JP2888073B2 - Thermocompression bonding device and thermocompression bonding method for tab device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermocompression bonding device and a thermocompression method for a tab device for thermocompression bonding a lead of a tab device to an electrode of a display panel.

[0002]

2. Description of the Related Art A display panel such as a liquid crystal panel frequently used in a display device or the like is assembled by thermocompression bonding an electrode of a driver to an electrode formed on a side edge portion thereof. A tab device is frequently used as a driver. The tab device uses the TAB method (Tape Automated B
A device made by an onding method, in which a chip cut from a wafer is bonded to a lead attached to a film carrier made of a synthetic resin such as polyimide.

FIG. 11 shows a main portion of a conventional thermocompression bonding apparatus for thermocompression bonding a tab device as a driver to a display panel. Next, a conventional thermocompression bonding method for a tab device will be described with reference to FIG. . The display panel 1 is placed on a table 8. Further, a thermocompression bonding head 9 is arranged above the display panel 1. A film carrier 5 of a tab device 4 is temporarily attached on an electrode (not shown) at a side edge of the display panel 1 in advance. A lead (not shown) is adhered to the lower surface of the film carrier 5, and the lead is aligned with the electrode of the display panel 1 and temporarily attached. Reference numeral 6 denotes a chip bonded to the film carrier 5. The planar shape of the display panel 1 is generally rectangular, and a plurality of (four in this embodiment) are provided on the side edges thereof.
Are bonded. Therefore, the thermocompression bonding head 9 is horizontally moved in the X direction or the Y direction by a moving table (not shown) to be positioned directly above the tab device 4, and is lowered there by strongly pressing the leads of the film carrier 5 against the electrodes of the display panel 1. Thermocompression bonding (see chain line in the figure).

However, since such a conventional thermocompression bonding apparatus is provided with only one thermocompression bonding head 9, a plurality of tab devices 4 are thermocompression bonded to the display panel 1 one by one with the thermocompression head 9. And there is a problem that work efficiency is not improved.

[0005]

As means for solving such a problem, it is conceivable to provide a plurality of thermocompression bonding heads 9 as shown in FIG. In this way, the work efficiency can be improved by simultaneously thermocompression bonding the plurality of tab devices 4 to the display panel 1 by the plurality of thermocompression heads 9.

[0006] However, as shown in FIG.
Since many are bent and formed of a relatively weak material such as glass, when the plurality of thermocompression bonding heads 9 are simultaneously lowered to strongly press the film carrier 5 against the display panel 1, the display will be stopped. There is a new problem that the panel 1 is broken.

Accordingly, the present invention provides a thermocompression bonding device for a tab device that can simultaneously thermocompress a plurality of tab devices by a plurality of thermocompression heads so that the display panel is not broken even if the display panel is bent. And a thermocompression bonding method.

[0008]

For this purpose, a thermocompression bonding apparatus for a tab device according to the present invention has a plurality of thermocompression heads arranged in parallel and each thermocompression bonding element is arranged on the same straight line. In addition, each of the thermocompression bonding elements is individually pressed by the driving of each pressing means.

[0009]

According to the above-mentioned structure, a strong pressing force is not applied to a plurality of thermocompressors at the same time, but a strong pressing force is sequentially applied with a time lag, or the applied state of the strong pressing force is released. Thereby, the plurality of tab devices can be thermocompression-bonded to the display panel with good workability while correcting the deflection of the display panel little by little.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an overall perspective view of a thermocompression bonding apparatus for a tab device according to one embodiment of the present invention. This thermocompression bonding device for a tab device is configured by erecting a support post 12 on a main body box 11. An X table 13 and a Y table 14 which are orthogonal to each other are provided on the main body box 11, and a table 15 on which the display panel 1 is mounted is provided on the Y table 14. A tab device 4 as a driver is temporarily attached in advance on an electrode on a side edge of the display panel 1.

