JP7635572B2 - Substrate cleaning method and substrate cleaning apparatus - Google Patents

Description

This disclosure relates to a substrate cleaning method and a substrate cleaning apparatus.

In the manufacturing process of semiconductor devices, various processes are performed on the semiconductor wafer (hereafter referred to as wafer) which serves as the substrate. One of these processes is a process in which a brush is slid over the back surface of the wafer to clean it. Patent Document 1 shows an apparatus for performing such a cleaning process.

JP 2008-177541 A

This disclosure provides a technology that can quickly complete a cleaning process that involves sliding a brush relative to the underside of a substrate.

The substrate cleaning method disclosed herein includes a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
The first brush has a higher elasticity than the second brush,
the cleaning step includes a step of sliding the first brush and the second brush against the substrate such that the first brush follows the second brush;
The method includes a step of rotating an array of brushes arranged in the order of the first brush, the second brush, and the first brush in the rotation direction around a rotation axis extending in the vertical direction, or in the order of the second brush, the first brush, and the second brush in the rotation direction, in a clockwise direction and a counterclockwise direction in a plan view,
The washing step comprises:
a first cleaning step of positioning one of the brushes in the array as an unused brush at a lower position than the other brushes during the clockwise revolution of the array, and sliding the second brush and a first brush following the second brush against the substrate by the revolution;
a second cleaning step in which one brush of the array, different from the unused brush in the first cleaning step, is placed as an unused brush at a lower position than the other brushes while the array is rotating in the counterclockwise direction, and the second brush and a first brush following the second brush are slid over the substrate;
Includes.
The substrate cleaning method disclosed herein includes a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
a first sliding step of pressing only the first brush out of the first brush and the second brush against a lower surface of the substrate and sliding the brush;
a second sliding step of pressing only the second brush out of the first brush and the second brush against the lower surface of the substrate and sliding the brush against the lower surface of the substrate;
The cleaning process includes a step of lowering the first brush and raising the first brush after performing the first sliding process and before performing the second sliding process, and pressing the second brush against the substrate while the first brush is kept pressed against the substrate.
The substrate cleaning method disclosed herein includes a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
the second brush includes a first sliding surface having a first height that slides against the substrate, and a second sliding surface that is elastic and is higher than the first height;
a step of raising and lowering the second brush between a first position where the first sliding surface and the second sliding surface are in contact with the substrate and a second position where only the second sliding surface of the first sliding surface and the second sliding surface is in contact with the substrate,
the cleaning step includes a positioning step of positioning the first brush at a position where a sliding surface of the first brush slides against the substrate while the second brush is located at the second position;
The sliding surface of the first brush in the positioning step is lower than the first sliding surface when no pressing force against the substrate is applied, and is higher than the second sliding surface .
The substrate cleaning method disclosed herein includes a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
a covering portion is provided to cover the first brush and the second brush from above,
a step of rotating the first brush and the second brush together about a rotation axis extending in a vertical direction and moving the first brush and the second brush between a waiting area below the covering portion where the first brush and the second brush are kept waiting and a position where the first brush and the second brush are each pressed against the substrate;
Equipped with.

According to the present disclosure, the cleaning process, which is performed by sliding a brush relative to the underside of a substrate, can be completed quickly.

FIG. 2 is a plan view of a cleaning device that performs the process according to the first embodiment of the present disclosure. FIG. 2 is a vertical sectional side view of the cleaning device. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 11 is a side view of a cleaning device that performs a process according to a second embodiment. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 2 is a plan view showing a process in the cleaning device. FIG. 4 is a schematic diagram of a brush of the cleaning device. FIG. 13 is a plan view of a cleaning device that performs a process according to a third embodiment. FIG. 13 is a plan view of a cleaning device that performs a process according to a modified example of the third embodiment. FIG. 13 is a plan view of a cleaning device that performs a process according to a modified example of the third embodiment. FIG. 13 is a plan view of a cleaning device that performs a process according to a fourth embodiment. FIG. 13 is a plan view of a cleaning device that performs a process according to a modified example of the fourth embodiment. FIG. 13 is a side view of a cleaning device that performs a process according to a fifth embodiment. FIG. 4 is a perspective view of a brush provided in the cleaning device.

First Embodiment
A cleaning apparatus 1 for carrying out a first embodiment of the substrate cleaning method of the present disclosure will be described with reference to the plan view of FIG. 1 and the vertical cross-sectional side view of FIG. 2. In the cleaning apparatus 1, which is an embodiment of the substrate cleaning apparatus, cleaning is performed by simultaneously pressing two brushes against the back surface (lower surface) of a wafer W, which is a circular substrate having a resist film formed on its front surface (upper surface), and sliding them relative to each other. Therefore, different positions on the lower surface of the wafer W are processed simultaneously. The wafer W, the back surface of which has been cleaned in this manner, is transferred to an exposure machine, and the resist film is exposed according to a predetermined pattern. If foreign matter is attached to the back surface of the wafer W during this exposure process, the wafer W is placed so as to float from the stage of the exposure machine, causing the distance between the optical system of the exposure machine and the wafer W to deviate from the design value, resulting in defocusing. However, this is prevented by processing the wafer W in the cleaning apparatus 1.

The cleaning device 1 includes a base body 11, a spin chuck 12, a cup 3, and a cleaning processing section 4. The base body 11 is formed in a rectangular shape in a plan view, and a wafer W is transported to the cleaning device 1 from one end of the base body 11 in the longitudinal direction by a transport mechanism (not shown) provided outside the cleaning device 1. This end side will be described as the front side. In the following description, left and right refer to left and right when viewed from the rear to the front. The base body 11 includes a rectangular recess 13 whose longitudinal direction is the front-rear direction, and the inside of this recess 13 is configured as a processing area for the wafer W. The front-rear direction is the direction in which the center of the spin chuck 12 (= the center of the held wafer W) described later and the pivot axis (central axis R1) for pivoting the brush that cleans the wafer W are aligned.

A spin chuck 12 is provided at the front side of the processing area in the recess 13. The spin chuck 12 is a circular stage that holds the wafer W horizontally by adsorbing the center of the lower surface of the wafer W. The lower side of the spin chuck 12 is connected to a rotation mechanism 15 via a shaft 14, and the rotation mechanism 15 rotates the spin chuck 12 in a circumferential direction so that the wafer W held by the spin chuck 12 rotates around a vertical axis, specifically, for example, clockwise in a plan view (top view). Three vertical support pins 16 (only two are shown in FIG. 2 ) are arranged on the sides of the spin chuck 12 at intervals along the rotation direction of the spin chuck 12. The support pins 16 are raised and lowered by a lifting mechanism 17, and the wafer W can be transferred between the transfer mechanism, the spin chuck 12, and a non-rotating chuck 35 described later.

A cylindrical portion extending upward from the bottom of the base body 11 is provided to surround the spin chuck 12, rotation mechanism 15, support pins 16, and lifting mechanism 17, and is configured as an air knife 18. The upper end surface of the air knife 18 forms an inwardly sloping surface. Discharge ports 19 that discharge, for example, air upward are provided at intervals in the circumferential direction on the sloping surface. When the back surface of the wafer W is held by suction on the spin chuck 12, the upper end of the air knife 18 is close to the back surface of the wafer W, and air is discharged from the discharge ports 19 to prevent the cleaning liquid from adhering to the center of the back surface of the wafer W.

