KR20220164428A - Cleaning apparatus - Google Patents

Abstract

The purpose of the present invention is to increase the efficiency of supplying cleaning water to an object to be cleaned by reducing an installation space of a pure water generating device, facilitating water quality management of the cleaning water, and simplifying a mechanism for supplying the cleaning water to the object to be cleaned. A cleaning device of the present invention, which cleans an object to be cleaned by using cleaning water, recovers waste liquid, regenerates and circulates the pure water, comprises: a holding table holding an object to be cleaned; a cleaning water supply nozzle supplying the cleaning water to the object to be cleaned held on the holding table; a waste liquid tank accommodating the used cleaning water as waste liquid; a waste liquid pump pumping the waste liquid from the waste liquid tank; a filter filtering the waste liquid pumped by the waste liquid pump and purifying the same into fresh water; a fresh water tank accommodating the fresh water; an ultraviolet light source irradiating ultraviolet rays to the fresh water; a fresh water pump pumping the fresh water from the fresh water tank; an ion exchange resin unit purifying the pure water by contacting the fresh water pumped by the fresh water pump with an ion exchange resin; and a resistivity meter measuring the resistivity of the pure water.

Description

Cleaning apparatus {CLEANING APPARATUS}

The present invention relates to a cleaning device that cleans a workpiece such as a wafer formed of a semiconductor material after being processed in the processing device.

In a manufacturing process of a device chip to be mounted on an electronic device, first, a plurality of division lines (streets) are set to intersect each other on the surface of a wafer formed of a semiconductor material. Then, a device such as IC (Integrated Circuit) and LSI (Large Scale Integration) is formed in each region partitioned by the division line. Thereafter, by dividing the wafer along the division line, a plurality of device chips can be obtained. For dividing the wafer, a cutting device or the like that cuts the wafer with an annular cutting blade is used.

In addition, in recent years, along with miniaturization and thinning of electronic devices, device chips are also required to be thinned. Therefore, in some cases, a process of thinning the wafer is performed by grinding the back side of the wafer before dividing the wafer. For the grinding process of the wafer, a grinding device or the like that grinds the wafer with a grinding wheel having a plurality of grinding stones is used.

After processing a workpiece such as a wafer using a processing device such as a cutting device or a grinding device described above, the workpiece must be cleaned to remove processing debris generated by the processing. Therefore, the processing device includes a cleaning device that cleans the workpiece by spraying cleaning water (see Patent Document 1 and Patent Document 2). The processed workpiece is washed with a cleaning device.

In the washing device, pure water is sprayed as washing water to an object to be cleaned, such as a workpiece. Then, the waste liquid including processing scraps and the like adhering to the object to be cleaned is discharged from the cleaning device and disposed of. However, the amount of pure water used in the cleaning device is large, and a non-negligible cost is required to dispose of the discharged waste liquid. Therefore, there is known a pure water generating device (waste liquid treatment device) that purifies and regenerates waste liquid and generates pure water usable as washing water again (see Patent Document 3).

Japanese Unexamined Patent Publication No. 2014-180739 Japanese Unexamined Patent Publication No. 2020-136300 Japanese Unexamined Patent Publication No. 2009-190128

Conventionally, when a deionized water generating device is installed adjacent to a cleaning device, an installation space for the demineralized water generating device has to be secured in addition to the installation space for the cleaning device in the vicinity of the processing device. This is because, if the pure water generating device is installed at a location away from the cleaning device, it becomes difficult to manage the quality of the pure water produced in the pure water producing device and transferred to the cleaning device.

Further, the pure water generating device needs to include a pump mechanism for sending pure water to the cleaning device regardless of the distance from the cleaning device. Further, the cleaning device needs to include a pump mechanism for supplying cleaning water such as pure water to objects to be cleaned, such as workpieces. In this way, it is necessary to operate a plurality of pump mechanisms in order to supply pure water regenerated from the waste liquid as washing water to the object to be cleaned, which sometimes becomes a factor in reducing the cleaning efficiency of the object to be cleaned.

The present invention has been made in view of these problems, and its object is to reduce the installation space of the pure water generating device, facilitate the quality management of washing water, and simplify the supply mechanism of washing water to the object to be washed. It is to provide a cleaning device capable of increasing the supply efficiency of cleaning water.

