the front and back surfaces of the insulating substrate, and the conductive material described later is formed on both the front and back surfaces of the insulating substrate through the via hole. The layers will be electrically connected to each other. In this way, the via hole has the same function as the through hole. However, the via hole has a form in which a conductive layer is formed only on the wall surface and a hollow portion remains in the central portion. Is different in that the inside of the hole is completely filled with a conductive layer and does not have a hollow portion.
[0032]
Whether the conductive layers on the front and back surfaces of the insulating substrate are electrically connected via through holes or via holes is determined depending on the shape of the circuit pattern including the antenna, the size of the integrated circuit, etc. These two can be formed singly or in combination.
[0033]
In the present invention, it is preferable to form a conductive layer described later after forming the via hole in the insulating substrate. As a result, the conductive layers on both sides of the insulating substrate and the conductive layers filled in the via holes can be integrally formed, which can contribute to improvement of production efficiency and highly reliable electrical Connection can be guaranteed.
[0034]
The shape of such a via hole is not particularly limited as long as it penetrates the front and back surfaces of the insulating substrate. For example, the cross-sectional shape can be circular or polygonal. When the shape is circular, the inner diameter is 5 to 100 μm, preferably 10 to 25 μm. When the inner diameter is less than 5 μm, it is difficult to open the hole and the processing cost is increased, and when it exceeds 100 μm, it takes a long time to fill the inside of the hole with the conductive layer, thereby deteriorating the production efficiency.
[0035]
Further, the opening density (number) of such via holes is not particularly limited, but is usually 100 cm. ² The number is 10 to 10 million per unit, more generally 100 to 500,000, and more generally 100 to 100,000. If the number is less than 10, the substantial function of electrically connecting the conductive layers on the front and back sides of the conductive sheet through via holes is not shown, and if the number exceeds 10 million, the strength of the insulating substrate can be maintained for processing. It is not preferable because the accuracy is lost.
[0036]
Such a via hole can be opened by any method without particular limitation as long as it is a conventionally known opening method (drilling method). For example, CO ₂ A hole is formed by penetrating the insulating substrate by various lasers such as a laser, a YAG laser, and an excimer laser.
[0037]
<Conductive layer>
The conductive layer of the present invention is formed on both the front and back surfaces of the insulating substrate, is also formed on the wall surface of the through hole, and is formed so as to fill the inside of the via hole. Such a conductive layer is formed directly on the insulating substrate, and is formed so as to have the same configuration on the wall surface of the through hole or the inside of the via hole and on both the front and back surfaces of the insulating substrate.
[0038]
Here, that the conductive layer is directly formed on the insulating substrate means that the conductive layer is formed so as to be in direct contact with the insulating substrate without using an adhesive or the like, and only the front and back surfaces of the insulating substrate are formed. Instead, the through holes and via holes are formed so as to be in direct contact with the insulating substrate. As a result, the inventors have successfully solved various problems that have been caused by the use of conventional adhesives.
[0039]
The conductive layers on both the front and back surfaces of such an insulating substrate are electrically connected to each other through a through hole or a via hole. Means that the conductive layers formed on both the front and back surfaces of the insulating base are electrically connected by the conductive layers having the same configuration formed on the wall surface of the through hole. In addition, being electrically connected through a via hole means that the conductive layers formed on both the front and back surfaces of the insulating base are electrically connected by a conductive layer having the same configuration filled in the via hole. It means that In this way, a highly reliable electrical connection is possible because the conductive layer on the wall surface of the through hole or the conductive layer filled in the via hole and the conductive layer on both the front and back surfaces of the insulating substrate have the same configuration. It becomes.
[0040]
The composition of such a conductive layer is not particularly limited as long as it has an electrical conductivity effect, but it is from the group consisting of Cu, Ni, Cr, Ag, Au, Zn, Ti, Pd, Sn, and Co. It is preferably composed of at least one selected metal or an alloy containing at least one of the above metals, and can be formed as a single layer and formed by laminating a plurality of layers having the same composition or different compositions. You can also
[0041]
That the conductive layer has the same configuration in the wall surface of the through hole or the via hole and both the front and back surfaces of the insulating substrate means that the stacked state is the same, and the thickness of the layer is not necessarily the same. But it doesn't mean that they are the same.
[0042]
The conductive layer constitutes a circuit including an antenna, and the antenna is built in the non-contact type IC card. As a method for forming a circuit including such an antenna, an etching method or an additive method described later is preferably used.
[0043]
Moreover, it is preferable that the said conductive layer is formed in the same process in the wall surface of the said through hole or the inside of the said via hole, and the front and back both surfaces of the said insulating base | substrate. Note that a method of forming in the same process will be described later.
[0044]
Such a conductive layer can include a first conductive layer formed by a sputtering method or an evaporation method and a second conductive layer formed by an electroless plating method or an electroplating method. In the present invention, each of the first conductive layer and the second conductive layer may be laminated as a single layer or a plurality of layers to constitute a conductive layer.