A drain port 22 is provided at the bottom of the recess 13 of the base body 11. An upright exhaust pipe 23 for exhausting air from inside the recess 13 is provided at a position closer to the air knife 18 than the drain port 22, and exhaust is performed from the exhaust pipe 23 during processing of the wafer W. A flange 24 is provided that extends outward above the exhaust pipe 23 from the lower part of the air knife 18, and the outer end of the flange 24 is bent downward outside the exhaust pipe 23 to prevent waste liquid from flowing into the exhaust pipe 23.

The cup 3 is configured as a cylinder that surrounds the air knife 18 and has an upper end that protrudes inward. The cup 3 surrounds the side circumference of the wafer W during processing, preventing the scattering of waste liquid. When the wafer W is held by the spin chuck 12 or the non-rotating chuck 35 described below, the wafer W is held so as to be concentric with the cup 3. Support parts 31 extend from the left and right outer walls of the cup 3 toward the outer edge of the recess 13 and are connected to a horizontal movement mechanism 32 provided on the base body 11, and the cup 3 can be moved back and forth within the recess 13 by the horizontal movement mechanism 32. The front side and rear side of the movement area of the cup 3 are referred to as the front position and the rear position, respectively. Figure 1 shows the cup 3 in a state where it is positioned in the front position, and the center of the cup 3 at the front position coincides with the center of the spin chuck 12 in a plan view. The center of the cup 3 at the rear position is located behind the air knife 18.

The horizontal movement mechanism 32 is connected to a lifting mechanism 33, and can be raised and lowered together with the cup 3 relative to the base body 11. This lifting mechanism 33 allows the cup 3 to be raised and lowered between an upper position where the upper surface of the non-rotating chuck 35 (support surface for the wafer W) is higher than the upper surface of the spin chuck 12 (support surface for the wafer W) and a lower position where the upper surface of the non-rotating chuck 35 is lower than the upper surface of the spin chuck 12.

Two bridges 34 are formed inside the cup 3, which sandwich the air knife 18 from the left and right and extend forward and backward, and each bridge 34 is provided with a non-rotating chuck 35. The non-rotating chuck 35 adsorbs the outer area of the center of the back surface of the wafer W, holding the wafer W horizontally. The non-rotating chuck 35 and the spin chuck each form a substrate holder, and the wafer W is held by the non-rotating chuck 35 when processing the center of the back surface of the wafer W, and by the spin chuck 12 when processing the peripheral edge of the back surface of the wafer W, and processed by a brush.

A nozzle 36 is provided near the spin chuck 12 in the area surrounded by the cup 3, and a cleaning liquid such as pure water is ejected diagonally upward and backward. By ejecting the cleaning liquid in such a direction, the cleaning liquid is supplied to the center of the underside of the wafer W when the wafer W is held by the non-rotating chuck 35 in the rear position, and to the peripheral portion of the underside of the wafer W when the wafer W is held by the spin chuck 12 in the front position. A brush 51, described below, slides over the area to which the cleaning liquid is thus supplied.

Next, the cleaning processing section 4 will be described. This cleaning processing section 4 and the above-mentioned spin chuck 12 form a sliding mechanism for cleaning by sliding a brush against the wafer W. The cleaning processing section 4 has a horizontal circular stage 41 provided in the recess 13. The stage 41 has a stage body 42 equipped with a lifting mechanism, and rotation mechanisms 43, 44. Adjacent portions in the circumferential direction on the upper part of the stage 41 are respectively configured as the rotation mechanisms 43, 44, and these rotation mechanisms 43, 44 are each formed in a fan shape in a plan view. The stage body 42 allows the rotation mechanisms 43, 44 to be raised and lowered independently of each other.

The stage 41 is configured to be rotatable around its central axis R1. Therefore, the stage 41 rotates around a longitudinal axis, specifically a vertical axis. This central axis R1 is located behind the air knife 18, near the periphery of the cup 3 at the forward position. The direction in which the central axis R1 and the center of the spin chuck 12 are aligned is aligned with the direction of forward and backward movement of the cup 3.

Note that the positions of the rotating mechanisms 43 and 44 are displaced because the stage 41 rotates as described above, but the right rotating mechanism and the left rotating mechanism when both the rotating mechanisms 43 and 44 are located on the forward side are indicated as 43 and 44, respectively. Above these rotating mechanisms 43 and 44, horizontal circular brushes 51 are provided. These two brushes 51 are configured in the same way, and are made of elastic materials such as sponge or resin, and their upper end surfaces form a sliding surface that is pressed against the lower surface of the wafer W and slides. The lower side of each brush 51 is connected to the rotating mechanisms 43 and 44 via a shaft 52, and each brush 51 is rotated around the central axis of the brush 51 by the rotating mechanisms 43 and 44. The central axis of the brush 51 extends in the vertical direction, more specifically, in the vertical direction. By configuring the cleaning processing unit 4 in this way, each brush 51 moves in a revolving manner around the central axis R1 of the stage 41 as the revolving axis. That is, it can move so as to revolve around the central axis R1 as the revolution axis. Furthermore, the brush 51 is configured to be rotatable by the rotation mechanisms 43 and 44. In this embodiment, the brushes 51A and 51B rotate counterclockwise in a plan view.

In the first embodiment, the two brushes 51 are a first brush and a second brush. To further explain the arrangement of the brushes 51, the two brushes 51 are arranged close to each other in a plan view along the circumferential direction of the stage 41, and are each arranged on the periphery of the stage 41 so that the centers of the brushes 51 are equidistant from the central axis R1. Note that the brushes 51 may be distinguished from each other by calling the brush connected to the rotation mechanism 43 51A and the brush connected to the rotation mechanism 44 51B.

As mentioned above, the cup 3 moves between the front and rear positions, and the waiting section 25 is provided behind the cup 3 in the front position and to the left of the center of the left and right of the cup 3. In order not to interfere with the cup 3 moving in this manner, the waiting section 25 is provided below the bottom end of the cup. The waiting section 25 has two recesses lined up in front and behind, with the lower side open to accommodate the two brushes 51, respectively, and the inside of the recesses is configured as a waiting area 26 for waiting the brushes 51A and 51B. Therefore, the waiting section 25 is configured as a covering section that covers the brush 51 from above, and supplies cleaning liquid to the brushes 51A and 51B waiting in the waiting area 26 to clean them.

As described above, brush 51 is configured to be able to revolve (rotate around central axis R1 of stage 41) and rise and fall. This revolve and rise and fall allows brush 51 to move between a position where it is pressed against the underside of wafer W to perform cleaning, and waiting area 26. Note that for brush 51 and brush 53 described below, when positioned on the underside of wafer W, the height at which they are away from wafer W and do not perform processing may be referred to as a non-processing position, and the height at which they are pressed against wafer W to perform processing may be referred to as a processing position.

