JP4043506B1 - Work transfer method, electrostatic chuck apparatus, and substrate bonding method - Google Patents

Abstract

Even a thin and low-rigid workpiece is placed open without any deformation or misalignment during movement.
The electrostatic chuck (2) is attached to the holding plate (1) by the attaching means (3), and the workpiece (A) is attracted and held by the attached electrostatic chuck (2), and the electrostatic chuck (2). And the workpiece (A) are separated from the holding plate (1) by the separating means (4) as a unit, so that the workpiece (A) does not become free, so that it is transferred to the open position without being affected by gravity or the like. At the same time, after the electrostatic chucking function of the electrostatic chuck (2) is stopped, only the electrostatic chuck (2) is reattached to the holding plate (1) by the attaching means (3), thereby moving to the open position. The electrostatic chuck (2) is peeled off from the surface of the workpiece (A), and the workpiece (A) remains in the open position and is placed.
[Selection] Figure 1

Description

The present invention relates to a glass substrate such as CF glass or TFT glass or PES (Poly-Ether-Sulphone) in the manufacturing process of a flat panel display such as a liquid crystal display (LCD), a plasma display (PDP), and a flexible display. Substrate assembling apparatus including a substrate laminating machine that detachably holds a synthetic resin substrate made of plastic film or the like, and a work such as an insulator such as a substrate, a conductor or a semiconductor wafer (processed) The present invention relates to a workpiece transfer method and an electrostatic chuck device used in a substrate transfer device for transferring a body, and a substrate bonding method using the same.
Specifically, the method includes a workpiece transfer method in which a workpiece is sucked and held by an electrostatic chuck of a holding plate, the held workpiece is released and placed at a predetermined position, and a holding plate and an electrostatic chuck that holds the workpiece by suction. The present invention relates to an electrostatic chuck device and a substrate bonding method using the same.

Conventionally, as a substrate laminating machine for superimposing two substrates, the pressure plate is an electrostatic chuck composed of an insulating member with an electrode plate built in, and a glass substrate is held as a workpiece on top of this. After aligning the substrate and the lower substrate in the X and Y directions, the vacuum chamber is depressurized, and when the vacuum chamber reaches a desired degree of vacuum, the electrostatic chucking function of the pressure plate is released, and the upper substrate is Some are dropped on the lower substrate to overlap the upper and lower substrates, and then the pressure plate is lowered to press the upper and lower substrates so that the distance between them is bonded to a predetermined gap (for example, see Patent Document 1). .
In conjunction with the release of the upper substrate (upper substrate) by the electrostatic chuck (electrostatic chucking means), gas is ejected from the back side of the upper substrate, and this gas is discharged from the electrostatic chucking surface of the upper holding plate. By forcibly injecting between the back surface of the upper substrate, the adhesion state between the electrostatic adsorption surface and the substrate surface is destroyed and the both are peeled off, so that the electrostatic adsorption force between them is forcibly attenuated and disappears. At the same time, the drop force to the lower substrate (lower substrate), that is, the acceleration of the drop, is forcibly applied by the pressure of the injected gas, whereby the upper substrate is instantaneously pressed onto the lower substrate, In some cases, the upper substrate is moved and pressed onto the lower substrate without changing its posture while being held by the electroadsorption means, and the upper and lower substrates are sealed and overlapped (for example, see Patent Document 2).

JP 2001-166272 A (page 6, FIG. 8) Japanese Patent No. 3721378 (page 8, FIG. 1)

However, in such a conventional workpiece transfer method and electrostatic chuck apparatus, in the case of Patent Document 1, the workpiece (upper substrate) is freely dropped in vacuum by releasing the electrostatic adsorption function. Even if the power supply to the substrate is shut off, the substrate suction force does not disappear immediately, and continues to act. Begins to peel partially, and finally the entire surface of the workpiece peels and falls freely.
As a result, the workpiece (upper substrate) falls freely while rotating around the last peeled position, causing an error in alignment between the upper and lower substrates, and incomplete sealing with free fall pressure As a result, there was a problem that air was easily mixed.
In addition, the workpiece (upper substrate) partly hangs down due to gravity from the point where it first began to peel off from the electrostatic chuck surface, and this tilt is easy to change depending on the situation. In addition to being impossible to correct during dropping, 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, substrates of liquid crystal displays and plasma displays have started to be manufactured up to a size exceeding 1000 mm on a side, but parallelism similar to that of a small substrate is required even if the substrate is enlarged. In particular, if one side of the substrate exceeds 1000 mm, the distance in the Z direction is extremely small compared to the size in the XY direction. It is very difficult.
In such an environment, if a large upper substrate with a side exceeding 1000 mm is tilted even slightly, the distance in the Z direction is extremely small compared to the size in the XY direction. There is a risk that damage such as damage to the sealing material for sealing liquid crystal (annular adhesive) applied in advance or the film surfaces of both substrates may occur, and there is a problem that normal bonding cannot be expected.
In the case of Patent Document 2, gas is jetted from the back side of the work (upper substrate) to the work to separate it, but it is 0.7 to 1.1 mm like a conventionally used work. In the case of a glass substrate having a thickness of 1.5 mm, since the rigidity in the surface direction is relatively high, the peeling gas is easily transmitted uniformly in the surface direction, and the gas can be reliably peeled off from the electrostatic chuck.
By the way, in recent years, there are many uses for liquid crystal displays that place emphasis on weight reduction, such as mobile phones and laptop computers. In such applications, the glass thickness of the workpiece is about 0.5 mm or less. Furthermore, the workpiece used for the flexible display is a plastic film such as PES (Poly-Ether-Sulphone) having a thickness of several hundreds of um.
Since a workpiece such as a glass substrate or a plastic film of about 0.5 mm or less is extremely low in rigidity compared to a conventionally used glass substrate of 0.7 to 1.1 mm, a gas for peeling is used. Even if the jet is ejected, the workpiece is partly extruded and deformed, and the flow path of the peeling gas concentrates on the deformed portion, and there is a possibility that the workpiece cannot be reliably peeled by the residual adsorption force. At the time of peeling, there is a possibility that the portion that is being deformed by the peeling air current is stretched intensively and a partial distortion remains.

