JP2007189046A - Method and device for connecting wiring board, mounting structure and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide connection method/device of a wiring board with which the size change is suppressed, there is less misplacements, and connection is realized with high accuracy, and to provide a mounting structure and an electronic apparatus. <P>SOLUTION: The method comprises a tension-adding process for grasping FPC41 and adding tension, in a direction of following the direction crossing an arranging direction of a first terminal electrode 55 with respect to FPC41, an abutting process for making a first terminal 53 abut against a second terminal 67, and a heating pressurizing process for pressurizing the first terminal 53, while it is heated directed toward the second terminal 67 and electrically connecting FPC 41 and a liquid crystal panel 42. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wiring board connecting method and a wiring board connecting apparatus for electrically connecting, for example, a flexible wiring board and an electronic component.

In recent years, electronic devices have been reduced in size and weight, and there is an increasing demand for downsizing and cost reduction of components used in electronic devices. In general, such a small component and an external substrate are connected using, for example, a flexible wiring substrate (hereinafter referred to as FPC) made of polyimide or the like. A terminal electrode that can be overlapped with a terminal electrode provided on a small component is provided on one end side of the FPC, and a wide and wide space that can be connected to an external substrate is provided on the other end side. A terminal electrode formed as described above is provided. The FPC includes wiring formed so as to connect the terminal electrode on one end side and the terminal electrode on the other end side, and the width and interval of the wiring are changed during the routing of the wiring.
For such connection between the FPC and the connected object, a conductive adhesive such as an anisotropic conductive film containing conductive particles is applied between the terminal electrode of the connected object and the terminal electrode of the FPC. These are performed by heating and pressing them using a bonding tool.

However, as the wiring density is increased, the arrangement interval of the terminal electrodes is narrowed, and the FPC is changed in dimensions when heated and pressurized, so that the terminal electrodes of the FPC and the terminal electrode of the connected object are connected. Misalignment may occur at the time of connection.
A method of connecting each wiring pattern using a flexible wiring board that has been corrected in advance in anticipation of the dimensional change of the flexible wiring board in order to suppress the positional deviation due to the dimensional change that occurs during connection in this way. (For example, refer patent document 1) and the method (for example refer patent document 2) which connect each wiring pattern after temporarily fixing a flexible wiring board are proposed.
JP-A-4-28289 Japanese Patent Laid-Open No. 1-189988

  However, the conventional wiring board connection method has the following problems. That is, the dimensional change amount at the time of connecting the flexible wiring board is different for each flexible wiring board depending on the connection conditions, temperature, humidity, and the like, so it is difficult to suppress the dimensional change at the time of connection. Also in such a wiring board connection method, it is desired that the pitch of the terminal electrodes of the flexible wiring board be made narrower in order to increase the wiring density. For this reason, it is necessary to connect each terminal electrode with higher accuracy.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems. A wiring board connection method, a wiring board connection device, and a mounting structure that can suppress a dimensional change, have less positional deviation, and can be connected with high accuracy. It aims at providing a body and an electronic device.

  The present invention employs the following configuration in order to solve the above problems. In other words, the wiring board connection method according to the present invention is provided on the object to be connected and the first terminal portion composed of a plurality of linear first terminal electrodes provided at intervals on the flexible wiring board. In the method of connecting a wiring board for connecting to the second terminal portion, the flexible wiring board is gripped and along a direction intersecting the arrangement direction of the first terminal electrodes with respect to the flexible wiring board. A tension applying step of applying a tension in the direction of contact, a contact step of bringing the first terminal portion and the second terminal portion into contact, and heating the first terminal portion toward the second terminal portion. It is characterized by comprising a heating and pressing step of applying pressure to electrically connect the flexible wiring board and the object to be connected.

In this invention, when the flexible wiring board is heated and pressed to connect the first terminal portion and the second terminal portion, tension is applied to the flexible wiring substrate in a direction crossing the arrangement direction of the first terminal electrodes. Since it is added, the dimensional deviation in the pitch direction, which is the arrangement direction of the first terminal electrodes, is reduced. For this reason, the connection between the first terminal portion and the second terminal portion can be performed with high accuracy.
That is, by applying tension to the flexible wiring board, the dimensional change amount of the flexible wiring board during heating is large in the extending direction of the first terminal electrode, which is the direction in which the tension is applied, and the tension is applied. It becomes smaller in the pitch direction of the first terminal electrode, which is a non-existing direction.
Therefore, the pitch of the first terminal electrodes can be reduced, and the connection between the first terminal portion and the second terminal portion where the first terminal electrodes are arranged at a higher density can be performed with high accuracy.

In the wiring board connection method according to the present invention, it is preferable that the contact step is performed after the tension applying step.
According to the present invention, the first terminal portion is brought into contact with the second terminal portion while tension is applied to the flexible wiring board, compared with the case where tension is applied while both terminal portions are brought into contact with each other. Thus, the connection between the first terminal portion and the second terminal portion can be performed with higher accuracy.

In the wiring board connection method according to the present invention, it is preferable that the tension applied to the flexible wiring board is adjusted in the tension applying step according to a dimensional change due to heating of the flexible wiring board.
In this invention, the positional shift in the pitch direction of the first terminal portion can be further suppressed by adjusting the tension applied to the flexible wiring board in accordance with the dimensional change amount.

Moreover, it is preferable that the connection method of the wiring board concerning this invention is equipped with the cancellation | release process which cancels | releases the tension | tensile_strength added to the said flexible wiring board after the said heating-pressing process.
In this invention, it can suppress that a 1st terminal part and a 2nd terminal part disconnect, when tensile stress concentrates in the connection boundary part of a 1st terminal part and a 2nd terminal part.

In the wiring board connection method according to the present invention, it is preferable that a conductive adhesive is interposed between the first terminal portion and the second terminal portion.
In this invention, the electrical connection between the first terminal portion and the second terminal portion can be further strengthened by interposing a conductive adhesive.