The standby section 25 will be further described. The left end L1 of the standby area 26 (i.e., the left end of the brush 51 waiting in the standby section 25) is located closer to the center of the cup 12 than the left end L2 of the cup 3. In other words, the left end of the standby area 26 does not protrude leftward from the left end of the cup 3. Since the standby section 25 is provided to the left of the left-right center of the cup 3, the right end of the standby area 26 does not protrude rightward from the right end of the cup. This layout prevents the cleaning device 1 from becoming larger in width from left to right. Even if the left end L1 of the standby area 26 and the left end L2 of the cup 12 are aligned, the installation of the standby section 25 can prevent the device from becoming larger in width from left to right.

The cleaning apparatus 1 is provided with a control unit 10 configured by a computer, and the control unit 10 is provided with a program. This program is structured to output control signals to each part of the cleaning apparatus 1 to control the operation of each part so that a series of processing operations described below can be performed on the wafer W. Specifically, the rotation of the spin chuck 12 by the rotation mechanism 15, the movement of the cup 3 by the horizontal movement mechanism 32, the elevation of the support pins 16 by the elevation mechanism 17, the operation of each part constituting the cleaning processing unit 4, the ejection of air from the air knife 18, the ejection of cleaning liquid from the nozzle 36, etc. are controlled. Specifically, the operation of each part of the cleaning processing unit 4 is, for example, the rotation, revolution, and elevation of the brush 51. The above program is stored in the control unit 10 in a state where it is stored in a storage medium such as a hard disk, a compact disk, a DVD, or a memory card.

Next, the processing of the wafer W by the cleaning apparatus 1 will be described with reference to the plan view of FIG. 3. In each plan view explaining the processing of the apparatus from FIG. 3 onwards, the spin chuck 12, the non-rotating chuck 35 and the brushes that are in contact with the back surface of the wafer W are shown with solid lines, and those that are away from the back surface of the wafer W are shown with dotted lines or are not shown at all. In order to make it easier to understand the positional relationship of each part, the imaginary line L3 that passes through the center of the spin chuck 12 and extends left and right, the imaginary line L4 that passes through the central axis R1 of the stage 41 and extends left and right, and the imaginary line L5 that passes through the center of the spin chuck 12 and the central axis R1 and extends forward and backward are each shown with a dashed dotted line.

With the cup 3 in the forward and lower positions and the brushes 51 in the waiting area 26, the wafer W having a resist film formed on its surface as described above is transported to the cleaning device 1 by the transport mechanism, and the support pins 16 rise to support the wafer W. Then, after the cup 3 moves to the upper position, the support pins 16 descend and the wafer W is transferred to the non-rotating chuck 35, where it is suction-held. Meanwhile, the brush 51 descends from the waiting area 26, revolves, passes under the lower end of the cup 3, and moves below the wafer W, with the brushes 51A and 51B positioned to the right and left of the imaginary line L5, respectively (FIG. 3(a)).

Then, when the cup 3 moves to the rear position, the nozzle 36 ejects the cleaning liquid and supplies it to the center of the wafer W. Then, the brush 51 rotates (spins) and rises from each non-processing position to the processing position and is pressed against the center of the underside of the wafer W. Furthermore, as the stage 41 rotates, the brush 51 alternately revolves clockwise and counterclockwise, so that the brush 51 swings left and right so as not to interfere with the non-rotating chuck 35 and slides against the underside of the wafer W (FIG. 3(b)). Therefore, the brushes 51 move in the same sliding direction while being disposed at different positions along the sliding direction, which is the revolution direction. In other words, when the two brushes 51 slide on the wafer W, the other brush 51 moves to follow one brush 51. If the two brushes 51 are paired, the above swing is performed so that the pair moves equally left and right with respect to the virtual line L5.

When the cup 3 moves from the rear position to the front position while the brush 51 is oscillating in this manner and the entire center is slid and cleaned by the brush 51 (Figure 3(c)), the movement of the cup 3, the discharge of cleaning liquid from the nozzle 36, and the rotation and revolution of the brush 51 stop.

Each brush 51 descends to a non-processing position, the cup 3 moves to a lower position, the center of the underside of the wafer W is suction-held by the spin chuck 12, and the suction-holding of the wafer W by the non-rotating chuck 35 is released. Then, air is discharged from the air knife 18, cleaning liquid is discharged from the nozzle 36, and the wafer W is rotated by the spin chuck 12. As described above, since the wafer W moves together with the cup 3, the position where the cleaning liquid is discharged at this time is the peripheral portion of the wafer W. When each brush 51 revolves and is positioned, for example, on the right side of the imaginary line L5, it rises and rotates (spins) to the processing position and is pressed against the peripheral portion of the underside of the wafer W, cleaning the peripheral portion of the wafer W. In other words, the brushes 51 slide in the same sliding direction with the rotation direction of the wafer W as the sliding direction, and processing is performed. At this time, each brush 51 is positioned at a different position from each other in the radial direction of the wafer W.

After the brush 51 is pressed against the wafer W, the wafer W rotates one or more times until cleaning of the entire peripheral portion of the wafer W is complete. When cleaning of the entire underside of the wafer W is complete, including the cleaning performed while the wafer W was held by the non-rotating chuck 35, the rotation of the wafer W and the rotation of the brush 51 each stop. The brush 51 descends, pivots, and ascends, separating it from the wafer W and passing under the cup 3 to return to the waiting area 26, and the discharge of cleaning liquid from the nozzle 36 also stops. The wafer W is then handed over to the transfer mechanism by the raising and lowering of the support pins 16, and transferred from the cleaning device 1.

According to this cleaning apparatus 1, when cleaning the central portion of the lower surface of the wafer W, the brushes 51A and 51B pressed against each other simultaneously as described above are moved in the same sliding direction so as to oscillate.
Therefore, even if the rotation amount of the stage 41 for revolving the brush 51 is relatively small, the brushes 51A and 51B can reach the desired positions on the right side and the left side of the center of the wafer W, respectively, to perform cleaning. By suppressing the rotation amount of the stage 41 required for cleaning in this way, cleaning of the center of the lower surface of the wafer W can be completed quickly. In addition, cleaning can be completed quickly by simultaneously cleaning the peripheral portion of the wafer W by each brush 51 during processing of the peripheral portion of the wafer W. As a result, the cleaning apparatus 1 can obtain a high throughput. In addition, when cleaning the peripheral portion of the lower surface of the wafer W, each brush 51 is disposed at a different position in the radial direction of the rotating wafer W. Therefore, a wide range of the peripheral portion of the wafer W is cleaned simultaneously, and a high throughput can be obtained more reliably.

In the above processing example, when cleaning the peripheral portion of the underside of the wafer W, the wafer W is rotated clockwise and each brush 51 is rotated counterclockwise, i.e., the wafer W and the brushes 51 are rotated in opposite directions to each other, thereby applying a relatively strong load to the underside of the wafer W and achieving a high cleaning effect. However, this is not the only rotational relationship, and each brush 51 can be rotated (spinned) in any direction. For example, in the example shown in Figure 4, unlike the example shown in Figure 3, brush 51B is rotated clockwise. Note that brush 51A may also be rotated (spinned) in any direction.

