JP4349597B2 - IC chip manufacturing method and memory medium manufacturing method incorporating the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a non-contact IC card that transmits and receives data to and from an external device, an IC chip for a memory medium such as a non-contact IC tag, and a memory medium equipped with the IC chip.
[0002]
[Prior art]
Conventionally, IC cards have been used in various information fields. However, in order to improve convenience and durability from contact type IC cards that are mechanically connected to external devices such as readers, recently, external devices have been used. There is known a non-contact type IC card that allows data to be transmitted and received simply by approaching without touching.
[0003]
[Problems to be solved by the invention]
The first idea of the non-contact IC card as described above was a type in which the antenna was formed in the card base, so that the manufacturing process was complicated and the yield of non-defective products was not increased. Therefore, as another form, a method has been considered in which an antenna is directly formed on a substrate on which an IC chip is mounted, and an IC module having the antenna is inserted into a card or tag. However, a memory medium such as a non-contact IC card or a non-contact IC tag of this type has a drawback of high cost due to a large number of parts and a long manufacturing process, which has been a major obstacle to full-scale spread.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is a method for manufacturing an IC chip for a memory medium such as a non-contact IC card and a non-contact IC tag, in which an antenna for transmitting and receiving data is provided on the chip itself. And, it is characterized by comprising the following steps.
(1) A first step of forming a passivation film as an insulating layer on a portion of a wafer-state IC chip excluding a connection portion with an antenna.
(2) A second step of forming a seed layer on the wafer so as to cover the passivation film in order to ensure conduction with the connection portion of the chip circuit and improve the adhesion of the insulating layer.
(3) A third step of patterning a photoresist layer on the seed layer.
(4) A fourth step of forming a patterned antenna by electroplating and stripping the photoresist after plating.
(5) A fifth step in which the seed layer is removed by ion etching to form a pattern antenna on each IC chip on the wafer.
(6) A sixth step of cutting an IC chip on which an antenna is formed from a wafer after molding with a sealing resin.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
IC chip produced in the present invention, the non-contact IC card, an IC chip for memory medium such as a non-contact IC tag, Ru der those in a form an antenna for transmitting and receiving data to the chip itself.
[0006]
That is, in a general-purpose IC chip having a circuit formed, by forming the antenna in redistribution of electric plating key, since to obtain a dedicated chip with an antenna, and the conventional antenna sheets, the mounting substrate with a dedicated antenna The memory medium such as a non-contact IC card or a non-contact IC tag can be manufactured by simply embedding in a card or tag.
[0007]
When the antenna is formed on the chip itself, an insulating layer may be formed on a portion of the chip where the circuit is formed, and the antenna may be formed on the insulating layer by wiring by plating, or the circuit in the chip may be formed. You may make it form an antenna with the wiring by plating in the part except a surface. In addition, the antenna can be configured with a plurality of antenna layers each having an insulating layer interposed therebetween depending on the communication distance and the characteristics of the external device.
[0008]
In addition, since the antenna is directly formed on the chip itself, a future semiconductor in which a connection method with a mounting substrate such as a spherical semiconductor has not been established can be easily processed into an IC card or a tag.
[0009]
In the present invention, an antenna is formed by forming a wiring again on an IC chip for a non-contact IC card in a wafer state having an interface circuit with the antenna or an IC chip for a non-contact IC tag via an insulating layer. . The manufacturing process will be described below with reference to the drawings.
[0010]
In the first step, as shown in FIG. 1A, polyimide, SiN, or the like is coated on the portion of the IC chip 10 in the wafer state excluding the connection portion with the antenna, that is, on the Al circuit wiring pattern 11. Thereby, the passivation film 12 is formed. Instead of this process, a wafer on which the passivation film 12 has been formed in advance may be purchased by a semiconductor manufacturer.
[0011]
In the second step, as shown in FIG. 1B, the wafer is covered so as to cover the passivation film 12 in order to ensure conduction with the connection portion of the chip circuit and to improve the adhesion of the insulating layer formed in the next step. A seed layer 13 is formed thereon. Specifically, a metal thin film of Ti, Ta, TiN, TaN, Cu or the like is formed with a thickness of about 0.2 μm using a sputtering apparatus.
[0012]
In the third step, a photoresist 14 is patterned on the seed layer 13 as shown in FIG. As a procedure, first, a photoresist is applied on the entire surface by a spin coater. The photoresist to be used is selected to have an optimum viscosity according to the required film thickness. Next, using a photomask on which an antenna pattern having a necessary function is formed, the photoresist is baked by alignment exposure. The photoresist is preferably a positive type in consideration of resolution and stability. After the exposure, the uncured portion of the photoresist is removed by development.
[0013]
In the fourth step, as shown in FIG. 1D, a patterned antenna 15 is formed by electrolytic copper plating, and the photoresist 14 is peeled off by alkali such as sodium hydroxide after plating. The plating thickness is 10 μm or more. The resist peeling may be performed by a dry process such as oxygen plasma.
[0014]
In the fifth step, as shown in FIG. 1E, the seed layer 13 is removed by reactive ion etching using a halogen-based gas. At this time, the pattern of the antenna 15 is also etched at the same time, but there is no problem in function because the thickness is 10 μm or more.
[0015]
In addition, depending on the communication distance and the characteristics of the external device, communication may not be possible with only the antenna formed above. In such a case, by repeating the above steps, two or more antenna layers may be used. An antenna may be configured. Specifically, in order to connect and connect each antenna layer, an insulating layer is formed on the lower antenna layer by a spin coater or the like, and then the insulating layer is processed by laser processing using a carbon dioxide laser, for example. Is removed to expose the lower antenna layer, and the above-described process is performed again to form the upper antenna layer. Such a connection portion between the antenna layers may be formed by a mechanical processing method such as cutting in addition to laser processing, or a portion to be a connection portion is masked with a resist or the like, and an insulating layer is applied and formed. Then, it may be formed by peeling the resist.
[0016]
Through the above steps, the pattern-like antennas 15 are formed on the individual IC chips 10 on the wafer. In the present invention, as shown in FIG. Perform the mold. Specifically, an epoxy resin is applied to the surface of the wafer by a silk screen printing method using a metal stencil. Thereby, when an IC chip is mounted on a card, a tag, or the like, durability against external stress and chip circuit corrosion is improved. Here, if restrictions on the thickness of the memory medium containing the IC chip allow, the front and back of the wafer are sealed with a resin by transfer molding to prevent warping and residual stress during resin curing shrinkage. Increased reliability can be expected.
[0017]
Finally, IC chips each having an antenna are cut out from the wafer and mounted on a memory medium such as a card or tag.
[0018]
FIG. 2 is an exploded perspective view showing an example in which a non-contact IC card is configured by mounting the IC chip of the present invention on a card. For applications that require reliability against external stress when being carried, such as the non-contact IC card 20, it is effective to mount the IC chip 30 together with the reinforcing sheet 31 in the card 20 as shown. As the reinforcing sheet 31, a metal plate such as stainless steel or titanium or a plastic plate with high mechanical strength such as polycarbonate is processed to a size equal to or larger than the chip size. The central PVC sheet 41 is provided with a chip-sized hole 41a. The IC chip 30 with the reinforcing sheet 31 is inserted into the hole 41a from below, and sandwiched between the PVC sheets 42 and 43 from the upper and lower sides, respectively. The card C on which the IC chip is mounted is configured.
[0019]
【The invention's effect】
As described above, according to the present invention, since provided an antenna for transmitting and receiving a data to the chip itself, only the antenna is formed in a general-purpose IC chip on which a circuit is formed by rewiring the electric plating key, A dedicated chip with an antenna can be easily obtained, and by embedding the dedicated chip with an antenna in a card or tag, a memory medium such as a non-contact IC card or a non-contact IC tag can be manufactured. Costs can be reduced by reducing the number of points.
[Brief description of the drawings]
FIG. 1 is a process diagram showing a procedure of a manufacturing method of an IC chip according to the present invention.
FIG. 2 is an exploded perspective view showing an example in which a non-contact IC card is configured by mounting an IC chip manufactured according to the present invention on a card.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 IC chip 11 Circuit wiring pattern 12 Passivation film 13 Seed layer 14 Photoresist 15 Antenna 16 Sealing resin 20 Non-contact IC card 30 IC chip 31 Reinforcement sheet 41, 42, 43 Vinyl chloride sheet