In addition, the wiring board connecting device according to the present invention is provided in a first terminal portion constituted by a plurality of linear first terminal electrodes provided at intervals on a flexible wiring board, and on an object to be connected. In the wiring board connecting apparatus for connecting the second terminal portion, tension applying means for holding the flexible wiring board and applying tension in a direction along the direction intersecting the arrangement direction of the first terminal electrodes; And heating and pressurizing means for pressing the first terminal portion while heating it toward the second terminal portion in a state where tension is applied to the flexible wiring board.
In the present invention, by applying tension to the flexible wiring board, the dimensional deviation is reduced in the pitch direction of the first terminal electrode, which is the direction in which no tension is applied, as described above. The pitch can be reduced. Therefore, the connection between the first terminal portion and the second terminal portion in which the first terminal electrodes are arranged with higher density can be performed with high accuracy.

In the wiring board connecting apparatus according to the present invention, the tension applying unit may move the gripped flexible wiring board in a direction along a direction intersecting the arrangement direction of the first terminal electrodes. .
In this invention, tension is applied to the flexible wiring board by moving the flexible board held by the tension applying means in a direction intersecting the arrangement direction of the first terminal electrodes.

In the wiring board connecting apparatus according to the present invention, it is preferable that the tension applying unit includes a tension adjusting unit that adjusts a tension applied to the flexible substrate according to the flexible wiring substrate.
In this invention, it can avoid that a 1st terminal part disconnects by adjusting the tension | tensile_strength added according to a flexible wiring board.

The wiring board connecting device according to the present invention further comprises a tension addition release control means for releasing the tension applied to the flexible wiring board after the first terminal portion is connected to the second terminal portion. It is good.
In this invention, it can suppress that a 1st terminal part and a 2nd terminal part disconnect, when tensile stress concentrates in the connection boundary part of a 1st terminal part and a 2nd terminal part.

A mounting structure according to the present invention is manufactured using the wiring board connection method described above.
In the present invention, by using the above-described wiring board connection method, the pitch of the first terminal electrodes can be reduced, and the first terminal portion and the second terminal in which the first terminal electrodes are arranged at a higher density. The connection with the part can be performed with high accuracy.

In addition, an electronic device according to the present invention includes the mounting structure described above.
In this invention, by providing the mounting structure described above, the pitch of the first terminal electrodes can be reduced, and the first terminal portions and the second terminal portions in which the first terminal electrodes are arranged at a higher density, Can be connected with high accuracy.

A wiring board connecting method, a wiring board connecting device, a mounting structure, and an electronic device according to a first embodiment of the present invention will be described below with reference to the drawings.
The wiring board connecting device in the present embodiment forms a mounting structure by electrically connecting a flexible wiring board (hereinafter referred to as FPC) and an object to be connected. Then, as shown in FIG. 1, the wiring board connecting device 1 heats the FPC 41, a mounting table 2 on which a liquid crystal panel (an object to be connected) 42 described later is mounted, a fixing unit 3 that fixes an FPC 41 described later. The heating / pressurizing unit 4 for applying pressure and the tension applying unit 5 for applying tension to the FPC 41 are provided.

The mounting table 2 has a recess formed in a part of its upper surface 2a, and a guide plate 11 is fitted in the recess.
The guide plate 11 is provided to hold the liquid crystal panel 42, and is made of a material according to the material and thermal conductivity of the liquid crystal panel 42 to be held and the surface roughness of the contact surface of the liquid crystal panel 42 with the guide plate 11. Different ones are provided. Here, the upper surface of the guide plate 11 may be a mirror surface, but in order to prevent heat applied from the heating and pressurizing unit 4 to the liquid crystal panel 42 from being radiated to the mounting table 2 through the guide plate 11. It is preferable that the surface roughness of the back surface of the liquid crystal panel 42 to be placed is smoother, that is, the surface roughness of the back surface of the liquid crystal panel 42 is rougher than the surface roughness of the upper surface of the guide plate 11.

The guide plate 11 is made of, for example, metal, ceramics, glass, or the like. However, when the FPC 41 and the liquid crystal panel 42 are connected, the guide plate 11 is pressed by a head unit 15 (to be described later) of the heating and pressurizing unit 4, so that the guide plate 11 has a hardness having resistance to a pressure higher than the pressurizing pressure. It is necessary that the material has a heat resistance equal to or higher than the connection temperature. Furthermore, it is more preferable if the material has a low thermal conductivity.
Further, in order to suck and hold the liquid crystal panel 42 placed on the guide plate 11, a suction port (not shown) is formed on the mounting table 2 so as to surround the guide plate 11. This suction port is connected to a vacuum pump. Note that this suction port may be formed in the recess of the mounting table 2. In this case, it is necessary to form a through hole at a position where the guide plate 11 contacts the suction port.

  The fixing portion 3 is disposed along the longitudinal direction of the FPC 41 which is the same as the extending direction of the first terminal electrode 55 described later formed on the FPC 41 by sandwiching the FPC 41 together with the grip portion 22 described later of the tension applying portion 5. It is configured to add tension. Further, the holding position of the FPC 41 by the fixing portion 3 is a position through the connection area of the FPC 41 with the liquid crystal panel 42 with respect to the holding position of the FPC 41 by the grip portion 22.

The heating and pressing unit 4 includes a head unit 15, a support shaft 16 that moves up and down in the vertical direction together with the head unit 15, and a protruding portion 17 provided on the support shaft 16.
The head unit 15 is a constant heat type head in which a heating mechanism such as a heater is provided, and can be set to an arbitrary temperature in a temperature range of about 200 ° C to 450 ° C. Further, the bottom surface of the head portion 15 is a flat surface. The head unit 15 is attached to a support member (not shown) via a support shaft 16. In addition, it is preferable that the bottom surface of the head unit 15 has a configuration in which a jig can be attached in accordance with the shapes of the FPC 41 and the liquid crystal panel 42 to be connected. In this way, the contact surface can be set to a square, a long and narrow rectangle, or any other shape.

