KR20090068886A - Connecting structure using anisotropic conductive film and checking method of connecting condition thereof - Google Patents

Abstract

A connection structure body using an anisotropy conductive film and a connection state testing method thereof are provided to easily test an electric connection state between the first and second electrodes without respect to a kind of a member to be connected through two electrically divided second electrodes and a dummy electrode. The second member to be connected has a plurality of second electrodes. The second electrode is electrically divided into two. A dummy electrode(300) is symmetrically protruded in the divided end of the second electrode facing both ends of the first electrode(150). An anisotropy conductive film(400) is interposed between the first member to be connected and the second member to be connected. The anisotropy conductive film connects the first member to be connected with the second member to be connected.

Description

CONNECTING STRUCTURE USING ANISOTROPIC CONDUCTIVE FILM AND CHECKING METHOD OF CONNECTING CONDITION THEREOF}

The present invention relates to a bonded structure using an anisotropic conductive film, and more particularly to a connection structure of a bonded structure using an anisotropic conductive film by a simple configuration, an anisotropic conductive can improve the quality and reliability A connection structure using a film and a method for inspecting the connection state thereof.

In general, an anisotropic conductive film (ACF) is a film-shaped adhesive in which conductive particles such as metal-coated plastic or metal particles are dispersed, and the member is made of a special material to be connected or a fine pitch of signal wiring. It has been widely used in electrical adhesive connection, such as when the and members cannot be attached by soldering.

The anisotropic conductive film as described above is typically used as a connecting material for packaging a liquid crystal display panel (LCD), a printed circuit board (PCB) and a driver IC circuit in the LCD module.

For example, a plurality of driver ICs are mounted in the LCD module to drive TFT (Thin Film Transistor) patterns. The driver IC is largely mounted on the LCD panel through a COG (Chip On Glass) mounting method, which is a method of mounting the LCD panel in a gate area and a data area without a separate structure, and a tape carrier package (TCP) equipped with a driver IC. It is divided into TAB (Tape Automated Bonding) mounting method, which indirectly mounts a driver IC in the gate area and data area of the panel.

By the way, since the electrode on the driver IC element side and the electrode on the LCD panel side are formed at minute pitch intervals, it is difficult to use means such as soldering even if any mounting method is employed. For this reason, anisotropic conductive films are mainly used to electrically connect the electrodes on the driver IC side and the electrodes on the panel side.

1 is a plan view illustrating an LCD module employing a general TAB method, FIG. 2 is a cross-sectional view taken along line AA of the embodiment of FIG. 1, and FIG. 3 is connected from an anisotropic conductive film taken along line BB of the embodiment of FIG. 1. It is a block diagram which shows the state which removed and expanded the member, FIG. 4 is sectional drawing which shows the favorable connection state of the anisotropic conductive film, and FIG. 5 is sectional drawing which shows the poor connection state of the anisotropic conductive film.

1 and 2, the source side printed circuit board 10 for transmitting an external signal to the LCD panel 20 is positioned in the row direction of the LCD panel 20, and the driver IC 31 is mounted. TCP 30 is electrically connected between the LCD panel 20 and the printed circuit board 10. In this case, between the LCD panel 20 and the TCP 30, the TCP 30 and the printed circuit board 10 are connected by an anisotropic conductive film 40.

As shown in FIGS. 2 and 3, the anisotropic conductive film 40 is formed by dispersing a plurality of conductive particles 42 in the insulating adhesive 41, and is connected to each other by opposing the members by thermally crimping them between the connected members. The electrically-conductive particle 42 contacts between the terminals of (10, 30), and makes electrical connection. At this time, insulation is maintained on the x-y plane and conduction is conducted in the z-axis direction.

More specifically, as shown in FIG. 4, between the TCP 30 and the printed circuit board 10 or the TCP 30 and the LCD panel 20, which are members to be connected, are dispersed in the insulating adhesive 41. An anisotropic conductive film 40 composed of a plurality of conductive particles 42 is interposed. After pressurization (about 2 to 3 MPa) with a predetermined temperature (about 160 to 180 ° C.) for about 10 to 20 seconds, between the electrodes 12 and 32 formed to face each of the connected members 10 and 30, respectively. The electrically conductive particles 42 are interposed to electrically connect the members 10 and 30 to each other.

