JPH11345302A - Mounting method for ic chip, ic module, inlet and ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the manufacture cost without deteriorating the reliability of connection structure between a substrate and an IC chip in a mounting process of the IC chip. SOLUTION: An antenna substrate 2 has a resin sheet 20, connection patterns 23 constituted of a conductor foil formed on the resin sheet 20 and an unillustrated antenna pattern connected to the connection patterns 23. Bumps 41 are formed on an IC chip 3. A joining resin 40 is applied to the mounting face of the antenna substrate 2, the IC chip 3 is pressurized in a direction shown by an arrow in a drawing and it is heated. Thereby, the IC chip 3 and the antenna substrate 2 are fixed in a state where the bumps 41 are sunk into the connection patterns 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of mounting an IC chip on a substrate, an IC module having the IC chip,
The present invention relates to an inlet and an IC card having an IC module or an inlet.

[0002]

2. Description of the Related Art In recent years, as a card used for identifying an individual, an IC card having a built-in IC chip has attracted attention. Such an IC card has a connection terminal that can be electrically and mechanically connected to an external device.
Thus, data can be transmitted / received to / from the external device.

A contact type IC card having such connection terminals has a problem such as poor connection of the connection terminals, and requires a manual operation of inserting or mounting the IC card into a read / write device. In order to solve such a problem, a non-contact IC card capable of transmitting and receiving data to and from a read / write device without contact has been developed. The non-contact type IC card has an antenna inside the card, and data can be written into the card in a non-contact manner by electromagnetic waves or the like emitted from an external writing device.
Also, the recorded data can be read by an external device using an electromagnetic wave or the like.

[0004] The IC card having the connection terminals as described above includes an IC module in which an IC chip is mounted on a printed wiring board, and the non-contact IC card has the IC module and an antenna substrate connected. It has a so-called inlet. In addition, non-contact IC
In some cards, an inlet in which an IC chip is mounted on a printed wiring board on which a spiral antenna pattern and a wiring pattern on which the IC chip is mounted is formed.

[0005]

As a method of mounting an IC chip on a printed wiring board in such an IC module or an inlet, a wire bonding method, a flip chip method, or the like is used. When mounting IC chips by the flip-chip method, which is currently the mainstream, it is required that the mounting surface of the IC chip has no irregularities in order to improve the reliability of the connection between the IC chip and the printed wiring board. Will be done. For this reason, conventionally, when gold is used as a bump, a method of forming a bump having a uniform height by plating is used, and when using a stud bump method, the bump height is accurately adjusted after the bump is formed. A method called leveling is used. Further, in order to improve the reliability of bonding, a method is also used in which, on the printed wiring board side, nickel plating is applied to copper foil and gold plating is applied to smooth the mounting surface.

[0006] When the IC chip is mounted by the flip-chip method as described above, it is necessary to perform steps of accurately adjusting the height of the bumps of the IC chip and smoothing the mounting surface of the printed wiring board. Was increasing.

The present invention has been made in view of the above circumstances, and an IC chip mounting method capable of reducing the manufacturing cost without reducing the reliability of the connection structure between the substrate and the IC chip. And an IC module, an inlet, and an IC card including an IC chip mounted by this method.

[0008]

In order to solve the above problems, an IC chip mounting method according to the present invention is a method of mounting an IC chip having a bump portion on a substrate having a wiring pattern portion, wherein The bump portion of the chip,
The bump portion and the wiring pattern portion may be connected by being inserted into the wiring pattern portion of the substrate.

According to this method, the bump portion of the IC chip is immersed in the wiring pattern portion of the substrate and connected, thereby irrespective of a slight variation in the height of the bump portion and irregularities of the wiring pattern. Thus, the reliability of the connection structure can be improved. Therefore, a step of adjusting the height of the bump portion, a step of smoothing the wiring pattern, and the like are not required, and the manufacturing cost can be reduced.

The method of mounting an IC chip according to a second aspect of the present invention is the method of mounting an IC chip according to the first aspect, further comprising a step of fixing the IC chip and the substrate with an insulating resin. Features. According to this method, since the bump portion is recessed into the wiring pattern portion, that is, the bump portion and the wiring pattern portion are in direct contact, conductive resin or the like is used to fix the IC chip and the substrate. No need to use. Therefore, the manufacturing cost can be further reduced by fixing the IC chip and the substrate using the insulating resin while maintaining the electrical connection between the bump portion and the wiring pattern.