Among the present inventions, the first and fourth aspects of the present invention are intended to open and mount even a thin and low-rigid workpiece without causing deformation or misalignment during movement.
In addition to the object of the invention described in claim 1, the invention described in claim 2 is intended to reliably hold and transfer the workpiece.
The invention described in claim 3 aims to improve the peelability of the workpiece in addition to the object of the invention described in claim 2 .
In addition to the object of the invention described in claim 4, the invention described in claim 5 can be securely bonded and peeled off at a fixed position regardless of unevenness in releasing the electrostatic adsorption force even if the substrate has low rigidity. It is aimed at.

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention is characterized in that an attaching means for pulling an electrostatic chuck to the holding plate so as to be detachable along the holding plate, and an electrostatic device from the holding plate. And an isolating means for separating the chuck, the electrostatic chuck is attached to the holding plate by the attaching means, the work is attracted and held by the attached electrostatic chuck, and the electrostatic chuck and the work are integrated with the isolating means. After the electrostatic chuck function of the electrostatic chuck was stopped by separating the electrostatic chuck from the holding plate, only the electrostatic chuck was reattached to the holding plate by the attaching means so that the workpiece was placed on the open position. It is characterized by this.
According to a second aspect of the present invention, in the configuration of the first aspect of the invention, the electrostatic chuck is formed in a thin plate shape or a film shape, and in a direction intersecting with a smooth base surface of a holding plate made of a rigid body. It is characterized by the addition of a movable support structure.
According to a third aspect of the invention, in the configuration of the second aspect of the invention, when only the electrostatic chuck is reattached to the holding plate by the attaching means, the outer periphery of the workpiece of the electrostatic chucking portion of the electrostatic chuck The electrostatic chuck is forcibly separated from the workpiece between the electrostatic chucking portion of the electrostatic chuck and the outer peripheral end of the workpiece by first drawing the portion facing the end portion and partially deforming it. For this reason, a configuration in which a gap for forming a part is formed is added.
According to a fourth aspect of the present invention, there is provided an electrostatic chuck for electrostatically attracting a workpiece, a holding plate for holding the workpiece via the electrostatic chuck, and the electrostatic chuck being detachably bonded to the holding plate. and attachment means, and isolation means for isolating said electrostatic chucking click from the holding plate, the sequestered electrostatic chuck with and a said attachment means or suction attracting means placed along attract to the holding plate, the electrostatic An operation means for stopping the electrostatic attraction function of the chuck and operating the isolation means and the adhering means or the suction adsorbing means is provided. In the state of being bonded to the holding plate, the separating means is operated to move the workpiece together with the electrostatic chuck to the workpiece transfer position, and then the electrostatic chucking function of the electrostatic chuck is stopped. Thereafter, the attachment means or suction by operating the suction means, characterized in that adhering to the holding plate by the attachment means peel off the electrostatic chuck from the workpiece.
A fifth aspect of the present invention is a substrate bonding method for bonding a pair of substrates using the electrostatic chuck device according to the fourth aspect, wherein one of the pair of substrates is opposed to the other, and the static The electrostatic chuck device is detachably held on the holding plate via the electrostatic chuck, and the electrostatic chuck is pulled away from the holding plate while the one substrate is electrostatically attracted, and the substrate is separated from the other substrate. The two substrates are bonded together with an annular adhesive.

According to the first aspect of the present invention, the electrostatic chuck is attached to the holding plate by the attaching means, and the work is attracted and held by the attached electrostatic chuck, and the electrostatic chuck and the work are separated as a unit. By separating from the holding plate by means, the workpiece does not become free, so it is transferred to the open position without being affected by gravity, etc., and the electrostatic chuck function of this electrostatic chuck is stopped and then attached By reattaching only the electrostatic chuck to the holding plate by means, the electrostatic chuck is peeled off from the surface of the work moved to the open position, and the work remains and is placed on the open position.
Therefore, even a thin and low-rigidity workpiece can be placed open without causing deformation or misalignment during movement.
As a result, it is possible to transfer the workpiece to a fixed position while maintaining the posture of the workpiece in a stable manner as compared with the conventional device in which the posture of the workpiece is likely to become unstable due to the occurrence of unevenness of the electrostatic attraction force due to the release of the electrostatic adsorption.
Furthermore, compared to the conventional type that peels the workpiece with the gas injection pressure, the flow path of the peeling gas does not concentrate on a specific part even for a workpiece with low rigidity, and it can be peeled off in the same way as a workpiece with high rigidity. It is excellent in workability.

In addition to the effect of the invention of claim 1, the invention of claim 2 forms the electrostatic chuck in a thin plate shape or a film shape, and moves in a direction crossing the smooth base surface of the rigid holding plate. By freely operating and adhering means, flattening at least the electrostatic chucking part of the electrostatic chuck along a smooth base surface made of a rigid body, the base surface and the electrostatic chucking part have no gap. Contact is electrostatically attracted, and then the workpiece is not freed by separating the electrostatic chuck from the base surface while the workpiece is electrostatically attracted by the operation of the separating means, so it is not affected by gravity, etc. Thereafter, the electrostatic chuck is peeled off from the surface of the moved workpiece by the operation of the attaching means, and returned to the initial state along the base surface.
Accordingly, the workpiece can be reliably held and transferred.

