JP3799378B2 - Substrate assembly method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for assembling substrates to be bonded to each other by holding the substrates to be bonded in a vacuum chamber so that the substrates are opposed to each other and the interval is reduced in a vacuum.
[0002]
[Prior art]
For the production of liquid crystal display panels, two glass substrates provided with transparent electrodes and thin film transistor arrays are bonded with an adhesive (hereinafter also referred to as a sealing agent) with a very close distance of about several μm (hereinafter referred to as bonding). The later substrate is called a cell), and there is a step of sealing the liquid crystal in the space formed thereby.
[0003]
For sealing the liquid crystal, the liquid crystal is dropped on one substrate drawn in a pattern in which a sealing agent is closed so as not to provide an injection port, and the other substrate is placed on one substrate and placed in a vacuum. The method proposed in Japanese Patent Application Laid-Open No. Sho 62-165622, in which the upper and lower substrates are brought close together, and the substrate is bonded in a vacuum by patterning a sealing agent so as to provide an injection port on one of the substrates. After that, there is a method proposed in Japanese Patent Laid-Open No. 10-26763 in which liquid crystal is injected from an injection port.
[0004]
[Problems to be solved by the invention]
In the above prior art, both substrates are bonded in a vacuum regardless of before and after the pattern drawing of the sealant, but in vacuum, the substrates are sucked and adsorbed by a pressure difference from the atmosphere as in the atmospheric state. I can't.
[0005]
Therefore, when the end portion of the upper substrate (hereinafter referred to as the upper substrate) is mechanically held, the central portion of the substrate is bent, and the deflection becomes larger as the recent trend toward larger and thinner substrates increases. ing.
[0006]
Before bonding, optical positioning is performed using alignment marks provided on the peripheral edges (ends) of the upper and lower substrates, but as the deflection increases, the distance between the ends of both substrates increases. This makes it difficult to focus on the alignment mark, making accurate alignment difficult.
[0007]
In addition, when bonding, the central portion of the upper substrate that is bent contacts the lower substrate (hereinafter referred to as the lower substrate) before the peripheral portion, so that the substrate can be kept constant. The spacers dispersed in between move and damage the alignment film formed on the substrate.
[0008]
The present invention has been made in view of the above-mentioned circumstances,
Even if the substrate size is large or thin, it can be bonded with high precision in a vacuum.
Even if the adhesive is provided near the periphery of the substrate, the upper substrate can be easily held,
And it is possible to bond without damaging the alignment film,
In particular, the present invention provides a substrate assembling method and apparatus capable of quickly and easily peeling a bonded substrate (cell) from an adhesive as a substrate holding means.
[0011]
[Means for Solving the Problems]
The present invention to achieve the above object, are opposed to each other and held on the other substrate to be bonded to one of the substrates to be bonded, the assembly method of a substrate to be bonded in a vacuum by an adhesive provided without Re of the substrate have The first feature is that one of the substrates is held by an adhesive means built in the pressure plate, and after being bonded to the other substrate, the adhesive means is retracted into the pressure plate.
The present invention, a pressing plate for holding one substrate above the vacuum chamber, provided with a table which holds the other substrate beneath the vacuum chamber, Re not want to keep the the pressurized pressure plate and the table in the assembly device for the substrate to align Ri adhered to substrates to each other by narrowing the distance between both substrates in a vacuum by an adhesive provided on the Kano substrate, and a shaft which expands and contracts with a plurality of actuators and the actuator in said pressure plate provided the earlier the adhesive member of the shaft is provided, in that the one substrate in the adhesion to the lower surface of the adhesive member is configured to hold in close contact to the lower surface of the pressure plate and the second feature, the substrate In the assembling apparatus, after the one substrate held by the pressure plate and the other substrate held on the table are bonded to each other with a small gap, the shaft is attached to the pressure plate using the actuator. The adhesive member by retracting retracting into the pressure plate to a third feature that it has a configuration in which peeling the adhesive member from the substrate surface.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2, a substrate assembly apparatus 1 according to the present invention includes a lower chamber portion T1 and an upper chamber portion T2, and an XYθ drive mechanism (not shown) is provided below the lower chamber portion T1. It has been. With this XY drive mechanism, the lower chamber portion T1 can come and go in the left and right X-axis directions and the Y-axis direction orthogonal to the X-axis in the drawing. Further, the table 4 on which the lower substrate 1a is mounted from the shaft 2 through the vacuum seal 3 can be horizontally rotated with respect to the lower chamber unit 5 by the θ drive mechanism. The lower substrate 1a, when mounted on the table 4, has a structure that is mechanically positioned and fixed by pins, rollers, and the like and a structure that is sucked and sucked. For simplicity, these structures are illustrated. Is omitted.
