JPH07231010A - Structure and method for connecting interconnecting substrate - Google Patents

Abstract

PURPOSE:To reduce the pressure load and prevent poor continuity of terminal connection parts by reducing the pressure dispersion at connection of connecting terminals through anisotropic conductive rubber connectors in a terminal connection of electronic parts on one interconnecting substrate with those on other substrate. CONSTITUTION:An interconnecting substrate 1 having nearly flat connecting terminals 3 to be connected to other interconnecting substrate 2 comprises protrusions 5 on the terminals 3. The terminals 3 having the protrusions 5 and nearly flat connecting terminals 4 of the other substrate 2 are pressed through anisotropic conductive rubber connectors 6 to thereby connect through point contacts of the connectors 6 with the protrusions 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a connecting portion of a wiring pattern of a wiring board to an electronic component (another wiring board, a semiconductor chip, etc.) and another wiring board or a semiconductor chip to the connecting portion. The present invention relates to a connecting structure and a connecting method using an anisotropic conductive rubber connector with the electronic component.

[0002]

2. Description of the Related Art Generally, one wiring board is connected to another wiring board, or an LSI (Large Scale Int) is used.
As one of the methods for mounting a semiconductor chip such as an emulsion (large-scale integrated circuit), there is a structure in which an anisotropic conductive rubber connector is interposed between the connection terminals to connect the terminals by crimping.

FIG. 6 shows an example of a connection state between conventional wiring boards 51 and 52, in which flat connection terminals 5 having wiring patterns formed on the wiring boards 51 and 52, respectively.
3, 53, 54, 54 are connected to each other by sandwiching a sheet-shaped anisotropic conductive rubber connector 55 between them and holding them in a crimped state from above and below by a press-fastening tool (not shown) so that they are electrically connected to each other. ing.

[0004]

In such a connection,
Since the surfaces of the connection terminals 53, 53, 54, 54 of the wiring boards 51, 52 connected via the anisotropic conductive rubber connector 55 are flat, the contact with the anisotropic conductive rubber connector 55 is a surface contact. Thus, the pressure is dispersed, and poor conduction is likely to occur, and a large amount of pressure load is required to prevent the poor conduction.

Therefore, an object of the present invention is to reduce the pressure dispersion when connecting the connection terminals via the anisotropic conductive rubber connector to concentrate the pressure and reduce the pressurizing load, and It is an object of the present invention to provide a wiring board connection structure and a connection method capable of preventing conduction failure.

[0006]

In order to solve the above problems, the invention according to claim 1 connects a wiring board and another electronic component such as another wiring board by means of connection terminals which are substantially flat to each other. In the connection structure of the wiring board, a plurality of projections are provided on the substantially flat connection terminal on the side of at least one member of the wiring board and the other electronic component, and one of the plurality of projections is provided. The configuration is characterized in that the substantially flat connection terminal on the member side and the substantially flat connection terminal on the other member side are connected via an anisotropic conductive rubber connector.

According to a second aspect of the present invention, there is provided a wiring board connecting method for connecting a wiring board and another electronic component such as another wiring board by means of substantially flat connection terminals to each other. And a plurality of protrusions on at least one member side of the other electronic components of the substantially flat connection terminal, the substantially flat connection terminal on the one member side provided with the plurality of protrusions, An anisotropic conductive rubber connector is provided between the other member and the substantially flat connection terminal, and the connection terminals are connected through the protrusion and the anisotropic conductive rubber connector by applying pressure. It is characterized by connecting the.

[0008]

According to the present invention, a plurality of protrusions are provided on a substantially flat connection terminal on at least one member side of the wiring board and the other electronic component, and a substantially flat connection terminal on the other member side. Since the connection is made by pressing through the anisotropic conductive rubber connector, it is possible to obtain a reliable conductive state by contacting what was conventionally in contact with the surface at the point of the protrusion.
Moreover, since the pressing force is concentrated on the points due to the protrusions, the pressure distribution is small, and the pressing load becomes lighter than in the conventional case where the surface contact is required.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a wiring board connection structure and connection method according to the present invention will be described below with reference to FIGS.

