JP2001094250A - Method of connecting flexible wiring board and manufacture of electro-optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of connecting a flexible wiring board and a method of manufacturing an electro-optical device which facilitates connecting to a work at a high accuracy and simplifies module process steps. SOLUTION: The method of connecting a flexible wiring board to a work comprises step a) of detecting regions for connecting terminals (output terminal regions 235A) of the flexible wiring board 23 on wiring bond regions 26A of the work (liquid crystalline panel), step b) of placing positioning members 100 for positioning the output terminal regions 235A on the regions detected in step a) for bonding the output terminal regions 235A, step c) of setting the output terminal regions 235A at specified positions, using the positioning members 100, step d) of temporarily fixing the output terminal regions 235A positioned in step c) by pressure-welding an anisotropically conductive film, etc., and step e) of bonding the output terminal regions 235A to the wiring bond regions 26A after removing the positioning members 100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for connecting a flexible wiring board suitable for a liquid crystal device such as a liquid crystal display device, an electro-optical device such as an EL (electroluminescence) display device, and a method for manufacturing an electro-optical device. .

[0002]

2. Description of the Related Art In recent years, display devices have been widely used as information display terminals for portable devices, homes, offices / factories, automobiles, and the like. In particular, the liquid crystal display device has features such as thinness, light weight, low voltage, and low power consumption. For example, a liquid crystal display device is a main component of an electronic display, and its application to a PDA (personal portable information terminal) or the like has been increasingly active by utilizing low power consumption.

As a conventional liquid crystal display device, for example, there is a liquid crystal display device 1 of a passive matrix drive system as shown in FIG. This liquid crystal display device 1 has a liquid crystal panel 2 and a printed circuit board 3. The liquid crystal panel 2 and the printed board 3 are electrically connected via the first and second flexible wiring boards 4 and 5.

[0004] The liquid crystal panel 2 has a pair of glass substrates 6 and 7 arranged opposite to each other. Between these glass substrates 6 and 7, a sealing material (not shown) interposed so as to go around the display area is arranged. The gap formed between the glass substrates 6 and 7 and the sealing material includes
The liquid crystal is sealed. On the surface of the glass substrate 6 that faces the glass substrate 7 (the surface facing the glass substrate 6),
The plurality of signal electrodes 8 are formed so as to be parallel.
On the other hand, a plurality of scanning electrodes 9 are formed on the surface of the glass substrate 7 facing the glass substrate 6 (the surface facing the glass substrate 7) along a direction orthogonal to the signal electrodes 8.

At a predetermined side edge of the liquid crystal panel 2 (a lower edge in FIG. 10), the edge of the glass substrate 6 projects laterally (downward in the figure) from the edge of the glass substrate 7. The projection (the glass substrate 6 is the glass substrate 7
(A region that does not overlap with) constitutes the wiring junction region 6A. Further, at a side edge portion (left side edge portion in the figure) adjacent to the above-described side edge portion of the liquid crystal panel 2, the edge portion of the other glass substrate 7 is more lateral than the edge portion of the one glass substrate 6 (see FIG. (Middle, left) so as to constitute the wiring junction region 7A. Then, signal driver ICs 10 and 11 are mounted on the wiring bonding area 6A on the glass substrate 6 side by COG (Chip On).
Glass) implemented. Driver IC for these signals
Reference numerals 10 and 11 are connected to an output terminal portion 8A in which the plurality of signal electrodes 8 extend and an input terminal portion 12 arranged on the edge side of the wiring junction region 6A. Further, a scanning driver IC 13 is provided in the wiring joint area 7A of the glass substrate 7 with CO.
G is implemented. The scanning driver IC 13 is connected to an output terminal 9A in which the plurality of scanning electrodes 9 extend and an input terminal 14 arranged on the edge side of the wiring joint region 7A.

The output side terminal portion 4 A of the first flexible wiring board 4 is connected to the wiring bonding area 6 of the glass substrate 6.
It is joined via an anisotropic conductive film (ACF) so as to be electrically connected to the plurality of input terminal portions 12 arranged along the long side of A. Similarly, the output-side terminal portion 5A of the second flexible wiring board 5 is electrically connected to the plurality of input terminal portions 14 arranged along the long side of the wiring bonding region 7A of the glass substrate 7. They are joined via an anisotropic conductive film so as to be connected. The input-side terminal portion 4B of the first flexible wiring board 4 is joined to the output terminal section 15 formed on the printed circuit board 3 via an anisotropic conductive film or a connector. The input terminal portion 5B of the second flexible wiring board 5 is
It is joined to an output terminal portion 16 formed on the printed circuit board 3 via an anisotropic conductive film or a connector. The printed circuit board 3 is provided with predetermined wiring and various electronic components for controlling and driving the liquid crystal panel 2.

As an electronic apparatus using the liquid crystal display device having the above-described configuration, there is an electronic apparatus having an input unit such as a keyboard and a numeric keypad, and displaying data on a liquid crystal panel in accordance with an input operation to the input unit. In such an electronic device, a liquid crystal panel and a printed circuit board are incorporated in a chassis (panel storage frame). At this time, make sure that the printed circuit board is located behind the liquid crystal panel.
One flexible wiring board is bent.