[0013]
The upper chamber unit T2 has a structure in which the upper chamber unit 6 and the pressure plate 7 therein can be moved up and down independently. That is, the upper chamber unit 6 has a housing 8 incorporating a linear bush and a vacuum seal, and moves in the vertical Z-axis direction by a cylinder 11 fixed to the frame 10 with a shaft 9 as a guide.
[0014]
When the lower chamber portion T1 on the XYθ drive mechanism moves directly below the upper chamber portion T2 and the upper chamber unit 6 is lowered, the flange of the upper chamber unit 6 is attached to the O-ring 12 arranged around the lower chamber unit 5. They come into contact with each other and function as a vacuum chamber. Here, the ball bearing 13 installed around the lower chamber unit 5 adjusts the amount of collapse of the O-ring 12 due to vacuum, and can be set at an arbitrary position in the vertical direction. The collapse amount of the O-ring 12 is set at a position where the inside of the vacuum chamber can be kept in a vacuum and the maximum elasticity is obtained. The large force generated by the vacuum is received by the lower chamber unit 5 via the ball bearing 13, and the lower chamber portion T1 is easily finely moved within the elastic range of the O-ring 12 when the upper and lower substrates to be described later are bonded together. You can decide.
[0015]
The housing 8 incorporates a vacuum seal that can move up and down without causing a vacuum leak to the shaft 9 even if the upper chamber unit 6 forms a vacuum chamber with the lower chamber unit 5 and deforms at atmospheric pressure. The force applied to the shaft 9 by the deformation of the vacuum chamber can be absorbed, the deformation of the pressure plate 7 supported by the shaft 9 can be substantially prevented, and the upper substrate 1b attached to the adhesive sheet 18 and the table 4 are held. Bonding is possible while maintaining parallel to the lower substrate 1a. The vertical movement of the pressure plate 7 is performed by a drive mechanism (not shown) installed at the upper part of the shaft 9.
[0016]
Reference numeral 14 denotes a vacuum pipe disposed on the side surface of the upper chamber unit 6, which is connected to a vacuum source by a vacuum valve and a pipe hose (not shown), and these are used when the inside of the vacuum chamber is depressurized and evacuated. A gas purge valve and a tube 15 are connected to a pressure source such as nitrogen gas (N2) or clean dry air, and these are used when the vacuum chamber is returned to atmospheric pressure.
[0017]
Next, the drive mechanism of the adhesive sheet 18 that holds the upper substrate 1b will be described.
17 in the upper chamber unit 6 is a spindle, and the adhesive sheet 18 wound in a roll shape can be driven and rotated in the delivery direction, freely rotated, and rotated and fixed in the delivery direction with a reverse torque applied to the delivery direction. It has become.
[0018]
The pressure-sensitive adhesive sheet 18 is directed to a rotation-free roller 20 on the opposite side via a rotation-free roller 19 and can be taken up by a spindle 21 that is positioned and fixed relative to the roller 20. The spindle 21 can drive and rotate the adhesive sheet 18 in the winding direction, and can be reversely rotated and fixed in a state where torque is applied in the winding direction. The take-up spindle 21 fixed in position relative to the roller 20 can be driven horizontally in the direction of the spindle 17 while driving and rotating the adhesive sheet 18 in the take-up direction. Since the pressure-sensitive adhesive surface of the pressure-sensitive adhesive sheet 18 is wound so as to be on the lower side, when the upper substrate 1b is attached to the pressure-sensitive adhesive sheet 18, it faces the lower substrate 1a.