According to a third aspect of the present invention, there is provided an IC module including a substrate having a wiring pattern portion and a bump portion, wherein the IC module mounted on the substrate by the method according to the first or second aspect. It is characterized by having.
An IC module according to a fourth aspect is the IC module according to the third aspect, wherein the wiring pattern portion is made of aluminum.

According to a fifth aspect of the present invention, an inlet has a substrate having a wiring pattern portion including an antenna and a bump portion, and is mounted on the substrate by the method according to the first or second aspect. And an IC chip. The inlet according to claim 6 is the inlet according to claim 5, wherein the wiring pattern portion is made of aluminum.

According to a seventh aspect of the present invention, there is provided an IC card including the IC module according to the third or fourth aspect, and a card base in which the IC module is embedded. According to an eighth aspect of the present invention, there is provided an IC card including the inlet according to the fifth or sixth aspect and a card base into which the inlet is inserted.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. A. First embodiment A-1. Configuration First, FIG. 1 shows an inlet 1 according to a first embodiment of the present invention.
Is shown. As shown in FIG. 1, the inlet 1 includes an antenna substrate 2 and an IC chip 3 mounted on the antenna substrate 2. Here, FIG. 2 shows the antenna substrate 2. As shown in FIG. 2, the antenna substrate 2 is formed by forming an antenna pattern 21 in a spiral shape on a film-shaped resin sheet 20.

As the resin sheet 20, an insulating resin can be used. For example, glass epoxy resin used for ordinary printed wiring boards, PI (polyimide) or PET (polyethylene terephthalate) used for flexible printed wiring boards, or the like can be used. Etc. can be used. In addition, resins such as PVC (polyvinyl chloride) and ABS (acrylonitrile butadiene styrene), or resins obtained by mixing ABS resin with PC (polycarbonate), PET and PA (polyamide), PP (polypropylene), Any material such as PEN (polyethylene naphthalate) and PPS (polyphenylene sulfide) may be used as long as it can be formed into a sheet. In addition, inorganic materials such as titanium oxide, calcium carbonate, and glass fiber may be mixed with these resins.

At both ends of the antenna pattern 21, connection patterns (wiring pattern portions) 23 to be joined to the IC chip 3 are formed. The antenna pattern 21 and the connection pattern 23 may be a conductor, but in this embodiment, an aluminum foil is used. This is because aluminum foil is superior in workability and cost as compared with copper, and its electrical properties are comparable to those of copper.

When the antenna pattern 21 is formed on both sides of the antenna substrate 2, the antenna pattern 21 formed on one surface of the resin sheet 20 is electrically connected to the antenna pattern 21 formed on the other surface. There is a need. In such a case, pressure is applied to a portion of the antenna substrate 2 to be conducted, and as shown in FIG.
The resin sheet 20 and the antenna pattern 21 are deformed. Thereby, the antenna patterns 21 formed on the upper surface and the lower surface of the resin sheet 20 are joined and can be conducted. Further, as shown in FIG. 3B, the resin sheet 20 and the antenna pattern 21 may be deformed so as to conduct, so that the antenna patterns 21 formed on the respective surfaces of the resin sheet 20 are joined. Then, the resin sheet 20 and the antenna pattern 21 may be deformed. Here, as a method of deforming the resin sheet 20 and the antenna pattern 21, a simple pressurization method may be used, or a method in which the resin sheet 20 and the antenna pattern 21 are heated to a temperature at which they are easily deformed and pressurized. There is also a method of deforming at low temperature by applying ultrasonic waves. However, when the antenna substrate 2 is deformed in this way, it is preferable to use a resin sheet 20 having a small thickness and being easily deformed. For example, a thermoplastic resin such as PP or PET is desirable, and the thickness is preferably 100 μm or less, and 50 μm or less for stable processing.

In the inlet 1 according to this embodiment, the mounting of the IC chip 3 on the antenna substrate 2 uses a flip chip bonding method. Here, FIG. 4 shows a joint portion between the antenna substrate 2 and the IC chip 3 in the inlet 1. As shown in the figure, a bonding resin 40 is applied to a mounting portion of the antenna substrate 2 on which the IC chip 3 is mounted, and the antenna substrate 2 and the IC chip 3 are fixed by curing the bonding resin 40. ing. A bump 41 is formed on the lower surface of the IC chip 3 by a plating method, a stud bump method, or the like, and the bump 41 is joined to the connection pattern 23 of the antenna substrate 2 in a state where the bump 41 is embedded therein. Here, the thickness ε of the connection pattern 23 and the thickness α of the bump 41 are determined by the main body of the IC chip 3 and the resin sheet 2.
It may be determined according to the interval δ from 0. That is, the bumps 41 and the connection patterns 23 may be formed so that α + ε is larger than δ.

