JP2007027784A - Versatile cleaner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary versatile cleaner, where the problem of dust occurrence from a rotary sliding part is eliminated, and cleaning and drying can be carried out while shutting off the outer air perfectly. <P>SOLUTION: A member for holding a matter to be treated is disposed, while being coupled with a rotary shaft, in a cleaning bath having parts for feeding and discharging cleaning liquid. The matter is cleaned and/or dried while turning. The rotary shaft penetrates the discharging part. The cleaner further comprises means for controlling the flow rate of cleaning liquid discharged through the discharging part, and means for shutting off the cleaning bath from the outer air by means of the cleaning liquid itself being discharged through the discharging part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotary universal cleaning device, and more particularly to a cleaning device that prevents dust from entering a cleaning tank from a sliding portion.

  In recent years, with further higher integration of semiconductor integrated circuits, circuit patterns formed on the surface of semiconductor wafers have become finer and more complicated. For this reason, even if a fine foreign matter or a small amount of impurities adheres to the semiconductor wafer, the characteristics of the semiconductor circuit deteriorate and the manufacturing yield decreases. Therefore, the cleaning process is extremely important in the semiconductor manufacturing process.

  As a method for cleaning a semiconductor wafer, a cleaning method is used in which a cleaning liquid or an inert gas is jetted to clean and dry while rotating a semiconductor substrate in a cleaning tank. In the rotary cleaning apparatus for this purpose, the rotating shaft of the substrate holding member passes through the apparatus and is supported by a bearing. Since this bearing is exposed to the inside of the cleaning tank, dust generated by sliding is generated in the cleaning tank. There is a problem of polluting the atmosphere. In addition, there is a problem that outside air is mixed from the penetrating portion and the like, and the inside of the cleaning tank and thus the object to be cleaned is contaminated.

  In view of such circumstances, an object of the present invention is to provide a rotary universal cleaning device that eliminates the problem of dust generation from the rotating sliding portion. Furthermore, it aims at providing the washing | cleaning apparatus which can perform washing | cleaning and a drying process in the state interrupted | blocked with external air.

The present invention provides a cleaning device in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying is performed while rotating the cleaning target. A device,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
An all-purpose cleaning apparatus comprising a flow rate control means for adjusting a discharge flow rate of the cleaning liquid discharged from the gap.

The present invention provides a cleaning device in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying is performed while rotating the cleaning target. A device,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
A universal cleaning apparatus, wherein a container for rotating with the rotating shaft and receiving the cleaning liquid discharged from the gap is disposed on the rotating shaft below the gap.

The present invention provides a cleaning device in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying is performed while rotating the cleaning target. A device,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
A universal cleaning apparatus having a cylindrical body having an upper surface and a center welded to a rotating shaft, and a liquid reservoir, below the gap.

  A liquid level holding drain pipe is provided.

  A flow rate control means for adjusting the discharge flow rate of the cleaning liquid discharged from the gap is provided.

  The inside of the cleaning tank is blocked from outside air by the cleaning liquid itself discharged from the gap.

The flow rate control means includes the rotation shaft having at least two different outer diameters, and a displacement means for displacing an axial relative position of the discharge pipe and the rotation shaft.
The discharge part has a taper that decreases as the opening diameter goes downward, and the rotation shaft has a large diameter part having a taper part having the same angle as the taper of the discharge pipe.

The flow rate control means is characterized in that irregularities, fins, or grooves are provided on the rotating shaft or the discharge portion, and the outflow amount is adjusted by the rotating direction and / or rotating speed of the rotating shaft.
At least a part of the rotating shaft is made hollow so that the cleaning liquid stored in the container is discharged from the lower portion through the rotating shaft.

  The discharge flow rate of the cleaning liquid is controlled to be 1 to 10% of the supply amount of the cleaning liquid.

It is possible to avoid the problem of dust generation from the rotating sliding part.
The effect of preventing the entry of dust and impurities from the outside during the cleaning process is further improved, so that higher integration and higher performance of the integrated circuit can be achieved, and the manufacturing yield can be improved.

  Management of the discharged cleaning liquid becomes easy, and downsizing of the apparatus can be achieved.