The support shaft 16 is movable up and down in the vertical direction by a vertical drive mechanism (not shown) such as a cylinder.
The protruding portion 17 is formed to protrude in a horizontal direction perpendicular to the vertical direction that is the moving direction of the support shaft 16, and moves up and down together with the support shaft 16 when the support shaft 16 moves up and down in the vertical direction. It is possible. Further, when the support shaft 16 moves downward in the vertical direction, the protruding portion 17 comes into contact with a later-described contact portion 25 of the tension applying portion 5 and further moves the support shaft 16 downward in the vertical direction. The abutting portion 25 is pushed downward in the vertical direction. Here, the timing at which the protruding portion 17 contacts the contact portion 25 is before the bottom surface of the head portion 15 contacts the FPC 41.

The tension applying unit 5 includes an arm unit 21, a gripping unit 22 that grips the FPC 41, and a tension adjusting unit (tension adjusting unit) 23 that connects the arm unit 21 and the gripping unit 22.
The arm portion 21 is formed to be bent in an L shape, and a turning shaft 24 that can turn around the axis parallel to the pitch direction that is the arrangement direction of the first terminal electrodes 55 of the FPC 41 at the bent portion. Is provided. An abutting portion 25 is provided on one end side of the arm portion 21 so as to abut on the protruding portion 17 when the support shaft 16 moves downward. For this reason, the arm portion 21 is configured so that the projecting portion 17 contacts the contact portion 25 when the support shaft 16 moves downward, and further the support portion 16 moves downward so that the arm 21 has the pivot shaft 24 as a fulcrum. The part 21 and the grip part 22 are configured to rotate in the direction of the arrow A1 shown in FIG.
Moreover, the thin part 21a is formed in the other end of the arm part 21, The through-hole (not shown) penetrated in the thickness direction is formed in this thin part 21a.

  The grip portion 22 is configured to grip the FPC 41 by clamping, and a thin portion 22 a is formed at one end close to the arm portion 21. And the holding part 22 is the structure which pulls FPC41 hold | gripped by the arm part 21 turning in the A1 direction shown in FIG. 1 around the axis | shaft of the rotating shaft 24, and adds tension | tensile_strength with respect to FPC41. It has become.

The tension adjusting unit 23 includes a screw part 26 screwed to the thin part 22 a and a spring part 27 attached to the screw part 26.
The shaft of the screw portion 26 is inserted into the through hole of the thin portion 21a, and a support portion 26a having a larger diameter than the shaft portion is provided at one end thereof.
The spring portion 27 is constituted by, for example, a coil spring, and the shaft portion is inserted therethrough, one end is in contact with the thin portion 21a and the other end is in contact with the support portion 26a.
Therefore, the tension adjusting unit 23 is configured such that the spring portion 27 is compressed by the thin portion 21a when the arm portion 21 rotates in the direction of the arrow A1 shown in FIG. When the spring portion 27 is compressed and presses the support portion 26a, the thin portion 22a rotates in the direction of the arrow A1 around the rotation shaft 24 via the support portion 26a and the screw portion 26. Therefore, the tension adjusting unit 23 can adjust the tension applied to the FPC 41 by adjusting the spring constant of the spring portion 27 to rotate the arm portion 21 around the rotating shaft 24.

  Further, the wiring board connecting apparatus 1 includes tension addition release control means (not shown) for releasing the tension applied to the FPC 41 after connecting the first terminal portion 53 to the second terminal portion 67.

Next, the mounting structure manufactured by the wiring board connecting apparatus 1 described above will be described.
As shown in FIG. 2, the mounting structure 40 has a configuration in which an FPC 41 and a liquid crystal panel 42 are electrically connected.

  The FPC 41 is formed on the base substrate 51, the wiring pattern 52 formed on the base substrate 51, and the wiring pattern 52, and is connected to a later-described second terminal portion 67 of the liquid crystal panel 42. A first terminal portion 53 and a semiconductor chip 54 mounted at a predetermined position on the base substrate 51 are provided.

The base substrate 51 is made of an insulating film made of polyimide, for example.
Further, the wiring pattern 52 and the first terminal portion 53 are formed by patterning a metal film such as copper (Cu) formed on the base substrate 51. The first terminal portion 53 includes a plurality of linear first terminal electrodes 55 formed at intervals, and each of the first terminal portions 53 is electrically connected to the semiconductor chip 54. The first terminal electrode 55 is formed in the same direction as the longitudinal direction of the FPC 41.
The FPC 41 may have a configuration in which a resistor, a capacitor, and other chip components are mounted on the base substrate 51 in addition to the semiconductor chip 54. Further, the semiconductor chip 54 may not be mounted.
Here, the base substrate 51 has a thickness of, for example, 25 μm, the wiring pattern 52 and the first terminal portion 53 have a thickness of, for example, 8 μm, and the first terminal electrode 55 has a pitch of, for example, 38 μm and the number of terminals of about 400 terminals. It has become.
The FPC 41 is fixed to a TFT array substrate 61 (described later) of the liquid crystal panel 42 through an anisotropic conductive film (ACF: Anisotropic Conductive Film) 56.

As shown in FIG. 2, the liquid crystal panel 42 includes a TFT array substrate 61, a counter substrate 62 arranged to face the TFT array substrate 61, a sealing material 63 for bonding the TFT array substrate 61 and the counter substrate 62, and a TFT array. And a liquid crystal (not shown) sealed in a cell gap which is a gap formed by the substrate 61 and the counter substrate 62. That is, the liquid crystal is sandwiched between the TFT array substrate 61 and the counter substrate 62.
The liquid crystal panel 42 includes a polarizing plate 64 attached to the outer surface of the TFT array substrate 61 and a polarizing plate (not shown) attached to the outer surface of the counter substrate 62.

The TFT array substrate 61 and the counter substrate 62 are made of a translucent material such as glass or synthetic resin. Here, when the TFT array substrate 61 and the counter substrate 62 are made of glass, borosilicate glass, quartz glass, and soda glass are desirable.
An electrode 65 is formed on the inner surface of the TFT array substrate 61, and an electrode 66 is formed on the inner surface of the counter substrate 62. These electrodes 65 and 66 are made of a light-transmitting conductive material such as ITO (Indium Tin Oxide), and are formed on stripes, letters, numbers, or other appropriate patterns. .

