WO2008041293A1

WO2008041293A1 - Work transferring method, electrostatic chuck device, and board joining method

Info

Publication number: WO2008041293A1
Application number: PCT/JP2006/319540
Authority: WO
Inventors: Yoshikazu Ohtani
Original assignee: Shin-Etsu Engineering Co., Ltd.
Priority date: 2006-09-29
Filing date: 2006-09-29
Publication date: 2008-04-10
Also published as: JP4043506B2; CN101316777B; TW200815268A; TWI412480B; JPWO2008041293A1; CN101316777A

Abstract

An electrostatic chuck device enabling even a thin work with low rigidity to be releasedly placed without causing deformation and displacement during the movement. An electrostatic chuck (2) is attached to a holding plate (1) by an attaching means (3). A work (A) is chucked and held by the attached electrostatic chuck (2). The electrostatic chuck (2) and the work (A) are integrally separated from the holding plate (1) by a separating means (4). Since the work (A) is not brought into a free state, it can be transferred to the release position without being affected by the gravity. When only the electrostatic chuck (2) is re-attached to the holding plate (1) by the attaching means (3) after the electrostatic attracting function of the electrostatic chuck (2) is stopped, the electrostatic chuck (2) is separated from the surface of the work (A) moved to the release position, and the work (A) is left at the release position and placed.

Description

Technical field of workpiece transfer method, electrostatic chuck device and substrate bonding method

[0001] The present invention can be applied to a process for producing a flat panel display such as a liquid crystal display (LCD) or a plasma display (PDP), a flexible display, and a glass substrate such as CF glass or TFT glass. Substrate assembling equipment, including a substrate laminating machine, which detachably holds and attaches synthetic resin substrates such as PES (Poly-Ether-Sulphone) plastic films, and insulation of such substrates The present invention relates to a workpiece transfer method and an electrostatic chuck device used in a substrate transfer device for transferring a workpiece (object to be processed) such as a body, a conductor or a semiconductor wafer, and a substrate bonding method using the same.

Specifically, the method includes a workpiece transfer method in which a workpiece is attracted 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.

Background art

Conventionally, as a substrate laminating machine for superimposing two substrates, a pressure plate is an electrostatic chuck composed of an insulating member having an electrode plate built therein, and a glass substrate is held as a workpiece on the electrostatic chuck. After aligning the upper and lower substrates in the XY direction, the vacuum chamber is depressurized, and when the vacuum chamber reaches a desired degree of vacuum, the electrostatic adsorption function of the pressure plate is released. In some cases, the upper substrate is dropped onto the lower substrate, the upper and lower substrates are overlapped, and then the pressure plate is lowered to pressurize the upper and lower substrates so that the distance between them is bonded to a predetermined gap (for example, Patent Document 1).

In conjunction with the release of the upper substrate (upper substrate) by the electrostatic chuck (electrostatic chucking means), the back side force gas of the upper substrate is ejected, and this gas is ejected from the electrostatic chuck surface of the upper holding plate. By forcibly injecting between the back surface of the upper substrate and destroying the adhesion state between the electrostatic adsorption surface and the substrate surface and peeling them off, the electrostatic adsorption force between them is forcibly attenuated and disappears. At the same time, the drop force on the lower substrate (lower substrate), that is, the acceleration of the drop, is forcibly acted on by the pressure of the injected gas. In some cases, the upper substrate moves onto the lower substrate without being changed in posture while being held by the electroadsorption means, is crimped, and the upper and lower substrates are sealed and overlapped (for example, see Patent Document 2).

Patent Document 1: Japanese Patent Laid-Open No. 2001-166272 (Page 6, FIG. 8)

Patent Document 2: Japanese Patent No. 3721378 (Page 8, Figure 1)

Disclosure of the invention

Problems to be solved by the invention

[0004] However, in such a conventional workpiece transfer method or electrostatic chuck apparatus, in the case of Patent Document 1, the workpiece (upper substrate) is freely dropped in a vacuum by releasing the electrostatic attraction function. Since the substrate suction force by the electric chuck continues to operate even if the power supply is shut off, the substrate suction force does not immediately disappear, and subsequent release of the substrate suction force causes unevenness of release. The interface with the workpiece begins to peel partially, and finally the entire surface of the workpiece is peeled off and falls freely.

As a result, the workpiece (upper substrate) is free to fall while rotating around the last peeled point, causing an error in the alignment between the upper and lower substrates, and sealing with free fall pressure. There was a problem that air was easily mixed due to incompleteness.