[0045]
<First conductive layer>
The first conductive layer of the present invention is formed directly on the insulating substrate, and is preferably a metal or an alloy containing at least one of the above metals, more preferably Cu, Ni, Cr, Co, Ti or At least one metal selected from Zn or an alloy containing at least one metal can be formed by sputtering or vapor deposition. This first conductive layer has a function as a so-called underlayer for forming a second conductive layer to be described later, and has a function of improving the adhesion of the second conductive layer to the insulating substrate. .
[0046]
Such a first conductive layer is preferably formed with a thickness of 500 to 5000 mm, preferably 1000 to 3000 mm. If it is less than 500 mm, the effect of improving the adhesion of the second conductive layer, which will be described later, cannot be sufficiently exhibited, and if it exceeds 5000 mm, the adhesion of the second conductive layer is not greatly different, and it is disadvantageous in terms of cost.
[0047]
Such a first conductive layer can be formed by laminating one layer (single layer) or two or more layers (multiple layers) as described above. When two or more layers are laminated, the first conductive layer has the above thickness as a whole. It can be.
[0048]
When two or more layers of the first conductive layer are laminated, a metal such as Ni, Cr, Ti or an alloy containing the metal is first laminated on the insulating substrate, and a metal such as Cu or the metal is laminated thereon. It is preferable to laminate an alloy containing A metal such as Cu is advantageous for use in such applications because it has good electrical characteristics, is excellent in adhesion to the second conductive layer, and is relatively inexpensive. In addition, there is a problem that the electrical characteristics are impaired. Therefore, in order to solve this problem of oxidation, a metal having oxidation resistance, for example, a metal such as Ni, Cr, Ti, etc., is formed under such a metal layer such as Cu (that is, between the insulating base). If the layer is formed, it is possible to prevent deterioration of the adhesion force over time due to oxidation.
[0049]
Such a layer made of a metal having oxidation resistance has a thickness of 10 to 200 mm, preferably 30 to 70 mm. If the thickness is less than 10 mm, the oxidation resistance may not be sufficient, and if it exceeds 200 mm, etching may be difficult when forming a circuit pattern.
[0050]
<Second conductive layer>
The second conductive layer of the present invention is formed on the first conductive layer, and is at least one selected from the metals shown above or an alloy containing at least one of the metals, more preferably Cu, Ag or Zn. This metal or an alloy containing at least one of the metals is applied by an electroless plating method or an electroplating method. By forming the second conductive layer to be thicker than the first conductive layer, the second conductive layer mainly has an effect of imparting electrical conductivity and contributes to conduction of a circuit including the antenna. In addition, since the second conductive layer exhibits electrical conductivity, if it is disposed so as to face both the front and back surfaces of the insulating substrate, it can also function as a capacitor.
[0051]
Such a second conductive layer is preferably formed with a thickness of 1 to 100 μm, preferably 5 to 40 μm. If the thickness is less than 1 μm, there is a problem that sufficient electric conductivity cannot be obtained and the electric resistance becomes too large, and if it exceeds 100 μm, there is no great difference in electric conductivity, which is disadvantageous in cost.
[0052]
Such a second conductive layer can be formed by laminating one layer (single layer) or two or more layers (multiple layers) as described above. When two or more layers are laminated, the second conductive layer has the above thickness as a whole. It can be.
[0053]
The second conductive layer is preferably formed by employing an electroplating method when formed to be relatively thick, and is formed by employing an electroless plating method when formed to be relatively thin. It is preferable.
[0054]
<Method for forming conductive layer>
The conductive layer of the present invention is formed in the same process on both the front and back surfaces of the insulating substrate and the wall surface of the through hole or the inside of the via hole after through holes or via holes are formed in the insulating substrate. It is preferable. As a result, it is possible to integrally form the conductive layers on both sides of the insulating substrate and the wall surface in the through hole or the conductive layer in the via hole, which can contribute to improvement of production efficiency and reliability. High electrical connection can be guaranteed. It also contributes to improvement of dimensional accuracy.
[0055]
Here, the conductive layer is formed in the same process means that the conductive layer is formed simultaneously and integrally on both the front and back surfaces of the insulating substrate and the wall surface of the through hole or the inside of the via hole. I mean.
[0056]
That is, for example, when the conductive layer includes a first conductive layer and a second conductive layer, the first conductive layer is first sputtered onto both the front and back surfaces of the insulating substrate and the wall surface of the through hole or the inside of the via hole. Alternatively, when the second conductive layer is formed simultaneously and integrally by vapor deposition, and then the second conductive layer is formed simultaneously and integrally on the first conductive layer by electroless plating or electroplating. Is included. When the inside of the via hole is filled with the conductive layer simultaneously and integrally with both the front and back surfaces of the insulating substrate, the first conductive layer is mainly formed on the wall surface of the via hole and formed on the first conductive layer. The inside of the hole is filled with the second conductive layer, and the cavity is filled.
[0057]
As described above, when the conductive layer includes the first conductive layer and the second conductive layer, or when each layer is stacked in plural layers, as long as each layer is formed simultaneously and integrally as described above. The conductive layer is formed in the same process.
