JPH10341076A - Mechanism for adjusting planar parallelism of thermocompression bonding tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate adjustment of the degree of planar parallelism of a thermocompression bonding tool in a short time, which the need for skill. SOLUTION: A tool base 26 having sufficient stiffness is fixed under a linkage unit, and expansion blocks 28 are mounted under the tool base through a heat insulator 27. Embedded into the block 28 are a constant heater 29 for adjustment of its expansion, as well as a thermocouple 30 acting as a temperature sensor. Both the heater 29 and thermocouple 30 are respectively separate by each expansion block and connected respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a compression bonding method used in a step of thermocompression bonding TCP on a liquid crystal panel or PWB and a step of pasting an ACF tape on the liquid crystal panel or PWB as a preceding step. The present invention relates to a thermocompression bonding tool for an apparatus. In other fields, the present invention can be applied to general crimping tools requiring fine adjustment of parallelism.

[0002]

2. Description of the Related Art When a driving circuit is mounted on a liquid crystal panel, as shown in FIG. 4, an ACF (Aeolotropic Contact Film) is used.
The liquid crystal panel 1 or PWB (Printed Wiri
In general, a method of connecting a TCP (Tape Carrier Package) 3 to an ng board 4 by thermocompression bonding is used. Here, the ACF tape is a tape-shaped member in which conductive particles are mixed in a resin film, PWB is a rigid wiring board,
CP is a liquid crystal drive IC on a tape on which a circuit pattern is formed.
Is a package manufactured by inner lead bonding.

When actually performing thermocompression bonding, as shown in FIG. 5, an object to be pressed is placed between a tool 55 as a heating element and a backup 56 as a support base, and the tool 55 is lowered to a specified pressure. Is done by adding At that time, in order to uniformly apply pressure to the object to be crimped, the plane parallelism between the tool 55 and the object to be crimped is important, and the distortion of the tool 55 shown in FIG. If the inclination of the tool 55 shown in FIG. Therefore, a mechanism for finely adjusting the plane parallelism of the crimping surface of the tool 55 so as to uniformly apply pressure to the object to be crimped is indispensable.

Here, a conventional technique will be described by taking an example of pressure bonding of a liquid crystal panel and TCP. T temporarily fixed on the liquid crystal panel
When the CP is fully press-bonded, small tools 58 are individually arranged for each TCP and pressurized by an air cylinder 61 as shown in FIG. A mechanism for adjusting the position is provided. The tool unit 62 that holds the tool 58 has a structure that rotates around a fulcrum 59, and uses a structure in which after adjusting the inclination of the tool unit 62 with the adjustment screw 57, the lock bolt 60 is tightened and fixed. . There is no adjustment mechanism for the distortion of the tool 58 itself, and since the length L1 of one side is short, distortion due to heat and the like is small.

Another parallel adjustment mechanism for such individual tools is disclosed in Japanese Patent Application Laid-Open No. Hei 8-114810, which is a patent for adjusting the inclination of a tool using a piezoelectric actuator.

Further, as another method, as shown in FIG. 8, there is a method of crimping a plurality of crimped portions at once using one long tool 66. This method does not require switching between models, and has the advantage of stabilizing the operation rate of the apparatus, but it is very difficult to perform parallel adjustment, and the inclination and distortion of the tool itself are reduced by pushing the adjustment screws 63 arranged on the upper surface of the tool 66. Fine adjustment by pulling and fixing by the fixing screw 64 are performed. The tool 66 itself is distorted due to tilt and heat,
If the pressure on the crimping surface is partially weakened, loosen the fixing screw 64 of the weakened portion, then turn the adjusting screw 63 to lower the adjusting screw, thereby tilting or deforming the tool block itself. Then, after removing the inclination and distortion, the fixing screw 64 is fixed again by re-tightening.

[0007]

In the method of arranging a plurality of small tools as shown in FIG. 7, since the tools 58 are individually installed in accordance with the position of the TCP, the type of the object to be crimped changes and the pitch between the TCPs changes. When the TCP width or number is changed, it is necessary to change the setup corresponding to the model such as position adjustment or replacement of the tool 58 each time. Tool 58 is T
Since it is necessary to manufacture according to the size of the CP, the manufacturing cost is high in order to support other models. Further, when the work such as the tool exchange or the change of the pitch P between the tools is performed, the parallelism of the crimping of the tool 58 may be deviated every time, and the pressure-sensitive paper which can express the degree of the pressure by the change in the density may be used. A check operation of actually crimping with the tool 58 is required for each replacement. If there was a deviation in the parallelism, the adjustment work took time.