First, FIG. 1 shows a method of connecting wiring boards to each other as an example to which the present invention is applied. Reference numerals 1 and 2 are wiring boards, 3 and 4 are connection terminals, and 5 is a protrusion (ball bump). ), 6 are anisotropic conductive rubber connectors. The wiring boards 1 and 2 may be either a hard board made of ceramic or glass epoxy, or a flexible film board made of polyimide or another resin.

For example, a wiring pattern (not shown) having a predetermined pattern formed by plating copper (Cu) foil or Cu with gold (Au) on the surfaces of the hard wiring boards 1 and 2 made of glass epoxy and almost corresponding to each other. Flat connection terminals 3, 3, 4, 4 are formed respectively. The wiring pattern and the connection terminals 3, 3, 4, 4 usually have a film thickness of about 10 to 30 μm.

In the embodiment, a plurality of ball bumps 5, 5, 5, ... As protrusions are provided on the upper surfaces of the connection terminals 3, 3 of one (lower side in the figure) wiring board 1. There is. To form the ball bump 5, as shown in FIG. 2, a tube body 11 used for wire bonding is used, and the tip of the Au wire 12 passing through the tube body 11 is melted 12a by heating to form a connection terminal. This is done by successively attaching the ball bumps 5 to the upper surface of 3. The ball bumps 5 have a height (diameter) of about 50 to 100 μm or a maximum of about 100 μm.

Thus, the plurality of ball bumps 5, 5, 5,
As shown in FIG. 3, the sheet-shaped anisotropic conductive rubber connector 6 is placed on the connection terminals 3 and 3 to which the ... Are attached, respectively. This anisotropic conductive rubber connector 6 is usually about 0.5
It has a thickness of about m, has conductivity in the thickness direction, and has insulation in the longitudinal direction (direction along the surface). The connection terminals 4 and 4 of the other wiring board 2 are respectively placed on the connection terminals 3 and 3 on which the anisotropic conductive rubber connector 6 is thus placed.

That is, as shown in FIG. 4, the respective ball bumps 5, 5, 5 are provided on the connection terminals 3, 3 of the wiring board 1.
, 5, 5, 5, and the anisotropic conductive rubber connector 6 are interposed, the connection terminals 4, 4 of the wiring board 2 are overlapped, and these are connected between the upper and lower crimping plates 41, 42 which form a clamping tool. It is put in and pressed. At this time, the anisotropic conductive rubber connector 6
Are corrugated by the ball bumps 5, 5, 5, ..., 5, 5, 5, ..., Therefore, the anisotropic conductive rubber connector 6 and the ball bumps 5, 5 are connected between the connection terminals 3, 3 and the connection terminals 4, 4. 5, 5, ..., 5, 5, 5 ,.

Therefore, the pressing force applied to the wiring boards 1 and 2 by the pressing tools (pressing plates 41 and 42) is
Since the ball bumps 5, 5, 5, ..., 5, 5, 5, ... need only be concentrated on the anisotropic conductive rubber connector 6 portion,
Compared with the conventional method that requires surface contact between the connection terminals, the pressure is less dispersed and the pressure is concentrated, so that the load can be reduced.

By the way, in the above embodiment, the ball bumps 5, 5, 5 are provided on the connection terminals 3 of the one wiring board 1, but in contrast to the embodiments, the connection terminals 4 of the other wiring board 2 are provided.
Ball bumps may be provided on the top. Furthermore, ball bumps may be provided on the connection terminals 3 and 4 of both wiring boards 1 and 2, that is, the connection terminals 3 of one wiring board 1 may be provided.
The ball bumps 5, 5, 5 may be provided on the upper side, and the ball bump may be provided on the connection terminal 4 of the other wiring substrate 2. The point is that a plurality of ball bumps should be provided on the connection terminals of at least one wiring board.

FIG. 5 shows an embodiment in which ball bumps are provided on the connection terminals 3 and 4 of both wiring boards 1 and 2, respectively. That is, in this embodiment, similarly to the above-described embodiments, the connection terminals 3 of the wiring board 1 on one side (lower side in the drawing)
A plurality of ball bumps 5, 5, 5, ... Are provided on the upper surface of 3, and the ball bumps 7, 7, ... On the lower surface of the connection terminals 4, 4 of the other (upper side in the drawing) wiring board 2.
Are provided for each. In the illustrated example,
The other ball bumps 7, 7, 7, ... Are respectively located between the one ball bumps 5, 5, 5 ,.