[0008]

In the liquid crystal display device 1 described above, the first flexible wiring board 4 connected to the wiring bonding area 6A of one glass substrate 6 on which the signal driver ICs 10 and 11 are mounted; Scan driver IC
13 is the wiring bonding area 7 of the other glass substrate 7
It is necessary to connect the second flexible wiring board 5 connected to A to the printed circuit board 3 independently of each other.
For this reason, there is a problem that the module process is complicated and lacks convenience.

Further, each flexible wiring board 4
And 5 are separately connected to the printed circuit board 3, it is not desirable that the output terminal portions 15 and 16 arranged on the printed circuit board 3 are close to each other. That is, when the flexible wiring boards 4 and 5 are joined to the printed board 3 using the mounting machine, it is necessary to secure a distance that does not cause interference between the flexible wiring boards. in this way,
The use of a plurality of, for example, two flexible wiring boards is a factor preventing the printed circuit board 3 from being downsized.

Further, in the liquid crystal display device 1 having the above-described structure, the width dimension x1 for mounting the scanning driver IC 13 and the output terminal portion 5A of the flexible wiring substrate 5 are provided in the wiring bonding region 7A of the glass substrate 7. It is necessary to ensure a predetermined bonding margin x2 for bonding and a dimension x3 for separating the scanning driver IC 13 and the output-side terminal portion 5A of the flexible wiring board 5. For this reason, as the width dimension of the liquid crystal panel 2 becomes shorter,
The ratio of the area occupied by the display region with respect to the entire surface becomes smaller. Therefore, there is a demand that the display area of a housing such as a chassis for accommodating the display device be maximized by reducing the wiring junction region of the liquid crystal panel.

An object of the present invention is to provide a method for connecting a flexible wiring board, which can easily and accurately connect to a member to be bonded and can simplify a module process.

Another object of the present invention is to provide a method for manufacturing an electro-optical device which can be assembled in a simple and high-precision module process using the method for connecting a flexible wiring board according to the present invention.

[0013]

A method for connecting a flexible wiring board according to the present invention is a method for connecting a flexible wiring board to an object to be bonded.
(E).

(A) a step of detecting a region where the terminal portion of the flexible wiring board is bonded in the wiring bonding region of the body to be bonded; and (b) detecting the terminal portion detected in the step (a). A step of arranging a positioning member for determining the position of the terminal portion in a region to be joined; (c) a step of arranging the terminal portion at a predetermined position by the positioning member; and (d) positioning in the step (c). (E) temporarily removing the positioning member, and then joining the terminal portion to the wiring joining region.

A method for manufacturing an electro-optical device according to the present invention comprises:
A manufacturing method including a step of connecting a flexible wiring board to an electro-optical panel, wherein the electro-optical device includes an electro-optical panel having a first substrate and a second substrate facing each other; The substrate has a first wiring bonding region that does not overlap with the second substrate, and the second substrate has a second wiring bonding region that does not overlap with the first substrate, The flexible wiring board includes a substrate main body, a branch wiring portion provided by branching from the substrate main body, a first output-side terminal region provided on the substrate main body, and a second wiring portion provided on the branch wiring portion. 2), and includes the following steps (A) and (B), wherein (A) the first output-side terminal area of the flexible wiring board includes: Connected to the first wiring junction region; and (B) The second output terminal area of the flexible wiring board is connected to the second wiring bonding area, and the step (B) includes the following steps (a) to (e). .

(A) In the second wiring junction region,
Detecting a region of the flexible printed circuit board to which the second output terminal region is joined; and (b) detecting a region of the flexible wiring board where the second output terminal region is joined, which is detected in the step (a). Arranging a positioning member for determining the position of the second output terminal area; (c) arranging the second output terminal area at a predetermined position by the positioning member; and (d) the step. (C) temporarily fixing the second output-side terminal area positioned in (c), and (e) removing the positioning member, and then transferring the second output-side terminal area to the second wiring joint area. Join.

According to the method for connecting a flexible wiring board and the method for manufacturing an electro-optical device according to the present invention, the following main operational effects are obtained. Since these main functions and effects are common to both, the terms in the latter method of manufacturing an electro-optical device are described in parentheses, and common descriptions are omitted.

According to the method for connecting a flexible wiring board and the method for manufacturing an electro-optical device according to the present invention, the terminal portion (second output terminal area) of the flexible wiring board can be positioned using a positioning member. Therefore, the terminal portion (second output side terminal region) can be easily joined with high accuracy. The reason will be described below. Since the terminal portion (the second output terminal region) is quite flexible, its free end is easy to move and handling is difficult. However, since the terminal portion (second output side terminal region) can be temporarily fixed after being positioned at a predetermined position while guiding the terminal portion (second output side terminal region) by the positioning member, the terminal portion (second output side terminal region) can be accurately and easily formed. It can be joined to a predetermined position while positioning at a predetermined position.

The positioning member may be provided in a device for temporarily fixing the terminal portion in the step (d), for example, a device for crimping an anisotropic conductive film. In this configuration, since a dedicated device for the positioning member is not required, the manufacturing method and the manufacturing device can be further simplified.
The positioning member is desirably provided so as to be movable so that its position can be finely adjusted. further,
It is preferable that the positioning member is formed of a substantially U-shaped frame member having one end opened. According to this configuration, the terminal portion (the second output-side terminal region) can be accurately positioned at a predetermined position while guiding the terminal portion. The shape of the positioning member is not particularly limited as long as the position of the terminal portion (second output terminal region) can be specified. For example, the positioning member may have a configuration other than the above-described continuous frame member, for example, a discontinuous frame or a claw-shaped member.