  During the cleaning process, the surface of the object to be cleaned can be kept clean without being affected by outside air. As a result, higher performance of the integrated circuit can be achieved.

  It is possible to process a large number of substrates at a time, and it is possible to reduce production costs such as production efficiency and reduction of the amount of cleaning liquid used.

  The present invention is not limited to semiconductor substrates and photomasks, and can be applied to all types of precision cleaning. For example, the present invention can also be suitably applied to cleaning of metals that are oxidized when they come into contact with the atmosphere.

  An example of the semiconductor wafer cleaning and drying apparatus of the present invention is shown in FIGS. 1 and 2, and the present invention will be described using this.

  FIG. 1 is a conceptual diagram showing the basic concept of the cleaning apparatus of the present invention.

  In FIG. 1, 101 is a cleaning tank, 102 is a lid, 103 is a cleaning liquid supply pipe, and 104 is a rotation holding member for the semiconductor substrate 105. Reference numeral 106 denotes a discharge portion, and in the example shown in the figure, a pipe having a taper that is disposed at the center of the bottom surface of the cleaning tank 101 and whose opening diameter decreases as it goes downward is used. A rotating shaft 107 passes through the discharge portion 106, one of which is connected to a holding member 104 and the other is connected to a driving motor 109. The rotating shaft 107 has a large-diameter portion 110 having a tapered portion having the same angle as the taper of the discharge portion, and a cleaning liquid receiving container 108 that rotates together with the rotating shaft.

  As shown in FIG. 1, in the cleaning device of the present invention, since the bearing supporting the rotating shaft is excluded from the cleaning tank, there is a problem of dust generation at the sliding portion between the rotating shaft and the bearing, which is a problem in the conventional device. Can be avoided. In addition, the cleaning liquid flowing between the rotating shaft and the discharge portion can prevent dust from entering from the outside.

  For example, as shown in FIG. 3, the liquid accumulated in the receiving container 108 may have a structure in which a discharge pipe 302 is attached to the receiving container 108 and the discharged liquid is discharged into an annular discharged liquid receiving groove 303. In this case, it is preferable to provide a plurality of discharge pipes 302 in consideration of the balance during rotation. Alternatively, it may be annular like the receiving groove 303.

  Further, the liquid stored in the receiving container 108 may be further provided with a container 402 for receiving the cleaning liquid overflowing the receiving container 108 as described in FIG.

  Further, as shown in FIG. 6, the inside of the rotating shaft 107 is made hollow at the lower portion from the receiving container 108, and the cleaning liquid accumulated in the container 108 passes through the discharge port 601 and the hollow portion 602 from the lower portion of the rotating shaft 107. It is good also as a structure which discharges. Further, for example, by providing a valve 603 at the lower end of the rotating shaft 107, the discharge amount can be adjusted.

  FIG. 2 is a conceptual diagram showing a preferred example of the cleaning apparatus of the present invention.

  In FIG. 2, 201 is a cleaning tank, 202 is a lid, 203 is a plurality of cleaning liquid supply pipes, and 204 is an inert gas supply pipe. Reference numeral 205 denotes a megasonic ultrasonic vibrator, 206 an infrared lamp for heating the semiconductor substrate, and 207 a rotation holding member for the semiconductor substrate 208. In addition, a semiconductor substrate transfer device (not shown) is connected to the cleaning tank 201 so that the semiconductor substrate can be carried out and loaded without being exposed to the atmosphere.

  Reference numeral 209 denotes a cleaning liquid discharge portion, and 210 denotes a rotating shaft having a large-diameter portion 211 having the same structure as that shown in FIG. The rotating shaft 210 is connected to a rotation holding member 207 and a driving motor 217 and is supported by a bearing 220.