According to a third aspect of the present invention, in addition to the effect of the second aspect of the invention, the electrostatic chucking portion of the electrostatic chuck is partially deformed from a position facing the outer peripheral end portion of the workpiece, and the outer peripheral end of the workpiece is By partially forming a separation gap between the electrostatic chuck and the part, the separation gap spreads between the electrostatic chuck part of the electrostatic chuck and the surface of the workpiece at once, and the residual suction force is forced. Attenuates and disappears.
Therefore, the peelability of the workpiece can be improved.

According to the invention of claim 4, the electrostatic chuck is movably supported in a direction intersecting with the workpiece side surface of the holding plate, and the workpiece surface is placed with the electrostatic chuck along the workpiece side surface. By electrostatically attracting and moving the electrostatic chuck from this attracting position while the workpiece is electrostatically attracted, the workpiece is not brought into a free state, so that it is transferred to the open position without being affected by gravity or the like. At the same time, the electrostatic chuck function of the electrostatic chuck is stopped, and only the electrostatic chuck is reversely moved from the open position toward the chuck position, whereby the electrostatic chuck is peeled off from the surface of the workpiece moved to the open position.
Therefore, even a thin and low-rigidity workpiece can be placed open without causing deformation or misalignment during movement.
As a result, it is possible to transfer the workpiece to a fixed position while maintaining the posture of the workpiece in a stable manner as compared with the conventional device in which the posture of the workpiece is likely to become unstable due to the occurrence of unevenness of the electrostatic attraction force due to the release of the electrostatic adsorption.
Furthermore, compared to the conventional type that peels the workpiece with the gas injection pressure, the flow path of the peeling gas does not concentrate on a specific part even for a workpiece with low rigidity, and it can be peeled off in the same way as a workpiece with high rigidity. It is excellent in workability.

In addition to the effect of the invention of claim 4, the invention of claim 5 moves the electrostatic chuck away from one of the holding plates while the one substrate is electrostatically attracted, and moves toward the other substrate. By sticking both substrates together with a ring adhesive, one substrate does not become free, so it is transported and bonded accurately without being affected by gravity, etc., and held with the adhesive force of the ring adhesive. The electrostatic chuck peels off from one substrate without difficulty.
Therefore, even if the substrate has low rigidity, it can be securely bonded and peeled off at a fixed position regardless of the uneven release of the electrostatic adsorption force.
As a result, compared to conventional substrate laminating machines that allow the upper substrate to fall freely by releasing electrostatic attraction, it is possible to prevent misalignment between the two substrates and to reliably form a sealed space and prevent air contamination. In addition, since there is no tilt at all with the peeling of the upper substrate from the electrostatic chucking surface, the specified parallelism can be achieved, and even if it is a large substrate with one side exceeding 1000 mm, it is caused by the tilt of the upper substrate. It is possible to completely prevent troubles such as damage to the sealing material for sealing liquid crystal (annular adhesive) and the film surfaces of both substrates.
Furthermore, compared to conventional substrate laminating machines that directly peel off only the substrate with the gas injection pressure, the flow path of the peeling gas does not concentrate on a specific part even if the substrate is low in rigidity. Can be reliably peeled off and has excellent workability.
In addition, even if the surface of the electrostatic chuck is partially broken due to a foreign object being caught, the holding plate and the thin or film-like electrostatic chuck are separate parts. Since the electric chuck can be easily replaced, it is easy to maintain. Especially when the electrostatic chuck device of the present invention is used in a production line such as a liquid crystal display, the operation of the entire line can be resumed in a short time. Will not decrease, and stable production can be expected.

  The workpiece transfer method and electrostatic chuck apparatus D of the present invention detachably hold a glass substrate or a plastic film substrate used for a liquid crystal display (LCD), a plasma display (PDP) or a flexible display panel as the workpieces A and B. This shows the case where it is deployed in a substrate laminating machine.

  As shown in FIGS. 5A to 5C, this substrate laminating machine is composed of a pair of upper and lower plates made of a platen having a thickness that does not deform (bend) with a rigid body such as metal or ceramics. The holding plates 1 and 1 'are arranged, and the two substrates A and B are detachably held on the parallel and opposing smooth surfaces of the upper and lower holding plates 1 and 1', respectively, and are partitioned around them. After the inside of the vacuum chamber S reaches a predetermined degree of vacuum, the upper and lower holding plates 1, 1 ′ are moved relative to each other in the XYθ direction (horizontal direction in the drawing) to align the substrates A and B with each other. Thereafter, at least one of the substrates A and B is peeled off from the smooth surfaces of the upper and lower holding plates 1 and 1 ′ and superposed, and then the vacuum in the vacuum chamber S is broken, so that both the substrates A and B are placed inside and outside. The pressure difference between the two substrates A and B is pressurized to a predetermined gap.

  More specifically, as shown by the solid line in FIG. 5 (a), the upper and lower holding plates 1 and 1 'are supported by an elevating means (not shown) so as to be relatively movable in the Z direction (vertical direction in the drawing). In an atmosphere of atmospheric pressure, the substrates A and B transferred by a transfer robot (not shown) are set and held on the respective smooth surfaces with the upper and lower holding plates 1 and 1 'separated in the vertical direction. Is done.