[0019]
The rotation operation of the spindle 17 is performed by a motor 24 as shown in FIG. The rotating operation of the spindle 21 is performed by the motor 25, and the horizontal operation is realized by the ball nut 28 to which the motor 25 is fixed being rotated and moved by the ball screw 26 driven by the motor 27. The horizontal operation guide for the ball nut 28 is not shown. Reference numerals 29 and 30 denote support bearings of the ball screw 26. The support bearing 29 is fixed to the upper chamber unit 6. The support bearing 30 is fixed to the bracket 31 together with the shafts of the motor 24 and the roller 19, and the bracket 31 is fixed to the upper chamber unit. 6 is fixed to the structure.
[0020]
Reference numerals 22a and 22b denote image recognition cameras which are installed to read the alignment marks provided on the upper and lower substrates 1a and 1b. Reference numerals 23 a and 23 b are transparent viewing windows, and perform vacuum blocking of the holes 6 a and 6 b provided in the upper chamber unit 6.
[0021]
7a and 7b are small-diameter holes provided in the pressure plate 7 in order to see the alignment marks on the substrate. Here, the width of the adhesive sheet 18 is such that the adhesive sheet 18 does not block the visual field of the image recognition cameras 22a and 22b, as shown in FIG. It may be slightly smaller than the distance in the Y direction.
[0022]
Next, a process of bonding substrates with the substrate assembly apparatus 1 will be described with reference to FIGS.
FIG. 3A shows an initial state of the upper chamber portion T2 before the upper substrate 1b is held, and the spindle 21 is moved to the right side of the drawing with the adhesive sheet 18 spread, and the pressure plate 7 Is waiting upwards.
[0023]
FIG. 3B shows a state where the pressure plate 7 is lowered and brought into contact with the adhesive sheet 18 and then slightly lowered. At this time, the pressure-sensitive adhesive sheet 18 wound around the spindles 17 and 21 is fed out from both, but the pressure-sensitive adhesive sheet 18 performs torque control with the respective motors that rotationally drive the spindles 17 and 21, and is always subjected to a tensile force. Put it in a state. The pulling force is determined by the weight of the upper substrate 1b, and is set to such an amount that there is almost no gap between the upper plate 1b and the pressure plate 7 as shown in FIG.
[0024]
After the upper substrate 1b is stuck and held on the adhesive sheet 18 in this manner, the upper substrate 1b and the lower substrate 1a are bonded together as shown in FIG.
[0025]
First, as shown in FIG. 4 (a), the lower chamber portion T1 on which the lower substrate 1a is mounted on the table 4 is moved directly below the upper chamber portion T2, and as shown in FIG. The upper chamber unit 6 is lowered, the flange of the upper chamber unit 6 is brought into contact with the O-ring 12 arranged around the lower chamber unit 5, and the upper and lower chamber portions T 1 and T 2 are integrated, and then vacuum exhaust is performed from the vacuum pipe 14. Do.
[0026]
The lower substrate 1a is positioned and fixed on the table 4. On the outer periphery of the lower substrate 1a, a sealant is drawn in a closed pattern, and an appropriate amount of liquid crystal is dropped inside.
[0027]
When the inside of the vacuum chamber formed by integrating the upper chamber unit 6 and the lower chamber unit 5 reaches a predetermined degree of vacuum, the upper and lower substrates 1a and 1b are aligned as shown in FIG. While performing, a vertical drive mechanism (not shown) on the shaft 9 is operated, the pressure plate 7 is lowered, and the gap between the upper and lower substrates 1a and 1b is narrowed with a predetermined applied pressure, and bonded at a desired interval.