Further, according to the method of manufacturing the electro-optical device of the present invention, the first flexible wiring board is used to make the first
In addition, since the connection with the second region to be joined becomes possible, the convenience of the flexible wiring board can be improved.

In the method of manufacturing an electro-optical device according to the present invention, the following aspects can be taken.

In the flexible wiring board, it is preferable that the arrangement direction of the wiring in the first output terminal area is the same as the arrangement direction of the wiring in the second output terminal area.

According to this structure, the flexible wiring board includes both the substrate body and the branch wiring portion, the first and second flexible wiring boards.
Can be joined in one direction (X direction or Y direction), so that the terminal connection step can be facilitated. Further, according to this configuration, the branch wiring portion can be bonded to one wiring bonding region, for example, a short side of the second wiring bonding region.
Since it is not necessary to allow the flexible wiring board to be joined or folded on the long side of the wiring connection region, the width of the short side of the second wiring connection region can be reduced. This contributes to effective use of the display area.

In the flexible wiring board, the first output terminal area is provided on one surface of the substrate main body, and the second output terminal area is provided with the first output terminal area. It is desirable to be provided on the surface opposite to the surface provided.

According to this configuration, for example, when the flexible wiring board of the present invention is applied to an electro-optical panel, the opposing surfaces of the first substrate and the second substrate constituting the electro-optical panel The output side terminal regions of the flexible wiring board can be connected to the terminals formed respectively. Therefore, according to this configuration, the number of components of the flexible wiring board can be reduced, and the joint between the object to be bonded (the electro-optical panel) and the flexible wiring board can be easily performed.

The shape, layer structure, and wiring structure of the flexible wiring board of the present invention are set in accordance with the structure and wiring structure of the object. For example, the branch wiring section includes:
It is desirable that the substrate bends and extends substantially in an L shape from the substrate body. Further, it is preferable that the branch wiring portion has an end located before an end of the substrate body. According to this configuration, the substrate main body and the branch wiring portion can be joined to each other in different regions of the joined object while being integrated.

According to this structure, the flexible wiring board includes both the substrate body and the branch wiring portion in the first and second wiring sections.
Can be joined in one direction (X direction or Y direction), so that the terminal connection step can be facilitated. Further, according to this configuration, the branch wiring portion can be bonded to one wiring bonding region, for example, a short side of the second wiring bonding region.
Since it is not necessary to allow the flexible wiring board to be joined or folded on the long side of the wiring connection region, the width of the short side of the second wiring connection region can be reduced. This contributes to effective use of the display area.

In the above electro-optical device, the electro-optical panel may have an electro-optical material layer. The electro-optic material is not particularly limited, and various electro-optic materials such as liquid crystal and electroluminescence can be selected.

In the electro-optical device, a signal wiring is provided in the first output side terminal area provided on the substrate body of the flexible wiring board, and the second wiring provided on the branch wiring portion. It is desirable that a scanning wiring be provided in the output terminal area. This configuration is effective for a color electro-optical device that requires more signal electrodes than scanning electrodes.

Further, in the electro-optical device, a semiconductor device, for example, a driver IC may be provided in at least one of the first wiring junction region and the second wiring junction region.
Can be mounted.

Further, according to the method of manufacturing an electro-optical device according to the present invention, since the method includes the flexible wiring board according to the present invention, the assembly can be performed by a simple module process and the yield is good.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of a method for connecting a flexible wiring board according to the present invention and a method for manufacturing an electro-optical device using the same will be described with reference to the drawings.

(Electro-Optical Device) First, an electro-optical device formed by applying the method for connecting a flexible wiring board according to the present invention will be described.

FIGS. 1 and 2 show an example in which an electro-optical device to which the manufacturing method according to the present invention is applied is applied to a reflection type liquid crystal display device of a passive matrix driving system. FIG. 1 is a plan view schematically showing the liquid crystal display device according to the present embodiment, and FIG. 2 is an enlarged plan view showing a part of the liquid crystal display device shown in FIG.

The liquid crystal display device 20 according to the present embodiment
As shown in FIG. 1, a liquid crystal panel (electro-optical panel) 21
And a flexible wiring board 2 connected to a first substrate 25 and a second substrate 26 constituting the liquid crystal panel 21.
3 and a printed circuit board 24 connected to the flexible wiring board 23.

First, the liquid crystal panel 21 will be described.

The liquid crystal panel 21 has a first substrate 25 and a second substrate 26 which are arranged to face each other. Between these first and second substrates 25 and 26,
A sealing material (not shown) is arranged so as to go around the display area. Then, these first and second substrates 25, 2
A liquid crystal layer (not shown) is sealed in a region formed by 6 and the sealing material. First and second substrates 25, 26
Is composed of, for example, a glass substrate, a plastic substrate, or the like.