However, as shown in FIG. 5, the electrical connection between the members 10 and 30 by the anisotropic conductive film 40 may be poor. For this reason, the plurality of conductive particles 42 dispersed in the insulating adhesive 41 of the anisotropic conductive film 40 is arranged unevenly, or the conductive particles 42 are opposed to the connected members 10 and 30 when pressed. It may not be interposed between the formed electrodes 12 and 32. In addition, even when the pressure is not uniformly applied over the entire surface of the member 10, 30 to be connected, even if the conductive particles 42 are interposed between the electrodes 12, 32, the electrodes 12, 32 may not come into contact with each other. have.

Therefore, there is a need to inspect the electrical connection state between the members 10 and 30 to be connected by the anisotropic conductive film 40, and despite the defect, it is possible to prevent the material loss by the continuous progress of the subsequent process, It can improve the reliability and quality.

As a method for inspecting the connection state of a bonded structure using an anisotropic conductive film, there are conventionally a method of observing with a microscope, a method of capturing an image through a camera and analyzing the image accordingly. In addition, there are methods for checking and analyzing unevenness between the connected members 10 and 30 by measuring indentation and surface roughness.

As mentioned above, the connection state inspection method of the bonded structure using the conventional anisotropic conductive film has constraints, such as that a to-be-connected member should be transparent when using a naked eye or a microscope or a camera, and checks an indentation or surface roughness In this case, since a complicated inspection apparatus must be used, there are problems such as restrictions on installation and an increase in manufacturing cost.

In addition, as described above, the conventional inspection method indirectly measures the connection state between the members to be connected, so that it is impossible to completely confirm whether the connection is actually made. Therefore, there is a problem of deteriorating reliability and quality.

An object of the present invention devised to solve the above problems is an anisotropy that can easily inspect the connection state of the connection structure of the circuit board using the anisotropic conductive film by a simple configuration, and improve the quality and reliability It is providing the bonded structure using the electrically conductive film, and its connection state test | inspection method.

In order to achieve the above object, the bonded structure using the anisotropic conductive film of the present invention includes a first to-be-connected member having a plurality of first electrodes arranged side by side on one surface and facing one surface of the first to-be-connected member. A second to-be-connected member arranged on the surface to face the plurality of first electrodes, the second connected member having a plurality of second electrodes electrically separated from each other, and facing both ends of the plurality of first electrodes; A dummy electrode protruding from each other at a distal end of each of the plurality of second electrodes so as to be symmetrical with each other, and interposed between the first connected member and the second connected member to connect the first connected member and the second connected member. It consists of an anisotropic conductive film made to make.

In addition, the first to-be-connected member and the second to-be-connected member may each be any one selected from a printed circuit board and a flexible circuit board.

In addition, the dummy electrode may be separated from the plurality of second electrodes when the dummy electrode receives a tension of a predetermined load or more from the outside.

In addition, the anisotropic conductive film includes a plurality of conductive particles dispersed in an insulating adhesive, the insulating adhesive bonds the first and second connected members, and the plurality of conductive particles are the plurality of conductive particles. Pressing between the first electrode and the second electrode is characterized in that for electrically connecting the plurality of first electrode and the second electrode.

On the other hand, in the connection state inspection method of the bonded structure using the anisotropic conductive film of this invention, the ACF attachment step of attaching an anisotropic conductive film to one surface of the 1st to-be-connected member provided with the some 1st electrode, and the said 1st blood The second to-be-connected member and the first to-be-connected member, each of which is arranged to face the one surface of the connection member to face the plurality of first electrodes, each of which has a plurality of second electrodes electrically separated from each other. Aligning the connected member to be aligned facing each other, ACF thermocompression bonding the first and second connected members by applying heat and pressure to the anisotropic conductive film, and both ends of the plurality of first electrodes And a connection state inspection step of inspecting whether each of the dummy electrodes protruding from each other to be symmetrical with each other at the separated ends of the plurality of second electrodes facing each other is electrically connected. Achieved.

In addition, the connection state is performed after the step of checking, characterized in that it further comprises a warning step notifying the outside in case of a bad connection.

The method may further include a dummy electrode separation step of separating the dummy electrodes from the plurality of second electrodes in the case of the connection goodness, after the connection state inspection step.

In addition, the first to-be-connected member and the second to-be-connected member may each be any one selected from a printed circuit board and a flexible circuit board.

The bonded structure using the anisotropic conductive film and the method for inspecting the connected state thereof according to the present invention are not limited to the type of the member to be connected through the simple configuration of the second electrode and the dummy electrode electrically separated into two, The electrical connection state of the second electrode can be easily inspected.

In addition, reliability and quality can be improved by directly inspecting the electrical connection state between the plurality of first electrodes and the second electrodes, respectively.