[0028]
At this time, as the pressure plate 7 is lowered, the adhesive sheet 18 wound around the spindles 17 and 21 is sent out from both. However, as described above, the adhesive sheet 18 is always in an appropriate tensile state, so The sheet 18 does not stretch or break. Further, the upper substrate 1b is substantially in close contact with the pressure plate 7 via the adhesive sheet 18 by this pulling force, and the central portion of the upper substrate 1b does not droop extremely, and the upper and lower substrates 1a and 1b are substantially parallel. Therefore, the central portion of the upper substrate 1b does not adversely affect the spacers scattered on the substrate 1a, and the alignment between the substrates is not impossible.
[0029]
Incidentally, the alignment between the substrates is performed by image processing by reading the alignment marks provided on the upper and lower substrates 1a and 1b with the image recognition cameras 22a and 22b from the observation windows 23a and 23b provided in the upper chamber unit 6. Is measured, and an XYθ drive mechanism (not shown) of the lower chamber portion T1 is finely moved to perform highly accurate alignment. In this fine movement, the ball bearing 13 maintains the space between the upper and lower chamber units 6 and 5 so that the vacuum is maintained without the O-ring 12 being extremely deformed.
[0030]
When the bonding is completed, a vacuum valve (not shown) connected to the vacuum pipe 14 is closed, the gas purge valve 15 is opened, N ₂ or clean dry air is supplied into the vacuum chamber, and the pressure is returned to atmospheric pressure. 15 is closed, and the process proceeds to a step of taking out the cell formed by the bonding shown in FIG.
[0031]
First, as shown in FIG. 5A, after the upper chamber unit 6 is raised by the cylinder 11, the pressure plate 7 is raised.
[0032]
Since the adhesive sheet 18 is adhered to the upper surface of the bonded upper substrate 1b, the operation of peeling the adhesive sheet 18 will be described below with reference to FIG.
[0033]
This operation is performed by rotating the spindle 21 and winding the adhesive sheet 18 and simultaneously moving it horizontally in the direction of the spindle 17 that is rotated and fixed at a speed synchronized with the winding speed.
[0034]
At this time, the pressure-sensitive adhesive sheet 18 is gradually peeled off from the upper surface of the upper substrate 1b, and when the spindle 21 is closest to the spindle 17, all of the pressure-sensitive adhesive sheet 18 is peeled off. is working.
[0035]
The bonded lower substrate 1a is sucked and adsorbed by the table 4, and does not shift or lift even while the adhesive sheet 18 is being peeled off.
[0036]
When the above operation is completed, as shown in FIG. 5B, the lower chamber portion T1 is moved to the left side of the drawing, the cell pc formed by attaching the upper and lower substrates 1b, 1a is removed from the table 4, and the spindle 17 is removed. In order to send out the new adhesive sheet 18, the spindle 21 is horizontally moved in the right direction while being rotationally fixed, and is prepared for the next bonding.
[0037]
Next, FIG. 6 demonstrates the board | substrate bonding in the board | substrate bonding apparatus which becomes other embodiment of this invention.
[0038]
In FIG. 6, the same reference numerals are given to the same or equivalent parts as those in the embodiment shown in FIGS.
[0039]
In this embodiment, instead of winding the adhesive sheet 18 by the spindle 21, a chuck mechanism 45 for the adhesive sheet 18 is provided, and the cutter 40 of the adhesive sheet 18 or the chuck of the adhesive sheet 18 is provided in the vicinity of the roller 19 on the spindle 17 side. A drive mechanism is provided.
[0040]
That is, in FIG. 6, the illustration of the upper substrate 1b is omitted for simplification, but after the substrates are bonded, the cutter base 43 supporting the cutter table 41 via the actuator 42 is replaced by the actuator 44 with the blade of the cutter 40. Raise to bottom position.
[0041]
Next, the cutter 40 is moved in the width direction (Y direction in the figure) of the adhesive sheet 18 at the outer periphery of the cell pc, and the adhesive sheet 18 to which the upper substrate 1b is attached is cut.
