JP6086476B2 - Substrate floating device - Google Patents

Description

  The present invention relates to a substrate levitating apparatus that ejects a gas such as compressed air to levitate a substrate.

  A flat panel display such as a liquid crystal display or a plasma display uses a substrate coated with a resist solution (referred to as a coated substrate). The coated substrate is formed by a coating apparatus that uniformly coats a coating solution such as a resist solution or a chemical solution on the substrate.

  A schematic diagram of an example of a coating apparatus is shown in FIG. The coating device 80 includes a transport device 81 that transports the substrate W and a coating unit 82 that coats the substrate with a coating liquid. The coating unit 82 includes a base having a slit extending in a direction perpendicular to the direction of transport of the substrate W by the transport device 81, and discharges the coating liquid from the slit while transporting the substrate W at a predetermined speed. A coating film is formed.

  Particularly in recent years, there is a case where the substrate W is transported in a non-contact state by using a substrate floating device that ejects gas to the transport device 81 and floats the substrate W with the pressure.

  An example of this substrate floating apparatus is shown in FIG. In this substrate levitation apparatus 90, the gas is supplied from the gas supply means 94 to the jet outlet 93 on the surface of the substrate levitation apparatus 90 via the manifold 91 and the branch pipe 92, and the gas is ejected from the jet outlet 93. Then, the substrate W is levitated.

  The substrate levitation apparatus 90 also has a suction port 97 on the surface, and when the substrate W is floated, a suction force is supplied from the suction force supply means 98 to the suction port 97 via the manifold 95 and the branch pipe 96. . In this way, the substrate W is deflected as compared with the case where the substrate W is floated by only ejecting gas by ejecting the gas from the ejection port 93 and simultaneously sucking the substrate W from each suction port 97. And the flatness can be maintained, and the flying height of the substrate W can be precisely controlled. It is effective for forming a coating film on the substrate W in the coating unit 82 to provide the ejection port 93 and the suction port 97 in the substrate levitation apparatus 90 and to precisely control the flying height by the balance between gas ejection and suction. Technology.

JP 2009-59823 A

  However, the substrate floating apparatus described in Patent Document 1 and FIG. 8 has a problem that the flying height of the substrate may become unstable over time. Specifically, as shown in FIG. 8, when foreign matter 99 such as particles or small fragments of the substrate W exists around the substrate floating device 90, the foreign matter may be sucked from the suction port 97. If the foreign matter 99 is sucked in this way, it may be deposited on the manifold 95 or caught on the branch pipe 96. In particular, if the branch pipe 96 is caught, the branch pipe 96 is clogged, and suction from the suction port 97 communicating with the branch pipe 96 becomes insufficient, so that the flying height of the substrate W is kept constant. Can not be.

  Here, in the coating apparatus as shown in FIG. 7, in order to uniformly apply the coating liquid from the coating unit 82 to the substrate W as described above, the distance between the coating unit 82 and the substrate W is kept constant. It is important to keep the flying height of the substrate W constant. If the flying height of the substrate W becomes unstable as described above, there is a possibility that uneven coating occurs.

  Furthermore, there is a possibility that the substrate W and the substrate floating device 90 may come into contact with each other, which may damage the back surface of the substrate W or cause static electricity on the substrate W to cause adhesion of foreign matters or destruction of internal circuits. .

  The present invention has been made in view of the above-described problems of the prior art, and provides a substrate levitating device that can prevent clogging of piping and can always levitate a substrate at a constant levitating height. It is an object.

In order to solve the above problems, a substrate levitation apparatus of the present invention has a floating surface having a plurality of first vent holes for ejecting or sucking gas and a plurality of second vent holes for sucking or ejecting gas. A substrate levitation apparatus that includes a plate and levitates a substrate upward by performing gas ejection and suction from the first vent and the second vent, and the first levitation when the substrate is levitated The operations of the vent and the second vent are switched every predetermined time. When the first vent is ejecting gas, the second vent sucks gas, and the first vent vents the gas. The second vent vents a gas when the air is sucked, and the gas vent is exclusively blown outside the group of the first vent and the second vent in the substrate transport direction. It is characterized in that the third ejection port to perform is provided .

  According to the substrate levitation apparatus, the operations of the first vent and the second vent when the substrate is levitated are switched every predetermined time, so that the foreign matter sucked together when the gas is sucked is removed from the gas. Since it can blow out when it switches to the operation | movement which ejects, it is possible to prevent clogging of a floating board.