Thereafter, as shown by the two-dot chain line in FIG. 5A, the upper and lower holding plates 1 and 1 'are moved closer to each other by the operation of the elevating means, and a vacuum chamber S is formed between them.
Subsequently, when the air is exhausted from the vacuum chamber S by the operation of the suction means (not shown) to reach a predetermined degree of vacuum, the upper and lower holding plates 1 are operated by the operation of the horizontal movement means (not shown). , 1 ′ is adjusted and moved in the XYθ direction with respect to the other, so that rough alignment and fine alignment are sequentially performed as alignment between the substrates A and B held by them.

  After these alignments are completed, as shown in FIG. 5B, one of the substrates A and B held by the upper and lower holding plates 1 and 1 'is moved toward the other, and the upper substrate B By sandwiching the annular adhesive (sealing material) C, the two are sealed and overlapped.

  Thereafter, as shown in FIG. 5 (c), the upper and lower holding plates 1, 1 'are moved away from each other by the operation of the elevating means, and the intake means is reversely operated substantially simultaneously with this, or another mechanism is provided. By supplying air or nitrogen into the vacuum chamber S and returning the atmosphere in the vacuum chamber S to atmospheric pressure, the pressure is evenly pressurized by the pressure difference generated inside and outside the substrates A and B, and the liquid crystal is enclosed. In this state, the bonding process is completed by crushing to a predetermined gap.

And the electrostatic chuck apparatus D of this invention is comprised by the upper and lower holding plates 1 and 1 'which consist of a rigid body mentioned above, and the electrostatic chuck 2 which adsorbs-holds the board | substrates A and B. FIG.
In the illustrated example, the electrostatic chuck 2 is supported so as to be movable in the Z direction (vertical direction in the drawing) intersecting with the smooth surface of the upper holding plate 1. An attaching means 3 for pulling 2 toward each smooth surface and detachably adhering thereto, and an isolating means 4 for separating the electrostatic chuck 2 from each smooth surface are provided.

  The attaching means 3 attaches the electrostatic chuck 2 to the smooth surface of the upper holding plate 1, and electrostatically attracts the upper substrate A with the attached electrostatic chuck 2, and the electrostatic chuck 2 and the upper substrate A Are separated from the upper holding plate 1 toward the open position by the separating means 4 and moved in parallel, and the electrostatic chucking function of the electrostatic chuck 2 is stopped. Thereafter, only the electrostatic chuck 2 is attached by the attaching means 3. When the electrostatic chuck 2 is peeled off from the surface of the upper substrate A moved to the open position by moving backward from the open position toward the upper holding plate 1, the above-described bonding operation of the substrates A and B is performed. .

  The electrostatic chuck 2 includes, for example, a dielectric 2b formed in a smooth thin plate or thin film with an insulating organic material such as polyimide, polyetheretherketone (PEEK), polyethylene naphthalate (PEN), and the like. An electrode portion 2c made of conductive paste or conductive foil patterned by screen printing or the like is integrally laminated.

The electrode portion 2c is formed insulated from the surroundings and connected to a power source (not shown) for applying a voltage thereto.
As a specific example, it is preferable to use a bipolar electrostatic chuck in which two or more electrode portions 2c are embedded in, for example, a comb shape.
Further, the electrode portion 2c of the electrostatic chuck 2 that is supported so as to be reciprocally movable in the vertical direction is controlled so that the power supply connection is cut immediately after the operation of the separating means 4 to be described later is terminated and the electrostatic adsorption function is stopped. Has been.

  The attachment means 3 includes, for example, a magnet 3a such as a permanent magnet or an electromagnet over one or both of the smooth surfaces of the upper and lower holding plates 1 and 1 'and the surface of the electrostatic chuck 2 facing the upper and lower holding plates 1 and 1'. Either a magnet to be attracted or a magnetic material 3b such as a metal formed into a film by sputtering or the like is fixedly arranged, or an adhesive material other than magnetic force or a structure other than a mechanical one-touch connection mechanism is fixedly arranged. Thus, the electrostatic chuck 2 is detachably bonded to the smooth surface by the magnetic force or the adhesive force.

The separating means 4 injects a gas such as nitrogen gas or air or other fluid from one or both of the smooth surfaces of the upper and lower holding plates 1 and 1 ′ toward the opposite surface of the electrostatic chuck 2, for example. 2, or the electrostatic chuck 2 is pressed with a driving body such as an air cylinder that reciprocates up and down, or one of the magnetic poles of the magnets 3 a and 3 b provided in an opposing manner as the attachment means 3. By converting and repelling the magnetic poles of the opposing magnets 3a and 3b to be the same, the electrostatic chuck 2 is separated from the smooth surface in parallel.
Embodiments of the present invention will be described below with reference to the drawings.

  In Example 1, as shown in FIGS. 1A and 1B, a base (base) made of a rigid body in which the magnet 3a of the attachment means 3 is embedded is projected on the smooth surface of the holding plate 1, A thin plate or thin film electrostatic chuck 2 in which the magnet 3b of the attaching means 3 is laminated is reciprocated in the vertical direction by a guide means (not shown) with respect to the smooth base surface 1a of the tip surface. As the separating means 4, a gas or a fluid is jetted toward the electrostatic chuck 2 from the vent hole 4 a provided in the holding plate 1 and the pedestal, or the base surface 1 a is electrostatically By increasing the internal pressure of the sealed space 4b formed between the chuck 2 and the chuck 2, the entire electrostatic chuck 2 is separated from the base surface 1a in parallel against the magnetic force of the attaching means 3. This shows the case.

  The holding plate 1 and the pedestal are provided with suction suction means 5 for sucking and holding in the atmosphere, and a plurality of suction paths formed as the suction suction means 5 are, for example, suction sources (not shown) such as a vacuum pump. And the suction passage is used as the vent hole 4a of the separating means 4.

