JP2017073457A - Washing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently wash a holding surface to be washed and shorten a time required for washing, while downsizing a washing apparatus.SOLUTION: A washing apparatus 1 for washing a holding surface 60a for sucking and holding an object to be processed, the holding surface 60a being included in holding means 6, comprises: washing water supply means 2 for supplying washing water; and washing means 3 for washing the holding surface 60a by brought into contact with the holding surface 60a. The washing means 3 comprises: a rotation shaft 32 arranged in a direction orthogonal to the holding surface 60a; a stone 34 that radially extends taking the rotation shaft 32 as the extension center; two or more brushes 35 that interpose the stone 34 between the brushes and radially extend taking the rotation shaft 32 as the extension center; and a motor 33 that rotates the stone 34 and the brushes 35 around the rotation shaft 32.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a cleaning device for cleaning a holding surface of a holding unit that sucks and holds a workpiece.

  A processing device (grinding device or cutting device) for processing a wafer used in semiconductor manufacturing includes, for example, a holding table for holding the wafer during processing, a transport pad for transporting the wafer on the device, and the like. These holding tables and transport pads can suck and hold the wafer by a holding surface, and this holding surface is composed of a porous member (porous member).

  For example, in a grinding apparatus, after a ground wafer is separated from a holding surface of a holding table, the holding surface is cleaned by a cleaning device so that grinding waste does not enter between the wafer and the holding surface.

  As a cleaning mechanism for cleaning the holding surface, there are brush cleaning, stone cleaning, and two-fluid cleaning, and there is a cleaning device including a cleaning mechanism that combines these (for example, see Patent Document 1). This combination includes a combination of brush cleaning and stone cleaning, and a combination of two-fluid cleaning and stone cleaning. Brush cleaning and two-fluid cleaning play a role of scraping and discharging grinding scraps that have entered the inside of the porous member constituting the holding surface from the inside of the porous member. The stone cleaning plays a role of scraping and removing the grinding dust adhering to the holding surface, and is essential for keeping the holding surface flat.

  Similarly, the cleaning mechanism for cleaning the transfer pad includes a mechanism that combines brush cleaning and stone cleaning, or a mechanism that combines two-fluid cleaning and stone cleaning.

Japanese Patent No. 4672924

  However, for example, the cleaning device described in Patent Document 1 needs to rotate the brush and reciprocate the stone in a horizontal plane, so that there is a problem that the entire cleaning device is enlarged and the installation place is limited. . In addition, it is said that a lot of time can be taken for the cleaning when the waste of the porous material from the inside of the porous member by brush cleaning and the removal of the grinding dust attached to the holding surface by the stone cleaning are sufficiently performed. There is also a problem. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to perform sufficient and efficient cleaning without increasing the size of a cleaning device when cleaning a holding surface of a holding means for sucking and holding a workpiece.

  The present invention for solving the above-mentioned problems is a cleaning device for cleaning a holding surface of a holding means having a holding surface for sucking and holding a workpiece, the cleaning water supplying means for supplying cleaning water, and the holding Cleaning means for cleaning the holding surface in contact with the surface, the cleaning means extending radially about the rotation axis and a rotation axis arranged in a direction perpendicular to the holding surface A cleaning apparatus comprising: a stone; two or more brushes extending radially around the rotation axis with the stone interposed therebetween; and a motor that rotates the stone and the brush about the rotation axis .

  Preferably, the brush cleaning section is disposed closer to the holding surface than the stone cleaning section.

  The cleaning apparatus according to the present invention includes a cleaning water supply unit that supplies cleaning water, and a cleaning unit that contacts the holding surface of the holding unit to clean the holding surface, and the cleaning unit is orthogonal to the holding surface. A rotating shaft arranged in a direction, a stone extending radially around the rotating shaft, two or more brushes extending radially around the rotating shaft across the stone, and a stone centered on the rotating shaft By providing a motor for rotating the brush, only one operation of rotating the rotating shaft is performed, and grinding scraps and the like from the porous member constituting the holding surface are discharged and attached to the holding surface. It is possible to sufficiently remove and remove grinding scraps in a short time. In addition, the size of the cleaning device can be reduced.