The display panel 1 has a rectangular planar shape. As shown in the figure, four tab devices 4 are temporarily attached to the edge of the long side, and 2 tabs are attached to the edge of the short side. The tab devices 4 are temporarily attached. The display panel 1 is made of glass, and is likely to be slightly bent, but generally the deflection in the long side direction is considerably larger than the deflection in the short side direction.

When the X direction motor 16 provided on the X table 13 is driven, the display panel 1 moves horizontally in the X direction,
When the Y direction motor 17 provided on the Y table 14 is driven, the display panel 1 moves horizontally in the Y direction. Reference numeral 18 denotes a conveyor that carries the display panel 1 onto and off the base 15.

The support post 12 is provided with a plurality of thermocompression heads 20. Display panel 1 as described above
Four tab devices 4 are temporarily attached to the edge of the long side (X direction), and two tab devices 4 are temporarily attached to the edge of the short side (Y direction). In the X direction, four thermocompression bonding heads 20 are arranged on the same straight line, and two thermocompression bonding heads 2 are arranged in the Y direction.
0 are juxtaposed on the same straight line. Of course, display panel 1
Is provided, the tab devices 4 on the sides orthogonal to each other of the display panel 1 can be thermocompression-bonded by the thermocompression heads 20 on the long side and the two thermocompression heads 20 on the short side. Can be eliminated.

Next, the structure of the thermocompression bonding head 20 will be described in detail with reference to FIGS. In FIG. 2, reference numeral 21 denotes a bracket held by the support post 12, to which components described below are assembled. Bracket 21
A shelf 22 is horizontally protruded from the center of the front surface of the device, and an air cylinder 23 is installed on the shelf 22. As shown in FIG. 4, a rod 24 of the air cylinder 23 penetrates the shelf 22, and a fitting 25 formed at an upper portion of a lifting / lowering body 26 fits into a fitting 25 connected to a lower end thereof. I agree. A pressure-sensitive element 28 such as a load cell is provided inside the fitting portion 27. The metal fitting 25 is grounded to the pressure sensing portion 29 of the pressure sensing element 28,
The pressing force due to the protrusion of the third rod 24 is detected.

A slider 31 is mounted on the back surface of the elevating body 26. The slider 31 is fitted on a vertical guide rail 32 provided on the front surface of the bracket 21. Therefore, when the rod 24 of the air cylinder 23 projects downward, the elevating body 26 descends along the guide rail 32, and when the rod 24 is pulled upward, the elevating body 26 ascends along the guide rail 32. In FIG. 2, tubes 33 and 34 for supplying or exhausting air to and from the air cylinder 23 are connected to an electropneumatic regulator 44 (described later).

In FIG. 3, reference numeral 35 denotes a thermocompression contact,
The upper central portion is pivotally attached to the lower part of the elevating body 26 by a pin 36, and the thermocompression bonding element 35 can swing slightly around the pin 36 in the direction of the arrow. Reference numeral 39 denotes a bearing that is grounded on the upper surface of the thermocompression contact 35, and reference numeral 40 denotes a bearing that connects the bearing 39 to the thermocompression contact 35.
A coil spring for pressing against the upper surface of the
Prevent 5 rattling. By configuring the thermocompression crimping device 35 to be able to swing slightly, even if the upper surface of the display panel 1 is inclined, the thermocompression crimping device 35 swings around the pin 36 in accordance with this. Lower surface is film carrier 5
Is firmly grounded to the upper surface of the display panel 1 so that all the leads 7 can be pressed against the electrodes 2 of the display panel 1 with an equal force.

In FIG. 4, the cross-sectional shape of the thermocompression bonding element 35 includes a central enlarged portion 35a, a grounded portion 35b having a small cross-sectional area connected to a lower portion of the enlarged portion 35a, and an upper portion of the enlarged portion 35a. And a mounting portion 35c which is connected to the pin 36 and is axially mounted on the pin 36. Huge part 35
A heater 37 as a heating means and a temperature sensor 38 are buried inside a. The thermocompression bonding element 35 is heated by the heater 37.
By burying and heating in 5a, the expanded portion 35a is used as a heat storage portion.

