JP2003317058A - Ic chip mounted body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide at low cost an IC chip mounted body which is more reliable against an external force than a conventional IC chip mounted body having a reinforcing member. <P>SOLUTION: The IC chip mounted body which has an inlet sheet 1 mounted with a bare IC chip 6 of at least ≥300 μm in thickness and a coating layer 3a and does not have a reinforcing member for bare IC chip protection and is of 700 to 900 μm in overall thickness is sufficiently thick in spite of the bar IC chip, so the IC chip mounted body has strength equal to or more than that of the IC card using the reinforcing member even in a spot pressure strength test and a shock test. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The IC chip mounting body of the present invention is a contact type IC card used for bank cards, point cards, etc., a ticket, a telephone card,
The present invention relates to a so-called non-contact type IC card which is used as a luggage tag or the like for performing data communication and the like by external radio waves, and a so-called combination type IC card having both contact type and non-contact type functions.

These IC chip mounting bodies are also called so-called data carriers, and are commonly called IC cards, but they are not limited to those in the form of cards, but are enclosed in sheets or containers that are attached to objects. It also includes various types of carriers such as tags and wristwatch types. Also in this specification, the IC chip mounting body is used as including an IC card or a form other than the card form.

[0003]

2. Description of the Related Art In recent years, small electronic devices having an IC chip as a new information recording medium on a commuter pass used for personal information management, physical distribution management, commuting to school, etc. have become popular. In particular, a card-type large-capacity variable information recording medium called an IC card, which is convenient for carrying, is beginning to spread widely. IC cards are roughly classified into three types: contact type, non-contact type, and combination type having both functions. The contact-type IC card is provided with a metal terminal for data exchange electrically connected to the IC chip on the surface of the card, and data is exchanged with an external reader through the terminal. Is. Currently, the disposable type is widely distributed as a telephone card in Europe and the like, and an experiment using a rewritable type of information as a money card is being conducted in each country. In particular, it is attracting attention as a card used in financial relations.

On the other hand, the non-contact type IC card exchanges data by radio waves in a non-contact manner, so that, for example, a conventional ticket, a commuter ticket, or the like, which is replaced with a ticket having a magnetic recording layer provided on one side, is used. It is attracting attention as a medium. In particular,
It is expected that convenience will be greatly improved because data can be exchanged even from a passport or bag without having to take out the ticket one by one when passing through the ticket gate. Also in the field of logistics, RFID (Radio Frequent) is used to replace bar codes and magnetic recording and exchange data with mobile objects by radio waves.
I called "ncy Identification" tag
Management by C carriers is becoming mainstream.

There is a demand for a thin IC chip package represented by such an IC card in order to improve portability of the card, and at present, a thickness of 1 mm or less is becoming common. . Under such circumstances, it is a major issue in handling them to protect the bare IC chip, which is a component having the weakest mechanical strength, from external force such as pressing, bending, and impact. For bare IC chips that are vulnerable to such external forces, bare ICs mounted and fixed by face-down method on the inlet sheet
For the purpose of protecting the chip, a metal reinforcing member is attached to the silicon side surface of the bare IC chip (on the side of the constituent material such as silicon,
A great number of methods have been introduced to prepare for the Si side for short and the circuit surface side (the side on which the circuits of the chip are formed, and the inlet sheet side when viewed from the IC chip mounting body). Also, bare ICs that are vulnerable in this way
It is also often introduced to use a packaged IC that is packaged by a method such as molding without directly using the chip.

[0006]

However, in the conventional method, since the reinforcing member is provided at least on the silicon side surface of the IC chip, the thickness of the IC chip mounting body is increased, and the work steps such as component parts and bonding are increased. It is inevitable to go. An object of the present invention is to solve the above-mentioned problems, as compared with a conventional IC chip mounting body having a reinforcing member,
It is to provide a highly reliable IC chip mounting body that is resistant to external force at low cost.

[0007]

An IC chip mounting body according to the present invention is a bare IC having a thickness of at least 300 μm or more.
An IC chip mounting body having an inlet sheet having a chip mounted thereon and a coating layer and having no reinforcing member for protecting a bare IC chip and having a total thickness of 700 to 900 μm. Further, the thickness from the silicon side surface of the bare IC chip to the surface of the mounting body is preferably 200 μm or less from the viewpoint of improving the strength. Further, it is preferable for the tensile strength of the inlet sheet to be 100 MPa or more for improving the strength. It is also preferable for ensuring strength that the thickness of the circuit provided on the inlet sheet at least in the vicinity of the connection portion of the bare IC chip is 50 μm or less.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventor has tried to protect a bare IC chip by using a reinforcing member while verifying the prior art. It was found that the integration of the bare IC chip and the reinforcing member by adhesion is one of the important factors, and the strength and hardness of the reinforcing member are also important factors. Thus, considering the ultimate integration of the chip and the reinforcing member by adhesion, and considering that a reinforcing member having a high hardness is preferable, it is considered that silicon (silicon), which is the material of the bare IC chip itself, may be used. The bare IC chip, which has been thinly processed along with the thinning of IC cards and the like, has been tried by using a large thickness without processing the bare IC chip. As a result, depending on the conditions, an IC chip package having a strength equal to or higher than that of the IC chip package using the reinforcing member has been manufactured. An IC card will be described below as a typical example of an IC chip package. There is a concern that thickening the bare IC chip may cause the following problems. That is, the edge angle of the chip is likely to be chipped. The chip is cleaved at the crystal plane and becomes thin and easily cracked. Since the entire thickness of the card is limited, the card material such as the coating layer covering the chip becomes relatively thin and the impact strength becomes weak. It is susceptible to stress due to bending, and is prone to cracking. Chip marks are likely to appear on the card surface. Problems such as these were expected. However, as a result of the trial, the thickness is at least 300.
The total thickness is 700 to 900 with the inlet sheet and the coating layer with bare IC chips of μm or more attached.
It was found that in the case of the IC chip mounting body of μm, very good mechanical strength was obtained without the reinforcing member for protecting the bare IC chip, and the above problems did not occur.