[0058]
In the case where the conductive layer is formed by sputtering or vapor deposition, and the front and back surfaces of the insulating substrate cannot be processed at a time due to the characteristics of the processing apparatus, etc., each of the front and back surfaces is performed twice. Even if the conductive layer is formed by the above operation, the conductive layers on both the front and back surfaces and the conductive layer inside the through-hole wall or the via hole are formed in the same process. In this case, it is considered that the wall of the through hole or the conductive layer inside the via hole is formed up to the middle height (depth) of the hole by each of these two operations. Thus, it is considered that the conductive layer is formed on the entire wall surface of the through hole or the inside of the via hole. Further, even if the conductive layer is weightedly stacked in the middle height (depth) portion of the hole, the configuration of the portion is the same as the configuration of the conductive layer on the surface portion of the insulating substrate. Shall be deemed.
[0059]
By forming the conductive layer in the same process in this manner, conventionally, after first forming the conductive layer on both the front and back surfaces of the insulating substrate, a through hole or a via hole is opened, and then the wall surface of the through hole or the inside of the via hole is again formed. Compared with the method in which the conductive layer is formed, the number of steps of forming the conductive layer can be halved, so that the production efficiency can be greatly improved. And since it forms integrally in the same process, a highly reliable connection effect is acquired.
[0060]
Further, in the conventional method as described above, it is difficult to selectively form the conductive layer only on the wall surface of the through hole or the inside of the via hole, and the conductive layer formed on the insulating substrate is inevitably formed. The conductive layer is formed so as to wrap around to the top. However, in this case, the thickness of the conductive layer is formed by weighting, and when the thickness of the conductive layer on the insulating substrate is increased as described above, it is difficult to form a circuit and the dimensional accuracy itself deteriorates. On the other hand, according to the above-described formation method of the present invention, the thickness of the conductive layer is not weighted, and thus the thickness of the conductive layer can be reduced as much as possible, thereby easily forming a circuit. And dimensional accuracy is not deteriorated.
[0061]
<Method for forming a circuit or the like using a conductive layer>
The conductive layer of the present invention constitutes a circuit including an antenna, and the circuit forming method is preferably according to the following method. Hereinafter, description will be given based on FIG. 3 and FIG.
[0062]
First, the first conductive layer 3a and the second conductive layer 3b are formed on the insulating substrate 2 having the through holes 5a as described above (FIGS. 3A to 3C). Subsequently, a resist 7 is applied to the entire surface of the conductive layer 3 (including the first conductive layer 3a and the second conductive layer 3b) (including the case where a dry film is laminated; the same applies hereinafter) (FIG. 3D )) After being overlaid with a mask 8 representing a desired circuit pattern, exposure is performed (FIG. 3E). In the figure, a mode in which a white portion of the mask 8 is exposed is shown.
[0063]
Next, the resist is removed from the portion 9 where the circuit is not formed by developing (the portion not exposed above) (FIG. 3F), and the conductive layer in the portion where the resist is removed is removed by etching (FIG. 3). 3 (g)). Then, by removing the resist remaining on the conductive layer that has not been etched, the circuit 10 is formed by the conductive layer 3 (FIG. 3H). As described above, the conductive layer 3 forms a circuit including an antenna by etching.
[0064]
In the above description, the through hole 5a has been described as an example, but the same applies to the case of a via hole. Further, although the resist 7 is applied to the entire surface of the conductive layer 3, the resist 7 can be printed and applied so as to represent a desired circuit pattern instead of this method. In this case, exposure and development processing using the above-described mask 8 are not necessary.
[0065]
On the other hand, a circuit using a conductive layer can be formed by a method different from the above. That is, the first conductive layer 3a is formed on the insulating substrate 2 having the through hole 5a (FIGS. 4A to 4B). Subsequently, a resist 7 is applied on the first conductive layer 3a (FIG. 4C), and is overlaid with a mask 8 representing a desired circuit pattern, and then exposed (FIG. 4D). In the figure, a mode in which a white portion of the mask 8 is exposed is shown.
[0066]
Next, development is performed to remove the resist in the portion 11 (the portion not exposed above) that forms the circuit (FIG. 4E), and the second conductive layer 3b is formed in the portion from which the resist has been removed (see FIG. 4E). FIG. 4 (f)). Then, after the resist remaining on the portion where the second conductive layer 3b is not formed is peeled off (FIG. 4G), the portion of the first conductive layer 3a where the resist is peeled off is soft-etched. A circuit 10 made of the conductive layer 3 is formed (FIG. 4H). As described above, after the portion on the first conductive layer is masked with the resist, the second conductive layer is formed on the portion not masked with the resist, thereby forming the circuit including the antenna. (The above method is called the additive method).
[0067]
In the above description, the through hole 5a has been described as an example, but the same applies to the case of a via hole. Moreover, although the resist 7 is apply | coated to the whole surface of the 1st conductive layer 3a, it can replace with this method and can apply | coat the resist 7 so that a desired circuit pattern may be represented. In this case, exposure and development processing using the above-described mask 8 are not necessary.
[0068]
<Connection layer>
A connection layer can be further formed on the conductive layer of the present invention. The connection layer has an effect of facilitating mounting of an integrated circuit (IC chip or LSI) on an insulating substrate, and directly connects the conductive layer and the integrated circuit.