In addition, in the above processing example, when cleaning the peripheral portion of the wafer W, each brush 51 is not revolved but is fixed in position relative to the rotating wafer W, but the position is not limited to being fixed in this manner. In the example shown in FIG. 5, each brush is revolved counterclockwise from a state in which imaginary line L5 is located between brushes 51A and 51B, and the area of the peripheral portion of the rotating wafer W that is rubbed by brush 51 is moved from a position closer to the center of the wafer W to the peripheral edge. The peripheral portion of the wafer W may be cleaned by such an operation. Note that even when brush 51 is moved in this manner, different radial positions of the wafer W are individually cleaned by brush 51, so that processing of the peripheral portion can be completed quickly.

Second Embodiment
The cleaning device 1A according to the second embodiment will be described with reference to the side view shown in FIG. 6. The cleaning device 1A includes a cleaning processor 6 instead of the cleaning processor 4, and the following description will focus on the differences between the cleaning processor 6 and the cleaning processor 4. As described above, the stage 41 rotates around the central axis R1, but the rotation mechanisms 43 and 44 are not provided on the stage 41, and the support arm 61 extends horizontally from the stage 41. A circular stage 63 is provided horizontally above the rotation mechanism 62 provided at the tip of the support arm 61. The stage 63 can be rotated around the vertical central axis R2 by the rotation mechanism 62. In this embodiment, the rotation direction of the stage 63 is clockwise in a plan view.

Rotation mechanisms 43A and 44A, which correspond to the rotation mechanisms 43 and 44 already described, are provided above the stage 63. These rotation mechanisms 43A and 44A are connected to the brushes via shafts 52, and can rotate each brush in the same manner as in the first embodiment. In addition, the stage 63 can raise and lower the rotation mechanisms 43A and 43B individually, moving each brush between a processing position and a non-processing position.

The brush connected to the rotating mechanism 43A is the brush 51 as in the first embodiment. Instead of the brush 51, the brush 53 is connected to the rotating mechanism 44A. In each embodiment from this second embodiment onwards, the brush 51 is the first brush and the brush 53 is the second brush. The brush 53 is configured in a circular shape of the same size as the brush 51 in a plan view, and rotates (spins) around its center in a plan view by the rotating mechanism 44A. However, when comparing the elasticity of the brushes 51 and 53, the elasticity of the brush 53 is lower than that of the brush 51. The brush 53 polishes the lower surface of the wafer W by sliding the sliding surface of its upper end against the wafer W, and scrapes off foreign matter adhering to the wafer W. Note that, for example, when the sliding surface of the brush 51 against the wafer W is made of resin, the sliding surface of the brush 53 against the wafer W has finer unevenness than the sliding surface of the brush 51.

In this second embodiment, the movement of brushes 51 and 53 is controlled so that brush 51 slides over the area on the underside of wafer W that brush 53 has already slid over, and the shavings generated on the underside of wafer W by the sliding of brush 53 are removed by the sliding of brush 51. Note that in this specification, polishing processing is included in cleaning processing, but for ease of explanation, a distinction may be made between the processing by pressing brush 53 against the wafer and the processing by pressing brush 51 against the wafer, with the processing being referred to as polishing and the processing being referred to as cleaning. Note that in this second embodiment, both brushes 51 and 53 rotate (spin) counterclockwise.

In this embodiment, the stage 41 rotates around the central axis R1 to move the brushes 51 and 53 between the waiting area 26 and the underside of the wafer W, and the brushes 51 and 53 revolve around the central axis R2 of the stage 63 during processing of the wafer W. Therefore, the central axis R2 is the revolution axis (rotation axis) of the brushes 51 and 53. In a plan view, the centers of the brushes 51 and 53 are located on the diameter of the stage 63 and are equidistant from the central axis R2. In addition, the brushes 51 and 53 are provided close to each other in a plan view, and the diameter of the brushes 51 and 53 is approximately the same as the radius of the stage 63. The diameter of the circle formed by the revolution orbit of the brushes 51 and 53 (revolution orbit around the central axis R2) is smaller than the radius of the wafer W, and the brushes 51 and 53 revolve (revolve) so that this revolution orbit overlaps with the peripheral portion of the wafer W when processing the peripheral portion of the wafer W described below.

The operation of the cleaning device 1A will be described with a focus on the differences from the cleaning device 1 using Figures 7 to 9. In Figures 7 to 9, imaginary lines L3 to L5 are shown as in Figure 3, but imaginary lines L4 and L5, which were drawn to pass through the central axis R1 to indicate the position of the revolution axis of the brush during processing in Figure 3, are drawn to pass through the central axis R2 instead of through the central axis R1.

When the wafer W is transported to the cleaning device 1A, the wafer W is suction-held on the non-rotating chuck 35. Then, as the stage 41 rotates, the brushes 51 and 53 move from the waiting area 26 to below the wafer W, and the central axis R2 (the revolution axis of the brush) of the stage 63 and the center of the spin chuck 12 are aligned in the direction of forward and backward movement of the cup 3 (FIG. 7(a)). Next, the cup 3 moves to the rear position, and while the brush 51 remains in the non-processing position, the brush 53 rotates (spins) and rises to the processing position, where it is pressed against the underside of the wafer W. Meanwhile, a cleaning liquid is ejected from the nozzle 36 and supplied to the center of the underside of the wafer W.

The brush 53 revolves as the stage 63 rotates, and the center of the underside of the wafer W is polished in the circumferential direction (FIG. 7(b)). After the brush 53 is pressed against the wafer W, the stage 63 rotates once, and when the entire center of the wafer W is polished, the brush 53 stops rotating and descends to a non-processing position, while the brush 51 rotates (spins) and rises to the processing position and is pressed against the underside of the wafer W. As the stage 63 continues to rotate, the center of the underside of the wafer W is cleaned in the circumferential direction (FIG. 7(c)). After the brush 51 is pressed against the wafer W, the stage 63 rotates once, and when the entire center of the wafer W is cleaned, the brush 51 stops rotating and descends to a non-processing position. In addition, the discharge of the cleaning liquid from the nozzle 36 is temporarily stopped.

After that, the cup 3 moves to the forward position and then moves toward the lowered position, so that the spin chuck 12 holds the wafer W instead of the non-rotating chuck 35 (FIG. 8(a)). Next, the stage 63 rotates, so that the centers of the brushes 51 and 53 are aligned with the imaginary line L5 in a plan view, and the brush 53 is positioned closer to the center of the wafer W than the brush 51. Meanwhile, as the wafer W rotates, the nozzle 36 resumes ejecting the cleaning liquid, and the cleaning liquid is supplied to the peripheral portion of the wafer W.

Then, while the brush 51 is in the non-processing position, the brush 53 rotates (spins) and rises to the processing position, and when it is pressed against the underside of the wafer W, the stage 63 rotates and the brush 53 moves toward the peripheral edge of the wafer W (FIG. 8(b)). The rotation of the wafer W causes the brush 53 to slide along the circumference of the wafer W, and the rotation of the stage 63 causes the brush 53 to revolve, so that the sliding position moves toward the peripheral edge of the wafer W. Note that this processing of the wafer W by only the brush 53 of the brushes 51 and 53 corresponds to the first sliding step. Note that the collective (simultaneous) rotation of the brushes 51 and 53 by the rotation of the stage 63 corresponds to the rotation step. Then, just before the stage 63 rotates half a turn after the brush 53 moves to the processing position, the brush 51 rotates (spins) and moves toward the processing position. When brush 53 starts to descend toward the non-processing position and stage 63 has rotated half a turn, brushes 51 and 53 are both pressed against wafer W, and the centers of brushes 51 and 53 in plan view are positioned on imaginary line L5 (FIG. 8(c)). In other words, the pressing force of brush 53 remains on wafer W, and the pressing force of brush 51 is applied to wafer W. By moving brush 53 to this position, it reaches the peripheral edge of wafer W, and polishing of the entire peripheral portion of wafer W is completed.