In this embodiment, as described above, the bump 4
Since 1 is embedded in the connection pattern 23, that is, is directly joined, the joining resin 40 is not limited to the conductive resin, and an inexpensive insulating resin can be used. The resin to be used may be arbitrarily determined according to the required conditions such as the time to be applied, the adhesive strength, and the heat resistance. For example, an epoxy resin, a silicone resin, an acrylic resin, a phenol resin, a polyimide resin, a polyphenylene sulfide resin, or the like can be used.
Further, those obtained by adding a filler to these resins may be used.

The joining resin 40 is not limited to the above-mentioned insulating resin, but may be a resin having conductivity such as ACF (anisotropic conductive film). ACF
The word “is” means that conductive particles are dispersed in an insulating resin processed into a sheet shape, but it is also possible to use a liquid material other than the processed into a sheet shape. When a highly transparent resin sheet 20 is used, an ultraviolet-curable resin may be used as the joining resin 40. In this case, the bonding resin 40 can be cured by irradiating ultraviolet rays from the back side of the resin sheet 20.

A-2. Manufacturing Method Next, an example of a method for manufacturing an IC card having the above-described inlet will be described. First, the antenna pattern 2 and the connection pattern 23 made of aluminum foil shown in FIG. 2 are formed on the resin sheet 20 by an etching method or the like, and the antenna substrate 2 is manufactured. On the other hand, IC chip 3
As shown in FIG. 5, bumps 41 are formed on the bonding pads by a stud bump method or a plating method.

Next, a method of mounting the IC chip 3 on the antenna substrate 2 manufactured as described above, that is, a method of mounting the IC chip according to the present invention will be described. As shown in FIG. 5, a bonding resin 40 is applied to a portion of the antenna substrate 2 where the IC chip 3 is to be mounted. Then, as shown in FIG. 6, with the IC chip 3 placed on the antenna substrate 2,
The bumps 41 are sunk into the connection pattern 23 by heating and pressing in the direction indicated by the arrow in the figure. In this case, I
The pressure applied to the C chip 3 is 200 gf / cm ² -5 k
It is preferably about gf / cm ² .

Thereafter, the IC chip 3 and the antenna substrate 2 are fixed by curing the bonding resin 40.
As described above, the method of curing the joining resin 40 differs depending on the type of the resin used as the joining resin 40, and is cured by heating or irradiating ultraviolet rays. For example, in the case of a thermosetting resin, some of the resins used cure in about 5 seconds, others require about 100 seconds, and the curing temperature is 1
Some require only about 00 ° C, while others require 200 ° C or higher. Therefore, depending on the resin used, high temperature and long time may be required for curing. In this case, after the resin is cured at a low temperature to the extent that the IC chip 3 does not come off, take time in a constant temperature bath. By curing by heating, an increase in cost can be suppressed. When a sheet-like ACF is used as the joining resin 40,
As shown in FIG. 7, a bonding resin 40 is provided on the antenna substrate 2.
After the ACF is temporarily attached, the IC chip 3 is mounted on the antenna substrate 2 by pressurizing and heating.

As described above, after the joining resin 40 is cured by a curing method suitable for the joining resin 40 to be used, the periphery of the IC chip 3 is sealed with the resin 70 if necessary, whereby The inlet 1 shown in FIG.

Then, as shown in FIG. 9, the inlet 1 is sandwiched between the adhesive layer 71 and the surface layer 7 and the adhesive layer 73, laminated, and then punched into a predetermined card shape. Thus, the inlet 1, that is, a non-contact type IC card 90 equipped with an antenna and an IC chip as shown in FIG. 10 is manufactured.

A-3. Effect In the present embodiment, the IC chip 3 is heated and
Since the bump 41 is pressed into the connection pattern 23 by applying pressure, even when the connection pattern 23 has an oxide film,
The bump 41 and the connection pattern 23 are securely bonded by breaking through this oxide film. That is, there is no need to perform a step of processing the oxide film of the connection pattern 23, and the manufacturing cost can be reduced. In addition, since the bump 41 is deformed when it is embedded in the connection pattern 23, the shape of the bump 41 and the bump 4
The reliability of the connection structure between the bumps 41 and the connection patterns 23 can be maintained without any problem even if the height of 1 is slightly varied. Therefore, there is no need to perform a step of accurately adjusting the height of the bumps, and the manufacturing cost can be reduced. Further, even when an etching resist used when forming the connection pattern 23 by the etching method or an oxidation preventing film is attached to the connection pattern 23, the bump 41 and the connection pattern 23 can be reliably connected. is there. Also, the joining resin 40
It is not necessary to use a conductive material, and an inexpensive insulating resin can be used, so that the manufacturing cost is reduced.

