JP6180245B2 - Cleaning device - Google Patents

Description

  The present invention relates to a cleaning device for cleaning a substrate floating device that floats a substrate by ultrasonic vibration.

  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 produced by forming a coating film by uniformly applying a resist solution on the substrate by a coating apparatus, and then drying the coating film by a heat treatment apparatus.

  As one type of this heat treatment apparatus, for example, there is a floating conveyance heat treatment apparatus as shown in Patent Document 1 and FIG. As shown in FIG. 4, the levitation transfer heat treatment apparatus 90 includes a substrate levitation apparatus 91 including a vibration plate 92 and an ultrasonic wave generation unit 93, and a heating device 94 that heats the vibration plate 92, and is heated by the heating device 94. The substrate levitation device 91 allows the substrate W to be heated in a non-contact manner by levitation of the substrate W by ultrasonic vibration.

JP 2012-248755 A

  If such a levitation transfer heat treatment apparatus 90 is continuously used, foreign matter 95 such as particles and fine pieces of glass are generated in the movable part and sliding part in the apparatus, blown from the surrounding environment, or carried in. There is a possibility of falling on the diaphragm 92 due to adhesion to the substrate W. If the foreign matter 95 remains on the diaphragm 92, it adheres to the back surface of another substrate W. Then, foreign matter is mixed into the final product using the substrate W, or the vibration of the vibration plate 92 is transmitted to the substrate W through the foreign matter 95, so that the floating amount of the substrate W is changed and drying unevenness occurs. There is a possibility that the diaphragm 92 may be damaged by dragging the foreign matter 95. In particular, when the vibration plate 92 is scratched, there is a possibility that drying unevenness may occur so that the shape of the scratch is transferred to the coating film on the substrate W.

  In order to prevent these problems from occurring, it is necessary to periodically clean the surface of the diaphragm 92 so that the foreign matter 95 does not exist on the diaphragm 92. Conventionally, this cleaning has been performed by wiping off the foreign matter 95 using a waste cloth, but in this case, the foreign matter 95 may be rubbed against the diaphragm 92 when the foreign matter 95 is wiped off. If the foreign material 95 is rubbed against the diaphragm 92 in this way, there is a problem that the diaphragm 92 is damaged, and thereafter, the coating film on the substrate W is unevenly dried.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a cleaning device that can remove foreign matter without damaging a cleaning object.

  In order to solve the above problems, a cleaning device of the present invention has a flat bottom surface facing a cleaning object, and a pad portion that floats on the cleaning object by ultrasonic vibration of the cleaning object; and the pad A cover portion that covers the upper surface and the side surface of the pad portion with a gap between the upper surface of the pad portion and the side surface of the pad portion, and is connected to the cover portion, and the pad portion and the cover portion A suction means for sucking the gas in the gap, and an opening is formed between the lower end portion of the cover portion and the side surface of the pad portion, and the lower end portion is positioned higher than the bottom surface of the pad portion. It is characterized by that.

  According to the cleaning device, it is possible to remove foreign substances without damaging the object to be cleaned. Specifically, by having a pad portion that floats on the cleaning object by ultrasonic vibration of the cleaning object, foreign matter on the cleaning object can be sucked and removed in a non-contact state with the cleaning object. It is possible to remove foreign substances without damaging the object to be cleaned. In addition, an opening is formed between the lower end portion of the cover portion and the side surface of the pad portion, and the lower end portion is positioned higher than the bottom surface of the pad portion, so that the dimension is larger than the flying height of the pad portion. The foreign matter can also be sucked and removed by sucking it into the gap between the pad portion and the cover portion.

  Further, the pad portion has a through hole penetrating the upper surface or side surface and bottom surface of the pad portion, and the suction means may suck gas near the bottom surface of the pad portion through the through hole. .

  In this way, foreign substances located immediately below the bottom surface of the pad portion can be removed by suction, and an adsorption force is generated between the object to be cleaned and the pad portion. Therefore, it is possible to give an appropriate resistance against movement in a direction parallel to the bottom surface of the pad portion.

  According to the cleaning device of the present invention, foreign matter can be removed without damaging the object to be cleaned.

It is the schematic of the cleaning apparatus in one Embodiment of this invention. It is the schematic of the cleaning apparatus in one Embodiment of this invention. It is the schematic which shows the cleaning form by the cleaning apparatus in this embodiment. It is the schematic which shows a levitation conveyance heat processing apparatus.

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

  1 and 2 are schematic views of a cleaning device according to an embodiment of the present invention, FIG. 1 is a schematic view showing a form of cleaning by the cleaning device, and FIG. 2 (a) is a top view of the cleaning device. FIG. 2B is a front view of the cleaning device.