[0069]
Such a connection layer is preferably composed of at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn and Cr, or an alloy containing at least one of the above metals. Moreover, the thickness is 0.2-15 micrometers, Preferably it is 0.5-5 micrometers. If the thickness is less than 0.2 μm, the effect of facilitating the mounting of the integrated circuit is not shown, and if it exceeds 15 μm, the effect of facilitating the mounting of the integrated circuit is not greatly different, and the cost increases.
[0070]
Such a connection layer can be formed as a single layer or a plurality of layers on the entire surface of the conductive layer or a portion like a bump by any one of an electroless plating method, an electroplating method, and a chromate method.
[0071]
<Antioxidation layer>
An antioxidant layer can also be formed on the conductive layer of the present invention. The anti-oxidation layer has a function of preventing the conductive layer from being oxidized so that the conductivity is not exhibited, or the adhesion with the insulating substrate is deteriorated.
[0072]
Such an antioxidant connection layer is preferably composed of at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn and Cr, or an alloy containing at least one of the above metals. Moreover, the thickness is 0.01-2 micrometers, Preferably it is 0.05-1 micrometer. When the thickness is less than 0.01 μm, the above-described effects are not exhibited, and when the thickness exceeds 2 μm, the above-described effects are not significantly different, and the cost increases.
[0073]
Such an antioxidant layer can be formed as a single layer or a plurality of layers on the entire surface or part of the conductive layer by any one of electroless plating, electroplating, or chromate.
[0074]
In addition, since such an antioxidant layer and the connection layer can be made of substantially the same material, both of them are formed on the conductive layer simultaneously and integrally by adjusting only the thickness thereof. can do. That is, a layer having a thickness of 0.01 to 2 μm is formed on the entire surface of the conductive layer as an anti-oxidation layer, and only a portion corresponding to the mounting portion of the integrated circuit (a portion serving as a bump) has a thickness of 0.2 to It can be formed as a connection layer having a thickness of 15 μm.
[0075]
<Non-contact IC card with built-in antenna>
The non-contact IC card with a built-in antenna of the present invention uses the conductive sheet described above, and an integrated circuit (IC chip or LSI) is mounted on the conductive sheet, and finally these are made of resin. It can be made into a form that is sealed or sandwiched between synthetic resin films.
[0076]
Such a contactless IC card with a built-in antenna can be used for various ID cards, telephone cards, traffic cards (having both functions of boarding pass and prepaid card), electronic money, and the like.
[0077]
<Others>
An alignment mark can be formed on the insulating substrate of the present invention. The alignment mark serves as a reference for determining a predetermined position of the through hole or the via hole, and is usually preferably formed at both ends (positions where no through hole is provided) of the insulating substrate.
[0078]
Any alignment mark may be used as long as it can determine a predetermined position of a through hole or a via hole by optical, electronic, magnetic, visual, or other reading means. However, it is not particularly limited. For example, in the case of visual reading, it is preferable that the alignment mark has a hole opened through both ends of the insulating substrate. The holes (referred to as alignment holes) are more preferably opened continuously with a constant interval. This is because the positions of through holes and via holes can be determined more easily by adopting such a configuration.
[0079]
The size of such an alignment hole is usually about 20 μm to 3 mm, preferably 50 μm to 2 mm. If it is less than 20 μm, the positioning accuracy is good, but expensive processing equipment is required. If it exceeds 3 mm, good positioning accuracy cannot be obtained.
[0080]
Such an alignment hole can be opened by, for example, various lasers, drills, punches, presses, and the like. In particular, when the size is smaller than 80 μm, it is preferable to use various lasers.
[0081]
Further, such an alignment hole may have a conductive layer formed on its inner wall surface, similar to the above-mentioned through hole.
[0082]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.
[0083]
<Example 1>
First, as an insulating substrate, a PET film (trade name: Emplet, manufactured by Unitika Co., Ltd.) slit to a thickness of 50 μm, a width of 250 mm, and a length of 100 m is wound around a synthetic resin core, and then CO ₂ It was set on a laser processing machine (Mitsubishi Electric). Then, with this processing machine, a through hole having an inner diameter of 100 μm and an alignment hole having an inner diameter of 1.0 mm were opened so as to penetrate both the front and back surfaces of the PET film.
[0084]
Subsequently, the PET film was set in a pure water cleaning apparatus, and 2 kg / cm. ² The surface of the PET film was cleaned on both sides by showering at a water pressure of. Then, it drained with the dry air of 105 degreeC which passed the high performance filter (The magnitude | size of the aperture part of a filter is 0.5 micrometer or less), and made it fully dry.
[0085]
Next, one end of the insulating substrate cleaned in this way was set on the delivery shaft of the sputtering apparatus, and the other end was set on the winding shaft. On the other hand, the target No. 1 and Ni / Cr alloy (Ni / Cr = 80/20). Cu was attached as 2-4, respectively.
[0086]
Then, the chamber of the sputtering apparatus is closed, and the degree of vacuum is set to 1 × 10 using a vacuum pump. ^-4 After setting to Pa, the target No. with the Ni / Cr alloy attached was set. 1, the argon gas injection rate is 100 cc / min, and the target current is 0.3 A / dm. ² , And a target No. attached with Cu. For 2-4, argon gas injection rate 200cc / min each, target current 0.9A / dm ² The first conductive layer was formed on one surface of the insulating substrate by sputtering these metals under the conditions described above. Thereafter, the vacuum state of the sputtering apparatus was released.