B. Second Embodiment FIG. 11 shows an IC module 80 according to a second embodiment of the present invention. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. As shown in FIG.
Has a printed wiring board (substrate) 81 and an IC chip 3.

The printed wiring board 81 includes a resin sheet 82. On the surface of the resin sheet 82, a connection pattern (wiring pattern portion) 83 made of a conductor such as aluminum foil is formed by an etching method or the like. I have. As the material of the resin sheet 82, the same material as the resin sheet 20 in the first embodiment can be used.

IC chip 3 on printed wiring board 81
A bonding resin 40 is applied to the mounting surface of the IC chip 3, and the IC chip 3 and the printed wiring board 81 are fixed by curing the bonding resin 40. When the IC chip 3 is mounted, it is heated and pressed as in the first embodiment, so that the bump 41 is joined to the connection pattern 83 in a state of being sunk.

The IC module 80 according to the present embodiment also
Like the inlet 1 according to the first embodiment, the bump 41 is recessed into the connection pattern 83 and joined, so that
The manufacturing cost can be reduced without deteriorating the reliability of the connection structure between the C chip 3 and the printed wiring board 81.

The IC module 8 according to the present embodiment
0 may be connected to the antenna substrate 2 in the first embodiment by soldering or the like to form an inlet. As shown in FIG. 12, an external connection terminal 86 is provided on the surface of the printed wiring board 81 opposite to the surface on which the IC chip 3 is mounted.
By embedding the “0” in the recess 84 and the card base 85, a contact-type IC card may be manufactured.

[0032]

Next, an example of actually producing an IC card according to the present invention will be described. A. Example 1 First, a PET sheet having a thickness of 25 μm was used as the resin sheet 20. An aluminum foil having a thickness of 30 μm was attached to this PET sheet with a urethane-based adhesive. Then, after applying an etching resist to the resin sheet 20 by a gravure printing method, an antenna pattern 21 and a connection pattern 23 were formed by an etching method. In this embodiment, since the antenna patterns 21 were formed on both surfaces of the resin sheet 20, pressure was applied to the resin sheets 20 to make the respective antenna patterns 21 formed on both surfaces of the resin sheet 20 conductive. Thus, the antenna substrate 2 shown in FIG. 2 was manufactured.

On the other hand, an IC chip 3 having an outer shape of 3 mm square was used, and gold bumps were formed on the bonding pads of the IC chip 3 as bumps 41 by a stud bump method. Here, the bump 41 is formed on a 110 μm square pad.
No leveling to make bump height uniform, diameter 60
Approximately 80 μm and a height of approximately 65 μm were used.

As a method for mounting the IC chip 3 on the antenna substrate 2, a flip chip method is used.
0 and apply thermosetting epoxy resin, and IC chip 3
Was aligned on the antenna substrate 2. After this, IC
While mounting the chip 3, a pressure of 1 kgf / cm ² was applied to the IC chip 3, and the mounting head was heated to 180 ° C. Here, a ceramic head was used as the mounting head, and heating was performed by a pulse heating method.
In this state, pressurizing and heating are performed for 30 seconds to form the bonding resin 4.
0 was cured. Then, an ultraviolet curable resin was applied to the periphery of the IC chip 3 as the resin 70, and then irradiated with ultraviolet rays to seal the periphery of the IC chip 3 with a resin, thereby producing the inlet 1 shown in FIG.

Thereafter, a surface layer 72 which is a PET sheet having a thickness of 125 μm and an adhesive layer 71 having a thickness of 300 μm,
After laminating with the inlet 1 interposed between the adhesive layer 73 having a thickness of 300 μm and cutting it into a predetermined card shape.
Thus, an IC card 90 having a highly reliable connection structure between the IC chip 3 and the antenna substrate 2 was obtained.

B. Example 2 First, a PET sheet having a thickness of 38 μm was used as the resin sheet 20. An aluminum foil having a thickness of 35 μm was attached to this PET sheet using a urethane-based adhesive. Then, after applying an etching resist to the resin sheet 20 by a gravure printing method, an antenna pattern 21 and a connection pattern 23 were formed by an etching method. In this embodiment, since the antenna patterns 21 were formed on both surfaces of the resin sheet 20, pressure was applied to the resin sheets 20 to make the respective antenna patterns 21 formed on both surfaces of the resin sheet 20 conductive. Thus, the antenna substrate 2 shown in FIG. 2 was manufactured.