That is, the following findings were obtained for each of the above items. The edge of the tip was never applied. Such a cleavage phenomenon did not occur. Since it is assumed that the thickness of the IC chip mounting body (card) is limited to a certain value, if the thickness of the bare IC chip becomes thicker, the front and back side coating layers having the function of protecting the chip, the back side coating layer and those layers and the inlet are provided. It was thought that the adhesive layer for adhering the sheet would be relatively thin, so that it would be weak against so-called impact force, but such a result was not obtained. It was thought that other base materials, etc. that also act as protection under the stress due to bending would become thin, so that it would become weak, but such a result was not obtained. For the same reason as the surface of the bare IC chip on the silicon side, etc., the distance from the surface side of the mounting body becomes small,
It was imagined that those molds would easily appear as chip marks, but such marks were not. In the end, contrary to expectations, a highly reliable non-contact IC card with excellent mechanical strength and without the above-mentioned drawbacks was obtained. Specifically, the following tests regarding strength and the like were performed, and the respective results were obtained.

1. Push-in test (point strength test) FIG. 9 shows a cross-sectional view of the push-in test. A molded IC card 20 is placed on a silicone rubber 16 having a hardness of 50, and a metal ball 15 made of SUS304 having a tip diameter of 10 mm is placed directly above the bare IC chip 6.
It measures the force at which communication is lost by pushing in at a speed of 1 mm / min. General application conditions (test environment, etc.) in the test conform to JIS X 6305. The judgment conditions are specified as follows. ○: 35 N or more, Δ: 25 to 35 N, ×: 25 N or less 2. Metal ball drop test (impact test) A molded card is placed on a metal plate, and a SUS304 metal ball with a mass of 10 g is dropped on the chip part. , Measure the height at which communication is lost. General application conditions (test environment, etc.) in the test conform to JIS X 6305. The judgment conditions are specified as follows. ○: 10 cm or more, Δ: 5 to 10 cm, ×: 5 cm or less

3. Bending test Tested by the method specified in ISO / IEC 10536-1. ○ when communication is possible, × when communication is not possible. 4. Torsion test Tested by the method specified in ISO / IEC 10536-1. ○ when communication is possible, × when communication is not possible. 5. Chip bending strength Fix one end of the card to the aluminum plate with a clamp so that the chip part of the card comes to the corner position of the aluminum plate with a thickness of 20 mm, and bend it 90 degrees by hand perpendicularly to the longitudinal direction of the card. Hold for seconds, and then return the card to a flat state. ○ If communication is possible, × if not. General application conditions (test environment, etc.) in the test conform to JIS X 6305.

[0012] Good results were obtained by the above-described test method, and such a thick bare IC chip had unexpectedly strong strength in the tests in which the reinforcing member is considered to have a great influence among the above-mentioned tests. The reason for ensuring the above was considered as follows. 1. Indentation test (point pressure strength test) The compression strength of silicon, which is an IC chip material, is originally high,
When the thickness was about 300 μm or more, the point pressure strength of the chip on the inlet sheet where the chip was exposed was very strong. This state is shown in FIG. Figure 8
FIG. 6 is a cross-sectional view showing a state in which a point pressure strength test is performed with the bare IC chip exposed. The bear IC chip 6 is attached to the inlet sheet 1 having an antenna circuit formed thereon via an ACF (anisotropic conductive adhesive) 8. The inlet sheet 1 is placed on the silicone rubber 16, and the tip diameter is 10 m just above the exposed bare IC chip 6.
Apply a metal ball 15 made of SUS304 of 1 mm / mi.
It was pushed in at a speed of n and the force to lose communication was measured. Next, when a point pressure strength test is similarly performed on an IC card formed into a card of JIS standard (760 μm) using this inlet sheet without using a reinforcing member, the point pressure strength is lowered. There was found. It is conceivable that this is because the pressure applied to the chip was eliminated only by the compressive force applied to the chip in the exposed state.

FIG. 9 shows a state in which a point pressure strength test is performed on this IC card. FIG. 9 shows a comparatively thin bare IC chip which has been conventionally used without using a reinforcing member.
It is sectional drawing which shows the state which performs a point pressure strength test, after finishing into a card. Adhesive layers 10 on both sides of the inlet sheet 1
The coating layers 3a and 3b are arranged via a and 10b.
Since the metal spheres 15 are pressed from above the coating layer 3a, the metal spheres 15 have a flexible coating layer 3a and an adhesive layer 10.
As it can be seen from the figure, the pressure that was transmitted by point contact in FIG. 8 is transmitted by surface contact between the metal ball and the card in FIG. Therefore, a force in the direction of arrow X in the drawing is applied not only near the contact point of the metal ball but also near the circuit side surface 6a of the bare IC chip, that is, a non-uniform force is applied to the entire chip, and finally the circuit side of the chip is applied. It is presumed that cracks 17 etc. will occur and the function will be destroyed.

As the thickness of the chip increases, the strength of the chip naturally increases, but the thickness of the chip up to the surface of the card on the silicon side, that is, the thickness of the card forming material (intermediate layer such as coating layer and adhesive layer). It is considered that as the thickness becomes smaller, the contact area with the metal ball becomes smaller, the state becomes closer to the point contact state, and the chip becomes a structure close to the bare state, so that the strain is reduced and the strength is increased. That is, the thickness is preferably 200 μm or less, more preferably 100 μm or less. If it is made too thin, there are problems such as weakness in an impact strength test to be described later and that the IC chip is easily visible through the outer surface of the card. Therefore, the minimum thickness is about 30 μm. In recent years, bare IC chips have become a large chip with a CPU and a low-priced small chip of 2 mm square or less shown in the embodiments of the present invention. It is considered that the smaller the chip becomes about 2 mm square or less, the smaller the strain applied to the chip becomes, and thus the method using no reinforcing member as in the present invention becomes advantageous. In particular, if these low-priced small chips cost too much for reinforcement, the IC
There is a problem that the price of products such as cards becomes high and it is difficult for them to spread. Therefore, the method of the present invention is extremely advantageous in that it can achieve both cost and performance.

