JP2001195731A - Device for washing plate-shaped work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a work from being rejected because of poor washing and to enhance washing efficiency by inspecting the surface of the work after washing and changing washing conditions when the number of poorly washed works is large. SOLUTION: A washing part 5 is constituted of an ultrasonic washing part 1, a scrubbing/washing part 2, a rinsing part 3 and a drying part 4. A surface inspecting part 6 is disposed additionally to the part 5. The work W after washing is transferred to the part 6 to inspect the work surface. When the number of poorly washed works W having particle defects and stain defects in surface defects detected at the part 6 increased, the washing conditions such as the pushing pressure of a roll brush 20 to the work W and the revolution speed of the brush 20 are changed by a controller 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention includes a step of scrubbing at least the surface of a circular or rectangular plate-like work such as a magnetic disk or a semiconductor wafer having a substrate made of metal or glass, using a brush. The present invention relates to a cleaning device for a plate-like work.

[0002]

2. Description of the Related Art For example, the steps of manufacturing a magnetic disk are roughly divided into a step of manufacturing a substrate and a step of forming a magnetic recording film on the surface of the substrate to manufacture a magnetic disk as a final product. . The former is the substrate stage,
The latter is called the media stage. Regardless of the processing stage, the work to be processed is a disk made of an annular thin plate, and the surface of the work is repeatedly polished at both the substrate stage and the media stage. Each time the polishing is completed, the work is washed and dried.

[0003] An extremely high level of cleaning accuracy of a work is required. Typical examples of the work cleaning method include ultrasonic cleaning and scrub cleaning. For ultrasonic cleaning, an ultrasonic cleaning tank equipped with an ultrasonic generator in a tank filled with pure water is used, and a work is immersed in this ultrasonic cleaning tank,
The dirt is removed from the surface of the work by microvibrating the work by the action of ultrasonic waves. In the scrub cleaning, a dirt on the surface of the work is removed by sliding a brush on the surface of the work while supplying a cleaning liquid containing a surfactant or the like to the surface of the work. The scrub cleaning may be performed by scrubbing the brush with a cleaning liquid, sliding the brush while the cleaning liquid is being showered, or performing both of them. In addition, as the shape of the brush, a circular rod-shaped roll brush, a disk-shaped or annular surface brush, or the like is used.

[0004] Here, the surface of the workpiece is classified into a case where minute foreign matters such as abrasive powder and dust are attached, and a case where organic substances are attached or spots are generated. Ultrasonic cleaning by ultrasonically oscillating the workpiece is effective in removing minute foreign matter, and scrub cleaning with a cleaning liquid also has the function of removing minute foreign matter, but is effective in removing adhering foreign matter such as stains. It is. Therefore, by combining the ultrasonic cleaning and the scrub cleaning, these stains can be substantially completely removed, and the cleaning accuracy of the work is remarkably improved. Subsequent processes after cleaning the work include rinsing with pure water and drying. Rinsing is generally performed by a shower, and spin drying is mainly used for drying. From the above, a cleaning mechanism for a workpiece made of a magnetic workpiece, a semiconductor wafer, or the like generally includes an ultrasonic cleaning section, a scrub cleaning section, a rinsing section, and a drying section.

The cleaning of the work is performed as a post-process of the polishing process, and a configuration in which the surface appearance of the work is inspected after the cleaning process is proposed in, for example, Japanese Patent Application Laid-Open No. 4-315815. Have been. In this known apparatus, both the front and back surfaces of the work are preferably polished by a work surface polishing apparatus, and then transferred to a cleaning device to clean the front and back surfaces of the work, and spin-dried after this cleaning. The appearance inspection device is installed at the latter stage of the cleaning device. After the work is dried, it inspects the polishing accuracy and the presence or absence of defects on the front and back surfaces of the work. Only the next step.

[0006]

In the above-mentioned prior art apparatus, the appearance inspection of the work is for verifying the polishing accuracy on the surface of the work. If a surface defect is present, whatever the type of the defect is, it is excluded from the system as a defective product. Here, in the case where the defect itself cannot be repaired, such as when the surface defect has large irregularities or scratches on the surface of the work, or there is a whole or partial distortion or deformation, if the cleaning is not complete, Included are surface defects that occur, that is, particle defects in which minute foreign substances (hereinafter, referred to as particles) remain, and stain defects, which are made of stains (hereinafter, referred to as stains) to which fixed foreign substances such as stains adhere. In other words, surface defects of the work include a defect of the work itself and a defect based on the cleaning accuracy. A work having a problem with the cleaning accuracy can be a nondefective product if the cleaning is performed completely again. As described above, in the prior art, at least a part of the workpieces that have been excluded as defective products can include those whose defects can be eliminated through a step of re-cleaning. There is a drop.