In FIG. 3 and FIG. 4, a pipe 41 as cooling means is disposed behind the ground portion 35b in parallel with the ground portion 35b. 43 is a fixture for the pipe 41. The pipe 41 has cool air outlets 42 at intervals. This pipe 41 is a compressor 4
5 (to be described later), and blows cool air toward the film carrier 5 near the grounding portion 35b to partially cool it.

FIG. 5 is a piping diagram of the thermocompression bonding head of the tab device according to one embodiment of the present invention. In the figure, reference numeral 20 denotes the thermocompression bonding head. As shown in FIG.
However, only two thermocompression bonding heads 20 are shown in FIG. 5 because they have the same structure. The air cylinder 23 is
It is connected to a compressor 45 via an electropneumatic regulator 44. The pipe 41 is connected to a compressor 45 via a valve 46, and switches on and off of the valve 46 to switch between cooling and stopping cooling of the film carrier 5. Therefore, in this embodiment, the control of the air cylinder 23 and the blowing of cool air from the pipe 41 are performed by the same compressor 45.

FIG. 6 is a block diagram of an electric circuit of the thermocompression bonding head of the tab device according to one embodiment of the present invention. As shown in FIG. 1, there are six thermocompression bonding heads 20, but since all have the same structure, FIG. 6 shows only two thermocompression bonding heads 20. Heater 37 of thermocompression bonding head 20 and temperature sensor 3
8 is connected to a control unit 48 via a temperature controller 47. The electropneumatic regulator 44, the pressure-sensitive element 28,
The valve 46 is connected to the control unit 48. The control unit 48 is a CPU, and performs necessary control while reading necessary data such as program data registered in the memory 49. The control unit 48 controls the X-direction motor 16 and the Y-direction motor 17 for driving the X table 13 and the Y table 14 via a motor driver 50.

Next, the operation of the thermocompression bonding head 20 will be described with reference to the operation diagram of FIG. 7 and the time chart of FIG. Initially, the thermocompression bonding element 35 is at the ascending position shown in FIG. 7A, and the expanded portion 35a is preheated to about 200 ° C. by the heater 37. When the rod 24 of the air cylinder 23 is protruded downward at the timing t1, the thermocompression bonding member 35 descends, and the grounding portion 35b grounds the film carrier 5 with a small force (see FIG. 7B). If the thermocompression contactor 35 is grounded to the film carrier 5 with a weak force as described above, it is possible to prevent the display panel 1 from being damaged by an impact at the time of grounding. At this time, the pressure-sensitive value of the pressure-sensitive element 28 is 1.0.
kg / cm ² . Simultaneously with the grounding, the valve 46 is opened, and cool air is blown from the blow-out hole 42 to the upper surface of the film carrier 5 near the grounding portion 35b. Is pressed by the thermocompression bonding element 35.

Subsequently, at time t2, the air cylinder 23
The pressing force is 2.0
kg / cm ² or more (timing t
2), the lead 7 is strongly pressed by the electrode 2 of the display panel 1; At the same time, the valve 46 is closed and the film carrier 5 is blown by blowing cool air from the blow hole 42 of the pipe 41.
Is stopped, and the temperature of the film carrier 5 rises rapidly. When the heating of the film carrier 5 and the pressing state with a strong force by the grounding portion 35b are held for a certain period of time in this way, the conductive sheet 3 is cured at the timing t3,
At timing t4 immediately after that, the air cylinder 23
The rod 24 is retracted, the thermocompressor 35 starts to rise and releases the pressed state against the film carrier 5, and a series of operations ends. The cycle time T is about 30 seconds.

