JP2001053395A - Electronic circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly prevent breaking of wires, etc., of a connecting circuit for connection from a circuit pattern to a semiconductor IC chip due to repeated uses. SOLUTION: An electronic circuit board is composed by arranging, on a base material 1, a semiconductor IC chip 20, a circuit pattern 21, and a connecting circuit 22 for connection form end points 21a, 21b of a circuit pattern 21 to the connecting terminals of the semiconductor IC chip 20, and mounting the semiconductor IC chip 20 with the face downward on the base material 1 via an underfilling material 24. In this case, the board has branch circuits 22b, 22c which are branched circuits of the connecting circuit 22 branched outside the peripheral brim part of an underfilling material 26, and wiring is performed so that the branched circuits 22b, 22c can be connected to the connecting terminals from different directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit board provided with a semiconductor IC chip, a circuit pattern, and a connection circuit from an end point of the circuit pattern to a connection terminal of the semiconductor IC chip. In particular, it relates to a flexible and thin electronic circuit board suitable for use in a non-contact type IC card.

[0002]

2. Description of the Related Art A non-contact type IC card is a semiconductor IC having a function for a memory, a microcomputer and wireless communication.
This is a resin card having a built-in chip and a coiled antenna for wireless communication. Such an IC card has a much larger memory capacity than a magnetic card, and can transmit and receive card information wirelessly through an antenna coil without passing through electrical contacts. It has been widely used as a recording medium that is more convenient to handle than IC cards.

As shown in FIGS. 8 and 9, a conventional non-contact type IC card 1 has an antenna coil 11 and an antenna coil 11 on a surface of a thin circuit substrate 10 made of an organic polymer material such as polyethylene terephthalate. Antenna coil 11
From the start point 11a and end point 11b of the semiconductor IC chip 12
A connection circuit 13 is formed to communicate with the connection terminal 12a of the semiconductor IC chip 12 via the underfill material 14. An electronic circuit board is formed by fixing the IC chip 12, an intermediate layer 15 is formed with a hot melt material so as to cover them, and a surface film 16 is further attached to the intermediate layer 15. In addition, if necessary, a reinforcing member 17 such as a thin metal plate is provided on the semiconductor IC chip 12 to prevent the occurrence of chip cracks due to a mechanical external force applied to the semiconductor IC chip 12. Note that reference numeral 1 in FIG.
2b is a dummy terminal for inspection and positioning of the semiconductor IC chip 12, 13b is an antenna coil 11 and a connection circuit 1
3 is an insulating film for electrical insulation with the insulating film 3.

The antenna coil and the connection circuit 13 are made of Ag
It is formed by various methods such as screen printing using a conductive paste such as a powder paste, etching of a metal foil such as Cu, or a thin film forming technique.

For example, as shown in FIGS. 10 and 11, the circuit terminal 13a of the connection circuit 13 and the connection terminal 12a of the semiconductor IC chip 12 are connected by wire bonding 18a.
The semiconductor IC chip 12 is fixed to the circuit substrate 10 with an adhesive (not shown) to form an electronic circuit board, and the intermediate layer 15 is formed with a hot melt adhesive so as to cover the electronic circuit board. A structure in which a surface film 16 is further attached to the intermediate layer 15 is also known. Reference numeral 18a is a protection member for the bonding wire 18.

[0006]

However, in the case of the above-mentioned conventional IC card, especially an IC card having a flexible electronic circuit board having a thickness of 0.5 mm or less, a semiconductor If a force that pushes the mounting part of the IC chip 12 is repeatedly applied or the card is repeatedly bent,
A connection circuit 13, a bonding wire 18, or the wire 18 from the start point 11a and the end point 11b of the antenna coil 11 to the connection terminal 12a of the semiconductor IC chip 12.
It has been found that the connection between the connection circuit 13 and the circuit terminal 13a is broken, and the function of the card is impaired.

In particular, the disconnection of the connection circuit 13 will be described in detail. If the reinforcing member 17 is not provided, the mounting portion of the semiconductor IC chip 12 sinks due to the pressure applied to the mounting portion of the semiconductor IC chip 12 in the card. When the partial bend of the card due to the above or the local bend of the mounting portion of the semiconductor IC chip 12 when the entire card is bent, the bend of the card is locally generated near the peripheral portion of the underfill material 14. To be refracted,
It has been clarified that stress concentrates at or near the periphery of the underfill material 14 in the connection circuit 13 and this is repeated, whereby the connection circuit 13 is disconnected.

