WO2005041156A1

WO2005041156A1 - Method for sealing substrates while stacking

Info

Publication number: WO2005041156A1
Application number: PCT/JP2003/013536
Authority: WO
Inventors: Noriyuki Takefushi; Yasuyuki Koga; Hideki Oshima; Ryoichi Inaba
Original assignee: Shin-Etsu Engineering Co., Ltd.
Priority date: 2003-10-23
Filing date: 2003-10-23
Publication date: 2005-05-06
Also published as: CN100426338C; CN1692388A; KR20060093357A; KR100938192B1; JPWO2005041156A1; TW200517700A; JP3721378B2; AU2003275604A1; TWI266264B

Abstract

While interlocking with the operation of an electrostatic attraction means (5b) for releasing an upper substrate (A), gas (G) is jetted from the back side of the upper substrate and injected forcibly between the electrostatic attraction face (5b1) of an upper holding plate (1) and the back surface of the upper substrate. Since adhesion state of the electrostatic attraction face and the substrate surface is broken and they are stripped from each other, electrostatic attraction between them is attenuated forcibly and eliminated. Since a falling force or a falling acceleration acts forcibly on a lower substrate (B) due to the pressure of injected gas, the upper substrate adheres onto the lower substrate instantaneously. The upper substrate is moved, while being held by the electrostatic attraction means (5b), onto the lower substrate without varying the attitude, and bonded and stacked thereon while being sealed. The upper substrate can thereby be dropped forcibly while being aligned regardless of variation in the electrostatic attraction being released.

Description

Description Substrate overlay sealing method Technical field

In the present invention, for example, in the manufacturing process of a flat panel display such as a liquid crystal display (LCD) or a plasma display (PDP), two substrates used for the flat panel display are relatively aligned (aligned). The present invention also relates to a method of bonding and bonding substrates by a substrate bonding machine in which these substrates are laminated and sealed, and then a pressure difference between the two substrates is applied to a predetermined gap by a pressure difference between the inside and outside of the upper and lower substrates.

Specifically, the upper substrate is detachably held on the upper holding plate by electrostatic attraction means.

The lower substrate opposing the upper substrate is detachably held on the lower holding plate, and the upper and lower substrates are aligned with each other. The present invention relates to a substrate overlay sealing method for releasing the holding of an upper substrate and overlaying and sealing an upper substrate on a lower substrate. Background art

Conventionally, as this type of substrate overlapping sealing method, an electrostatic chucking method (electrostatic chucking function) in which a pressure plate is formed of an insulating member having an electrode plate embedded therein and which can hold an upper substrate (upper substrate) is used. After the upper substrate is held on the upper holding plate by the electrostatic suction means, and both substrates are aligned in the X and Y directions, the pressure in the vacuum chamber is reduced. Then, the electrostatic attraction function is released, the upper substrate is dropped onto the lower substrate, the upper and lower substrates are overlapped, and the upper and lower substrates are pressed by lowering the pressurizing plate. In some cases, the distance between the two is bonded to a predetermined gap (for example, see Patent Document 1). [Patent Document 1]

Japanese Patent Laid-Open Publication No. 2001-166662 2 (Page 6, Fig. 8)

However, in such a conventional substrate overlapping sealing method, the upper substrate is freely dropped in a vacuum by releasing the electrostatic attraction means, but the power of the substrate attraction by the electrostatic attraction means shuts off the power supply. Even though the substrate attraction force does not disappear immediately and continues to operate, uneven release occurs due to the subsequent decrease in substrate attraction force, and the interface between the electrostatic attraction surface and the upper substrate begins to peel off partially. Finally, the entire surface of the upper substrate is peeled off and falls freely.

As a result, the upper substrate is free-falling while rotating around the last peeled position, causing an error in the alignment between the two substrates and incomplete sealing under the free-fall pressure. Therefore, there is a problem that air is easily mixed.

Furthermore, the upper substrate is partially sagged by gravity from a portion where the upper substrate has begun to peel off first with respect to the electrostatic attraction surface, and the inclination is apt to change depending on the situation. However, it is difficult to correct even after falling on the lower substrate, and there is a problem that a predetermined parallelism cannot be achieved.

By the way, in recent years, the size of a substrate has been increasing, and one side of the substrate exceeds 1000 mm. However, even if the size of the substrate is increased, a parallelism similar to that of a small substrate is required. In particular, if one side of the substrate exceeds 1000 mm, the interval in the Z direction becomes extremely small compared to the size in the XY direction, so it is ideal to move the upper and lower substrates closer together while keeping them completely parallel. In practice it is very difficult.