On the other hand, an IC chip 3 having an outer shape of 5 mm square was used, and a gold bump was formed as a bump 41 on a bonding pad of the IC chip 3 by a plating method. Here, the bump 41 has a diameter of about 60 to 80 μm and a height of about 40 μm on a 110 μm square pad without performing leveling or the like.
The thing of about μm was used.

As a method of mounting the IC chip 3 on the antenna substrate 2, a flip chip method is used. First, as shown in FIG. 25 μm ACF 8
The IC chip 3 was temporarily attached at 0 ° C., and the IC chip 3 was aligned on the antenna substrate 2. Thereafter, the IC chip 3 was mounted, a pressure of 5 kgf / cm ² was applied to the IC chip 3, and the mounting head was heated to 180 ° C. In this state, pressing and heating were performed for 15 seconds to cure the bonding resin 40.
Here, as in Example 1, heating was performed by a pulse heating method using a ceramic mounting head. Then, a thermosetting resin was applied as a resin 70 around the IC chip 3, and then heated to seal the resin around the IC chip 3, thereby producing the inlet 1.

Thereafter, a surface layer 72 which is a PET sheet having a thickness of 125 μm and an adhesive layer 71 having a thickness of 300 μm,
After laminating with the inlet 1 interposed between the adhesive layer 73 having a thickness of 300 μm and cutting it into a predetermined card shape.
Thus, an IC card having a highly reliable connection structure between the IC chip 3 and the antenna substrate 2 was obtained.

[0040]

As described above, according to the present invention,
Since the bump portion of the IC chip is connected to the wiring pattern portion of the substrate by being sunk into the wiring pattern portion, a process of making the height of the bump portion uniform and a process of smoothing the wiring pattern portion are unnecessary. Therefore, it is possible to reduce the manufacturing cost without lowering the reliability of the connection structure between the substrate and the IC chip.

[Brief description of the drawings]

FIG. 1 is a plan view showing an inlet according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an antenna substrate which is a component of the inlet.

FIG. 3A is a diagram for explaining an example of a method of conducting an antenna pattern formed on both surfaces of the antenna substrate, and FIG. 3B is a diagram illustrating another example of a method of conducting the antenna pattern. FIG.

FIG. 4 is a cross-sectional view showing a mounting portion of the antenna substrate on which the IC chip is mounted in the inlet.

FIG. 5 is a view for explaining a method of manufacturing an IC card having the inlet.

FIG. 6 is a view for explaining a method of manufacturing an IC card having the inlet.

FIG. 7 is a view for explaining another example of a method for manufacturing an IC card having the inlet.

FIG. 8 is a view for explaining a method of manufacturing an IC card having the inlet.

FIG. 9 is a view for explaining a method of manufacturing an IC card having the inlet.

FIG. 10 is a perspective view showing an IC card including the inlet.

FIG. 11 is a sectional view showing an IC module according to a second embodiment of the present invention.

FIG. 12 is a sectional view showing a configuration of an IC card including the IC module.

[Explanation of symbols]

1. Inlet, 2. Antenna substrate (substrate), 3. IC
Chip, 20: resin sheet, 21: antenna pattern,
23 connection pattern (wiring pattern portion), 40 bonding resin, 41 bump, 80 IC module, 81 printed wiring board (substrate), 82 resin sheet, 83 connection pattern (wiring pattern portion), 90 … IC card

Claims (8)

[Claims] 1. A method of mounting an IC chip having a bump portion on a substrate having a wiring pattern portion, wherein the bump portion of the IC chip is embedded in the wiring pattern portion of the substrate. A method for mounting an IC chip, comprising connecting a bump portion and the wiring pattern portion. 2. The method according to claim 1, further comprising the step of fixing the IC chip and the substrate with an insulating resin. 3. An IC module comprising: a substrate having a wiring pattern portion; and an IC chip having a bump portion and mounted on the substrate by the method according to claim 1 or 2. . 4. The IC module according to claim 3, wherein said wiring pattern portion is made of aluminum. 5. A substrate having a wiring pattern portion including an antenna, and an IC chip having a bump portion and mounted on the substrate by the method according to claim 1 or 2. And inlet. 6. The inlet according to claim 5, wherein the wiring pattern portion is made of aluminum. 7. An IC card, comprising: the IC module according to claim 3; and a card base in which the IC module is embedded. 8. An IC card comprising: the inlet according to claim 5; and a card base into which the inlet is inserted.