Furthermore, the stage 63 rotates, so that the brush 51 moves toward the peripheral edge of the wafer W. Meanwhile, the brush 53 moves away from the wafer W and descends toward the non-processing position (FIG. 9(a)). Then, after the brush 51 is positioned at the processing position, the stage 63 rotates half a turn, and the centers of the brushes 51 and 53 in a plan view are aligned with the imaginary line L5, completing cleaning of the entire peripheral portion of the wafer W by the brush 51 (FIG. 9(b)). Note that this processing of the wafer W by only the brush 51 of the brushes 51 and 53 corresponds to the second sliding step. The brush 51 descends to the non-processing position, the rotation of the brush 51 stops, the discharge of the cleaning liquid from the nozzle 36 stops, and the rotation of the wafer W stops, and the wafer W is unloaded from the cleaning apparatus 1A.

In this way, in the cleaning apparatus 1A, when processing the peripheral portion of the wafer W, the brushes 51 and 53 are positioned at different positions in the revolution direction, which is the sliding direction relative to the wafer W. These brushes 51 and 53 are pressed against the wafer W at the same time, and timing is set so that polishing and cleaning are performed in parallel, so that the polishing and cleaning processes are performed quickly. Note that, when processing the center portion of the wafer W, it has been described that the brush 53 moves to a non-processing position, and then the brush 51 moves to a processing position; however, as in processing the peripheral portion, the brushes 51 and 53 may be pressed against the wafer W at the same time when switching between the brushes 51 and 53 to be used.

As described above, brushes 51 and 53 are pressed simultaneously when processing the peripheral portion of wafer W. However, suppose that brush 53 is moved away from wafer W and then brush 51 is pressed against wafer W with a gap therebetween. In this case, the relatively large pressing force applied by brush 53 disappears as brush 53 is moved away, causing the attitude of wafer W to change. This change in attitude and the centrifugal force of the rotation of wafer W may cause the peripheral portion of wafer W to vibrate up and down. Such vibration may damage the resist film formed on the surface of wafer W, and may affect the yield of semiconductor devices. By pressing brushes 51 and 53 simultaneously, the occurrence of such defects can be suppressed.

Note that FIG. 10 is a schematic diagram showing the brushes 51 and 53 when they are pressed against the wafer W together as shown in FIG. 8(c). As described above, the brushes 51 and 53 rotate counterclockwise, i.e., in the same direction. Due to the rotation of the brush 53, the cleaning liquid containing the shavings generated by the polishing of the brush 53 scatters toward the brush 51. In the figure, the cleaning liquid toward the brush 51 is indicated by an arrow as 71. On the other hand, as the brush 51 rotates in the same direction as the brush 53, the cleaning liquid (indicated by an arrow as 72) scatters from the brush 51 toward the brush 53 with a relatively strong vector. Therefore, the vector of the cleaning liquid 71 containing the shavings is canceled out or weakened by the vector of the cleaning liquid 72. Therefore, the adhesion of the shavings to the brush 51 is suppressed. Therefore, the frequency of cleaning the brush 51 in the standby area 26 can be reduced, and the operating efficiency of the cleaning device 1B can be increased. The operating efficiency can also be increased by rotating both brushes 51 and 53 clockwise. In order to more reliably prevent shavings from adhering to brush 51, the rotation speed of brush 51 when they are both pressed against wafer W may be made faster than the rotation speed of brush 53 so that the vector of cleaning liquid 72 becomes larger.

Third Embodiment
The cleaning apparatus 1B according to the third embodiment will be described with reference to FIG. 11, focusing on the differences from the cleaning apparatus 1 according to the first embodiment. The cleaning apparatus 1B includes a cleaning processing unit 4 like the cleaning apparatus 1 according to the first embodiment, but includes a brush 53 instead of the brush 51A. In the cleaning apparatus 1B, the central part of the lower surface of the wafer W is polished by using the brush 53 and the brush 51 in order, whereas the central part of the wafer W is polished by oscillating the brush while the wafer W is held by the non-rotating chuck 35 as described in the first embodiment. Specifically, only the brush 53 of the brushes 51 and 53 is moved to a processing position, and the brush 53 is polished by rotating (rotating) and oscillating (revolving) like the brush 51 of the first embodiment. Thereafter, only the brush 51 of the brushes 51 and 53 is moved to a processing position, and the brush 51 is rotated (rotating) and oscillated for cleaning. Note that the cup 3 is moved in the front-rear direction during processing by the brushes 51 and 53 so that the entire central part of the wafer W is processed like the first embodiment. Specifically, for example, during processing by the brush 53, the brush 54 is moved from the rear position to the front position, and then returned to the rear position again, and during processing by the brush 51, the brush 54 is moved from the rear position to the front position.

After the above processing of the center of the underside of the wafer W, the wafer W is held by the spin chuck 12 and the peripheral portion of the underside of the wafer W is processed. FIG. 11 shows the peripheral processing process. First, in a plan view, the center of the brush 53 is positioned on the imaginary line L5. Then, the wafer W is rotated, and the brushes 51 and 53 are raised from the non-processing position to the processing position and rotated to press against the wafer W (FIG. 11(a)). Then, the stage 41 rotates clockwise, and the brush 53 revolves toward the peripheral edge of the wafer W, while the brush 51 revolves toward the peripheral edge of the wafer W so as to follow the brush 53. Therefore, the brush 51 moves on the wafer W in a plan view so as to follow the movement path of the brush 53 (FIG. 11(b)). As a result, the area to be polished moves toward the peripheral edge of the rotating wafer W, and the area to be cleaned moves toward the peripheral edge of the wafer W following the movement of the polished area.

When the brush 53 is positioned at the peripheral edge of the wafer W and polishing of the entire peripheral edge of the wafer W is completed, the brush 53 returns to the non-processing position and stops rotating. The brush 51 continues to revolve due to the rotation of the stage 41, and when the brush 51 is positioned at the peripheral edge of the wafer W and cleaning of the entire peripheral edge of the wafer W is completed (Figure 11 (c)), the brush 51 returns to the non-processing position and stops rotating.

In the above-mentioned cleaning apparatus 1B, the brushes 51 and 53 are simultaneously pressed against the peripheral portion of the underside of the wafer W and slide in the direction of rotation of the wafer W, thereby simultaneously polishing and cleaning, and therefore the time required for processing can be shortened and a high throughput can be obtained. In the cleaning apparatus 1B, during processing of the peripheral portion of the wafer W, the stage 41 rotates in the direction already described, causing the brushes 51 and 53 to revolve toward the upstream side of the rotation direction of the wafer W. By moving the brushes 51 and 53 against the rotation direction of the wafer W in this way, the frictional force between the brushes 51 and 53 and the wafer W can be increased, and the polishing power of the brush 53 and the cleaning power of the brush 51 can be increased.