In such an environment, if the large upper substrate whose one side exceeds 1000 mm is slightly inclined, the distance in the Z direction is extremely small compared to the size in the XY direction. Liquid crystal sealing material ( (Ring-adhesive) There is a risk of causing troubles such as damaging the film surface of both substrates, and there is a problem that normal bonding cannot be expected at all.

An object of the present invention described in claim 1 is to forcefully drop the upper substrate while being aligned regardless of the release unevenness of the electrostatic attraction force.

The invention described in claim 2 aims to completely prevent the displacement of the upper substrate due to uneven release of the electrostatic attraction force, in addition to the object of the invention described in claim 1.

The invention described in claim 3 has, in addition to the object of the invention described in claim 1 or 2, the upper substrate parallel to the lower substrate regardless of the electrostatic attraction surfaces of the upper and lower holding plates and the parallelism of the upper and lower substrates. It is intended to overlap. Disclosure of the invention

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention is characterized in that, in conjunction with the release of the holding of the upper substrate by the electrostatic adsorption means, gas is ejected from the back side of the upper substrate, By forcibly injecting this gas between the electrostatic attraction surface of the upper holding plate and the back surface of the upper substrate, the state of adhesion between the electrostatic attraction surface and the substrate surface is destroyed, and both are peeled off. The electrostatic attraction force is forcibly attenuated and disappears, and the pressure of the injected gas forcibly applies a drop force to the lower substrate, that is, a fall acceleration, whereby the upper substrate is The upper substrate is instantaneously pressed onto the lower substrate, moved to the lower substrate without any change in posture while being held by the electrostatic suction means, pressed and bonded, and the upper and lower substrates are sealed and overlapped .

Therefore, the upper substrate can be forcibly dropped while being aligned regardless of the release unevenness of the electrostatic attraction force.

As a result, the positioning error between the two substrates can be prevented and the sealing space can be secured, as compared with the conventional case where the upper substrate is freely dropped by releasing the electrostatic suction. To prevent mixing of air.

Furthermore, since no inclination occurs when the upper substrate is separated from the electrostatic attraction surface, a predetermined degree of parallelism can be achieved. Liquid crystal encapsulating sealing material (璟 -shaped adhesive) 障害 It can completely prevent obstacles such as damaging the film surface of the substrate.

The invention according to claim 2 is the same as the invention according to claim 1, except that in a state where the electrostatic chucking force still remains almost simultaneously or immediately after the holding of the upper substrate is released by the electrostatic chucking means. By starting ejection of gas from the back side of the upper substrate, the upper substrate is forcibly peeled off from the electrostatic attraction surface of the upper holding plate by gas pressure before uneven release of the electrostatic attraction force occurs.

Accordingly, it is possible to completely prevent the displacement of the upper substrate due to uneven release of the electrostatic attraction force.

The invention according to claim 3 has the structure of the invention according to claim 1 or 2, and further adjusts the amount, speed, and position of the gas ejected to the upper substrate according to a test result of a forced drop. By doing so, the attitude of the upper substrate that is forcibly dropped can be controlled.

Therefore, even if the electrostatic attraction surfaces of the upper and lower holding plates and the upper and lower substrates are not completely parallel, the upper substrate can be overlapped with the lower substrate in parallel. Brief Description of Drawings

FIG. 1 is a vertical cross-sectional front view of a substrate bonding apparatus directly used for carrying out a method of laminating and sealing substrates according to one embodiment of the present invention, wherein (a) shows a state after fine alignment of the substrates. (B) is a partially enlarged view showing a state before the upper substrate is forcibly separated from the electrostatic attraction surface, and (c) is a partially enlarged view showing the state after the peeling.

FIG. 2 is an explanatory diagram showing a state in which a substrate is set. FIG. 3 is an explanatory view showing a state in which the substrates are roughly aligned.

FIG. 4 is an explanatory diagram showing a state after bonding. BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIGS. 1 to 4, a substrate bonding apparatus directly used for carrying out the substrate laminating and sealing method of the present invention is relatively provided in the Z direction behind the upper holding plate 1 and the lower holding plate 2. A pair of upper and lower mounts 3, 4 movably arranged, and the upper and lower holding plates 1, 2 are enclosed between the mounts 3, 4 by approaching movement of the upper and lower mounts 3, 4. And a holding means 5 for detachably holding the upper substrate A and the lower substrate B provided in the upper holding plate 1 and the lower holding plate 2, respectively.

In this embodiment, the upper holding plate 1 is an upper surface plate 1 which is attached to a plate-like upper mounting body 3 movable in the (horizontal) direction so as to be movable only in the Z (vertical) direction. The plate 2 is a lower platen 2 integrally fixed on a plate-like lower mounting body 4, and the two glass substrates A and B held on the opposing surfaces of the upper platen 1 and the lower platen 2 This shows a case where coarse alignment and fine alignment are sequentially performed as alignment between the two substrates A and B by superimposing them in a vacuum closed space S1 and moving them relative to each other in the Χ Υ 6 »direction. It is.