According to one aspect of the present invention, there is provided a washing apparatus for cleaning an object to be cleaned using washing water, recovering waste liquid, and regenerating and circulating pure water, comprising: a holding table for holding an object to be cleaned; A washing water supply nozzle for supplying washing water to the object to be washed, a waste tank for accommodating the washing water used for washing the object as waste liquid, a waste liquid pump for pumping the waste liquid from the waste liquid tank, and the waste liquid pump A filter for filtering the pumped waste liquid and purifying it into fresh water, a fresh water tank for accommodating the fresh water, an ultraviolet light source for irradiating ultraviolet rays to the fresh water, and a fresh water pump for pumping the fresh water from the fresh water tank , An ion exchange resin unit for purifying pure water by bringing the fresh water pumped up by the fresh water pump into contact with an ion exchange resin, and a resistivity value meter for measuring a resistivity value of the pure water.

Preferably, the maintenance table, the washing water supply nozzle, the waste medicine tank, the waste liquid pump, the filter, the fresh water tank, the ultraviolet light source, the fresh water pump, and the ion exchange resin It has a unit and a housing accommodating the resistivity value meter.

In addition, preferably, a precision filter for filtering pure water purified by the ion exchange resin unit and before the specific resistance value is measured by the specific resistance meter is further provided.

Further, preferably, it is connected to a first flow path leading to the waste tank and a second flow path passing to the washing water supply nozzle, and based on the specific resistance value of the pure water, the outflow destination of the pure water is set to the first flow path and the second flow path. , A switching valve for switching to one of the second flow passages is further provided.

Also, preferably, the fresh water pump functions as a supply driving source for supplying the pure water to the washing water supply nozzle when the switching valve makes the outflow destination of the pure water to the second flow path.

A washing device according to one aspect of the present invention includes a holding table and a washing water supply nozzle, and can wash an object to be cleaned with washing water. In addition, a waste liquid tank, a waste liquid pump, a filter, a fresh water tank, an ultraviolet lamp, a fresh water pump, and an ion exchange resin unit are provided, and used washing water can be purified to purify pure water. In addition, pure water having a resistivity meter and having been confirmed to satisfy a predetermined level of water quality is supplied from the washing water supply unit to the object to be cleaned.

A washing device according to one aspect of the present invention can wash an object to be cleaned and can also regenerate washing water. Therefore, there is no need to separately prepare the pure water generating device, and the space for installing the pure water generating device can be reduced. In addition, since the flow path of the purified pure water becomes very short, it is easy to manage the quality of the pure water supplied to the object to be cleaned. Further, since the cleaning device can supply pure water purified by the ion exchange resin unit as it is from the washing water supply unit to the object to be cleaned, the supply driving source for supplying the washing water to the object to be cleaned can be simplified.

Therefore, according to the present invention, a washing device capable of increasing the supply efficiency of the washing water by reducing the installation space of the deionized water generating device, facilitating the quality management of the washing water, and simplifying the supply mechanism of the washing water to the object to be cleaned is provided. Provided.

1 is a perspective view schematically showing a cleaning device.
Fig. 2 is a perspective view schematically showing a holding table and a washing water supply unit.
3 is a structural diagram schematically showing the configuration of a purification unit inside the cleaning device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments according to an aspect of the present invention will be described with reference to the accompanying drawings. First, the object to be cleaned by the cleaning device according to the present embodiment will be described. In the cleaning device, a workpiece processed by a processing device such as a cutting device or a grinding device is washed as the object to be cleaned.

BACKGROUND OF THE INVENTION In a processing device, for example, a workpiece such as a wafer formed of a semiconductor material such as Si (silicon) or SiC (silicon carbide) is processed. Devices such as a plurality of ICs and LSIs are formed on the surface of the wafer. By dividing the wafer for each device, individual device chips are formed. In addition, if the wafer is thinned by grinding the back side of the wafer in advance before dividing the wafer, thin device chips can finally be obtained.

A workpiece to be processed by the processing device may be previously integrated with a ring frame made of metal or the like and an adhesive tape applied to an opening of the ring frame. That is, the workpiece becomes a part of the frame unit by sticking to the adhesive surface of the adhesive tape exposed in the opening of the ring frame. Formation of the frame unit facilitates handling of the workpiece. Further, when the workpiece is divided into individual chips, handling of each chip becomes easy because each chip is continuously supported by the adhesive tape.

