JP2010021215A - Cleaning system and method for circulating cleaning fluid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning system and a method for circulating the cleaning fluid which can limit the exchange frequency of a filter. <P>SOLUTION: A cleaning system comprises a cleaning tub 11 which receives cleaning fluid 101 containing sulphuric acid and hydrogen peroxide solution, a cleaning circulation line 29 through which the cleaning fluid 101 can be discharged from the outlet of the cleaning tub 11, and passed through heating equipment 21 and a filter 25 or a bypass line 28 before being returned to the inlet of the cleaning tub 11, and a regenerating circulation line 55 through which heated cleaning fluid 101 can be discharged from the outlet of the cleaning tub 11, passed through a cooler 33, introduced to the inlet of a regeneration tub 35 which raises the concentration of sulphuric acid to a predetermined level by heating, discharged from the outlet of the regeneration tub 35, passed through a cooler 41, and stored in a buffer tub 51 before being returned from the buffer tub 51 to the inlet of the cleaning tub 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning system and a cleaning liquid circulation method for cleaning a semiconductor wafer.

  Cleaning treatments such as resist stripping of the semiconductor wafer and removal of organic substances are usually performed by immersing the semiconductor wafer in a cleaning solution in a cleaning tank.

As the cleaning liquid, a mixed liquid of sulfuric acid and hydrogen peroxide water (SPM cleaning liquid, sulfuric acid-hydrogen peroxide mixture) is used. For example, in the case of resist peeling, the cleaning liquid is kept at a high temperature of 100 ° C. or higher in order to improve the resist peeling property. The boiling point of hydrogen peroxide water (H ₂ O ₂ ) is about 150 ° C., but at a high temperature of 100 ° C. or higher, the generation of water (H ₂ O) and oxygen (O ₂ ) proceeds by thermal decomposition. That is, in the SPM cleaning liquid, water gradually increases due to thermal decomposition and the sulfuric acid concentration decreases, so that the cleaning ability is reduced by the oxidizing power, that is, the resist stripping property is weakened.

  Therefore, a technique for increasing the sulfuric acid concentration of the SPM cleaning liquid in which the sulfuric acid concentration is reduced, and regeneration of the SPM cleaning liquid are performed. For example, a quartz glass reaction tank (regeneration tank) is filled with a wafer cleaning solution (SPM cleaning solution) with reduced cleaning ability, heated to 150 to 315 ° C., and decomposed with residual hydrogen peroxide solution and hydrogen peroxide solution. After removing the water, etc., and concentrating sulfuric acid to make concentrated sulfuric acid, it is cooled to about 80 ° C in a cooling tank, and the wafer cleaning liquid containing concentrated sulfuric acid is returned to the wafer processing tank (cleaning tank) again to clean the wafer. A sulfuric acid recycling apparatus (cleaning system) that is reused is disclosed (for example, see Patent Document 1). The SPM cleaning liquid having concentrated sulfuric acid in the wafer processing tank can be circulated between the inner tank and the outer layer of the cleaning tank through a filter by a raw material transport pump.

The disclosed cleaning system concentrates and reuses the sulfuric acid of the SPM cleaning solution, but after regeneration, the SPM cleaning solution having concentrated sulfuric acid precipitates the dissolved resist component when the temperature decreases. When the SPM cleaning liquid containing cooled concentrated sulfuric acid is sent to the cleaning tank and circulated through the inner tank and the outer layer of the cleaning tank through the filter, the resist component is captured by the filter, the filter is clogged, and the flow rate is reduced. There arises a problem that the replacement frequency of the filter is increased.
JP 2002-68715 A (pages 4 to 6, FIG. 1)

  The present invention provides a cleaning system and a cleaning liquid circulation method capable of suppressing the frequency of filter replacement.

  The component cleaning system according to one aspect of the present invention includes a cleaning tank that contains a cleaning liquid containing a first chemical liquid and a second chemical liquid, and the cleaning liquid is discharged from an outlet of the cleaning tank and passes through a heating unit. The cleaning circulation line returned to the introduction port of the cleaning tank after passing through the filtering means or the bypass means used by switching, and the cleaning liquid are discharged from the discharge port of the cleaning tank, and the first cooling After passing through the means, it is introduced into the introduction port of the regeneration tank that raises the concentration of the first chemical liquid to a predetermined concentration by heating, is discharged from the discharge port of the regeneration tank, and passes through the second cooling means. And a regeneration circulation line stored in the buffer tank and returned from the buffer tank to the inlet of the cleaning tank.