The upper stool 1 and the lower stool 2 are configured as flat plates having a thickness that does not deform (radius) with a rigid body such as metal or ceramics. In the case of this embodiment, the upper stool 1 is mounted on the upper surface. The lower platen 2 is mounted and fixed on the central part of the lower mounting body 4 so as not to be deformed by deformation, and is supported by the lower edge plate 2 so as to be free from distortion deformation. The central part of the body 4 is connected to the frame base 14 to prevent further deformation.

In the case of the illustrated example, for example, a plurality of support beams 1 a continuously provided on the side surface of the upper stool 1 are loosely fitted into a plurality of lateral holes 3 b formed in the peripheral portion 3 a of the upper mounting body 3, respectively. In shape It is supported so that it can be adjusted and moved only in the Z direction by passing through it, and the space between the two is sealed with an elastic sealing material 1b such as a bellows.

Further, if necessary, a plurality of elastic members 1c such as springs, which can be elastically deformed only in the Z direction, from the upper mounting body 3 to the upper surface of the upper stool 1 may be provided.

In the illustrated example, the upper attachment body 3 is composed of a holding body formed in a flat plate shape, and a separable frame-shaped peripheral portion 3a that is airtightly connected to the periphery of the main body. These may be formed integrally.

In the case of this embodiment, the holding means 5 is provided with a suction source (not shown) such as a vacuum pump through a plurality of ventilation holes 5 al which are respectively formed in the opposing surfaces of the upper surface plate 1 and the lower surface plate 2. Suction and suction means 5a and 5a for sucking substrates A and B by suctioning, electrostatic suction means 5b and 5b for suction and holding in vacuum, and a substrate transfer robot (not shown) Delivery suction holding means 5c, 5c for receiving the upper and lower substrates A, B and transferring them to the substrate holding surfaces of the upper and lower stools 1, 2 are provided.

The suction source of the suction / suction means 5a, 5a and the power supply of the electrostatic suction means 5b, 5b are operated by a controller (not shown), and both substrates A, B are set. Suction suction and electrostatic suction are started in the initial state, and after the fine adjustment of both substrates A and B is completed, the suction suction and electrostatic suction of only the upper substrate A are released, and a closed space S1 described later is opened to the atmosphere. After returning to, the suction suction and the electrostatic suction of the lower substrate B are released to return to the initial state.

In the example shown in the figure, the electrostatic chucking means 5 b and 5 b are electrostatic chucks arranged close to each other and arranged in parallel, and are made of metal interposed between the opposing surfaces of the upper and lower platens 1 and 2. The electrostatic chuck is detachably connected to and fixed to the pedestals 5 d, 5 d of the suction chuck 5 d, 5 bl, 5 bl, which are the surfaces of the electrostatic chucks. a, 5 & vent holes 5 & 1, 5 al One has been established.

The delivery suction holding means 5 c, 5 c are penetrated movably in the Z direction across the pedestals 5 d, 5 d of the electrostatic chuck, the upper and lower bases 1, 2, and the upper and lower mounting bodies 3, 4. The lift bins, etc., are placed, and the substrate transfer robot (not shown) sucks and holds the substrates on the upper and lower platens 1 and 2 at a position that does not interfere with the non-matching surfaces of the upper and lower substrates A and B that are held by suction. They are transferred to the electrostatic chuck, which is a surface.

Further, if necessary, height adjusting jigs 1 d and 2 d, such as a counter panel, are interposed between the opposing surfaces of the upper and lower stools 1 and 2 and the pedestals 5 d and 5 d. The parallelism between the opposing surfaces of the pedestals 5 d, 5 d may be finely adjusted, or the pedestals 5 d, 5 d and the upper and lower platens 1, 2 without interposing the height adjustment jigs Id, 2 d. May be adhered.

The holding means for the substrates A and B is not limited to the above-described one. For example, if the vacuum is low, a vacuum suction means utilizing a vacuum difference is used instead of the electrostatic suction means 5b, 5b. You may.

Movement between the peripheral portion 3a of the upper mounting member 3 and the peripheral portion 4a of the lower mounting member 4 so as to be relatively movable in the X and Y directions while maintaining a sealed state therebetween. A sealing means 6 is provided in an annular shape so as to surround both the substrates A and B, and the closed space S 1 is moved between the upper and lower mounting bodies 3 and 4 by the approaching movement of the mounting bodies 3 and 4 so that the upper and lower platens 1 and 2 are closed. Is formed so as to be enclosed.