The TFT array substrate 61 has an overhanging portion 61a that protrudes from the counter substrate 62 when bonded to the counter substrate 62 via the sealing material 63, and the second terminal portion 67 is provided on the overhanging portion 61a. Is formed. The second terminal portion 67 is composed of a plurality of second terminal electrodes 68 arranged at intervals.
The plurality of second terminal electrodes 68 are formed at the same time as the electrodes 65 when the electrodes 65 are formed on the TFT array substrate 61, and are made of, for example, ITO like the electrodes 65. The second terminal electrode 68 includes one that extends integrally from the electrode 65 to the electrode 65 and one that is connected to the electrode 66 through a conductive material (not shown).
Here, a large number of actual electrodes 65 and 66 are formed on the TFT array substrate 61 and the counter substrate 62 with extremely narrow intervals, but in FIG. 2, in order to facilitate understanding of the structure of the liquid crystal panel 42, the electrodes While the formation intervals of 65 and 66 are schematically shown in an enlarged manner, only a few of them are shown, and the other parts are omitted. Further, the connection state between the second terminal electrode 68 and the electrode 65 and the connection state between the second terminal electrode 68 and the electrode 66 are also omitted in FIG.

Next, a method for manufacturing the mounting structure 40 will be described. In the following description, a method for manufacturing the FPC 41 and the liquid crystal panel 42 is omitted, and a method for connecting the FPC 41 and the liquid crystal panel 42 will be described.
First, as shown in FIG. 1, the liquid crystal panel 42 is placed on the mounting table 2, and the portion of the protruding portion 61 a where the second terminal portion 67 is formed in the liquid crystal panel 42 is positioned above the guide plate 11. Place. At this time, the liquid crystal panel 42 is sucked and fixed to the mounting table 2 by the suction port.

  Next, the anisotropic conductive film 56 is attached to the portion of the liquid crystal panel 42 where the second terminal portion 67 is formed. Here, the anisotropic conductive film 56 is attached so as to cover the entire second terminal portion 67 formed on the liquid crystal panel 42. On the other hand, the FPC 41 is sandwiched between the gripping portion 22 and the fixing portion 3 so that the first terminal portion 53 of the FPC 41 is positioned in a plan view between the gripping positions between the gripping portion 22 and the fixing portion 3. At this time, the grip portion 22 and the fixing portion 3 are arranged along the longitudinal direction of the FPC 41 so that the direction of the tension applied to the FPC 41 is the direction along the formation direction of the first terminal electrode 55 of the first terminal portion 53. It is clamped at a place (FIG. 1). Moreover, the temperature of the head part 15 is adjusted to a temperature in the range of about 210 ° C. to 450 ° C. so that the temperature of the anisotropic conductive film 56 becomes 200 ° C., for example. Note that the temperature of the head unit 15 may be appropriately adjusted according to the heating temperature of the anisotropic conductive film 56.

  Subsequently, a tension applying step is performed. This is because the second terminal portion 67 of the liquid crystal panel 42 to which the anisotropic conductive film 56 is attached and the first terminal portion 53 of the FPC 41 are aligned, and the support shaft 16 is moved downward by extending the cylinder. Move to. As described above, when the support shaft 16 is moved downward, the projecting portion 17 comes into contact with the contact portion 25 of the arm portion 21 and pushes the contact portion 25 downward. And the arm part 21 rotates in the arrow A1 direction shown in FIG. 3 around the axis | shaft of the rotating shaft 24 (FIG. 3).

Thus, when the arm part 21 rotates, the thin part 21a compresses the spring part 27, and the spring part 27 presses the support part 26a. Then, the thin portion 22 a of the grip portion 22 moves in the direction of the arrow A <b> 1 around the rotation shaft 24 via the screw portion 26. As described above, the grip portion 22 rotates in the direction of the arrow A1 around the rotation axis 24, whereby the tension along the extending direction of the first terminal electrode 55, which is the longitudinal direction of the FPC 41, is applied to the FPC 41. Added. Here, the tension applied to the FPC 41 is, for example, about 6N.
That is, in the tension applying step, the arm portion 21 is rotated around the rotation shaft 24, and the grip portion 22 is moved around the rotation shaft 24 via the spring portion 27. It is added. Here, by adjusting the spring constant of the spring portion 27, the force around the rotation shaft 24 transmitted from the arm portion 21 to the grip portion 22 can be adjusted.

  Furthermore, when the support shaft 16 is moved downward while applying tension to the FPC 41 in this way, the head portion 15 approaches the FPC 41 and the base substrate 51 of the FPC 41 is thermally deformed by the radiant heat from the head portion 15. However, since the tension along the longitudinal direction is preliminarily applied to the FPC 41, the thermal change in the first terminal portion 53 has a change amount in the width direction smaller than a change amount in the longitudinal direction. Thereby, the dimensional change in the pitch direction of the some 1st terminal electrode 55 can be suppressed.

Next, a contact process is performed. This further moves the support shaft 16 downward to bring the head portion 15 into contact with the FPC 41, thereby bringing the first terminal portion 53 and the second terminal portion 67 into contact.
Subsequently, a heating and pressing step is performed. In this state, the first terminal portion 53 is pressed toward the second terminal portion 67 by moving the support shaft 16 further downward with the head portion 15 in contact with the FPC 41 (FIG. 4). At this time, the anisotropic conductive film 56 is softened and melted by the heat supplied from the head unit 15, and is pressed between the first terminal unit 53 and the second terminal unit 67 by being pressed by the head unit 15. In addition, the conductive particles in the anisotropic conductive film 56 are deformed and sandwiched. Thereby, the 1st terminal part 53 and the 2nd terminal part 67 are connected. Here, the heating and pressurizing time of the head unit 15 is about 3 to 15 seconds, and the pressurizing pressure is about 30 kg / cm ² . Further, even if the base substrate 51 is thermally deformed by heating by the head portion 15, since the tension is applied in the longitudinal direction of the FPC 41, the deformation direction is limited as described above. At this time, the dimensional change rate in the width direction of the FPC 41 is, for example, 0.15% when no tension is applied, and is 0.02%, for example, when the tension is applied. Thus, the dimensional change in the arrangement direction of the first terminal electrode 55 can be suppressed.

