JP2015225945A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device which reliably cleans a peripheral end side surface of a cleaned body even when a contour of the cleaned body is not a perfect circle.SOLUTION: A cleaning device 1 of the invention includes: a support body 20 which supports a cleaned body 10; a main surface brush 30 which contacts with a main surface 10a of the cleaned body 10 supported on the support body 20 and rotates to clean the main surface 10a; a side surface brush 35 which contacts with a peripheral edge side surface 10b of the cleaned body 10 to clean the side surface 10b; and a biasing mechanism 50 which constantly biases the side surface brush 35 toward a center O of the cleaned body 10.

Description

  The present invention relates to a cleaning apparatus used in a semiconductor manufacturing process or the like, and more specifically, to a brush scrub cleaning apparatus that cleans the main surface and peripheral end side surface of an object to be cleaned such as a silicon wafer using a brush.

  In recent years, with the miniaturization of semiconductor devices, improvement in yield in wet processing such as etching and cleaning has become an important issue. In particular, in a cleaning apparatus, in order to remove contaminants and particles adhering to the surface of, for example, a semiconductor wafer (hereinafter simply referred to as a wafer) as an object to be cleaned, it is horizontally (horizontal) or vertically (longitudinal). By rotating the cylindrical brush on the wafer placed in contact with the cylindrical side surface as the contact surface, the main surface and peripheral side surface of the wafer rotating as the brush rotates are rubbed with the brush in one direction. A brush scrub device that scrapes out is conventionally known (for example, see Patent Document 1).

JP 2000-183020 A

  By the way, in general, an orientation flat (hereinafter referred to as an orientation flat) which is a notch or a flat surface notch may be provided on the wafer so that the direction of the crystal axis is known.

  However, when the orientation flat is provided, in the brush scrubbing device described above, the side brush that cleans by contacting the peripheral end side surface of the rotating wafer can sufficiently contact the wafer at the orientation flat portion. There are cases where the cleaning of the wafer is insufficient or impossible at this part. Particularly in a highly integrated semiconductor device manufacturing process, highly clean ultra-precision cleaning is required, and reliable cleaning of such orientation flat parts is an urgent issue.

  The present invention has been made paying attention to the above-described problems, and an object of the present invention is to provide a cleaning device that can reliably clean the main surface and the peripheral side surface even when the contour of the object to be cleaned is not a perfect circle. And

  In order to achieve the above-mentioned object, the present invention rotates in contact with the main surface of the object to be cleaned supported on the support, and a support that rotatably supports the object to be cleaned. A cleaning apparatus comprising: a main surface brush for scrub cleaning the main surface; and a rotatable side brush for cleaning the side surface in contact with a peripheral end side surface of the object to be cleaned. And an urging mechanism for constantly urging the side brush in contact with the peripheral side surface of the object to be cleaned toward the center of the object to be cleaned.

  According to the configuration described above, the side brush that contacts the peripheral side surface of the object to be cleaned and cleans the side surface is constantly urged toward the center of the object to be cleaned by the urging mechanism. Therefore, even when the object to be cleaned is not a perfect circle, the side brush moves in the radial direction so as to follow the contour of the outer periphery of the object to be cleaned, and is desired on the peripheral end side surface of the object to be cleaned. Always contact with the pressure of. For this reason, according to the above-described configuration, even when the contour of the object to be cleaned is not a perfect circle, the peripheral side surface can be reliably cleaned.

  In the above configuration, the “main surface” is a surface including the front and back having the largest area among the surfaces constituting the object to be cleaned. For example, when the object to be cleaned is a semiconductor wafer, a transistor These are the front and back surfaces of the wafer on which functional layers such as circuits and patterns composed of wires and wiring are deposited.

  ADVANTAGE OF THE INVENTION According to this invention, even when the outline of a to-be-cleaned body is not a perfect circle, the washing | cleaning apparatus which can wash | clean the main surface and peripheral end side surface reliably is obtained.