  The first vent and the second vent have the same shape, and are arranged on the upper surface of the floating plate so that the first vent and the second vent are adjacent to each other. Good to have been.

  By doing so, it is possible to prevent the floating state of the substrate from changing when the ejection and suction operations of each vent are switched.

  Moreover, it is good to have further the cleaning part which removes the foreign material on the upper surface of the said floating board regularly.

  By doing so, it is possible to prevent foreign matter blown out from the first vent and the second vent from continuing to stay on the upper surface of the floating plate.

  According to the substrate levitation apparatus of the present invention, it is possible to prevent clogging of piping and to always float the substrate at a constant levitation height.

It is the schematic of the board | substrate floating apparatus in one Embodiment of this invention. It is the schematic at the time of switching operation | movement of each ventilation port. It is an example of arrangement | positioning of each ventilation port. It is the schematic of the cleaning method of the substrate floating apparatus of this embodiment. It is the schematic of the substrate floating apparatus in other embodiment. It is the schematic of the substrate floating apparatus in other embodiment. It is the schematic of the coating device which has a board | substrate floating apparatus. It is the schematic of the conventional board | substrate floating apparatus.

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

  A substrate floating apparatus according to an embodiment of the present invention is shown in FIG. The substrate levitation apparatus 1 has a levitation stage 2, and the levitation stage 2 ejects gas to levitate the substrate W. In addition, the levitation stage 2 performs gas suction at the same time, and balances the ejection and suction of the gas to make the flying height uniform over the entire surface of the substrate W.

  The levitation stage 2 has a levitation plate 10, a gas supply source 17, and a suction power supply source 20. When the gas is supplied from the gas supply source 17, the levitation plate 10 ejects gas from its upper surface. Further, when the suction force is supplied from the suction force supply source 20, the levitation plate 10 sucks gas from the upper surface thereof.

  The floating plate 10 is a block having a flat upper surface, and has a first manifold 13 and a second manifold 15 inside. The upper surface of the floating plate 10 has a plurality of first vent holes 11 communicating with the first manifold 13 and a plurality of second vent holes 12 communicating with the second manifold 15. Each first vent 11 communicates with the first manifold 13 via the first branch pipe 14, and each second vent 12 connects the second manifold 15 and the second branch pipe 16. Communicated through.

  The first manifold 13 is a tubular object provided inside the floating plate 10, and has a connection port connected to each first branch pipe 14 on the tube wall. The first manifold 13 is also connected to the gas supply source 17 and the suction force supply source 20 via a pipe, and has a connection port therefor. Note that the first manifold 13 is airtight at portions other than these connection ports.

  The second manifold 15 is a tubular member provided inside the floating plate 10, and has a connection port connected to each second branch pipe 16 on the tube wall. The second manifold 15 is also connected to the gas supply source 17 and the suction force supply source 20 via a pipe, and has a connection port therefor. Note that the second manifold 15 is airtight at portions other than these connection ports.

  The gas supply source 17 is a supply source that supplies dry air, N2, and the like, and examples thereof include factory compressed air. The gas supply source 17 is connected to the first manifold 13 and the second manifold 15 through the piping as described above.

  A three-way valve 18 is provided between the gas supply source 17 and the first manifold 13 and the second manifold 15, and the three-way valve 18 communicates the gas supply source 17 and the first manifold 13. The gas supply source 17 and the second manifold 15 are cut off, the gas is supplied only to the first manifold 13, and this gas passes through the first branch pipe 14, It is ejected from the first vent 11.

  On the contrary, when the three-way valve 18 is in a state where the gas supply source 17 and the second manifold 15 are in communication, the gas supply source 17 and the first manifold 13 are shut off, and the gas Is supplied only to the second manifold 15, and this gas is ejected from the second vent 12 through the second branch pipe 16.

  An open / close valve 19 is provided in the pipe between the gas supply source 17 and the three-way valve 18. When the open / close valve 19 is in a closed state, the supply of gas to the three-way valve 18 is interrupted, so that no gas is supplied to the first manifold 13 or the second manifold 15.

  In the drawings after FIG. 1, a route communicating in the three-way valve is shown without filling, and a blocked route is shown with filling. For example, in FIG. 1, the three-way valve 18 is set to communicate the gas supply source 17 and the first manifold 13. As for the open / close valve, the open / close valve in the open state is shown without being filled, and the open / close valve in the closed state is shown as being filled. For example, the open / close valve 19 in FIG. 1 is in an open state.

  The suction force supply source 20 is an exhaust device such as a vacuum pump or a blower, and performs exhaust with a constant output. The first manifold 13 and the second manifold 15 are connected via a pipe.

