Electric circuit for smart card, manufacturing method therefor, and smart card comprising electric circuit

Abstract

An electric circuit for a smart card, a manufacturing method therefor, and a smart card comprising the electric circuit are disclosed. The disclosed electric circuit for a smart card may comprise: a substrate; a first circuit pattern which is disposed on the substrate and which includes a conductor; and a metallic contact layer which is formed on the substrate to cover the first circuit pattern, and which has two or more types of metallic surface colors exposed toward a contact surface of the electric circuit. The metallic contact layer can include: a first color layer formed of a first material so as to have a first color; and a second color layer formed of a second material so as to have a second color that is different from the first color, wherein at least a portion of the first color layer and at least a portion of the second color layer can be exposed toward the contact surface. The first color layer can be a first plating layer and the second color layer can be a second plating layer.

Description

Electrical circuit for smart card, manufacturing method thereof, and smart card including electrical circuit

[0001] The present invention relates to electronic / semiconductor devices and devices / equipment using the same, and more specifically, to an electric circuit for a smart card, a manufacturing method thereof, and a smart card including the electric circuit.

[0002] A smart card (also known as a chip card or integrated circuit card) is a plastic card with a built-in microprocessor and memory, enabling data storage and processing. The most common type is one that resembles a credit card in shape and size. Recently, various technologies related to smart cards have been developing rapidly. In particular, advancements in semiconductor and component technology have significantly increased the processing power and memory capacity of smart cards. Furthermore, interface functionality that can be integrated into smart cards is also improving significantly.

[0003] Smart cards can be categorized into several types, depending on whether they contain a microprocessor, their interface method, or their stage of evolution. Smart cards can function in a variety of ways, from keys carried around with people to wallets, ID cards, and ultimately personal computers. Due to this versatility, the smart card market is rapidly growing.

[0004] However, in the case of the substrates (i.e., electrical circuits) for the IC (integrated circuit) chips used in existing smart cards, the surface color is standardized or limited to gold or silver due to manufacturing method limitations. Since the surface (contact surface) of the IC chip substrate (i.e., electrical circuits) is uniformly colored in a single color, it is difficult to create sophisticated colors or emotional or design functions / values, and in this regard, there is a problem that it is difficult to meet the diverse needs of consumers (users). Therefore, a technology is required that can overcome these problems and enhance the surface color of the electrical circuits for smart cards and implement emotional colors / designs.

[0005] The technical problem to be achieved by the present invention is to provide an electric circuit for a smart card and a manufacturing method thereof, which can diversify / upgrade the color of a metal contact surface (contact surface) to two or more types, which was limited due to existing technical limitations, and enable the application of various designs (patterns), thereby improving aesthetics (visual characteristics), while easily securing excellent electrical characteristics.

[0006] The technical task to be achieved by the present invention is to provide an electric circuit for a smart card and a manufacturing method thereof that can create emotional / design added value with two or more surface colors, breaking away from the monotony of the existing metal contact surface color.

[0007] In addition, a technical problem to be achieved by the present invention is to provide a smart card including the above-described electric circuit.

[0008] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0009] According to embodiments of the present invention for achieving the above-described object, there is provided an electric circuit for a smart card, comprising: a substrate; a first circuit pattern disposed on the substrate and including a conductor; and a metallic contact layer formed on the substrate to cover the first circuit pattern, the metallic contact layer having two or more metallic surface colors exposed toward a contact surface of the electric circuit; wherein the metallic contact layer includes a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and wherein at least a portion of the first color layer and at least a portion of the second color layer are exposed toward the contact surface.

[0010] According to embodiments of the present invention, it is possible to implement an electric circuit for a smart card that can diversify / upscale the colors of a metal contact surface (contact surface) that were limited due to existing technical limitations to two or more types and enable the application of various designs (patterns), thereby improving aesthetics (visual characteristics) while easily securing excellent electrical characteristics. According to embodiments, it is possible to implement an electric circuit for a smart card that can create emotional / design added value with two or more surface colors, breaking away from the monotony of existing metal contact surface (contact surface) colors.

[0011] By applying the electric circuit for a smart card according to these embodiments, a smart card that can satisfy various needs of consumers (users) can be manufactured.

[0012] However, the effects of the present invention are not limited to the above effects, and can be expanded in various ways without departing from the technical spirit and scope of the present invention.

[0013] FIG. 1 is a cross-sectional view illustrating an electric circuit for a smart card according to one embodiment of the present invention.

[0014] FIG. 2 is a photographic image showing a contact surface of an electric circuit for a smart card according to one embodiment of the present invention.