In addition, the workpiece (upper substrate) partly drops due to gravity at the point where it first begins to peel off against the electrostatic chucking surface, and tilting occurs, and the tilting force tends to change depending on the situation. However, it is impossible to correct during free fall, and it is difficult to correct even after falling on the lower substrate, and the predetermined parallelism cannot be achieved. The force of the display and plasma display substrates that are starting to be manufactured up to over 1000mm on a side tends to be large. Even if the substrate is enlarged, the same degree of parallelism as a small substrate is required. In particular, if one side of the substrate exceeds 1000 mm, the Z-direction interval is extremely small compared to the size in the XY direction, so it is ideal to move these upper and lower substrates closer together, but in reality, Very difficult to It is.

In such an environment, if a large upper substrate with a side of more than 1000 mm is tilted even slightly, the distance in the Z direction is extremely small compared to the size in the XY direction. The pre-applied liquid crystal sealing material (annular adhesive) may cause problems such as damage to the film surfaces of both substrates, and normal bonding cannot be expected! There is.

In addition, in the case of Patent Document 2, the back side of the workpiece (upper substrate) is also peeled off by injecting gas between the workpiece and the workpiece 0.7-7. 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 electrostatic chucking force could be reliably peeled off by the gas in which the peeling gas is easily transmitted uniformly in the surface direction. By the way, in recent years, there are many applications for liquid crystal displays that emphasize light weight, such as mobile phones and laptop computers. In such applications, the glass thickness of the workpiece is very thin, about 0.5 mm or less. In addition, the workpieces used for flexible displays become plastic films such as PES (Poly-Ether Sulphone) with a thickness of several hundreds of um. Such workpieces such as glass substrates and plastic films of about 0.5 mm or less have also been used with conventional forces. Since the rigidity is extremely low compared to glass substrates of 0.7 to 1.1 mm, gas for peeling is used. Even if the spray is sprayed, the workpiece is partially extruded and deformed, and the flow path of the peeling gas concentrates on the deformed portion, and the workpiece may not be reliably peeled off due to the residual adsorption force. At the same time, there is a possibility that the part is intensively stretched due to extrusion deformation by the air current for peeling at the time of peeling, and partial distortion remains. Among the present inventions, the inventions according to claims 1 and 4 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 securely hold and transfer the workpiece.

The invention described in claim 3 is intended to improve the peelability of the workpiece in addition to the object of the invention described in claim 1 or 2.

In addition to the object of the invention described in claim 4, the invention described in claim 5 adheres at a fixed position and reliably peels off even if the substrate has low rigidity, regardless of unevenness in releasing the electrostatic adsorption force. It is for the purpose.

Means for solving the problem

In order to achieve the above-described object, the invention according to claim 1 of the present invention is configured such that the electrostatic chuck is formed in a thin plate shape or a film shape and is movably supported, and is opposed to the electrostatic chuck. The surface of the workpiece is electrostatically attracted, and this attracting position force moves the electrostatic chuck to the open position while the workpiece is electrostatically attracted, and stops the electrostatic chuck function of the electrostatic chuck, thereby releasing the electrostatic chuck. As for the force, only the electrostatic chuck is reversely moved toward the suction position, and the surface force of the workpiece moved to the open position is also characterized by peeling off the electrostatic chuck. The invention according to claim 2 is a configuration in which the electrostatic chuck is formed in a thin plate shape or a film shape in the configuration of the invention according to claim 1 and intersects with a smooth base surface of the holding plate having a rigid body force. It is characterized by the addition of a structure that is movably supported.

The invention described in claim 3 is the configuration of the invention described in claim 1 or 2, wherein the electrostatic chucking portion of the electrostatic chuck is also partially deformed at the part force facing the outer peripheral end portion of the workpiece. It is characterized by the addition of a structure in which a separation gap is partially formed between the outer peripheral edge of the hook.

Further, the invention according to claim 4 is a state in which the electrostatic chuck is movably supported in a direction crossing the workpiece side surface of the holding plate, and the electrostatic chuck is placed along the workpiece side surface. The surface of the workpiece is electrostatically attracted, and this attracting position force also moves the electrostatic chuck to the open position while the workpiece is electrostatically attracted, and stops the electrostatic chuck function of the electrostatic chuck, The invention according to claim 5, wherein only the electrostatic chuck is reversely moved toward the suction position and the surface force of the workpiece moved to the open position is also peeled off from the electrostatic chuck. The electrostatic chuck device according to claim 4 is provided in either one or both of the pair of holding plates, and the two substrates as the workpiece are opposed to each other and held detachably between the holding plates. From either side of the plate The electrostatic chuck of the chuck device is separated while one substrate is electrostatically attracted, the one substrate is moved toward the other substrate, and both substrates are bonded together with an annular adhesive. Is. The invention's effect

[0007] The invention described in claim 1 of the present invention is that 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. By separating the holding plate force with the separating means as a single unit, 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. After that, by attaching only the electrostatic chuck to the holding plate again by the attaching means, the surface of the work moved to the open position is peeled off from the electrostatic chuck, and the work is left 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 with its posture stabilized compared to the conventional one in which the electrostatic posture is uneven due to the release of electrostatic adsorption and the posture of the workpiece tends to become unstable.