When a workpiece is processed with a processing device, processing debris is generated. In the processing apparatus, the workpiece is processed while processing water such as pure water is supplied, and the generated processing waste is washed away with the processing water. However, if the processing water containing the processing waste remains on the workpiece and the surface of the workpiece is dried, the processing waste adheres to the surface of the workpiece. Therefore, cleaning must be started promptly before the surface of the workpiece after machining dries.

Due to such circumstances, a cleaning device that uses a processed workpiece as an object to be cleaned is installed in the vicinity of the processing device. Alternatively, the cleaning device is incorporated inside the processing device. Next, the cleaning device according to the present embodiment will be described taking a cleaning device installed near a processing device as an example.

1 is a perspective view schematically showing a cleaning device 2 . The cleaning device 2 has a rectangular parallelepiped housing 4 accommodating the respective components, and a transparent opening/closing cover 6 and the like closing the upper portion of the interior space of the housing 4 on its outer surface.

The housing 4 is supported by four support legs 14, and the inclination of the housing 4 can be corrected by adjusting the length of each support leg 14. At the top of the housing 4, a cleaning space 16 (see FIG. 2) in which objects to be cleaned are cleaned is provided inside the opening/closing cover 6. When the opening/closing cover 6 is opened, objects to be cleaned can be carried in/out from the washing space 16 .

The cleaning device 2 has a control unit 8 inside the housing 4 that controls each component and operates each component so that the object to be cleaned can be washed under a predetermined cleaning condition. The control unit 8 includes, for example, a processing device such as a processor represented by a CPU (Central Processing Unit), and a main memory such as DRAM (Dynamic Random Access Memory), SRAM (Static Random Access Memory), ROM (Read Only Memory) It is composed of a computer including a device and an auxiliary storage device such as a flash memory, a hard disk drive, and a solid state drive.

The auxiliary storage device stores software including a predetermined program. By operating the processing device according to this software, the functions of the control unit 8 can be realized. Then, by operating the processing device according to software such as a program stored in the auxiliary storage device, the software and the processing device (hardware resource) function as a cooperative concrete means.

The washing device 2 further includes a display unit displaying various kinds of information and a display 10 with a touch panel that also functions as an input interface used for inputting various commands. In addition, the cleaning device 2 is equipped with an alarm lamp 12 indicating the state of the cleaning device 2, such as operating conditions or errors. In addition, an emergency stop button 18 for forcibly ending the operation of the cleaning device 2 is installed on the outer surface of the cleaning device 2 .

Next, components contributing to the cleaning of the object to be cleaned in the cleaning device 2 will be described. FIG. 2 is a perspective view schematically showing the cleaning space 16 inside the cleaning device 2. As shown in FIG. The washing space 16 is a space surrounded by the rectangular water case 16a, and the washing unit 20 is installed in the washing space 16. The water case 16a is connected with a duct (not shown) serving as intake and exhaust. The cleaning unit 20 includes a spinner table mechanism 22, a washing water receiving mechanism 24 surrounding the spinner table mechanism 22, and a cleaning mechanism 26 that cleans an object to be cleaned. .

The spinner table mechanism 22 has a holding table (spinner table) 28 and a motor (not shown) that rotates the holding table 28 about an axis along a direction perpendicular to the upper surface. Above the holding table 28, a porous member 28a exposed upward is disposed. Inside the holding table 28, a suction path (not shown) is disposed with one end connected to a suction source (not shown) and the other end connected to the porous member 28a.

When an object to be cleaned is placed on the holding table 28 and the suction source is operated to apply a negative pressure to the object to be cleaned via the suction path and the porous member 28a, the object to be cleaned is removed from the holding table 28 ) is maintained by suction. That is, the upper surface of the holding table 28 becomes a holding surface. The upper end of the output shaft 30 is connected to the lower part of the holding table 28, and a motor (not shown) is connected to the lower end of the output shaft 30. The output shaft 30 transmits the rotational force generated by the motor to the holding table 28 .

The washing water receiving mechanism 24 comprises an annular bottom wall 34 protruding radially inward from the bottom of the water case 16a, and a sheet metal raised from the bottom wall 34 outside the holding table 28. and a cylindrical outer circumferential wall 32 formed of a back. An output shaft 30 passes inside the bottom wall 34 along the vertical direction. A drainage port (not shown) is provided on the bottom wall 34, and a drainage channel leading to a waste liquid tank described later is connected to the drainage port. When the washing water falls into the washing water receiving mechanism 24, the washing water reaches a waste liquid tank 46 (see Fig. 3) described later through a drainage passage 44 (see Fig. 3) described later from the drain port.