[0015] FIG. 3 is a photographic image showing a contact surface of an electric circuit for a smart card according to various embodiments of the present invention.

[0016] Figure 4 is a photographic image showing a contact surface of an electric circuit according to a comparative example.

[0017] FIG. 5 is an image showing a smart card to which an electric circuit for a smart card according to one embodiment of the present invention is applied.

[0018] FIGS. 6 to 11 are cross-sectional views illustrating a method for manufacturing an electric circuit for a smart card according to an exemplary embodiment of the present invention.

[0019] FIG. 12 is a drawing for explaining a method for manufacturing an electric circuit for a smart card according to an exemplary embodiment of the present invention.

[0020] FIG. 13 is a drawing for explaining a method for manufacturing an electric circuit for a smart card according to an embodiment of the present invention.

[0021] According to embodiments of the present invention for achieving the above-described object, there is provided an electric circuit for a smart card, comprising: a substrate; a first circuit pattern disposed on the substrate and including a conductor; and a metallic contact layer formed on the substrate to cover the first circuit pattern, the metallic contact layer having two or more metallic surface colors exposed toward a contact surface of the electric circuit; wherein the metallic contact layer includes a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and wherein at least a portion of the first color layer and at least a portion of the second color layer are exposed toward the contact surface.

[0022] The first color layer may be a first plating layer, and the second color layer may be a second plating layer.

[0023] The first color layer may include one of Au, Pd, Ag, and Ni, and the second color layer may include another one of Au, Pd, Ag, and Ni.

[0024] A plurality of contact pad regions may be defined on the contact surface of the electric circuit, and at least two of the plurality of contact pad regions may have different metallic surface colors, or different metallic surface colors may be applied within one of the plurality of contact pad regions.

[0025] A plurality of contact pad areas and pattern areas can be defined on the contact surface of the electric circuit, and the pattern area can include at least one of letters, numbers, symbols, and picture designs, and two or more types of metallic surface colors can be applied to at least one of the plurality of contact pad areas and pattern areas.

[0026] The plurality of contact pad regions may be arranged to surround the pattern region.

[0027] A portion of the first color layer may be covered by the second color layer and not be exposed to the contact surface.

[0028] The above first circuit pattern may have at least one structure among a Cu / Ni / Au stacked structure, a Cu / Ni / Au / Pd stacked structure, a Cu / Ni / Pd / Au stacked structure, a Cu / Ni / Pd stacked structure, a Cu / Pd stacked structure, a Cu / Ni stacked structure, a Cu / Au stacked structure, and a Cu single-layer structure.

[0029] The first circuit pattern may be arranged on a first surface of the substrate, and the electric circuit for the smart card may further include a second circuit pattern arranged on a second surface of the substrate; and a plating layer formed on the second surface of the substrate to cover the second circuit pattern.

[0030] According to other embodiments of the present invention, a smart card including the electrical circuit for the smart card described above is provided.

[0031] According to other embodiments of the present invention, a method for manufacturing an electric circuit for a smart card is provided, comprising: providing an electric circuit element structure having a first circuit pattern including a conductor on a substrate; and forming a metallic contact layer having two or more metallic surface colors that are exposed toward a contact surface of the electric circuit by covering the first circuit pattern on the substrate; wherein the metallic contact layer is configured to include a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and at least a portion of the first color layer and at least a portion of the second color layer are exposed toward the contact surface.

[0032] The first color layer may be a first plating layer, and the second color layer may be a second plating layer.

[0033] The first color layer may include one of Au, Pd, Ag, and Ni, and the second color layer may include another one of Au, Pd, Ag, and Ni.

[0034] The step of forming the metallic contact layer may include: forming the first color layer covering the first circuit pattern on the substrate by plating; forming a mask material layer covering the first color layer on the substrate; forming a mask pattern having an opening that exposes a portion of the first color layer from the mask material layer by removing a portion of the mask material layer; forming the second color layer by plating on a portion of the first color layer exposed by the opening; and removing the mask pattern.

[0035] After the step of forming the mask material layer, a step of pressurizing the mask material layer may be further included.

[0036] A portion of the first color layer may be covered by the second color layer and not be exposed to the contact surface.

[0037] The first circuit pattern may be arranged on a first surface of the substrate, the device structure may further include a second circuit pattern arranged on a second surface of the substrate, and the method for manufacturing an electric circuit for a smart card may further include a step of forming a plating layer covering the second circuit pattern on the second surface of the substrate.