Further, since there is a limit in reducing the size of the mechanism of an individual tool, when small TCPs are arranged at a narrow pitch, it is impossible to arrange the tools 58 in alignment with the TCPs. In this case, the number of the tools 58 is reduced, the tools 58 are arranged at intervals, and the liquid crystal panel is shifted a plurality of times to perform pressure bonding. As a result, the number of times of pressure bonding per one liquid crystal panel increases, resulting in a loss of time.

Further, it is difficult to make fine adjustments by adjusting the adjustment screw 57 shown in FIG. 7, and sometimes the parallel adjustment is slightly out of order when the lock bolt 60 is tightened after the adjustment.

On the other hand, in the method using one long tool 66 as shown in FIG. 8, since the length L2 of one side of the tool 66 is long, distortion due to heat of the tool 66 is inevitable. It is not possible to obtain the required crimp parallelism only by increasing the accuracy. Therefore, the adjustment screw 6
It is indispensable to adjust the distortion and inclination of the tool 66 after raising the temperature of the tool 66 to the actual use temperature by using the 3, but there is a limit in reducing the pitch of the adjustment screws 63 arranged in a large number. is there. Therefore, it is difficult to make a precise adjustment in units of several microns, and when the lock nut 65 is tightened to prevent the screw from being loosened after the adjustment is completed, the adjustment that was previously made during the locking operation may be slightly confused. was there. Further, since the torque for tightening the fixing bolt 64 affects the parallel adjustment, there is a problem that the operation requires skill, for example, the torque for tightening the fixing bolt 64 must be strictly controlled using a torque wrench.

An object of the present invention is to provide a plane parallelism adjusting mechanism of a thermocompression bonding tool which can perform adjustment of the plane parallelism of a thermocompression bonding tool in a short time without skill, and can perform precise adjustment. It is to be.

[0012]

According to a first aspect of the present invention, there is provided a tool for heating and pressing an object to be press-fitted, wherein a temperature-adjustable thermal expansion block is attached, and the degree of thermal expansion of the thermal expansion block is temperature-controlled. A plane parallelism adjusting mechanism for a thermocompression bonding tool, wherein a plane parallelism of a crimping surface of the tool can be adjusted.

According to a second aspect of the present invention, the thermal expansion block is provided integrally with the tool.
It is a plane parallelism adjustment mechanism of the thermocompression bonding tool described.

According to a third aspect of the present invention, there is provided the flat parallelism adjusting mechanism for a thermocompression bonding tool according to the first aspect, wherein a heat insulating material is interposed between the tool and the thermal expansion block.

According to a fourth aspect of the present invention, the thermal expansion block is mounted between the tool and a tool base for holding and raising and lowering the tool.
It is a plane parallelism adjustment mechanism mechanism of the thermocompression bonding tool of 2 or 3.

According to a fifth aspect of the present invention, a plurality of the thermal expansion blocks are arranged in parallel with the crimping surface of the tool, and the degree of thermal expansion is individually temperature-controlled. It is a plane parallelism adjustment mechanism of the thermocompression bonding tool of 3 or 4.

According to a sixth aspect of the present invention, the tool has a structure in which a slit is provided in a direction perpendicular to a crimping surface, and the tool can flexibly deform in response to a change in the thermal expansion block. A flat parallelism adjusting mechanism for a thermocompression bonding tool according to claim 1, 2, 3, 4, or 5.

According to the present invention, when adjusting the parallelism of the thermocompression bonding tool, no mechanical adjustment is required, and the degree of thermal expansion can be reduced only by changing the temperature setting of the temperature controller of each expansion block. By adjusting, the inclination of the parallelism of the pressing surface of the tool and the warp of the tool itself can be changed. Since the change in the tool distortion due to the change in the temperature setting is very small, fine parallel adjustment of the tool pressing surface in units of microns can be easily performed. Since the mechanical locking work after the adjustment is not required, the parallelism does not change due to the locking work after the adjustment is completed.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B are configuration diagrams showing a crimping portion of a TCP crimping apparatus using a plane parallelism adjusting mechanism of a thermocompression bonding tool according to the present invention, wherein FIG. 1A is a front view thereof, and FIG. FIG.

The liquid crystal panel 1 which has been preliminarily crimped by aligning the TCP 4 in the previous step is suction-fixed to the panel stage 16. The panel stage 16 can be freely positioned by a motor-driven XY table (not shown), and moves so that a portion to be crimped is located below the tool 5. A backup 6 is provided below the crimping portion of the panel 1 to receive the load of the tool 5.