In addition, when the connection state is good, the dummy electrode can be separated from the second electrode to secure the excellent appearance.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the bonded structure using an anisotropic conductive film according to the present invention.

6 is an exploded perspective view showing a preferred embodiment of a bonded structure using an anisotropic conductive film according to the present invention, Figure 7 is a combined perspective view of the embodiment of Figure 6, Figure 8 is a cross-sectional view taken along line CC of the embodiment of Figure 7 to be.

The connection structure using the anisotropic conductive film which concerns on this invention is the thing provided with the 1st to-be-connected member 100 provided with the 1st electrode 150, and the 2nd electrode 250 as shown in FIGS. 2 includes the member 200 to be connected, the dummy electrode 300 and the anisotropic conductive film 400. The first to-be-connected member 100 and the second to-be-connected member 200 may be a printed circuit board or a flexible circuit board, and the anisotropic conductive film 400 may include an insulating adhesive 410 and conductive particles 420. Include.

As illustrated in FIGS. 6 and 7, the first connected member 100 includes a plurality of first electrodes 150 arranged side by side on one surface thereof. The first to-be-connected member 100 is a member that is interconnected through the second to-be-connected member 200 and the anisotropic conductive film 400, which will be described later, and includes a printed circuit board (PCB) or a flexible circuit board ( FCP, Flexible Printed Circuit. In this case, a plurality of first electrodes 150 arranged side by side as connection terminals are provided on one surface of the circuit board, which is the first connected member 100.

As shown in FIGS. 6 and 7, the second to-be-connected member 200 is arranged to face the one surface of the first to-be-connected member 100 to face the plurality of first electrodes 150, respectively. Each has a plurality of second electrodes 250 that are electrically separated into two. The second to-be-connected member 200 is a member that is interconnected with the first to-be-connected member 100, and may be a printed circuit board or a flexible circuit board like the first to-be-connected member 100. In this case, the circuit board, which is the second to-be-connected member 200, is arranged to face each of the plurality of first electrodes 150 as a connection terminal to a surface facing one surface of the first to-be-connected member 100. A plurality of second electrodes 250 are provided.

As shown in FIG. 8, each of the plurality of second electrodes 250 is electrically separated into two pieces, which are formed by the conductive particles 420 included in the anisotropic conductive film 400 to be described later. ) And the second electrode 250 to easily check whether they are electrically connected. As illustrated in FIGS. 6 to 8, the second electrodes 250 are physically spaced apart from each other, and in this case, the second electrodes 250 are also electrically separated from each other. That is, although not shown in the drawing, even if each of the plurality of second electrodes 250 is a single body, if it is connected through a material such as an insulator in the middle, it will be regarded as two electrically separated. .

As shown in FIGS. 6 to 8, the dummy electrode 300 protrudes to be symmetrical with each other at separate ends of each of the plurality of second electrodes 250 facing both ends of the plurality of first electrodes 150. do. The separated ends of the plurality of second electrodes 250 may be inspected to be electrically connected to the first electrode 150 by using a device capable of confirming whether electricity is supplied, such as an ammeter or a galvanometer. However, the second electrode 250 is located inside the second to-be-connected member 250 so that it is not easily found or the mistake of judging the first electrode 150 as the second electrode 250 is prevented in advance. In order to more easily include the dummy electrode 300. In this case, the dummy electrode 300 should not be in contact with the adjacent dummy electrode 300, and it is convenient for the test to bend the protruding portion to be in contact with the side of the second connected member 200. Therefore, the electrical connection between the first electrode 150 and the second electrode 250 can be confirmed only through the dummy electrode 300. Meanwhile, the dummy electrode 300 may be separated from the plurality of second electrodes 250 when the dummy electrode 300 receives a tension greater than a predetermined load from the outside. This removes the dummy electrode 300, which may seem messy in appearance after the inspection is completed, and has an effect of making the appearance beautiful. When the first dummy electrode 300 is formed on the second electrode 250, the dummy electrode 300 should be attached so that the dummy electrode 300 does not easily fall off during transportation, manufacture, and inspection. However, after the inspection is completed, the user can easily remove the dummy electrode 300 from the second electrode 250 by hand or by using a work tool, from the pre-formed coupling force between the dummy electrode 300 and the second electrode 250. Some amount of tension is required to separate. As described above, the tension for detaching from the pre-formed bonding force means a tension above a predetermined load.