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0039] The embodiments of the present invention described below are provided to more clearly explain the present invention to a person having ordinary skill in the art, and the scope of the present invention is not limited by the following embodiments, and the following embodiments can be modified in various other forms.

[0040] The terminology used herein is used to describe particular embodiments and is not intended to limit the present invention. The singular forms used herein may include the plural forms unless the context clearly dictates otherwise. In addition, the terms "comprise" and / or "comprising" used herein specify the presence of a stated feature, step, number, operation, element, element, and / or group thereof, but do not exclude the presence or addition of one or more other features, steps, numbers, operations, elements, elements, and / or groups thereof. In addition, the term "connected" used herein not only means that certain elements are directly connected, but also includes a concept that indirectly connects elements by interposing another element between them.

[0041] In addition, when it is said in this specification that a certain element is located "on" another element, this includes not only cases where a certain element is in contact with another element, but also cases where another element exists between the two elements. The term "and / or" as used in this specification includes any one of the listed items and any and all combinations of one or more of them. In addition, terms of degree such as "about", "substantially", etc. as used in this specification are used to mean a range of or close to the numerical value or degree, taking into account inherent manufacturing and material tolerances, and are used to prevent infringers from unfairly using the disclosure that mentions exact or absolute numbers provided to help the understanding of this specification.

[0042] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The sizes and thicknesses of areas or parts illustrated in the attached drawings may be somewhat exaggerated for clarity and convenience of explanation. Like reference numbers designate like components throughout the detailed description.

[0043] Fig. 1 is a cross-sectional view illustrating an electric circuit for a smart card according to one embodiment of the present invention. The structure illustrated in Fig. 1 may be a substrate structure for an IC chip (i.e., an electric circuit substrate), and an IC chip (not shown) may be bonded to a bonding surface (i.e., S2) of the substrate structure for the IC chip.

[0044] Referring to FIG. 1, an electric circuit for a smart card according to an embodiment of the present invention may include a substrate (S10) and a first circuit pattern (P10) disposed on the substrate (S10). The substrate (S10) may be an insulating substrate. In addition, the substrate (S10) may be a flexible substrate. The substrate (S10) may include a polymer or be composed of a polymer. For example, the substrate (S10) may include an epoxy or be composed of an epoxy. However, the material of the substrate (S10) is not limited to epoxy and may vary. When a substrate (S10) having flexible characteristics is used, the electric circuit may have flexible characteristics.

[0045] The first circuit pattern (P10) may include a conductor or be formed of a conductor. The first circuit pattern (P10) may be formed on a first surface (either the upper or lower surface) of the substrate (S10). Here, for convenience, the first circuit pattern (P10) is simply illustrated, but in reality, the first circuit pattern (P10) may have a more complex structure than that illustrated herein. The first circuit pattern (P10) may include a plurality of pattern portions spaced apart from each other, and the surface of the substrate (S10) may be exposed between the plurality of pattern portions. The first circuit pattern (P10) may have a laminated structure in which a plurality of conductive layers are laminated. For example, the first circuit pattern (P10) may have at least one structure among a Cu / Ni / Au stacked structure, a Cu / Ni / Au / Pd stacked structure, a Cu / Ni / Pd / Au stacked structure, a Cu / Ni / Pd stacked structure, a Cu / Pd stacked structure, a Cu / Ni stacked structure, a Cu / Au stacked structure, and a Cu single-layer structure. The arrangement order of the metal layers in the stacked structures is described in a direction away from the substrate (S10). For example, in the case of the Cu / Ni / Au stacked structure, this represents a case where a Cu layer is formed on the substrate (S10), a Ni layer is formed on the Cu layer, and an Au layer is formed on the Ni layer.

[0046] Although not illustrated in FIG. 1, a predetermined adhesive layer may be further provided between the substrate (S10) and the first circuit pattern (P10). The adhesive layer may have a patterned structure or a continuous layer structure. The adhesive layer may include an insulating material and may be considered a part of the substrate (S10). In other words, the adhesive layer may be considered to be included in the substrate (S10).

[0047] The above-described electric circuit for a smart card may include a metallic contact layer (C10) formed to cover a first circuit pattern (P10) on a substrate (S10). The metallic contact layer (C10) may be configured to have two or more metallic surface colors exposed toward a contact surface (S1) of the electric circuit. The contact surface (S1) may be a surface on which the first circuit pattern (P10) is formed among both surfaces of the electric circuit.