Since the electric circuit pattern is repeatedly formed on the surface of the chip on the circuit side by etching, it is presumed that there are many micro scratches. When a load is applied from the silicon side surface 6b, the micro scratches spread in the direction,
It is considered that the chip is more likely to be damaged as compared with the case where a load is applied from the circuit side surface 6a, which proves that the strain damages the chip. Furthermore, when reinforcing the chip with a metal plate, it was found that the strength is higher when the size of the metal plate is sufficiently larger than the size of the chip. Considering this, it is considered that a larger metal plate disperses the force and lessens the strain given to the chip, and it is the same as the case where the thickness of the silicon side of the chip to the card surface is thinned as described above. be able to.

The tensile strength of the base sheet used for the inlet sheet used in the present invention is JIS C231.
The tensile strength described in 8 is preferably 100 MPa or more. The inlet sheet is the circuit side 6a of the chip
When it receives a force from the silicon surface of the chip, the tensile strength of the film of the inlet sheet is 1 in order to reduce the force that the circuit side surface 6b opens.
When it is at least 00 MPa, the effect of preventing breakage of the chip is further enhanced. The antenna circuit connected to the chip used in the present invention is preferably 50 μm or less. That is, more specifically, it is preferable that the thickness of at least the connection portion of the bare IC chip of the circuit is 50 μm or less. A part of the chip overlaps the circuit, but there is a part where the circuit does not overlap, and naturally the chip is distorted when pressure is applied from the silicon side surface. Antenna circuit is 50 μm
If it is thinner, resin (ACF,
(ACP, NCP, etc.) is provided between them, so that the strain can be relaxed to some extent. However, in the case where the strength is increased without reinforcement as in the present invention, this portion can be thinned. It is extremely effective. It goes without saying that there is a limit because if the circuit is made too thin, the performance as an antenna circuit cannot be ensured.

In a more preferred form of the present invention, the strength of the chip itself is improved by increasing the thickness of the chip and the base material (more accurately, the thickness of the silicon side surface of the chip to the surface of the card) is made thinner. Due to the synergistic effect of adopting a structure in which the bare IC chip is less likely to be distorted, it is effective in increasing the chip strength of the IC card.

2. Metal Ball Drop Test (Impact Test) When the thickness of the bare IC chip in the card is changed and the impact test described above is performed, the strength increases substantially in proportion to the thickness of the chip. In this case, a bare chip having the same thickness as the one obtained by adhering a metal plate to a chip with a resin to reinforce the bare chip has a higher strength. Aside from the case where the chip itself became thin enough to be flexible, the impact force applied to the chip reinforced by the metal plate was unexpectedly unclear as to the effect of reinforcing the metal plate. It can be inferred that the thickness of the tip is the main factor of impact strength. After all, since silicon itself is materially strong, it is considered that the use of a thick tip as in the present invention results in an advantage in improving impact strength as compared with the case of using a reinforcing member.

The present invention can be used in any of contact type, non-contact type and combination type IC cards. Among them, a non-contact type IC card suitable for using the present invention will be described. First, the process from the circuit substrate to the formation of the inlet will be described.

1. Processes from the circuit substrate to the formation of the inlet will be described below with reference to the drawings. A plan view and a sectional view of the circuit substrate are shown in FIGS. 1 and 2, respectively. FIG. 1 is a plan view of a circuit substrate used in the present invention, and FIG.
It is an A'sectional view. The metal foil 2 as a thin metal layer is bonded to the inlet sheet 1 generally using an adhesive to form a circuit substrate. A pattern of the protective film 5 is formed on the metal foil 2 on the circuit substrate. Metal foil 2
The portion where the protective film 5 is not applied is removed by etching or the like to form a circuit pattern including the antenna. In some cases, the metal foil may be joined to the inlet sheet without using an adhesive by a method described later.

3 and 4 are respectively a plan view and a cross-sectional view of a circuit substrate on which the metal foil 2 is patterned using the protective film 5 as a mask to form the circuit pattern 2b. FIG. 3 is a plan view of the circuit substrate after etching, and FIG. 4 is a sectional view taken along the line AA ′. When the circuit substrate after the circuit pattern 2b is formed by etching or the like is referred to as the circuit substrate before etching, it is referred to as an "etched circuit substrate". Here, an example in which the circuit patterns 2b are formed on both surfaces of the inlet sheet 1 is shown. Through holes 4 are formed in the inlet sheet 1 in order to connect the circuit patterns 2b, 2b on both sides of the support to each other, and the circuit patterns 2b, 2b on both sides of the support are connected to each other through the through holes 4. Has been done.

A sheet in which electronic parts such as an IC chip, a capacitor and an antenna are mounted on this etching circuit substrate is called an "inlet". This inlet is shown in FIGS. FIG. 5 is a plan view of the inlet, and FIG. 6 is a sectional view taken along line BB ′ of FIG. FIG. 7 shows I of the circle portion shown in FIG.
It is an expanded sectional view in the Example from which a C mounting part differs.
In FIG. 7, the bare IC chip 6 is in a state in which the gold bumps 7 are exposed, and the state in which the bumps 7 are connected to the circuit pattern 2b of the metal foil via the anisotropic conductive film 8 is shown. Has been done. Circuit pattern 2b of metal foil
Is an antenna circuit, for example.