As shown in FIG. 7, the anisotropic conductive film 400 is interposed between the first to-be-connected member 100 and the second to-be-connected member 200, so that the first to-be-connected member 100 and the second to-be-connected object are separated. The connection member 200 is connected. More specifically, the anisotropic conductive film 400 includes a plurality of conductive particles 420 dispersed in the insulating adhesive 410, as shown in FIG. In this case, the insulating adhesive 410 adheres the first to-be-connected member 100 and the second to-be-connected member 200, and the plurality of conductive particles 420 may be connected to the plurality of first electrodes 150. Pressurized between the second electrodes 250 to electrically connect the plurality of first electrodes 150 and the second electrodes 250. As a result, as shown in FIG. 8, the conductive particles 420 are electrically connected to the first electrode 150 from the separated one of the second electrodes 250, and again, the conductive particles from the first electrode 150. It is electrically connected to the other separated one of the second electrode 250 via the 420. As a result, the first electrode 150 and the second electrode 250 are completely connected. However, when a connection failure occurs in the conductive particles 420 interposed between the first electrode 150 and the second electrode 250, it may not be electrically connected through the dummy electrode 300.

Hereinafter, the preferable Example of the connection state inspection method of the bonded structure using the anisotropic conductive film which concerns on this invention is described.

9 is a block diagram showing a first embodiment of a connection state inspection method of a bonded structure using an anisotropic conductive film according to the present invention, Figure 10 is a connection state inspection method of a bonded structure using an anisotropic conductive film according to the present invention 11 is a block diagram showing a second embodiment of the present invention, and FIG. 11 is a block diagram showing a third embodiment of a connection state inspection method for a bonded structure using an anisotropic conductive film according to the present invention.

However, description overlapping with the connection structure using the anisotropic conductive film which concerns on this invention is abbreviate | omitted, and it demonstrates with reference to FIGS. 6-8.

Connection state inspection method of the bonded structure using an anisotropic conductive film according to the present invention is as shown in Figure 9 to 11 ACF attachment step (S101), connected member alignment step (S201), ACF thermocompression step (S301) and It includes a connection state check step (S401). In addition, it may further include a warning step (S501) and the dummy electrode separation step (S601).

In the ACF attaching step (S101), the anisotropic conductive film (ACF) is attached to one surface of the first to-be-connected member 100 having the plurality of first electrodes 150 shown in FIG. 6. Attaching the anisotropic conductive film (ACF) to the first to-be-connected member 100 is to press the anisotropic conductive film (ACF) to the first to-be-connected member 100 before the main compression in the ACF thermocompression step (S201) to be described later. It is attached to the good. Accordingly, the second to-be-connected member 200 is adhered to the first to-be-connected member 100 through an anisotropic conductive film ACF in the ACF thermocompression step S201 to be described later. Therefore, it is necessary to align the first to-be-connected member 100 and the second to-be-connected member 200 to face each other before main compression.

Alignment of the connected member (S201) is arranged so as to face each of the plurality of first electrodes 150 on a surface facing one surface of the first connected member 100, each of the plurality of electrically separated The second to-be-connected member 200 having the second electrode 250 and the first to-be-connected member 100 are aligned to face each other. That is, the plurality of first electrodes 150 provided in the first connected member 100 and the plurality of second electrodes 250 provided in the second connected member 200 must be aligned to face each other.

In the ACF thermocompression bonding step S301, heat and pressure are applied to the anisotropic conductive film 400 to bond the first to-be-connected member 100 and the second to-be-connected member 200. As shown in FIG. 8, the anisotropic conductive film 400 includes a plurality of conductive particles 420 dispersed in the insulating adhesive 410. In this case, the insulating adhesive 410 adheres the first to-be-connected member 100 and the second to-be-connected member 200, and the plurality of conductive particles 420 may be connected to the plurality of first electrodes 150. Pressurized between the second electrodes 250 to electrically connect the plurality of first electrodes 150 and the second electrodes 250.

In the connection state inspection step (S401), each of the dummy electrodes 300 protruding from each other so as to be symmetrical to each other at the separated ends of the plurality of second electrodes 250 facing both ends of the plurality of first electrodes 150 may be electrically connected. Check if it is connected. In this case, it is possible to directly check whether the first electrode 150 and the second electrode 250 are electrically connected by using electronic equipment such as an ammeter or a galvanometer for the mutually symmetrical dummy electrodes 300.