In addition, the separation gas flow path does not concentrate on a specific part even in the case of a low-rigidity workpiece, as compared to the conventional type in which the workpiece is peeled off by the gas injection pressure. It is excellent in workability.

[0008] In addition to the effect of the invention of claim 1, the invention of claim 2 forms an electrostatic chuck in a thin plate shape or a film shape, and intersects with the smooth base surface of the holding plate having a rigid body force. The base plate and the base plate are electrostatically adsorbed by flattening at least the electrostatic chuck part of the electrostatic chuck along the smooth base surface with rigid body force by the support means. Since the workpiece does not become free by separating the base surface force electrostatic chuck while the workpiece is electrostatically attracted by the operation of the separation means, the workpiece does not become free. Thereafter, the surface force of the moved workpiece is peeled off by the operation of the adhering means, and the electrostatic chuck is peeled off and returned to the initial state along the base surface.

Accordingly, the workpiece can be reliably held and transferred.

[0009] In the invention of claim 3, in response to the effect of the invention of claim 1 or 2, the electrostatic chucking portion of the electrostatic chuck is partially deformed at a position facing the outer peripheral end of the workpiece. , Outside the workpiece By partially forming a separation gap between the peripheral edge and the peripheral edge, the separation gap widens between the electrostatic chuck portion of the electrostatic chuck and the surface of the workpiece, and the residual suction force is reduced. Forced to decay and disappear.

Therefore, the peelability of the workpiece can be improved.

[0010] In the invention of claim 4, the electrostatic chuck is movably supported in a direction crossing the workpiece side surface of the holding plate, and the electrostatic chuck is placed along the workpiece side surface. The surface of the cake is electrostatically attracted, and this attracting position force is also affected by gravity, etc. because the workpiece does not become free by moving the electrostatic chuck while the workpiece is electrostatically attracted. The electrostatic chuck function of the electrostatic chuck is stopped and the electrostatic force of the electrostatic chuck is moved back to the suction position. The electrostatic chuck also peels off the surface force.

[0011] In addition to the effect of the invention of claim 4, the invention of claim 5 pulls the electrostatic chuck from one of the two holding plates while the one substrate is electrostatically attracted to the other substrate. The two substrates are bonded to each other with an annular adhesive, so that one of the substrates does not become free, so it is transported and bonded accurately without being affected by gravity, etc. The electrostatic chuck is easily peeled off from one of the substrates held by the adhesive force. Therefore, even if the substrate has low rigidity, it can be securely bonded and peeled off at a fixed position regardless of the unevenness in releasing the electrostatic adsorption force.

As a result, it is possible to prevent misalignment between the two substrates and to ensure a sealed space compared to conventional substrate bonding machines that allow the upper substrate to fall freely by releasing electrostatic adsorption. In addition to preventing air from being mixed, there is no tilt due to the peeling of the substrate on the surface with electrostatic attraction, so that a predetermined degree of parallelism can be achieved, and the force is large on a substrate with a side exceeding 1000 mm. Even in such a case, the sealing material for sealing liquid crystal (annular adhesive) caused by the inclination of the upper substrate can completely prevent troubles such as damaging the film surfaces of both substrates.

Furthermore, even if the substrate has low rigidity compared to the conventional substrate bonding machine that directly peels only the substrate with the gas injection pressure, the gas flow for peeling does not concentrate on a specific part, and the substrate has high rigidity. As with, it can be peeled off reliably and has excellent workability.

Even if the surface of the electrostatic chuck breaks down due to the penetration of foreign matter, the holding plate and the thin or film-like electrostatic chuck are separate parts. On the other hand, since the electrostatic 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. Occupancy rate does not decrease and stable production can be expected.

BEST MODE FOR CARRYING OUT THE INVENTION

[0012] Workpiece transfer method and electrostatic chuck apparatus according to the present invention D force Workpieces A and B can be detachably attached to a glass substrate or a plastic film substrate used for a liquid crystal display (LCD), plasma display (PDP), or flexible display panel. This shows the case where it is installed in a substrate bonding machine that holds and bonds to the substrate.

[0013] This substrate laminating machine is a fixed plate formed into a flat plate having a thickness that does not deform (stagnate) with a rigid body such as metal or ceramics as shown in Figs. 5 (a) to 5 (c). A pair of upper and lower holding plates 1, 1 ′, which is a board force, is arranged, and the two substrates A and B are detachably held on the parallel opposing surfaces of these upper and lower holding plates 1, 1 ′. After the vacuum chamber S formed in the surrounding area reaches a predetermined degree of vacuum, the upper and lower holding plates 1, \ 'are relatively adjusted and moved in the ΧΥ Θ direction (horizontal direction in the drawing) to obtain substrates A and B. After aligning each other, at least one of the substrates A and B is peeled off and overlapped by the smooth surface force of the upper and lower holding plates 1, \ ', and then the vacuum break in the vacuum chamber S is performed. The pressure difference between the substrates A and B is pressurized to a predetermined gap by the pressure difference generated between the substrates A and B.

