JP2000183209A - Electric circuit device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent conduction between adjacent terminals for achieving high density mounting or miniaturization. SOLUTION: Plural first terminals 2 are formed on the surface of a first base material 3 so as to be radially widened, and second terminals 4 are formed on the surface of a second base material 5 so as to face the first terminals 2. Then, the first base material 3 is adhered to the second base material 5 in a state in which anisotropic conductive adhesive 6 is interposed. In this case, the anisotropic conductive adhesive 6 is moved in the Fr direction, and the terminals 2 and 4 are formed so as to widen in radial direction so that conduction between the adjutant terminals can be prevented. Also, high density mounting or miniaturization can be attained by forming the plural terminals 2 and 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a plurality of first terminals formed on a first base and a plurality of second terminals formed on a second base.
The present invention relates to an electric circuit device in which terminals are electrically connected with an anisotropic conductive adhesive, and a method for manufacturing the electric circuit device.

[0002]

2. Description of the Related Art Conventionally, a technique of connecting a large number of terminals formed on the surfaces of two substrates through an anisotropic conductive adhesive has been used in various electric circuit devices. .

FIG. 5 shows an example of the structure of such an electric circuit device disclosed in Japanese Patent Publication No. 61-174643, in which (a) is a plan view and (b) is a plan view. (a)
It is a BB end elevation.

The electric circuit device 50 includes a bare chip (referred to as an unpackaged semiconductor device) 5 as a base material.
3 and a circuit board 55. A large number of projecting terminals (hereinafter referred to as “bumps”) 52 are formed on the outer periphery of the surface of the bare chip 53. Are formed. The bare chip 53 and the circuit board 55 are mechanically bonded by an anisotropic conductive adhesive 6, and each bump 52 and each electrode terminal 54 are electrically connected by conductive particles 6 a included in the anisotropic conductive adhesive 6. Have been.

Next, a method for mounting the bare chip 53 on the circuit board 55 will be described.

To mount the bare chip 53 on the circuit board 55, first, a paste-like anisotropic conductive adhesive 6 is applied to the circuit board 55, or a film-like anisotropic conductive adhesive 6 is applied.
Paste.

[0007] Then, the bare chip 53 and the circuit board 55 are aligned, and pressure and heat are applied. As a result, the anisotropic conductive adhesive 6 is dissolved and cured in a state of being filled in the gap between the bare chip 53 and the circuit board 55, and the mechanical bonding between the bare chip 53 and the circuit board 55 as described above, and The conduction between the bump 52 and each electrode terminal 54 is achieved.

The connection technique using an anisotropic conductive adhesive as described above is frequently used when a bare chip is mounted at a high density on an electronic circuit board. Specifically, a liquid crystal device (a bare chip) is used. (A case where a driving IC is mounted on a glass substrate by COG) or an MCM (multi-chip module) of a mobile terminal such as a mobile phone or a mobile computer.

[0009]

As described above, the anisotropic conductive adhesive 6 is applied to the bare chip 53 and the circuit board 5 as described above.
Pressing while heating while sandwiching between 5 and
Since the anisotropic conductive adhesive 6 has fluidity, it moves radially outward from the center of the bare chip 53. At this time, the number of the conductive particles 6a sandwiched between the bump 52 and the electrode terminal 54 and contributing to the conduction between the bump 52 and the electrode terminal 54 decreases, and the connection resistance between the bump 52 and the electrode terminal 54 increases. There was a problem. For example, in the case of conductive particles obtained by plating Ni / Au on plastic particles having a particle size of 5 μm, the connection resistance per one is about 1Ω, and the conductive particles 6a sandwiched between the bump 52 and the electrode terminal 54 are If the number is five or less, the connection resistance becomes larger than 0.2Ω. In the case of a bare chip for driving a high-definition display, or a bare chip for an MPU or ASIC for a computer, the number of input / output pins of the bare chip becomes very large and the cross-sectional area of the terminal itself becomes small. In, the above-mentioned problem becomes remarkable.

On the other hand, as a method for solving such a problem, the conductive particles 6a sandwiched between the bumps 52 and the electrode terminals 54 using an anisotropic conductive adhesive 6 having a high density of the conductive particles 6a are used. There are ways to increase the number. However, if the content density of the conductive particles 6a is high, the conductive particles 6a moving radially as described above may cause conduction between adjacent bumps.