  Further, in the cleaning system according to another aspect of the present invention, the cleaning tank containing the cleaning liquid containing the first chemical liquid and the second chemical liquid, and the heated cleaning liquid are discharged from the discharge port of the cleaning tank, A cleaning circulation line that passes through the first heating means, passes through the filtering means, and is returned to the inlet of the cleaning tank, and the cleaning liquid is discharged from the outlet of the cleaning tank, and the first cooling means Is passed through the inlet of the regeneration tank that raises the concentration of the first chemical liquid to a predetermined concentration by heating, is discharged from the outlet of the regeneration tank, passes through the second cooling means And a regeneration circulation line that is stored in the buffer tank and passes from the buffer tank through the second heating means disposed close to the inlet of the cleaning tank and returned to the inlet of the cleaning tank. It is characterized by that.

  Moreover, the cleaning liquid circulation method according to another aspect of the present invention is a circulation in which the cleaning liquid containing the first chemical liquid and the second chemical liquid is discharged from the cleaning tank and returned to the cleaning tank through the heating means and the filtering means. Performing a cleaning process at a cleaning process temperature higher than room temperature, and transferring the cleaning liquid having a reduced concentration of the first chemical solution to a regeneration tank after being cooled by a first cooling means. The step of regenerating the cleaning liquid by increasing the concentration of the first chemical liquid to a predetermined concentration at a temperature higher than the processing temperature, and the regenerated cleaning liquid is cooled by the second cooling means, transferred to the buffer tank, and regenerated. A step of transferring the cleaning liquid from the buffer tank to the cleaning tank, and a circulation of discharging the regenerated cleaning liquid from the cleaning tank and returning it to the cleaning tank through the heating means and the bypass means bypassing the filtering means. Conduct Characterized by a step of increasing the serial cleaning process temperature.

  Moreover, the cleaning liquid circulation method according to another aspect of the present invention is configured to discharge the cleaning liquid containing the first chemical liquid and the second chemical liquid from the cleaning tank and pass the first heating means and the filtering means to the cleaning tank. Performing a return circulation, performing a cleaning process at a cleaning process temperature higher than room temperature, and transferring the cleaning liquid having a reduced concentration of the first chemical solution to the regeneration tank after being cooled by the first cooling means; A step of increasing the concentration of the first chemical liquid to a predetermined concentration at a temperature higher than the cleaning treatment temperature and regenerating the cleaning liquid; cooling the regenerated cleaning liquid with a second cooling means; And a step of transferring the regenerated cleaning liquid from the buffer tank to the cleaning tank via a second heating means.

  ADVANTAGE OF THE INVENTION According to this invention, the washing | cleaning system and washing | cleaning-liquid circulation method which can suppress the replacement frequency of a filter can be provided.

  In each of the following examples, a case where an SPM cleaning liquid that is a mixed liquid of sulfuric acid and hydrogen peroxide solution is selected as the cleaning liquid will be described. However, when the temperature is lowered, other chemical liquids in which a solid such as a dissolved resist component is precipitated. Of course, the same can be applied to the cleaning liquid composed of the above mixed liquid.

  Embodiments of the present invention will be described below with reference to the drawings. In the figure shown below, the same code | symbol is attached | subjected to the same component.

  A cleaning system and a cleaning liquid circulation method according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a configuration diagram schematically showing a cleaning system. FIG. 2 is a flowchart showing a schematic procedure of the cleaning liquid circulation method.

  As shown in FIG. 1, the cleaning system 1 includes a cleaning tank 11 that stores an SPM cleaning liquid (hereinafter referred to as a cleaning liquid 101) that is a mixed liquid of sulfuric acid that is a first chemical liquid and hydrogen peroxide water that is a second chemical liquid. Between the discharge port of the cleaning tank 11 and the introduction port of the cleaning tank 11, in order from the discharge port of the cleaning tank 11, a heating device 21 that is a heating means of the cleaning liquid 101 and a filter 25 that is a filtering means or a bypass means. A cooling device 33 which is a first cooling means in order from the outlet of the cleaning tank 11 between the cleaning circulation line 29 having a certain bypass line 28, and the outlet of the cleaning tank 11 and the inlet of the cleaning tank 11. And a regeneration tank 35 for increasing the sulfuric acid concentration of the cleaning liquid 101 to a predetermined concentration, a cooling device 41 as a second cooling means, and a regeneration circulation line 55 having a buffer tank 51.