It is a schematic plan view which shows the principal part structure (an auxiliary roller is included) of the washing | cleaning apparatus which concerns on one Embodiment of this invention. It is a schematic plan view which shows the principal part structure (an auxiliary roller is not included) of the washing | cleaning apparatus which concerns on one Embodiment of this invention. FIG. 2 is a schematic side view of the cleaning apparatus of FIG. 1 in a cleaning standby state in which a main surface brush is not in contact with a main surface of an object to be cleaned supported on a support. It is a schematic side view of the washing | cleaning apparatus of FIG. 1 of the washing | cleaning state by which the main surface brush contacted the main surface of the to-be-cleaned body supported on a support body. It is a schematic block diagram of the urging mechanism which always urges | biases the side brush which contacts the peripheral edge side surface of the to-be-cleaned body supported on a support body toward the center of a to-be-cleaned body. It is a side view which shows the flow of the gas for drying sprayed with respect to a to-be-cleaned body at the time of the drying process using a drying apparatus. It is a top view which shows the flow of the gas for drying sprayed with respect to a to-be-cleaned body at the time of the drying process using a drying apparatus.

Hereinafter, an embodiment of a cleaning apparatus according to the present invention will be described with reference to the drawings.
In the following embodiments, a semiconductor wafer 10 (see FIG. 1) having a non-circular contour having an orientation flat 10c will be described as an example of the object to be cleaned. The wafer 10 may not be used, and the outline may be a perfect circle.

  FIG. 1 is a schematic plan view showing the main configuration of a cleaning apparatus 1 according to an embodiment of the present invention. The cleaning apparatus 1 is, for example, a so-called in-line cleaning processing apparatus, that is, a loader unit in which a wafer 10 as an object to be cleaned is carried and stored, and a brush that performs brush cleaning in a state where the wafer 10 is rotated. A scrub cleaning unit, a drying unit for drying the cleaned wafer 10, and an unloader unit for storing the cleaned and dried wafer for unloading. Various internal transfer robots move the wafer 10 between the units. It may be provided in the cleaning processing apparatus to be carried in or out, or may be provided as a single cleaning apparatus, and its structure arrangement form is arbitrary. In any case, the wafer 10 to be cleaned is loaded into and unloaded from the cleaning apparatus 1 manually or automatically via a transfer robot.

  Further, in the present embodiment, an example in which the wafer 10 is cleaned in a state in which the wafer 10 is disposed in the horizontal direction in the cleaning apparatus 1 will be described. However, the present invention is directed to an arbitrary angle (from the horizontal direction to the vertical direction). The present invention can also be applied to the case of cleaning in a state of being arranged at various angles.

  As schematically shown in FIG. 1, the cleaning apparatus 1 of the present embodiment includes a support 20 that rotatably supports a wafer 10 while regulating the position of the wafer 10, and a main surface of the wafer 10 that is supported on the support 20. A main surface brush 30 that scrubs the main surface 10a by rotating in contact with the surface 10a, and a rotatable side surface (end surface) brush (hereinafter referred to as the surface 10b that contacts the peripheral end side surface 10b of the wafer 10 and cleans the side surface 10b). 35). Although not shown, the cleaning apparatus 1 may include an injection nozzle that sprays a cleaning liquid (for example, an alkaline cleaning liquid) from the periphery of the wafer 10 supported by the support 20, or through the brushes 30 and 35. The cleaning liquid may be supplied to the wafer 10.

  The support 20 is configured as a plurality (six in FIG. 1) of support rollers 20a to 20f arranged in a circular shape in accordance with the size of the wafer 10 to be supported. Main surface). In addition, the number of the support bodies 20 to be installed is arbitrary (for example, preferably an even number such as 4, 8), and the position of the support bodies 20 may be adjusted. In this case, the support 20 (20a to 20f) has an arrangement and configuration that stably supports the wafer 10 so that the wafer 10 is not dropped (the wafer 10 is not detached). Further, the support 20 is preferably arranged so as not to prevent the optimum installation of the brushes 30 and 35, and further, a holding unit (for example, an arm for holding a wafer) (not shown) of the transfer robot, transfer It is preferable to arrange so as not to block the route.

  Further, as shown in FIGS. 3 and 4, each support body 20 (20 a to 20 f) has a height dimension sufficiently larger than the thickness dimension of the wafer 10, and moves the wafer 10 in the radial direction. A supporting column 21 that restricts (position is controlled), and a hook-shaped (flange-shaped) receiving surface 22 that projects in an annular shape radially from the outer peripheral surface of the supporting column 21 and receives the outer peripheral edge of the main surface 10a on the back side of the wafer 10. And have. In this case, the receiving surface 22 is inclined downward from the support column 21 so that the wafer 10 can be in line contact with the wafer 10 and can support it. Thus, if the contact area between the wafer 10 and the support 20 is reduced, contamination of the back surface of the wafer 10 can be prevented, and the rotational resistance of the wafer 10 during cleaning can be reduced.