In order to keep the connection resistance between the bump 52 and the electrode terminal 54 low and to prevent conduction between adjacent bumps, an anisotropic conductive adhesive having a high density of the conductive particles 6a is used. 6 may be used only in a small amount, but in this case, a gap is formed between the bare chip 53 and the circuit board 55 where the adhesive 6 is not filled, and the mechanical connection between the two becomes weak. was there.

Another problem is that the bare chip 53
When the coefficient of thermal expansion of the circuit board 55 differs from that of the circuit board 55, the bare chip 53 and the circuit board 55 are relatively displaced by the heat applied when connecting them, and the bump 52 and the electrode terminal 5 are displaced.
There was also a risk that the relative position with respect to No. 4 would shift, resulting in poor connection. For example, the coefficient of thermal expansion of the bare chip 53 is 3p
pm (= 3 × 10 ⁻⁶ ), and the circuit board 55 is a printed circuit board made of glass epoxy and has a coefficient of thermal expansion of 20 pp.
m (= 20 × 10 ⁻⁶ ) and the size of the bare chip 53 is 1
If it is 0 mm × 10 mm and these temperatures are increased by 65 ° C., a maximum deviation of 7 μm will occur.

Accordingly, an object of the present invention is to provide an electric circuit device capable of high-density mounting and miniaturization.

Another object of the present invention is to provide an electric circuit device which can avoid conduction between adjacent terminals.

Another object of the present invention is to provide an electric circuit device capable of reducing the connection resistance between terminals.

Still another object of the present invention is to provide an electric circuit device which strengthens the mechanical connection between the substrates.

Another object of the present invention is to provide an electric circuit device for preventing a connection failure between terminals.

Still another object of the present invention is to provide a method for manufacturing an electric circuit device for manufacturing the above-described electric circuit device.

[0019]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a first terminal having a plurality of first terminals.
A base material, a second base material having a plurality of second terminals formed so as to face the plurality of first terminals, and a plurality of the first terminals and the second terminals containing a large number of conductive particles; An anisotropic conductive adhesive interposed between the first terminals and the second terminals to individually conduct the respective first terminals and the second terminals, wherein the plurality of first terminals are the first base material Is formed to spread radially on the surface of the
The terminal is formed so as to spread radially on the surface of the second base material.

Further, the present invention provides at least one of a first base member having a plurality of first terminals and a second base member having a plurality of second terminals formed so as to face the plurality of first terminals. Adhering an anisotropic conductive adhesive to the first substrate and positioning the first base and the second base with a predetermined distance therebetween so that each first terminal and each second terminal face each other. In a method for manufacturing an electric circuit device, comprising the steps of: pressing, heating, and bonding these substrates, the plurality of first terminals are formed so as to radially spread on the surface of the first substrate. The plurality of second terminals are formed so as to radially spread on the surface of the second base material.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
An embodiment of the present invention will be described. Here, FIG.
1 is a diagram showing an embodiment of an electric circuit device according to the present invention, (a) is a plan view, and (b) is an AA end view of (a). FIG. 2 is a plan view showing another embodiment of the electric circuit device according to the present invention, and FIG. 3 is a plan view showing still another embodiment of the electric circuit device according to the present invention. . FIG. 4 is a diagram for explaining a method of manufacturing the electric circuit device shown in FIG.

The electric circuit device 1 according to the present invention includes a first base member 3 having a plurality of first terminals 2 and a second base member 5 having a plurality of second terminals 4. The plurality of first terminals 2 are formed so as to radially spread on the surface of the first base material 3, and the plurality of second terminals 4 are spread radially on the surface of the second base material 5. Is formed. Further, each of the first terminals 2 and each of the second terminals 4 are formed so as to face each other, and an anisotropic conductive adhesive 6 is provided between the first terminals 2 and the second terminals 4. It is interposed.
The anisotropic conductive adhesive 6 contains a large number of conductive particles 6a, and these conductive particles 6a
And each of the second terminals 4 are individually brought into conduction.

Here, "to make each first terminal 2 and each second terminal 4 individually conductive" means to make a pair of first terminals 2 and second terminals 4 arranged to face each other conductive. Let
This means that the terminal is not electrically connected to another terminal adjacent along the surface of the base material.