Of course, the cleaning apparatus always maintains an extremely high cleaning accuracy, and maintenance is performed so that cleaning failure does not occur. For example, in scrub cleaning, since the surface of a work is mechanically scrubbed using a brush, abrasion, settling, and the like of the brush occur during repeated use over a long period of time, resulting in reduced cleaning accuracy. Therefore, strict management is performed such that the pressing force of the brush on the work is adjusted before the cleaning accuracy is affected, and the brush is replaced as necessary. The timing of this type of maintenance is generally based on the operation time of the apparatus, that is, the number of workpieces that have been subjected to the cleaning process.

However, abrasion and set of the brush do not always depend only on the number of processed sheets. The cleaning ability of the brush may be reduced before reaching the preset operation time, and the brush may still have sufficient cleaning ability even after the operation time. If the cleaning performance of the brush is worn or sagged earlier than the scheduled maintenance timing, the cleaning accuracy is reduced, and the number of defective products in the subsequent surface appearance inspection process is increased. It is also useless to replace the brush, even though the brush still maintains sufficient cleaning capacity.

The present invention has been made in view of the above points, and by performing a surface inspection on a cleaned work, it is possible to eliminate a work caused by a defective cleaning of the cleaned work. Is to minimize as much as possible.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for cleaning the surface of a plate-like work.
A cleaning unit including one or more cleaning steps and a drying step of drying the work after cleaning, a surface inspection unit for performing a defect inspection of the surface of the work after cleaning and drying, and a work based on a detection result of the surface inspection unit And a controller for changing a cleaning condition in the cleaning unit when the cleaning accuracy is determined to be decreased and the cleaning accuracy is detected to be reduced.

Here, the cleaning step of the cleaning section is controlled by the controller when the brush includes a scrub cleaning step in which at least the brush is brought into contact with the front and back surfaces of the work and the brush is rotated to perform the scrub cleaning. The cleaning condition is at least one or both of the pressing force of the brush against the work and the rotation speed thereof. The surface defect items detected by the surface inspection unit include defects caused by cleaning conditions, that is, at least the presence or absence of attached foreign matters and fixed foreign matters on the surface. It is set so that when a predetermined number is detected, it is determined that the cleaning accuracy has decreased.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; First, as is clear from FIG. 1, the basic configuration of the work cleaning apparatus includes a cleaning unit 5 including an ultrasonic cleaning unit 1, a scrub cleaning unit 2, a rinsing unit 3, and a drying unit 4. Have. Moreover, the cleaning unit 5 is provided with a surface inspection unit 6, and the cleaned work W is transferred to the surface inspection unit 6 to detect the presence or absence of a surface defect. In addition, a loader unit 7 is disposed upstream of the ultrasonic cleaning unit 1, and an unloader unit 8 is disposed downstream of the surface inspection unit 6. Loader section 7
In the unloader section 8, the work W is stored in a cassette. In the unloader section 8, as a result of the surface inspection by the surface inspection section 6, the work W is classified into three categories and stored in the cassette. Classification shall be non-defective, defective and defective cleaning. The classification is not limited to this, and non-defective products may be further classified, or when the occurrence rate of defective products other than defective cleaning products is low, the defective cleaning products and other defective products may be classified into the same classification. . Further, in the drawing, reference numeral 10 denotes a controller for controlling the cleaning mechanism based on an output signal from the surface inspection unit 6.

The ultrasonic cleaning section 1 constituting the cleaning section 5 has an ultrasonic cleaning tank 11 which contains pure water therein and has an ultrasonic generator 12 installed at the bottom thereof. Have been. Therefore, the inside of the ultrasonic cleaning tank 11 is always vibrated minutely by the ultrasonic waves generated by the ultrasonic generator 12, and when the work W is immersed in the ultrasonic cleaning tank 11, it is vibrated by the ultrasonic waves, Particles adhering to the surface are released from the surface of the work W to extremely small particles. The ultrasonic cleaning of the work W is performed in this manner.