  In the present embodiment, each support body 20 is configured as a support roller that freely rotates following the rotation of the wafer 10, but may be driven and controlled by a motor. In any case, the contact resistance and wear resistance during rotation of the wafer 10 may be reduced by incorporating a bearing in the support column 21.

  In the present embodiment, the main surface brush 30 constituting the cleaning apparatus 1 is formed as a cylindrical roll brush, and has a predetermined size so that the main surface 10a on the front and back surfaces of the wafer 10 can be cleaned reliably and efficiently. Installed in position. In the present embodiment, the main planar brush (hereinafter also referred to as a roll brush) 30 is a predetermined circumferential position of the wafer 10 supported on the support 20, and the center of the wafer 10 from the peripheral edge of the wafer 10. It extends in the radial direction of the wafer 10 over a length exceeding O (longer than the radius of the wafer 10). In this case, in this embodiment, a total of two roll brushes 30 are provided on the front and back of the wafer 10 (see FIGS. 3 and 4), but the number of roll brushes 30 to be installed is arbitrary.

  The roll brush 30 is rotated by receiving a driving force of a driving motor (not shown), and applies a rotating force to the wafer 10 by contacting the main surface 10 a of the wafer 10. Further, the roll brush 30 can be moved to and away from the main surface 10a of the wafer 10 by using, for example, an air cylinder.

  Furthermore, the contact area of the roll brush 30 with respect to the wafer 10 can be freely set by adjusting the contact pressure, contact position, etc. of the roll brush 30 up and down (front and back) simultaneously or separately using an air cylinder or the like based on a signal from the sensor. It is. In this case, it is preferable to prevent the rotation axis of the roll brush 30 from tilting in order to prevent the wafer 10 from rotating and cleaning unevenly.

  In addition to the cylindrical roll brush as in the present embodiment, the main planar brush may be configured as, for example, a disc-shaped brush (disc-type brush; disc brush). Such a disk brush is disposed so that the cleaning surface is parallel to the surface of the wafer, and is driven to rotate about a rotation axis perpendicular to the wafer to clean the surface of the wafer. Such a disk brush preferably has a configuration in which the diameter is larger than the radius of the wafer, so that the wafer surface can be uniformly and uniformly cleaned. In addition, the disc brush may be configured, for example, by adding a ring-shaped weight to the rotating shaft portion and applying a load toward the wafer (pressing the disc brush against the wafer surface). Thus, it becomes possible to uniformly and evenly clean the wafer by adjusting the pressing force on the wafer.

  Further, the side brush 35 constituting the cleaning apparatus 1 is formed as a disc-shaped brush (disk brush) having a height dimension larger than the thickness dimension of the wafer 10. The side brush 35 is in contact with the peripheral end side surface 10b of the wafer 10 supported on the support 20 so that the side surface 10b can be cleaned in a predetermined circumferential position of the wafer 10 (in this embodiment, the main plane). Provided at a position substantially opposite to the brush 30 in the radial direction). In the present embodiment, one side brush 35 is provided to face the peripheral side surface 10b of the wafer 10, but the number of side brushes 35 to be installed is arbitrary.

  The side brush 35 is rotated by receiving the driving force of the driving motor 60 shown in FIG. 5 (not shown in FIG. 1), and rotates in contact with the peripheral side surface 10b of the wafer 10. Thus, the rotation speed of the wafer 10 by the roll brush 30 can be adjusted. In particular, in this embodiment, the side brush 35 is rotated so as to brake the rotation of the wafer 10, that is, by rotating slower than the rotation speed of the wafer 10 by the roll brush 30, the speed difference thereof. The peripheral end side surface 10b of the wafer 10 is cleaned by the friction caused by the above.

  The side brush 35 may be moved in the radial direction so as to be detachable from the peripheral end side surface 10b of the wafer 10 by using, for example, an air cylinder. Further, the side brush 35 abuts against the peripheral end side surface 10b of the wafer 10 with a predetermined contact pressure so as to press the wafer 10 against the support body 20, thereby causing vibration (vibration outward in the radial direction) when the wafer 10 rotates. You may make it suppress. Further, in the present embodiment, the side brush 35 is rotated by a motor drive, but may be configured to freely rotate following the rotation of the wafer 10. Further, the rotation directions of the roll brush 30 and the side brush 35 are not limited.