  Also, since the brush cleaning part is disposed closer to the holding surface of the holding means than the stone cleaning part, the holding surface is ground and excessively worn by the stone being pressed excessively against the holding surface. It is possible to sufficiently scrape grinding scraps and the like from the inside of the porous member with the brush while preventing this.

FIG. 1A is a perspective view illustrating an example of a cleaning device. FIG. 1B is a perspective view showing a state in which the stone is removed from the cleaning device. It is a perspective view which shows the state which removed one brush and stone from the washing | cleaning apparatus. It is a perspective view which shows an example of the washing | cleaning apparatus provided with the washing water nozzle. It is a side view which shows the state which is aligning with the washing | cleaning apparatus and the holding means which is a washing | cleaning object. It is a side view which shows the state which wash | cleans the holding surface of a holding means with the washing | cleaning apparatus. It is a side view which shows the state which has performed position alignment with the washing | cleaning apparatus of another embodiment, and a holding means. It is a side view which shows the state which wash | cleans the holding surface of a holding means with the washing | cleaning apparatus of another embodiment.

  A cleaning apparatus 1 shown in FIGS. 1A and 1B is an apparatus for cleaning a holding means (holding table or transport pad) to be cleaned, and includes a cleaning water supply means 2 for supplying cleaning water and a holding means. Cleaning means 3 for cleaning the holding surface in contact with the holding surface of the means. The cleaning apparatus 1 can be used by being incorporated in a grinding apparatus or the like, or can be used alone. Moreover, the washing | cleaning apparatus 1 may be comprised so that the washing | cleaning apparatus 1 can be moved with respect to the washing | cleaning object by providing a moving means.

  The cleaning means 3 includes, for example, a disk-shaped support plate 30, a rotary shaft 32 disposed on the bottom surface side of the support plate 30 via a rotary joint 31, a motor 33 that rotationally drives the rotary shaft 32, and a support plate A stone 34 disposed on the rotation shaft 32 and extending radially about the rotation shaft 32; and two brushes 35 disposed on the support plate 30 and extending radially about the rotation shaft 32 across the stone 34; It has.

  The axial direction of the rotary shaft 32 is a direction (Z-axis direction) orthogonal to the X-axis Y-axis plane, and one end of the rotary shaft 32 passes through the inner peripheral side of the rotary joint 31 and is the center on the bottom surface side of the support plate 30. And the other end is connected to the motor 33. The rotary joint 31 is provided so as to allow rotation of the rotary shaft 32 while supporting the rotary shaft 32 when a rotational driving force about the axis (around the Z axis) is applied to the rotary shaft 32. As the motor 33 rotates the rotating shaft 32, the support plate 30 also rotates.

  The brush 35 is, for example, a chemical fiber, a vegetable fiber, or a metal wire made of a resin having elasticity, which is formed in a straight hair shape and densely packed, and a flat brush with its hair ends facing in the + Z direction. It is planted on the surface 350 a of the plate 350 for use. The brush 35 may have a tapered shape in which the diameter is gradually reduced toward the hair tip and the tip is sharpened.

  The brush plate 350 in which the brushes 35 are implanted is, for example, spaced apart from the outer peripheral portion of the support plate 30 by a certain distance in the circumferential direction (in this embodiment, spaced apart from each other by 180 degrees). One is arranged. One end of each of the two brush plates 350 is fixed on the outer peripheral portion of the support plate 30, and the other end extends a predetermined length outward in the radial direction of the support plate 30. That is, the two brushes 35 extend radially about the rotation shaft 32. The brush 35 rotates in a horizontal plane as the rotating shaft 32 rotates.

  The shape of the brush 35 is not limited to the illustrated example, and two or more brushes 35 are disposed on the support plate 30 (for example, four are disposed on the support plate 30 so as to be 90 degrees apart from each other). This is preferable because the cleaning power of the cleaning device 1 is further increased.