[0014] Specifically, the upper and lower holding plates 1, \ 'as shown by the solid line in FIG. (Not shown) is supported so as to be relatively movable in the z direction (vertical direction in the drawing). In an atmosphere of atmospheric pressure, the upper and lower holding plates 1 are separated from each other in the vertical direction, The substrates A and B transferred by the transfer robot (not shown) are set and held respectively.

[0015] Thereafter, the upper and lower holding plates 1 and 1 'are moved close to each other by the operation of the elevating means as shown by the two-dot chain line in Fig. 5 (a), and the 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) and a predetermined degree of vacuum is reached, the horizontal holding means (not shown) is operated to operate the upper and lower holding plates 1. , 1 'is adjusted and moved in the XY 0 direction relative to the other, so that rough alignment and fine alignment are sequentially performed as alignment between the substrates A and B held by them.

[0016] After these alignments are completed, either one of the substrates A and B held on the upper and lower holding plates 1, 1 'as shown in Fig. 5 (b) is moved toward the other, An annular adhesive (sealant) C on the lower substrate B is sandwiched between the two by applying pressure instantaneously with the C sandwiched between them.

[0017] After that, as shown in Fig. 5 (c), the upper and lower holding plates 1, \ 'are moved away from each other by the operation of the elevating means, and the intake means is operated in reverse at substantially the same time. Alternatively, air or nitrogen is supplied into the vacuum chamber S by another mechanism, and the atmosphere in the vacuum chamber S is returned to atmospheric pressure. Then, the liquid crystal is squeezed to a predetermined gap to complete the bonding process.

[0018] Then, the electrostatic chuck device D of the present invention is configured by the above-described upper and lower holding plates 1, \ 'also having rigid body force and the electrostatic chuck 2 that holds the substrates A and B by suction.

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, and the upper holding plate 1 further includes the electrostatic chuck. There are provided attachment means 3 for pulling 2 toward each smooth surface and detachably adhering to each smooth surface, and isolation means 4 for separating the electrostatic chuck 2 from each smooth surface.

The attachment means 3 attaches the electrostatic chuck 2 to the smooth surface of the upper holding plate 1, and the attached electrostatic chuck 2 electrostatically adsorbs the upper substrate A. The upper substrate A is integrated and separated from the upper holding plate 1 toward the open position by the separating means 4 and moved in parallel. Then, the electrostatic chucking function of the electrostatic chuck 2 was stopped, and then the electrostatic chuck 2 alone was moved back to the upper holding plate 1 by the attachment means 3 and moved to the open position. Upper Surface force of substrate A By peeling off the electrostatic chuck 2, the above-described bonding operation of the substrates A and B is performed.

[0020] The electrostatic chuck 2 is made of a dielectric thin film or a thin film made of an insulating organic material such as polyimide, polyetheretherketone (PEEK), or polyethylene naphthalate (PEN). In addition, an electrode portion 2c which also becomes a conductive paste or a conductive foil pattern patterned by screen printing or the like is integrally laminated.

[0021] The electrode portion 2c is formed insulated from the surroundings, and is 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 tooth shape.

In addition, the electrode part 2c of the electrostatic chuck 2 that is supported so as to be able to reciprocate 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 its electrostatic adsorption function is stopped. Has been.

[0022] The attaching 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 the surface of the electrostatic chuck 2 facing the upper surface. In addition, a magnet attracted by the magnet and a magnetic material 3b such as a metal formed in a film shape by sputtering, for example, or a structure other than an adhesive other than a magnetic force such as a mechanical one-touch connection mechanism The electrostatic chuck 2 is detachably bonded to the smooth surface by their magnetic force and adhesive force.

[0023] The isolating 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, 1 'toward the opposite surface of the electrostatic chuck 2. Either the force that presses the electrostatic chuck 2 or the force that presses the electrostatic chuck 2 with a driving body that reciprocates up and down, such as an air cylinder, or the magnets 3a and 3b that are provided oppositely as the attachment means 3 By converting the magnetic poles of the magnets 3a and 3b and repelling them with the same magnetic poles, the electrostatic chuck 2 is also separated in parallel. Embodiments of the present invention will be described below with reference to the drawings. Example 1

This embodiment 1 is a pedestal (base) made of a rigid body in which the magnet 3a of the attachment means 3 is embedded in the smooth surface of the holding plate 1 as shown in FIGS. 1 (a) and 1 (b). And a thin plate-like or thin-film electrostatic chuck 2 in which the magnet 3b of the attachment means 3 is laminated on a smooth base surface la on the tip surface thereof, as guide means (not shown), etc. The separation means 4 is supported by the above-mentioned separating plate 4 and the force for injecting a gas or fluid toward the electrostatic chuck 2 from the holding plate 1 and the vent hole 4a provided in the base. By raising the internal pressure of the sealed space 4b defined between the base surface la and the electrostatic chuck 2, the entire electrostatic chuck 2 is resisted against the magnetic force of the attaching means 3 by the base surface la. This shows the case of moving away from the plane in parallel.