  Further, the cleaning device 1 of the present embodiment further includes a predetermined number of auxiliary rollers 40. In the present embodiment, a total of four auxiliary rollers 40 are provided on the front and back sides of the wafer 10, but the number of auxiliary rollers 40 to be installed is arbitrary, and is arranged only on the front side or the back side of the wafer 10. It may be provided.

  These auxiliary rollers 40 are formed as cylindrical roll brushes, and are positioned at the circumferential position of the wafer 10 between the roll brush 30 and the side brush 35 (preferably in the vicinity of the side brush 35). 10 extends from the peripheral edge of the wafer 10 in the radial direction of the wafer 10 over a length shorter than the length of the roll brush 30. Such an auxiliary roller 40 rotates in contact with the main surface 10a of the wafer 10 to prevent the wafer 10 from wavy during rotational cleaning of the wafer 10 (particularly with respect to the bending of the wafer 10 (relative to the radial direction). It achieves the function of preventing deflection that stabilizes (the deflection in the vertical direction) is 200 μm or less.

  The auxiliary roller 40 is rotated by receiving a driving force of a driving motor (not shown), and moves detachably with respect to the main surface 10a of the wafer 10 using, for example, an air cylinder. You may do it. Moreover, although the auxiliary roller 40 may rotate in the same direction as the rotation direction of the roll brush 30, it may rotate in the reverse direction. By rotating in the reverse direction, the dirt stuck to the main surface 10a of the wafer 10 can be easily removed. Alternatively, as illustrated in FIG. 2, the cleaning device 1 </ b> A may have a configuration in which the auxiliary roller 40 is not provided.

  In addition, the cleaning apparatus 1 of the present embodiment includes a biasing mechanism that constantly biases the side brush 35 that contacts the peripheral end side surface 10 b of the wafer 10 supported on the support 20 toward the center O of the wafer 10. . In particular, in this embodiment, this urging mechanism uses the gravity acting on the weight coupled to the side brush 35 as the urging force. Specifically, as shown in FIG. 5, the urging mechanism includes a thin bendable linear member 50 such as a wire (net thread) whose one end is directly or indirectly coupled to the side brush 35. The guide member 50 is guided in a pulling direction (a direction indicated by an arrow in FIG. 5; see also a broken line arrow in FIG. 1) for moving the side brush 35 coupled to the guide member 50 toward the center O of the wafer 10. And a weight 55 coupled to the other end of the linear member 50 and suspended in the vertical direction.

  The guide means includes, for example, a rail that guides the linear member 50 in a predetermined direction, a pulley 58 around which the linear member 50 is stretched, and the like, which are supported by a housing 70 that supports the motor 60 and other support portions. Is provided.

  According to the urging mechanism with such a simple configuration, the structure of the portion to be cleaned can be simplified, and the position where the urging force is obtained by the pulley that changes the direction of the force or the fulcrum with the slip is set to an arbitrary position. can do. Further, by using the gravity of the weight 55 as the urging force, a stable urging force can be obtained with high accuracy. Thus, in the present invention, the portion that holds the side brush 35 (which is the motor 60 in this embodiment) has a structure that urges the side brush 35 to the end surface of the wafer by the action of gravity. Just do it. In other words, it suffices if the rotation center axis of the side brush 35 is pulled by the action of gravity toward the end surface of the wafer. For this reason, the motor 60 may be installed below the side brush 35. In addition, for example, the motor 60 is held by the housing 70 and rotated by a side brush via a power transmission member such as a gear train. It may be connected to the central axis.

  Further, the pulley 58 may be configured as a rotating guide roller or may be configured as a guide member having a non-rotating curved surface. Further, the linear body 50 is preferably configured not to expand and contract in the direction in which the weight acts (axial direction), and thereby the side brush 35 is displaced (varied) by the load of the weight 55. It is possible to perform stable and uniform cleaning.

  Further, the weight 55 may be detachable from the filament 50, and the weight 55 may be increased or decreased. In this embodiment, the urging mechanism uses the gravity acting on the weight 55 as the urging force. However, the urging mechanism uses a spring force such as a coil spring or a tensile elastic force of a material such as a rubber material as the urging force. Also good.

  Further, the cleaning device 1 of the present embodiment is configured to maintain a certain relationship in the rotation speeds and contact pressures of the brushes 30 and 35 and the auxiliary roller 40. For example, the rotational speed V1 of the roll brush 30 is higher than the rotational speed V2 of the side brush 35, and the rotational speed V2 of the side brush 35 is set to be equal to or higher than the rotational speed V3 of the auxiliary roller 40 (V1> V2 ≧ V3). Is preferred. Specifically, the rotation speed V1 of the roll brush 30 is set to 100 to 300 rpm (for example, 200 rpm), the rotation speed V2 of the side brush 35 is set to 10 to 50 rpm (for example, 20 rpm), and the rotation speed V3 of the auxiliary roller 40 is set. Is set to 6-8 rpm.