In the illustrated example, since the upper and lower substrates A and B are rectangular, the movable sealing means 6 is formed in a flat frame shape. However, the present invention is not limited to this. When A and B are circular, they are formed in similar shapes along their outer circumference.

In the case of the present embodiment, the moving seal means 6 includes a moving block 6 a having a rectangular or circular cross section in accordance with the planar shape of the upper and lower substrates A and B, For example, an annular seal material 6b that can be elastically deformed in the Z direction, such as a 0-ring, and an underside of the movable block 6a, for example, an O-ring that comes into contact with and separates from the peripheral edge 3a of the upper mounting body 3 mounted on the upper surface of the block 6a And an annular vacuum seal 6c such as an O-ring, which is always in contact with the peripheral portion 4a of the lower mounting member 4 and is movable in the XY0 direction.

For example, vacuum grease is used for this vacuum seal 6c as necessary.In the illustrated example, only one vacuum seal 6c is provided from the inner lower surface of the movable block 6a to the peripheral edge 4a of the lower mounting body 4. The interposed force is not limited to this, and although not shown, a vacuum seal 6c may be added to the outer lower surface of the moving block 6a to be double-interposed, similarly to the inner and outer annular sealing materials 6b. May be double interposed. Further, along one of the opposing surfaces of the substrates A and B, in this embodiment, along the peripheral edge of the surface of the lower substrate B, an annular adhesive C is previously closed as a sealing material for liquid crystal sealing. A liquid crystal (not shown) is filled in advance in the form of a frame, and a number of gap adjusting spacers (not shown) are scattered as needed.

Then, the above-described rough alignment is performed while maintaining the distance between the upper and lower substrates A and B so that the upper substrate A does not contact the annular adhesive C at all. The fine adjustment described above is performed in a state where the fine adjustment is made at least partially in the circumferential direction.

In order to perform these rough and fine adjustments, the board spacing adjusting means 7 for moving one or both of the upper and lower platens 1 and 2 in the Z direction with respect to the upper and lower mounting bodies 3 and 4 and the moving seal means 6 An engaging means 8 for engaging one of the upper and lower mounting bodies 3 and 4 in the XY 0 direction to integrate them, a horizontal moving means 9 for adjusting and moving the moving seal means 6 in the direction of Υ »6», Position adjustment means 10 having large rigidity in the vertical (Z) direction, which can move in the same direction as the upper and lower stool 1 and 2 move in the relative XY 6> direction, and the closed space S Top and bottom mounting body to open and close 1 Elevating means 11 for relatively elevating and lowering 3, 4 in the Z direction, and suction means 12 for taking in and out gas in the closed space S1 to attain a predetermined degree of vacuum are provided.

In the case of the present embodiment, a plurality of substrate spacing adjusting means 7 are provided at equal intervals in the circumferential direction on the upper surface of the moving block 6a toward the support beam 1a of the upper surface plate 1, which can be adjusted and moved in the Z direction. This is a driving body that expands and contracts in the Z direction, for example, a linear actuator, which is installed in the Z direction. It is performed sequentially.

The operation of the driving body of the board gap adjusting means 7 is controlled by a controller (not shown). Before setting both the boards A and B, the change factors such as the thickness balance of the boards A and B are considered. The upper and lower platens 1 and 2 are set in parallel by extending each driver separately, and the upper substrate A is placed on the lower substrate B when the closed space S1 is formed. Ring adhesive C and liquid crystal do not touch at all About l mn! A gap of about 2111111 is left, and then the two substrates A and B are successively shortened in conjunction with the rough and fine adjustments, so that the distance between the upper and lower substrates A and B is After the closed space S1 returns to the atmospheric pressure, it is extended and returned to the initial state by gradually approaching the space until the alignment accuracy can be sufficiently ensured by measurement. As a specific example, it is preferable that the upper substrate A is brought close to about 0.5 mm so that the upper substrate A does not come into contact with the annular adhesive C before the rough adjustment, and before the fine adjustment is performed. As a minimum value, the upper substrate A does not contact the lower substrate B even when the upper substrate A partially contacts at least a part of the circumferential direction of the circular adhesive C. The upper substrate A is further brought close to about 0.1 to 0.2 mm. Is preferred.

Although not shown, a driving body of the board gap adjusting means 7 may be provided from the peripheral portion 3 a of the upper mounting body 3 to the support beam 1 a of the upper stool 1.