  The stone 34 is formed, for example, from a resin bond grindstone, a resin material, or a ceramic material in a rectangular parallelepiped shape. The stone 34 is bonded to the surface 340a of the stone plate 340 formed in a flat plate size corresponding to the stone 34 with an appropriate adhesive or the like. A stone plate 340 to which the stone 34 is bonded is fixed on the support plate 30. The stone 34 is formed so as to have a width that fits between the two brush plates 350 and has a length that is approximately the same as the distance between the outer ends of the two brush plates 350. . For example, the stone 34 is disposed on the support plate 30 so that the center of the stone 34 and the center of the support plate 30 coincide with each other, and one end of the stone 34 is centered on the rotation shaft 32 in the + Y direction. The other end extends a predetermined length in the −Y direction. The stone 34 rotates in a horizontal plane as the rotating shaft 32 rotates.

  Note that the shape and arrangement of the stone 34 are not limited to the examples shown in FIGS. For example, by arranging two stones 34 that are formed to have the same length as the length of the brush 35, spaced apart from each other by 180 degrees in the circumferential direction on the outer peripheral portion of the support plate 30, the rotating shaft 32 is arranged. It is good also as a structure which the stone 34 extends radially as a center. Further, it is preferable that two or more stones 34 are disposed on the support plate 30 because the cleaning power of the cleaning device 1 is further increased.

  In the present embodiment, the brush 35 is implanted on the brush plate 350, and the stone 34 is bonded on the stone plate 340. That is, each is arranged on a separate plate, but the brush plate 350 and the stone plate 340 are integrated into one plate (for example, a flat plate with a cross-shaped outer shape). The brush 35 and the stone 34 may be disposed at predetermined positions on one plate.

  A stone 34 extending radially in the Y-axis direction around the rotation axis 32 and two brushes 35 extending radially in the X-axis direction around the rotation axis 32 across the stone 34 are formed on the support plate 30. By being disposed, a plurality of gaps S (four in the illustrated example) on a horizontal plane having a predetermined size are formed between the brush 35 and the stone 34. For example, after the stone 34 and the brush 35 are rotated in a horizontal plane, grinding scraps scraped or scraped off from the holding surface to be cleaned fall from the gap S and are collected and discarded.

  For example, the rotary joint 31 is provided with a water supply pipe 310, and the water supply pipe 310 communicates with the cleaning water supply source 20 provided in the cleaning water supply means 2. A cleaning water supply pipe 300 (not shown in FIG. 1A) is provided between the rotary joint 31 and the support plate 30, and the cleaning water supplied from the cleaning water supply source 20 is supplied to the water supply pipe 310. And flows into the cleaning water supply pipe 300 from the rotary joint 31. The rotary joint 31 is provided so that the rotating shaft 32 can rotate while allowing the cleaning water to flow into the cleaning water supply pipe 300. The cleaning water supply source 20 may be configured as a two-fluid supply source that can supply high-pressure air together with the cleaning water.

  For example, one end of the cleaning water supply pipe 300 is connected to the brush plate 350. A flow path (not shown) communicating with the cleaning water supply pipe 300 is provided inside the brush plate 350, and the cleaning water injection port 350 b shown in FIG. 2 communicating with the flow path is an upper surface of the brush plate 350. Are aligned and opened in the longitudinal direction. The cleaning water that has flowed into the cleaning water supply pipe 300 passes through the brush plate 350, is sprayed from the cleaning water injection port 350 b, and reaches the object to be cleaned through the gap of the brush 35.

  The cleaning water supplied from the cleaning water supply means 2 is supplied from the outside of the brush 35, for example, in addition to the cleaning water supplied from the inside of the brush 35 as in the present embodiment. May be. That is, for example, as shown in FIG. 3, a washing water nozzle 37 formed in a hollow pipe shape is disposed on the support plate 30 along the side surface of each brush 35. In the illustrated example, the cleaning water nozzles 37 are disposed only on one side of each brush 35, but the cleaning water nozzles 37 may be disposed on both sides of each brush 35, respectively. The cleaning water nozzle 37 communicates with the cleaning water supply pipe 300, and a plurality of cleaning water injection ports 370 are arranged on the side surface of the cleaning water nozzle 37 so as to be aligned in the longitudinal direction. The cleaning water supplied from the cleaning water supply source 20 passes through the cleaning water nozzle 37 and is jetted from the cleaning water injection port 370 to reach the cleaning target.