A column 18 is erected on the entire base 17, and a vertical base 19 is attached to the column 18. A guide 20 having a slide mechanism is fixed on the vertical base 19, and the connecting unit 21 mounted on the guide 20 can slide up and down according to the guide 20. The connection unit 21 is connected to an air cylinder 22 installed at an upper portion, a joint 23 and a connection shaft 24. Although not shown here, the joint 23 absorbs the misalignment of the axis even if the axes of both the drive shaft 25 of the air cylinder 22 and the connection shaft 24 are not completely aligned, and a mechanical load is applied to the cylinder 22. There is a built-in mechanism that does not work.

Next, the tool unit will be described with reference to FIG. A tool base 26 having a sufficient rigidity is fixed below the connecting unit 21, and an expansion block 28 is attached to a lower side of the tool base 26 via a heat insulating material 27. The expansion block 28 includes a constant heater 29 for adjusting the degree of expansion and a thermocouple 30 serving as a temperature sensor.
Are embedded, and the constant heater 29 and the thermocouple 30 are both separated for each expansion block and connected as shown in FIG.

The tool 5 is mounted below the expansion block 28 via a heat insulating material 31. A constant heater 32 and a thermocouple 33 for heating are embedded in the tool 5, and each is connected to a temperature control circuit 36 shown in FIG. The tool 5 has a structure in which a slit 34 is provided. A radius 35 is provided at the root of the slit 34 to prevent bending stress from concentrating on the root of the slit 34 to prevent the tool 5 from being fatigued. The slits 34 allow the distortion of the tool 5 to be freely changed, thereby giving the tool 5 flexibility without reducing the heat capacity of the tool 5 itself, that is, the volume of the tool 5.

Next, the operation of this device will be described. When the temperature of the tool is increased, the thermal expansion of the tool itself causes
A distortion h as shown in FIG. In this state, when the parallelism of the tool is measured using the above-described pressure-sensitive paper, it can be confirmed that the pressure at the center of the tool is strong and the ends are weak. here,
To correct the distortion h, the temperature settings of the expansion blocks 28a, 28b, 28g, 28h in FIG. 2 are increased by a certain amount. Thereby, the expansion blocks 28a, 28b,
The temperature of 28 g and 28 h rises, and each expansion block expands due to heat, and the interval T between the tool base 26 and the tool 5 expands only at both ends. Since the tool base 26 has sufficient rigidity as compared with the tool 5, a force acts on the tool 5 in a direction to eliminate the distortion h in FIG.

On the other hand, 28a the temperature setting if the entire tool inclination x _theta occurs in the lateral direction as viewed from the tool front expansion block as shown in FIG. 6 (b) = 28b> 28c = 28d> 28e = 28f> 2
By setting so that 8g = 28h, the inclination of the entire tool can be adjusted. Similarly, it is possible to adjust the inclination in the front-back direction when viewed from the front of the tool.

The amount of expansion of the expansion block 28 in the vertical direction used in the above embodiment is expressed by the following equation. Δh = αhΔt where, h: height of expansion block Δh: expansion amount of expansion block α: linear expansion coefficient of material Δt: changed temperature

Therefore, when an expansion block made of stainless steel having a height of 60 mm (coefficient of linear expansion: 17 × 10 ⁻⁶ ) is used, the amount of expansion when the temperature setting is changed by 1 ° C. is Δh = 17 × 10 ⁻⁶ × 60 × 1 = 0.00102 (mm) It can be seen that if it is desired to change the height of the expansion block by about 1 μm, the temperature setting should be changed by 1 ° C.

Thus, since the temperature of the thermal expansion blocks can be controlled individually, each thermal expansion block can have a different degree of expansion according to each set temperature. As a result, the tool located below the expansion block can adjust the inclination as a whole according to each expansion block, and can change the distortion of the tool. In addition, one side of a plurality of TCPs can be collectively crimped with one tool, and it is not necessary to switch the tool type according to the production model as compared with the TCP individual crimping tool.
Since there is no need to perform adjustment confirmation work accompanying model switching, there is the effect of reducing equipment costs and improving productivity.

Next, an embodiment of a plane parallelism adjusting mechanism of another thermocompression bonding tool will be described. FIG. 3 shows a configuration diagram of the tool unit portion. Except for the heat-generating portion of the tool and the parallel adjustment portion by the expansion block, they are the same as those in the above-described embodiment, and thus will not be described here.