The expression "arranged so as to spread radially" means that an arbitrary point C (preferably a point substantially at the center of the first base material 3 and hereinafter referred to as "base point C") is radially centered. Considering a plurality of virtual lines D (hereinafter referred to as “radiation D”) extending to the first terminal 2 and the second terminal 4
Mean that the first terminal 2 and the second terminal 4 are arranged on the line of the radiation D, and the circumferential interval Eθ (the terminal centered on the base point C) When a circle R on which the circles 2 and 4 are arranged is imagined, the distance between the first terminals 2 and the distance between the second terminals 4 adjacent to each other on the virtual circle is the distance from the base point C. It increases in proportion to.

The conductive particles 6a in the anisotropic conductive adhesive move radially in the Fr direction when the first base material 3 and the second base material 5 are bonded as described later (FIG. 4). (c)
), The content density increases as the distance from the base point C increases, and if the circumferential interval Eθ is small, the accumulated conductive particles 6a can be placed between adjacent terminals (first terminals adjacent in the surface direction of the base material). (Or between the second terminals). Therefore, the circumferential interval Eθ needs to be an interval at which the conductive particles 6a are not accumulated (hereinafter, the minimum value of the circumferential interval Eθ at which the conductive particles 6a are not accumulated is referred to as a “critical interval”). . That is, in order to make the circumferential interval Eθ near the base point C equal to or longer than the critical interval, not only the terminals 2 and 4 are arranged to spread radially, but also the angle θ between the adjacent radiations D is The terminals on the adjacent virtual line (for example, one first terminal 2a disposed on one radiation and the first terminal 2b disposed on the radiation adjacent to the radiation,
The terminal closest to the terminal 2a) must be at an angle such that the conductive particles 6a do not conduct.

Note that if all the circumferential intervals Eθ are equal to or greater than the critical interval, * for all the radiations D, even if the angles θ between the adjacent radiations D are equal as shown in FIGS. Even if they are not equal, the radial distances Er (meaning the distance between the first terminals 2 and the distance between the second terminals 4 adjacent to each other on the radiation) are all as shown in FIGS. Terminal 2,
4 or 12 and 14 are equally spaced (in other words, even if the virtual circles R where all the first terminals 2 and 12 and the second terminals 4 and 14 are arranged are concentric circles at equal intervals). * Even if the contact areas between the first terminals 2, 22 and the second terminals 4, 24 are all uniform (see FIGS. 1 and 3) or not (for example, As shown in FIG. 2, the contact area between the first terminal 12 and the second terminal 14 may be increased according to the distance from the base point C). Here, the conductive particles 6a
Is hardly moved in the illustrated Fθ direction when the first base material 3 and the second base material 5 are bonded to each other as described later.
Even if the radial intervals Er are equal as described above, conduction between terminals adjacent on the radiation can be avoided.

In addition, the above-mentioned critical distance becomes constant above a predetermined value (ie, if the circumferential distance Eθ becomes a predetermined value or more, the adjacent terminals 2a, 2a, 2a, 2b, 2b, 2b, 2b, 2b, 2b, 2b, 3b) regardless of the passing amount of the conductive particles 6a. As shown in FIG. 3, in the vicinity of the base point C, the distance Eθ in the circumferential direction becomes larger as the distance from the base point C increases, and the distance from the base point C exceeds a predetermined distance as shown in FIG. The distance may be constant (however, it is necessary to keep the critical interval or more).

The present invention can be applied to any electric circuit device provided with the terminals 2 and 4 and the substrates 3 and 5 as described above. For example, the present invention can be applied to a case where a bare chip (which means an unpackaged semiconductor device as described above) is mounted on a substrate. Specifically, in a liquid crystal device, a driving IC which is a bare chip is replaced with a liquid crystal element (Accurately, when mounting COG (chip-on-glass) on a glass substrate that is a component of a liquid crystal element), or when mounting a bare chip on a circuit board in a mobile terminal such as a mobile phone or a mobile computer. Applicable. In the above case, the liquid crystal device becomes the electric circuit device, the driving IC becomes the first base material, and the liquid crystal element becomes the second base material. In the above case, the portable terminal becomes the electric circuit device, the bare chip becomes the first base material, and the circuit board becomes the second base material.