The surface of the first substrate 25,
A plurality of signal electrodes 27 are arranged in parallel on a surface facing the substrate 26 (hereinafter referred to as a “facing surface of the first substrate 25”). The signal electrode 27 is made of a conductive material having transparency with respect to display light, for example, ITO (Indi).
um Tin Oxide). These signal electrodes 2
Reference numerals 7 are arranged at predetermined intervals from each other along a predetermined direction (X direction in FIG. 1). On the other hand, a plurality of scanning electrodes 28 are provided on the surface of the second substrate 26 on the side facing the first substrate 25 (hereinafter, this surface is referred to as the “facing surface of the second substrate 26”). Are located. These scanning electrodes 28 are formed of a conductive material that reflects display light, for example, a metal. Also, these scanning electrodes 28
Along a predetermined direction (Y direction in FIG. 1), they are arranged in parallel at a predetermined interval from each other. That is, the first
The plurality of signal electrodes 27 formed on the substrate 25 and the plurality of scanning electrodes 28 formed on the second substrate 26 are orthogonal to each other via a liquid crystal layer or the like (including an alignment film not shown),
A so-called XY matrix is configured.

The liquid crystal panel 21 has two adjacent
The side has a first wiring bonding region 25A and a second wiring bonding region 26A. First wiring junction region 25A
In the lower part of FIG. 1, the edge of the first substrate 25 is
The first substrate 25 is formed on an opposing surface that does not overlap with the second substrate 26 so as to protrude from an edge of the substrate 26.
In the second wiring bonding region 26A, on the left side of FIG. 1, the edge of the second substrate 26 protrudes from the edge of the first substrate 25, and the second substrate 26 overlaps the first substrate 25. It is formed on the opposite surface that does not have to be.

A signal driver (X driver) IC2 is provided in the first wiring joint region 25A of the first substrate 25.
9 and 30 are implemented. The mounting method of these signal driver ICs 29 and 30 is not particularly limited, but is mounted by, for example, a COG (Chip On Glass) method. These signal driver ICs 29 and 30 include a terminal portion 27 </ b> A connected to the signal electrode 27 and a first substrate 25.
And the bonding terminal portion 31 arranged on the long side of the first wiring bonding region 25A. The signal driver ICs 29 and 30 are connected to the terminal 2 of the signal line 27, respectively.
7A and the bonding terminal portion 31 are flip-chip mounted by, for example, face-down.

On the other hand, as shown in an enlarged manner in FIG. 2, a scanning driver IC 32 is mounted, for example, by COG on the second wiring joint region 26A of the second substrate 26. The scanning driver IC 32 is connected to the terminal portions 28A of the plurality of scanning electrodes 28 and the plurality of joining terminal portions 33.
Then, the scanning driver IC 32 is flip-chip mounted, for example, by face-down on the terminal portion 28A of the scanning electrode 28 and the joint terminal portion 33. Furthermore, the joint terminal 33 is arranged so as to be routed in the second wiring joint region 26A, and the input terminal 33A extends to the end on the flexible wiring board 23 side.

As described above, in the present embodiment, in the second wiring bonding region 26A, the bonding terminal 33 is
It is preferable that the input side terminal portion 33A is arranged so as to extend in a direction orthogonal to the scanning electrodes 28, that is, in a direction parallel to the signal electrodes 27. By arranging the joining terminal portions 33 in this manner, the flexible wiring board 23 is joined on the short side of the second wiring joining region 26A. Therefore, unlike the conventional example shown in FIG. 10, the dimension x3 for separating the scanning driver IC 13 from the output terminal 5A of the flexible substrate 5 and the amount of folding required for bending the flexible substrate 5 are not required. . As a result, the area ratio of the display area to the entire surface of the liquid crystal panel 21 can be further increased.

Next, the flexible wiring board will be described. FIG. 3 is a plan view schematically showing an example of the flexible wiring board 23 applied to the connection method according to the present invention.

The flexible wiring board 23 is formed on both sides of a flexible board 231 made of, for example, an electrically insulating resin, that is, a plurality of signal wirings 232, a plurality of scanning wirings 233, and other parts formed as necessary. (Not shown).

The flexible wiring board 23 has a board body 234 having a long end having a width dimension (indicated by a symbol L1 in FIG. 3), an L-shaped branch from one side of the board body 234, and forward. A short branch wiring portion 235 having a protruding width dimension (indicated by a symbol L2 in FIG. 3);
4 and an input wiring portion 236 projecting rearward (rightward in FIG. 3) from the rear portion. The front end (left side in FIG. 3) of the substrate main body 234 constitutes a first output terminal area 234A, and the front end of the branch wiring part 235 constitutes a second output terminal area 235A. The end of the input wiring portion 236 forms an input terminal region 236A.

The signal wiring 232 is formed in a predetermined pattern in the input wiring portion 236 and the substrate main body 234. The scanning wiring 233 is formed in a predetermined pattern in the input wiring part 236, the substrate main body 234, and the branch wiring part 235.