  The cleaning device 1 includes a pad portion 2, a cover portion 3, and suction means 4, and cleans the surface of a diaphragm (cleaning target) 92 included in the substrate floating device 91 in the floating conveyance heat treatment device 90.

  Here, the levitation transfer heat treatment apparatus 90 is used in a process of drying the substrate on which the coating liquid has been applied. In that process, the vibration plate 92 ultrasonically oscillates the substrate W to levitate the substrate W, and this In the state, the substrate is heated and dried.

  When the cleaning device 91 cleans the vibration plate 92, the vibration plate 92 is ultrasonically vibrated, and the pad portion 2 and the cover portion 3 are floated by ultrasonic vibration. While moving on the diaphragm 92 as indicated by the arrow, the surface of the diaphragm 92 (the surface facing the cleaning device 1) is cleaned. In addition, a gap is provided between the pad portion 2 and the cover portion 3, and when the suction means 4 sucks the gas in the gap, the foreign matter on the diaphragm 92 is sucked into the gap and is cleaned. The surface of the diaphragm 92 is cleaned.

  In the following description, one direction in the horizontal direction is the X-axis direction, the direction orthogonal to the X-axis direction on the horizontal plane is the Y-axis direction, the direction orthogonal to both the X-axis direction and the Y-axis direction, that is, the vertical direction. The Z axis direction.

  The pad portion 2 is a cylindrical object in the present embodiment, and the bottom surface 11 faces the diaphragm 92 that is an object to be cleaned.

  Here, as described above, the cleaning by the cleaning device 1 is performed under the state where the pad portion 2 is floated by the ultrasonic vibration of the diaphragm 92.

  In this case, the pad portion 2 floats when the bottom surface 11 of the pad portion 2 receives the radiated sound pressure emitted from the vibration plate 92 that is ultrasonically vibrated by the ultrasonic generator 93, but the pad portion 2 stably floats. For this purpose, it is necessary to receive the radiation sound pressure evenly over the entire bottom surface 11. For this purpose, the bottom surface 11 is a flat surface, and the distance from the diaphragm needs to be uniform over the entire bottom surface 11.

  In addition, since the diaphragm 92 is heated to 120 ° C. to 140 ° C. by the heating device 94 and used, the material of the pad portion 2 has a heat resistant temperature so that the cleaning operation can be performed even in such a heated state. High and low thermal conductivity are desirable. Further, if the pad portion 2 warps due to the temperature rise of the pad portion 2 and the flatness of the bottom surface 11 is lost, it becomes difficult for the pad portion 2 to stably float and oscillate. It is desirable that the linear expansion coefficient is low and the warp is difficult. Considering these characteristics, the material of the pad portion 2 is most preferably a fluororesin. In addition, since the fluororesin is soft and has a small coefficient of friction, there is no possibility that the diaphragm is damaged even if the pad portion 2 contacts the diaphragm.

  Further, on the upper surface of the pad portion 2, a mechanism (attachment hole or the like) for attaching a connecting member 23 for connecting the pad portion 2 and the cover portion 3 is provided on a concentric circle.

  In the present embodiment, the pad portion 2 is provided with a through hole 12 that penetrates the top surface and the bottom surface 11. Thereby, when the suction force is working near the upper surface of the pad portion 2, the suction force works also near the bottom surface 11 through the through hole 12. The through hole 12 may penetrate the side surface and the bottom surface 11 of the pad portion 2. In this case, when a suction force is acting in the vicinity of the side surface of the pad portion 2, the suction force also acts in the vicinity of the bottom surface 11 through the through hole 12.

  The cover unit 3 includes a top plate 21, a side plate 22, and a pipe connection port 25, and includes a gap 24 between the upper surface of the pad unit 2 and the side surface of the pad unit 2, while The upper surface and side surfaces of the pad portion 2 are covered so as to cover from above. By this cover portion 3, the gap 24 is in a state of communicating with the outside air only at the opening portion of the pipe connection port 25, the opening portion 28 formed between the side plate 22 and the pad portion 2, and the through hole 12. Yes.

  The top plate 21 is a disk-like plate-like body having a through hole having a diameter substantially the same as the diameter of the opening of the pipe connection port 25 described later in this embodiment, and the outer diameter of the top plate 21 is a pad. It is larger than the diameter of the part 2. In addition, stainless steel etc. are used for the member which comprises the cover part 3 including the top plate 21, for example.