Next, the scrub cleaning section 2 is provided with a pair of roll brushes 20 as shown in FIG. These two roll brushes 20 are each formed of an annular sponge or the like fixed to the outer peripheral portion of the rotating shaft 21. The rotating shaft 21 includes a moving block 22 also serving as a bearing member.
The moving block 22 is provided with a motor 23 for rotatingly driving the rotating shaft 21. The two moving blocks 22 and 22 move in directions approaching and separating from each other. For this purpose, the moving blocks 22 and 22 are guided by a slide guide 24 and a screw shaft 25 is driven by a motor 26. Accordingly, the roll brushes 20, 20 are displaced in a direction of approaching / separating from each other.

In the scrub cleaning section 2, the work W is rotatably supported by chuck members 27 provided at three places. A cleaning liquid supply shower 28 is provided at an upper position of the work W supported by the chuck member 27. Therefore, while the cleaning liquid is supplied from the cleaning liquid supply shower 28 while the work W is supported by the chuck member 27, the roll brushes 20,
20 and the roll brush 20 is
, The work W is cleaned by scrubbing the front and back surfaces of the work W with the roll brush 20. In addition, since the work W rotatably supported by the chuck member 27 is rotationally driven by the rotation of the roll brush 20, the entire surface of the work W is uniformly washed. In addition, in addition to the cleaning liquid supply shower 28,
The cleaning liquid is also supplied to the inside of the rotating shaft 21 so that the roll brush 2
The cleaning liquid may be supplied also from the inner surface side of the “0”.
In addition, instead of the roll brush 20, the cleaning can be performed using a circular or annular surface brush that slides on the surface of the work W.

Further, the rinsing section 3 is for rinsing out the cleaning liquid used in the scrub cleaning section 2. For this reason, in the rinsing section 3, the work W is mounted on the spindle 29 and the upper part of the spindle 29 is mounted. A pure water supply shower 30 is provided. Therefore, the work W is the spindle 2
The washing liquid is washed away by rotating the rinsing liquid supplied from the pure water supply shower 30 while being rotated at 9.

In the drying section 4, the rinse liquid adhering to the surface of the work W is removed, and the work W is dried.
The drying of the work W is for performing high-speed spin drying, and the drying unit 4 is provided with a spindle 31. Accordingly, the spindle 31 chucks the inner diameter of the work W and rotates the work W at a high speed. The action of the centrifugal force caused by the high-speed rotation causes the rinse liquid to be scattered from the outer peripheral edge of the work W to which the rinse liquid has adhered. Further, in order to prevent the rinse liquid scattered in this manner from rebounding and re-adhering to the work W,
A bounce prevention cover 32 is provided around the spindle 31.

Next, a surface inspection unit 6 attached to the cleaning unit 5
, A front surface inspection device 33 is mounted, and the work W is inspected on the front surface side, inverted, and back surface side by the index table 34 at every predetermined angle.

FIG. 3 shows a schematic configuration of the surface inspection device 33. As is clear from the figure, the surface inspection device 33 includes a detection optical system 40 and a signal processing unit 41. The detection optical system 40 irradiates the workpiece W with a laser beam at different incident angles, and the first and second laser emitting means 4, 43.
First and second regular reflection light receiving units 44 and 4 for receiving regular reflection light from the work W of the laser beam emitted from the laser beams 2 and 43.
5, a bright-field light receiving unit 47 that receives the diffracted light of the light reflected by the beam splitter 46 from the optical path to the first regular reflection light receiving unit 44, and receives the scattered light from the surface of the workpiece W at different positions. First and second dark field light receiving sections 4
8, 49.

The five light receiving sections 44, 45, 47 to 4
9, the first and second laser emitting means 42, 4
3, the light reflected by the work W is received and subjected to photoelectric conversion to generate a voltage signal (or a current signal).
Is taken into the signal processing unit 41 via the amplifier 50. Then, by performing processing based on a predetermined algorithm on the signals from the respective light receiving units captured by the signal processing unit 41 in this manner, it is possible to determine whether the surface of the work W has a defect or not, Can also be specified. Here, as the surface defect of the work W,
There are scratches on the surface, fine irregularities on the surface of the work W itself, large undulations and distortions, particle defects with minute foreign matter attached, stains, film-like fixed substances, etc. Some stain defects exist. According to the surface inspection device 33 including the detection optical system 40 and the signal processing section 41 having the above-described configuration, the types of these surface defects can be almost accurately determined.