  A three-way valve 21 is provided between the suction force supply source 20 and the first manifold 13 and the second manifold 15, and the three-way valve 21 communicates the suction force supply source 20 and the first manifold 13. In this state, the suction force supply source 20 and the second manifold 15 are shut off, and the suction force is supplied only to the first manifold 13, and the first suction via the branch pipe 14. Gas is sucked from the vent 11.

  On the contrary, when the three-way valve 21 is in a state where the suction force supply source 20 and the second manifold 15 are in communication, the suction force supply source 20 and the first manifold 13 are shut off. The suction force is supplied only to the second manifold 15, and the gas is sucked from the second vent 12 via the second branch pipe 16.

  An open / close valve 22 is provided in the pipe between the suction force supply source 20 and the three-way valve 21. When the on-off valve 22 is in a closed state, the supply of gas to the three-way valve 21 is interrupted, so that no gas is sucked from the first manifold 13 or the second manifold 15.

  In the substrate levitation apparatus 1 having such a configuration, the three-way valve 18 is in a state where the gas supply source 17 and the first manifold 13 are communicated as shown in FIG. 1, and the three-way valve 21 is the suction force supply source 20. And the second manifold 15 are in communication with each other, gas is ejected from the first vent 11 and gas is sucked from the second vent 12. Thus, by performing a balance between gas ejection and gas suction from the upper surface of the levitation stage 2, the substrate W transported to the substrate levitation apparatus 1 is levitated above the levitation stage 2, and further the substrate W It is possible to make the flying height uniform over the entire surface.

  However, if the gas is continuously ejected and sucked in this way, foreign matter 3 such as particles and small fragments of the substrate W are also sucked from the second vent hole, and the second branch pipe 16 may be clogged. There is.

  FIG. 2 is a schematic diagram showing a state in which the operation of each vent is switched with respect to FIG.

  In FIG. 1, the three-way valve 18 is in a state where the gas supply source 17 and the first manifold 13 are communicated, and the three-way valve 21 is in a state where the suction force supply source 20 and the second manifold 15 are in communication. However, in FIG. 2, the three-way valve 18 is switched from that state so that the gas supply source 17 and the second manifold 15 communicate with each other, and at the same time, the three-way valve 21 is switched to the suction force supply source 20. The state is switched to the state in which the first manifold 13 is communicated.

  By switching the paths of the three-way valve 18 and the three-way valve 21 in this way, the gas is sucked from the first vent port 11 from which the gas was jetted in the example of FIG. 1, and in the example of FIG. The gas comes to be ejected from the second vent hole 12 that has been sucked. That is, the operations of the first vent 11 and the second vent 12 are switched.

  By switching the operations of the first vent 11 and the second vent 12 in this manner, the operation of the foreign matter 3 accumulated in the branch pipe 16 communicating with the second vent 12 before the operation is switched is switched. After that, it is blown up by the gas supplied to the branch pipe 16 and discharged from the levitation stage 2, so that the clogging of the branch pipe 16 is eliminated.

  Then, the switching of the operation of the first vent hole 11 and the second vent hole 12 is performed every predetermined time, so that the foreign matter 3 continues to accumulate in the first branch pipe 14 and the second branch pipe 16. Therefore, clogging of piping is prevented.

  The predetermined time may be set every time, for example, every time one substrate W is transferred, or every time ten substrates W are transferred, and can be set arbitrarily.

  FIG. 3 is an example of the arrangement of the vents.

  As shown in FIGS. 1 and 2, the operation of the first vent 11 and the second vent 12 is switched, so that clogging of the pipe is prevented as described above. However, if the arrangement of the first vent hole 11 and the second vent hole 12 is uneven, the flying height of the substrate W may be different before and after the operation is switched, or the substrate W may be tilted and floated. is there. If the floating state of the substrate W changes before and after the switching of the operation in this way, an operation that requires accuracy in the flying height of the substrate W, such as application of the coating liquid to the floating substrate W, is performed. It is difficult to implement.

  Therefore, it is desirable that the first vent hole 11 and the second vent hole 12 be arranged without any deviation. Specifically, as shown in FIG. 3A, the first vent hole 11 and the second vent hole 12 are arranged. The first vents are arranged so that the vents 12 are alternately arranged, or the first vents 11 and the second vents 12 are respectively arranged on the staggered pattern as shown in FIG. It is desirable that 11 and the second vent 12 are arranged on the floating stage 2 so as to be adjacent to each other.