Hereinafter, the manufacturing process from the circuit substrate to the inlet of the present invention will be described in order, and thereafter,
Assembly of the IC card will be described. First, the metal foil and the support that constitute the circuit substrate will be described in detail. Inlet manufacturing / process [metal foil] The metal foil 2 used is an aluminum foil, a copper foil, a gold foil, which is manufactured by an electrolytic method, a rolling method, a precision rolling method, a foil stamping method (mainly for arts and crafts). Silver foil, zinc foil, nickel foil, tin foil, alloy foil and the like are preferable. Generally, it is preferable to subject these metal foils to an easy-adhesion treatment on the side to be adhered to the base material. The larger the unevenness due to the easy-adhesion treatment, the higher the adhesive strength, but if it is too large, the strength of the metal foil may be weakened. When using a thin metal foil, fine unevenness may occur on the surface of the metal foil, which may cause a problem in reproducibility of fine lines. Further, since the metal foil is usually surface-oxidized by air, it is preferable to perform an antioxidant treatment. Further, aluminum is stabilized by forming a film of aluminum oxide on the surface.

Generally, metal foils used for etching patterns are mostly copper foils and aluminum foils. There are two types of copper foil: rolled copper foil (including precision rolling method) and electrolytic copper foil. The electrolytic copper foil uses a copper sulfate solution as a raw material, electrically deposits copper on a rotating drum in the copper sulfate solution, and winds this to obtain a copper foil. The resulting copper foil becomes a rough surface on the opposite side to the transferred glossy surface of the drum surface. In the subsequent process, the glossy surface has anti-rust treatment and heat resistance treatment, and the rough surface has adhesiveness with other base materials. It is preferable to perform chemical and physical surface roughening treatment (easy adhesion treatment) for improvement. The rolled foil is obtained by rolling a metal strip with a rolling mill having 2 to 4 stages (6 to 20 stages in the case of precision rolling), and usually has high smoothness on both sides. Since the precision rolled foil has good film thickness uniformity, it is used for fine patterns. Since the adhesiveness is weak when it is left as it is after rolling, it is preferable to chemically and physically roughen one surface and to rust-proof and heat-treat the other surface as in the electrolytic copper foil.

The rolled copper foil has good mechanical strength against repeated bending, and is suitable for wiring of moving parts such as a hard disk of a computer and a printer. Electrolytic copper foil is inferior in bending resistance to rolled copper foil, but its cost is low. Since the example of the IC card used in the present invention is not used to bend, even an electrolytic copper foil can be sufficiently used. Aluminum foil is manufactured by rolling.
Aluminum is preferable because it has a higher extensibility than copper and is easy to connect when mechanically caulking. Further, the cost is about 1/5, which is very preferable from the viewpoint of cost reduction. However, since the specific resistance of aluminum is about 1.5 times higher than that of copper, it is necessary to increase the thickness and the thickness of the circuit in order to obtain the same resistance value. Furthermore, aluminum has a higher metal dissolution reactivity during etching than copper,
It is difficult to accurately etch a fine pattern. For this reason, when trying to obtain the same performance as a circuit pattern using copper, it is necessary to take care such as changing the pattern.

The antenna forming method which may be used in the present invention will be briefly described below. [Conductive ink] This is a method in which a metal powder such as silver or copper is mixed with a resin and printed by screen printing or the like to form an antenna. It is about the same cost as etching and is currently used in the market. Since the resistance value in the same cross-sectional area is about 10 times higher than that of the metal foil, it may not be usable depending on the chip used. [Metallic wire] Although it is the cheapest material, it requires a high level of technology to mount a bare chip, and if the resistance value is about the same as that of the etching circuit, the wire diameter will be considerably thicker. Becomes

[Plating] It is possible to increase the thickness of the metal, but since the circuit is formed through the base material such as non-woven fabric or nylon mesh, it is basically the same as the one-sided etching and the small chip. Although there is a drawback in that a planar capacitor cannot be provided by etching or etching, the cost is relatively low and it may become popular in the future. [Metallic powder] This is a method of directly applying metallic powder in a circuit pattern, but the productivity is low and the cost is high. [Vaporization] This is a method of heating metal in high vacuum to vaporize it and depositing it on a film, etc. However, the thickness of the metal film is thin, and the resistance value of the antenna is too high for the IC chip currently used, the communication distance There is a problem that is hard to come out.

[Support] The inlet sheet 1 is selected from an electrically insulating material support. The support can be roughly divided into a rigid substrate and a flexible substrate. A rigid substrate is manufactured by impregnating aramid fiber or glass fiber sheet with a thermosetting resin such as epoxy resin, or paper with a thermosetting resin such as phenol resin, and curing by applying heat and pressure. The thermosetting resin is a thermosetting polymer described below. The rigid substrate has a high elastic modulus against mechanical stress. It is used in widely used electric appliances such as computers, mobile phones, televisions and radios. Since these boards have a certain thickness, it can be used as an inlet sheet for cards,
Caution must be taken. On the other hand, a flexible substrate is a film-shaped support provided with a metal foil circuit and is used for printer heads, wiring in cars, etc. Are often used.

The film-shaped support is unstretched, uniaxially stretched, 2
Although it is produced by a production method such as axial stretching, it is generally known that when stretched, the molecular orientation directions of the resin are aligned, so that a durable film can be obtained. However, there is no problem when oriented under a certain temperature condition and used at room temperature,
When used in an environment where the temperature is higher than a certain temperature, the oriented molecules try to return to their original state, so that the film shrinks and there is a high possibility of causing problems such as curling.

Generally, PET, PETG (a non-crystalline polyester resin which is a trademark of Eastman Chemical Co., obtained by copolymerizing ethylene glycol, cyclohexanedimethanol, terephthalic acid, etc.), PEN, PPS
(Polyphenylene sulfide), PBT (Polybutylene terephthalate), Polyimide film, OPP, PC
(Polycarbonate), ABS (acrylonitrile-butadiene-styrene), PVC (polyvinyl chloride), P
P (polypropylene), PE (polyethylene) or the like is used as a support, and is used by being bonded to a metal foil such as copper or aluminum with an adhesive. It is possible to use these materials also in the present invention.