  Further, on the lower surface of the top plate 21, a mechanism (mounting hole or the like) for attaching the connecting member 23 is provided on a concentric circle having the same diameter as that provided in the pad portion 2. Using this mechanism, the top plate 21 and the pad portion 2 are connected by the connecting member 23 with the center of the top plate 21 and the pad portion 2 aligned in the Z-axis direction. A gap is secured between the top plate 21 and the pad portion 2. In the present embodiment, the dimension of the gap (dimension d1 in FIG. 2B) is set to 5 mm to 10 mm.

  The side plate 22 is a tubular body whose outer diameter is substantially the same as the outer diameter of the top plate 21 and whose inner diameter is larger than the diameter of the pad portion 2, and the positions of the outer peripheral portion of the top plate 21 and the outer peripheral portion of the side plate 22 are the same. Thus, the side plate 22 is joined to the top plate 21 by welding or the like in a state where the lower surface of the top plate 21 and the upper end portion of the side plate 22 are in contact with each other. In addition, this junction part has airtightness.

  The top plate 21 to which the side plate 22 is bonded in this way is connected to the pad portion 2 via the connecting member 23, so that the pad portion 2 has a gap 24 between the upper surface and the side surface of the pad portion 2. The upper surface and the side surface of the pad portion 2 are covered so as to cover from above. An opening 28 is formed between the side plate 22 and the pad portion 2 at the lower end portion 27 of the side plate 22. In the present embodiment, the opening portion 28 is formed over the entire circumference of the pad portion 2, and the size of the gap between the side plate 22 and the pad portion 2 and the width of the opening portion 28 (dimension d2 in FIG. 2B) are as follows. It is set to 2 mm to 3 mm.

  Further, the height of the side plate 22 is such that the lower end 27 of the side plate 22 is the bottom surface of the pad portion 2 by a predetermined dimension when the top plate 21 to which the side plate 22 is joined is connected to the pad portion 2 via the connecting member 23. 11 is set to be higher than 11. In the present embodiment, the difference in height between the lower end portion 27 and the bottom surface 11 (dimension d3 in FIG. 2B) is set to 2 mm to 3 mm, and is set to be approximately the same as the dimension d2.

  The pipe connection port 25 is a tubular body whose inner diameter is substantially the same as the diameter of the hole of the top plate 21, and the end of the pipe 26 whose other end is connected to the suction means 4 is connected to the pipe connection port 25.

  The pipe connection port 25 is in a state where the upper surface of the top plate 21 and the lower end portion of the pipe connection port 25 are abutted so that the positions of the inner periphery of the top plate 21 and the inner periphery of the pipe connection port 25 coincide. The top plate 21 is joined by welding or the like. In addition, this junction part has airtightness.

  The suction means 4 is a means for generating a suction force, such as a factory vacuum or a commercially available vacuum cleaner.

  The suction means 4 is connected to the pipe 26, and the suction means 4 is connected to the cover portion 3 through the pipe 26, whereby the gas present in the gap 24 is sucked by the operation of the suction means 4.

  The pipe 26 is a resin hose or the like and has flexibility. Therefore, the movement of the pad portion 2 and the cover portion 3 is not hindered by the pipe 26, and the entire surface of the cleaning object can be cleaned.

  Next, FIG. 3 shows a suction form of foreign matter by the cleaning device in the present embodiment.

  As described above, the object to be cleaned by the cleaning device 1 of the present invention is mainly the vibration plate 92 included in the levitation conveyance heat treatment device, and the cleaning by the cleaning device 1 causes the pad portion 2 to float by the ultrasonic vibration of the vibration plate 92. It is carried out while moving on the diaphragm 92 by a moving means (not shown) under the state.

  When the suction means 4 is operated in a state where the pad portion 2 is lifted in this way and suction force is generated in the gap 24 through the pipe 26 and the pipe connection port 25, in the opening 28 and the through hole 12 leading to the gap 24. An air flow from the bottom to the top is generated. As a result, the foreign matter 95 is sucked through the opening 28 and the through hole 12 and cleaned.

  Here, since the diaphragm 92 is required to efficiently transmit the vibration from the ultrasonic generator to an object (such as the cleaning apparatus 1 or the substrate W) that floats, it is usually formed of aluminum having a good vibration transmission rate. Has been. For this reason, the vibration plate 92 is relatively soft, and if the foreign matter 95 such as a small glass piece is dragged, the vibration plate 92 may be easily scratched. Since the surface of the diaphragm 92 is cleaned in a state where the ultrasonic vibration is levitated by vibration, that is, cleaning is performed in a non-contact state, the cleaning apparatus 1 itself does not damage the diaphragm 92, and the cleaning apparatus 1 Is less likely to drag the foreign matter 95.