  The cleaning tank 11 is, for example, a bottomed box type made of quartz glass and has a double structure including an inner tank 13 and an outer tank 14 arranged so as to surround the inner tank 13. The inner tank 13 stores a predetermined volume of cleaning liquid 101 so that a semiconductor wafer (not shown) can be immersed and cleaned. The stored cleaning liquid 101 can overflow from the inner tank 13 to the outer tank 14. Although not shown, the cleaning tank 11 is supplied with sulfuric acid and hydrogen peroxide water through pipes connected to the inner tank 13 or the outer tank 14, respectively. The cleaning tank 11 can be entirely or partially made of fluororesin.

  Although not shown, the cleaning tank 11 includes a temperature sensor that measures the temperature of the cleaning liquid 101, a liquid level sensor that measures the liquid level of the cleaning liquid 101, a concentration sensor that measures the concentration of the cleaning liquid 101, and the like. . Further, the washing tank 11 can be provided with an auxiliary washing tank heater for heating the cleaning liquid 101 at the outer bottom or the inner bottom.

  The cleaning circulation line 29 connects the discharge port piped to the outer tank 14 and the inlet port piped to the inner tank 13 below the cleaning tank 11. The outlet of the outer tub 14 is connected to one end of the pump 17, and the other end of the pump 17 is connected to one end of the heating device 21 via the valve 19. The other end of the heating device 21 is branched into two, one connected to one end of the filter 25 via the valve 23, and the other connected to one end of the bypass line 28 having the valve 27. The other end of the filter 25 and the other end of the bypass line 28 are connected to each other and connected to the inlet of the inner tank 13. The cleaning circulation line 29 is arranged in the vicinity of the cleaning tank 11 so that the piping distance is as short as possible in order to circulate the cleaning liquid 101 at a high temperature (for example, about 120 ° C.).

  The pump 17 applies pressure to circulate the cleaning liquid 101 from the outer tank 14 to the inner tank 13. The filter 25 removes particles above a certain level in the cleaning liquid 101. The bypass line 28 has a pipe having an inner diameter similar to that of the cleaning circulation line 29, and the filter 25 can be bypassed by opening the valve 27 and closing the valve 23.

  The cleaning liquid 101 is supplied in such an amount that the inner tank 13 is filled and the cleaning circulation line 29 is continuously driven during the cleaning process.

  The cleaning liquid 101 is heated by the heating device 21 and reaches a predetermined temperature (for example, about 120 ° C. in the inner tank 13). When the semiconductor wafer is being cleaned, the valve 27 is closed, the valve 23 is opened, and the cleaning liquid 101 is circulated through the filter 25.

  Next, the regeneration circulation line 55 includes a discharge port connected to the outer tank 14 and a discharge port connected to the inner tank 13 below the cleaning tank 11, and an introduction port connected to the inner tank 13 below the cleaning tank 11. Is connected. The outlet of the inner tank 13 via the valve 16 and the outlet of the outer tank 14 are both connected to one end of the pump 17, and the other end of the pump 17 is connected to one end of the cooling device 33 via the valve 31. Has been. The other end of the cooling device 33 is connected to one end of the regeneration tank 35, and the other end of the regeneration tank 35 is connected to one end of the cooling device 41. The other end of the cooling device 41 is connected to one end of a buffer tank 51 for storage, the other end of the buffer tank 51 is connected to one end of a pump 53, and the other end of the pump 53 is an inlet of the inner tank 13. It is connected to the.

  From the outlet port piped to the outer tub 14 to the branch of the valve 19 and the valve 31 at the other end of the pump 17, it is shared with the cleaning circulation line 29. In addition, although the height difference is utilized from the discharge port of the regeneration tank 35 to the inlet port of the buffer tank 51, it is possible to provide a pump in the meantime.

  There is a possibility that the cleaning liquid 101 is hot from the cleaning tank 11 to the cooling device 33, and the piping between them is arranged in the vicinity of the cleaning tank 11 so that the piping distance is as short as possible, like the cleaning circulation line 29. ing. That is, the cooling device 33 is disposed in the vicinity of the cleaning circulation line 29.