  Thereafter, a release process is performed. This releases the tension and clamping state applied to the FPC 41. First, the head portion 15 is separated from the FPC 41 by expanding and contracting the cylinder and moving the support shaft 16 upward. Further, by moving the support shaft 16 upward, the downward pressing state of the arm portion 21 against the contact portion 25 by the projecting portion 17 is gradually released, and the arm portion 21 is shown around the rotation shaft 24. 5 is rotated in the direction of arrow A2 shown in FIG. Then, the thin portion 21a of the arm portion 21 moves in the arrow A2 direction, whereby the spring portion 27 extends, and the thin portion 22a moves in the arrow A2 direction via the screw portion 26. As a result, one end of the FPC 41 sandwiched between the gripping portions 22 moves in the arrow A2 direction, and the tension applied to the FPC 41 is reduced.

When the support shaft 16 is further moved upward, the projecting portion 17 is separated from the contact portion 25 of the arm portion 21. As a result, the tension applied to the FPC 41 is released. Thereafter, the holding state of the FPC 41 by the grip portion 22 and the fixing portion 3 is released. Then, the support shaft 16 is further moved upward. Thereafter, the portion of the FPC 41 that has been gripped by the grip portion 22 is excised. Note that this portion may be left as it is without being excised.
As described above, the FPC 41 and the liquid crystal panel 42 are connected. In this way, the mounting structure 40 is manufactured.

The mounting structure 40 manufactured in this way is provided in a notebook personal computer (electronic device) 70 as shown in FIG. 6, for example.
The notebook personal computer 70 includes a casing 71, a liquid crystal display device 72 having a liquid crystal panel 42 constituting the mounting structure 40, a keyboard 73, a CPU (central processing unit) disposed in the casing 71, and the like. And an electronic component (not shown) such as a hard disk.

  As described above, according to the wiring board connecting method, the wiring board connecting apparatus 1, the mounting structure 40, and the notebook personal computer 70 according to the present embodiment, the FPC 41 is heated and pressed to form the first terminal portion 53 and the second terminal. Since the tension is applied to the FPC 41 so as to be in the same direction as the extending direction of the first terminal electrode 55 when the connection with the portion 67 is performed, a dimensional change in the pitch direction of the first terminal electrode 55 can be suppressed. . Thereby, the pitch of the 1st terminal electrode 55 can be made small, the 1st and 2nd terminal electrodes 55 and 68 can be densified, and a connection can be performed with high precision. The first terminal portion 53 and the second terminal portion 67 in which the first and second terminal electrodes 55 and 68 are arranged at a higher density can be connected with high accuracy.

Further, since the first terminal portion 53 is brought into contact with the second terminal portion 67 with tension applied to the FPC 41, the FPC 41 changes in size in the pitch direction of the first terminal electrode 55 due to the radiant heat of the head portion 15. Therefore, the first and second terminal electrodes 55 and 68 can be connected more accurately.
The tension adjusting unit 23 adjusts the tension applied according to the material of the FPC 41 and the dimensional change during heating, and the optimum tension is applied to the FPC 41. Therefore, the position of the first terminal electrode 55 in the pitch direction is adjusted. The shift can be suppressed and the first terminal electrode 55 can be prevented from being disconnected.

Moreover, tensile stress concentrates in the connection boundary part of the 1st and 2nd terminal parts 33 and 47 by canceling | releasing the addition of the tension | tensile_strength to FPC41 after the connection of the 1st terminal part 53 and the 2nd terminal part 67. It is possible to prevent the first terminal electrode 55 and the second terminal electrode 68 from being disconnected.
Further, by interposing the anisotropic conductive film 56 between the first terminal portion 53 and the second terminal portion 67, the electrical connection between the first and second terminal portions 33 and 47 can be further strengthened.

In this embodiment, a notebook personal computer is described as an electronic device. However, the present invention is not limited to this, and a liquid crystal projector, a multimedia-compatible personal computer (PC), an engineering workstation (EWS), a mobile phone, Application to pagers, word processors, television receivers, viewfinder type or monitor direct view type video tape recorders, electronic notebooks, electronic desk calculators, car navigation devices, POS (Point-Of-Sale) terminals, devices with touch panels, etc. Can do.
Further, the mounting structure 40 is not limited to the one including the liquid crystal panel 42 but may include one including an organic EL panel or one including an FED (Field Emission Display).

Next, a second embodiment of the mounting structure and the electronic device connected by the wiring board connecting device 1 described above will be described.
The mounting structure in the present embodiment is a droplet discharge head, and discharges ink (functional liquid) from a nozzle in the form of droplets.
As shown in FIG. 7, the droplet discharge head 100 includes an FPC (flexible wiring board) 101 connected to a later-described lead electrode group (second terminal portion) 135A and 135B, and a head body portion ( Connected object) 102.

  The FPC 101 includes a base substrate 105, a wiring pattern 106 formed on the base substrate 105, and terminal electrodes 107 that are formed on the base substrate 105 in the same manner as the wiring pattern 106 and are connected to lead electrodes 135 described later. And a drive circuit unit 108 mounted at a predetermined position on the base substrate 105. The FPC 101 is connected to the lead electrode groups 135A and 135B via an anisotropic conductive film (conductive adhesive) 109, respectively.

  The terminal electrodes 107 are provided in a vacant array in the Y-axis direction shown in FIG. 7, and the terminal electrode group (first terminal portion) is formed by the terminal electrode 107 connected to the lead electrode 135 constituting the lead electrode group 135A. A terminal electrode group (first terminal portion) 107B is configured by the terminal electrode 107 connected to the lead electrode 135 constituting the lead electrode group 135B.