  As shown in FIG. 4, the holding means 6 to be cleaned by the cleaning apparatus 1 is a transport pad that sucks and holds a workpiece such as a semiconductor wafer. The holding means 6 (conveying pad 6) includes a suction portion 60 that is made of a porous member and sucks a workpiece, and a frame body 61 that supports the suction portion 60. A flow path 62 communicating with the suction source 63 is connected to the upper portion of the suction portion 60, and the suction force generated by the suction source 63 is an exposed surface of the suction portion 60 and a frame through the flow path 62. By being transmitted to the holding surface 60a formed flush with the lower surface of the body 61, the transport pad 6 sucks and holds the workpiece on the holding surface 60a. The transport pad 6 is disposed, for example, on the lower surface of the tip of the arm portion 67 connected to the moving unit 66 and can be moved by the moving unit 66. The conveyance pad 6 sucks and holds the ground surface of the wafer after grinding, for example, so that the grinding dust enters the inside of the suction portion 60 or the grinding dust adheres to the holding surface 60a.

  For example, the flow path 62 communicates with the suction source 62 and also with the blow source 65. The blow source 65 includes an air supply source that supplies compressed air and the like, and a cleaning water supply source that supplies cleaning water. The two fluids consisting of high-pressure air and water supplied from the blow source 65 pass through the flow path 62 and are jetted outward from the holding surface 60a of the adsorption unit 60.

  As shown in FIG. 4, in the brush 35, the hair tip portion mainly serves as a cleaning unit 35 a that performs cleaning by contacting the holding surface 60 a of the transport pad 6. Further, the stone 34 mainly serves as a cleaning unit 34 a that performs cleaning by contacting the holding surface 60 a of the transport pad 6 with the surface thereof. For example, in the cleaning device 1, the height position Z1 of the cleaning portion 35a of the brush 35 when the surface of the support plate 30 is set as the reference position is higher than the height position Z2 of the cleaning portion 34a of the stone 34 by a predetermined distance. It is formed to become. Accordingly, the cleaning portion 35a of the brush 35 is disposed closer to the holding surface 60a than the cleaning portion 34a of the stone 34.

  Hereinafter, the operation of the cleaning apparatus 1 when the holding surface 60a of the transport pad 6 is cleaned by the cleaning apparatus 1 will be described with reference to FIGS. 1 (A), 1 (B) to 2 and 4 to 5. .

  First, as shown in FIG. 4, the moving means 66 moves the transport pad 6 onto the cleaning device 1, so that the holding surface 60 a of the transport pad 6 is moved from the cleaning unit 34 a of the stone 34 and the cleaning unit 35 a of the brush 35. It is positioned so as to face each other, and is arranged in a direction (Z-axis direction) in which the rotation shaft 32 is orthogonal to the holding surface 60a. Further, the transport pad 6 is aligned with the cleaning unit 34a of the stone 34 and the cleaning unit 35a of the brush 35 so that the center of the holding surface 60a of the transport pad 6 and the rotation center of the rotary shaft 32 coincide with each other. .

  After the alignment is performed, the stone 34 and the brush 35 are rotated in a horizontal plane as the rotary shaft 32 is rotationally driven by the motor 33. Further, the transport pad 6 is sent in the −Z direction by the moving means 66, and the holding surface 60a of the transport pad 6 is lowered in the −Z direction.

  Further, cleaning water is supplied from the cleaning water supply source 20, and the cleaning water passes through the brush plate 350 and is sprayed from the cleaning water injection port 350 b shown in FIG. 2 to the holding surface 60 a through the gap of the brush 35. The cleaning water is supplied during the cleaning by supplying two fluids consisting of high-pressure air and water from a blow source 65 communicating with the holding surface 60a of the transport pad 6 instead of the cleaning water supply means 2. May be. In this case, the washing water becomes two fluids, passes through the adsorption unit 60, and is ejected from the holding surface 60a. Further, the supply of the cleaning water from the cleaning water supply source 20 and the supply of the two fluids from the blow source 65 may be performed simultaneously.