  212 is an outside air blocking means for blocking the inside of the discharge unit 209 and the cleaning tank 201 from the outside air, and has a cylindrical body 213 having a top surface welded to the rotary shaft 210, a liquid reservoir 215, and a liquid level holding drainage liquid. The pipe 216 is configured. Reference numerals 214 and 219 denote drain valves and pipes for discharging the cleaning liquid in the liquid reservoir 215 when the cleaning liquid is replaced. The cleaning device of FIG. 2 has a configuration in which a bearing 220 is provided, but dust generated in the bearing 220 is blocked by the cleaning liquid itself stored in the liquid reservoir 215, and mixing into the cleaning tank 201 is completely prevented. The

Reference numeral 218 denotes a displacement means for displacing the relative positions of the discharge pipe 209 and the rotation shaft in the axial direction, and 221 denotes a motor support member, which are housed in the housing 222. In order to prevent the cleaning liquid from being contaminated by vapor or mist, the housing 222 is configured to flow dry N ₂ gas, clean air, inert gas, or the like.

  A method for cleaning a semiconductor substrate including a hydrofluoric acid, ultrapure water rinse, isopropyl alcohol (IPA) cleaning, and a drying process will be described using the apparatus shown in FIG.

(A) Hydrofluoric acid cleaning First, the silicon wafer 208 is set on the holding member 207 by a transfer device (not shown).

  When the hydrofluoric acid is poured into the cleaning tank 201 from the first cleaning liquid supply pipe 203 and the silicon wafer is sufficiently covered, the holding member 207 is rotated at a low speed to a medium speed (for example, 30 to 500 rpm), and the ultrasonic vibrator The wafer is cleaned by applying a voltage to 205 and irradiating the wafer with 1 to 5 MHz megasonic ultrasonic waves. By applying a megasonic ultrasonic wave, the cleaning effect is further improved, and in particular, dust, impurities, etc. in a trench such as a trench can be completely removed.

  The hydrofluoric acid flows downward through the gap between the large-diameter portion 211 of the rotating shaft 210 and the discharge portion 209, and is discharged from the liquid reservoir 215 through the liquid level holding pipe 216 to a drain tank (not shown). Accordingly, the inside of the cleaning tank 201 is completely shielded from dust generated in the bearings and the like by the gap between the large diameter portion 211 and the discharge portion 209 of the rotating shaft 210 and the cleaning liquid itself stored in the liquid reservoir 215. Become.

  In the above cleaning, impurities and dust adhering to the silicon wafer are removed from the wafer surface very effectively by the rotational movement of the wafer, the supply of fresh cleaning liquid, and the action of megasonic ultrasonic waves. It is discharged to the outside through.

  The flow rate at which the liquid is discharged through the gap is determined by the size of the gap between the large-diameter portion 211 of the rotating shaft 210 and the discharge pipe 209. The flow rate is 1 to 10% of the supply amount. preferable. Usually, this gap is set to 1 to 10 mm, but is appropriately determined according to the viscosity of the liquid.

After the hydrofluoric acid cleaning is completed, N ₂ gas is supplied into the tank, and the rotating shaft 210 is moved upward by the displacement means 218 to increase the gap between the discharge portion 209 and the large-diameter portion 211 of the rotating shaft. The acid is dropped and released to the outside. Even in this case, since hydrofluoric acid is accumulated in the liquid reservoir 215, dust or the like does not enter the cleaning tank 201 and the discharge pipe 209.

(B) Ultrapure water rinse cleaning Subsequently, ultrapure water is supplied from the ultrapure water supply pipe into the tank, and ultrapure water rinse cleaning is performed in the same manner as the hydrofluoric acid cleaning.

(C) IPA cleaning and dry IPA is supplied into the tank from the IPA supply pipe, and cleaning is performed in the same manner as the hydrofluoric acid cleaning. Thereafter, the wafer 208 is heated at a high speed (1000 to 3600 rpm) while heating the wafer 208 with the infrared lamp 206 while supplying N ₂ gas, and the IPA adhering to the wafer is removed and dried. Also in this process, since the entry of dust from the outside is prevented, the wafer is always kept in a clean atmosphere. Therefore, a highly clean wafer surface can be maintained, and a high production yield can be stably obtained.

  In addition, when discharging an inorganic drainage such as hydrofluoric acid and an organic drainage such as IPA into separate drainage tanks, the inorganic system connected to the drainage pipe 216 is washed after the ultrapure water rinse. The drainage tank may be switched to an organic drainage tank. Further, in order to completely separate the cleaning liquids, the cleaning liquid collected in the liquid reservoir 215 may be discharged from the drain pipe 219.