On the other hand, most of the resins can be directly laminated on the metal foil. However, polyimide etc.
Since it is manufactured by the solvent casting method, it cannot be laminated directly because it has no melting point or heat distortion temperature. Such a resin does not melt but carbonizes when the temperature is raised. Instead, it is directly applied to the metal foil to form a film.

The film-shaped support of the present invention may be transparent, semi-transparent or opaque, and may be colorless, colored or white. These films can be selectively used depending on the intended use. The translucent film and the opaque film are usually a mixture of a resin with an inorganic pigment or an organic pigment. Representative examples of inorganic pigments to be blended are titanium oxide, calcium carbonate, barium sulfate, silica, etc., alone or in a mixture, and various organic pigments are used depending on the type of film resin, Basically, it is preferable to select a resin that is incompatible with the film resin and has a size and a refractive index that diffusely reflect visible light. Some transparent films contain a pigment in an amount that does not impair the transparency. In addition to the above pigments, the film contains various additives such as a plasticizer and an antistatic agent. It is also preferable that the surface of the support is subjected to embossing or the like for deaerating the joining process. As the support having a structure in which the thermoplastic resin layer is directly provided on one of the metal foils, the same constituent materials as the support supplied in the film form can be used.

[Adhesion] The present invention is not limited to the one using a circuit substrate in which a metal foil and a support are adhered using an adhesive or a glue, but can be directly applied by heat and pressure without using an adhesive or a glue. It also includes one using a circuit substrate that is adhered. Examples of the adhesive or glue include polyester, polyurethane, acrylic, phenol, vinyl acetate, vinyl chloride, starch, polyvinyl alcohol, SBR (styrene butadiene rubber), vinyl chloride acetate, etc., which can bond a metal foil and a film. Any material can be used as long as it is used.

For this adhesion, a method of adhering the inlet sheet as a film-like sheet with a metal foil, and a method of adhering the thermoplastic resin serving as a support on the metal foil by melting and extruding Is mentioned.

[Inlet] After a part of the metal foil of the circuit substrate obtained by adhering the support and the metal foil as described above is removed by etching to form a necessary circuit pattern, the structure shown in FIG. As shown in FIG. 6, the bare IC chip 6 can be attached to the base material on which the circuit pattern 2b is formed to obtain an inlet. The inlet serves as a heart component when assembling the non-contact type IC card described below.

The circuit pattern 2b can be formed as follows. A photosensitive resin layer is provided on the metal foil 2 of the circuit substrate, and the circuit pattern is printed on the photosensitive resin layer by using a mask of the circuit pattern formed of a negative or positive photographic film or a chrome film, or printing or lettering. The circuit pattern is directly drawn on the metal foil of the circuit substrate by various methods such as. Using the circuit pattern formed in this way as a mask, the unnecessary metal part except for the circuit pattern part is melted out by so-called etching using a ferric chloride solution or caustic soda solution, etc. The circuit pattern 2b may be formed to manufacture an etching circuit substrate. The circuit substrate can also be made from a circuit substrate having metal foils attached to both sides. With such a circuit substrate, it becomes possible to form a planar capacitor on the circuit substrate. The planar capacitor is a very useful component in the non-contact type IC card when performing tuning for accurately adjusting the frequency. Through-hole plating is used for the circuit substrate with metal foil bonded on both sides.
It is also possible to electrically connect both metal foils by a method of conducting them mechanically or by welding to construct and use a three-dimensional circuit.

[Connection] In the present invention, a bare chip is connected to ACF (anisotropic conductive film), ACP (anisotropic conductive paste),
NCP (non-conductive paste) or other connection resin thermocompression bonding method, using a metal such as solder to heat connection,
Standard connection methods such as ultrasonic bonding, welding, and thermocompression bonding between metals can be used.

The parts such as ICs for manufacturing the inlet will be briefly described below. [IC] The IC chip used is 135 KHz, 4.9
MHz, 6.5MHz, 13.56MHz, 2.54GH
Many z-band bare chips. IC used for IC packaging
Is a bare chip form with bumps on the chip,
There is a form called a package chip in which a chip is die-bonded to a lead frame material that also serves as a terminal part, and a pad portion of the chip and a lead frame are wired with a gold wire or the like and then sealed with an epoxy resin or the like. Recently, CSP (chip size package) with a shape similar to a bare chip
The development of an IC called a is progressing. This CSP, in which a bare chip is resin-sealed and a new electrode is provided, is a technology that was conceived due to the recent increase in the degree of integration of semiconductors.
P can also be used as the bare IC chip of the present invention.

2. IC card material / process The materials / process used from the inlet sheet using the circuit substrate to the final product card are described below. First, a basic block diagram of the IC card is shown in FIG.
Shown in. FIG. 10 is a conceptual sectional view of the IC card of the present invention. Covering layer 3 with adhesive layers 10a and 10b on both sides of an inlet using a circuit substrate (composed of inlet sheet 1, metal foil circuit 2b, IC6, etc.)
a and 3b are joined. The coating layers 3a and 3b are usually provided with a printing layer 14, and a protective layer 13 is provided outside the printing layer 14 as required. There is also a mode in which an intermediate layer described later is used instead of the adhesive layer. Visible information recording layer 12
Can be appropriately provided on the upper surface or the lower surface of the protective layer 13 depending on the display method used. Actually, I
Since the thickness of the C chip 6 is considerably large, the inlet sheet 1
Only the portion around the IC chip portion is recessed downward in the figure, and the IC chip is positioned substantially at the center in the thickness direction. Further, as shown in the figure, the coating layer 3a has an IC
The silicon side surface 6b of the chip may come in.