[0087]
Subsequently, the insulating base is turned upside down again so that a first conductive layer similar to the above can be formed on the surface of the insulating base on which the first conductive layer is not formed. It was set in the sputtering apparatus again. Then, the same first conductive layer as described above was formed on the other surface of the insulating substrate by performing sputtering under the same conditions as described above.
[0088]
As a result, the first conductive layer could be directly formed on both the front and back surfaces of the insulating substrate and the wall surface of the through hole (and the wall surface of the alignment hole) (see FIG. 3B). Although not shown in FIG. 3B, the first conductive layer has a structure in which a Ni / Cr alloy layer is first laminated on an insulating substrate and a Cu layer is laminated thereon. And this structure is the same structure in the front and back both surfaces on an insulating base | substrate, and the wall surface of a through hole.
[0089]
In addition, sampling was performed at points 10 m, 50 m, and 90 m from one end of the insulating base, and the cross-section was cut using a FIB apparatus and the thickness thereof was measured. Thus, it was confirmed that the Ni / Cr alloy layer was 60 mm, the Cu layer was 2900 mm, and the wall thickness of the through hole was the same.
[0090]
Subsequently, after washing with pure water several times, the insulating substrate having the first conductive layer formed on both the front and back surfaces as described above was set in a continuous plating apparatus and electroplated under the following conditions. . That is, first, the first conductive layer is subjected to an acid activation treatment by continuously immersing the insulating substrate in an acid activation tank (30 ° C.) filled with 7% sulfuric acid for 60 seconds. It was.
[0091]
Subsequently, washing with pure water was repeated three times, and then the plating solution (copper sulfate 110 g / l, sulfuric acid 160 g / l, chlorine 60 ppm and Top Lucina 380H (Okuno Pharmaceutical Co., Ltd.) 10 cc / l was added to the plating bath of the above apparatus. And the above-mentioned insulating substrate is continuously dipped at a moving speed of 1.0 m / min, a liquid temperature of 30 ° C., and a current density of 4 A / dm. ² A second conductive layer made of Cu was formed on the first conductive layer by electroplating for 11 minutes under the above conditions.
[0092]
Thereby, the first conductive layer was formed on both the front and back surfaces of the insulating base and the wall surface of the through hole (and the wall surface of the alignment hole), and the second conductive layer could be formed on the first conductive layer ( (See FIG. 3 (c)). The second conductive layer has the same configuration on both the front and back surfaces of the insulating substrate and the wall surface of the through hole. Therefore, the conductive layer includes the first conductive layer and the second conductive layer, and the conductive layer having the same configuration is formed on both the front and back surfaces of the insulating base and the wall surface of the through hole.
[0093]
Subsequently, the insulating substrate on which the second conductive layer was thus formed was repeatedly washed with pure water five times. Next, draining was performed with 105 ° C. dry air that passed through a high-performance filter (the aperture size of the filter was 0.5 μm or less), and the film was sufficiently dried. Thereafter, sampling is performed at points 10 m, 50 m, and 90 m from one end of the insulating substrate on which the second conductive layer is formed in this way, and the cross section is cut using a FIB apparatus to measure the thickness of the second conductive layer. As a result, it was 10.2 μm on both the front and back surfaces of the insulating substrate at each point, and 10.0 μm on the wall surface of the through hole.
[0094]
Next, a dry film (trade name: NIT215, manufactured by Nichigo Morton) is applied as a resist over the entire surface of the second conductive layer of the insulating base, at a temperature of 110 ° C. and a pressure of 2.5 kg / cm. ² By laminating under the above conditions, a resist was formed on the second conductive layer (see FIG. 3D).
[0095]
Next, a mask showing a desired circuit pattern on both the front and back surfaces of the insulating substrate was overlaid on the resist, and then exposed with a light amount of 120 mJ using an average exposure machine (manufactured in-house) (FIG. 3 (e )reference). Subsequently, in order to remove the resist in the portion where the circuit is not formed, sodium carbonate 1 g / l, temperature 30 ° C., spray pressure 1.5 kg / cm using a developing device. ² The resist was removed by developing under the conditions (see FIG. 3F).
[0096]
Next, in order to remove the conductive layer (including the first conductive layer and the second conductive layer) from which the resist has been removed, ferric chloride 47%, temperature 48 ° C., spray pressure 2.5 kg / cm ² The conductive layer was removed by etching under the conditions (see FIG. 3G).
[0097]
Then, in order to remove the resist on the conductive layer which has not been etched, caustic soda 100 g / l, temperature 60 ° C., spray pressure 2.0 kg / cm using a resist peeling apparatus. ² By stripping the resist under the above conditions, a conductive sheet for a non-contact type IC card with a built-in antenna of the present invention was obtained (see FIG. 3 (h)).