Therefore, in substantially the same manner as in the above-described embodiment, the anisotropically stacked ball bumps 5, 5, 5, ..., 5, 5, 5, ... On the connection terminals 3, 3 of the wiring board 1. The ball bumps 7, 7, ..., 7, 7, ... Under the connection terminals 4, 4 of the wiring board 2 are superposed on the conductive rubber connector 6, and these are clamped (pressing plates 41, 42). ) And pressurize it. As a result, the anisotropic conductive rubber connector 6 has the ball bumps 5, 5, 5, ..., 5, 5, 5 ,.
, And the ball bumps 7, 7, ..., 7, 7, ... Between them, the connection terminals 3, 3 and the connection terminals 4, 4 are connected to each other by the anisotropic conductive rubber connector 6 and the ball bumps 5, 5.
5, 5, ..., 5, 5, 5, ... And ball bumps 7, 7, ..., 7, 7 ,.

Although the wiring boards are connected to each other in the above embodiments, the present invention is not limited to this. For example, the wiring boards of electronic parts such as LSI and other semiconductor chips are connected to the wiring boards. Built-in or liquid crystal display (LC
D: Liquid Crystal Display)
(Indium Tin Oxi) of the glass substrate of
de: TAB (Tape Autom) to transparent conductive film
It may be a connection of a carrier tape of aged bonding).

Further, in the embodiment, the projection (ball bump) on the connection terminal is formed by ball bonding of wire bonding, but the projection may be formed by another method. For example, a solder ball is used as the connection terminal. It may be a protrusion placed on top. Further, the shape of the wiring pattern, the application of the present invention, and the like are arbitrary, and, of course, the specific detailed structure and the like can be appropriately changed.

[0021]

As described above, according to the wiring board connection structure and the connection method of the present invention, a plurality of wiring boards and a plurality of electronic components are provided on a substantially flat connection terminal on at least one member side. Since the protrusion was provided and the connection was made by pressing through the anisotropically-conductive rubber connector with the almost flat connection terminal on the other member side, what was conventionally contacted on the surface was contacted at the point by the protrusion. Therefore, a reliable conduction state can be obtained. Moreover, since the pressure force is concentrated on the points due to the protrusions, the pressure distribution is less than in the conventional case where surface contact is required, which makes it possible to reduce the pressure load and minimize it. it can.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing how to connect wiring boards to each other as an example to which the present invention is applied.

FIG. 2 is an enlarged cross-sectional view showing an example of formation of a protrusion on a connection terminal to which the present invention is applied.

FIG. 3 is a vertical cross-sectional side view showing a state in which an anisotropic conductive rubber connector is placed on a connection terminal provided with a protrusion according to the present invention.

FIG. 4 is a vertical cross-sectional side view showing a pressure-bonded state by pressurizing connection of wiring boards according to the present invention by forming a protrusion on one connection terminal.

FIG. 5 is a vertical cross-sectional side view showing a pressure-bonded state by pressurizing the connection between wiring boards according to the present invention by forming protrusions on both connection terminals.

FIG. 6 is a vertical cross-sectional side view showing an example of a connection state of conventional wiring boards.

[Explanation of symbols]

 1, 2 Wiring board 3, 4 Connection terminal 5 Projection (ball bump) 6, 7 Anisotropic conductive rubber connector

Claims (2)

[Claims] 1. A connection structure of a wiring board for connecting a wiring board and another electronic component to each other by substantially flat connection terminals, wherein the substantially flat connection is made on at least one member side of the wiring substrate and the other electronic component. A plurality of projections are provided on the connection terminal, and the substantially flat connection terminal on one member side provided with the plurality of projections and the substantially flat connection terminal on the other member side are anisotropically conductive. A wiring board connection structure characterized by being connected via a flexible rubber connector. 2. A wiring board connecting method for connecting a wiring board and another electronic component to each other by substantially flat connecting terminals, wherein the wiring board and the other electronic component are provided on the side of at least one of the other electronic components. A plurality of protrusions is provided on the connection terminal, and a difference is provided between the substantially flat connection terminal on the one member side on which the plurality of protrusions are provided and the substantially flat connection terminal on the other member side. A method of connecting wiring boards, characterized in that the connection terminals are connected to each other via the protrusion and the anisotropic conductive rubber connector by interposing an anisotropic conductive rubber connector and applying pressure.