[0048] The metallic contact layer (C10) may include a first color layer (L10) formed of a first material to have a first color and a second color layer (L20) formed of a second material to have a second color different from the first color. The first material may include a metal or a metallic material. The second material may be different from the first material and may include a metal or a metallic material. At least a portion of the first color layer (L10) and at least a portion of the second color layer (L20) may be exposed toward the contact surface (S1).

[0049] According to one embodiment, the first color layer (L10) may be a first plating layer, and the second color layer (L20) may be a second plating layer. The first and second color layers (L10, L20) may be plating layers (metal layers) formed by a plating method. As a non-limiting example, the first color layer (L10) may be formed by a plating method on a surface of the first circuit pattern (P10). The second color layer (L20) may be formed by a plating method on a portion of the first color layer (L10).

[0050] The first and second color layers (L10, L20) may include different metals. For example, the first color layer (L10) may include one of Au, Pd, Ag, and Ni, and the second color layer (L20) may include another of Au, Pd, Ag, and Ni. The first color layer (L10) may be formed of one of Au, Pd, Ag, and Ni, and the second color layer (L20) may be formed of another of Au, Pd, Ag, and Ni. Here, Au may have a gold color, and Pd and Ag may have a silver color. However, the specific materials of the first and second color layers (L10, L20) are not limited to those described above, and may vary depending on the case. In addition, the colors exhibited by the first and second color layers (L10, L20) may be more diverse than silver and gold.

[0051] According to one embodiment, a portion of the first color layer (L10) may be covered by the second color layer (L20) and not be exposed toward the contact surface (S1). In this case, the portion of the first color layer (L10) covered by the second color layer (L20) may serve as a plating seed for forming the second color layer (L20). However, the embodiment of the present invention is not limited thereto. That is, the entire first color layer (L10) may not be covered by the second color layer (L20), and they (L10, L20) may be formed separately. In this case, the entire first color layer (L10) may be exposed toward the contact surface (S1), and the entire second color layer (L20) may also be exposed toward the contact surface (S1).

[0052] In addition, according to one embodiment, the electric circuit for the smart card may further include a second circuit pattern (P20) disposed on a second surface (either the upper or lower surface) of the substrate (S10) and a metallic material layer (L15) formed to cover the second circuit pattern (P20) on the second surface of the substrate (S10). The second surface of the substrate (S10) may be a surface facing (opposite) the first surface. The metallic material layer (L15) may be referred to as a metallic surface layer. According to one example, the metallic material layer (L15) may be a plating layer. The metallic material layer (L15) may include, but is not limited to, any one of Au, Pd, Ag, and Ni, or may be formed of any one of Au, Pd, Ag, and Ni. The second circuit pattern (P20) and the metallic material layer (L15) can be placed on the bonding surface (S2) side of the electric circuit.

[0053] The thickness of the first color layer (L10) may be, for non-limiting examples, in the range of about 0.5 to 45 μm. The thickness of the second color layer (L20) may be, for non-limiting examples, in the range of about 0.005 to 15 μm. The thickness of the metallic material layer (L15) may be, for non-limiting examples, in the range of about 0.005 to 15 μm. The first color layer (L10), the second color layer (L20), and the metallic material layer (L15) may have low electrical resistance characteristics required in an electric circuit for a smart card.

[0054] The cross-sectional structure of the electric circuit for a smart card according to the embodiment illustrated in FIG. 1 is simplified, partial, and exemplary, and the cross-sectional structure of an actual electric circuit may be more complex than that illustrated in FIG. 1.

[0055] FIG. 2 is a photographic image showing a contact surface of an electric circuit for a smart card according to one embodiment of the present invention.

[0056] Referring to FIG. 2, a plurality of contact pad areas (A10) may be defined on a contact surface (S1 of FIG. 1) of an electric circuit for a smart card according to an embodiment of the present invention. The plurality of contact pad areas (A10) may have an array structure of contact pads for communication. In addition, a pattern area (B10) may be further defined on the contact surface of the electric circuit for the smart card. The pattern area may be configured to include at least one of letters, numbers, symbols, and picture designs. According to an example, the plurality of contact pad areas (A10) may be arranged to surround the pattern area (B10). That is, in a planar image viewed from above, the plurality of contact pad areas (A10) may be arranged to surround the pattern area (B10) in all directions. In this case, the aesthetic characteristics and effects may be enhanced, and it may also be advantageous in securing the function of the contact surface. However, the positional relationship between the plurality of contact pad areas (A10) and the pattern area (B10) is not limited to the above and may be changed.

