JP7533158B2 - IC module and information medium - Google Patents

Description

The present invention relates to an IC module that can prevent damage to an IC chip caused by localized pressure in media equipped with an IC chip, such as cards and passports, and to an information medium equipped with the IC module.

To protect the mold and lead frame of the IC chip built into the IC card from damage caused by localized pressure from the outside, a commonly used structure is the IC module, which uses a metal reinforcing material such as SUS bonded with adhesive.

In this type of structure, if the adhesive portion is made of a soft material (urethane resin, polyethylene resin, silicone resin, etc.), the adhesive portion will be easily crushed when an impact is applied from the reinforcing material side, and if the thickness is insufficient, the impact will be easily transmitted directly to the IC chip, causing the IC chip to be easily damaged.

On the other hand, if the adhesive portion is made of a hard material (metal, ceramic, epoxy resin, polyvinyl chloride resin, polyamide resin, etc.), there is no means to dissipate the shock when it is applied, so the shock is still likely to be transmitted directly to the IC chip, causing the IC chip to be easily damaged.

The adhesive part may also be made of fibers (glass, aramid, Kevlar, etc.) and adhesive, but in that case the adhesive surface is smooth and comes into contact with the entire surface of the reinforcing material, such as SUS, so any impact or bending deflection applied locally to the reinforcing material is likely to be transmitted to other parts of the adhesive part, and the impact is likely to be transmitted directly to the IC chip.

Patent Document 1 also discloses an IC card in which the adhesive in the center of the reinforcing material or IC chip has a high elasticity and the adhesive in the periphery has a low elasticity, and claims that by achieving uniform strength, an IC card that is resistant to bending stress and impact forces can be obtained. However, in this case, two types of adhesive must be prepared, and there is a tendency for the coating to vary, making it difficult to uniformize the strength. In addition, because the adhesive layer is a flat layer with a constant thickness and is in contact with the reinforcing material over its entire surface, there is a problem that impacts or bending deflections applied locally to the reinforcing material are easily transmitted to other parts of the adhesive layer, and damage is easily transmitted to the IC chip.

JP 4441850 A

The objective of the present invention is to provide an IC module and information medium that can prevent the IC chip from being destroyed by impact, even if a localized impact is applied from the reinforcing material side, by preventing the impact from being directly transmitted to the IC chip.

In order to solve the above problems, the present invention provides
An IC module in which an IC part in which an IC chip is encapsulated, an intermediate layer, and a reinforcing material are laminated in this order,
The intermediate layer has a plurality of protrusions formed on at least one of the IC portion side and the reinforcing material side,
The top of the protrusion is in contact with an opposing member,
The convex portion is characterized in that the top portion is formed at a position that is not directly above the IC chip.

In the above IC module, the protrusions may be formed in a staggered arrangement pattern.

In the above IC module, the protrusions may be formed in a radial arrangement pattern centered on the IC chip.

In the above IC module, the protrusions may be formed in a random arrangement pattern.

In the above IC module, the top may be smoothly curved.

In the IC module, the gaps between the protrusions of the intermediate layer may be filled with an adhesive having a lower elastic modulus than the material of the intermediate layer in a manner that does not fill the gaps.

Another aspect of the present invention is an information medium equipped with any of the above IC modules.

According to the information medium of the present invention, when a localized impact is applied from the reinforcing material side, the impact is distributed to the apexes of multiple protrusions, and by arranging the apexes of the protrusions so that they are not directly above the IC chip, it is possible to prevent the impact from being transmitted directly to the IC chip, thereby preventing damage to the IC chip.

1 is a schematic cross-sectional view of an embodiment of an IC module of the present invention; FIG. 2 is an explanatory diagram of a layer structure of one embodiment of an IC module of the present invention. 11A and 11B are plan views illustrating examples of the arrangement of protrusions. 4 is a schematic cross-sectional view showing a state when an impact is applied to the IC module of the present invention. FIG. FIG. 13 is a schematic cross-sectional view when an adhesive is used. 11 is a schematic cross-sectional view of another embodiment of an IC module of the present invention. FIG. 10A to 10C are schematic diagrams showing examples of convex portions having different shapes. 1 is a schematic cross-sectional view of one embodiment of an information medium of the present invention.

The following describes in detail the embodiments of the present invention with reference to the drawings. Note that the present invention is not limited to the embodiments described below. In addition, the embodiments described below have technically preferable limitations for implementing the invention, but these limitations are not essential requirements for the present invention.