  As shown in FIG. 4, the cleaning part 35 a of the brush 35 is disposed closer to the holding surface 60 a than the cleaning part 34 a of the stone 34. Therefore, the holding surface 60a first contacts the cleaning unit 35a of the brush 35 as the holding surface 60a of the transport pad 6 descends in the −Z direction. Then, the cleaning unit 35a (the tip of the brush 35) of the rotating brush 35 enters from the holding surface 60a to a fine hole inside the suction unit 60, and scrapes and discharges the grinding dust and the like that has entered the suction unit 60.

  After the cleaning of the holding surface 60 a by the brush 35 is started, the holding surface 60 a of the transport pad 6 further descends in the −Z direction until it contacts the cleaning part 34 a of the stone 34. When the transport pad 6 is lowered to the position Z2 where the holding surface 60a contacts the cleaning part 34a of the stone 34, the transport pad 6 stops being lowered. As shown in FIG. 5, since the brush 35 in this state is pressed against the holding surface 60a of the transport pad 6 and performs cleaning while being bent in accordance with the shape of the holding surface 60a, the brush 35 may damage the holding surface 60a. Absent. In general, the holding surface 60a of the transport pad 6 tends to have more grinding scraps attached to its outer peripheral region (this tendency is provided in the grinding device to hold the workpiece to be ground). The same applies to the holding surface of the table.) Therefore, during the cleaning of the holding surface 60a, the brush 35 does not necessarily need to be in contact with the entire surface of the holding surface 60a by rotating, and is disposed on the support plate 30 with the stone 34 interposed therebetween as shown in FIG. It is only necessary to be configured to contact at least the outer peripheral region of the holding surface 60a during the cleaning.

  The cleaning unit 34a of the stone 34 that contacts the holding surface 60a while rotating removes the grinding dust firmly attached to the holding surface 60a while scraping it. As shown in FIG. 1, since the stone 34 is disposed on the support plate 30 so as to be sandwiched between the two brushes 35, the stone 34 is held by rotating during the cleaning of the holding surface 60a. It can contact the entire surface 60a.

  The grinding scraps scraped to the holding surface 60a by the brush 35 and the grinding scraps scraped from the holding surface 60a by the stone 34 are washed away from the holding surface 60a by the cleaning water supplied from the cleaning water supply source 20, for example. Further, when two fluids consisting of high-pressure air and water are supplied from the blow source 65, the grinding waste is washed away from the inside of the adsorption unit 60 by these two fluids.

  Since the grinding waste removed from the holding surface 60a falls from the gap S shown in FIG. 1 formed between the rotating stone 34 and the brush 35, the cleaning portion 34a of the stone 34 and the brush 35 are removed. There is no accumulation in the cleaning part 35a.

  After the grinding scraps are sufficiently removed from the inside of the suction portion 60 of the transport pad 6 and the holding surface 60a, the transport pad 6 is raised in the + Z direction by the moving unit 66 and separated from the cleaning unit 3, thereby cleaning the cleaning device. The cleaning of the holding surface 60a of the transport pad 6 by 1 is completed.

  In the cleaning apparatus 1, the cleaning unit 3 includes a rotating shaft 32 arranged in a direction orthogonal to the holding surface 60 a, stones 34 that extend radially about the rotating shaft 32, and a rotating shaft across the stone 34. Two brushes 35 extending radially around the center 32, and a motor 33 that rotates the stone 34 and the brush 35 about the rotation shaft 32. Therefore, the stone 34 and the brush 35 can be rotated only by performing one operation of rotating the rotating shaft 32 by the motor 33, and the rotating stone 34 and the brush 35 are applied to the holding surface 60 a of the transport pad 6. By bringing them into contact with each other, it becomes possible to simultaneously discharge the grinding dust and the like from the inside of the suction portion 60 made of a porous member and remove the grinding dust and the like attached to the holding surface. That is, immediately after grinding scraps are scraped from the suction portion 60 to the holding surface 60a by the brush 35, the grinding scraps can be scraped off from the holding surface 60a by the stone 34, and the scraped grinding scraps are washed. Since it can be washed away with water, there is no waste in a series of cleaning operations. Therefore, the discharge of the grinding waste from the inside of the suction part 60 and the removal and removal of the grinding waste adhering to the holding surface 60a are sufficiently performed, and the time required for cleaning is shortened. In addition, the size of the cleaning device 1 can be reduced.