The layer structure of the flexible wiring board 23 is not particularly limited, and may have a known structure. FIG. 4 shows an example of the layer structure of the flexible wiring board 23. FIG. 4 shows A in FIG.
The cross section along the -A line is shown schematically. In the present embodiment, the first output-side terminal area 234A and the input-side terminal area 236A are formed on one surface (the upper surface in FIG. 3) of the flexible substrate 231 and the scanning wiring 233 is provided on one side of the flexible substrate 231. Formed on the surface. The second output-side terminal region 235A is formed on the other surface (the lower surface in FIG. 3) of the flexible substrate 231. The scanning wiring 233 is connected to the flexible substrate 2.
31 are formed continuously from the upper surface to the lower surface. That is, as shown in FIG. 3 and FIG.
A wiring 233A for upper surface scanning formed on the upper surface of the flexible substrate 231, a wiring 233B for lower surface scanning formed on the lower surface of the flexible substrate 231, and a wiring 233A for upper surface scanning and a wiring 233B for lower surface scanning, respectively. And a contact layer 233C to be connected. Further, flexible and insulating protective layers 237 and 238 are formed on the upper and lower surfaces of the flexible substrate 231 to protect the signal wiring 232 and the scanning wiring 233, respectively. The protective layer 237
It has been removed in the first output terminal area 234A,
The signal wiring 232 is connected to the bonding terminal 31 disposed on the first substrate 25. Similarly, the protective layer 238 has been removed in the second output-side terminal area 235A, and the scanning wiring 233 is connected to the joint terminal 33 disposed on the second substrate 26.

As described above, in the flexible wiring board 23 in the present embodiment, the first output terminal area 234A is formed on one surface of the flexible substrate 231 and the second output terminal area 235A is formed on the other surface. Have been. Then, as shown in FIG. 1, the first output side terminal region 234
A is bonded at a first wiring bonding region 25A of the first substrate 25, a second output terminal region 235A is bonded at a second wiring bonding region 26A of the second substrate 26, and the input terminal The area 236A is the printed circuit board 24
Is joined to.

The printed circuit board 24 is, as shown in FIG.
For example, it has a wiring circuit on which various electronic components 241 such as a power supply IC are mounted. And the printed circuit board 24
Is the input terminal area 236 of the flexible wiring board 23
A and the signal wiring 232 and the scanning wiring 2
33 has a connection portion 242 electrically connected thereto.

(Method of Connecting Flexible Wiring Board, Method of Manufacturing Liquid Crystal Display) Next, an example of a method of connecting the flexible wiring board 23 having such a configuration to the liquid crystal panel 21, that is, an example of a method of manufacturing the liquid crystal display will be described. I do.

(A) First, as shown in FIG. 1, the first output terminal area 234A of the flexible wiring board 23 is
The first wiring joint region 25A of the first substrate 25 is joined via an anisotropic conductive film (ACF) (not shown). In this step, the signal wiring 232 of the first output terminal area 234A and the bonding terminal 31 of the first wiring bonding area 25A are electrically connected.

(B) Next, the flexible wiring board 23
The second output side terminal region 235A formed in the branch wiring portion 235 of the second substrate 26 and the second wiring joint region 26 of the second substrate 26
A is joined via an anisotropic conductive film (not shown).

This step (B) further includes the following steps (a) to (e). The sequence of this step is shown in FIG.
Symbols a to e shown in FIG. 5 correspond to the symbols of the following steps.

(A) First, in the second wiring bonding area 26A, the area where the second output terminal area 235A of the flexible wiring board 23 is bonded is detected.

In this step, the second wiring joint area 26A of the liquid crystal panel 21 is detected by a known optical method. Similarly, the second output side terminal area 235A of the flexible wiring board 23 is detected by a known optical method. Based on the detected data, the second substrate 26
In the second wiring junction region 26A, the branch wiring portion 23
The position where the fifth second output terminal area 235A is located is specified.

Preferably, this step (a) further includes a step of detecting a wiring pattern formed in the second output terminal area 235A of the flexible wiring board 23.

(B) Next, positioning for determining the position of the second output terminal area 235A is performed in the area where the second output terminal area 235A is joined, which is detected in the step (a). The member 100 is arranged.

In this step, for example, as shown in FIG.
The positioning member 100 is arranged at a predetermined position (the position specified in the step (a)) of the second wiring joint region 26A of the second substrate 26.

The shape of the positioning member 100 is not particularly limited as long as the position of the second output terminal region 235A, that is, the end of the branch wiring portion 235 can be specified. For example,
The positioning member 100 may be a continuous frame member, a discontinuous frame member, or a claw-shaped member.
In this example, the positioning member 100 is a frame member having a substantially U-shaped plane.

The positioning member 100 may be provided on a movable device only for achieving this step, but may be provided on another device, for example, a device for thermocompression bonding an anisotropic conductive film. It may be.

(C) Then, the second output terminal area 235A is arranged at a predetermined position by the positioning member 100.

In this example, the positioning member 100 is a frame member having a substantially U-shaped plane. Then, the end of the branch wiring portion 235 where the second output-side terminal region 235A is formed is inserted from the open end of the positioning member 100. The positioning of the second output-side terminal region 235A is performed by positioning the end of the branch wiring portion 235 with the positioning member 100.
This is achieved by further moving the distal end of the branch wiring portion 235 until it comes into contact with the side plate 120 in a state of being inserted from the open end and guided by the side plates 110 and 110 facing each other. According to the positioning member 100, since the planar formation is substantially U-shaped, the second output side terminal region 2 is formed.
The end of the branch wiring portion 235 having 35A is positioned smoothly and accurately.

(D) Next, the second output side terminal region 235A positioned in the step (c) is anisotropically conductive between the second wiring junction region 26A and the end of the branch wiring portion 235. The temporary sheet (not shown) is temporarily fixed (temporarily pressed) by pressing. In this step, the anisotropic conductive film is heated at, for example, 50 to 60C.