  Depending on the cleaning liquid, the cleaning liquid may be returned from the drain pipe 216 and the drain pipe 219 to the supply pipe via a filter or the like.

(Example embodiment)
The above describes the example in which the hydrofluoric acid cleaning, ultrapure water rinsing, and IPA cleaning / drying steps are continuously performed with the apparatus of FIG. 2. However, the cleaning apparatus of the present invention is not limited to these cases, A process using a cleaning liquid can also be added. Alternatively, for example, one apparatus is provided for each process, such as a hydrofluoric acid cleaning / ultra pure water rinsing apparatus and an IPA cleaning / drying apparatus, and a method of transporting a substrate between these apparatuses is adopted. Also good.

  In the cleaning apparatus of the present invention, for example, an O-ring or the like is incorporated in a portion having an angle of the rotation shaft or the discharge portion in FIG. 2 so that the drainage does not flow completely by pressing the rotation shaft against the O-ring. It can also be used as a general cleaning tank.

  Further, the cleaning apparatus of the present invention is not limited to the method of cleaning by immersing the substrate in the cleaning liquid, but can also be applied in the same manner when cleaning is performed by spraying the cleaning liquid onto the substrate surface such as a spray. In this case as well, the cleaning liquid in the gap between the rotating shaft and the discharge section and / or the cleaning liquid itself stored in the liquid pool can similarly prevent the intrusion of dust from the sliding section, and can block the cleaning tank from the outside air. Therefore, cleaning in a highly clean atmosphere is possible.

  Furthermore, in the present invention, when the substrate is not immersed in the cleaning liquid, the cleaning can be effectively performed by spraying the jet surface of the cleaning liquid containing megasonic ultrasonic waves on the substrate surface. Further, the cleaning effect can be further enhanced by arranging an ultraviolet lamp in the cleaning tank and irradiating the substrate surface with ultraviolet rays to radically activate the cleaning liquid.

  In the following, the main components of the present invention will be described in more detail.

<Flow control means>
The flow rate control means shown in FIG. 2 comprises a rotary shaft having a large diameter portion whose outer diameter changes with a predetermined angle, and a displacement means for displacing it in the axial direction. The rotation shaft is not limited as long as it has at least two different outer diameters, and the discharge portion is not tapered and may be a straight pipe. However, by changing the outer diameter of the rotating shaft in multiple stages, and further by changing it continuously, it can be applied to various cleaning liquids having a wide range of viscosities, increasing the degree of freedom in selecting the cleaning liquid, Controllability is also improved.

  Further, the displacing means may move the cleaning tank and the discharge unit instead of moving the rotating shaft itself. As the displacement means for moving the rotating shaft or the washing tank, these may be mechanically moved, or a permanent magnet is arranged on a part of the rotating shaft, and an electric current is passed through a coil disposed around the rotating magnet. It may be moved by the interaction of magnetic fields.

  In addition to the above, the flow rate control means of the present invention may be anything as long as the flow rate can be adjusted. For example, a member that can change the inner diameter continuously or stepwise as the aperture of the camera is used. This may be provided in the discharge portion or the bottom opening of the cleaning tank.

  As one aspect of the preferred flow rate control means, as shown in FIG. 3, there is one in which a spiral fin 301 is disposed on the rotating shaft 107. Thereby, the amount of drainage can be controlled by changing the rotation speed of the rotating shaft, and the drainage can be forcibly discharged by rotating in the reverse direction. In the example of FIG. 3, an example in which a spiral fin is provided is shown, but the present invention is not limited thereto, and irregularities, grooves, or the like may be provided on the rotation shaft or the discharge portion, and the flow rate can be adjusted by the rotation speed or the rotation direction. If it is a thing, it is not necessary to limit to a spiral shape in particular.

  Further, if the method of FIG. 3 is used, the above displacement means and the like are unnecessary, but it goes without saying that they may be used together. In FIG. 3, the liquid accumulated in the receiving container 108 is discharged through the discharge pipe 302 into the annular drain receiving groove 303 as described above, but the structure shown in FIGS. It goes without saying that it is good.