Further, 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 sucked by, for example, a vacuum pump. A pipe is connected to a source (not shown), and this suction path is used as a vent hole 4a of the isolation means 4.

[0026] In the drawing, the rigidity of the workpiece A of about 0.5 mm or less is extremely low by supporting the electrostatic chuck 2 so as to reciprocate in the vertical direction with respect to the smooth surface of the upper holding plate 1. Although only an example of moving while holding the surface of the upper substrate by suction is shown, the lower substrate is supported by supporting the electrostatic chuck 2 in a reciprocating manner in the vertical direction with respect to the smooth surface of the lower holding plate. The same applies when moving while holding the surface of B by suction.

[0027] 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 opposite surface of the electrostatic chuck 2, a thin plate or a thin film is used. If the magnet formed in the shape is used, the cushioning property of the electrostatic chuck 2 is preferable because the peelability of both the magnets 3a and 3b is maintained.

Further, as the attaching means 3 as shown in FIG. 2 and FIG. 3, a magnet 3 a fixedly arranged on the pedestal of the holding plate 1 and a magnet 3 b fixedly arranged on the opposing surface of the electrostatic chuck 2. By arranging the electrodes of opposite magnetic poles alternately in the vicinity of each other, when the electrostatic chuck 2 is pulled away from the base surface la by the operation of the separating means 4, a slight positional deviation in the ΘΘ direction is made. Even if this occurs, the magnetic force (repulsive force) due to the subsequent operation of the attachment means 3 will return to the original position It automatically returns.

[0029] In addition, when the electrostatic chuck 2 is attracted to the base surface la of the holding plate 1 by the operation of the attaching means 3, the workpiece (upper substrate) A that has been moved is forcibly separated. Instead of pulling the entire surface of the electrostatic chuck 2 at the same time, only the part facing the outer peripheral edge A1 of the moved workpiece A as shown in the enlarged partial view of the main part in FIG. It is preferable that a separation gap S1 is partially formed between the outer peripheral end A1 of the workpiece A by pulling and partially deforming.

Next, a workpiece transfer method using such an electrostatic chuck device D will be described.

First, by the operation of the adhering means 3 and the suction suction means 5, the electrostatic chuck 2 in the form of a thin plate or thin film is attracted toward the base surface la of the holding plate 1 made of a rigid body as shown in FIG. The electrostatic chucking portion 2a is smoothened and force-bonded along the base surface la, and the workpiece A is electrostatically chucked to the electrostatic chuck 2.

[0031] Subsequently, the electrostatic chuck 2 is pulled away from the base surface 1a of the holding plate 1 as shown in FIG. When this work A is moved in parallel toward the other work (lower substrate) B, the work A does not become free, so it is transferred without being affected by gravity, etc. Temporarily fixed to the other workpiece B.

[0032] Immediately after this movement is completed, the power supply of the electrostatic chuck 2 is cut off, and the electrostatic adsorption function is stopped.

Slightly later than that, the attachment means 3 and the suction suction means 5 are operated, and the temporarily fixed workpiece A force is also forcibly separated from the thin plate-like or film-like electrostatic chuck 2. Since the residual attracting force of the workpiece is weakened, there is a separation gap S1 between the workpiece A and the electrostatic chucking part 2a of the electrostatic chuck 2, and this partial force of the gap S1 is also electrostatic chuck 2 The electrostatic attracting part 2a peels off without difficulty.

At the same time, the electrostatic chuck 2 in the form of a thin plate or thin film is XY 0 with respect to the base surface la of the holding plate 1 by magnets 3a and 3b in which electrodes of opposite magnetic poles are alternately arranged. It automatically attaches to the original position without any slight displacement in the direction and returns to the initial state. [0034] Thereby, even the workpiece A having extremely low rigidity can be transferred to a fixed position and reliably peeled regardless of the residual adsorption force of the electrostatic chuck 2 or the uneven release of the electrostatic adsorption force.

Furthermore, since the electrostatic chucking part 2a of the electrostatic chuck 2 is smoothed along the base surface la of the holding plate 1 which also has a rigid body force, the electrostatic chucking part 2a and the surface of the workpiece A are in contact with each other without any gap. It is electrostatically attracted and workpiece A can be held securely.