  The drive circuit unit 108 is an IC driver having, for example, a circuit board and a semiconductor integrated circuit (IC) including a drive circuit, and is molded with a resin 110 provided on an upper surface of a stepped part on a reservoir forming substrate 115 described later. Has been. The drive circuit unit 108 is electrically connected to an external controller 159 described later connected to the outside of the droplet discharge head 100, and the droplet discharge head 100 is controlled by the external controller 159.

  The head main body 102 is displaced by driving the piezoelectric element 113, the nozzle substrate 111, the flow path forming substrate 112 provided on the upper surface (+ Z side) of the nozzle substrate 111, and the upper surface of the flow path forming substrate 112. A diaphragm 114 and a reservoir forming substrate 115 provided on the upper surface of the diaphragm 114 are provided.

  The nozzle substrate 111 is made of, for example, glass ceramics. A plurality of (for example, 720) nozzle openings 116 which are through holes penetrating the nozzle substrate 111 and discharge functional liquid droplets are arranged in the Y-axis direction. Is formed. A plurality of nozzle openings 116 formed side by side in the Y-axis direction constitute nozzle opening groups 116A and 116B. Here, the nozzle opening group 116A is located on the + X side with respect to the nozzle opening group 116B.

  The flow path forming substrate 112 is made of, for example, silicon, and a plurality of through holes and a plurality of partition walls 117 projecting inward from the side walls of the through holes are formed by anisotropic etching. The plurality of partition walls 117 are formed in a substantially comb-like shape in plan view, and define the through holes. Further, the nozzle substrate 111 is provided on the lower surface of the flow path forming substrate 112 so as to cover the lower surface side of the through hole. A vibration plate 114 is provided on the upper surface of the flow path forming substrate 112.

The through hole formed in the flow path forming substrate 112 is surrounded by the flow path forming substrate 112, the nozzle substrate 111, and the vibration plate 114, thereby forming a pressure generation chamber 118.
A plurality of the pressure generation chambers 118 are formed side by side in the Y-axis direction so as to correspond to the nozzle openings 116 constituting the nozzle opening groups 116A and 116B. A plurality of pressure generating chambers 118A formed corresponding to the nozzle opening group 116A constitutes a pressure generating chamber group 118A, and a plurality of pressure generating chambers 118 formed corresponding to the nozzle opening group 116B are used for pressure. A generation chamber group 118B is formed.
Further, the end portion of the pressure generating chamber 118 on the outer edge side of the substrate is communicated with each other by a communication portion 123 via a supply path 122 that constitutes a part of the reservoir 121. The communication portion 123 is a through hole formed in the flow path forming substrate 112 and is connected to a reservoir portion 136 described later.

  The vibration plate 114 includes an elastic film 131 provided on the upper surface of the flow path forming substrate 112 and a lower electrode film 132 provided on the upper surface of the elastic film 131. The elastic film 131 is made of, for example, silicon dioxide having a thickness of about 1 to 2 μm. Further, the lower electrode film 132 is made of, for example, platinum having a thickness of about 0.2 μm. The lower electrode film 132 is an electrode common to the piezoelectric element 113.

The piezoelectric element 113 includes a piezoelectric film 133 provided on the upper surface of the lower electrode film 132, an upper electrode film 134 provided on the upper surface of the piezoelectric film 133, and a lead electrode 135 that is a lead wiring of the upper electrode film 134. It has.
The piezoelectric film 133 is made of, for example, a metal oxide having a thickness of about 1 μm. The upper electrode film 134 is made of, for example, platinum having a thickness of about 0.1 μm. The lead electrode 135 is made of, for example, gold having a thickness of about 0.1 μm. An insulating film (not shown) is provided between the lead electrode 135 and the lower electrode film 132.

A plurality of piezoelectric elements 113 are provided so as to correspond to each of the plurality of nozzle openings 116 and the pressure generation chamber 118. That is, the piezoelectric element 113 is provided for each nozzle opening 116 (for each pressure generation chamber 118). As described above, the lower electrode film 132 functions as a common electrode for the plurality of piezoelectric elements 113, and the upper electrode film 134 and the lead electrode 135 function as individual electrodes for the plurality of piezoelectric elements 113.
In addition, a piezoelectric element group 113A is formed by a plurality of piezoelectric elements 113 provided side by side in the Y-axis direction so as to correspond to the nozzle openings 116 constituting the nozzle opening group 116A, and corresponds to the nozzle openings 116B. A piezoelectric element group 113 </ b> B is formed by the provided piezoelectric elements 113. A lead electrode group 135A is formed by the lead electrode 135 of the piezoelectric element 113 constituting the piezoelectric element group 113A, and a lead electrode group 135B is formed by the lead electrode 135 constituting the piezoelectric element group 113B.
The piezoelectric element 113 may include a lower electrode film 132 in addition to the piezoelectric film 133, the upper electrode film 134, and the lead electrode 135. That is, the lower electrode film 132 in the present embodiment may have a configuration that has both the function as the piezoelectric element 113 and the function as the diaphragm 114. In this embodiment, the diaphragm 114 is configured by the elastic film 131 and the lower electrode film 132. However, the elastic film 131 may be omitted, and the lower electrode film 132 may have the function of the elastic film 131.

  The reservoir forming substrate 115 is formed of, for example, a silicon single crystal that is the same material as the flow path forming substrate 112. Further, the reservoir forming substrate 115 is formed with a reservoir portion 136 corresponding to each of the communication portions 123 so as to extend in the Y-axis direction. The reservoir unit 136 and the communication unit 123 described above constitute the reservoir 121. The reservoir forming substrate 115 is formed with an introduction path 137 that is connected to the side wall of each communication portion 123 and introduces the functional liquid into each communication portion 123.