In the case of the present embodiment, the engaging means 8 is, in the present embodiment, a concave portion 8a which fits only in the Z direction formed on a surface facing the moving block 6a of the moving sealing means 6 and the peripheral portion 3a of the upper mounting body 3. And the convex portion 8b. In the illustrated example, the concave portion 8a is moved. Although the moving block 6a of the dynamic sealing means 6 is recessed on the upper surface and the convex portion 8b is protruding on the lower surface of the peripheral portion 3a of the upper mounting member 3, they may be arranged upside down. In the present embodiment, the horizontal moving means 9 is provided at least outside the closed space S1.

A cam 9b connected to at least three motors 9a, and an elastic body 9c such as a spring, which constantly contacts the cam 9b with the moving work 6a. , B is operated by operating the camera 9a on the basis of the data output from a detector (not shown) composed of a microscope and a camera. And the upper mounting body 3 engaged with the upper board 3 is pushed in the direction, and the upper board A held on the upper stool 1 is roughly and finely aligned.

Is going.

The horizontal moving means 9 is not limited to the cam 9b connected to the motor 9a, but may be another driving source such as an actuator.

In the case of the present embodiment, the position adjusting means 10 is composed of a plurality of substantially parallel members extending in the Z direction. One end thereof is joined to each other, and the other end is moved by the moving sealing means 6. The workpiece 6a and the lower mounting body 4 are respectively joined to support a part of the plurality of members so that they can be bent and deformed only in the direction.

More specifically, a central member 10a having a large rigidity in the Z direction, the plurality of members being joined so as to hang from the lower surface of the moving block 6a toward the peripheral portion 4a of the lower mounting body 4, A peripheral member 1 Ob that is bent and deformed in the Θ Υ Θ direction and is joined to the lower surface of the peripheral portion 4 a of the lower attachment body 4 so as to surround the periphery thereof, and the central member 10 a and the peripheral member. And a connecting member 10c for joining and supporting the lower end of 1 Ob. By arranging a plurality of units in which these are integrated at predetermined intervals in the circumferential direction along the peripheral edge 4 a of the lower mounting body 4, the atmospheric pressure acting on the upper mounting body 3 ゃThe force such as the weight of the upper platen 1 is distributed to the respective central members 10a, which are vertically extended from the lower surface of the moving work 6a to the respective connecting members 10c, so that the respective central members 10a. a ... has Due to the large rigidity in the Z direction, the space between the lower surface of the moving block 6a and the peripheral edge 4a of the lower attachment 4 is maintained at a predetermined distance.

In particular, in the case of the illustration! J, the center member 10a is formed in a large-diameter cylindrical shape having high rigidity in the Z direction and not deforming in the Χ Θ direction. A through-hole 4b is movably penetrated in the XY 6> direction through the opened through-hole 4b, and a peripheral member 10b, which is formed of a link mechanism and is capable of being deformed in the 6-direction, is formed around the center member 10a. In addition to arranging a plurality of, for example, four, bending members 10d used at the lower end and upper end of these link mechanisms, for example, ball joints and the like, and connecting members 10c are formed into a flat disk shape. Has formed.

The structure of a plurality of members constituting the position adjusting means 10 is not limited to the illustrated one, and the peripheral member 1 Ob which can be deformed in the direction is elastically deformable in place of the link mechanism described above. Or an elastic rod composed of a plurality of elastically deformable column wires is arranged, and conversely, the rigidity of the surrounding member 1 Ob is increased in the Z direction to increase the rigidity in the X Υ Θ direction. Similar effects can be obtained with other structures, such as being formed to be undeformable and deforming the central member 10a in the »Υ 6Υ direction.

In the case of the present embodiment, the elevating means 11 is, for example, a jack or a vertical drive cylinder fixedly arranged from the periphery of the gantry 14 to the four corners of the peripheral edge 3 a of the upper attachment 3. The front end 11a is movably abutted against the peripheral portion 3a of the upper mounting body 3 and the intermediate block 1lb is moved by the moving block 6a of the moving sealing means 6 as shown in FIG. It is open so that it can move in one direction.

The operation of the drive source of the lifting / lowering means 11 is controlled by a controller (not shown). In an initial state in which the boards A and B are set, the upper mounting body 3 is raised to a predetermined height position, and the apparatus is on standby. After the setting of the boards A and B is completed, the upper mounting body 3 is lowered, and a closed space S1 is defined between the lower mounting body 4 and the lower mounting body 4 so as to surround the two substrates A and B. After the image formation and the fine adjustment of the two substrates A and B, or after the closed space S1, which will be described later, returns to the atmospheric pressure, it is raised to the initial state.

The suction means 12 is an air passage communicating with a vacuum pump (not shown) disposed outside the closed space S11. The operation of the vacuum pump is controlled by a controller (not shown). After the closed space S1 is formed by the approaching movement of the platens 1 and 2, air suction is started from the closed space S1, and in the case of the present embodiment, air is supplied to the closed space S1 after the operation of the substrate pressing means 13 described later. To return to atmospheric pressure.