In a structure in which the reinforcing plate 17 is provided on the semiconductor IC chip to secure the mechanical strength of the semiconductor IC chip, the area of the reinforcing plate 17 is usually 1.5 times the area of the chip. When the rigidity is high and there is almost no partial bending of the reinforcing plate 17, the sinking of the mounting portion of the semiconductor IC chip 12 caused by the pressure on the mounting portion of the semiconductor IC chip 12 in the card occurs. When the card is partially bent due to the above, or the local bending of the mounting portion of the semiconductor IC chip 12 when the card is bent as a whole, the bending of the card near the periphery of the reinforcing plate 17 The stress is concentrated on the periphery of the reinforcing plate 17 in the connection circuit 13 or in the vicinity thereof, and this is repeated, whereby the connection circuit 1 There was found to be broken.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electronic circuit board capable of reliably suppressing the occurrence of disconnection or the like of a connection circuit leading from an antenna coil to a semiconductor IC chip due to repeated use or the like.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a semiconductor IC chip, a circuit pattern, and a connection circuit extending from an end point of the circuit pattern to a connection terminal of the semiconductor IC chip. An electronic circuit board having the semiconductor IC chip mounted on the substrate via an underfill material in a face-down state, wherein the connection circuit is provided outside a peripheral edge of the underfill material. A first feature is that the circuit has a branched circuit, and the branch circuit is wired so as to communicate with the connection terminal from different directions.

The present invention also provides a semiconductor IC chip, a circuit pattern, and the semiconductor IC chip from an end point of the circuit pattern.
A connection circuit communicating with connection terminals of the C chip on a base material, wherein the semiconductor IC chip is mounted on the base material via an underfill material in a face-down state; A second feature is that a circuit terminal for connecting a connection circuit and the connection terminal extends over at least two edges of the semiconductor IC chip and is exposed outside a peripheral portion of the underfill material. I have.

The present invention also provides a semiconductor IC chip, a circuit pattern, and the semiconductor IC chip from an end point of the circuit pattern.
A connection circuit communicating with connection terminals of the C chip on a base material, wherein the semiconductor IC chip is mounted on the base material via bonding wires in a face-up state; A connection circuit is branched outside a peripheral portion of the semiconductor IC chip, and a circuit terminal for connecting the connection circuit and the bonding wire is provided outside the peripheral portion of the semiconductor IC chip. A third feature is that the bonding wire for connecting to the connection terminal is provided across the edge of the semiconductor IC chip.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings. Note that the present invention is not limited to the present embodiment, and the dimensions and the like can be appropriately changed.

First, a first embodiment of an electronic circuit board according to the present invention will be described with reference to FIGS. In these figures, reference numeral 2 indicates an electronic circuit board.

As shown in FIG. 1, the electronic circuit board 2 comprises
A semiconductor IC chip 20, an antenna coil (circuit pattern) 21, and a start point (end point) 2 of the antenna coil 21
1a and the end point (end point) 21b to the semiconductor IC chip 20
And a connection circuit 22 that communicates with the connection terminal 20a.

The size of the semiconductor IC chip 20 is 3 m.
It is mx 2 mm square and is mounted on the lower exterior plate 23 via the underfill material 24 in a face-down state. On the surface of the semiconductor IC chip 20, in addition to the connection terminals 20a, for example, to check the function of the semiconductor IC chip 20, or mount the semiconductor IC chip 20 in parallel with the lower exterior plate 23 when mounting the semiconductor IC chip 20. Dummy terminals 20b are formed.

In this embodiment, a 0.1 mm thick, 6 mm × 5 mm square metal (stainless steel) reinforcing plate 25 for preventing the chip from cracking is provided on the semiconductor IC chip 20 with an adhesive ( (Not shown).

As shown in FIG. 2, the antenna coil 21
The connection circuit 22 is formed by a screen printing method using an Ag paste. In the present embodiment, the antenna coil 21 is formed with six turns at a width of 0.2 mm and an interval of 0.2. Also, connection circuit 2
2, a circuit terminal 22a is formed at the distal end. In the present embodiment, the circuit terminal 22a is 0.3 mm.
× 0.3 mm square. It should be noted that the terminal 21 b of the antenna coil 21 in the connection circuit 22 is connected to the circuit terminal 22.
An electrical insulating film 26 is provided in a portion reaching “a” by a known method so as to straddle the antenna coil 21.

The connection circuit 22 has branch circuits 22 b and 22 c branched outside the periphery of the reinforcing plate 25, and these branch circuits 22 b and 22 c are bidirectional through at least two edges of the semiconductor IC chip 20. Are connected to the connection terminals 20a of the semiconductor IC chip 20.