[0057] According to one embodiment, the "two or more metallic surface colors" described in FIG. 1 may be applied to at least one of the plurality of contact pad areas (A10) and the pattern area (B10). In the embodiment of FIG. 2, the case where the contact pad area (A10) has a first color and the pattern area (B10) has a second color is exemplified. However, the "two or more metallic surface colors" may be applied within the plurality of contact pad areas (A10), and / or the "two or more metallic surface colors" may be applied within the pattern area (B10). In the former case, that is, when the "two or more metallic surface colors" are applied within the plurality of contact pad areas (A10), at least two of the plurality of contact pad areas (A10) may have different metallic surface colors, or different metallic surface colors may be applied within one contact pad area among the plurality of contact pad areas (A10). Different colors can be implemented for each contact pad area, and different colors can be applied within the same contact pad area without restrictions on shape and design. Therefore, the diversification and sophistication of colors and designs within the contact surface can be easily realized.

[0058] FIG. 3 is a photographic image showing a contact surface of an electric circuit for a smart card according to various embodiments of the present invention.

[0059] Referring to FIG. 3, the electrical circuit for a smart card according to an embodiment of the present invention may have various designs and color combinations as shown in drawings (A) to (H). "Two or more metallic surface colors" as described above may be applied in various ways to at least one of the multiple contact pad areas and the pattern areas.

[0060] Figure 4 is a photographic image showing a contact surface of an electric circuit according to a comparative example.

[0061] Referring to Fig. 4, the contact surface of the electric circuit according to the comparative example may have a single color, gold. In the case of electric circuits applied to existing smart cards, the surface color is uniformly or limited to gold or silver due to limitations in manufacturing methods, etc. Since the color of the surface part (contact surface) of the electric circuit is uniformly monochromatic, it is difficult to create sophisticated colors or emotional and design functions / values, and in this regard, there was a problem that it was difficult to meet the diverse needs of consumers (users). However, according to an embodiment of the present invention, it is possible to implement an electric circuit for a smart card that can create emotional / design added value with two or more surface colors, breaking away from the monotony of the color of the existing metal contact surface (contact surface).

[0062] FIG. 5 is an image showing a smart card (100) to which an electric circuit (50) for a smart card according to one embodiment of the present invention is applied.

[0063] Referring to FIG. 5, a smart card (100) according to an embodiment of the present invention may include an electric circuit (50) having two or more metallic surface colors exposed on the contact surface side as described above. The electric circuit (50) may include a pattern area, and various designs (possibly including characters) may be applied to the pattern area. The electric circuit (50) having two or more metallic surface colors may be built into and installed within a predetermined area of ​​the plastic card body. At this time, the contact surface of the electric circuit (50) may be exposed to the outside of the smart card (100).

[0064] According to embodiments of the present invention, it is possible to implement an electric circuit for a smart card that can diversify / upscale the colors of a metal contact surface (contact surface) that were limited due to existing technical limitations to two or more types and enable the application of various designs (patterns), thereby improving aesthetics (visual characteristics) while easily securing excellent electrical characteristics. According to embodiments, it is possible to create visual added value by adding an emotional function to the electrical communication function of a wireless communication chip card. It is possible to create emotional / design added value by applying two or more types of surface colors and applying various designs, breaking away from the monotony of existing colors and designs. By applying the electric circuit for a smart card according to these embodiments, it is possible to manufacture a smart card that can satisfy various needs of consumers (users).

[0065] Hereinafter, a method for manufacturing an electric circuit for a smart card according to an embodiment of the present invention will be described.

[0066] A method for manufacturing an electric circuit for a smart card according to one embodiment of the present invention may include the steps of providing an electric circuit element structure having a first circuit pattern including a conductor on a substrate, and the step of forming a metallic contact layer having two or more metallic surface colors that cover the first circuit pattern on the substrate and are exposed toward a contact surface of the electric circuit. The metallic contact layer may be configured to include a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and at least a portion of the first color layer and at least a portion of the second color layer may be exposed toward the contact surface.

[0067] In one embodiment, the first color layer may be a first plating layer, and the second color layer may be a second plating layer. The first and second color layers may be plating layers (metal layers) formed by a plating method. As a non-limiting example, the first color layer may be formed by a plating method on a surface of the first circuit pattern. The second color layer may be formed by a plating method on a portion of the first color layer.

[0068] The first and second color layers may include different metals. As a specific example, the first color layer may include any one of Au, Pd, Ag, and Ni, and the second color layer may include another one of Au, Pd, Ag, and Ni. The first color layer may be formed of any one of Au, Pd, Ag, and Ni, and the second color layer may be formed of another one of Au, Pd, Ag, and Ni. Here, Au may exhibit a gold color, and Pd and Ag may exhibit a silver color. However, the specific materials of the first and second color layers are not limited to those described above, and may vary in various ways depending on the case. In addition, the colors exhibited by the first and second color layers may be more diverse than silver and gold.