In the case of the illustrated example, the air inlets 12a of the air passages are opened in the gaps formed between the opposing surfaces of the upper and lower stools 1 and 2 and the pedestals 5d and 5d, respectively. a, 1 2a adverse effects due to the air in closed space S1 flowing only in one direction from a, such as holding both substrates A and B tilting, and the liquid crystal previously filled on lower substrate B splashing out Has been prevented.

The substrate pressing means 13 forcibly pushes the upper substrate A electrostatically attracted to the electrostatic chuck, which is the substrate holding surface of the upper platen 1, toward the lower substrate B in the state after the fine alignment described above. As shown in Figs. 1 (b) and (c), when the electrostatic attraction of the upper substrate A by the electrostatic attraction means 5b is released, the electrostatic attraction force is almost simultaneously or immediately after. In the example shown in the drawing, the air chuck 5a, 5a, the air holes 5al, 5al are used to direct the electrostatic chuck from the electrostatic chuck toward the back side of the upper substrate A, for example, a gas G such as nitrogen gas or air. And the gas G is forcibly injected between the electrostatic attraction surface 5M of the upper holding plate 1 and the back surface of the upper substrate A, thereby destroying the close contact between the electrostatic attraction surface 5bl and the substrate surface. By peeling off both, the electrostatic attraction force between them was forcibly attenuated and disappeared, and injection was performed. The pressure of the gas G forces the drop force on the lower substrate B, that is, the acceleration of the drop, so that the upper substrate A is at least about 0.1 nm! Drop by about 0.2 mm and instantaneously press the entire circumference of the circular adhesive C on the lower substrate B. It should be noted that the injection of the above gas G was a little At least the following operating conditions must be set in advance.

(1) The delay time from when the electrostatic suction of the upper substrate A by the electrostatic suction means 5b is released to when the gas G is ejected.

(2) Injection pressure of gas G.

(3) Gas G injection time.

On the other hand, the substrates A and B are held by a substrate transport robot (not shown), transferred to the upper stool 1 and the lower stool 1 and delivered to the respective holding means 5, especially the upper substrate A In the case of, the film surface A2 is generally transported while holding only the peripheral portion so as not to be damaged because the film surface A2 faces downward. However, especially in the case of large substrates A and B, each side of which exceeds 1000 mm, holding only the peripheral portion described above causes the central portion of the film surface A 2 of the upper substrate A to hang down, and the film surface A 2 There is a possibility that the central portion may be damaged by hitting the foreign matter.

Therefore, in the case of this embodiment, as shown by the two-dot chain line in FIG. 2, a plurality of portions of the non-bonded surface (rear surface) A 1 on the opposite side to the ridge surface A 2 of the upper substrate A by the substrate transfer port. The central part of the film surface A2 is transported so as not to hang down, and the suction holding means 5c for transferring the holding means 5 to the non-bonding surface A1 of the upper substrate A is moved downward. It is stretched and sucked again at a position where it does not interfere with the suction position of the substrate transfer robot, and is transferred to the substrate holding surface of the upper stool 1.

Next, a method of sealing substrates by such a substrate bonding apparatus will be described in the order of steps.

First, the upper and lower substrates A and B are sucked and transferred by the substrate transfer robot and transferred to the holding means 5 of the upper stool 1 and the holding means 5 of the lower stool 1, respectively. The transfer robot suctions and transfers the non-bonded surface A1 of the upper substrate A, and, as shown by the two-dot chain line in FIG. By re-adsorbing, the non-bonded surface With the suction of only A1, the transfer from the substrate transport robot to the substrate holding surface of the upper platen 1 becomes possible, and the central part of the upper substrate A does not hang down as the substrates A and B become larger. .

As a result, even if the substrates A and B become large, they can be carried in without damaging the film surface A2.

In this manner, the upper substrate A and the lower substrate B, which was previously coated with an adhesive C and filled with liquid crystal, were pre-coated on the opposing surfaces of the upper stool 1 and the lower stool 2 as shown in FIG. When the substrates A and B are aligned and set, the substrates A and B are immovably sucked and held by the suction and suction means 5a and 5a and the electrostatic suction means 5b and 5b, respectively.

Then, as shown in FIG. 3, the upper mounting body 3 is lowered by the operation of the lifting / lowering means 11 to approach the lower mounting body 4, and the peripheral edge 3a of the upper mounting body 3 and the moving block 6a of the movable sealing means 6 are moved. The engagement means 8 respectively formed on the opposing surfaces of the movable block 6 are fitted only in the Z direction, and both are integrated in the XY 6 direction, and are closely contacted with the annular seal member 6 b on the movable block 6 a. A closed space S1 is formed between the upper and lower mounts 3 and 4 so as to surround the upper surface plate 1 and the lower surface plate 2 and both substrates A and B.