<Outside air blocking means>
The structure shown in FIG. 2 can block the inside of the washing tank from the outside air around the bearing, but in addition to this, for example, as shown in FIG. 4, the cylindrical body 213 of FIG. The inner diameter of the cylindrical body 401 may be larger than the outer diameter of the discharge portion (discharge pipe) 209, and the cylindrical body may overlap the discharge pipe 209 in the axial direction. In this configuration, the cleaning tank 201 can always be shut off from the outside air by the cleaning liquid accumulated in the cylindrical body 401.

  The cleaning liquid overflowing from the cylindrical body 401 is received by a container 402 fixed to a cleaning tank or the like and discharged to the outside through a pipe 403. In this case, in order to prevent the cleaning liquid from flowing along the bottom surface of the cylindrical body 401 to the bearing 220 side, it is preferable to further provide a second cylindrical body 404 on the bottom surface.

  Further, as shown in FIG. 6, the cleaning shaft stored in the cylindrical body 401 is not overflowed, and the inside of the rotating shaft is made hollow, and the cleaning liquid stored in the cylindrical body is discharged from the lower portion of the rotating shaft through the hollow portion. In this case, a valve may be provided at the lower part of the rotary shaft so that the discharge flow rate can be adjusted.

<Washing tank>
In the present invention, it is preferable to provide a partition plate whose lower end is fixed to the bottom surface of the cleaning tank so as to surround the holding member 207 in the cleaning tank 201. By providing a partition plate and overflowing a part of the supplied cleaning liquid and taking it out of the cleaning tank, relatively heavy garbage is externally removed together with the cleaning liquid flowing downward through the gap between the discharge unit 209 and the rotating shaft 211 described above. The light waste can be discharged to the outside together with the cleaning liquid overflowing the partition plate, and the dust removal effect is further improved. Further, the cleaning liquid overflowing from the partition plate can pass through the filter and then returned to the cleaning liquid supply pipe to reduce the amount of the cleaning liquid used.

  Moreover, it is preferable to incline the bottom face of the washing tank downward toward the discharge part opening. Thereby, garbage etc. flow into the discharge part opening quickly, and the discharge becomes more efficient.

<Holding member>
Although the single wafer cleaning / drying apparatus has been described with reference to FIG. 2, the universal cleaning apparatus of the present invention can also wash a large number of sheets at once. An example is shown in FIG. FIG. 5A is a schematic plan view and FIG. 5B is a schematic cross-sectional view of a holding member in which six wafer cassettes are arranged.

  The holding member includes a disk 502 fixed to the rotation shaft 501 and a holding portion 503 of a wafer cassette 505 that stores a wafer 504.

  As shown in FIG. 4, a wafer storage cassette 505 is fitted and attached to a holding portion 503, and the cleaning liquid is supplied and rotated and cleaned in the same manner as in the single wafer type. Since the wafer surface is horizontally arranged, a high cleaning effect can be obtained by the centrifugal force of rotation.

  As in the case of the single wafer type, the cassette is preferably loaded and unloaded by the transport mechanism and attached to and detached from the holding portion.

<Heating means>
As a heating means, in addition to heating the substrate with an infrared lamp or the like, the holding member may be directly heated by providing an electric heater or the like, or a heated inert gas or the like may be sprayed onto the substrate.

<Materials and others>
As a material of a member in contact with the cleaning liquid, such as the rotating shaft, the inner wall of the tank, or the holding member, a material that is not affected by the cleaning liquid and does not generate impurities or the like is used. For example, quartz, stainless steel or the like coated with silicon rubber or polyethylene and further coated with Teflon (registered trademark) is preferably used. By using these, it is also possible to perform cleaning using a highly corrosive cleaning liquid such as hydrofluoric acid, H ₂ SO ₄ —H ₂ O ₂ , NH ₄ OH—H ₂ O ₂ .

  The rotation shaft may be directly fixed to a rotation drive source such as a motor and rotated, or may be rotated via a gear / belt.