[0035] Further, the electrostatic chuck 2 is also partially deformed at the part force 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. If formed, the separation gap S 1 spreads between the electrostatic chucking part 2a of the electrostatic chuck 2 and the surface of the workpiece A, and the residual suction force is forcibly attenuated. Since it disappears, the peelability of work A can be improved.

Example 2

In Example 2, the electrostatic chuck 2 as shown in FIGS. 4 (a) and 4 (b) is formed larger than the base surface la of the holding plate 1 and the workpiece A, and the outer ends thereof are formed. The portion 2d is detachably fixed to the holding plate 1 by the stator 2e, 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. At the same time, it is connected to the current supply part 2f to supply current to the electrode part 2c, and an elastically deformable stagnation part 2g is defined between the outer end part 2d and the electrostatic adsorption part 2a. Unlike the first embodiment shown in FIGS. 1 to 3, the other configurations are the same as those shown in FIGS. 1 to 3. Same as Example 1.

[0037] 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 at appropriate intervals over the entire circumference of the outer end 2d. It is fixed in a dot shape.

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. It 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 a guide means (not shown), and the above-described holding means can be operated by the operation of the separating means 4. When the electrostatic chuck 2 is pulled away from the base surface la of the holding plate 1, it returns to its original position without being displaced in the Θ Θ direction. Accordingly, as the attaching means 3, a magnet 3a fixedly arranged on the base of the holding plate 1 as shown in FIGS. 2 and 3, and a magnet 3b fixedly arranged on the opposing surface of the electrostatic chuck 2 are respectively provided. It is no longer necessary to arrange the electrodes of the opposite magnetic poles alternately in the vicinity of the magnet, and instead of the magnet 3b of the electrostatic chuck 2, a magnetic material such as a metal formed in a film shape by sputtering or the like is disposed and fixed. However, it can be reciprocated in the Θ direction without displacement, and the structure of the attachment means 3 can be simplified and the cost can be reduced compared to the first embodiment shown in FIGS. There is a point.

Example 3

[0040] Example 3 is an example of a substrate bonding machine using the above-described electrostatic chuck device D as shown in FIGS. 5 (a) to 5 (c). Although a thin plate or thin film electrostatic chuck 2 is disposed on each of the surfaces la and la ', the upper and lower substrates A are supported on these electrostatic chucks 2 by reciprocating in the vertical direction only on the upper base surface la. , B are electrostatically attracted, and after the alignment of the substrates A, B described above, the upper chuck A is electrostatically attracted to the upper electrostatic chuck 2 from the upper base surface la by the operation of the separating means 4. As it is pulled apart and moved toward the lower substrate B, it is bonded to the lower substrate B via the annular adhesive C, and then the bonded upper substrate A force electrostatic chuck by the operation of the adhering means 3 This shows a case where 2 is forcibly separated and returned to the upper base surface 1a.

[0041] Further, the lower holding plate! / Between the lower base surface 1 and the electrostatic chuck 2, for example, an adhesive, mechanical one-touch coupling mechanism, or adhesive can be placed, and both can be attached and detached. Like the upper holding plate 1, the lower holding plate: The electrostatic chuck 2 does not reciprocate vertically.

[0042] If necessary, this lower holding plate as shown in Fig. 6 (a) and (b)! In the lower base surface 1 and the lower electrostatic chuck 2, a plurality of through holes 6 are penetrated and opened in a straight line in the Z (vertical) direction, respectively. As separating means 7 for separating the completed upper and lower substrates A and B from the surface of the electrostatic chuck 2, a force for disposing a lift pin whose tip is formed of an insulating material movably in the Z (vertical) direction, or for example By controlling the operation so that a gas such as nitrogen gas or air and other fluids are jetted upward, the upper and lower substrates A and B, which have been bonded together, are pushed up by the surface force of the lower electrostatic chuck 2 as well. Back side of board B It is preferable to form a slight static elimination gap S2 of about 2 to 3 mm, for example, with the surface Bl.

[0043] The lower electrostatic chuck 2 is formed in the atmosphere or in a predetermined low vacuum in which the gap S2 is formed between the surface of the lower electrostatic chuck 2 and the rear surface B1 of the lower substrate B by the separating means 7. A high voltage is applied from a high voltage power source (not shown) between two or more electrode parts 2c embedded in the substrate, and is applied when the lower substrate B is electrostatically attracted. The electric field that neutralizes the charge remaining on the upper and lower substrates A and B is induced by changing the voltage of these two or more electrode portions 2c by repeatedly inverting the polarity.

In the illustrated example, Example 1 shown in FIGS. 1 to 3 was used as the electrostatic chuck device D described above, but the example shown in FIG. 4 is not shown as another example. Example 2 can also be used.

Next, the operation of the substrate bonding machine using the electrostatic chuck device D will be described.