The first terminal 2 is preferably a protruding electrode (bump). Further, the first terminal 2 is formed on one surface of the first base member 3, and the second terminal 4 is connected to the second base member 5.
Is preferably formed on one side. Further, examples of the second base member 5 include a glass substrate and a resin substrate.

Further, as the anisotropic conductive adhesive 6, a thermosetting type in the form of a film or paste can be used, and the particle size of the conductive particles 6a is preferably about 3 to 5 μm.

Next, a method of manufacturing the electric circuit device 1 will be described with reference to FIG.

First, the second terminals 4 are formed on the surface of the second base member 5 so as to spread radially (see FIG. 4A).

Next, an anisotropic conductive adhesive 6 is applied to at least one of the first base material 3 and the second base material 5 so that the first terminals 2 and the second terminals 4 face each other. 1st substrate 3 and 2nd
Positioning is performed with the base material 5 opened a predetermined distance (see FIG.
(b)). In order to attach the anisotropic conductive adhesive 6, if the anisotropic conductive adhesive 6 is in the form of a paste, apply it. If the anisotropic conductive adhesive 6 is in the form of a film, apply it. paste.

The amount of the anisotropic conductive adhesive 6 to be adhered in this manner is determined by the gap between the base materials (formed by the first base material 3 and the second base material 5 in a bonded state as described later). It is preferable that the base material 3 and 5 be pasted out of the base material gap when these base materials 3 and 5 are bonded together. Specifically, the thickness of the anisotropic conductive adhesive 6 to be adhered (that is, the thickness when the adhesive 6 is in the form of a film, and the thickness when the adhesive 6 is in the form of a paste) Means the dimension of the base material gap (in FIG.
, Which is larger than the sum of the height of the first terminal 2 and the height of the second terminal 4).

Thereafter, these substrates 3 and 5 are pressurized, heated and bonded. Thereby, the anisotropic conductive adhesive 6
As shown in FIG. 4 (c), together with the conductive particles 6a, a portion where the terminals 2 and 4 are not arranged (between the terminal rows) is radiated outward from the base point C in the Fr direction shown in the drawing. And a part thereof protrudes from the substrates 3 and 5. Then, the opposing terminals are electrically connected with the conductive particles 6a interposed therebetween, and the anisotropic conductive adhesive 6 itself is cured to mechanically connect the two substrates 3 and 5.

Next, effects of the present embodiment will be described.

According to the present embodiment, since the first terminal 2 and the second terminal 4 are arranged so as to spread radially,
The number of contacts can be increased as compared with the conventional structure.
As a result, high-density mounting becomes possible, and when the present invention is applied to a liquid crystal device, high definition can be achieved. Further, the size of the electric circuit device can be reduced by high-density mounting.

Further, according to the present embodiment, since the first terminal 2 and the second terminal 4 are arranged as described above,
Despite the movement of the conductive particles 6a during the bonding of the base material, it is possible to avoid conduction between the terminals adjacent to each other on the virtual circle.

Further, since the terminals adjacent to each other on the virtual circle can be prevented from conducting, the conductive particles 6a
Can be used, and the number of conductive particles 6a sandwiched between the terminals can be increased to lower the connection resistance between the terminals.

Further, since conduction between terminals adjacent to each other on the virtual circle can be avoided, the anisotropic conductive adhesive 6
Can be increased, and when the amount is increased, 2
There is almost no gap between the base materials 3 and 5 where the anisotropic conductive adhesive 6 is not filled, and the mechanical connection between the base materials 3 and 5 can be strengthened.

Further, the first terminal 2 and the second terminal 4
As shown in FIG. 2, when the contact area between the base materials 3 and 5 is increased in accordance with the distance from the base point C, the base materials 3 and 5 are relatively Even if the relative positions of the two terminals 12 and 14 are slightly displaced due to the deformation, the first terminal 12 and the second terminal 14 can be moved over the entire area (not only near the base point C but also apart from the base point C). Connection can be secured.

[0042]

As described above, according to the present invention,
Since the first terminal and the second terminal are arranged so as to radially spread, the number of contacts can be increased as compared with the conventional structure. As a result, high-density mounting becomes possible, and when the present invention is applied to a liquid crystal device, high definition can be achieved. Further, the size of the electric circuit device can be reduced by high-density mounting.