[0042]
The chuck 45 releases the adhesive sheet 18, takes out the cell pc with the adhesive sheet 18 attached, and peels off the adhesive sheet 18 from the cell pc at an appropriate time. Until the peeling, the adhesive sheet 18 functions as a protective film for the cell pc. If UV light is irradiated for curing the sealant, most of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet 18 is deteriorated by UV light, so that the pressure-sensitive adhesive sheet 18 can be easily peeled off at an appropriate time.
[0043]
After the cell pc is taken out, the cutter table 41 is slightly lowered by the actuator 42 to make a grip allowance for the chuck 45 at the end of the adhesive sheet 18. After the cutter 40 retracts (returns to the position shown in the figure), the ball screw 26 is rotated by driving the motor 27, and the chuck 45 goes to the roller 19 on the spindle 17 side to grip the end of the adhesive sheet 18. To do. A drive mechanism for gripping the adhesive sheet 18 in the chuck 45 is built in the chuck 45.
[0044]
Thereafter, the cutter base 43 is lowered by the actuator 44, the chuck 45 is moved to the right side of the drawing by the motor 27, the adhesive sheet 18 is fed out and kept horizontal, and is prepared for holding the next upper substrate 1b.
[0045]
Next, a first aspect of the present gun invention in FIG. 7, 2, illustrating the structure and the substrate bonding operation of a substrate laminating apparatus according to the embodiment corresponding to the 3.
[0046]
In FIG. 7, the same or equivalent parts as those in the embodiment shown in FIG. 1 to FIG.
[0047]
In FIG. 7, reference numeral 50 denotes an opening provided in the pressure plate 7, which is provided with an actuator 51 on the upper side, and an adhesive member 52 is provided on the tip of a shaft extending downward from the actuator 51. The adhesive member 52 moves up and down in the opening 50 by the operation of the actuator 51.
[0048]
The upper substrate 1b, with its adhesive applied to the lower surface of the adhesive member 52, is held in a form in close contact with the lower surface of the pressure plate 7. That is, the openings 50 are provided in the pressure plate 7 at appropriate intervals and positions according to the size and shape of the upper substrate 1b so that the upper substrate 1b can be held horizontally facing the lower substrate 1a. Yes.
[0049]
As shown in FIG. 7A, the lower chamber portion T1 in which the lower substrate 1a is fixed on the table 4 is moved below the upper chamber portion T2 that holds the upper substrate 1b with the adhesive member 52.
[0050]
Thereafter, as shown in FIG. 6B, the upper chamber unit 6 is lowered by the cylinder 11 to form a vacuum chamber with the lower chamber unit 5, and then the inside is depressurized and evacuated.
[0051]
Next, the upper and lower substrates 1b and 1a are aligned, the pressure plate 7 is lowered by the shaft 9, and the upper substrate 1b is pressed directly by the pressure plate 7 to bond the upper and lower substrates 1b and 1a. In this case, since the adhesive member 52 is provided in the opening 50, the applied pressure is applied equally to the upper substrate 1b.
[0052]
When the adhesive member 52 is peeled from the upper substrate 1 b of the cell pc formed by bonding, the adhesive member 52 is raised (retracted) in the opening 50 by the actuator 51. Then, since the peripheral part of the opening 50 of the pressure plate 7 prevents the upper substrate 1b from moving, the adhesive member 52 and the upper substrate 1b can be easily separated, and the pressure plate 7 serves as a means for removing the adhesive member 52. work.
[0053]
Thereafter, while purging the interior by supplying nitrogen gas N ₂ and clean dry air or the like in the vacuum chamber back to atmospheric pressure, to raise the upper chamber unit 6 raises the pressure plate 7, the figure lower chamber portion T1 After moving to the left side, the cell pc is taken out of the table 4.
[0054]
According to this embodiment, since the pressure-sensitive adhesive member is built in the pressure plate 7, the inside of the upper chamber unit 6 is simplified, the vacuum chamber can be reduced in size by reducing the size of the vacuum chamber, and the number of processed sheets can be increased. be able to.