[0098]
In addition, the electroless Sn plating solution (trade name: Substar Sn, manufactured by Okuno Pharmaceutical Co., Ltd.) is used on the conductive layer (second conductive layer) on which the above circuit is formed at a temperature of 28 ° C. An anti-oxidation layer made of Sn was formed by performing electroless plating. When the thickness of the antioxidant layer was measured using a fluorescent X-ray film thickness meter (trade name: # 3200, manufactured by Seiko), the thickness of the antioxidant layer was 0.09 μm.
[0099]
The conductive sheet for the non-contact type IC card with a built-in antenna thus obtained has a part of the circuit formed by the conductive layer as a coiled antenna, and there is no problem with the electrical conductivity on both the front and back sides. In addition, it showed highly reliable electrical connectivity, good circuit pattern formability and good production efficiency.
[0100]
<Example 2>
The insulating base on which the first conductive layer was formed was obtained in the same manner as in Example 1 until the first conductive layer was formed on both the front and back surfaces of the insulating base.
[0101]
The insulating substrate thus obtained is immersed in an immersion bath of a 100 cc / l palladium catalyst (trade name: Accelerator, manufactured by Okuno Pharmaceutical Co., Ltd.) for 1 minute at room temperature, thereby the first conductive layer. Catalyst treatment was applied to the top.
[0102]
Subsequently, after washing with pure water five times, the electroless copper plating solution for through-holes (trade name: OPC-750 electroless copper M (trade name), Okuno on the first conductive layer treated with the catalyst. A second conductive layer made of copper and having a thickness of 1 μm was formed by performing electroless plating treatment at room temperature and pH 12.9 using a pharmaceutical industry).
[0103]
Next, the insulating substrate on which the second conductive layer was formed in this manner was repeatedly washed with pure water five times. Thereafter, the first conductive layer and the first conductive layer are formed on the insulating substrate by draining with 105 ° C. dry air that has passed through a high-performance filter (the aperture size of the filter is 0.5 μm or less) and sufficiently drying. A conductive layer including the second conductive layer was formed.
[0104]
Thereafter, a circuit was formed in the same manner as in Example 1, and an antioxidant layer was formed on the conductive layer.
[0105]
The conductive sheet for the non-contact IC card with a built-in antenna thus obtained exhibits highly reliable electrical connectivity, excellent circuit pattern formability, and excellent production efficiency. It was.
[0106]
<Example 3>
First, as an insulating substrate, a PET film (trade name: Emplet, manufactured by Unitika Co., Ltd.) slit to a thickness of 25 μm, a width of 250 mm, and a length of 100 m is wound around a synthetic resin core, and then a YAG laser processing machine. (Mitsubishi Electric). And with this processing machine, a via hole with an inner diameter of 25 μm and an alignment hole with an inner diameter of 1.0 mm were respectively opened so as to penetrate both the front and back surfaces of the PET film.
[0107]
Subsequently, the PET film was set in a pure water cleaning apparatus, and 2 kg / cm. ² The surface of the PET film was cleaned on both sides by showering at a water pressure of. Then, it drained with the dry air of 105 degreeC which passed the high performance filter (The magnitude | size of the aperture part of a filter is 0.5 micrometer or less), and made it fully dry.
[0108]
Next, one end of the insulating substrate cleaned in this way was set on the delivery shaft of the sputtering apparatus, and the other end was set on the winding shaft. On the other hand, the target No. 1 and Ni / Cr alloy (Ni / Cr = 80/20). Cu was attached as 2-4, respectively.
[0109]
Then, the chamber of the sputtering apparatus is closed, and the degree of vacuum is set to 1 × 10 using a vacuum pump. ^-4 After setting to Pa, the target No. with the Ni / Cr alloy attached was set. 1, the argon gas injection rate is 100 cc / min, and the target current is 0.3 A / dm. ² , And a target No. attached with Cu. For 2-4, argon gas injection rate 200cc / min each, target current 0.9A / dm ² The first conductive layer was formed on one surface of the insulating substrate by sputtering these metals under the conditions described above. Thereafter, the vacuum state of the sputtering apparatus was released.
[0110]
Subsequently, the insulating base is turned upside down again so that a first conductive layer similar to the above can be formed on the surface of the insulating base on which the first conductive layer is not formed. It was set in the sputtering apparatus again. Then, the same first conductive layer as described above was formed on the other surface of the insulating substrate by performing sputtering under the same conditions as described above.
[0111]
As a result, the first conductive layer could be directly formed on both the front and back surfaces of the insulating substrate and the wall surface of the via hole (and the wall surface of the alignment hole) (see FIG. 4B). Although not shown in FIG. 4B, the first conductive layer has a configuration in which a Ni / Cr alloy layer is first laminated on an insulating substrate and a Cu layer is laminated thereon. And this structure is the same structure in the front and back both surfaces on an insulating base | substrate, and the wall surface of a via hole.
[0112]
In addition, sampling was performed at points 10 m, 50 m, and 90 m from one end of the insulating base, and the cross-section was cut using a FIB apparatus and the thickness thereof was measured. Thus, the Ni / Cr alloy layer was 50 mm, the Cu layer was 2500 mm, and the wall thickness of the via hole was confirmed to be the same thickness.