It is a conceptual diagram explaining the concept of the washing | cleaning apparatus of this invention. It is a conceptual diagram which shows an example of the washing | cleaning apparatus of this invention. It is a conceptual diagram which shows the other example of the washing | cleaning apparatus of this invention. It is a conceptual diagram which shows the other example of the external air interruption | blocking means of this invention. It is a conceptual diagram which shows an example of the holding member of this invention. It is a conceptual diagram which shows the other example of the washing | cleaning apparatus of this invention.

Explanation of symbols

101 washing tank,
102 lid,
103 cleaning liquid supply pipe,
104 rotation holding member,
105 semiconductor substrate,
106 discharge part (discharge pipe),
107 axis of rotation,
108 Drainage receptacle,
109 motor,
110 Large diameter part of the rotating shaft,
201 washing tank,
202 lid,
203 a plurality of cleaning liquid supply pipes,
204 inert gas supply pipe,
205 megasonic ultrasonic transducer,
206 Infrared lamp for heating a semiconductor substrate,
207 rotation holding member,
208 semiconductor substrate,
209 discharge section,
210 rotation axis,
211 large diameter part,
212 Outside air blocking means,
213 cylinder,
214 drain valve,
215 liquid reservoir,
216 Liquid level holding piping,
217 motor,
218 displacement means,
219 drain piping,
220 bearings,
221 motor support,
222 housing,
301 spiral fins,
302 discharge pipe,
303 annular drainage groove,
401 cylinder,
402 containers,
403 piping,
404 Spill-off prevention cylinder,
501 rotation axis,
502 discs,
503 cassette holder,
504 wafers,
505 Wafer cassette 601 outlet,
602 hollow part,
603 Valve.

Claims (11)

A cleaning apparatus in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying while rotating the cleaning target. ,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
An all-purpose cleaning apparatus comprising a flow rate control means for adjusting the discharge flow rate of the cleaning liquid discharged from the gap. A cleaning apparatus in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying while rotating the cleaning target. ,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
A universal cleaning apparatus, wherein a container for rotating with the rotating shaft and receiving the cleaning liquid discharged from the gap is disposed on the rotating shaft below the gap. A cleaning apparatus in which a cleaning member holding member is connected to a rotating shaft inside a cleaning tank having a cleaning liquid supply unit and a discharge unit, and cleaning and / or drying while rotating the cleaning target. ,
The rotating shaft is disposed with a gap between the rotating shaft and the cleaning tank and penetrating the discharge portion,
A universal cleaning apparatus comprising a cylindrical body having an upper surface and a center welded to a rotating shaft, and a liquid reservoir, below the gap. 4. The universal cleaning apparatus according to claim 3, further comprising a liquid level holding drain pipe. The universal cleaning apparatus according to any one of claims 2 to 4, further comprising a flow rate control means for adjusting a discharge flow rate of the cleaning liquid discharged from the gap. The universal cleaning apparatus according to any one of claims 1 to 5, wherein the inside of the cleaning tank is blocked from outside air by the cleaning liquid itself discharged from the gap. The flow rate control means comprises the rotation shaft having at least two different outer diameters, and a displacement means for displacing an axial relative position of the discharge portion and the rotation shaft. 5. A universal cleaning apparatus according to 5. 8. The discharge part according to claim 1, wherein the discharge part has a taper that decreases as the opening diameter goes downward, and the rotary shaft has a large diameter part having a taper part having the same angle as the taper of the discharge pipe. An all-purpose cleaning device according to any one of the above. The flow rate control means is provided with irregularities, fins, or grooves on the rotating shaft or the discharge portion, and adjusts the outflow amount according to the rotating direction and / or rotating speed of the rotating shaft. The universal cleaning apparatus according to any one of 5 and 6. The universal cleaning apparatus according to claim 2, wherein at least a part of the rotating shaft is hollow so that the cleaning liquid stored in the container is discharged from the lower portion through the rotating shaft. The universal cleaning apparatus according to any one of claims 1 to 10, wherein a discharge flow rate of the cleaning liquid is controlled to be 1 to 10% of a supply amount of the cleaning liquid.

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