The underfill material 24 is an adhesive containing Au particles and having anisotropic conductivity.
The semiconductor IC chip 20 is fixed on the lower exterior plate 23 while ensuring continuity between the connection terminal 20a of the connection circuit 20 and the circuit terminal 22a of the connection circuit 22. The underfill material 24 is disposed such that the peripheral edge thereof is outside the peripheral edge of the semiconductor IC chip 20.

In the electronic circuit board 2 configured as described above, the connection circuit 22 branches off outside the periphery of the reinforcing plate 25, and the connection terminals 20 a of the semiconductor IC chip 20 pass through the two edges of the reinforcing plate 25. Therefore, if the stress is concentrated on the peripheral portion of the reinforcing plate 25 or in the vicinity thereof and local repetition of refraction is performed, even if one of the branch circuits is broken, conduction is secured by the other branch circuit. Therefore, there is almost no risk of causing trouble by repeated use.

When an IC card is manufactured using the electronic circuit board 2, the electronic circuit board 2 may be provided with this type of urethane hot melt or the like, as in the prior art (see FIG. 8). An ordinary thermoplastic organic polymer material used in the technology is used as the intermediate layer, and as the upper exterior plate, a thin plate of a predetermined size and shape made of an organic polymer material such as polyethylene terephthalate is formed and hot pressed. Make it.

When the reinforcing plate 25 is not provided,
For example, as in the electronic circuit board according to the second embodiment shown in FIG. 3, the connection circuit 22 is branched outside the periphery of the underfill material 24. As a result, stress concentrates on the peripheral edge of the underfill material 24 or in the vicinity thereof, and due to local repetition of refraction, even if one of the branch circuits is broken, conduction between the under branch material 24 and the antenna coil 21 is caused. Therefore, as in the case of the electronic circuit board 2 of the first embodiment, for example, even when the present invention is applied to a non-contact type IC card having a surrounding property, there is almost no possibility that trouble will be caused by repeated use.

Next, a third embodiment of the electronic circuit board according to the present invention will be described with reference to FIGS. In these drawings, the same reference numerals are given to the same parts as those in the first embodiment, and description thereof will be omitted.

In this embodiment, instead of the branch circuits 22b and 22c in the first embodiment, the circuit terminal 22a of the connection circuit 22 is replaced by the connection terminal 2 of the semiconductor IC chip 20.
0a, and covers two edges of the semiconductor IC chip 20, and a part thereof is exposed outside the peripheral portion of the reinforcing member 25.

In the flexible electronic circuit board 2 manufactured as described above, when a force which pushes the mounting portion of the semiconductor IC chip 20 or the repeated card is bent, the underfill material is formed. A circuit that leads to the connection terminal 20a of the semiconductor IC chip 20 even if the thin wiring in the peripheral portion or the vicinity thereof is not greatly deformed, disconnection due to the deformation is avoided, and further directional stronger deformation is received. Since the terminal 22c is formed with a large area,
Disconnection of the connection circuit between the semiconductor IC chip 20 and the antenna coil 21 can be minimized. Therefore, as in the first embodiment, for example, even when the present invention is applied to a non-contact type IC card having a surrounding property, there is almost no possibility that a trouble is caused by repeated use.

When the reinforcing plate 25 is not provided,
For example, as in the case of the electronic circuit board of the fourth embodiment shown in FIG.
It includes the connection terminals 20a of the C chip 20 and covers two edges of the semiconductor IC chip 20, and a part thereof is exposed outside the peripheral portion of the underfill material 24. As a result, stress concentrates on the periphery of the underfill material 24 or in the vicinity thereof, and conduction with the antenna coil 21 is ensured even when local repetition of refraction occurs. Similar to the circuit board 2, for example, even when applied to a non-contact type IC card having a surrounding property, there is almost no possibility that trouble will be caused by repeated use.

Next, an electronic circuit board according to a fifth embodiment of the present invention will be described with reference to FIG. In these drawings, the same reference numerals are given to the same parts as those in the first embodiment, and description thereof will be omitted.

In this embodiment, the semiconductor IC chip 20
And the circuit terminal 22a of the connection circuit 22 are connected by a bonding wire 27. The connection circuit 22 is branched outside the periphery of the semiconductor IC chip 20, and the circuit terminals 22 a provided at the distal ends of the branch circuits 22 b and 22 c are arranged such that the bonding wire 27 straddles two sides of the semiconductor IC chip 20. Are located.

In the electronic circuit board 2 of the fifth embodiment, the connection terminals 20 a of the semiconductor IC chip 20 and the connection circuit 22 Since the circuit terminals 22a are connected by two bonding wires 27 in different directions, even if one of the bonding wires is broken, conduction to the antenna coil 21 is ensured by the other bonding wire. Similar to the electronic circuit board 2 of the first embodiment, for example, even when applied to a non-contact type IC card having a surrounding property, there is almost no possibility that trouble will be caused by repeated use.