  Next, the size of foreign matter that can be cleaned by the cleaning device 1 will be described.

  First, the foreign matter 95 sucked through the through-hole 12 is sucked after passing through the space between the bottom surface 11 of the floating pad portion 2 and the diaphragm 92, and therefore the foreign matter 95 that can be sucked through the through-hole 12. The size is limited to a diameter smaller than the flying height of the pad portion 2 (distance between the diaphragm 92 and the bottom surface 11; in this embodiment, 50 μm to 100 μm). Accordingly, a relatively large foreign object cannot be sucked from the through hole 12.

  On the other hand, since the height of the lower end portion 27 of the cover portion 3 is higher than the bottom surface 11 of the pad portion 2 as described above, a foreign matter having a diameter larger than the flying height of the pad portion 2, for example, shown in FIG. Even the foreign matter 96 can pass between the lower end portion 27 and the diaphragm 92 and reach directly below the opening portion 28. Such foreign matter 96 is also sucked into the cleaning device 1 through the opening portion 28 and cleaned. Is possible.

  In the present embodiment, as described above, the lower end portion 27 is at a position 2 mm to 3 mm higher than the bottom surface 11, and the width of the gap 24 is equal to or larger than this dimension, so that the cleaning device 1 has a diameter of about 2 mm to 3 mm. The foreign matter 96 can also be suction-cleaned. Here, foreign matter having a diameter exceeding 2 mm to 3 mm on the diaphragm 92 can be easily confirmed visually even in a yellow lamp environment in a clean room, and can be removed by hand. It is difficult to visually confirm minute foreign matters and particles of 2 mm to 3 mm or less. On the other hand, the cleaning device 1 of the present invention can suck all foreign matter 95 and foreign matter 96 that are difficult to visually confirm, and can easily clean the entire surface of the diaphragm 92.

  In the present embodiment, the through-hole 12 is provided in the pad portion 2, but this through-hole 12 not only sucks the foreign matter 95, but also suppresses the rattling of the cleaning device 1 and prevents the movement of the cleaning device 1. It has the effect of facilitating control.

  When the cleaning device 1 is in the state of ultrasonic vibration levitation on the diaphragm 92, there is almost no resistance to movement in a direction parallel to the plane of the diaphragm 92 (direction parallel to the XY plane in FIG. 3). The cleaning device 1 may move greatly due to a slight external force, and it may be difficult to control the movement of the cleaning device 1. On the other hand, the through-hole 12 is provided in the pad portion 2, and the outside air in the vicinity of the bottom surface 11 is sucked through the through-hole 12, whereby an adsorption force is generated between the diaphragm 92 and the bottom surface 11, and the cleaning device The effect of pressing 1 against the diaphragm 92 is produced. It is possible to give an appropriate resistance against movement in a direction parallel to the surface of the diaphragm 92 by a balance between the attraction force and the levitation force (radiated sound pressure) due to ultrasonic vibration. Thereby, control of movement of cleaning device 1 becomes easy.

  On the other hand, even if there is no through-hole 12, the effect of pressing down can be obtained by sucking outside air from the opening 28, but the effect can be enhanced by providing the through-hole 12.

  With the above cleaning device, foreign substances can be removed without damaging the object to be cleaned.

DESCRIPTION OF SYMBOLS 1 Cleaning apparatus 2 Pad part 3 Cover part 4 Suction means 11 Bottom surface 12 Through-hole 21 Top plate 22 Side plate 23 Connecting member 24 Gap 25 Pipe connection port 26 Pipe 27 Lower end part 28 Opening part 90 Levitation conveyance heat treatment apparatus 91 Substrate floating apparatus 92 Vibration Plate 93 Ultrasonic wave generator 94 Heating device 95 Foreign material 96 Foreign material W Substrate

Claims (2)

A pad portion that has a flat bottom surface facing the object to be cleaned, and floats on the object to be cleaned by ultrasonic vibration of the object to be cleaned;
A cover portion covering the upper surface and the side surface of the pad portion with a gap between the upper surface of the pad portion and the side surface of the pad portion;
A suction means connected to the cover part, for sucking a gas in a gap between the pad part and the cover part;
With
An opening is formed between the lower end part of the cover part and the side of the pad part, and the lower end part is in a position higher than the bottom face of the pad part.   The pad portion has a through hole penetrating the top surface or side surface and bottom surface of the pad portion, and the suction means also sucks gas near the bottom surface of the pad portion through the through hole. The cleaning apparatus according to claim 1.

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