A pipe-shaped shaft portion 36 of the cleaning mechanism 26 passes through the outer periphery of the bottom wall 34 . The shaft portion 36 is a pipe-shaped member that extends from the outside of the holding table 28 along a direction perpendicular to the upper surface of the holding table 28, and is positioned higher than the height of the upper surface of the holding table 28. , and two arm parts 38 are connected to the upper end. A motor (not shown) for rotating the shaft portion 36 is connected to the proximal side of the shaft portion 36, and the shaft portion 36 is rotated around the vertical direction by the motor.

The arm portion 38 is a pipe-shaped member extending in a direction perpendicular to the extension direction of the shaft portion 36 with a length corresponding to the distance from the shaft portion 36 to the center of the holding table 28, and each arm At the front end of the arm portion 38, a washing water supply nozzle 40 directed downward is disposed.

As will be described later, the washing device 2 includes a purification unit 42 serving as a washing water supply source, and flows from the washing water supply nozzle 40 to the holding table 28 via the shaft part 36 and the arm part 38. It has a function of ejecting washing water toward the object to be cleaned held in the to-be-cleaned and removing processing debris and the like attached to the object to be cleaned. For example, the washing water is pure water. In order to more powerfully clean the object to be cleaned, high-pressure gas may be mixed in the washing water supplied from the washing-water supply nozzle 40, and even if washing is performed with a mixed fluid of pure water and high-pressure gas in the washing device 2 good night.

On the outer circumferential side of the upper part of the holding table 28, a clamp 28b holding a ring frame of a frame unit having an object to be cleaned is disposed. In the clamp 28b, when the lower spindle portion moves toward the outer circumference due to the centrifugal force generated by the rotation of the holding table 28, the upper holding portion automatically collapses toward the inner circumferential side to grip the ring frame.

When cleaning the object to be cleaned with the cleaning unit 20, the object to be cleaned is sucked and held by the holding table 28, the holding table 28 is rotated at a high speed, and the shaft portion 36 is rotated to provide washing water. The supply nozzle 40 is reciprocally moved above the holding table 28. Then, the cleaning fluid (typically, a mixed fluid of pure water and high-pressure air) is injected from the cleaning water supply nozzle 40 toward the object to be cleaned. In doing so, the object to be cleaned is washed.

The used washing water that is sprayed onto the object to be cleaned and collects the processing waste falls on the bottom wall 34 of the washing water receiving mechanism 24 and is discharged to the outside of the washing space 16 through the drain. Conventionally, used washing water is disposed of by being discharged to the outside of the washing device 2 as waste liquid. However, the amount of pure water used in the cleaning device 2 is large, and a non-negligible cost is required to dispose of the waste liquid.

Therefore, a pure water generating device for generating pure water by purifying the waste liquid discharged from the cleaning device 2 is installed near the cleaning device 2 and used. The pure water generating device produces pure water by, for example, filtering waste liquid to produce fresh water, irradiating the fresh water with ultraviolet rays to destroy organic matter, and removing impurity ions from the fresh water using an ion exchange resin. Then, the generated pure water is supplied to the cleaning device 2 .

However, conventionally, when installing the pure water generating device adjacent to the cleaning device 2, it was necessary to secure an installation space for the pure water generating device in the vicinity of the processing device. This is because, if the pure water generating device is installed at a location away from the washing device 2, it is difficult to manage the quality of the pure water produced in the pure water generating device and moving to the washing device 2.

Further, the pure water generating device needs to include a pump mechanism for sending pure water to the cleaning device 2 regardless of the distance from the cleaning device 2 . And, the washing device 2 needs to be provided with a pump mechanism for supplying washing water to the object to be cleaned. In this way, it is necessary to operate a plurality of pump mechanisms in order to supply pure water regenerated from the waste liquid as washing water to the object to be cleaned, which sometimes becomes a factor in reducing the cleaning efficiency of the object to be cleaned.

Therefore, the cleaning device 2 according to the present embodiment includes the purification unit 42 at the bottom of the inner space of the housing 4 . The purification unit 42 purifies the used washing water to generate pure water, and sends pure water having a water quality satisfying a predetermined level to the washing space 16 as the washing water. Next, the purification unit 42 will be described.