First, in the atmospheric pressure state shown by the solid line in FIG. 5 (a), a thin plate or thin film electrostatic chuck 2 is bowed toward the upper base surface la by the operation of the adhering means 3 and the suction suction means 5. The upper and lower substrates A and B transferred by the transfer robot in this state along the upper base surface la, and the upper electrostatic chuck 2 attached to the upper holding surface la; The lower electrostatic chuck 2 mounted on the lower base surface la 'is electrostatically attracted and held.

Thereafter, the upper and lower holding plates 1, 1 ′ are moved closer to each other by the operation of the lifting means as shown by the two-dot chain line in FIG. 5A to form a vacuum chamber S, and the inside of the vacuum chamber S is predetermined. After reaching the vacuum degree, the upper and lower holding plates 1, \ 'are adjusted and moved relative to each other in the ΘΘ direction, and the upper and lower substrates A and B are aligned.

[0047] After completion of this alignment operation, the upper substrate A is electrostatically connected to the electrostatic chuck 2 above the upper base surface la by the operation of the separating means 4 as shown in FIG. 5 (b). The upper substrate A is moved toward the lower substrate B by being separated while being adsorbed.

As a result, 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.

[0048] In this superposition process, gas or fluid enters between the upper and lower substrates A and B. It can be completely prevented, and the thin plate or thin film electrostatic chuck 2 on the upper substrate A, which has extremely low rigidity, serves as a cushioning material. Even if a slight non-uniformity occurs, there is an advantage that the annular adhesive C formed between the upper and lower substrates A and B is hardly affected by a spacer (not shown).

[0049] 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 chucking function is stopped.

After that, the inside of the vacuum chamber S is returned to the atmospheric pressure, and the pressure is evenly applied by the pressure difference generated inside and outside of both the substrates A and B. The pressure difference generated inside and outside the both substrates A and B reaches the predetermined gap. The bonding process is completed by crushing.

Subsequently, the upper substrate A bonded to the lower substrate B through the annular adhesive C as shown in FIG. 5 (c) is moved upward by the operation of the adhering means 3 and the suction adsorbing means 5. The electrostatic chuck 2 is pulled toward the upper base surface la, and separation of both of them starts.

[0051] At this time, the residual attracting 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 come in contact with each other, and may be difficult to peel off.

[0052] Therefore, as described above, the entire surface of the upper electrostatic chuck 2 from the surface of the upper substrate A is not separated at the same time, but partially from the portion facing the outer peripheral end A1 of the bonded upper substrate A. If it is deformed and a gap for peeling is partially formed between the outer peripheral edge A1 of the upper substrate A, the electrostatic chucking portion 2a of the electrostatic chuck 2 and the surface of the upper substrate A are separated. Since the residual gap is forcibly attenuated and disappears, the electrostatic force on the electrostatic chuck 2 of the upper electrostatic chuck 2 is peeled off smoothly from the surface of the 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.

[0053] Further, the upper electrostatic chuck 2 peeled from the surface of the upper substrate A adheres to the upper base surface la, and thereafter, the upper and lower holding plates 1, 1 'are separated from each other by the operation of the elevating means. Move in the direction to return to the initial state.

[0054] The surroundings of the upper and lower substrates A and B that have been bonded together in this situation are in the atmosphere or 100 It is in a low vacuum of Pa or more. In this atmosphere, if necessary, the lower holding plate as shown in Fig. 6 (a) and (b): As the separating means 7, the lift pin is raised from the base surface la ′ and the plurality of through holes 6 opened in the lower electrostatic chuck 2, or a gas such as nitrogen gas or air or other fluid is moved upward. The upper and lower substrates A and B that have been bonded together are also pushed up by the surface force of the lower electrostatic chuck 2 to the lower surface B 1 of the lower substrate B. A static elimination gap S2 is formed.

[0055] 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 attached to the lower substrate B made of glass. An electric field (specifically, an alternating electric field) that neutralizes the charge remaining on the upper and lower substrates A and B is induced by the peeling electrification that occurs at the moment of peeling from the existing state.

As a result, in this induced electric field part, a part of the 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 generated charge.

[0056] 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 la and the lower substrate attached to the lower base surface la '. There is a possibility that glass cullet (shards) may get into the electrostatic chuck 2 when it is set.

In this case, the surface of the electrostatic chuck 2 such as the dielectric 2a is obtained by interposing the cullet between the electrostatic chucks 2 along with the electrostatic adsorption between the upper and lower substrates A and B. May break down and break down.

[0057] Even in such a case, the electrostatic chuck 2 in the form of a thin plate or thin film is detachably provided on the upper and lower base surfaces la and W, so that these electrostatic chucks 2 can be easily replaced. There is also an advantage in that maintenance is excellent.

[0058] It should be noted that the electrostatic chuck apparatus D force work A and B 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 workpieces A and B. However, the present invention is not limited to this. However, the present invention is not limited to this, and it is provided in a board assembly apparatus other than this board bonding machine, a board transfer apparatus that transfers boards, For LCD panel It is possible to hold a substrate other than the glass substrate.