[0069] In one embodiment, a portion of the first color layer may be covered by the second color layer and not exposed toward the contact surface. In this case, the portion of the first color layer covered by the second color layer may serve as a plating seed for forming the second color layer. However, the embodiment of the present invention is not limited thereto. That is, the entire first color layer may not be covered by the second color layer, and the first and second color layers may be formed separately. In this case, the entire first color layer may be exposed toward the contact surface, and the entire second color layer may also be exposed toward the contact surface.

[0070] In addition, according to one embodiment, the first circuit pattern may be disposed on a first surface of the substrate, and the device structure may further include a second circuit pattern disposed on a second surface of the substrate. The second surface of the substrate may be a surface facing (opposite) to the first surface. The method for manufacturing an electric circuit for a smart card may further include a step of forming a metallic material layer covering the second circuit pattern on the second surface of the substrate. The metallic material layer may be referred to as a metallic surface layer. According to one example, the metallic material layer may be a plating layer. The metallic material layer may include, but is not limited to, any one of Au, Pd, Ag, and Ni, or may be formed of any one of Au, Pd, Ag, and Ni. The second circuit pattern and the metallic material layer may be disposed on a bonding surface side of the electric circuit.

[0071] FIGS. 6 to 11 are cross-sectional views illustrating a method for manufacturing an electric circuit for a smart card according to an exemplary embodiment of the present invention.

[0072] Referring to FIG. 6, an electric circuit device structure having a first circuit pattern (P10) including a conductor on a substrate (S10) can be prepared. The first circuit pattern (P10) can be arranged on a first surface of the substrate (S10). The device structure can further include a second circuit pattern (P20) arranged on a second surface of the substrate (S10). The first surface can be one of the upper and lower surfaces of the substrate (S10), and the second surface can be the other of the upper and lower surfaces of the substrate (S10). In the device structure, a surface on which the first circuit pattern (P10) is formed can correspond to a contact surface (S1) of the electric circuit, and a surface on which the second circuit pattern (P20) is formed can correspond to a bonding surface (S2) of the electric circuit.

[0073] A first color layer (L10) covering a first circuit pattern (P10) can be formed on the first surface of the substrate (S10). The first color layer (L10) can have a first color and can be formed of a first material. The first color layer (L10) can be formed on the surface of the first circuit pattern (P10) by a plating method. For example, the first color layer (L10) can include any one of Au, Pd, Ag, and Ni, or can be formed of any one of Au, Pd, Ag, and Ni.

[0074] In addition, a metallic material layer (L15) covering a second circuit pattern (P20) may be formed on the second surface of the substrate (S10). The metallic material layer (L15) may be formed on the surface of the second circuit pattern (P20) by a plating method. Therefore, the metallic material layer (L15) may be a plating layer. The metallic material layer (L15) may include, for example, any one of Au, Pd, Ag, and Ni, or may be formed of any one of Au, Pd, Ag, and Ni. The metallic material layer (L15) may be formed of a different material from the first color layer (L10), but in some cases, may be formed of the same material.

[0075] Referring to FIG. 7, a mask material layer (M10) covering a first color layer (L10) may be formed on a substrate (S10). The mask material layer (M10) may include, for example, a photoresist (a photosensitive film material). Therefore, the mask material layer (M10) may be a photoresist layer. The mask material layer (M10) may be a type of dry film. In some cases, the mask material layer (M10) may not completely fill the space between a plurality of pattern portions constituting the first circuit pattern (P10). In this case, the lower surface of the mask material layer (M10) may not contact the surface (the first surface) of the substrate (S10) and a gap may exist between them.

[0076] Referring to FIG. 8, a process of pressurizing the mask material layer (M10) (i.e., a pressurizing process) can be performed. By pressurizing the mask material layer (M10), a gap between the mask material layer (M10) and the surface (the first surface) of the substrate (S10) can be removed, and the space between the plurality of pattern portions constituting the first circuit pattern (P10) can be completely (or almost completely) filled with the material of the mask material layer (M10). The pressurizing process can be performed using, for example, an autoclave. In this case, a pressure of, for example, about 15 to 250 PSI can be applied to the mask material layer (M10) in the pressurizing process.

[0077] However, the pressurizing process may be optional. In the step of FIG. 7, the mask material layer (M10) may be formed to completely or substantially fill the space between the plurality of pattern portions constituting the first circuit pattern (P10), in which case the pressurizing process may be omitted.