  Further, for example, when the first vent hole 11 and the second vent hole 12 have the same shape, the pressure loss when the gas is ejected or sucked from the first vent hole 11 and the second vent hole. The pressure loss when the gas is ejected or sucked from 12 is substantially the same as the fact that the floating state of the substrate W changes before and after the operation of the first vent 11 and the second vent 12 is switched. It is desirable to prevent.

  FIG. 4 is a schematic view showing a cleaning method of the substrate floating apparatus in the present embodiment.

  The foreign matter 3 blown out from the first vent 11 and the second vent 12 by switching the operation of the first vent 11 and the second vent 12 continues to fall on the upper surface of the levitation stage 2 and stay. There is a fear.

  Therefore, in this embodiment, the cleaning unit 30 is placed on the upper surface of the levitation stage 2 while the substrate W is not levitated above the levitation stage 2, and the gas near the upper surface of the levitation stage 2 is sucked. As a result, the foreign matter 3 on the upper surface of the levitation stage 2 is collected by the cleaning unit 30 and the upper surface of the levitation stage 2 is cleaned.

  The cleaning unit 30 includes a top plate 31 and a plurality of side plates 32. The top plate 31 and the side plates 32 are combined and have a box shape having an opening below. When the cleaning unit 30 is placed on the upper surface of the levitation stage 2, each side plate 32 is in contact with the upper surface of the levitation stage 2 to form a closed space between the cleaning unit 30 and the upper surface of the levitation stage 2. Further, a packing or the like is provided on a portion of the side plate 32 that contacts the levitation stage 2, and is sealed when it contacts the levitation stage 2.

  In addition, the cleaning unit 30 has a size that covers almost the entire upper surface of the levitation stage 2 so that it can be sucked regardless of the position of the foreign matter 3 on the upper surface of the levitation stage 2. Yes.

  The cleaning unit 30 is provided with a suction pipe 33. The suction pipe 33 is connected to a suction force supply means (not shown), and the suction force supply means operates to pass through the suction pipe 33. The gas in the closed space formed by the cleaning unit 30 and the upper surface of the levitation stage 2 is sucked.

  After the cleaning unit 30 having such a configuration is placed on the upper surface of the levitation stage 2, the gas in the closed space formed by the cleaning unit 30 and the upper surface of the levitation stage 2 is sucked, so that the levitation stage as described above. The foreign matter that has fallen on the upper surface of 2 is collected by the cleaning unit 30 and the upper surface of the levitation stage 2 is cleaned.

  Moreover, in this embodiment, although the upper surface of the levitation stage 2 is cleaned by such a cleaning unit 30, the upper surface of the levitation stage 2 may be cleaned by other forms. For example, an adhesive sheet may be placed on the upper surface of the levitation stage 2. Cleaning may be performed by spreading the foreign matter 3 on the adhesive sheet.

  FIG. 5 is a schematic view of a substrate floating apparatus according to another embodiment.

  In the present embodiment shown in FIG. 1, a three-way valve 18 is provided between the gas supply source 17 and the first manifold 13 and the second manifold 15, and the suction force supply source 20 and the second manifold 15 are provided. A three-way valve 21 is provided between the first manifold 13 and the second manifold 15, but in the embodiment of FIG. 5, instead, between the gas supply source 17 and the first manifold 13. Has an open / close valve 41, and an open / close valve 42 is provided between the gas supply source 17 and the second manifold 15. An opening / closing valve 43 is provided between the suction force supply source 20 and the first manifold 13, and an opening / closing valve 44 is provided between the suction force supply source 20 and the second manifold 15.

  In FIG. 5, the opening / closing valve 41 and the opening / closing valve 44 are in an open state, and the opening / closing valve 42 and the opening / closing valve 43 are in a closed state. In this state, since the gas from the gas supply source 17 is supplied to the first manifold 13, the gas is ejected from the first vent 11. Further, since the suction force from the suction force supply source 20 is supplied to the second manifold 15, the gas is sucked from the second vent 12.

  Although not shown, the opening / closing valve 41 and the opening / closing valve 44 are switched from the open state to the closed state, and the opening / closing valve 42 and the opening / closing valve 43 are switched from the closed state to the open state, whereby the first ventilation Gas is sucked from the mouth, and gas is ejected from the second vent. That is, the operations of the first vent 11 and the second vent 12 are switched.