[0055]
In addition, since the central portion that causes the sag of the upper substrate 1b can be lifted by the adhesive member built in the pressure plate 7, there is no concern that the central portion of the upper substrate will bend and damage the alignment film or the like.
[0056]
Not limited to the above embodiment, an adhesive member may be prepared in the table 4 and used for fixing the lower substrate 1a. Further, instead of the adhesive sheet 18, a plurality of adhesive tapes are installed along the two parallel sides of the upper substrate 1b as in the mechanism shown in FIGS. 1 and 2 so as to be movable in the upper chamber unit. Then, the upper substrate 1b may be held so as to be parallel to the lower substrate 1a.
[0057]
In any of the embodiments, since the upper substrate is held on the main surface side, the slack in the central portion can be eliminated, and even if the sealing agent is provided at the marginal portion of the substrate, the holding of the upper substrate is hindered. There is no.
[0058]
【The invention's effect】
As described above, according to the present invention, even when the substrate size is increased or thinned, the substrates can be bonded with high accuracy in a vacuum , and an adhesive is provided at the periphery of the substrate. Easily hold the upper substrate and bond without damaging the alignment film.
Moreover, the bonded substrates (cells) can be quickly and easily peeled off from the adhesive member that is the holding means.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a board assembly apparatus showing an embodiment of the present invention.
FIG. 2 is a perspective view of an adhesive sheet driving mechanism in the board assembly apparatus shown in FIG. 1;
3 is a cross-sectional view of a principal part showing an initial step of bonding upper and lower substrates in the substrate assembly apparatus shown in FIG. 1; FIG.
4 is a cross-sectional view of a main part showing a step of bonding both upper and lower substrates in the substrate assembly apparatus shown in FIG. 1;
5 is a cross-sectional view of a main part showing a step of taking out a cell formed by bonding both upper and lower substrates in the substrate assembly apparatus shown in FIG. 1;
FIG. 6 is a perspective view of an essential part showing a process of bonding upper and lower substrates in a substrate assembly apparatus according to another embodiment of the present invention.
FIG. 7 is a cross-sectional view of a main part showing a step of bonding upper and lower substrates in a substrate assembly apparatus according to still another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate assembly apparatus 1a Lower substrate 1b Upper substrate 4 Table 5 Lower chamber unit 6 Upper chamber unit 7 Pressure plate 12 O ring 13 Ball bearing 14 Vacuum piping 17, 21 Spindle 18 Adhesive sheet

Claims (3)

Held on the other substrate for bonding the one substrate bonding are opposed to each other, in the method of assembling a substrate bonding in a vacuum by an adhesive provided without Re of the substrate have,
One substrate is held by an adhesive means provided with a plurality of actuators incorporated in the pressure plate, and after being bonded to the other substrate, the adhesive means is retracted into the pressure plate, and the adhesive means wherein the gas peeling from the substrate, the assembly method of the substrate. The pressing plate for holding one substrate above the vacuum chamber, provided with a holding table for holding the other substrate beneath the vacuum chamber, provided on one of the substrate Izure was held at the pressurizing plate and the table in the assembly device for the substrate to align Ri adhered to substrates to each other by narrowing the distance between both substrates in a vacuum by an adhesive,
A plurality of actuators in said pressure plate, provided a shaft which expands and contracts in the actuator, the previously adhesive member above Kijiku provided, the adhesive lower surface thereof adhesive strength the pressure plate to the one substrate in the member A substrate assembling apparatus characterized in that the substrate is held in close contact with the lower surface of the substrate. The board assembly apparatus according to claim 2 , wherein
After laminating the one substrate held by the pressure plate and the other substrate held on the table by narrowing, the shaft is retracted into the pressure plate using the actuator. The substrate assembly apparatus is characterized in that the adhesive member is retracted into the pressure plate and the adhesive member is peeled off from the substrate surface.

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