Furthermore, although the substrate bonding machine for bonding two substrates A and B in a vacuum has been described, the present invention is not limited to this, and a substrate bonding machine for bonding substrates A and B in the atmosphere can be used. The same effects as the above-described vacuum bonding machine can be obtained.

[0059] In the illustrated example, the force that supports the electrostatic chuck 2 so as to reciprocate in the vertical direction only with respect to the upper base surface la of the upper holding plate 1 is not limited to this. The electrostatic chuck 2 is supported so as to be movable in the Z direction with respect to the lower base surface la ′, and the lower holding plate is further provided with an adhesion means 3 and an isolation means 4, and the adhesion means 3 The electrostatic chuck 2 is attached to the lower base surface 1 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 each other as described above. The lower holding plate 1 is separated to 1 'force release position in 4 and moved in parallel.At the same time, the electrostatic chucking function of this electrostatic chuck 2 is stopped. The substrate A and B may be bonded together by peeling back the surface force electrostatic chuck 2 of the lower substrate B that has been moved backward to the lower holding plate. .

Brief Description of Drawings

FIG. 1 is a longitudinal front view showing Embodiment 1 of a workpiece transfer method and an electrostatic chuck device of the present invention, and (a) and (b) show in order of operation steps.

FIG. 2 is a reduced bottom view taken along line (2)-(2) in FIG. 1 (a).

FIG. 3 is a reduced and enlarged plan view taken along line (3)-(3) in FIG. 1 (a).

FIG. 4 is a longitudinal sectional front view showing Embodiment 2 of the workpiece transfer method and electrostatic chuck apparatus of the present invention, and (a) and (b) show in order of operation steps.

FIG. 5 is a reduced longitudinal front view showing Example 3 of a bonding machine using the workpiece transfer method and the electrostatic chuck device of the present invention, and (a) to (c) show the substrate bonding method in the order of steps. It is shown.

[FIG. 6] A reduced longitudinal front view showing the state of static elimination, (a) and (b) are shown in order of operation steps. Explanation of symbols

[0061] A Workpiece (upper board) A1 Outer edge

B Workpiece (lower substrate) C Ring adhesive D Electrostatic chuck device S Vacuum chamber

SI peeling gap S2 static elimination gap 1 Upper holding plate la Base surface 1 'Lower holding plate la' Base surface 2 Electrostatic chuck 2a Electrostatic chuck 2b Dielectric 2c Electrode

2d Outer end 2e Stator

2f Current supply part 2g

3 Adhering means 3a Magnetic

3b Magnetic body (magnet) 4 Separation means 4a Pass through 4b Sealed space 5 Suction adsorption means 6 Through hole

7 Separation means

Claims

The scope of the claims

[1] 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 an attaching means for pulling the electrostatic chuck to the holding plate so as to be detachable, and an isolating means for separating the electrostatic chuck from the holding plate. The attaching means electrostatically attaches the holding plate to the holding plate. The chuck is attached, and the workpiece is attracted and held by the attached electrostatic chuck, and the electrostatic chuck function of the electrostatic chuck is separated by holding the electrostatic chuck and the workpiece together by the separating means. A workpiece transfer method characterized in that after being stopped, only the electrostatic chuck is reattached to the holding plate by the attaching means so that the workpiece is left in the open position.

[2] The method of transferring a workpiece 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 the smooth base surface of the holding plate having a rigid body force. Law.

[3] The electrostatic chucking portion of the electrostatic chuck is also partially deformed at a location facing the outer peripheral end of the workpiece, and a separation gap is partially formed between the outer peripheral end of the workpiece. The workpiece transfer method according to claim 1 or 2.

[4] An electrostatic chuck device comprising a holding plate and an electrostatic chuck that holds the workpiece by suction, and supports the electrostatic chuck in a direction that intersects with the workpiece side surface of the holding plate. Then, with the electrostatic chuck placed along the workpiece side surface, the surface of the workpiece is electrostatically attracted, and the electrostatic chuck is moved to the open position while the workpiece is electrostatically attracted. At the same time, the electrostatic chuck function of the electrostatic chuck is stopped, and only the electrostatic chuck is moved backward from the open position toward the chuck position. An electrostatic chuck device, wherein the chuck is peeled off.

[5] The electrostatic chuck device according to claim 4 is provided on one or both of the pair of holding plates, and the two substrates as the workpiece are opposed to each other and held detachably between the holding plates. The electrostatic chuck of the electrostatic chuck device is separated from either one of the holding plates while the one substrate is electrostatically attracted, and the one substrate is moved toward the other substrate, and both the substrates are moved by the annular adhesive. A substrate bonding method characterized in that substrates are bonded together.