(First Modification of the Third Embodiment)
A cleaning apparatus 1C according to a first modified example of the third embodiment is shown in FIG. 12. The cleaning apparatus 1C differs from the cleaning apparatus 1B in that the positions of the brushes 51 and 53 are reversed. That is, compared to the cleaning apparatus 1 of the first embodiment, the brush 53 is provided instead of the brush 51B. The processing of the peripheral portion of the lower surface of the wafer W by the cleaning apparatus 1C is performed in a manner substantially similar to that of the cleaning apparatus 1B, but the rotation direction of the stage 41 is counterclockwise, unlike that of the cleaning apparatus 1B, so that the brushes 53, 51 move to the peripheral edge of the wafer W in that order. As shown in the examples of the cleaning apparatuses 1B and 1C, the revolution direction of the brushes 51, 53 may be either clockwise or counterclockwise, and the arrangement of the brushes 51, 53 can be appropriately changed according to the rotation direction.

(Second Modification of the Third Embodiment)
A cleaning device 1D according to a second modification of the third embodiment is shown in Fig. 13. In this cleaning device 1D, the stage 41 is not provided, and stages 45A and 45B are provided side by side on the left and right sides behind the air knife 18. The stages 45A and 45B are configured to be rotatable about rotation axes R3 and R4 along the vertical direction, respectively, and each include an arm 46A and 46B extending horizontally. An elevation mechanism is provided at the tip of each of the arms 46A and 46B, and rotation mechanisms 43A and 44A are provided on the elevation mechanisms. As described above, brushes 51 and 53 are connected to the rotation mechanisms 43A and 43B, respectively.

The above rotation axes R3 and R4 therefore form the revolution axes (pivot axes) for brushes 51 and 53, respectively. In this manner, a configuration in which an individual revolution axis is provided for each of brushes 51 and 53 may be adopted. In embodiments other than the third embodiment, multiple brushes may also revolve around different revolution axes, but it is advantageous to have multiple brushes revolve collectively around a common revolution axis, as in the first embodiment, etc., since this simplifies the device configuration and reduces the manufacturing costs of the device.

Fourth Embodiment
A cleaning device 1E according to the fourth embodiment will be described with reference to FIG. 14(a). The difference between the cleaning device 1D and the cleaning device 1B according to the third embodiment is that a total of three brushes, brushes 51A, 51B, and brush 53, are provided on the periphery of the stage 41. In plan view, the brushes 51A, 53, and 51B are provided in the order of brushes 51A, 51B, and 53 along the circumferential direction of the stage 41, and these brushes 51A, 51B, and 53 are provided on the periphery of the stage 41. In plan view, the brush 53 is disposed close to the brushes 51A and 51B, and the centers of the brushes 51A, 51B, and 53 are located at equal distances from the central axis R1 of the stage 41. The stage 41 in this fourth embodiment is provided with three rotating mechanisms in the circumferential direction that can be raised and lowered in the same manner as the rotating mechanism 43 or 44 described above, and the brushes 51A, 51B, and 53 are connected to the rotating mechanisms, so that they can rotate (spin) and rise and fall independently of each other.

In the cleaning apparatus 1E, similar to the cleaning apparatus 1B of the third embodiment, the cleaning brush 51 and the polishing brush 53 are swung by switching the rotation direction of the stage 41, thereby processing the center of the underside of the wafer W. However, the elevation of each of the brushes 51A and 51B is controlled so that one of the brushes corresponding to the revolution direction (rotation direction of the stage 41) is pressed against the wafer W, and brush 53 is the first of the brushes that slide over the wafer W.

Specifically, when the wafer W is held by the non-rotating chuck 35, the center of the brush 53 overlaps with the imaginary line L5 in a plan view, for example as shown in FIG. 14(a), and the brushes are positioned in a non-processing position and rotate on their axes. Then, the brushes 53 and 51A rise and move to the processing position. Then, the stage 41 rotates counterclockwise in a plan view, and the brush 53 moves to a position shifted to the left of the imaginary line L5, and the brush 51A moves following the brush 53 (FIG. 14(b)). In other words, of the brush array composed of the brushes 51A, 53, and 51B arranged in the rotation direction (revolution direction), the brush 51B is positioned lower than the other brushes and is treated as an unused brush, and the first cleaning process is performed.

Then, when the brush 53 moves away from the virtual line L5 by a predetermined amount, the rotation direction of the stage 41 is switched to clockwise in a plan view. When the rotation direction is switched in this way, the brush 51A moves down to a non-processing position, and the brush 51B moves up to a processing position. Then, due to the rotation of the stage 41, the brush 53 moves toward a position shifted to the right side of the virtual line L5, and the brush 51B moves following the brush 53 (FIG. 14(c)). In other words, in the above brush array, the brush 51A is placed at a lower position than the other brushes, and a second cleaning process is performed to make it an unused brush. After that, when the position of the brush 53 moves away from the virtual line L5 by a predetermined amount, the rotation direction of the stage 41 is switched to counterclockwise in a plan view. When the rotation direction is switched in this way, the brush 51A moves to a non-processing position and the brush 51B moves to a processing position, and due to the rotation of the stage 41, the brush 53 moves toward a position shifted to the left side of the virtual line L5. This movement and raising and lowering of the brush 53 is repeated to process the center of the wafer W.

As described above, this cleaning apparatus 1E can simultaneously polish and clean the central portion of the underside of the wafer W, achieving high throughput. Although detailed description of the processing of the peripheral portion of the underside of the wafer W will be omitted, for example, processing can be performed by using one of the two brushes 51 (51A, 51B) and brush 53 and sliding each brush against the wafer W as shown in the third embodiment.

(Modification of the fourth embodiment)
15A, the cleaning apparatus 1F according to the modified example of the fourth embodiment is different from the cleaning apparatus 1E in that the cleaning apparatus 1F is provided with two brushes 53 (referred to as 53A and 53B) and one brush 51. The brushes 53A and 53B are provided at the positions where the brushes 51A and 51B are provided in the cleaning apparatus 1E, respectively, and the brush 51 is provided at the position where the brush 53 is provided in the cleaning apparatus 1D. Therefore, the brushes are provided on the periphery of the stage 41 in the order of 53B, 51, and 53A in a plan view.

When processing the center of the underside of the wafer W, the rotation direction of the stage 41 is switched as in the cleaning apparatus 1E to oscillate each brush. The lifting and lowering operation of each brush is controlled so that the brush 53 is at the front of the brushes that slide on the underside of the wafer W. Specifically, as shown in FIG. 15(b), when the stage 41 rotates counterclockwise, the brushes 53B and 51 are located at the processing position, while the brush 53A is located at the non-processing position. That is, of the brush array configured with the brushes 53A, 51, and 53B arranged in the rotation direction (revolution direction), the brush 53A is placed at a lower position than the other brushes, and a first cleaning process is performed to make it an unused brush. Then, as shown in FIG. 15(c), when the stage 41 rotates clockwise, the brushes 53B and 51 are located at the processing position, while the brush 53B is located at the non-processing position. That is, of the brush array described above, the brush 53B is placed at a lower position than the other brushes, and a second cleaning process is performed to make it an unused brush.