Thus, in the detection optical system 40, when minute projections are present on the surface of the work W, such as particles, scattered light is generated when the corresponding portion is irradiated with laser light. This scattered light is transmitted to the first and second dark field light receiving units 4.
Light is received at 8,49. In addition, the amount of light received by the first and second dark field light receiving units 48 and 49 differs between the particles and the minute protrusions. In addition, when the surface of the work W has irregularities, that is, when the height position of the surface changes, the work W is displaced so that the optical axis of the reflected light fluctuates accordingly. Therefore, the bright field light receiving unit 47 and the first and second regular reflection light receiving units 42 and 4
The shift in the light receiving position in No. 3 reduces the amount of received light. Moreover, the greater the unevenness of the surface of the work W, the greater the amount of received light decreases. Further, since the diffraction direction of the reflected light is different between the concave portion and the convex portion, the work W
It is possible to specify whether the surface defect is a concave surface defect or a convex surface defect. Further, if stains such as stains are present, the first and second regular reflection light receiving sections 42 and 43
In addition to the change in the amount of light received by the bright-field light receiving section 47,
Partially, the scattered light received by the first and second dark field light receiving units 48 and 49 also occurs. Further, a bright-field light receiving section 47,
Depending on the degree of decrease in the amount of light received by the first and second regular reflection light receiving units 42 and 43, it can be determined whether the surface irregularities are steep or slow.

As described above, the scanning is performed so as to move the detection optical system 40 in the radial direction of the work W while rotating the work W. By patterning the scattering information and the unevenness information obtained by each light receiving unit constituting the detection optical system 40 during this time, it is determined whether or not a defect exists on the surface of the work W, and how many types of defects are present. Can be detected. In the detection optical system 40,
A minute section, that is, a cell having a small area in the radial direction and the circumferential direction with respect to the surface of the work W, is set, and data is acquired for each cell. Here, in order to perform the defect determination more accurately, it is desirable to improve the resolution by reducing the cell area as much as possible.

In the signal processing section 41, five light receiving sections 44,
The detection signals from the light receiving units 45 and 47 to 49 are taken in. If there is no substantial change in the signals received by these light receiving units, that is, the first and second regular reflection light receiving units 42 and 43 and the bright field light receiving unit 47 There is no change in the amount of received light, and the first and second
If there is no substantial signal output from the dark field light receiving units 48 and 49, it is determined that the workpiece W has no surface defect. On the other hand, when any one of the light receiving sections 44, 45, and 47 to 49 changes, which light receiving section has changed, and which of the light receiving sections has the largest signal change, the planar view of the light receiving section has changed. Based on the spread, the type of the defect is specified.

Here, the types of defects generated on the surface of the work W are limited to some extent. In general, particles, abrasions (scratch), minute recesses (pits),
Deformation resulting from stress caused by the action of external force, such as minute projections (bumps) and stains, is typical. Among them, the particle defect and the stain defect are defects that do not occur if the work W is completely cleaned. Therefore, in the signal processing unit 41, the particle defect and the stain defect among the types of the identified defects are taken into the controller 10 as data for monitoring the cleaning conditions, and the controller 10 evaluates the cleaning accuracy. The unloader unit 8 includes a classifying unit that classifies and sorts the work W based on the inspection result of the surface inspection unit 6. Divide it into good products. Then, the cleaning defective product is re-cleaned, and other defective products are discharged out of the system. In this way, the defective cleaning is distinguished from other defective products, and the defective cleaning is re-cleaned, thereby improving the processing efficiency and the yield.

When a large number of defective cleaning products are generated, the processing becomes complicated, which causes a decrease in throughput. Therefore,
When a particle defect and a stain defect are detected by the surface inspection unit 6, the data is taken into the controller 10 and it is determined whether or not there is a problem in the cleaning accuracy. As a result, when it is determined that the cleaning accuracy is reduced, , And is configured to output a command to change the cleaning conditions.