[0113]
Thereafter, after cleaning with pure water several times, a resist was printed and applied so as to form a desired circuit pattern on the first conductive layer (see FIG. 4E).
[0114]
Subsequently, after cleaning with pure water several times, the insulating substrate on which the resist was printed and applied on both the front and back surfaces was set in a continuous plating apparatus, and electroplating was performed under the following conditions. That is, first, the first conductive layer is subjected to an acid activation treatment by continuously immersing the insulating substrate in an acid activation tank (30 ° C.) filled with 7% sulfuric acid for 60 seconds. It was.
[0115]
Subsequently, washing with pure water was repeated three times, and then the plating solution (copper sulfate 110 g / l, sulfuric acid 160 g / l, chlorine 60 ppm and Top Lucina 380H (Okuno Pharmaceutical Co., Ltd.) 10 cc / l was added to the plating bath of the above apparatus. And the above-mentioned insulating substrate is continuously dipped at a moving speed of 1.0 m / min, a liquid temperature of 30 ° C., and a current density of 4 A / dm. ² The second conductive layer made of Cu was formed on the portion where the resist on the first conductive layer was not formed by electroplating for 15 minutes under the above conditions.
[0116]
As a result, the first conductive layer is formed on both the front and back surfaces of the insulating base and the wall surface of the via hole (and the wall surface of the alignment hole), and the second conductive layer is formed on the portion where the resist on the first conductive layer is not formed. (See FIG. 4 (f), however, the configuration of the hole portion is different). The configuration of the second conductive layer is the same on both the front and back surfaces of the insulating substrate and the inside of the via hole. Therefore, the conductive layer includes the first conductive layer and the second conductive layer, and the conductive layer having the same configuration is formed on both the front and back surfaces of the insulating base and the inside of the via hole.
[0117]
Subsequently, the insulating substrate on which the second conductive layer was thus formed was repeatedly washed with pure water five times. Next, draining was performed with 105 ° C. dry air passed through a high-performance filter, and the film was sufficiently dried. Thereafter, sampling is performed at points 10 m, 50 m, and 90 m from one end of the insulating substrate on which the second conductive layer is formed in this way, and the cross section is cut using a FIB apparatus to measure the thickness of the second conductive layer. As a result, each point was 13.5 μm in common on both the front and back surfaces of the insulating substrate, and the inside of the via hole was completely filled and there was no cavity.
[0118]
Next, in order to remove the resist, caustic soda 100 g / l, temperature 60 ° C., spray pressure 2.0 kg / cm using a resist peeling apparatus. ² The resist was peeled off under the conditions (see FIG. 4G, the configuration of the hole portion is different as described above).
[0119]
Subsequently, in order to remove the first conductive layer in the portion where the resist is removed, ammonium persulfate 50 g / l, temperature 35 ° C., spray pressure 1.5 kg / cm using an etching apparatus. ² By removing the first conductive layer by soft etching under the conditions of the above, the conductive sheet for the antenna non-contact type IC card of the present invention was obtained (see FIG. Is different).
[0120]
In addition, the electroless plating process is performed on the conductive layer on which the above circuit is formed using an electroless Sn plating solution (trade name: Substar Sn, manufactured by Okuno Pharmaceutical Co., Ltd.) at a temperature of 28 ° C. Thus, an antioxidant layer made of Sn was formed. When the thickness of the antioxidant layer was measured using a fluorescent X-ray film thickness meter (trade name: # 3200, manufactured by Seiko), the thickness of the antioxidant layer was 0.09 μm.
[0121]
Subsequently, electroless plating is performed at a temperature of 28 ° C. using an electroless Sn plating solution (trade name: Substar Sn, manufactured by Okuno Pharmaceutical Co., Ltd.) on the portion to be connected to the integrated circuit on the above antioxidant layer. By performing the treatment, a connection layer made of Sn was formed. When the thickness of this connection layer was measured using a fluorescent X-ray film thickness meter (trade name: # 3200, manufactured by Seiko), the thickness was 5 μm.
[0122]
In the conductive sheet for the non-contact type IC card with a built-in antenna obtained in this way, a part of the circuit of the conductive layer constitutes a coiled antenna, and there is no problem in electrical conductivity on both the front and back sides. It showed highly reliable electrical connectivity, and had good circuit pattern formability and good production efficiency.
[0123]
It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[0124]
【The invention's effect】
The conductive sheet for a non-contact IC card with a built-in antenna of the present invention has highly reliable electrical connectivity, good circuit pattern formability and good production efficiency. In addition, since the conductive layer is formed directly on the insulating substrate without using an adhesive, all problems resulting from the use of the adhesive are eliminated.
[Brief description of the drawings]
FIG. 1 is a schematic plan view of a conductive sheet for a non-contact IC card with a built-in antenna.
FIG. 2 is a schematic cross-sectional view taken along line II-II in the schematic plan view.
FIG. 3 is a manufacturing process diagram of a conductive sheet for a non-contact IC card with a built-in antenna.
FIG. 4 is another manufacturing process diagram of a conductive sheet for a non-contact IC card with a built-in antenna.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Conductive sheet for non-contact IC cards with built-in antenna, 2 Insulating substrate, 3 conductive layer, 3a 1st conductive layer, 3b 2nd conductive layer, 4 antenna, 5 through hole or via hole, 5a through hole, 6 integrated circuit, 7 resist, 8 mask, 9 part not forming circuit, 10 circuit, 11 part forming circuit.