Claims (3)

Contactless IC card, in a memory medium such as a non-contact IC tag, an antenna for transmitting and receiving data to a method for manufacturing an IC chip formed by providing the chip itself, IC, characterized in that comprises the following steps Chip manufacturing method.
(1) A first step of forming a passivation film as an insulating layer on a portion of a wafer-state IC chip excluding a connection portion with an antenna.
(2) A second step of forming a seed layer on the wafer so as to cover the passivation film in order to ensure conduction with the connection portion of the chip circuit and improve the adhesion of the insulating layer.
(3) A third step of patterning a photoresist layer on the seed layer.
(4) A fourth step of forming a patterned antenna by electroplating and stripping the photoresist after plating.
(5) A fifth step in which the seed layer is removed by ion etching to form a pattern antenna on each IC chip on the wafer.
(6) A sixth step of cutting an IC chip on which an antenna is formed from a wafer after molding with a sealing resin. The method of manufacturing an IC chip according to claim 1, wherein after the fifth step, an insulating layer is formed on the antenna, and then the insulating layer is partially removed to expose the antenna. A method of manufacturing an IC chip, wherein the antenna is configured with two or more antenna layers by repeatedly performing the second to fifth steps. After the step of claim 1 or 2, the manufacturing method of the characteristics and to Rume Molly medium to implement the IC chip cut out from the wafer to the card or tag.

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