At the same time, the substrates A and B approach each other up to a predetermined interval due to the approach movement of the upper and lower stools 1 and 2, but the substrate interval adjusting means 7 reduces the distance to about l mn! The upper substrate A does not contact the circular adhesive C applied to the lower substrate B with a gap of about 2 mm, and the closed space S1 communicates between the substrates A and B. ing. Thereafter, the air is evacuated from the closed space S1 by the operation of the suction means 12 to a predetermined degree of vacuum, and the air is also evacuated from between the two substrates A and B to create a vacuum. As a result, atmospheric pressure acts on the upper and lower mounting bodies 3 and 4 surrounding the upper surface plate 1 and the lower surface plate 2, and the upper and lower mounting structures 3 and 4 can be deformed by a pressure difference from the vacuum closed space S1. However, atmospheric pressure does not act on the upper surface plate 1 in the closed space S 1 at all.

As a result, distortion of the upper surface plate 1 due to atmospheric pressure can be prevented without additional reinforcement Further, in the case of the present embodiment, the thickness of the lower mounting body 4 is increased to such a degree that the lower mounting body 4 does not deform even when atmospheric pressure acts, so that the lower surface plate 2 is not deformed under atmospheric pressure. .

In the case of the illustrated example, even if the upper mounting body 3 is deformed into the closed space S1 due to the atmospheric pressure, the elastic linking member 1 can be elastically deformed only in the Z direction over the upper surface of the upper surface plate 1. Due to c, there is an advantage that the distortion deformation of the upper mounting body 3 does not affect the upper surface plate 1 at all, and does not laterally shift in the XY 0 direction.

Then, in this vacuum state, as shown in FIG. 3, the upper platen 1 is lowered toward the lower platen 2 by the operation of the substrate gap adjusting means 7, and the distance between the upper and lower substrates A and B is reduced to about 0 at a minimum. After approaching to about 5 mm, the moving block 6 a of the moving sealing means 6 is pushed in the XY 0 direction by the operation of the horizontal adjusting means 9, and the moving block 6 a and the engaging means 8 are integrated. The upper mounting body 3 moves in the XY 0 direction relative to the lower mounting body 4, whereby the upper surface plate 1 moves relative to the lower surface plate 2 in the XY 0 direction, and both substrates A and B are connected to each other. Is roughly adjusted.

As a result, the two substrates Α and の in vacuum can be smoothly moved XY 0 from outside the closed space S1 without using the XY (stage), and rough adjustment can be performed with high accuracy.

At the same time, when the moving block 6a is pushed in the direction, the peripheral member 10b of the position adjusting means 10 bends and deforms, so that the central member 10a and the moving block 6a move in parallel. Due to the large rigidity in the vertical direction of the center member 10a, the atmospheric pressure acting on the upper mounting member 3 ゃ the lower surface of the movable block 6a while enduring the weight of the upper mounting member 3 and the upper surface plate 1, etc. The sliding resistance of the movable seal means 6 to the vacuum seal 6 c is reduced because the gap between the movable seal means 6 and the peripheral portion 4 a of the lower mounting body 4 is maintained at a predetermined interval.

As a result, the alignment between the two substrates A and B can be performed smoothly. Subsequently, as shown in FIGS. 1 (a) and 1 (b), the upper platen 1 descends toward the lower platen 2 by the operation of the substrate distance adjusting means 7, and the distance between the upper and lower substrates A and B is minimized. Small and about 0. L mn! After further approaching to about 0.2 mm, the upper platen 1 and the lower platen 2 are relatively adjusted and moved in the XY0 direction, and the two substrates A and B are finely aligned.

After this fine alignment is completed, the electrostatic attraction of the upper substrate A by the electrostatic attraction means 5b is completely released, and the substrate pressure bonding means 13 allows the plural air holes 5al and 5al to pass through, for example, nitrogen gas. The gas G is blown out evenly over the entire non-bonded surface (back surface) A 1 of the upper substrate A, and the gas G is discharged between the electrostatic adsorption surface 5 bl of the upper holding plate 1 and the rear surface of the upper substrate A. By forcibly injecting, the adhesion between the electrostatic adsorption surface 5bl and the substrate surface is broken, and the two are peeled off, so that the electrostatic adsorption force between the two is forcibly attenuated and disappears, and the injection is performed. The force of the gas G, which is forced to fall on the lower substrate B, that is, the acceleration of the drop, forces the upper substrate A onto the lower substrate B instantaneously as shown in FIG. 1 (c). The ring-shaped adhesive C is sealed by pressure bonding over the entire circumference, so that a sealed space S2 is reliably formed.