  Regarding the contact pressure, the contact pressure P1 of the roll brush 30 with respect to the wafer 10 is larger than the contact pressure P2 of the side brush 35 with respect to the wafer 10, and the contact pressure P2 of the side brush 35 with respect to the wafer 10 is greater than that of the auxiliary roller 40 with respect to the wafer 10. It is preferable that the pressure is set larger than the contact pressure P3.

  By setting the relationship between the rotation speed and the contact pressure as described above, it is possible to suppress or prevent radial deflection during rotation of the wafer 10 while enhancing the cleaning effect on the wafer 10. That is, a good cleaning effect can be obtained even if the wafer 10 is swung about 5.0 mm radially outward during rotation, and even a thin wafer (object to be cleaned) is stable. In this state, it is possible to perform cleaning with certainty.

Next, an operation of cleaning the wafer 10 by the cleaning apparatus 1 having the above configuration will be briefly described.
First, a wafer 10 to be cleaned is carried into the cleaning apparatus 1 manually by an operator or automatically by a transfer robot. At this time, the brushes 30 and 35 and the auxiliary roller 40 are moved by a moving mechanism such as the air cylinder described above so that the wafer 10 can be carried into the circular support region surrounded by the support 20 (20a to 20f) without any obstacles. It is evacuated to a predetermined standby position.

  When the wafer 10 is loaded into the circular support region surrounded by the support 20 (20a to 20f) and the wafer 10 is supported on the support 20, the brushes 30 and 35 and the auxiliary roller 40 are subsequently set in a predetermined manner. Moved to the cleaning position. At this time, the brushes 30 and 35 and the auxiliary roller 40 are in contact with the main surface 10a and the peripheral end side surface 10b of the wafer 10 with the above-described predetermined contact pressure relationship, and preferably the roll brush 30 that holds the wafer 10 from above and below. Thus, the wafer 10 is slightly lifted from the receiving surface 22 of the support 20. By doing in this way, the frictional resistance by the support body 20 at the time of rotation of the wafer 10 can be eliminated.

  In this state, the brushes 30 and 35 and the auxiliary roller 40 are now driven to rotate by the motor with the predetermined rotational speed relationship. The rotation directions at this time are indicated by arrows in FIGS. 1, 3 and 4 (the upper and lower roll brushes 30 are rotated in opposite directions to rotate the wafer 10 in a certain direction without resistance). By this rotation, the wafer 10 is rotated and the support 20 is also rotated following the rotation of the wafer 10. In such a rotating state, the cleaning liquid is sprayed from the periphery of the wafer 10 by an unillustrated spray nozzle, and the cleaning liquid is also supplied from the brushes 30 and 35 as necessary, and the main surface 10a of the wafer 10 is supplied by the roll brush 30. Is washed. At the same time, the side end surface 10b of the wafer 10 is cleaned by the side brush 35, and further, for example, the auxiliary roller 40 is rotated in the reverse direction to promote the separation of dirt stuck to the main surface 10a of the wafer 10.

  In this cleaning step, the biasing mechanism described above is provided, so that the side brush 35 that cleans the side surface 10 b in contact with the peripheral side surface 10 b of the wafer 10 is always applied toward the center O of the wafer 10. Therefore, even when the side brush 35 faces the orientation flat 10c of the wafer 10, the side brush 35 moves inward in the radial direction so as to follow the contour of the outer periphery of the wafer 10 and can contact the orientation flat 10c with a desired pressure. As a result, the peripheral end side surface 10b of the wafer 10 including the orientation flat 10c is reliably cleaned over the entire periphery.

  As described above, when the cleaning in the cleaning apparatus 1 is completed, the process proceeds to the drying process. Specifically, in this drying process, the wafer 10 is manually or automatically carried into the drying apparatus 90 shown in FIGS. As shown in FIGS. 6 and 7, the drying device 90 has a configuration in which a turntable 92 is rotatably arranged in a housing 91, and is arranged on the turntable 92 in a circular configuration. The wafer 10 is supported by a plurality of supports 93 provided. Further, the drying device 90 includes upper and lower spray nozzles 94 for spraying dry gas onto the wafer 10 rotated by the turntable 92. In this case, the lower surface (for the back surface) injection nozzle may be configured to be installed in the rotating shaft.