3 is a configuration diagram schematically showing the configuration of the purification unit 42 and the connection relationship between the components. In FIG. 3, for convenience of description, a part of the passage is shown simplified linearly. The flow path is constructed with, for example, metal or resin piping, tubes, and the like.

The purification unit 42 includes a drainage channel 44 and a waste liquid tank 46 provided at an end of the drainage channel 44 . The washing water (waste liquid) discharged from the washing space 16 is supplied to the waste liquid tank 46 via the drainage channel 44 and stored therein. Specifically, foreign matter such as processing waste and water containing impurity ions are supplied to the waste liquid tank 46 as waste liquid.

The waste liquid tank 46 is connected to a waste liquid pump 48 that pumps up and discharges the waste liquid stored in the waste liquid tank 46 . The waste liquid pump 48 is a pump that supplies water (waste liquid) stored in the waste liquid tank 46 to the filter 50 . The amount of water supplied from the waste tank 46 to the filter 50 is controlled by the waste pump 48 .

The filter 50 is formed of, for example, activated carbon, zeolite, cloth, resin fiber, glass fiber, metal mesh, reverse osmosis membrane (RO membrane), or the like. Then, the filter 50 removes impurities such as processing debris contained in the waste liquid pumped up by the waste liquid pump 48 by adsorbing them or filtering them. That is, the waste liquid is filtered and purified into fresh water. The fresh water filtered by the filter 50 is accommodated in the fresh water tank 52 capable of accommodating the fresh water.

Inside the fresh water tank 52, an ultraviolet light source 54 for irradiating ultraviolet rays to the fresh water accommodated in the fresh water tank 52 is installed. The ultraviolet light source 54 is, for example, an ultraviolet lamp, an ultraviolet fluorescent lamp, or an ultraviolet LED. Microorganisms floating in the air are mixed as impurities in the water used in the cleaning device 2, for example. Thus, the ultraviolet light source 54 may irradiate the water with ultraviolet rays for sterilization of fresh water. In addition, when the fresh water is irradiated with ultraviolet rays, other organic substances included in the fresh water can be destroyed.

Here, the ultraviolet rays irradiated by the ultraviolet light source 54 to the fresh water may include a component having a wavelength of 254 nm and a component having a wavelength of 185 nm. When the fresh water is irradiated with ultraviolet rays having a wavelength of 254 nm, the fresh water can be sterilized. When microbes die, their dead bodies arise in the water. In addition, other organic substances are also mixed in the fresh water. Ultraviolet light with a wavelength of 185 nm activates ozone contained in fresh water and promotes decomposition of organic matter by ozone.

A fresh water pump 56 is connected to the fresh water tank 52 via a flow path. The fresh water pump 56 has a function of pumping fresh water from the fresh water tank 52 and sending it to the downstream side of the flow path. Further, the ultraviolet light source 54 may be provided in a passage through which the fresh water pumped up by the fresh water pump 56 flows, or ultraviolet light may be irradiated from the ultraviolet light source 54 to the fresh water flowing through the passage.

An ion exchange resin unit 58 is connected to the downstream side of the fresh water tank 52 in the flow path. The ion exchange resin unit 58 includes an ion exchange resin, and exchanges ions included in water irradiated with ultraviolet rays by the ultraviolet light source 54 . The ion exchange resin unit 58 has, for example, a cylindrical container and an ion exchange resin filled in the container. A flow path through which water travels between ion exchange resins is formed inside the vessel, and water entering the ion exchange resin unit 58 passes between the ion exchange resins in the vessel.

For example, an ion exchange resin for exchanging cations (cation exchange resin) and an ion exchange resin for exchanging anions (anion exchange resin) are accommodated in a mixed state in the container. Among the ions contained in the water supplied to the ion exchange resin unit 58, ions other than hydrogen ions and hydroxide ions are exchanged for hydrogen ions or hydroxide ions. That is, the ion exchange resin unit 58 purifies pure water by bringing the fresh water pumped up by the fresh water pump 56 into contact with the ion exchange resin.

The outlet of the ion exchange resin unit 58 is connected to a flow path, and water (pure water) whose ions have been exchanged by the ion exchange resin travels through the flow path and reaches the precision filter 60 . The precision filter 60 has a function of finally filtering the water (pure water) in which ions have been exchanged by the ion exchange resin unit 58.

Like the filter 50, the precision filter 60 includes a filter (not shown) formed of, for example, activated carbon, zeolite, cloth, resin fiber, glass fiber, metal mesh, reverse osmosis membrane (RO membrane), or the like. do.