In each of the above embodiments, the lower exterior plate 2
The antenna coil 21 and the connection circuit 22 on the surface of
g was formed by screen printing technology using paste, but the patterning of the antenna conductor film by etching a metal foil such as Cu or Al, the patterning by selective plating of a metal such as Cu or Ni, or the Al or the like by a thin film forming process. In any of the metal thin film patterning, an electronic circuit board having the same configuration as that of the present invention can be manufactured.

In the first, second and fifth embodiments, the connection circuit is branched and two branch circuits are provided. However, it goes without saying that the connection circuit may be branched into two or more.

The electronic circuit board according to the present invention is particularly suitable as an electronic circuit board for a non-contact type IC card provided with an antenna coil as a circuit pattern.
It goes without saying that the present invention can be applied to other electronic circuit boards.

[0034]

According to the electronic circuit board of the present invention, it is possible to reliably prevent the disconnection of the connection circuit from the circuit pattern to the semiconductor IC chip due to repeated use or the like. Therefore, for example, even when applied to a non-contact type IC card, a highly reliable card can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a first embodiment of the present invention.

FIG. 2 is a schematic plan view showing a wiring pattern in the same embodiment.

FIG. 3 is a schematic plan view showing a second embodiment of the present invention.

FIG. 4 is a schematic plan view showing a third embodiment of the present invention.

FIG. 5 is a schematic plan view showing a wiring pattern in the same embodiment.

FIG. 6 is a schematic plan view showing a fourth embodiment of the present invention.

FIG. 7 is a schematic plan view showing a fifth embodiment of the present invention.

FIG. 8 is a schematic sectional view showing a configuration of a conventional non-contact type IC card.

FIG. 9 is a schematic plan view showing a wiring pattern of an electronic circuit board and an arrangement of semiconductor IC chips in the non-contact type IC card.

FIG. 10 is a schematic sectional view showing a configuration of a conventional non-contact type IC card.

FIG. 11 is a schematic plan view showing a wiring pattern of an electronic circuit board and an arrangement of semiconductor IC chips in the non-contact type IC card.

[Explanation of symbols]

2: electronic circuit board, 20: semiconductor IC chip, 20a:
Connection terminal, 21: circuit pattern, 22: connection circuit, 22
b, 22c: branch circuit, 21a: start point (end point), 21
b: end point (end point), 23: circuit substrate (substrate), 24: underfill material, 27: bonding wire.

Continued on the front page (72) Inventor Hironobu Ishizaka 1150 Goshonomiya, Shimodate-shi, Ibaraki Prefecture Within the Goshonomiya Works of Hitachi Chemical Co., Ltd. Within the Enterprise Server Division (72) Inventor Masao Sekibata 1 Horiyamashita, Hadano-shi, Kanagawa F-term (reference), Enterprise Server Division, Hitachi, Ltd. 5B035 AA08 AA11 BA03 BA05 BB09 CA01 CA03 CA06 CA08 CA23 CA31 5E338 AA12 BB63 BB75 CC01 CD32 EE27

Claims (3)

[Claims] 1. A semiconductor IC chip, a circuit pattern,
A connection circuit communicating from an end point of the circuit pattern to a connection terminal of the semiconductor IC chip is provided on the base material, and the semiconductor IC chip is mounted on the base material via an underfill material in a face-down state. In the electronic circuit board, the connection circuit has a branch circuit branched outside the periphery of the underfill material, and the branch circuits are wired so as to communicate with the connection terminals from different directions. An electronic circuit board, characterized in that: 2. A semiconductor IC chip, a circuit pattern,
A connection circuit communicating from an end point of the circuit pattern to a connection terminal of the semiconductor IC chip is provided on the base material, and the semiconductor IC chip is mounted on the base material via an underfill material in a face-down state. A circuit terminal for connecting the connection circuit and the connection terminal to at least two edges of the semiconductor IC chip, and being exposed outside a peripheral portion of the underfill material. An electronic circuit board, comprising: 3. A semiconductor IC chip, a circuit pattern,
A connection circuit communicating from an end point of the circuit pattern to a connection terminal of the semiconductor IC chip, on the base material, wherein the semiconductor IC chip is mounted on the base material via a bonding wire in a face-up state. In the electronic circuit board, the connection circuit is branched outside the periphery of the semiconductor IC chip, and a circuit terminal for connecting the connection circuit and the bonding wire is provided outside the periphery of the semiconductor IC chip. An electronic circuit board, wherein the bonding wire for connecting the circuit terminal and the connection terminal is provided so as to extend over an edge of the semiconductor IC chip.