[0012]
[Means for Solving the Problems]
The conductive sheet for a non-contact IC card with a built-in antenna of the present invention has conductive layers formed on both front and back surfaces of an insulating substrate, and the conductive layers on both surfaces are opened so as to penetrate the insulating substrate. A conductive sheet electrically connected to each other through a through hole or a via hole, wherein the conductive layer is formed directly on the insulating substrate, and the wall surface of the through hole or the inside of the via hole If has the same configuration in the front and back surfaces of the insulative substrate and the conductive layer constitutes a circuit including the antenna, and the conductive layer, the first conductive formed by the sputtering method or the vapor deposition method And a second conductive layer formed by an electroless plating method or an electroplating method. The first conductive layer further includes a layer for preventing deterioration of adhesion strength on the insulating substrate, and the adhesion strength. Inferiority Is characterized by comprising a layer which is excellent in adhesion between the second conductive layer has good electrical properties, which is formed on the layer to prevent.

[0048]
The first conductive layer is formed by first laminating a metal such as Ni, Cr, Ti or an alloy containing the metal on an insulating substrate, and laminating a metal such as Cu or an alloy containing the metal on the metal. Is preferred. A metal such as Cu is advantageous for use in such applications because it has good electrical characteristics, is excellent in adhesion to the second conductive layer, and is relatively inexpensive. In addition, there is a problem that the electrical characteristics are impaired. Therefore, in order to solve this problem of oxidation, a metal having oxidation resistance, for example, a metal such as Ni, Cr, Ti, etc., is formed under such a metal layer such as Cu (that is, between the insulating base). If the layer is formed, it is possible to prevent deterioration of the adhesion force over time due to oxidation.

[0012]
[Means for Solving the Problems]
The conductive sheet for a non-contact IC card with a built-in antenna of the present invention has conductive layers formed on both front and back surfaces of an insulating substrate, and the conductive layers on both surfaces are opened so as to penetrate the insulating substrate. A conductive sheet electrically connected to each other through a through hole or a via hole, wherein the conductive layer is formed directly on the insulating substrate, and the wall surface of the through hole or the inside of the via hole And the front and back surfaces of the insulating substrate have the same configuration, the conductive layer constitutes a circuit including an antenna, and the conductive layer is formed by a sputtering method or a vapor deposition method. And a second conductive layer formed by an electroless plating method or an electroplating method, and the first conductive layer is formed to a thickness of 500 to 5000 mm, and Ni is formed on the insulating substrate. Consists of a layer that prevents deterioration of the adhesion force having a thickness of 10 to 200 mm composed of Cr, Ti, or an alloy containing these metals, and Cu or Cu alloy formed on the layer that prevents the deterioration of adhesion force It is characterized by comprising a layer which is excellent in adhesion between the second conductive layer has good electrical properties are.

Claims (8)

Conductive layers are formed on both front and back surfaces of the insulating substrate, and the conductive layers on both front and back surfaces are electrically connected to each other through through holes or via holes that are opened so as to penetrate the insulating substrate. Sex sheet,
The conductive layer is directly formed on the insulating substrate, and has the same configuration on the wall surface of the through hole or the inside of the via hole and on both the front and back surfaces of the insulating substrate,
And the conductive layer constitutes a circuit including an antenna,
Conductive sheet for non-contact IC card with built-in antenna. The contactless IC with a built-in antenna according to claim 1, wherein the conductive layer is formed in the same process on the wall surface of the through-hole or the inside of the via hole and on both the front and back surfaces of the insulating substrate. Conductive sheet for cards. The conductive sheet for a non-contact type IC card with built-in antenna according to claim 1, wherein the conductive layer forms a circuit including an antenna by etching. The said conductive layer contains the 1st conductive layer formed by sputtering method or a vapor deposition method, and the 2nd conductive layer formed by the electroless-plating method or the electroplating method of Claim 1 characterized by the above-mentioned. Conductive sheet for non-contact IC card with built-in antenna. A circuit including an antenna is formed by masking a portion on the first conductive layer with a resist and then forming the second conductive layer on a portion not masked with the resist. 5. A conductive sheet for a non-contact IC card with a built-in antenna according to claim 4. A connection layer having a thickness of 0.2 to 15 μm is formed on the surface of the conductive layer from at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn, and Cr, or an alloy containing at least one metal. The conductive sheet for a non-contact type IC card with a built-in antenna according to claim 1, wherein the conductive sheet is used. An antioxidant layer having a thickness of 0.01 to 2 μm is formed on the surface of the conductive layer with at least one metal selected from the group consisting of Sn, Ni, Au, Ag, Zn, and Cr, or an alloy containing at least one metal. The conductive sheet for a non-contact type IC card with a built-in antenna according to claim 1, wherein the conductive sheet is formed. A non-contact type IC card with a built-in antenna, wherein the conductive sheet for a non-contact type IC card with a built-in antenna according to claim 1 is used.

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