The water discharged as waste liquid from the cleaning device 2 is purified while passing through the flow path of the purification unit 42, and is the final stage of purification when it reaches the fine filter 60. Since the amount of impurities contained in the water is very small, the precision filter 60 is required to have performance suitable for removing such impurities. For example, a finer film than the filter 50 may be used for the precision filter 60 .

The precision filter 60 further purifies the water by adsorbing or filtering a very small amount of impurities contained in the inflowing water. The water (pure water) filtered by the precision filter 60 proceeds to the downstream side of the passage and reaches the resistivity meter 62 that measures the resistivity value of the water (pure water).

The specific resistance of water increases as the amount of impurities contained in the water decreases. Therefore, by measuring the resistivity of water (pure water) with the resistivity meter 62, it is possible to determine whether or not the purified pure water is of a water quality that can be reused in the washing device 2 as washing water. For example, the resistivity meter 62 is connected to the control unit 8, and the control unit 8 registers a critical value for determining the resistivity value that can be used as washing water. The control unit 8 determines the quality of the pure water based on the specific resistance value of the pure water transmitted from the resistivity meter 62.

The purification unit 42 includes a switching valve 66 at an end of a flow path 64 through which water (pure water) whose specific resistance value is measured by the specific resistance value meter 62 flows. In the switching valve 66, a first flow path 68 leading to the waste liquid tank 46 and a second flow path 70 leading to the washing water supply nozzle 40 of the washing space 16 are connected. The switching valve 66 is a solenoid valve connected to the control unit 8, for example. The switching valve 66 has a function of switching the outflow destination of water flowing in through the flow path 64 to one of the first flow path 68 and the second flow path 70 .

The control unit 8 controls the quality of the water (pure water) as washing water for washing the object to be cleaned when the resistivity value of the water (pure water) measured by the resistivity meter 62 does not exceed a predetermined threshold value. It is judged that the usable level is not satisfied. In this case, if the water is sent to the washing water supply nozzle 40 in this state, washing water of a water quality that does not satisfy the predetermined level is supplied to the object to be cleaned, and the object to be cleaned cannot be sufficiently washed.

Therefore, the control unit 8 controls the switching valve 66 to switch the outflow destination of the water to the first flow path 68 and sends the water (pure water) to the waste liquid tank 46 . In this case, water having a quality that does not meet the predetermined level flows again through the flow path of the purification unit 42 together with the water stored in the waste liquid tank 46 and is further purified. In this case, the water stored in the waste liquid tank 46 is gradually purified.

Then, when the resistivity value of the water (pure water) measured by the resistivity meter 62 gradually increases and exceeds a predetermined threshold value, the control unit 8 controls the quality of the water (pure water) to clean the object to be cleaned. It is judged that the usable level as washing water is satisfied. At this time, the control unit 8 controls the switching valve 66 to switch the outflow destination of the water to the second flow path 70 . Then, pure water confirmed to have a predetermined level of water quality is supplied as washing water to the washing water supply nozzle 40, and the washing water is supplied from the washing water supply nozzle 40 to the object to be cleaned.

Next, the cleaning operation of the object to be cleaned in the cleaning device 2 will be described. When washing the object to be cleaned, first, the holding table 28 of the spinner table mechanism 22 sucks and holds the object to be cleaned, and rotation of the holding table 28 is started, and the washing water supply nozzle 40 ) is moved back and forth from the top of the object to be cleaned.

Next, the operation of the purification unit 42 is started to start water purification, and pure water satisfying a predetermined level of water quality is sent as washing water to the washing water supply nozzle 40, and the water is discharged from the washing water supply nozzle 40. The washing water is supplied to the washing object. At this time, a high-pressure gas may be mixed with the washing water, or two fluids may be ejected from the washing water supply nozzle 40 .

The washing water supplied to the object to be cleaned collects processing debris and the like adhering to the surface of the object to be cleaned and reaches the waste liquid tank 46 of the purification unit 42 . Then, while the purification unit 42 is operating, the water accumulated in the waste liquid tank 46 is purified, is reproduced as washing water, and is supplied from the washing water supply nozzle 40 to the object to be cleaned again.