FIG. 11 also shows a conceptual sectional view of another example of the IC card of the present invention. In this example, there is no adhesive layer 10, and the structural member is the simplest IC card structure including only the inlet and the coating layers 3a and 3b on both sides.
The present invention can be used as an IC card without any problem even with a simple configuration as shown in FIG. 11, and a significant cost reduction is possible. Also in this figure, the inlet sheet 1 usually has a recessed shape as in FIG.

[Coating Layer] The coating layers 3a and 3b are completed I
It is a base material that requires the structural strength of the outermost shell of the C card, and can further be provided with a printing layer 14, a magnetic layer, a protective layer 13, and the like. Film- or sheet-shaped polyester, polycarbonate, ABS, PETG (a non-crystalline polyester resin of the Eastman Chemical Company trademark,
Obtained by copolymerizing ethylene glycol, cyclohexanedimethanol, terephthalic acid, etc.), polyvinyl chloride, polyethylene, polypropylene, nylon, polyimide, polystyrene, polymer alloys, plastic films such as engineering plastics, and metals such as copper and aluminum. Plates, papers, nets, etc. alone or in combination,
A substrate in which glass fiber or paper is impregnated with epoxy resin or the like can be used. Further, depending on the laminated structure of the card, it may also serve as a support. The coating layer may be transparent, translucent or opaque depending on the application. Most translucent and opaque plastic films that are in circulation have white pigments such as titanium oxide, calcium carbonate, and organic pigments kneaded into the resin, or have printing or coating on the surface. .

The coating layers 3a and 3b are adhesive layers 10a and 10b.
Can be used to attach to most materials.

[Adhesive Layer] The adhesive layers 10a and 10b are layers having a function of adhering the inlet sheet 1 and the coating layers 3a and 3b, or the coating layers 3a and 3b and the intermediate layer to one sheet. The bonding method includes a laminating method and an injection method. The laminating method is a method of laminating films and laminating them by hot pressing etc. in the same manner as the circuit substrate preparation. The adhesive resin used for the adhesive layer 10 is generally used such as polyester, ABS, acrylic and polyurethane. An adhesive for dry lamination, a thermosetting resin of a type in which one or more liquids such as epoxy resin are mixed, a hot-melt resin and a thermosetting resin, a moisture-curing resin, and a line-curing resin are preferable. In order to adjust the thickness of the card to a specified value, it becomes necessary to adjust the coating layers 3a and 3b and the inlet sheet 1 as well as the coating amounts of these resins. In particular, the hot melt adhesive is suitable for thick coating because of its high viscosity, and is preferable for increasing the thickness of the card. Although the adhesive can be directly applied to the coating layers 3a and 3b and the inlet, the hot-melt resin adhesive can be manufactured as a rubber-like sheet at room temperature, and is preliminarily formed into a film on a separator paper or the like. Alternatively, the separator paper or the like can be peeled off before use. In some cases, the adhesive layer may be adhered to each film by an adhesive for wet lamination.

The injection method is applied to the coating layers 3a and 3b.
This is a method of molding a card by injecting heat-melted resin between them, and the inlet integrated with the coating layers 3a and 3b can be enclosed at the same time. The resin used is the coating layer 3
It serves as an adhesive for adhering a and 3b and also as a constituent material. The resin used for the adhesive may be the same as the resin used in the laminating method, but the resin may be passed through a narrow space such as between the coating layers 3a and 3b-inlet sheet 1 through several resin supply ports. Since it spreads, it is preferable that the melt viscosity of the resin is lower than that of the hot melt adhesive of the laminating method.

[Intermediate Layer] When a layer similar to the coating layers 3a and 3b is not used as the outermost layer but is used in the intermediate portion, this layer is referred to as an intermediate layer. The intermediate layer can also be made of the same material as the coating layers 3a and 3b, and of course, the same material as the inlet sheet 1 can be used.

[Visible Information Recording Layer] The visible information recording layer 12 is a layer provided when it is necessary to record information such as the balance of the non-contact type IC card and the serial number as character information that can be visually confirmed. In the case of physically creating letters with a laser, when forming a vapor deposition film of tin or the like and recording by thermally destroying the film, a thermosensitive coloring dye such as leuco dye is applied to form a recording layer, One-time recording such as thermal recording on that layer, heat-sensitive type, resin type,
It is also possible to provide a rewritable display layer of magnetic type, electric field type, liquid crystal type or the like.

[Protective Layer] The protective layer 13 is usually a layer provided to protect the printing, visible information recording layer and the like. When the protective layer 13 is provided by various printing and coating, an overlay film is attached. Method is possible. When the protective layer 13 is provided by printing or coating, it is formed from one or more kinds of resins such as polyvinyl acetal, polyvinyl butyral, acrylic resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer, epoxy resin, and the like. It may be formed from a paint or ink in which an inorganic pigment such as aluminum or titanium oxide, an organic pigment such as silicone, polyethylene, or polystyrene fine particles, a lubricant, or the like is dispersed in the resin. The overlay film is a transparent film and can be attached by thermal transfer, thermal lamination, or the like.

[Printing Layer] Usually, the printing layer 14 is provided under the transparent protective layer 13, and is a pattern for giving a decorative effect to the card, a card use clause, or a visible bar code for reading by a machine. It is a layer for printing etc. Printing may be performed in advance on the coating layers 3a and 3b with good heat resistance after the card is in a card state. When printing in advance, the base material may expand or contract due to heat during card molding, so print with a pattern that has been contracted or expanded in advance, or print on a base material that has been dimensionally stabilized by heat treatment in advance. Is preferred.

[Molding] The non-contact type IC card is molded by a laminating method or an injection molding method. In the laminating method, a cover layer sheet, an inlet on which an IC is mounted, a sheet paste, etc., can be overlaid and heated by a hot press or the like to be pressure bonded. At this time, heat is applied to soften and cure the adhesive,
If the molding conditions are not selected, the card may curl or the IC chip may be destroyed. It is preferable to make holes in the IC chip portions such as the intermediate layer, the adhesive layer, and the inlet sheet so as to make the thickness of the card uniform. It is preferable that the laminator be vacuum degassed before molding.