[0078] Referring to FIG. 9, a mask pattern (M10a) having an opening (H10) exposing a portion of a first color layer (L10) from the mask material layer (M10) can be formed by removing a portion of the mask material layer (M10). An exposure and development process can be performed on the mask material layer (M10) to form a patterned mask pattern (M10a) from the mask material layer (M10).

[0079] Referring to Fig. 10, a second color layer (L20) can be formed on a portion of the first color layer (L10) exposed by the opening (H10). The second color layer (L20) can have a second color different from the first color and can be formed of a second material different from the first material. The second color layer (L20) can be formed by plating on the surface of the portion of the first color layer (L10) exposed by the opening (H10). For example, the second color layer (L20) can include any one of Au, Pd, Ag, and Ni, or can be formed of any one of Au, Pd, Ag, and Ni. The second color layer (L20) can be formed of a different material from the first color layer (L10) and can exhibit a different color from the first color layer (L10).

[0080] Referring to Fig. 11, the mask pattern (M10a) can be removed. The mask pattern (M10a) can be removed using a peeling method or other method. The first color layer (L10) and the second color layer (L20) can form a metallic contact layer (C10). The metallic contact layer (C10) can be configured to have two or more metallic surface colors that are exposed toward the contact surface (S1) of the electric circuit. At least a portion of the first color layer (L10) and at least a portion of the second color layer (L20) can be exposed toward the contact surface (S1). The electric circuit structure of Fig. 11 can be the same as the electric circuit structure described in Fig. 1. Therefore, all of the features described for the electric circuit in Fig. 1 can be applied to the electric circuit of Fig. 11.

[0081] According to one embodiment of the present invention, as described with reference to FIGS. 6 to 11, an electric circuit including a metallic contact layer (C10) having two or more metallic surface colors can be manufactured through selective surface plating treatment. At this time, a resist material for heterogeneous plating treatment can be used. However, the method for manufacturing an electric circuit according to an embodiment of the present invention is not limited to that described with reference to FIGS. 6 to 11, and may be varied in various ways.

[0082] FIG. 12 is a drawing for explaining a method for manufacturing an electric circuit for a smart card according to an exemplary embodiment of the present invention.

[0083] Figures 12A to 12F show contact surface side images of the electric circuit at each manufacturing step. Figure 12A may correspond to step 6 of Figure 6, Figure 12B may correspond to step 7 of Figure 7, and Figure 12C may correspond to step 8 of Figure 8. Figure 12D may correspond to step 9 of Figure 9, Figure 12E may correspond to step 10 of Figure 12, and Figure 12F may correspond to step 11 of Figure 12. However, the manufacturing process and the result of the process illustrated in Figure 12 are merely exemplary and may vary.

[0084] FIG. 13 is a drawing for explaining a method for manufacturing an electric circuit for a smart card according to an embodiment of the present invention.

[0085] Referring to Figure 13, various results can be obtained from the same electrical circuit element structure (starting element structure) depending on the specific process method. By applying two or more colors and various designs / patterns, unique and emotional electrical circuits and smart cards including them can be realized, satisfying the diverse needs of consumers.

[0086] According to the embodiments of the present invention described above, it is possible to implement an electric circuit for a smart card that can diversify / upscale the colors of the metal contact surface (contact surface) that were limited due to existing technical limitations to two or more types and enable the application of various designs (patterns), thereby improving the aesthetics (visual characteristics) while easily securing excellent electrical characteristics. According to the embodiments, it is possible to create visual added value by adding an emotional function to the electrical communication function of a wireless communication chip card. It is possible to create emotional / design added value by applying two or more surface colors and applying various designs, breaking away from the monotony of existing colors and designs. The color of the surface of the communication module pad of an IC chip card can be diversified and a unique design can be implemented. By applying the electric circuit for a smart card according to these embodiments, it is possible to manufacture a smart card that can satisfy the diverse needs of consumers (users).

[0087] This specification discloses preferred embodiments of the present invention, and although specific terms are used, they are used only in a general sense to easily explain the technical contents of the present invention and to help understand the invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present invention are possible in addition to the embodiments disclosed herein. For example, those skilled in the art will appreciate that the electric circuit for a smart card according to the embodiments described with reference to FIGS. 1 to 3 and FIGS. 5 to 13, the manufacturing method thereof, and the smart card including the electric circuit can be modified in various ways. As a specific example, it will be appreciated that the electric circuit is illustrated simply, but in reality, it can have a more complex and elaborate circuit structure. It will be appreciated that the specific structure and manufacturing method of the electric circuit can be varied in various ways, and the fields of application of the electric circuit can also be varied in various ways. Additionally, it will be appreciated that three or more metallic surface colors may be applied to the contact surface of the electrical circuit, and in this case, the metallic contact layer may further include one or more additional color layers (e.g., additional plating layers) having one or more different colors. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the technical ideas described in the claims.