In this cleaning apparatus 1E, polishing and cleaning are performed simultaneously, resulting in a high throughput. In addition, since brush 53 polishes wafer W, it receives a larger frictional force from wafer W when sliding compared to brush 51, and is therefore more susceptible to deterioration. However, in cleaning apparatus 1E, two brushes 53 are used in a switched manner as described above, which has the advantage of extending the life of brush 53 and reducing the frequency with which brush 53 needs to be replaced.

Fifth Embodiment
16(a) and 16(b) show a cleaning device 1G according to a fifth embodiment, in which a brush 55 is provided instead of the brush 53 of the cleaning device 1B according to the third embodiment described in FIG. 11, and the brushes 51 and 55 correspond to the first and second brushes, respectively, in the cleaning device 1G. The brush 55 is used for both polishing and cleaning. Referring to the perspective view of FIG. 17, the brush 55 has a circular and horizontal base 56, and a shaft 52 is connected to the center of the base 56 from below. The brush 55 is connected to the above-mentioned rotating mechanism 44 via the shaft 52, and can rotate in the circumferential direction and move up and down.

A roughly annular polishing section 57 is provided on the peripheral portion of the base 56 along the peripheral portion. The polishing section 57 is configured by polishing members that are arc-shaped in plan view and spaced apart in the circumferential direction of the base 56, and a groove 59 for discharging cleaning liquid is formed between the polishing members. The polishing section 57 corresponds to the polishing brush 53 described above, and the upper end surface of the polishing section 57 forms a sliding surface 57A (first sliding surface) against the wafer W. The polishing section 57 is, for example, sheet-shaped, but for convenience, it is shown thicker in FIG. 16 than in FIG. 17. In addition, a ring-shaped cleaning section 58 is provided along the circumference of the base 56, surrounded by the polishing section 57. The cleaning section 58 corresponds to the brush 51 described above, and the upper end surface of the cleaning section 58 forms a sliding surface 58A (second sliding surface) against the wafer W. Like the brush 51, the cleaning part 58 has elasticity, and when the brush 55 is not pressed against the wafer W and the cleaning part 58 is not receiving any pressing force from the wafer W, the sliding surface 58A is located above the sliding surface 57A. FIG. 17 shows the cleaning part 58 in a state where it is not receiving the pressing force, and FIG. 16 also shows the cleaning part 58 by the dotted line when it is not receiving the pressing force.

When the brush 55 is pressed against the wafer W, the cleaning portion 58 deforms due to its elasticity, thereby aligning the heights of the sliding surfaces 57A, 58A. When polishing the wafer W, the brush 55 is located at a polishing processing position (first position) where both sliding surfaces 57A, 58A are pressed against the underside of the wafer W, and when cleaning the wafer W, the brush 55 is located at a cleaning processing position (second position) where only the sliding surface 58A is pressed against the underside of the wafer W.

The processing by the cleaning apparatus 1G will be described with reference to FIG. 16, focusing on the differences from the cleaning apparatus 1B. First, when processing the center of the underside of the wafer W, the brush 55 located at the polishing processing position rotates and oscillates to perform polishing (FIG. 16(a)). That is, polishing is performed by the brush 55 located at the polishing processing position instead of the brush 53. At this time, the brush 51 is located at the non-processing position. After this polishing, the brush 51 is positioned at the processing position, and the brush 55 is lowered to the cleaning processing position in a placement process. Then, the center of the underside of the wafer W is cleaned by the oscillation of the brushes 51 and 55 (FIG. 16(b)). When the brushes 51 and 55 are pressed against the wafer W to perform cleaning in this way, the upper surface of the brush 51 (sliding surface against the wafer W) is lower than the sliding surface 58A when no pressing force from the wafer W is applied, and higher than the sliding surface 57A of the polishing portion 57. By configuring brush 55 to form this height positional relationship, it is possible to perform the polishing described above, and both brushes 51 and 55 can be used during cleaning, so the number of brushes installed in the device can be reduced while the cleaning process can be completed quickly.

Although only the processing of the center of the wafer W has been specifically described, when processing the peripheral portion of the underside of the wafer W, the processing described as being performed by the brush 53 in the cleaning device 1B can be performed by the brush 55 arranged at the polishing processing position. The polishing processing performed by the brush 53 in each of the other embodiments may also be performed by the brush 55 arranged at the polishing processing position. Note that although the sliding surfaces of the brushes 51 and 53 against the wafer W have been shown as being circular, they may also be annular, like the polishing portion 57 and cleaning portion 58 of the brush 55.

In each of the embodiments described above, the film formed on the surface of the wafer W is a resist film, but the back surface of the wafer W can be cleaned regardless of the type of film formed. In addition, in each embodiment, each brush has been described as rotating when sliding against the wafer W, but cleaning (including polishing) can be performed by sliding the brush against the wafer W by rotating the wafer W and/or revolving the brush without such rotation. Therefore, the brush does not need to rotate. In addition, the number of brushes is not limited to the examples described above, and cleaning can be performed with any number of brushes, and cleaning (including polishing) can be performed by pressing three or more brushes against the wafer W simultaneously.

In addition, in each embodiment in which the cleaning device is equipped with brush 53, both the peripheral and central portions of the wafer W are polished, but this is not limited to such a processing example. For example, the central portion may be only cleaned, and only the peripheral portion may be polished and cleaned. In addition, the waiting portion 25 is not limited to the arrangement example shown in FIG. 1, etc., and may be located in a position that overlaps with the area in which the brushes 51 and 53 rotate by the stage 41, and may be located, for example, toward the rear of the device.

The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The above embodiments may be omitted, substituted, modified, or combined in various ways without departing from the scope and spirit of the appended claims.

W Wafer 13 Spin chuck 51, 53 Brush

Claims (16)