The defects generated based on the cleaning accuracy include:
As described above, there are a particle defect and a stain defect. However, the ultrasonic cleaning unit 1 can mainly preferably remove particles, and scrub cleaning is effective for removing stain. Furthermore, stains may also occur in the drying unit 4 that performs high-speed spin drying of the work W. For example, if the work W is dried once by performing high-speed spin drying and then the liquid adheres again, the part may be stained. Furthermore, although there is little causal relationship,
It cannot be said that there is no stain defect due to poor washing of the cleaning liquid in the rinsing section 3.

From the above, the conditions of the ultrasonic cleaning unit 1, the scrub cleaning unit 2, the rinsing unit 3 and the drying unit 4 can be changed. However, in the scrub cleaning unit 2, only the stain is removed. In addition, it also functions to remove particles. Further, in the scrub cleaning section 2, since the work W is directly scrubbed using the roll brush 20, the cleaning conditions change every moment due to wear or set of the roll brush 20. Therefore, it is necessary to change the cleaning conditions at least for the scrub cleaning unit 2. If the cleaning accuracy of the scrub cleaning unit 2 is maintained in an expected state, the degree of occurrence of defective cleaning is reduced. Will be significantly reduced.

The cleaning conditions determined by the scrub cleaning section 2 include a cleaning time and a cleaning time depending on the pressing force of the roll brush 20 against the work W, the rotation speed of the roll brush 20, the supply amount and the pressure of the cleaning liquid, and the like. Affects accuracy. Here, if you change the cleaning time to be longer,
It is not preferable to make this washing time variable since it affects other steps. The pressing force of the roll brush 20 against the work W and the number of rotations thereof are factors directly affecting the cleaning ability. Therefore, the cleaning conditions controlled by the controller 10 are at least the pressing force of the roll brush 20 against the work W and the number of rotations thereof.

By the way, if the cleaning, rinsing and drying steps take a sufficiently long time, the degree of occurrence of defective cleaning of the work W decreases accordingly. However, there is a time constraint from the viewpoint of improving the throughput and the like. Therefore, it is extremely difficult to perform complete cleaning, and even when the scrub cleaning unit 2 exhibits a desired cleaning accuracy. And a certain number of defective cleaning products are generated. For example,
When 100 wafers are washed, some defects occur in about several workpieces W. From the above, for example, it is set that about 5 workpieces W have defective cleaning products per 100 workpieces W, and more than 7 workpieces 1
When the number of defective cleaning products increases, such as zero, cleaning conditions are changed to improve cleaning efficiency.

In the controller 10, for example,
The processing shown in FIG. 4 is performed. First, the controller 10
Then, the detection result of the surface inspection unit 6 is fetched (step 1). Then, it is determined from the captured data whether or not the cleaning is defective, that is, whether or not there is a surface defect and the type of the defect is a particle defect or a stain defect (step 2). If the cleaning is defective, the defective counter is counted (step 3).
In addition, if it is a defective cleaning product, it is counted on a processing number counter irrespective of whether it is a non-defective product (step 4).

In the processing described above, it is determined whether or not the number of processed sheets has reached a predetermined set number (step 5).
The defective cleaning rate is calculated (step 6). Then, it is determined whether or not the defective cleaning rate exceeds a predetermined set value (step 7). If the defective cleaning rate is less than the set value, the defective counter and the number of processed sheets counter are reset. (Step 8), and the process returns to step 1.

If the defective cleaning rate is equal to or higher than the set value, it is determined whether or not the brush needs to be replaced (step 9). Then, the process returns to step 1 via step 8 (step 10). When it is determined that there is a need to replace the brush, a brush replacement request is issued by alarm means such as a buzzer (step 11).

Here, the cleaning conditions are changed by increasing the pressing force of the roll brush 20 against the work W and increasing the rotation speed of the roll brush 20.
The pressing force of the roll brush 20 is executed by reducing the distance between the moving blocks 22 and 22 by the screw shaft 25 when the roll brush 20 is brought into contact with the workpiece W. The rotation speed of the roll brush 20 is controlled by a motor 23.

The necessity of brush replacement is determined by comparing the cleaning defective rate in the previous cycle with the defective rate in the current cycle. Assuming that the previous defective cleaning rate is equal to or higher than the set value, the cleaning conditions have been changed, and the defective cleaning rate should normally decrease. Nevertheless, an increase in the defective cleaning rate indicates that the roll brush 20 is worn or sagged, and it is no longer possible to maintain proper cleaning accuracy. In other words, despite the fact that cleaning conditions have already been changed, the occurrence rate of defective cleaning products does not decrease,
Even if the cleaning conditions are further changed, it is determined that there is no room for improving the cleaning efficiency. Then, after issuing the brush replacement request, the operation of the apparatus can be stopped. However, the cleaning itself does not necessarily become impossible. Therefore, it is desirable to continue the operation of the apparatus for the time being.