(E) Next, the positioning member 100 is moved to the second
The second output side terminal region 235A is bonded (finally bonded) to the second wiring bonding region 26A by heating and pressing the anisotropic conductive film at, for example, 180 to 220 [deg.] C. after being separated from the substrate 26 of FIG. .

In this embodiment, the positioning member 100
Is provided, for example, as shown in FIG. 6 so as to be located outside the thermocompression bonding section 130 of the anisotropic conductive film compression device 150. The positioning member 100 can be provided so as to be able to move forward and backward with respect to the second substrate 26 by being configured to be relatively movable with respect to the thermocompression bonding section 130. The thermocompression bonding section 130 is configured to be able to bond at least the second output-side terminal area 235A. FIG. 6 is a view showing the positioning member 100 of the crimping device 160 and the end surface of the heat crimping unit 130, and details of the moving unit and the like are not shown.

In this step, by using the positioning member 100, the second output terminal area 235A of the branch wiring section 235 can be easily and accurately joined to a predetermined position. In this step, the second output terminal area 2
35A scanning wiring 233 and second wiring bonding area 26
The connection terminal 33 of A (input side terminal 33A) is electrically connected.

(C) Next, the flexible wiring board 23
The input terminal area 236A of the input wiring section 236 is connected to the connection section 242 of the printed circuit board 24 via an anisotropic conductive film (not shown).

(D) Next, if necessary, the printed circuit board 24 is bent at the position indicated by a chain line a in FIG.
Can be arranged on the back side.

Next, main functions and effects of the method of manufacturing the liquid crystal display device according to the present embodiment will be described.

According to the present embodiment, as described above,
Using the positioning member 100, the second output terminal area 23
Since the 5A can be positioned, the joining of the branch wiring portion 235 can be easily performed with high accuracy.

In this embodiment, the second wiring junction region 2
By joining the second output side terminal area 235A of the flexible wiring board 23 and the bonding wiring portion 33 on the short side of 6A, the bonding margin and the folding margin of the flexible wiring substrate at least on one side of the liquid crystal panel 21 can be reduced. Since it becomes unnecessary, the area ratio of the display area to the entire liquid crystal panel 21 can be increased. By thus increasing the area ratio of the display region, display visibility can be improved.

Further, according to the present embodiment, the flexible wiring board 23 is connected to the liquid crystal panel 21 in one direction (Y in FIG. 1).
Direction), the terminal connection step can be facilitated. Further, according to the present embodiment, using one flexible wiring substrate 23, first wiring bonding region 25A and second wiring bonding region 26A formed on first and second substrates 25 and 26, respectively. Can be connected, so that the convenience of the flexible wiring board 23 can be improved.

Further, since the input wiring portion 236 of the flexible wiring board 23 can be joined to the printed board 24 at one place, the joining process between the flexible wiring board 23 and the printed board 24 can be simplified. it can. Also, the flexible wiring board 23 and the printed circuit board 2
4 can be joined at one place, so that the printed circuit board 24
Can be reduced in size.

(Modification of Branch Wiring Unit) FIGS. 7 and 8
Next, another modified example of the branch wiring portion 235 of the flexible wiring board 23 is shown. FIG. 8 is a sectional view taken along line BB in FIG. 7 and 8, portions having substantially the same functions as those in FIGS. 3 and 4 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this example, two single-sided substrates are used. That is, the flexible wiring board 23 has a structure in which the board main body 234 and the branch wiring portion 235 are formed separately, and both are joined by the anisotropic conductive film.
As shown in FIG. 8, the substrate main body 234 includes a first flexible substrate (first base sheet) 231A and a conductive layer made of, for example, a copper foil formed on the lower surface of the flexible substrate 231A. The conductive layer includes a signal wiring 232 and an upper scanning wiring 233A. Further, the branch wiring portion 235 includes a second flexible substrate (second base sheet) 231B and a lower scanning wiring 233 formed on the flexible substrate 321B.
B, the lower scanning wiring 233B and the upper scanning wiring 2
Bump-shaped contact layer 233C connecting to 33A
And a solder resist layer 239A. Then, the scanning wiring 233 is configured by the upper scanning wiring 233A, the contact layer 233C, and the lower scanning wiring 233B. Further, the substrate main body 234 and the branch wiring portion 235 are joined by an anisotropic conductive film 239B.

The flexible wiring board is not limited to the above example, but may have various wiring structures and layer structures.

(Modification of Liquid Crystal Panel) FIG. 9 shows a modification of the liquid crystal panel 21. 9, parts having substantially the same functions as those in FIG. 1 are denoted by the same reference numerals, and a detailed description thereof will be omitted.

In the liquid crystal panel shown in FIG. 1, an example is shown in which the flexible wiring board of the present invention is applied to a liquid crystal panel of a passive matrix drive system. However, the flexible wiring board of the present invention has a TFD as a switching element of a pixel electrode.
The present invention can also be applied to an active matrix driving type liquid crystal panel using a (Thin Film Diode) element.

Since the structure of the first bonding region 25A and the second bonding region 26A is the same as that of the liquid crystal panel of FIG. 1, the structure inside the sealing material is shown in FIG.

The liquid crystal panel 21 has a first substrate 25 and a second substrate 26 arranged to face each other. Between these first and second substrates 25 and 26,
A sealing material (not shown) is arranged so as to go around the display area. Then, these first and second substrates 25, 2
A liquid crystal layer (not shown) is sealed in a region formed by 6 and the sealing material. First and second substrates 25, 26
Is composed of, for example, a glass substrate, a plastic substrate, or the like.