As a result, even if the power supply of the electrostatic attraction means 5b is cut off, even if the substrate attraction force does not disappear and continues to function even after the power supply to the electrostatic attraction means 5b has been stopped, it is not affected by the release unevenness of the substrate attraction force. The upper substrate A can be forcibly dropped while aligned in the XY 0 direction.

Thereby, there is an advantage that an alignment error between the two substrates A and B can be prevented, and the sealing space S2 can be reliably formed, thereby preventing air from being mixed. Further, when the gas G is ejected from the back side of the upper substrate A almost simultaneously with or immediately after the holding of the upper substrate A by the electrostatic suction means 5 b is released, the electrostatic adsorption force is released. Before the unevenness occurs, the upper substrate A is forcibly peeled off from the electrostatic attraction surface 5 bl of the upper holding plate 1 by the gas G pressure.

As a result, the displacement of the upper substrate A due to uneven release of the electrostatic attraction force is completely prevented. There is an advantage that it can be stopped.

In this case, if the amount, the ejection speed and the ejection position of the gas G to the upper substrate A can be adjusted, the ejection of the gas G to the upper substrate A depends on the test result of forcibly dropping. By adjusting the amount, the ejection speed and the ejection position, the posture of the upper substrate A that is forcibly dropped can be controlled.

As a result, there is an advantage that the upper substrate A can be overlapped with the lower substrate B in parallel even if the electrostatic attraction surfaces 5 bl of the upper and lower holding plates 1 and 2 and the upper and lower substrates A and B are not completely parallel. is there.

Then, after the press-bonding of both substrates A and B is completed, air or nitrogen is put into the closed space S1 by the operation of the suction means 12 to return the atmosphere to the atmospheric pressure.

Thus, the substrates A and B are evenly crushed by a pressure difference between the inside and outside of the substrates, and a predetermined gap is formed in a state where the liquid crystal is sealed.

Thereafter, when the inside of the closed space S 1 returns to the atmospheric pressure, the upper mounting body 3 and the upper stool 1 and the lower mounting body 4 and the lower stool 2 are separated by the operation of the lifting / lowering means 1 1 to close the closed space.

S1 is released, the aligned substrates A and B are taken out by the substrate transfer robot, and the above-described operation is repeated.

In the embodiment shown above, the upper mounting body 3 is placed behind the upper surface plate, which is the upper holding plate 1.

The lower mounting body 4 is integrally fixed behind the lower holding plate 2 serving as the lower holding plate 2 so as to be movable in the Z direction, but is not limited thereto. By disposing the lower mounting member 4 separately from the lower mounting member 4, even if the lower mounting member 4 is deformed by atmospheric pressure, the lower mounting plate 2 may not be affected.

In this case, the same as the elastic member 1c such as a spring, which is elastically deformable only in the Z direction and is connected between the upper mounting body 3 and the upper surface of the upper platen 1 as necessary, and is elastically deformable, for example, It may be arranged between the board and the lower mounting body 4 so that both are connected. Industrial applicability

As described above, the substrate overlapping sealing method according to the present invention is used in the industry of manufacturing flat panel displays such as liquid crystal displays (LCD) and plasma displays (PDP).

Claims

The scope of the claims

1. The upper substrate (A) is detachably held on the upper holding plate (1) by the electrostatic suction means (5b), and the lower substrate (B) opposed to the upper substrate (A) is held on the lower holding plate (5). 2) The upper and lower substrates (A, B) are removably held on top of each other, and the upper and lower substrates (A, B) are aligned with each other. (A) is released, and the upper substrate (A) is overlaid and sealed on the lower substrate (B).

In conjunction with the release of the holding of the upper substrate (A) by the electrostatic suction means (5b), gas (G) is ejected from the back side of the upper substrate (A), and the upper holding plate is pressed by the gas (G) pressure. Substrate stacking characterized by forcibly peeling off the upper substrate (A) from the electrostatic attraction surface (5bl) of (1), and pressing and sealing onto the lower substrate (B) instantaneously. Match sealing method.

2. At the same time or immediately after the holding of the upper substrate (A) by the electrostatic suction means (5b) is released, or immediately after, the electrostatic suction force remains, from the back side of the upper substrate (A). 2. The method according to claim 1, wherein the ejection of the gas (G) is started.

3. The method according to claim 1, wherein an amount, an ejection speed, and an ejection position of the gas (G) to the upper substrate (A) are adjustable.