A compliance substrate 141 is bonded to the upper surface of the reservoir forming substrate 115. The compliance substrate 141 includes a sealing film 142 and a fixing plate 143.
The sealing film 142 is formed of a material having low rigidity and flexibility, such as a polyphenylene sulfide film having a thickness of about 6 μm, for example, and seals the upper portion of the reservoir portion 136.
The fixing plate 143 is formed of a hard material such as a metal such as stainless steel having a thickness of about 30 μm. A region of the fixing plate 143 corresponding to the reservoir 136 is an opening 145 that is completely removed in the thickness direction. Therefore, since the upper part of the reservoir part 136 is sealed only by the flexible sealing film 142, the flexible part 146 is deformable by a change in internal pressure. Further, on the compliance substrate 141 outside the reservoir portion 136, a functional liquid introduction port 147 for communicating with the introduction path 137 and supplying the functional liquid to the reservoir portion 136 is formed.

  Normally, when the functional liquid is supplied from the functional liquid introduction port 147 to the reservoir section 136, a pressure change occurs in the reservoir section 136 due to, for example, the flow of the functional liquid when the piezoelectric element 113 is driven or ambient heat. However, as described above, since the upper portion of the reservoir portion 136 is the flexible portion 146 sealed only by the sealing film 142, the flexible portion 146 is bent and deformed to absorb the pressure change. Therefore, the inside of the reservoir unit 136 is maintained at a constant pressure. The other portions are held with sufficient strength by the fixing plate 143.

Further, a groove 148 extending in the Y-axis direction is formed in the central portion of the reservoir forming substrate 115 in the X-axis direction. By this groove portion 148, the reservoir forming substrate 115 seals the sealing portion 149A for sealing the piezoelectric element group 113A corresponding to the pressure generating chamber group 118A and the sealing for sealing the piezoelectric element group 113B corresponding to the piezoelectric element group 113B. And 149B. A step portion is formed in the reservoir forming substrate 115 by the groove portion 148.
That is, in the reservoir forming substrate 115, a region facing the piezoelectric element 113 is formed with a piezoelectric element holding portion 150 that can seal the space while ensuring a space that does not hinder the movement of the piezoelectric element 113. ing. The piezoelectric element holding part 150 is formed in a size that covers the piezoelectric element groups 113A and 113B. Of the piezoelectric elements 113, at least the piezoelectric film 133 is sealed in the piezoelectric element holding unit 150.

  As described above, the reservoir forming substrate 115 functions as a sealing member for blocking the piezoelectric element 113 from the external environment and sealing the piezoelectric element 113. By sealing the piezoelectric element 113 with the reservoir formation substrate 115, it is possible to prevent the piezoelectric element 113 from being damaged by an external environment such as moisture. In the present embodiment, the inside of the piezoelectric element holding unit 150 is simply sealed. For example, the space in the piezoelectric element holding unit 150 is maintained in a vacuum, nitrogen, or argon atmosphere. The inside of the part 150 can be kept at low humidity, and the destruction of the piezoelectric element 113 can be prevented more reliably.

  As shown in FIG. 7, among the piezoelectric elements 113 sealed by the piezoelectric element holding portion 150, the end portion on the substrate center side of the lead electrode 135 is disposed on the flow path forming substrate 112 exposed in the groove portion 148. Has been. Here, a part of the lead electrode 135 positioned on the flow path forming substrate 112 exposed in the groove portion 148 in this way is an electrical connection portion of the piezoelectric element 113 in the present invention.

Next, a method for manufacturing the droplet discharge head 100 will be described. In the following description, a description of a method for manufacturing the FPC 101 and the head main body 102 will be omitted, and a method for connecting the FPC 101 and the head main body 102 will be described.
Also in the connection method between the FPC 101 and the head main body 102 in the present embodiment, the head main body 102 is mounted on the mounting table 2 and the anisotropic conductive film 109 is read as in the first embodiment described above. It sticks so that the whole electrode group 135A may be covered. Further, the FPC 101 is sandwiched between the grip portion 22 and the fixing portion 3.
And after performing a tension | tensile_strength addition process and a contact process like the above-mentioned, a heating-pressing process is performed. In this state, the support shaft 16 is further moved downward with the head portion 15 in contact with the FPC 101, thereby pressing the terminal portion 107A toward the lead electrode group 135A (FIG. 8). At this time, the anisotropic conductive film 56 is softened and melted by the heat supplied from the head portion 15, and the terminal portion 107A and the lead electrode group 135A are connected.
Thereafter, a releasing step is performed, and after the support shaft 16 is moved upward, the holding state of the FPC 101 by the grip portion 22 and the fixing portion 3 is released. Thereafter, a portion of the FPC 101 that is gripped by the grip portion 22 is excised. Note that this portion may be left as it is without being excised.
Further, the terminal portion 107A of the other FPC 101 and the lead electrode group 135B are connected by the same procedure.
As described above, the FPC 101 and the head main body 102 are connected, and the droplet discharge head 100 is manufactured.

The droplet discharge head 100 manufactured as described above is provided in, for example, a droplet discharge apparatus (electronic device) 160 as shown in FIG.
The droplet discharge device 160 includes a liquid crystal display device forming material for forming a liquid crystal display device, an organic EL forming material for forming an organic EL display device, and a wiring pattern for forming an electronic circuit wiring pattern. It is an apparatus that ejects droplets of a functional liquid such as a forming material. 9, the droplet discharge device 160 includes a droplet discharge head 100, first and second drive motors 161 and 162, a drive shaft 163, a guide shaft 164, a stage 165, and a cleaning device. A mechanism 166, a base 167, a heater 168, and an external controller 169 for controlling them are provided.

The first drive motor 161 is constituted by a stepping motor, for example, and is connected to the drive shaft 163. Then, the first drive motor 161 rotates the drive shaft 163 by the drive signal in the Y-axis direction supplied from the external controller 169 to move the droplet discharge head 100 in the Y-axis direction.
Similar to the first drive motor 161, the second drive motor 162 is configured by a stepping motor, for example, and is connected to the guide shaft 164. Then, the second drive motor 162 rotates the guide shaft 164 by the drive signal in the X-axis direction supplied from the external controller 169, and moves the stage 165 in the X-axis direction. The guide shaft 164 is fixed with respect to the base 167.
The stage 165 includes a fixing mechanism (not shown) that supports the substrate S on which the functional liquid is discharged from the droplet discharge head 100 and fixes the substrate S at a reference position.