a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
The first brush has a higher elasticity than the second brush,
the cleaning step includes a step of sliding the first brush and the second brush against the substrate such that the first brush follows the second brush;
The method includes a step of rotating an array of brushes arranged in the order of the first brush, the second brush, and the first brush in the rotation direction around a rotation axis extending in the vertical direction, or in the order of the second brush, the first brush, and the second brush in the rotation direction, in a clockwise direction and a counterclockwise direction in a plan view,
The washing step comprises:
a first cleaning step of positioning one of the brushes in the array as an unused brush at a lower position than the other brushes during the clockwise revolution of the array, and sliding the second brush and a first brush following the second brush against the substrate by the revolution;
a second cleaning step in which one brush of the array, which is different from the unused brush in the first cleaning step, is placed as an unused brush at a lower position than the other brushes while the array is rotating in the counterclockwise direction, and the second brush and a first brush following the second brush are slid on the substrate;
A method for cleaning a substrate comprising: a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
a first sliding step of pressing only the first brush out of the first brush and the second brush against a lower surface of the substrate and sliding the brush;
a second sliding step of pressing only the second brush out of the first brush and the second brush against the lower surface of the substrate and sliding the brush against the lower surface of the substrate;
The cleaning step includes a step of lowering the first brush and raising the first brush after performing the first sliding step and pressing the second brush against the substrate while the first brush is kept pressed against the substrate. a rotating step of rotating the first brush and the second brush together around a rotation axis extending in a vertical direction, with a rotation orbit being a circle overlapping the substrate held by the substrate holding unit,
each of the cleaning step, the first sliding step, and the second sliding step is performed during the turning step, and the sliding direction of the first brush and the second brush in the cleaning step is the turning direction;
3. The substrate cleaning method according to claim 2, wherein the first sliding step is a step of rotating the first brush along a first arc forming the circle while being pressed against the substrate, and the second sliding step is a step of rotating the second brush along a second arc that forms the circle while being pressed against the substrate and is different from the first arc. a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
the second brush includes a first sliding surface having a first height that slides against the substrate, and a second sliding surface that is elastic and is higher than the first height;
a step of raising and lowering the second brush between a first position where the first sliding surface and the second sliding surface are in contact with the substrate and a second position where only the second sliding surface of the first sliding surface and the second sliding surface is in contact with the substrate,
the cleaning step includes a positioning step of positioning the first brush at a position where a sliding surface of the first brush slides against the substrate while the second brush is located at the second position;
A substrate cleaning method, wherein the sliding surface of the first brush in the positioning step is lower than the second sliding surface when no pressing force is applied to the substrate, and higher than the first sliding surface . a step of holding a lower surface of a substrate having a film formed on an upper surface thereof by a substrate holding part;
a cleaning step of simultaneously pressing a first brush and a second brush against a lower surface of the substrate and sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate to clean the substrate;
Equipped with
a covering portion is provided to cover the first brush and the second brush from above,
a step of rotating the first brush and the second brush together about a rotation axis extending in a vertical direction and moving the first brush and the second brush between a waiting area below the covering portion where the first brush and the second brush are kept waiting and a position where the first brush and the second brush are each pressed against the substrate;
A method for cleaning a substrate comprising: a cylindrical body is provided surrounding a side periphery of the substrate held by the substrate holding portion;
If the direction in which the center of the substrate held by the substrate holder and the pivot shaft are aligned is defined as the front-rear direction,
The left end of the waiting area does not protrude leftward beyond the left end of the cylindrical body,
The method for cleaning a substrate according to claim 5 , wherein a right end of the waiting area does not protrude rightward beyond a right end of the cylindrical body. A substrate cleaning method according to any one of claims 1 to 6, wherein the cleaning step includes a step of disposing the first brush and the second brush at different positions in the radial direction of the substrate, rotating each of the brushes and sliding them against the substrate. The first brush has a higher elasticity than the second brush,
The washing step comprises:
8. The method for cleaning a substrate according to claim 1, further comprising a rotating step of rotating the first brush and the second brush in the same direction in a plan view and pressing the first brush and the second brush against the lower surface of the substrate. The substrate cleaning method according to claim 8, wherein the rotating step includes a step of making the rotation speed of the first brush greater than the rotation speed of the second brush. a substrate holder for holding a lower surface of a substrate having a film formed on an upper surface thereof;
A first brush and a second brush;
a sliding mechanism for pressing a first brush and a second brush against a lower surface of the substrate and for cleaning the substrate by sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate;
Equipped with
The first brush has a higher elasticity than the second brush,
the sliding mechanism slides the first brush and the second brush relative to the substrate such that the first brush follows the second brush;
an array of brushes is provided around a rotation axis extending in a vertical direction, the first brush, the second brush, and the first brush being arranged in that order in the rotation direction, or the second brush, the first brush, and the second brush being arranged in that order in the rotation direction;
the sliding mechanism includes a rotating mechanism for rotating the array body clockwise and counterclockwise in a plan view, and a lifting mechanism for lifting and lowering the first brush and the second brush,
a substrate cleaning apparatus for cleaning a substrate by placing one brush of the array as an unused brush at a lower position than the other brushes during the clockwise rotation of the array, and sliding the second brush and a first brush following the second brush against the substrate as the array rotates , and by placing one brush of the array and different from the unused brush during the clockwise rotation as an unused brush at a lower position than the other brushes during the counterclockwise rotation of the array, and sliding the second brush and the first brush following the second brush against the substrate. a substrate holder for holding a lower surface of a substrate having a film formed on an upper surface thereof;
A first brush and a second brush;
a sliding mechanism for pressing a first brush and a second brush against a lower surface of the substrate and for cleaning the substrate by sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate;
Equipped with
the sliding mechanism includes a lifting mechanism for lifting and lowering each of the first brush and the second brush, and a first sliding state in which only the first brush of the first brush and the second brush is pressed against and slid on the lower surface of the substrate;
a second sliding state in which only the second brush of the first brush and the second brush is pressed against and slid on the lower surface of the substrate; and
a first brush being lowered and then raised between the first sliding state and the second sliding state, thereby forming a state in which the first brush is pressed against the substrate while the second brush is pressed against the substrate. a substrate holder for holding a lower surface of a substrate having a film formed on an upper surface thereof;
A first brush and a second brush;
a sliding mechanism for pressing a first brush and a second brush against a lower surface of the substrate and for cleaning the substrate by sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate;
Equipped with
the second brush includes a first sliding surface having a first height that slides against the substrate, and a second sliding surface that is elastic and is higher than the first height;
a lifting mechanism is provided for lifting the second brush between a first position where the first sliding surface and the second sliding surface are in contact with the substrate and a second position where only the second sliding surface of the first sliding surface and the second sliding surface is in contact with the substrate;
the sliding mechanism disposes the first brush at a processing position where a sliding surface of the first brush slides against the substrate while the second brush is located at the second position;
A substrate cleaning apparatus, wherein the sliding surface of the first brush at the processing position is lower than the second sliding surface when no pressing force is applied against the substrate and higher than the first sliding surface . a substrate holder for holding a lower surface of a substrate having a film formed on an upper surface thereof;
A first brush and a second brush;
a sliding mechanism for pressing a first brush and a second brush against a lower surface of the substrate and for cleaning the substrate by sliding the first brush and the second brush in the same sliding direction relative to the lower surface of the substrate;
a covering portion that covers the first brush and the second brush from above;
a rotation mechanism that rotates the first brush and the second brush together about a rotation axis extending in a vertical direction and moves the first brush and the second brush between a waiting area below the covering portion where the first brush and the second brush are kept waiting and a position where the first brush and the second brush are each pressed against the substrate;
A substrate cleaning apparatus comprising: a cylindrical body is provided surrounding a side periphery of the substrate held by the substrate holding portion;
If the direction in which the center of the substrate held by the substrate holder and the pivot shaft are aligned is defined as the front-rear direction,
The left end of the waiting area does not protrude leftward beyond the left end of the cylindrical body,
The substrate cleaning apparatus according to claim 13 , wherein a right end of the waiting area does not protrude rightward beyond a right end of the cylindrical body. the sliding mechanism disposes the first brush and the second brush at different positions in a radial direction of the substrate,
15. The substrate cleaning apparatus according to claim 10, further comprising a rotation mechanism for rotating the first brush and the second brush to slide on the substrate. The first brush has a higher elasticity than the second brush,
16. The substrate cleaning apparatus according to claim 10, further comprising a rotation mechanism for rotating the first brush and the second brush in the same direction in a plan view.

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