Claims

1. An electric circuit for a smart card, substrate; A first circuit pattern disposed on the substrate and including a conductor; and A metallic contact layer formed to cover the first circuit pattern on the substrate and configured to have two or more metallic surface colors exposed toward the contact surface of the electric circuit; An electric circuit for a smart card, wherein the metallic contact layer includes a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and at least a portion of the first color layer and at least a portion of the second color layer are exposed toward the contact surface.

2. In paragraph 1, The above first color layer is a first plating layer, The second color layer is an electric circuit for a smart card, which is a second plating layer.

3. In paragraph 1, The first color layer comprises one of Au, Pd, Ag and Ni, An electric circuit for a smart card, wherein the second color layer comprises another one of Au, Pd, Ag and Ni.

4. In paragraph 1, A plurality of contact pad areas are defined on the contact surface of the above electric circuit, An electrical circuit for a smart card, wherein at least two of the plurality of contact pad areas have different metallic surface colors, or wherein a different metallic surface color is applied within one of the plurality of contact pad areas.

5. In paragraph 1, A plurality of contact pad areas and a pattern area are defined on the contact surface of the above electric circuit, and the pattern area includes at least one of letters, numbers, symbols, and picture designs. An electrical circuit for a smart card, wherein two or more metallic surface colors are applied to at least one of the plurality of contact pad areas and pattern areas.

6. In paragraph 5, An electrical circuit for a smart card, wherein the plurality of contact pad areas are arranged to surround the pattern area.

7. In paragraph 1, An electric circuit for a smart card, wherein a part of the first color layer is covered by the second color layer and is not exposed toward the contact surface.

8. In paragraph 1, An electric circuit for a smart card, wherein the first circuit pattern has at least one structure among a Cu / Ni / Au laminated structure, a Cu / Ni / Au / Pd laminated structure, a Cu / Ni / Pd / Au laminated structure, a Cu / Ni / Pd laminated structure, a Cu / Pd laminated structure, a Cu / Ni laminated structure, a Cu / Au laminated structure, and a Cu single-layer structure.

9. In paragraph 1, The above first circuit pattern is arranged on the first surface of the substrate, An electric circuit for a smart card further comprising: a second circuit pattern disposed on a second surface of the substrate; and a plating layer formed on the second surface of the substrate to cover the second circuit pattern.

10. A smart card comprising an electric circuit for a smart card as described in any one of claims 1 to 9.

11. A method for manufacturing an electric circuit for a smart card, A step of providing an electrical circuit element structure having a first circuit pattern including a conductor on a substrate; and A step of forming a metallic contact layer having two or more metallic surface colors that are exposed toward the contact surface of the electric circuit by covering the first circuit pattern on the substrate; A method for manufacturing an electric circuit for a smart card, wherein the metallic contact layer is configured to include a first color layer formed of a first material to have a first color and a second color layer formed of a second material to have a second color different from the first color, and at least a portion of the first color layer and at least a portion of the second color layer are exposed toward the contact surface.

12. In paragraph 11, The above first color layer is a first plating layer, A method for manufacturing an electric circuit for a smart card, wherein the second color layer is a second plating layer.

13. In the 11th paragraph, the step of forming the metallic contact layer comprises: A step of forming the first color layer covering the first circuit pattern on the substrate by plating; A step of forming a mask material layer covering the first color layer on the substrate; A step of forming a mask pattern having an opening exposing a portion of the first color layer from the mask material layer by removing a portion of the mask material layer; A step of forming the second color layer by plating on the first color layer portion exposed by the opening; and A method for manufacturing an electric circuit for a smart card, comprising: a step of removing the above mask pattern.

14. In paragraph 11, A method for manufacturing an electric circuit for a smart card, wherein a part of the first color layer is covered by the second color layer and is not exposed to the contact surface side.

15. In paragraph 11, The above first circuit pattern is arranged on the first surface of the substrate, The above-described element structure further includes a second circuit pattern disposed on a second surface of the substrate, A method for manufacturing an electric circuit for a smart card, the method further comprising the step of forming a plating layer covering the second circuit pattern on the second surface of the substrate.

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