In the above operation, while the lead 7 is pressed against the electrode 2 with a weak force (1.0 kg / cm ² ), cool air is blown to the film carrier 5 to prevent its temperature from rising, and Force with sufficient pressure (2.0kg / cm
² ), the cooling of the film carrier 5 is stopped when there is no risk of the displacement of the lead 7.
Is eliminated, and the lead 7 is thermocompression-bonded to the electrode 2 of the display panel 1 while being properly matched. Note that the cooling start timing t1 and the cooling release timing t2 are not limited to the present embodiment, and may be slightly shifted. In short, the cooling is performed while the film carrier 5 is likely to be thermally deformed. If there is no risk of displacement due to thermal deformation, the cooling may be released, and cool air may be blown while the thermocompression bonding element 35 shown in FIG.

Each of the thermocompression heads 20 operates as described above. Next, a method of thermocompression bonding a plurality of tab devices 4 to the display panel 1 by a plurality of thermocompression heads 20 will be described. In FIG. 1, the X direction motor 16 and the Y direction motor 17 are driven to horizontally move the display panel 1 in the X direction and the Y direction, and the four tab devices 4 temporarily attached to the long side edges are used. The thermocompression heads 20 of the four thermocompression heads 20 arranged in a straight line are moved directly below the thermocompression elements 35. Next, the following operation will be described with reference to FIG.

FIG. 9 is a view for explaining the operation of the thermocompression bonding elements 35 of the four thermocompression bonding heads 20 arranged in parallel in the x direction. The four thermocompression bonding elements 35 are 1, 2, 3, 4 Are distinguished by subscripts. FIG. 9A shows a state in which the film carriers 5 of the four tab devices 4 have been moved just below the thermocompression bonding elements 351 to 354 of the four thermocompression bonding heads 20 as described above. As shown, the display panel 1 is bent in a downward convex shape.

As shown in FIG. 9 (b), the two thermocompression bonding elements 352 and 353 are formed by projecting the rods 24 of the air cylinders 23 of the two thermocompression bonding heads 20 at the center.
At the same time to make the film carrier 5 contact the ground with a weak force. The pressing force of each of the thermocompression bonding members 352 and 353 at this time is about 1.0 kg / cm ² . Subsequently, the pressing force of the rod 24 of the air cylinder 23 is increased to 2.0 kg / cm ² ,
Is strongly pressed against the electrode 2. When the thermocompression bonding by the central thermocompression bonding members 352 and 353 is completed in this way, the thermocompression bonding is next performed by the two left and right thermocompression bonding devices 351 and 354. The thermocompression bonding by the left and right thermocompression bonding members 351 and 354 is the same as the thermocompression bonding by the center thermocompression bonding members 352 and 353. After the landing is performed with a weak force as shown in FIG. Press. Note that the left and right thermocompressors 351 and 354
During the thermocompression bonding, the strong pressing state of the center thermocompression 352, 353 already thermocompressed may be released,
Alternatively, it may be continued.

When the thermocompression bonding by the thermocompression bonding elements 351 and 354 is completed, the rods 2 of all the cylinders 23
4 is retracted to return to the initial state shown in FIG. As described above, the four thermocompressors 351 to 354 are not pressed against the film carriers 5 of the four tab devices 4 at the same time strongly, and the four thermocompressors 351 to 354 are grouped into several groups (in this embodiment, (The two groups of the thermocompression elements 352 and 353 and the thermocompression elements 351 and 354), and if the pressure is strongly applied in the order of time, the cracks of the display panel 1 can be prevented and the deflection can be corrected. Thermocompression bonding can be performed.

As described above, the bending of the short side of the display panel 1 is considerably smaller than the bending of the long side. Therefore, the two tab devices 4 on the short side may be simultaneously pressed strongly by the two thermocompression heads 20 to perform thermocompression.

FIG. 10 shows a thermocompression bonding method when the display panel 1 is bent in an upward convex shape. Also in this case, FIG.
Thermocompression bonding is performed in the same manner as in the above case. That is, FIG.
As shown in (a), the film carrier 5 of the display panel 1
Are located immediately below the four thermocompression bonding elements 351 to 354, and then, as shown in FIG.
And the left and right thermocompressors 351 and 354 are grounded to the respective film carriers 5 with a weak force. Then, the pressing force is increased and the thermocompressors 351 and 354 are used to perform thermocompression bonding in the same manner as described above. I do. Next, after the same thermocompression bonding is performed by the two central thermocompression bonding members 352 and 353 (FIG. 10C), all the thermocompression bonding members 351 to 354 are raised and the initial state of FIG. Return to.