In this embodiment, the tool 39 is directly mounted below the tool base 40, and the role of the expansion block is given to the tool 39 itself. Therefore, the constant heater 38 has both a role of heating the tool 39 and a role of controlling the degree of partial expansion of the tool 39. Here, the temperature of the constant heater 38 and the thermocouple 37 are individually controlled in the same manner as in the previous embodiment. There is an advantage that the structure is simple as compared with the above-described embodiment. However, if the temperature of the heater 38 is changed for the parallel adjustment, the temperature of the pressing surface of the tool 39 is affected, so that the temperature distribution of the tool 39 cannot be strictly uniform. Therefore, it is not suitable for applications where the range of the pressing temperature condition is small.

As described above, in the present embodiment, the number of dilation blocks is eight, but the present invention is not limited to this. The number of dilation blocks can be increased or decreased. The number of expanded blocks, the arrangement position, and the like may be changed without departing from the spirit.

[0033]

As described above, according to the first aspect of the present invention, the thermal expansion block is attached to the tool, and the plane parallelism of the crimping surface of the tool is adjusted by the thermal expansion of the thermal expansion block. Unlike the adjustment of the inclination and distortion of the tool, which has been performed with the adjustment screw, the adjustment time is short without skill, and the precise adjustment is possible.

According to the second aspect of the present invention, since the thermal expansion block is provided integrally with the tool, the thermal expansion accompanying the heat generation of the tool is controlled separately for each part of the tool, thereby enabling parallel adjustment of the tool. Available.

According to the third aspect of the present invention, since the heat insulating material is interposed between the tool and the thermal expansion block, the temperature of the thermal expansion block is transmitted to the tool and does not affect the temperature of the tool.

According to the fourth aspect of the present invention, since the expansion block is provided between the tool and the tool base supporting the tool,
Achieves parallelism adjustment of the crimping surface of the tool without a mechanical adjustment mechanism.Since it is an integrated unit without a mechanical adjustment mechanism, it can be out of order due to locking after adjustment, mechanical backlash, etc. There is also an effect that time-dependent changes due to the above do not occur.

According to the fifth aspect of the invention, by individually changing the degree of expansion of the plurality of expansion blocks, not only the inclination of the tool but also the distortion of the tool itself can be adjusted three-dimensionally.

According to the invention of claim 6, the tool and:
Between the tool base that holds and raises and lowers the tool,
Since the slit provided with the thermal expansion block is provided, it is possible to flexibly follow the change of the thermal expansion block without lowering the heat capacity of the tool itself, that is, without reducing the volume of the tool, and to adjust the plane parallelism of the crimping surface. Can be sufficiently utilized in a short time and with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a crimping portion of a TCP crimping apparatus using a plane parallelism adjusting mechanism of a thermocompression bonding tool according to the present invention.

FIG. 2 is a perspective view showing a tool part.

FIG. 3 is a perspective view showing another example of a tool portion.

FIG. 4 is a configuration diagram in which a driving circuit is mounted on a liquid crystal panel.

FIG. 5 is an explanatory diagram showing an operation of pressing a TCF on a liquid crystal panel.

FIG. 6 is an explanatory diagram showing a tool failure state.

FIG. 7 is a configuration diagram showing a structure of a conventional tool portion.

FIG. 8 is a configuration diagram showing another structure of a conventional tool portion.

[Explanation of symbols]

 5 Tool 26 Tool Base 27 Heat Insulation Material 28a-28h Expansion Block 29 Constant Heater 36 Temperature Control Circuit

Claims (6)

[Claims] 1. A temperature-adjustable thermal expansion block is attached to a tool that heats and presses an object to be pressed, the degree of thermal expansion of the thermal expansion block is temperature-controlled, and the plane parallelism of a pressing surface of the tool is adjusted. A parallelism adjusting mechanism for a thermocompression bonding tool. 2. The plane parallelism adjusting mechanism for a thermocompression bonding tool according to claim 1, wherein said thermal expansion block is provided integrally with said tool. 3. A flat parallelism adjusting mechanism for a thermocompression bonding tool according to claim 1, wherein a heat insulating material is interposed between said tool and said thermal expansion block. 4. The thermocompression bonding tool according to claim 1, wherein the thermal expansion block is attached between the tool and a tool base that holds and raises and lowers the tool. Degree adjustment mechanism mechanism. 5. The thermal expansion block according to claim 1, 2, 3 or 4, wherein a plurality of thermal expansion blocks are arranged in parallel to the crimping surface of the tool, and the degree of thermal expansion is individually controlled. Plane parallelism adjustment mechanism for thermocompression bonding tools. 6. The tool according to claim 1, wherein the tool is provided with a slit in a direction perpendicular to a crimping surface, and the tool can be flexibly deformed in response to a change in the thermal expansion block. The parallelism adjusting mechanism of the thermocompression bonding tool according to 2, 3, 4 or 5.