Figure 1 is a schematic cross-sectional view of one embodiment of the IC module of the present invention. Figure 2 is an explanatory diagram of the layer structure. The IC module 1 is constructed by sequentially stacking an IC section 4, an intermediate layer 3, and a reinforcing material 2. The IC section 4 includes a molded section in which an IC chip 5 is embedded in a molding resin, a lead frame electrically connected to the IC chip 5, bumps, wire bonding, etc.

The intermediate layer 3 has a shape in which multiple convex portions 6 of the same height protrude toward the reinforcing material 2, and the tops of the convex portions 6a are in contact with the opposing member, which is the reinforcing material 2 in the example of FIG. 1. The contact points mentioned here are not limited to points in the mathematical sense, but also include area-like ones with a certain area. The shape of the convex portions 6 is not particularly limited, but may be a hemispherical protruding shape as shown in FIG. 2, and it is preferable that the tops have a smooth curved surface. The shape of the base of the convex portions 6 when viewed in a plane is circular if the convex portions 6 are hemispherical, but can also be any other shape such as a polygonal shape such as a rectangle, a triangle, or a hexagon, or an ellipse. In addition, the size of the base can be set appropriately as long as the height to the top is the same, and the bases of the convex portions 6 may all be the same size and shape, or may be a mixture of different sizes and shapes.

The arrangement of the protrusions 6 may be, but is not limited to, a staggered arrangement as shown in FIG. 3(a), a radial arrangement as shown in FIG. 3(b), a random arrangement as shown in FIG. 3(c), an arrangement in which different shapes and sizes are mixed as shown in FIG. 3(d), or a shape in which the walls of a honeycomb are protrusions as shown in FIG. 3(e). The protrusions 6 are provided in a position such that the contact point 6a is not located at the portion 5' directly above the IC chip 5 embedded in the IC portion 4.

Specific examples of the above arrangement are as follows:
Staggered: the pitch of the protrusions 6 is 1000 μm, the shape is hemispherical, and the protrusions 6 are linearly arranged with a half-pitch shift in the direction perpendicular to the arrangement direction (this can also be called a checkerboard pattern).
Random arrangement: The convex parts are hemispherical in shape and are arranged randomly in all directions. Radial arrangement: The convex parts are hemispherical in shape (aspect ratio 2:1), and the density changes linearly from sparse to dense as you move radially from the center.
etc.

The material for forming the intermediate layer 3 is preferably a material with a high elastic modulus, and examples thereof include, but are not limited to, metal, ceramic, carbon fiber, glass fiber, aramid fiber, epoxy, polyvinyl chloride, polyamide, cyanoacrylate, etc.

The reinforcing material 2 is layered on the convex portion 6 of the intermediate layer 3, and is in contact with the top of the convex portion 6 at the contact point 6a. In other words, the reinforcing material 2 and the intermediate layer 3 are not in contact over the entire surface, but are in partial contact at the portion facing the top of the convex portion 6, which is the contact point 6a. The reinforcing material 2 is provided to protect the IC chip from shocks such as dropping or external impacts, and therefore is preferably made of a material that has strength and elasticity, and examples of materials with a high elastic modulus include, but are not limited to, metals such as SUS, ceramics, carbon fiber, glass fiber, aramid fiber, epoxy, polyvinyl chloride, polyamide, cyanoacrylate, etc.

When a localized impact is applied to the IC module 1 configured as described above, for example from the reinforcing material 2 side, the reinforcing material 2 deforms at the site of the impact and in its vicinity as shown in Figure 4, and the stress caused by this deformation is transmitted to the intermediate layer 3. At that time, the stress is transmitted from the contact point 6a to the protrusion 6 and then to the IC part 4, but since the protrusion 6 is formed so that the contact point 6a is not directly above the IC chip 5, the impact transmitted to the protrusion 6 is unlikely to be transmitted to the IC chip 5, and damage to the IC chip 5 can be prevented.

The reinforcing material 2 and the intermediate layer 3 are typically bonded with an adhesive, but in this case, as shown in FIG. 5, the adhesive 7 may overflow not only near the contact point 6a but also into the gap other than the protruding portion 6 between the reinforcing material 2 and the intermediate layer 3, resulting in a state in which the gap is not filled but is partially filled. Even if the adhesive 7 is included in the gap in a manner that does not fill the gap as in IC module 1a, by using an adhesive 7 with a lower elastic modulus than the intermediate layer 3, the impact is propagated to the intermediate layer 3 with a higher elastic modulus, and the effect of making it difficult for the impact to be transmitted to the IC chip 5 can be similarly obtained.