  The cooling device 33 has, for example, a structure in which the cleaning liquid 101 inside the pipe of the regeneration circulation line 55 is removed by a coolant such as water disposed outside the pipe, and the cleaning liquid 101 can be cooled to 50 ° C. or lower. Is possible. More preferably, the cooling device 33 can cool to room temperature. The cooling device 33 is necessary for safety when the distance from the cleaning tank 11 to the regeneration tank 35 is long, for example, when the regeneration tank 35 is placed downstairs.

  The regeneration tank 35 is made of quartz glass and is heated to 150 ° C. or higher to evaporate and remove water and hydrogen peroxide water generated by the decomposition of the hydrogen peroxide solution in the cleaning solution 101. It is possible to increase (regenerate) the concentration of sulfuric acid. The cleaning liquid 101 sent to the regeneration tank 35 at 50 ° C. or less is heated to, for example, 250 ° C. or more and discharged from the regeneration tank 35. In addition, the regeneration tank 35 may be made of quartz glass in part in contact with the cleaning liquid 101.

  The cooling device 41 has the same structure as the cooling device 33, for example, and can cool the regenerated cleaning liquid 101 to 50 ° C. or lower. More preferably, the cooling device 41 can cool to room temperature. The cooling device 41 is disposed in the vicinity of the regeneration tank 35 so that the piping distance is as short as possible.

  The buffer tank 51 is made of quartz glass or fluororesin, and has a size that can accommodate, for example, the capacity of the cleaning tank 11 and the cleaning liquid 101 full of the cleaning circulation line 29.

  The cleaning liquid 101 stored in the buffer tank 51 and regenerated at approximately room temperature is supplied with pressure by the pump 53 to the inner tank 13.

  The distance between the cooling device 33 and the regeneration tank 35 at which the temperature of the cleaning liquid 101 is 50 ° C. or less, and the distance from the cooling device 41 to the cleaning tank 11 can be relatively long. The buffer tank 51 can be arranged separately from the cleaning tank 11. As a result, the regeneration tank 35 and the buffer tank 51 can be connected to the plurality of cleaning tanks 11 and switched to regenerate the cleaning liquid 101.

  The above-described regeneration circulation line 55 operates based on the determination that the cleaning ability of the cleaning liquid 101 is reduced and regeneration is possible. When operating, the cleaning circulation line 29 other than the common part with the regeneration circulation line 55 is stopped. The cleaning liquid 101 in the inner tank 13 and the outer tank 14 is cooled by the cooling device 33 and sent to the regeneration tank 35 in accordance with the processing capacity of the regeneration tank 35. The cleaning liquid 101 that has been subjected to the high temperature treatment and regenerated in the regeneration tank 35 is cooled by the cooling device 41, sent to the buffer tank 51, and stored in the buffer tank 51. The cleaning liquid 101 collected in the buffer tank 51 is returned to the inlet of the inner tank 13 at a substantially room temperature.

  The cleaning circulation line 29 and the regeneration circulation line 55 have been described. Next, the cleaning circulation, the regeneration circulation, and the circulation for heating the cleaning liquid 101 performed between these two circulations are added to the entire cleaning system 1. A cleaning liquid circulation method will be described.

  As shown in FIG. 2, the cleaning circulation line 29 passing through the filter 25 is operated, and the cleaning liquid 101 is circulated between the outer tub 14 and the inner tub 13, and the temperature that moves in the decreasing direction is heated by the heating device 21. Then, it is managed at a predetermined cleaning processing temperature (for example, about 120 ° C. in the inner tank 13) (step S11). The valve 19 and the valve 23 in the cleaning circulation line 29 are opened, and the valve 27 is closed. The valves 16 and 31 in the regeneration circulation line 55 are closed.

  A cleaning lot made of a semiconductor wafer is put into the inner tank 13 to clean, for example, a resist on the surface of the semiconductor wafer (step S12).

  After the cleaning process, the cleaning lot is carried out from the inner tank 13 (step S13).

  Based on the number of cleaning processes of the cleaning liquid 101 and / or measurement of the specific gravity of the cleaning liquid 101, it is determined whether the cleaning liquid 101 can be used continuously, needs to be regenerated, or cannot be used (step S14).

  When it is necessary to regenerate, the cleaning liquid 101 in the inner tank 13 and the outer tank 14 is cooled by the cooling device 33 and then transferred to the regeneration tank 35 (step S15). The valve 19 in the cleaning circulation line 29 is closed, and the valves 16 and 31 in the regeneration circulation line 55 are opened. When the capacity of the regeneration tank 35 is small, for example, an amount of the cleaning liquid 101 suitable for the regeneration tank 35 is sent by opening and closing the valve 31.