On the other hand, in the injection method, the molten resin can be injected between the two front and back coating layers 3a and 3b set in the mold to be molded. The inlet is previously temporarily fixed to the coating layer 3a or 3b on one side.
Since the injected resin is extruded at a high pressure through a small hole, the injection port is generally located at the center of the sheet, and the resin may be radially oriented from the injection port. Coating layer 3
Curling may occur unless the thicknesses of a and 3b, resin type, extrusion rate, melt viscosity, heating / cooling conditions, etc. are optimized.

In the present invention, when the coating layers 3a and 3b and the circuit substrate are both adhered using a heat-fusible resin, these thermoplastic resins are once melted and fused and integrated with each other. There are combinations that make it possible. If the film-like thermoplastic resin is heated to its melting point or higher in a state where there is no restriction on the external shape such as mold or pressure, the film may be deformed so much that the original shape cannot be retained. It is more preferable to pressurize and heat the medium because the shape is maintained.

An adhesive is often used for the above-mentioned bonding. In particular, epoxy resin, phenol resin and the like are preferably used as the thermosetting adhesive. There is also a one-pack type and a mixture of two or more kinds of a main agent and a curing agent. Since such an adhesive shortens the pot life after mixing, attention must be paid to the manufacturing process control. However, compared with the one-pack type, the curing time and the degree of freedom in selecting the resin characteristics after curing are large, so that it is preferably used.

[Punching] To make a card from a molded sheet, one card can be cut with a Thomson blade attached to an electric, pneumatic, or hydraulic press and a male / female blade.

[Another Configuration Example of IC Card] In the above example, an example of assembling an IC card using the adhesive layer 10 has been described. However, if the heat-fusible thermoplastic resin is used for the coating layers 3a and 3b and the intermediate layer 11 that is used as necessary, as in the inlet sheet 1, a layer made of the heat-fusible thermoplastic resin is used. Since the bonding between the 3a, 3b, 11 and the inlet sheet 1 can be performed by bonding by heat, it is preferable in terms of cost reduction. Further, in particular, the use of the same resin is more preferable because the adhesiveness is further enhanced. In this case, since the heat shrinkage rate, elastic modulus, color tone, etc. of each layer can be made the same, the cross section of the card does not have a fault and the appearance of the card is not only good. Malfunction is unlikely to occur. Further, the elastic modulus of each layer is the same, and the degree of crushing of the card cut surface is smaller than that of the card manufactured using the adhesive layer, which is preferable when the card is mechanically conveyed. Further, the inlet sheet 1, the coating layers 3a and 3b, and the intermediate layer 11 used as necessary are all made of a heat-fusible thermoplastic resin, and all bonding is performed by heat bonding, which is extremely effective. A large and large cost reduction is possible.

[0055]

The present invention will be described in more detail with reference to the following examples, but of course the present invention is not limited thereto. (Embodiment 1) This embodiment 1 will be described with reference to FIGS. 1, 2, 3, 4, and 7 described above. As shown in FIGS. 1 to 4, an inlet sheet 1 (PET, lumirror: 50 μm thick) which becomes an inlet sheet by an etching method.
A circuit pattern 2b including a 4-turn loop antenna was provided on a copper foil having a thickness of 18 μm on Toray Co., Ltd., and a through hole portion 4 having a diameter of 1 mm was further provided to prepare a circuit board. A film-shaped curable resin layer 8 (flip tack FC-110A: film thickness 3 on the electrical connection terminals of the circuit board).
Bare IC chip 6 (SLE55R04, 1.5 mm × 0 μm, thermosetting resin containing gold-plated resin particles, manufactured by Hitachi Chemical Co., Ltd.) was temporarily attached, and gold bumps 7 were provided thereon by a wire bonder method using a face-down method. 1.8
mm, thickness 300 μm, manufactured by Infineon Co., Ltd.) were sequentially placed, and then the curable resin layer 8 was cured at a pressure of 0.1 kgf and a temperature of 180 ° to produce an inlet.

Next, as shown in FIG. 11, a hot-melt adhesive layer 10 (polyester, Aron melt: manufactured by Toagosei Co., Ltd.) having a thickness of 100 μm was formed on the front and back of the inlet obtained by the above operation, and the coating layers 3a and 3b. As an insulating base material (PET-G, Diafix: manufactured by Mitsubishi Plastics Co., Ltd.), and punched into a card mold after laminating to obtain a non-contact type IC card. The thickness from the silicon surface to the surface of the mounting body was 180 μm.

(Example 2) A conductive silver ink (Dotite FA353: manufactured by Fujikura Kasei Co., Ltd.) was screen-printed (stainless steel mesh 200 wire) into a coil shape and dried to a thickness of 20 μm.
It was printed on a polyethylene terephthalate film (PET, Lumirror: manufactured by Toray Industries, Inc.) having a thickness of 50 μm to be an inlet sheet so as to have a length of m, and the solvent was dried at 100 ° C. for 30 minutes to prepare a circuit pattern 2b including a loop antenna. . Then, resist printing and jumper printing were continuously performed. Finally, a printed antenna dried and cured at 130 ° C. for 30 minutes was used, and a chip having a thickness of 450 μm (SLE55R04, thickness 4) was used instead of the chip used in Example 1.
An IC card was obtained in the same manner as in Example 1 except that 50 μm, manufactured by Infineon Co., Ltd. was used. The thickness from the silicon surface to the surface of the mounting body was 100 μm. (Example 3) 38 μm polyethylene naphthalate film (PEN: Theonex: used as an inlet sheet)
Conductive carbon ink (DY-15) by gravure printing on a base material with aluminum foil of 20 μm on both sides of Teijin Ltd.
0H-30: manufactured by Toyobo Co., Ltd.) is used as a coil antenna in resist printing, and a circuit pattern 2b including a loop antenna obtained by etching with a sodium hydroxide solution is used,
An IC card was obtained in the same manner as in Example 1 except that the resist print was not removed. The thickness from the silicon surface to the surface of the mounting body was 180 μm.