At this time, when the resistivity value of the water measured by the resistivity meter 62 decreases and falls below a predetermined threshold value, the control unit 8 controls the switching valve 66 to set the water outlet destination to the second flow path 70. is switched to the first flow passage 68, and the supply of water to the washing water supply nozzle 40 is stopped. In this case, since the supply of water that does not satisfy the predetermined level to the object to be cleaned can be prevented, re-contamination of the object to be cleaned can be prevented.

Then, while the operation of the purification unit 42 continues, when the specific resistance value of the water measured by the specific resistance value meter 62 increases and exceeds a predetermined dark limit value, the control unit 8 controls the switching valve 66 to The water outlet destination is switched from the first flow path 68 to the second flow path 70 . That is, the supply of water to the washing water supply nozzle 40 is resumed, and washing water whose water quality satisfies a predetermined level is supplied to the object to be cleaned.

When the washing water is sprayed on the object to be cleaned for a predetermined time, the supply of the washing water from the washing water supply nozzle 40 is stopped, and the rotation of the holding table 28 is continued to dry the object to be washed. In doing so, washing of the object to be cleaned is completed. After the object to be cleaned is sufficiently dried, the rotation of the holding table 28 is ended, and the suction holding of the object to be cleaned by the holding table 28 is released. Then, the object to be cleaned is taken out of the cleaning device 2 .

In addition, if the cleaning device 2 continues to clean the object to be cleaned, a part of the circulating water may volatilize and the cleaning device 2 may run out of water. In this case, the manager of the washing device 2 can maintain the circulation of a predetermined amount of water in the washing device 2 by periodically supplying and replenishing water into the washing water receiving mechanism 24 . In addition, the washing device 2 may be connected to a water supply pipe connected to a water supply source, and water may be supplied through the water supply pipe when the amount of water circulating therein decreases.

As described above, according to the washing device 2 according to the present embodiment, as in the case of using an independent pure water generating device, in the vicinity of the processing device, in addition to the installation space of the washing device 2, the pure water generating device is installed. No need to reserve space. In addition, since the passage from the purification unit 42 to the washing water supply nozzle 40 can be made very short, and the quality of the washing water can be checked immediately before it reaches the washing water supply nozzle 40, Water quality management is also very easy.

Further, in the case of connecting an independent pure water generating device to the washing device as in the prior art, the pure water generating device needs to include a pump mechanism for supplying pure water to the washing device, and a pump for supplying the washing water to the washing water supply nozzle. It was necessary to have the cleaning device equipped with the mechanism. In contrast, in the washing device 2 according to the present embodiment, the fresh water pump 56 of the purification unit 42 serves as both pump mechanisms and serves as a driving source for supplying washing water. Therefore, since washing water can be supplied to the object to be cleaned with a simple configuration and the water supply cost can be reduced, the cleaning efficiency of the object to be cleaned can be increased.

It is also conceivable to supply the processed water to the workpiece or the processing unit while purifying and regenerating the processing water used in the processing unit by incorporating the purification unit 42 into the processing unit that processes the workpiece. However, when the quality of the recycled water during processing of the workpiece does not satisfy a predetermined level, continuing to supply the processing water as it is causes a problem because the predetermined processing quality cannot be maintained. On the other hand, if the supply of processing water is stopped during processing of the workpiece, it becomes a problem because the predetermined processing quality cannot be maintained.

In contrast, in the cleaning apparatus 2 according to the present embodiment, when the water quality of the water regenerated in the purification unit 42 does not satisfy a predetermined level while cleaning the object to be cleaned, the object to be cleaned is cleaned. Even if the supply of water is stopped, it is unlikely to become a big problem. If the purification of water is continued by the purification unit 42 and the supply of washing water is resumed when the water quality meets the predetermined level, and finally the predetermined washing process can be performed, the object to be cleaned can be sufficiently cleaned. can

That is, in the cleaning device 2 according to the present embodiment, the object to be cleaned can be washed without problems even when the supply of the washing water becomes unstable. This can be said to be the reason why a pure water tank for storing purified water and a pump mechanism serving as a supply driving source of washing water from the pure water tank to the washing water supply nozzle 40 can be omitted.

However, the washing device 2 according to the present embodiment may have such a pure water tank and a pump function. For example, when the washing device 2 has a pure water tank or the like, it is possible to store pure water having a water quality that satisfies a predetermined level, so that the washing water supply nozzle 40 can stably supply the washing water continuously. In addition, when temperature control of the washing water is required, the temperature of the washing water can be adjusted by providing a temperature control mechanism such as a heat source such as a heating wire or a cooling source such as a Peltier element in the pure water tank.