On the other hand, the warning step (S501) is performed after the connection state check step (S401), and informs the outside in case of a bad connection. That is, if the current signal inspected through the dummy electrode 300 is not transmitted, the electrical connection by the conductive particles 420 interposed between the first electrode 150 and the second electrode 250 will be deteriorated. Therefore, it is necessary to confirm the connection failure state to the outside. In this case, a warning sound using a speaker or a siren or a warning light that can visually warn the user may inform the external user of the connection failure.

In addition, the dummy electrode separation step S601 is performed after the connection state inspection step S501, and when the connection is good, the dummy electrode 300 is separated from the plurality of second electrodes 250, respectively. This removes the dummy electrode 300, which may seem messy in appearance after the inspection is completed, and has an effect of making the appearance beautiful.

The embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical idea of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention, as will be apparent to those skilled in the art.

1 is a plan view showing an LCD module employing a general TAB method,

2 is a cross-sectional view taken along the line A-A of the embodiment of FIG.

3 is a configuration diagram showing a state in which the connected member is separated and expanded from the anisotropic conductive film along the line B-B of the embodiment of FIG. 1,

4 is a cross-sectional view showing a good connection state of the anisotropic conductive film,

5 is a cross-sectional view showing a poor connection state of the anisotropic conductive film,

6 is an exploded perspective view showing a preferred embodiment of a bonded structure using an anisotropic conductive film according to the present invention,

7 is a combined perspective view of the embodiment of FIG. 6,

8 is a cross-sectional view taken along the line C-C of the embodiment of FIG.

9 is a block diagram showing a first embodiment of a connection state inspection method for a bonded structure using an anisotropic conductive film according to the present invention;

10 is a block diagram showing a second embodiment of a connection state inspection method for a bonded structure using an anisotropic conductive film according to the present invention;

Fig. 11 is a block diagram showing a third embodiment of the connection state inspection method for a bonded structure using the anisotropic conductive film according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100: first connected member

150: first electrode

200: second connected member

250: second electrode

300: dummy electrode

400: anisotropic conductive film (ACF)

410: insulating adhesive

420: conductive particles

Claims (8)

A first to-be-connected member having a plurality of first electrodes arranged side by side on one surface, A second to-be-connected member arranged on a surface of the first to-be-connected member to face the plurality of first electrodes, the second to-be-connected member having a plurality of electrically separated second electrodes, respectively; Dummy electrodes protruding from the ends of each of the plurality of second electrodes facing the ends of the plurality of first electrodes to be symmetric with each other; A connection structure using an anisotropic conductive film comprising an anisotropic conductive film interposed between the first to-be-connected member and the second to-be-connected member to connect the first to-be-connected member and the second to-be-connected member. The method of claim 1, And the first to-be-connected member and the second to-be-connected member are each one selected from a printed circuit board and a flexible circuit board. The method of claim 1, The dummy electrode may be separated from the plurality of second electrodes when the dummy electrode receives a tension or more from a predetermined load from the outside. The method of claim 1, The anisotropic conductive film includes a plurality of conductive particles dispersed in an insulating adhesive, The insulating adhesive bonds the first to-be-connected member and the second to-be-connected member, The plurality of conductive particles are pressed between the plurality of first electrodes and the second electrode to electrically connect the plurality of first electrodes and the second electrode, characterized in that the bonded structure using an anisotropic conductive film. An ACF attaching step of attaching the anisotropic conductive film to one surface of the first to-be-connected member having a plurality of first electrodes, A second to-be-connected member and the first to be arranged on a surface of the first to-be-connected member to face the plurality of first electrodes, each having a plurality of second electrodes that are electrically separated from each other; Arranging the connected members so as to face the connected members; An ACF thermocompression bonding step of adhering the first to-be-connected member and the second to-be-connected member by applying heat and pressure to the anisotropic conductive film; An anisotropic conductivity comprising a connection state inspection step of inspecting whether each of the dummy electrodes protruding from each other so as to be symmetrical to each other at each end of each of the plurality of second electrodes facing each other of the plurality of first electrodes is electrically connected; Method for inspecting the connection state of a bonded structure using a film. The method of claim 5, The connection state inspection method of the bonded structure using an anisotropic conductive film, characterized in that it is carried out after the connection state inspection step, further comprising a warning step to notify the outside in case of a connection failure. The method of claim 5, And a dummy electrode separation step of separating the dummy electrodes from the plurality of second electrodes, respectively, after the connection state inspection step. Condition checking method. The method of claim 5, And each of the first to-be-connected member and the second to-be-connected member is any one selected from a printed circuit board and a flexible circuit board.

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