The second substrate 25 is provided on the surface of the first substrate 25.
A plurality of pixel electrodes 1034 arranged in a matrix and a signal electrode 27 extending in the X direction are arranged on the surface of the TF is applied to one signal electrode 27, respectively.
They are commonly connected via a D element 1020. The pixel electrode 1034 is formed using a conductive material having transparency with respect to display light,
For example, it is formed of ITO (Indium Tim Oxide). The TFD element 1020 includes a first metal film 1022, an oxide film 1024 obtained by anodizing the first metal film 1022, and a second metal film 1026 when viewed from the substrate 25 side. Adopt a body / metal sandwich structure. For this reason, the TFD element 1020 has positive and negative bidirectional diode switching characteristics.

On the other hand, on the surface of the second substrate 26, the first
A plurality of scan electrodes 28 are provided on the surface of the
Is arranged. These scanning electrodes 28 are arranged in parallel in a predetermined direction (the Y direction in FIG. 9) orthogonal to the signal electrodes 27 with a predetermined interval therebetween, and serve as electrodes facing the pixel electrodes 1034. They are arranged. Although not shown in FIG. 9, the color filters are provided corresponding to the regions where the scanning electrodes 28 and the pixel electrodes 1034 cross each other.

The liquid crystal panel 21 is shown in FIGS.
1 has a first wiring junction region 25A and a second wiring junction region 26A on two adjacent sides as in the embodiment shown in FIG. 1 and is similar to the embodiment shown in FIGS. The flexible wiring board shown in FIGS. 3 and 4 or the flexible wiring board shown in FIGS.

Although the embodiments of the present invention have been described above, the method for connecting a flexible wiring board according to the present invention,
The method of manufacturing the electro-optical device is not limited to the above-described configuration, and various changes can be made within the scope of the present invention.

For example, in terms of the driving method, a liquid crystal panel is a simple matrix liquid crystal panel or a static driving liquid crystal panel using no switching element in the panel itself, or a three-terminal switching element represented by a TFT or a TFD represented by a TFD. An active matrix liquid crystal panel using a terminal switching element, and various types of liquid crystal panels such as TN type, STN type, guest host type, phase transition type, and ferroelectric type can be used in terms of electro-optical characteristics.

In the above-described embodiment, an example is shown in which the flexible wiring board is used for connecting the liquid crystal panel and the circuit board. However, in the case of connecting another type of display panel, for example, a display plasma panel to the circuit board. Needless to say, it can also be used. Further, in the above-described embodiment, the signal electrode 27 is formed of a material having transparency with respect to display light, and the first substrate 25 on which the signal electrode 27 is formed is set as the front substrate. May be formed.

In the above-described embodiment, the signal wiring 232 formed on the flexible wiring board 23 is used.
The wiring of the scanning wiring 233 can be changed as appropriate according to the arrangement of the joints of the liquid crystal panel 21.

Further, in the above-described embodiment,
Wiring joint area 25 of first and second substrates 25 and 26
A, 26A with signal driver ICs 29, 30, 32, C
Although the OG is mounted, the driver IC does not have to be formed on the substrate. For example, a terminal portion of a signal electrode or a scanning electrode is arranged in a wiring joint region, and a driver I is provided between these terminal portions and a terminal region of a flexible printed wiring board.
A configuration may be adopted in which a tape carrier package on which C is mounted is interposed.

In the above-described embodiment, the liquid crystal display device is constituted by the liquid crystal panel and the circuit board on which the drive circuit and the like are mounted. However, the drive circuit and the like are also provided on the transparent substrate constituting the liquid crystal panel. When mounted, other circuits are formed on the circuit board and the flexible wiring board.

Further, in the above-described embodiment, a case where an LCD display is used as an electro-optical display panel has been described. However, the present invention is not limited to this. For example, a small-sized cathode ray tube or a small-sized Television, electroluminescence, plasma display, CRT display, FED (FieldEmi
Various electro-optical means such as a ssion display panel can be used.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a liquid crystal display device to which an electro-optical device manufacturing method according to the present invention is applied.

FIG. 2 is an enlarged plan view showing a part of the liquid crystal display device shown in FIG.

FIG. 3 is a plan view schematically showing a flexible wiring board used in the method for connecting a flexible wiring board according to the present invention.

FIG. 4 is a cross-sectional view schematically showing a portion along the line AA in FIG. 3;

FIG. 5 is a view showing a method for connecting a flexible wiring board according to the present invention.

FIG. 6 is a plan view schematically showing a part of a crimping device used in the method for connecting a flexible wiring board according to the present invention.

FIG. 7 is a plan view schematically showing another example of a flexible wiring board used in the method for connecting a flexible wiring board according to the present invention.

FIG. 8 is a cross-sectional view schematically showing a portion along line BB of FIG. 7;

FIG. 9 is a partially broken perspective view schematically showing a part of a modification of the liquid crystal panel used in the method of manufacturing an electro-optical device according to the present invention.