(Comparative Example 1) IC chip 5 (SLE55R
04, thickness 150 μm, manufactured by Infineon)
The thermosetting resin layer (A
-1002: Nagase Ciba Co., Ltd.) is applied in a predetermined amount, and then applied.
First reinforcing member (SUS-301, thickness 100 μm, large
5 mmφ) was placed. 0.02 using a pressure jig
kgf / mm ^TwoPressurize with the load of, and then heat cure
And fix the reinforcing member to the silicon side of the bare IC chip.
Then, an inlet having a reinforcing member was obtained. That inlet
An IC card was obtained from the above in the same manner as in Example 1. Silico
The thickness from the inner surface to the surface of the mounting body was 210 μm.

Comparative Example 2 An IC card was obtained in the same manner as in Example 1 except that the thickness of the reinforcing member used in Comparative Example 1 was changed to 200 μm. The thickness from the silicon surface to the surface of the mounting body was 160 μm. (Comparative Example 3) The thickness of the chip used in Comparative Example 1 was set to 200.
An IC card was obtained in the same manner as in Example 1 except that the bare chip changed to μm was used and the reinforcing member was not used.
The thickness from the silicon surface to the surface of the mounting body was 220 μm.

(Evaluation) The samples prepared in Examples and Comparative Examples were measured by the following method. Communication test is shown in Figure 12.
It was confirmed during each of the following tests whether the communication with the IC card 103 is normally performed by the reader / writer 142 connected to the personal computer 141 as shown in FIG. 1. Push-in test A card molded on silicone rubber with a hardness of 5 mm and a hardness of 50 is placed, and a SUS with a tip diameter of 10 mm is placed on the chip part.
A 304 metal ball is pressed and pushed in at a speed of 1 mm / min, and a communication test is appropriately performed when each force value is reached, and the force at which the communication test becomes impossible is determined. General application conditions (test environment etc.) in the test are based on JIS X6305. ◯: 35 N or more, Δ: 25 N or more and less than 35 N, ×: 2
Less than 5N 2. Metal ball drop test A molded card is placed on a steel plate with a thickness of 10 mm, a metal ball made of SUS304 having a mass of 10 g is dropped from a certain height on the chip portion, and a communication test is performed at each height as appropriate. And determine the height when the communication test becomes impossible. General application conditions (test environment etc.) in the test are JIS X 6305
Comply with. ○: 10 cm or more, Δ: 5 to less than 10 cm, ×: 5 cm
Less than

3. Bending test Tested by the method specified in ISO / IEC 10536-1. ○ if communication test is good, × if not. 4. Torsion test Tested by the method specified in ISO / IEC 10536-1. ○ if communication test is good, × if not. 5. Chip bending strength Fix one end of the card to the table with a clamp so that the chip part of the card comes to the corner of the desk, bend by 90 degrees by hand perpendicular to the longitudinal direction of the card and keep it for 30 seconds, then the card If the communication test after returning to the original flat state is good, ○, if not, x. General application conditions (test environment, etc.) in the test conform to JIS X 6305. The evaluation results of the above tests are summarized in Table 1 below.

[0062]

[Table 1]

[0063]

According to the present invention, by setting the thickness of the bare IC chip to 300 μm or more, it is possible to provide practical strength without a reinforcing member, and to perform another step for reinforcing. It has become possible to achieve a significant cost reduction without the need. Further, unlike the case where the chip is mounted and reinforced with a metal plate or the like, strength can be given in the step of processing the chip, so that the chip strength is extremely small and good.

[Brief description of drawings]

FIG. 1 is a plan view showing a circuit substrate used in the present invention.

FIG. 2 is a cross-sectional view taken along the line A-A ′ of the circuit substrate of FIG.

FIG. 3 is a plan view showing a circuit substrate after etching.

4 is a cross-sectional view taken along the line A-A ′ of the circuit board of FIG.

FIG. 5 is a plan view showing an inlet used in the present invention.

6 is a cross-sectional view taken along the line B-B ′ of the inlet of FIG.

7 is an enlarged cross-sectional view showing a joined state of the IC mounting portion of the circular portion shown in FIG.

FIG. 8 is a cross-sectional view showing a state in which a point pressure strength test is performed with the bare IC chip exposed.

FIG. 9 is a cross-sectional view showing a state in which a bare IC chip is finished into an IC card without using a reinforcing member and then a point pressure strength test is performed.

FIG. 10 is a conceptual sectional view showing an embodiment of an IC card of the present invention.

FIG. 11 is a conceptual cross-sectional view showing another embodiment of the IC card of the present invention.

FIG. 12 is a schematic diagram showing a state of communication distance measurement of an IC card.

[Explanation of symbols]

1 support 2b Circuit pattern with metal foil 3a, 3b coating layer 6 Bare IC chip 7 bumps

Claims (4)

[Claims] 1. A bare I having a thickness of at least 300 μm or more.
An IC chip mounting body having an inlet sheet having a C chip mounted thereon and a coating layer, and having no reinforcing member for protecting bare IC chips and having a total thickness of 700 to 900 μm. 2. The IC chip package according to claim 1, wherein the thickness from the side surface of the bare IC chip to the surface of the package is 200 μm or less. 3. The tensile strength of the inlet sheet is 100.
The IC chip mounting body according to claim 1, which has a pressure of at least MPa. 4. The IC chip package according to claim 1, wherein a thickness of at least a connection portion of a bare IC chip of a circuit provided on the inlet sheet is 50 μm or less.