  In the drawing, the electrostatic chuck 2 is supported on the smooth surface of the upper holding plate 1 so as to be reciprocable in the vertical direction, so that the rigidity of the workpiece A is about 0.5 mm or less and the upper substrate is extremely low. Although only the example of moving while holding the surface by suction is shown, the surface of the lower substrate B is supported by supporting the electrostatic chuck 2 so as to reciprocate up and down with respect to the smooth surface of the lower holding plate 1 ′. The same applies to the case of moving while adsorbing and holding.

  As the magnet 3a fixedly arranged on the pedestal of the holding plate 1, a permanent magnet or an electromagnet is used, and as the magnet 3b fixedly arranged on the opposing surface of the electrostatic chuck 2, it is formed in a thin plate shape or a thin film shape. It is preferable to use a magnet because the cushioning property of the electrostatic chuck 2 and the peelability of both the magnets 3a and 3b are maintained.

  Further, as shown in FIGS. 2 and 3, as the attaching means 3, a magnet 3 a fixedly disposed on the base of the holding plate 1 and a magnet 3 b fixedly disposed on the opposing surface of the electrostatic chuck 2 are respectively provided. If the electrostatic chuck 2 is pulled away from the base surface 1a by the operation of the separating means 4, even if a slight misalignment in the XYθ direction occurs, Then, the magnetic force (repulsive force) due to the subsequent operation of the attaching means 3 is automatically returned to the original position.

  Further, when the electrostatic chuck 2 is pulled toward the base surface 1a of the holding plate 1 by the operation of the attaching means 3, the electrostatic chuck 2 is forcibly separated from the workpiece (upper substrate) A that has been moved. Instead of pulling the entire surface of 2 at the same time, as shown in the partial enlarged view of the main part of FIG. 1B, only the portion facing the outer peripheral end A1 of the moved workpiece A is first drawn and partially pulled. It is preferable that the separation gap S1 is partially formed between the workpiece A and the outer peripheral end A1 by deforming the workpiece A.

Next, a workpiece transfer method using such an electrostatic chuck device D will be described.
First, as shown in FIG. 1 (a), the attachment means 3 and the suction / adsorption means 5 draw the thin or thin electrostatic chuck 2 toward the base surface 1a of the holding plate 1 made of a rigid body. The electrostatic chuck 2a is smoothed along the base surface 1a and then bonded, and the workpiece A is electrostatically chucked on the electrostatic chuck 2.

  Subsequently, as shown in FIG. 1B, the electrostatic chuck 2 is pulled away from the base surface 1a of the holding plate 1 while the workpiece A is electrostatically adsorbed by the operation of the separating means 4. If the workpiece A is moved in parallel toward the other workpiece (lower substrate) B, the workpiece A does not become free, so it is transferred without being affected by gravity, etc. Temporarily fixed.

Further, immediately after this movement is completed, the power supply of the electrostatic chuck 2 is turned off, and the electrostatic adsorption function is stopped.
When the attachment means 3 and the suction suction means 5 are operated slightly later than that and the thin plate or film-like electrostatic chuck 2 is forcibly separated from the temporarily fixed work A, the electrostatic chuck 2 is around this time. Since the residual attracting force of the electrostatic chuck 2 is weakened, a separation gap S1 is formed between the workpiece A and the electrostatic attracting portion 2a of the electrostatic chuck 2, and the electrostatic chuck 2 is electrostatically discharged from the gap S1 portion. The suction part 2a is peeled off without difficulty.

  At the same time, the electrostatic chuck 2 in the form of a thin plate or thin film is slightly in the XYθ direction with respect to the base surface 1a of the holding plate 1 by magnets 3a and 3b in which electrodes of opposite magnetic poles are alternately arranged. Without being displaced, it automatically adheres to the original position and returns to the initial state.

As a result, even the workpiece A having extremely low rigidity can be transferred to a fixed position and reliably peeled regardless of the residual chucking force of the electrostatic chuck 2 or the non-uniformity of release of the electrostatic chucking force.
Furthermore, since the electrostatic chucking portion 2a of the electrostatic chuck 2 is smoothed along the base surface 1a of the holding plate 1 made of a rigid body, the electrostatic chucking portion 2a and the surface of the workpiece A are in contact with each other without any gap. The workpiece A is securely held by being electroadsorbed.

  Further, the electrostatic chuck 2 is partially deformed from a position facing the outer peripheral end A1 of the workpiece A, and a separation gap S1 is partially formed between the electrostatic chuck 2 and the outer peripheral end A1 of the workpiece A. For example, the separation gap S1 spreads between the electrostatic chucking portion 2a of the electrostatic chuck 2 and the surface of the workpiece A, and the residual chucking force is forcibly attenuated and disappears. Peelability can be improved.

  In the second embodiment, as shown in FIGS. 4 (a) and 4 (b), the electrostatic chuck 2 is formed larger than the base surface 1a of the holding plate 1 and the workpiece A, and the outer end portion 2d is formed as a stator. 2e is detachably fixed to the holding plate 1, or a part or the entire circumference of the outer end 2d is folded back and fixed to the holding plate 1 by the stator 2e, and the current is supplied. The electrostatic attraction part is connected to the part 2f to supply current to the electrode part 2c, and an elastically deformable bending part 2g is defined between the outer end part 2d and the electrostatic attraction part 2a. The configuration in which 2a is reciprocally movable in the vertical direction is different from the first embodiment shown in FIGS. 1 to 3, and the other configuration is the same as the first embodiment shown in FIGS. is there.