The cleaning mechanism 166 cleans the droplet discharge head 100 and moves in the X-axis direction along the guide shaft 164 by driving of a drive motor (not shown).
The heater 168 heats the substrate S by lamp annealing, for example, and performs evaporation and drying of the solvent contained in the functional liquid applied to the substrate S.
The external controller 169 supplies drive signals to the first and second drive motors 161 and 162 and supplies a voltage for controlling droplet ejection by the droplet ejection head 100.

As described above, the wiring board connecting method, the wiring board connecting apparatus 1, the droplet discharge head 100, and the droplet discharge apparatus 150 according to the present embodiment also have the same operations and effects as the first embodiment described above. .
In the present embodiment, the ink is supplied to the reservoir 37 through one functional liquid introduction port 58 and the introduction path 52, but a plurality of functional liquid introduction ports are provided depending on the supply amount of the desired functional liquid. 58 and the introduction path 52 may be provided.
Further, the supply amount of the functional liquid may be adjusted by appropriately changing the opening area of the functional liquid introduction port 58.

In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, in the above embodiment, the tension is applied to the FPC in the direction along the extending direction of the first terminal electrode and the terminal electrode, but the direction of applying the tension to the FPC is not limited to this, and the first terminal electrode and the terminal are not limited thereto. Any direction that intersects the arrangement direction of the electrodes may be used.
Moreover, although the contact process is performed after the tension application process, the tension application process may be performed after the contact process.
In addition, an anisotropic conductive paste (ACP: Anisotropic paste) is used to connect the first terminal portion and the second terminal portion, and the terminal portion and the lead electrode group via an anisotropic conductive film. Conductive Paste) may be used, and other adhesives such as non-conductive film (NCF), non-conductive paste (NCP: Non Conductive Paste), and brazing material may be used for connection. Furthermore, you may connect by soldering. In addition, when the connection between the first terminal portion and the second terminal portion or the connection between the terminal portion and the lead electrode group is performed by alloy connection in the heating and pressurizing step, the adhesive may not be used.
Further, the tension adjusting unit may not be provided as long as the tension applied to the FPC can be in an appropriate state.

1 is a schematic diagram showing a wiring board connecting apparatus according to a first embodiment of the present invention. It is a disassembled perspective view which shows the mounting structure in 1st Embodiment. It is process drawing which shows the connection method of FPC in 1st Embodiment. Similarly, it is process drawing which shows the connection method of a wiring board. Similarly, it is process drawing which shows the connection method of a wiring board. It is an external view which shows a notebook personal computer provided with a mounting structure. It is sectional drawing which shows the droplet discharge head in 2nd Embodiment. It is process drawing which shows the connection method of FPC in 2nd Embodiment. It is an external view which shows a droplet discharge apparatus provided with a droplet discharge head.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiring board connection apparatus, 4 Heating pressurization part (heating pressurization means), 5 Tension addition part (tension addition means), 23 Tension adjustment part (tension adjustment means), 40 Mounting structure, 41, 101 FPC (flexible Conductive wiring board), 42 liquid crystal panel (object to be connected), 52, 106 wiring pattern, 53 first terminal portion, 55 first terminal electrode 56, 109 anisotropic conductive film (conductive adhesive), 67 second Terminal part, 100 Liquid droplet ejection head (mounting structure), 102 Head body part (object to be connected), 107 Terminal electrode (first terminal electrode), 107A, 107B Terminal electrode group (first terminal part), 135A, 135B Lead electrode group (second terminal part), 160 Liquid droplet ejection device (electronic device)

Claims (11)

A wiring board for connecting a first terminal portion composed of a plurality of linear first terminal electrodes provided at intervals to a flexible wiring board and a second terminal portion provided on a connection target. In the connection method,
A tension applying step of gripping the flexible wiring board and applying tension to the flexible wiring board in a direction along a direction intersecting with the arrangement direction of the first terminal electrodes;
A contact step of bringing the first terminal portion and the second terminal portion into contact with each other;
A heating and pressurizing step of pressing the first terminal portion toward the second terminal portion while heating and electrically connecting the flexible wiring board and the object to be connected. Wiring board connection method.   The wiring board connection method according to claim 1, wherein the contact step is performed after the tension applying step.   The wiring board connection according to claim 1 or 2, wherein in the tension applying step, a tension applied to the flexible wiring board is adjusted according to a dimensional change due to heating of the flexible wiring board. Method.   The wiring board connection method according to claim 1, further comprising a releasing step of releasing tension applied to the flexible wiring substrate after the heating and pressing step.   5. The wiring board connection method according to claim 1, wherein a conductive adhesive is interposed between the first terminal portion and the second terminal portion. 6. Wiring board connection for connecting a first terminal portion composed of a plurality of linear first terminal electrodes provided at intervals on a flexible wiring board and a second terminal portion provided on an object to be connected In the device
Tension applying means for holding the flexible wiring board and applying tension in a direction along a direction intersecting with the arrangement direction of the first terminal electrodes;
A wiring board connecting device, comprising: a heating and pressing unit that presses the first terminal portion while heating the flexible wiring substrate toward the second terminal portion in a state where tension is applied to the flexible wiring substrate.   7. The wiring board connecting device according to claim 6, wherein the tension applying means moves the gripped flexible wiring board in a direction along a direction intersecting with the arrangement direction of the first terminal electrodes.   The wiring board connecting device according to claim 6 or 7, wherein the tension applying means includes tension adjusting means for adjusting a tension applied to the flexible board in accordance with the flexible wiring board.   9. The device according to claim 6, further comprising a tension addition release control unit that releases a tension applied to the flexible wiring board after the first terminal portion is connected to the second terminal portion. The wiring board connecting device according to Item 1.   A mounting structure manufactured by using the wiring board connection method according to claim 1. An electronic apparatus comprising the mounting structure according to claim 10.

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