As described above, the scrub cleaning process using the roll brush 20 is constantly monitored by the controller 10, and when the cleaning capability of the roll brush 20 is reduced, the cleaning conditions are changed to further enhance the cleaning capability. Thereby, high cleaning efficiency is always exhibited, and generation of defective cleaning can be suppressed. Further, when the cleaning ability cannot be maintained due to wear, settling, or the like of the roll brush 20, it can be accurately determined. as a result,
Roll brush 20 can be replaced at the optimal timing, and despite maintaining the desired cleaning ability,
The occurrence of a situation where the roll brush 20 is replaced can be prevented.

In the drying section 4, if the rotation speed and the time of the spindle 31 are insufficient, the rinsing liquid cannot be completely shaken off, and as a result, the remaining rinsing liquid flows on the dried surface, causing stains. That is, the frequency of occurrence of stain defects in the processing stage of the drying unit 4 is relatively high. In addition, if the rotation speed of the spindle 31 is increased, occurrence of stains can be suppressed. Therefore, the controller 10
The number of works W having a particle defect and the number of works W having a stain defect are separately calculated as detection results of the surface inspection unit 6 taken into the apparatus. It is also possible to control so as to change the drying conditions of the drying unit 4 such as the rotation speed of the rotation unit 31, the time until the stationary rotation state is reached, and the degree of deceleration at the time of stopping. In particular, if the number of stain defects among the defective cleaning products does not decrease even if the scrub cleaning conditions are changed, the drying condition in the drying unit 4 is changed. If the stain defects still do not decrease, a brush replacement request is issued. You can also set it to output.

[0037]

As described above, according to the present invention, when the surface of a work after cleaning is inspected and the number of defective products is large, the cleaning condition is changed to change the cleaning conditions. Thus, it is possible to suppress the elimination of the work caused by the above as much as possible and to improve the cleaning efficiency.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a basic configuration of a work cleaning apparatus.

FIG. 2 is an explanatory diagram of a configuration of a scrub cleaning unit.

FIG. 3 is an explanatory diagram of a configuration of a surface inspection mechanism.

FIG. 4 is a flowchart illustrating a procedure for changing cleaning conditions in a controller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic cleaning part 2 Scrub cleaning part 3 Rinse part 4 Drying part 5 Cleaning part 6 Surface inspection part 10 Controller 20 Roll brush 21 Rotary shaft 22 Moving block 23 Motor 25 Screw shaft 31 Spindle 33 Surface inspection device 40 Inspection optical system 41 Signal Processing unit W Work

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA49 BB01 BB03 CC03 CC19 FF41 FF44 FF48 GG04 HH04 HH14 JJ05 JJ15 QQ31 TT00 3B116 AA02 AA03 AB34 BA02 BA14 BB02 BB22 BB33 BB62 BB85 CC05 GA05 GA06

Claims (3)

[Claims] 1. A cleaning method for cleaning a surface of a plate-like work.
Alternatively, a cleaning mechanism including a plurality of cleaning processes and a drying process for drying the workpiece after cleaning, a surface inspection unit for performing a defect inspection of the surface of the workpiece after cleaning and drying, and a work based on a detection result of the surface inspection unit. A cleaning controller for changing cleaning conditions in the cleaning mechanism when the cleaning accuracy is determined and the cleaning accuracy is reduced. 2. The cleaning step of the cleaning mechanism includes a scrub cleaning step in which at least a brush is brought into contact with both front and back surfaces of a workpiece, and scrub cleaning is performed while rotating the brush. The apparatus according to claim 1, wherein the controlled cleaning condition is at least one of a pressing force of the brush against the work and a rotation speed thereof. 3. The surface defect item detected by the surface inspection unit includes at least the presence or absence of an attached foreign matter and a fixed foreign matter on the surface, and the controller determines that the work having the attached foreign matter and the fixed foreign matter is a predetermined number. The apparatus for cleaning a plate-like workpiece according to claim 1, wherein when only the above is detected, the cleaning accuracy is determined to be reduced.