In the case of the illustrated example, the outer end 2d of the electrostatic chuck 2 is fixed in a frame shape over the entire circumference, or is fixed in a dot shape at appropriate intervals over the entire circumference of the outer end 2d. is doing.
As another example, the set of outer end portions 2d arranged in parallel of the electrostatic chuck 2 is fixed in parallel, or the set of parallel outer end portions 2d is fixed in a dot shape at appropriate intervals. Is also possible.

  Accordingly, in the second embodiment shown in FIG. 4, the electrostatic chuck 2 can be supported so as to reciprocate in the vertical direction without guide means (not shown), and the holding plate 1 can be operated by the operation of the separating means 4. When the electrostatic chuck 2 is pulled away from the base surface 1a, it returns to the original position without being displaced in the XYθ direction.

  Accordingly, as shown in FIGS. 2 and 3, the adhering means 3 includes a magnet 3 a fixedly arranged on the base of the holding plate 1 and a magnet 3 b fixedly arranged on the opposite surface of the electrostatic chuck 2 in the vicinity thereof. It is not necessary to arrange the electrodes of the opposite magnetic poles alternately, and it is possible to replace the magnet 3b of the electrostatic chuck 2 with a magnetic material such as a metal formed in a film shape by sputtering or the like. It is possible to reciprocate without displacement in the direction, and there is an advantage that the structure of the attaching means 3 can be simplified and the cost can be reduced as compared with the first embodiment shown in FIGS.

  As shown in FIGS. 5A to 5C, the third embodiment is an example of a substrate bonding machine using the electrostatic chuck device D described above, and the upper and lower base surfaces 1a and 1a of the upper and lower holding plates 1 and 1 '. Although a thin plate-like or thin-film electrostatic chuck 2 is disposed on 1a ', it supports the upper base surface 1a so as to be able to reciprocate in the vertical direction, and the upper and lower substrates A and B are supported on these electrostatic chucks 2. Each of the electrostatic chucks is electrostatically attracted, and after the alignment of the substrates A and B, the electrostatic chuck 2 located above the upper base surface 1a is kept electrostatically attracted by the operation of the separating means 4. By pulling apart and moving toward the lower substrate B, it is bonded to the lower substrate B via the annular adhesive C, and then the electrostatic chuck 2 is forced from the bonded upper substrate A by the operation of the attaching means 3. To the upper base surface 1a It shows the case be.

  Further, for example, an adhesive material, a mechanical one-touch coupling mechanism, or an adhesive is disposed between the lower base surface 1a 'of the lower holding plate 1' and the electrostatic chuck 2, and both of them are detachably attached. The electrostatic chuck 2 of the lower holding plate 1 ′ does not reciprocate in the vertical direction by the operation of the attaching means 3 and the separating means 4 as in the upper holding plate 1 described above.

  As shown in FIGS. 6A and 6B, a plurality of through holes 6 are formed in the lower base surface 1a ′ of the lower holding plate 1 ′ and the lower electrostatic chuck 2 in the Z (vertical) direction as required. As the separating means 7 for separating the bonded upper and lower substrates A and B from the surface of the electrostatic chuck 2, the tip portion is made of an insulating material. Bonding is completed by arranging the formed lift pins so as to be movable in the Z (vertical) direction or by controlling the operation so as to inject a gas such as nitrogen gas or air or other fluids upward. It is preferable to push up the upper and lower substrates A and B from the surface of the lower electrostatic chuck 2 to form a slight static elimination gap S2 of, for example, about 2 to 3 mm between the lower substrate B and the back surface B1.

  The separation means 7 is embedded in the lower electrostatic chuck 2 in the atmosphere or in a predetermined low vacuum in which a gap S2 is formed between the surface of the lower electrostatic chuck 2 and the back surface B1 of the lower substrate B. A high voltage is applied between the two or more electrode portions 2c applied from a high voltage power source (not shown), and the polarity of the voltage is reversed from the state of being applied when the lower substrate B is electrostatically attracted. Thus, by varying the voltage of these two or more electrode portions 2c, an electric field that neutralizes the charges remaining on the upper and lower substrates A and B is induced.

  In the illustrated example, the above-described electrostatic chuck device D uses the first embodiment shown in FIGS. 1 to 3. However, as another example, the second embodiment shown in FIG. 4 is used. It is also possible to do.

Next, the operation of the substrate bonding machine using such an electrostatic chuck device D will be described.
First, in the atmospheric pressure state shown by the solid line in FIG. 5A, the attachment means 3 and the suction suction means 5 actuate the thin plate or thin film electrostatic chuck 2 toward the upper base surface 1a. The upper and lower substrates A and B, which are smoothly bonded along the upper base surface 1a and transferred in this state by the transfer robot, are attached to the upper electrostatic chuck 2 attached to the upper holding surface 1a and the lower base surface 1a. The electrostatic chucks 2 attached on the upper side are respectively electrostatically attracted and held.

  After that, as indicated by the two-dot chain line in FIG. 5A, the upper and lower holding plates 1 and 1 'are moved close to each other by the operation of the elevating means to form a vacuum chamber S. The inside of the vacuum chamber S has a predetermined degree of vacuum. Then, the upper and lower holding plates 1 and 1 ′ are relatively adjusted and moved in the XYθ direction as they are, and the alignment operation of the upper and lower substrates A and B is performed.

After the alignment operation is completed, as shown in FIG. 5B, the upper electrostatic chuck 2 is separated from the upper base surface 1a while the upper substrate A is electrostatically attracted by the operation of the separating means 4. Thus, the upper substrate A is moved toward the lower substrate B.
Thereby, the upper and lower substrates A and B are instantaneously pressed with the annular adhesive C interposed therebetween, and the two are sealed and overlapped.