Further, in the above embodiment, a case has been described in which the cleaning device 2 has the switching valve 66 and returns water whose water quality does not meet a predetermined level to the waste tank 46, but one aspect of the present invention is not limited to this. That is, the cleaning device 2 may not include the switching valve 66 and the first flow path 68 . Unlike the processed water used in the processing equipment that processes the workpiece, the washing water supplied to the object to be cleaned in the cleaning device 2 may cause damage to the object to be cleaned even if the water quality does not meet the predetermined level. difficult.

In this case, for example, the end condition for cleaning the object to be cleaned is that pure water, which has been confirmed to satisfy a predetermined level by the specific resistance value measured by the resistivity meter 62, is continuously supplied to the object to be cleaned for a period exceeding a predetermined time. can think of doing In this case, when the quality of the water supplied to the object to be cleaned does not satisfy the predetermined level, the count of the washing time is set to zero, and when it is confirmed that the quality of the water meets the predetermined level, the count of the washing time is restarted, and the washing It is good to end the washing when the time exceeds the predetermined time.

In this way, even when the cleaning device 2 does not include the selector valve 66, the object to be cleaned can be sufficiently washed. In this case, since water is continuously supplied to the object to be cleaned, there is no fear that the object to be cleaned is dried during the cleaning process of the object to be cleaned.

Further, in the above embodiment, the case where the cleaning device 2 is installed adjacent to the processing device has been described as an example, but the cleaning device 2 according to the present embodiment is not limited to this. That is, the cleaning device 2 may be used by being incorporated in a processing device that processes a workpiece.

In addition, the structure, method, etc. according to the above embodiment can be appropriately changed and implemented without departing from the objective scope of the present invention.

2: cleaning device 4: housing
6: opening and closing cover 8: control unit
8a: Porous member 10: Display with touch panel
12: alarm lamp 14: support leg
16: cleaning space 16a: water case
18: emergency stop button 20: cleaning unit
22: spinner table mechanism 24: washing water receiving mechanism
26: cleaning mechanism 28: holding table
28a: porous member 28b: clamp
30: output shaft 32: outer circumferential wall
34: bottom wall 36: shaft
38: arm part 40: washing water supply nozzle
42: purification unit 44: drainage
46: waste tank 48: waste pump
50: filter 52: fresh water tank
54: ultraviolet light source 56: fresh water pump
58: ion exchange resin unit 60: precision filter
62: resistivity value meter 64: Euro
66: conversion valve 68: first flow path
70: 2nd Euro

Claims (5)

A washing device that cleans an object to be cleaned using washing water, recovers waste liquid, and regenerates and circulates pure water,
a holding table for holding an object to be cleaned;
a washing water supply nozzle supplying washing water to the object to be cleaned held on the holding table;
A waste liquid tank accommodating washing water used for washing an object to be cleaned as a waste liquid;
A waste liquid pump for pumping up the waste liquid from the waste liquid tank;
A filter for filtering the waste liquid pumped up by the waste liquid pump and purifying it into fresh water;
A fresh water tank accommodating the fresh water;
An ultraviolet light source for irradiating ultraviolet rays to the fresh water;
A fresh water pump pumping the fresh water from the fresh water tank;
An ion exchange resin unit for purifying pure water by bringing the fresh water pumped up by the fresh water pump into contact with an ion exchange resin;
Resistivity value meter for measuring the specific resistance value of the pure water
Cleaning device characterized in that it comprises a. The method of claim 1, wherein the maintenance table, the washing water supply nozzle, the waste liquid tank, the waste liquid pump, the filter, the fresh water tank, the ultraviolet light source, the fresh water pump, and the ion A cleaning device characterized by comprising an exchange resin unit and a housing accommodating the resistivity value meter. The cleaning device according to claim 1 or 2, further comprising a precision filter for filtering pure water purified by the ion exchange resin unit and before the specific resistance value is measured with the resistivity meter. The method of claim 1 or 2, which is connected to a first flow path leading to the waste tank and a second flow path leading to the washing water supply nozzle, and determines the outflow destination of the pure water based on the specific resistance of the pure water. A cleaning device further comprising a switching valve for switching between the first flow path and the second flow path. The method of claim 4, wherein the fresh water pump functions as a supply driving source for supplying the pure water to the washing water supply nozzle when the switching valve sets the pure water outlet destination as the second flow path. cleaning device.

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