Further, according to the present invention, since the first terminal and the second terminal are arranged as described above, the terminals adjacent to each other are moved despite the movement of the conductive particles during the bonding of the base material. Can be avoided.

Furthermore, since conduction between adjacent terminals can be avoided, an anisotropic conductive adhesive having a high density of conductive particles can be used, and the number of conductive particles sandwiched between the terminals can be increased. The connection resistance between the terminals can be reduced.

Further, since conduction between the terminals adjacent to each other can be avoided, the amount of the anisotropic conductive adhesive used can be increased.
There are almost no voids in which the anisotropic conductive adhesive is not filled, and the mechanical connection between the two substrates can be strengthened.

Further, when the contact area between the first terminal and the second terminal is increased in accordance with the distance, the two substrates are relatively deformed by the heat applied when connecting the two substrates. Thus, even if the relative positions of the two terminals are slightly shifted, the connection between the first terminal and the second terminal can be secured in the entire area.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of an electric circuit device according to the present invention, wherein (a) is a plan view and (b) is an AA end view of (a).

FIG. 2 is a plan view showing another embodiment of the electric circuit device according to the present invention.

FIG. 3 is a plan view showing still another embodiment of the electric circuit device according to the present invention.

FIG. 4 is a diagram for explaining a method of manufacturing the electric circuit device shown in FIG.

5A and 5B are diagrams showing an example of the structure of a conventional electric circuit device, where FIG. 5A is a plan view, and FIG. 5B is a BB end view of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric circuit device 2 Projection electrode (1st terminal) 3 Drive IC (1st base material) 4 2nd terminal 5 Liquid crystal element (2nd base material) 6 Anisotropic conductive adhesive 6a Conductive particle C Base point (1st D) Virtual line θ Angle between adjacent virtual lines

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshimichi Ouchi 3-30-2 Shimomaruko, Tokyo, Japan Inside Canon Inc. (72) Inventor Yasushi Shioya 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (11)

[Claims] 1. A first base material having a plurality of first terminals, a second base material having a plurality of second terminals formed to face the plurality of first terminals, and a large number of conductive particles. And an anisotropic conductive adhesive interposed between the first terminal and the second terminal for individually conducting the first terminal and the second terminal. In the above, the plurality of first terminals are formed so as to radially spread on the surface of the first base material, and the plurality of second terminals are formed so as to radially spread on the surface of the second base material. An electric circuit device characterized by the above-mentioned. 2. The method according to claim 1, wherein the first terminal and the second terminal are arranged on a plurality of imaginary lines radially extending around a substantially center point of the first base. The electric circuit device according to claim 1. 3. The electric circuit device according to claim 2, wherein an angle between adjacent virtual lines is an angle such that the conductive particles do not conduct terminals on the adjacent virtual lines. . 4. The electric circuit device according to claim 2, wherein an angle between adjacent virtual lines is equal for all virtual lines. 5. The electric circuit device according to claim 2, wherein an interval between terminals adjacent to each other on the virtual line is equal for all terminals. 6. The electric circuit device according to claim 1, wherein contact areas between the first terminal and the second terminal are all uniform. 7. The method according to claim 2, wherein a contact area between the first terminal and the second terminal is increased according to a distance from a center of the plurality of virtual lines. The electric circuit device according to claim 1. 8. The electric circuit device according to claim 1, wherein the first base material is an unpackaged semiconductor device. 9. The electric circuit device according to claim 8, wherein the first base is a driving IC, and the second base is a liquid crystal element. 10. At least one of a first base material having a plurality of first terminals and a second base material having a plurality of second terminals formed so as to face the plurality of first terminals. A step of applying a conductive adhesive, a step of positioning the first base material and the second base material with a predetermined distance therebetween so that each first terminal and each second terminal face each other, Pressurizing, heating and bonding the base material of the electric circuit device, wherein the plurality of first terminals are formed so as to radially spread on the surface of the first base material, and The plurality of second terminals are:
A method for manufacturing an electric circuit device, wherein the electric circuit device is formed so as to radially spread on a surface of the second base material. 11. The amount of the anisotropic conductive adhesive to be attached to at least one of the first base and the second base depends on the first base and the second base in a bonded state. The method for manufacturing an electric circuit device according to claim 10, wherein the amount is larger than a gap to be formed.