The operating method of this thermocompression bonding apparatus is not limited to the above-mentioned embodiment, and various methods are conceivable. In short, it is not necessary to simultaneously press all thermocompression bonding elements 35 against the display panel 1 with a strong force. It is sufficient to perform the thermocompression bonding while correcting the deflection of the display panel 1 by strongly pressing the sub-elements 35 back and forth with time, and furthermore, there is a possibility that the lead 7 may be displaced due to the thermal deformation of the film carrier 5. Until the film carrier 5 runs out, it is desirable to cool the film carrier 5 by blowing cold air from the pipe 41.

[0032]

As described above, according to the present invention, a strong pressing force is applied to a plurality of thermocompression bonding elements in time order without applying a strong pressing force simultaneously. By releasing the pressure application state, the plurality of tab devices can be thermocompression-bonded to the display panel with good workability while correcting the deflection of the display panel little by little.

[Brief description of the drawings]

FIG. 1 is a perspective view of a thermocompression bonding apparatus for a tab device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 3 is a front view of a thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 4 is a sectional view of a thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 5 is a piping diagram of a thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 6 is a block diagram of an electric circuit of the thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 7A is a partially enlarged side view of the thermocompression bonding head of the tab device according to one embodiment of the present invention during operation. FIG. Side view (c) Partially enlarged side view during operation of the thermocompression bonding head of the tab device according to one embodiment of the present invention.

FIG. 8 is a time chart of the operation of the thermocompression bonding head of the tab device according to one embodiment of the present invention.

9A is a front view of a display panel and a thermocompression bonding element during thermocompression bonding according to an embodiment of the present invention. FIG. 9B is a front view of a display panel and a thermocompression bonding element during thermocompression bonding according to an embodiment of the invention. (C) Front view of display panel and thermocompression element during thermocompression bonding according to one embodiment of the present invention

10A is a front view of a display panel and a thermocompression bonding element during thermocompression bonding according to an embodiment of the present invention. FIG. 10B is a front view of a display panel and a thermocompression bonding element during thermocompression bonding according to an embodiment of the invention. (C) Front view of display panel and thermocompression element during thermocompression bonding according to one embodiment of the present invention

FIG. 11 is a front view of a display panel and a thermocompression element during conventional thermocompression bonding.

FIG. 12 is a front view of a display panel and a thermocompression element during conventional thermocompression bonding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display panel 2 Electrode 4 Tab device 7 Lead 20 Thermocompression head 23 Air cylinder 35 Thermocompression contact 37 Heater 48 Control part

Claims (3)

(57) [Claims] 1. A thermocompression head for thermocompression-bonding a lead of the tab device to an electrode of the display panel, comprising: a base for mounting a display panel to which a tab device is temporarily attached; A thermocompression element, a pressing means for vertically moving the thermocompression element to press the lead against the electrode, and a heating means for heating the thermocompression element; Thermocompression bonding of a tab device, wherein the thermocompression bonding elements are arranged so as to be positioned on the same straight line, and each of the thermocompression bonding elements is individually pressed by the driving of each pressing means. Apparatus and thermocompression bonding method. 2. The apparatus according to claim 1, wherein said pressing means is an air cylinder, and a pressing force of said thermocompression contact is changed by changing an air pressure applied from said compressor to said air cylinder. Thermocompression device and thermocompression method for tab device. 3. A pressing means is driven to lower a plurality of thermocompression elements heated by the heating means, and these thermocompression elements are pressed by a small force on a tab device temporarily attached on an electrode of a display panel. Grounding; and increasing the pressing force of the plurality of thermocompressors back and forth with time to strongly press the lead of the tab device against the electrode. Crimping device and thermocompression bonding method.