  In this superposition process, gas and fluid can be completely prevented from entering between the upper and lower substrates A and B, and the upper substrate A having extremely low rigidity has a thin plate shape or thin film shape existing thereon. Since the electrostatic chuck 2 serves as a cushioning material, even if slight unevenness occurs in the pressure applied to the annular adhesive C, the annular adhesive C or spacer (not shown) formed between the upper and lower substrates A and B is not shown. ) And so on.

Further, immediately after the movement of the upper substrate A is completed, the power supply of the upper electrostatic chuck 2 is cut off, and the electrostatic adsorption function is stopped.
After that, the inside of the vacuum chamber S is returned to the atmospheric pressure, the pressure is uniformly applied by the pressure difference generated between the inside and outside of both the substrates A and B, and the pressure gap generated between the inside and outside of both the substrates A and B is crushed to a predetermined gap. This completes the bonding process.

  Subsequently, as shown in FIG. 5 (c), the upper electrostatic chuck is moved from the upper substrate A bonded to the lower substrate B via the annular adhesive C by the operation of the adhering means 3 and the suction adsorbing means 5. 2 is pulled toward the upper base surface 1a, and both of them are peeled off.

At this time, the residual suction force of the upper electrostatic chuck 2 is extremely reduced by passing through the Paschen discharge region where the degree of vacuum in the vacuum chamber S is about several tens of Pa to several thousand Pa.
However, the upper substrate A held by the adhesive force of the annular adhesive C and the upper electrostatic chuck 2 may be difficult to peel off because their entire surfaces are in contact with each other.

Therefore, as described above, the entire surface of the upper electrostatic chuck 2 is not pulled away from the surface of the upper substrate A at the same time, but is partially deformed from the portion facing the outer peripheral end A1 of the bonded upper substrate A. If a gap for peeling is partially formed between the outer peripheral edge A1 of the upper substrate A, the gap for peeling is formed at once on the surface of the electrostatic chuck 2a of the electrostatic chuck 2 and the upper substrate A. Since it spreads and the residual attracting force is forcibly attenuated and disappears, the entire electrostatic attracting surface of the upper electrostatic chuck 2 is smoothly peeled off from the surface of the upper substrate A.
As a result, even the upper substrate A having extremely low rigidity can be securely bonded and peeled off at a fixed position regardless of the residual attracting force of the upper electrostatic chuck 2 or the uneven release of the electrostatic attracting force.

  Further, the upper electrostatic chuck 2 peeled off from the surface of the upper substrate A adheres to the upper base surface 1a, and thereafter, the upper and lower holding plates 1 and 1 'are moved away from each other by the operation of the elevating means. To return to the initial state.

  The surroundings of the upper and lower substrates A and B that have been bonded together in such a situation are in the air or in a low vacuum of 100 Pa or higher. In this atmosphere, as shown in FIGS. As shown in the drawing, the lift pin is raised as the separating means 7 from the plurality of through holes 6 opened in the base surface 1a 'of the lower holding plate 1' and the lower electrostatic chuck 2, or for example, nitrogen gas or air The upper and lower substrates A and B, which have been bonded together, are pushed up from the surface of the lower electrostatic chuck 2 by ejecting the gas or other fluid upward, for example, between 2 and the back surface B1 of the lower substrate B. A slight static elimination gap S2 of about 3 mm is formed.

In this state, if the voltage of two or more electrode portions 2c embedded in the lower electrostatic chuck 2 is changed, the lower electrostatic chuck 2 is peeled off from the state where the lower substrate B made of glass is attached. An electric field (specifically, an alternating electric field) that neutralizes the charges remaining on the upper and lower substrates A and B is induced by the peeling electrification generated at the moment of the application.
Thereby, in this induced electric field part, a part of atmospheric gas such as air is instantaneously ionized and ionized, that is, neutral molecules are separated into positive and negative charges, so that they remain on the lower substrate B. The charge is eliminated by acting to neutralize the charge.

Further, the upper and lower substrates A and B are transferred by the transfer robot described above, and the upper electrostatic chuck 2 attached to the upper base surface 1a and the lower electrostatic chuck 2 attached on the lower base surface 1a '. There is a possibility that glass cullet (fragment) or the like may enter when being transferred to and set.
In this case, the surface of the electrostatic chuck 2 such as the dielectric 2a is partially formed by biting the cullet between the electrostatic chucks 2 in accordance with the electrostatic adsorption between the upper and lower substrates A and B. May break down and break down.

  Even in such a case, since the electrostatic chuck 2 having a thin plate shape or a thin film shape is detachably disposed on the upper and lower base surfaces 1a and 1a ', these electrostatic chucks 2 can be easily replaced and are excellent in maintainability. There is also an advantage.

In addition, the electrostatic chuck device D of the present invention detachably holds a glass substrate or a plastic film substrate used for a liquid crystal display (LCD), a plasma display (PDP) or a flexible display panel as the workpieces A and B. Although the case where it is provided in a substrate bonding machine to be combined is shown, it is not limited to this, and it is provided in a substrate assembly apparatus other than this substrate bonding machine, a substrate transfer apparatus for transferring a substrate, or a glass substrate for an LCD panel Other substrates may be adhered and held.
Furthermore, although the board | substrate bonding machine which bonds the two board | substrates A and B in the vacuum was demonstrated, it is not limited to this, The board | substrate bonding machine which bonds the board | substrates A and B in air | atmosphere may be sufficient. The same effects as the above-described vacuum bonding machine can be obtained.