  Here, the drying device 90 is characterized by a gas spraying configuration that eliminates the need for a conventional chuck for fixing the wafer 10 to the support 93. In the conventional chuck, for example, when the turntable 92 is rotated, the rotating centrifugal force is tilted like a pendulum to chuck the peripheral edge of the wafer 10, but the cleaning liquid remaining on the wafer 10 during the cleaning is turned. The centrifugal force generated by the rotation of the table 92 moves in the outer peripheral direction of the wafer 10 and accumulates in the chuck portion. The accumulated cleaning liquid containing the foreign matters at the time of cleaning is easily dried and solidified by the dry gas while adsorbing foreign matters in the air. Such a dried and solidified product is not preferable because it causes a wafer defect (decrease in yield).

  Therefore, in this drying apparatus 90, when spraying a dry gas from the spray nozzle 94 to the main surface 10a of the wafer 10 with the main surface 10a of the wafer 10 supported at the periphery by the support 93 being totally open, The amount of spraying from above to below is increased with respect to the amount of spraying in the other direction, and the dry gas is sucked downward through a suction port (not shown), so that the wafer 10 is simultaneously pulled by the suction force on the turntable 92 side ( The support 93 is pressed against and held (to prevent the wafer 10 from being lifted). This eliminates the need for a conventional chuck that causes the aforementioned problems.

  In FIGS. 6 and 7, the flow of the dry gas from the injection nozzle 94 is indicated by arrows. In this way, most of the dry gas flows so as to press the outer peripheral edge of the wafer 10 against the support 93, and is sucked downward so as to pass through the gap between the supports 93.

  In addition, it is preferable to form a slit (not shown) penetrating vertically in the support column 93a of the support 93. Such slits allow the cleaning liquid to escape during drying and prevent the cleaning liquid from remaining on the support 93 and prevent dirt and foreign matter from remaining in the vicinity of the support 93 together with the cleaning liquid.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various deformation | transformation implementation is possible in the range which does not deviate from the summary. For example, the urging mechanism described above may apply the urging force to the side brush 35 at an arbitrary position of the side brush 35, but the urging force is at least in a contact position where the side brush 35 contacts the peripheral end side surface 10 b of the wafer 10. To the side brush 35.

1 Cleaning device 10 Wafer (object to be cleaned)
10a main surface 10b peripheral end side surface 20 support 30 main surface brush (roll brush)
35 Side (end face) brush (side brush)
40 Auxiliary roller 50 Striated body (biasing mechanism)
55 weight (biasing mechanism)
58 pulley (biasing mechanism)

Claims (6)

A support that rotatably supports the position of the object to be cleaned, and a main surface brush that scrubs and cleans the main surface by rotating in contact with the main surface of the object to be cleaned supported on the support And a cleaning device comprising a rotatable side brush that contacts the peripheral side surface of the object to be cleaned and cleans the side surface,
A cleaning apparatus comprising: an urging mechanism that constantly urges the side brush, which is in contact with a peripheral side surface of the object to be cleaned, supported on the support, toward the center of the object to be cleaned.   The cleaning apparatus according to claim 1, wherein the biasing mechanism uses gravity acting on a weight coupled to the side brush as a biasing force.   The cleaning apparatus according to claim 1, wherein an auxiliary roller that rotates in contact with the main surface of the object to be cleaned is further provided between the main surface brush and the side brush.   The main surface brush extends from the peripheral edge of the object to be cleaned in a radial direction of the object to be cleaned over a length exceeding the center of the object to be cleaned, and the auxiliary roller extends from the peripheral edge of the object to be cleaned. The cleaning apparatus according to claim 3, wherein the cleaning object extends in a radial direction of the object to be cleaned over a length shorter than a length of the main surface brush.   The cleaning speed according to claim 3 or 4, wherein a rotation speed of the main surface brush is higher than a rotation speed of the side brush, and a rotation speed of the side brush is equal to or higher than a rotation speed of the auxiliary roller. apparatus.  The contact pressure of the main surface brush with respect to the object to be cleaned is larger than the contact pressure of the side brush with respect to the object to be cleaned, and the contact pressure of the side brush with respect to the object to be cleaned is in contact with the auxiliary roller with respect to the object to be cleaned. The cleaning apparatus according to claim 3, wherein the cleaning apparatus is larger than the pressure.

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