Figure 6 is a schematic cross-sectional view of another embodiment of the IC module of the present invention. In this embodiment, the intermediate layer 3 has a convex portion 6 formed on the surface on the IC section 4 side. When an impact is applied to the reinforcing material 2 of an IC module 1b having such a shape, the deformation of the reinforcing material 2 is transmitted to the intermediate layer 3 and then to the convex portion 6. However, since the convex portion 6 is formed so that the contact point 6a is not directly above the IC chip 5, the impact transmitted from the convex portion 6 to the IC section 4 on the lower layer side to the IC chip 5 can be reduced, and damage to the IC chip 5 can be prevented.

Figure 7 is a schematic diagram showing an example of a different shape of the protrusion. The protrusion 6b has a through hole in the center and is in a half-loop (half-doughnut) shape. The presence of the through hole makes it easier for deformation to occur when an impact is applied, and makes it easier to absorb the impact.

It goes without saying that the convex portions as described above may be provided on both sides of the intermediate layer, i.e., on both the IC part side and the reinforcing material side.

Figure 8 is a schematic cross-sectional view of one form of the information medium of the present invention. This embodiment illustrates the form of an IC card 10. An inlet 8 carrying an IC module 1 of the present invention is inserted between front and back sheet materials 11a, 11b, filled with adhesive 9, and formed into a card shape. An electrode (not shown) that electrically connects to the IC module 1 and an antenna pattern 12 are formed on the inlet 8. When made into a card form, the effect of preventing damage to the IC chip as described above can be similarly obtained. The information medium of the present invention is not limited to the form of a card, and can take various forms such as a booklet such as a passport, an IC tag, or an IC label.

The reinforcing material and intermediate layer were attached to the side of the IC portion where the lead frame was provided, and a point-like impact was applied. Thereafter, a communication test was performed to check whether communication with the mounted IC chip was normal.
<Structure>
The IC module was mounted in the inlet by laser crimping.
<Ingredients>
Reinforcement: SUS304-H, square, 6 mm square Adhesive: Threebond, instant adhesive with brush 1743F
Intermediate layer: Glass cloth adhesive tape (Nitto Denko No. 973UL-S, thickness 130 μm)
Inlet: The molding resin of the Toyo Aluminum molded part is epoxy resin.

<Tests and their results>
(1) A glass cloth adhesive tape of the same shape and size as the molding resin is attached to the lead frame side of the IC module mounted in the inlet by laser crimping.
(2) Apply instant adhesive near the edge of the reinforcing material and attach it to the surface of the glass cloth.
(3) A point impact with a pressure of 1.96×10 ⁶ Pa was applied to the center of the IC chip on the normal line.
(4) After that, a communication test was conducted and it was confirmed that communication was performed without any problems and that the IC chip was not destroyed.

1 IC module 2 Reinforcement material 3 Intermediate layer 4 IC portion 5 IC chip 6, 6b Convex portion 6a Contact point 7 Adhesive 8 Inlet 9 Adhesive 10 Information medium (IC card)
11a, 11b...sheet material

Claims (7)

An IC module in which an IC part in which an IC chip is encapsulated, an intermediate layer, and a reinforcing material are laminated in this order,
the intermediate layer has a plurality of convex portions formed on at least one of the IC portion side and the reinforcing material side,
The top of the protrusion is in contact with an opposing member,
The IC module is characterized in that the top of the convex portion is formed at a position not directly above the IC chip. The IC module according to claim 1, characterized in that the protrusions are formed in a staggered arrangement pattern. The IC module according to claim 1, characterized in that the protrusions are formed in a radial arrangement pattern centered on the IC chip. The IC module according to claim 1, characterized in that the protrusions are formed in a random arrangement pattern. An IC module according to any one of claims 1 to 4, characterized in that the top portion is smoothly curved. An IC module according to any one of claims 1 to 5, characterized in that the gaps between the protrusions of the intermediate layer are filled with an adhesive having a lower elastic modulus than the material of the intermediate layer in a manner that does not fill the gaps. An information medium equipped with an IC module according to any one of claims 1 to 6.