  In the illustrated example, the electrostatic chuck 2 is supported only on the upper base surface 1a of the upper holding plate 1 so as to reciprocate in the vertical direction. However, the present invention is not limited thereto, and the lower base surface of the lower holding plate 1 'is not limited thereto. The electrostatic chuck 2 is supported so as to be movable in the Z direction with respect to 1a '. Further, the lower holding plate 1' is provided with an attaching means 3 and an isolating means 4, and this attaching means 3 provides a lower base for the lower holding plate 1 '. An electrostatic chuck 2 is attached to the surface 1a ', and the lower substrate B is electrostatically adsorbed by the attached electrostatic chuck 2, and the electrostatic chuck 2 and the lower substrate B are integrated with the separating means 4 as below. The electrostatic chucking function of the electrostatic chuck 2 is stopped while being separated from the holding plate 1 ′ toward the open position, and then the electrostatic chuck 2 is stopped. Thereafter, only the electrostatic chuck 2 is moved from the open position to the lower holding plate 1 by the attaching means 3. The surface of the lower substrate B moved back to the open position By peeling off the electrostatic chuck 2, substrate A, may be bonded operation B is performed.

BRIEF DESCRIPTION OF THE DRAWINGS It is a vertical front view which shows Example 1 of the workpiece | work transfer method and electrostatic chuck apparatus of this invention, and has shown to the operation process order to (a) (b). FIG. 2 is a reduced bottom view taken along line (2)-(2) in FIG. FIG. 2 is a reduced enlarged plan view taken along line (3)-(3) in FIG. It is a vertical front view which shows Example 2 of the workpiece | work transfer method and electrostatic chuck apparatus of this invention, and has shown to (a) and (b) in order of the operation | movement process. It is a reduction | decrease longitudinal front view which shows Example 3 of the bonding machine using the workpiece | work transfer method and electrostatic chuck apparatus of this invention, (a)-(c) has shown the bonding method of the board | substrate in order of process. It is the reduction | decrease vertical front view which shows the time of static elimination, and has shown to the operation process order to (a) (b).

Explanation of symbols

A Workpiece (upper substrate) A1 Outer peripheral edge B Workpiece (lower substrate) C Ring adhesive D Electrostatic chuck device S Vacuum chamber S1 Separation gap S2 Static elimination gap 1 Upper holding plate 1a Base surface 1 'Lower holding plate DESCRIPTION OF SYMBOLS 1a 'Base surface 2 Electrostatic chuck 2a Electrostatic adsorption part 2b Dielectric body 2c Electrode part 2d Outer end part 2e Stator 2f Current supply part 2g Bending part 3 Adhering means 3a Magnet 3b Magnetic body (magnet) 4 Isolating means 4a Vent 4b Sealed space 5 Suction / adsorption means 6 Through hole 7 Separation means

Claims (5)

In a workpiece transfer method in which a workpiece is attracted and held by an electrostatic chuck of a holding plate, and the held workpiece is released and placed at a predetermined position.
The holding plate is provided with attachment means for pulling the electrostatic chuck to the holding plate so as to be detachable, and isolation means for pulling the electrostatic chuck away from the holding plate. The attachment means attaches the electrostatic chuck to the holding plate. The workpiece is attached and held by the attached electrostatic chuck, and the electrostatic chuck and the workpiece are integrally separated from the holding plate by the separating means, and the electrostatic chucking function of the electrostatic chuck is stopped. Thereafter, the workpiece transfer method is characterized in that only the electrostatic chuck is attached again to the holding plate by the attaching means, and the workpiece is placed in the open position while remaining. 2. The work transfer method according to claim 1, wherein the electrostatic chuck is formed in a thin plate shape or a film shape, and is supported so as to be movable in a direction intersecting with a smooth base surface of a rigid holding plate. When depositing again only electrostatic chuck to the holding plate by the attachment means, the electrostatic attraction of the electrostatic chuck, by partially deforming attract a portion facing the outer peripheral edge portion of the workpiece ahead The workpiece transfer method according to claim 2 , wherein a gap for forcibly peeling the electrostatic chuck from the workpiece is partially formed between the electrostatic chucking portion of the electrostatic chuck and the outer peripheral end portion of the workpiece. An electrostatic chuck for electrostatically attracting the workpiece, and holding plate for holding the workpiece through the electrostatic chuck, and attachment means for removably adhering the electrostatic chuck to the holding plate, the electrostatic from the holding plate electrostatic chucking and isolation means for isolating the click, the sequestered electrostatic chuck with and a said attachment means or suction attracting means placed along attract to the holding plate, stop the electrostatic adsorption function of the electrostatic chuck, the An operating means for operating the separating means and the adhering means or the suction adsorbing means respectively;
The actuating means operates the isolating means to move the work to the work transfer position together with the electrostatic chuck in a state where the electrostatic chuck that has electrostatically attracted the work is adhered to the holding plate by the attaching means. After that, the electrostatic chucking function of the electrostatic chuck is stopped, and then the attachment means or the suction suction means is operated to peel the electrostatic chuck from the workpiece and adhere to the holding plate by the attachment means. An electrostatic chuck device characterized by that. A substrate bonding method for bonding a pair of substrates using the electrostatic chuck device according to claim 4 ,
One of the pair of substrates is opposed to the other, and is detachably held on the holding plate in the electrostatic chuck device via the electrostatic chuck, and the electrostatic chuck is moved from the holding plate to the one substrate. distancing remains electrostatically attracted, to move toward the base plate of this to the other substrate, substrate bonding method characterized in that bonding the two substrates by an annular adhesive.

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