FIG. 10 is a plan view schematically showing an example of a conventional liquid crystal display device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 liquid crystal display device 21 liquid crystal panel 23 flexible wiring board 24 printed circuit board 25, 26 substrate 25A, 26A wiring bonding area 27 signal electrode 28 scanning electrode 29, 30 signal driver IC 31 bonding terminal 32 scanning driver IC 33 bonding terminal 231 Flexible substrate 232 Signal wiring 233 Scanning wiring 234 Substrate body 235 Branch wiring parts 234A, 235A Output terminal area 236A Input terminal area 100 Positioning member 110, 120 Side plate 130 Heat bonding part 150 Pressure bonding apparatus 1020 TFD element 1022 First Metal film 1024 Anodized film 1026 Second metal film 1034 Pixel electrode

Continued on the front page F term (reference) 2H092 GA40 GA49 GA50 GA60 JA01 NA25 NA27 QA07 QA08 QA10 QA11 QA13 5C094 AA14 AA15 AA43 AA47 AA48 BA29 BA43 CA19 DA09 DA12 DB02 EA10 FB12 FB15 GB01 5E344 AA02 BB15 DD22 BB15 DD04 AA17 AA18 BB05 BB12 CC09 EE32 EE37 EE47 HH12 HH14 KK02 KK03

Claims (18)

[Claims] 1. A method for connecting a flexible wiring board to a body to be joined, comprising the following steps (a) to (e):
Flexible wiring board connection method. (A) a step of detecting a region to which a terminal portion of the flexible wiring board is bonded in a wiring bonding region of the body to be bonded; (b) a step of bonding the terminal portion detected in the step (a). Arranging a positioning member for determining the position of the terminal portion in the area; (c) arranging the terminal portion at a predetermined position by the locating member; and (d) positioning the terminal portion in the step (c). Temporarily fixing the terminal portion; and (e) joining the terminal portion to the wiring joining region after removing the positioning member. 2. The method for connecting a flexible wiring board according to claim 1, wherein the positioning member is provided in a device for temporarily fixing the terminal portion in the step (d). 3. The method according to claim 2, wherein the positioning member is movably provided. 4. The method according to claim 1, wherein the positioning member comprises a substantially U-shaped frame member having one end opened. 5. A method of manufacturing an electro-optical device, comprising a step of connecting a flexible wiring board to an electro-optical panel, wherein the electro-optical device comprises a first substrate and a second substrate which face each other.
The first substrate has a first wiring bonding region that does not overlap with the second substrate, and the second substrate has the first substrate. A flexible wiring board, wherein the flexible wiring board is provided with a board body, a branch wiring portion provided by branching from the board body, and a first wiring board provided on the board body. An output side terminal area, a second output side terminal area provided in the branch wiring section, and an input side terminal area, and including the following steps (A) and (B); The first output terminal area of the flexible wiring board is connected to the first wiring bonding area; and (B) the second output terminal area of the flexible wiring board is connected to the second wiring. Connected to the bonding region, and the step (B) is The following steps (a) ~ (e)
A method for manufacturing an electro-optical device including: (A) detecting, in the second wiring bonding region, a region to which the second output-side terminal region of the flexible wiring board is bonded; (b) detecting the region detected in the step (a); Disposing a positioning member for determining the position of the second output-side terminal region in a region where the second output-side terminal region is joined; and (c) disposing the second output-side terminal region by the positioning member. (D) temporarily fixing the second output-side terminal area positioned in the step (c), and (e) removing the positioning member and then outputting the second output. Bonding a side terminal region to the second wiring bonding region. 6. The method according to claim 5, wherein the positioning member is provided in the step (d).
The method for manufacturing an electro-optical device provided in a device for temporarily fixing the output-side terminal region of (1). 7. The method according to claim 6, wherein the positioning member is movably provided. 8. The method of manufacturing an electro-optical device according to claim 5, wherein the positioning member comprises a substantially U-shaped frame member having one end opened. 9. The flexible wiring board according to claim 5, wherein the flexible wiring board has a wiring arrangement direction in the first output terminal area and a wiring arrangement direction in the second output terminal area. Are the same, a method of manufacturing an electro-optical device. 10. The flexible wiring board according to claim 5, wherein the first output terminal area is provided on one surface of the substrate body, and wherein the second output terminal area is provided. Is provided on a surface opposite to a surface on which the first output-side terminal region is provided. 11. The method of manufacturing an electro-optical device according to claim 5, wherein the branch wiring portion of the flexible wiring board extends from the substrate body in a substantially L-shaped manner. 12. The method of manufacturing an electro-optical device according to claim 5, wherein an end of the branch wiring portion of the flexible wiring board is located before an end of the substrate main body. 13. The method of manufacturing an electro-optical device according to claim 5, wherein the electro-optical panel is a liquid crystal panel. 14. The wiring according to claim 5, wherein a signal wiring is provided in the first output terminal area, and a scanning wiring is provided in the second output terminal area. , An electro-optical device manufacturing method. 15. The method of manufacturing an electro-optical device according to claim 5, wherein a semiconductor device is mounted on at least one of the first wiring junction region and the second wiring junction region. 16. The method according to claim 15, wherein the semiconductor device is a driver IC. 17. The flexible wiring board according to claim 5, wherein the first output-side terminal area of the flexible wiring board is connected to the first wiring bonding area. 2. The method of manufacturing an electro-optical device, wherein the second output terminal region is joined to the second wiring joining region. 18. The method according to claim 5, wherein the step (a) further includes a step of detecting a wiring pattern formed in the second output terminal region of the flexible wiring board. A method for manufacturing an electro-optical device.