  In this embodiment, it is necessary to operate the four on-off valves 41 to 44 in switching the operation of the first vent 11 and the second vent 12. However, in the embodiment shown in FIG. In contrast, it is possible to make a state in which gas is ejected from both the first vent 11 and the second vent 12. In addition, it is possible to make a state in which gas is sucked from both the first vent 11 and the second vent 12.

  Then, after the gas is ejected from both the first vent 11 and the second vent 12, the upper surface of the levitation stage 2 is cleaned by the cleaning unit 30 shown in FIG. It is possible to perform cleaning while preventing 3 from entering the first vent hole 11 or the second vent hole 12 by mistake.

  FIG. 6 shows a substrate floating apparatus according to still another embodiment. FIG. 6A is a schematic diagram of the substrate floating apparatus according to this embodiment, and FIG. 6B shows the state of the end portion of the substrate when this embodiment is not used.

  In the embodiment shown in FIG. 6A, the jet outlet 51 is provided outside the first vent 11 and the second vent 12 on the levitation stage 2, and the substrate W is placed on the levitation stage 2. While ascending, the gas is always blown out without switching the operation.

  The spout 51 is an opening provided on the upper surface of the levitation stage 2, similarly to the first vent 11 and the second vent 12. The ejection port 51 is connected to the gas supply source 52 via a pipe, and gas is ejected from the ejection port 51 by supplying gas from the gas supply source 52.

  Further, in the embodiment shown in FIG. 6, the gas supply source 52 is provided separately from the gas supply source 17, but the piping is branched between the three-way valve 18 and the opening / closing valve 19 and connected to each jet outlet 51. Accordingly, the gas supply source 17 may also supply gas to the ejection port 51.

  Here, if the nozzle 51 is not provided as in FIG. 1 or the like, there is a time when the outermost vent on the upper surface of the levitation stage 2 operates to suck gas.

  Here, for example, when the substrate W on the substrate levitation apparatus 1 is transported in the X-axis direction, the end portion of the substrate W passes through the region where the first vent hole 11 and the second vent hole 12 exist. At this time, the substrate W is finally pulled by suction. Therefore, the edge part of the board | substrate W becomes a form which hangs down as shown in FIG.6 (b). If the substrate W is transported in the X-axis direction in this state, the end of the substrate W may interfere with an apparatus adjacent to the substrate floating apparatus 1.

  Therefore, by providing the ejection port 51 so that the gas is always ejected at the outermost side in the transporting direction of the substrate W on the floating stage 2 and the end portion of the substrate W faces upward, the above-described interference may occur. It can be eliminated.

  The substrate levitation apparatus described above can prevent the suction side path from being clogged, and can always levitate the substrate at a constant flying height.

DESCRIPTION OF SYMBOLS 1 Board | substrate levitation | floating apparatus 2 Levitation stage 3 Foreign material 10 Levitation board 11 1st ventilation port 12 2nd ventilation port 13 1st manifold 14 1st branch piping 15 2nd manifold 16 2nd branch piping 17 Gas supply source DESCRIPTION OF SYMBOLS 18 Three-way valve 19 Open / close valve 20 Suction power supply source 21 Three-way valve 22 Open / close valve 30 Cleaning part 31 Top plate 32 Side plate 33 Suction piping 41 Open / close valve 42 Open / close valve 43 Open / close valve 44 Open / close valve 51 Jet outlet 52 Gas supply source 80 Coating device DESCRIPTION OF SYMBOLS 81 Conveying device 82 Application | coating part 90 Substrate floating device 91 Manifold 92 Branch piping 93 Outlet 94 Gas supply means 95 Manifold 96 Branch piping 97 Suction port 98 Suction force supply means 99 Foreign material W Substrate

Claims (3)

A plurality of first vents for jetting or sucking gas;
A plurality of second vents for sucking or ejecting gas;
With a floating plate on the upper surface,
A substrate levitating apparatus for levitating a substrate upward by performing gas ejection and suction from the first vent hole and the second vent hole;
The operations of the first vent and the second vent when the substrate is levitated are switched every predetermined time. When the first vent is ejecting gas, the second vent vents the gas. When the first vent hole sucks the gas, the second vent hole jets the gas, and the group of the first vent hole and the second vent hole in the substrate transport direction. A substrate levitation apparatus characterized in that a third ejection port for exclusively ejecting gas is provided outside of the substrate.   The first vent and the second vent have the same shape, and are arranged on the upper surface of the floating plate so that the first vent and the second vent are adjacent to each other. The substrate floating apparatus according to claim 1, wherein:   The substrate floating apparatus according to claim 1, further comprising a cleaning unit that periodically removes foreign matter on the upper surface of the floating plate.

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