  Further, since the cleaning portion 35a of the brush 35 is disposed closer to the holding surface 60a of the holding means 6 than the cleaning portion 34a of the stone 34, the stone 34 is in contact with the holding surface 60a and is capable of scraping grinding scraps. While the cleaning at the position is performed, the scrap 35 can be sufficiently scraped from the inside of the suction portion 60 by the brush 35, and the holding surface 60a is ground by the stone 34 being excessively pressed against the holding surface 60a. To prevent uneven wear.

  The cleaning device 1 according to the present invention is not limited to the above embodiment, and the size and shape of each component illustrated in the accompanying drawings are not limited to this, and the effect of the present invention is not limited thereto. Can be appropriately changed within a range in which can be exhibited. Further, the holding means 6 to be cleaned is not limited to the transport pad 6, and may be a holding table that is provided in a grinding apparatus and holds a workpiece to be ground. In this case, for example, the cleaning device 3 is configured to be movable with respect to the holding table, and when the cleaning device 3 is lowered, the stone 34 and the brush 35 are located above the holding surface of the holding table. Clean from the side.

  Further, for example, as shown in FIG. 6, a biasing means such as a spring 38 may be interposed between the stone plate 341 and the stone 34. In this configuration, in a state where the spring 38 is extended, the height of the cleaning portion 35a that is the hair tip of the brush 35 planted on the stone plate 351 and the height of the upper surface 34a of the stone 34 may coincide with each other. . In a state where the holding surface 60a of the suction unit 60 is not in contact with the cleaning unit 35a and the upper surface 34a, the spring 38 is extended and the stone 34 is biased upward (toward the holding surface 60a). .

  On the other hand, as shown in FIG. 7, when the transport pad 6 is lowered and the holding surface 60a is pressed against the cleaning portion 34a of the stone 34, the spring 38 contracts and the stone 34 descends. At this time, as the transport pad 6 descends, the tip 35a of the brush 35 can be inserted from the holding surface 60a to the minute hole inside the suction part 60, so that the cleaning effect is enhanced. Further, the force by which the stone 34 presses the holding surface 60a by the spring 38 is alleviated, and the holding surface 60a can be suppressed from being excessively pressed.

1: Cleaning device
2: Washing water supply means 20: Washing water supply source 3: Washing means
30: Support plate 31: Rotary joint 32: Rotating shaft 33: Motor 300: Washing water supply pipe 310: Water supply pipe
34: Stone 34a: Stone cleaning section 340, 341: Stone plate
340a: Stone plate surface 35: Brush 35a: Brush cleaning section 350, 351: Brush plate
350a: surface of the brush plate 350b: cleaning water injection port 37: cleaning water nozzle 370: cleaning water injection port 38: spring 6: holding means (conveying pad) 60: suction part 61: frame body 62: flow path 60a: holding Surface 63: Suction source 66: Moving means 67: Arm part 65: Blow source

Claims (2)

A cleaning device for cleaning the holding surface of a holding means having a holding surface for sucking and holding a workpiece,
Cleaning water supply means for supplying cleaning water, and cleaning means for cleaning the holding surface in contact with the holding surface,
The cleaning means includes
A rotating shaft arranged in a direction perpendicular to the holding surface;
A stone that extends radially about the rotation axis, two or more brushes that extend radially about the rotation axis across the stone, and the stone and the brush about the rotation axis And a motor for rotating.   The cleaning device according to claim 1, wherein the cleaning unit of the brush is disposed closer to the holding surface than the cleaning unit of the stone.

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