  The cleaning liquid 101 is treated at a high temperature at 250 ° C. or higher in the regeneration tank 35 to increase (regenerate) the sulfuric acid concentration (step S16).

  The regenerated cleaning liquid 101 is cooled by the cooling device 41 and then transferred to the buffer tank 51 (step S17).

  The regenerated cleaning liquid 101 is transferred from the buffer tank 51 to the inner tank 13 (step S18).

  After the valve 23 is closed and the filter 25 is disabled, the valve 27 is opened and set to pass through the bypass line 28, the cleaning circulation line 29 is operated, and the heating device 21 raises the temperature of the cleaning liquid 101 (step S19). ). While the cleaning liquid 101 is circulated through the cleaning circulation line 29, the temperature of the cleaning liquid 101 is increased, and the deposited resist components are dissolved again.

  After step S19, the process returns to step S11. That is, the cleaning circulation line 29 is switched from the bypass line 28 to a line passing through the filter 25.

  If it is determined in step S14 that the cleaning liquid 101 can be used continuously, the process returns to step S11.

  If it is determined in step S14 that the cleaning liquid 101 cannot be used, the cleaning liquid 101 is discharged as waste liquid from a discharge port provided in another line or the cleaning circulation line 29 and processed (step S20). Although not shown, after the cleaning liquid 101 is treated as a waste liquid, the cleaning tank 11 is replenished with a new cleaning liquid 101, and then the process starts from step S11.

  As described above, the regenerated cleaning liquid 101 at approximately room temperature is returned to the cleaning tank 11 and circulated through the bypass line 28 during the temperature rise, so that there is no possibility of clogging the filter 25 and the cleaning processing temperature is reached. Then, it is switched and circulates in the cleaning circulation line 29 passing through the filter 25. At this stage, since the deposited resist component is redissolved, the possibility that the resist component clogs the filter 25 is suppressed.

  That is, the regenerated cleaning liquid 101 is circulated through the bypass line 28 until the deposited resist is redissolved and passes through the filter 25 after reaching the cleaning processing temperature. Therefore, the cleaning system 1 filters the resist component in the cleaning liquid 101. The frequent exchange of 25 can be suppressed. Further, even if the resist component in the cleaning liquid 101 increases, it is dissolved again within the solubility, so that the cleaning liquid 101 can be used multiple times.

  Further, since the cooling device 33 is disposed in the regeneration circulation line 55 of the cleaning system 1, the cleaning liquid 101 that has passed through the cooling device 33 can be safely transferred to a relatively long distance. As a result, the one set of the regeneration tank 35 and the buffer tank 51 can be connected to the plurality of cleaning tanks 11 and switched to regenerate the cleaning liquid 101 with a time difference. When a plurality of cleaning tanks 11 are required, the cleaning system 1 can be configured as a more efficient system. Moreover, since the washing tank 11, the regeneration tank 35, the buffer tank 51, and the like can be placed apart from each other, the degree of freedom in the layout of the production line and the like is increased.

  A cleaning system and a cleaning liquid circulation method according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 3 is a configuration diagram schematically showing the cleaning system. FIG. 4 is a configuration diagram schematically showing a preheating device of the cleaning system. The cleaning circulation line passes through the filter, and the regeneration circulation line is different from the first embodiment in that a preheating device is connected. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof will be omitted, and different components will be described.

  As shown in FIG. 3, the cleaning system 2 includes heating that is a first heating unit in order between the cleaning tank 11 that stores the cleaning liquid 101, and the discharge port of the cleaning tank 11 and the introduction port of the cleaning tank 11. Regeneration in which the sulfuric acid concentration of the cooling device 33 and the cleaning liquid 101 is increased to a predetermined concentration in order between the cleaning circulation line 71 having the apparatus 21 and the filter 25, and the discharge port of the cleaning tank 11 and the introduction port of the cleaning tank 11. A tank 35, a cooling device 41, a buffer tank 51, and a regeneration circulation line 75 having a preheating device 73 as a second heating means are provided.

  The cleaning circulation line 71 is different from the cleaning circulation line 29 of the cleaning system 1 of the first embodiment in that the bypass line 28 is removed and the valve 23 disposed immediately before the filter 25 is removed. .

  The regeneration circulation line 75 differs from the regeneration circulation line 55 of the cleaning system 1 of the first embodiment in that the delivery side of the pump 53 introduces the inner tank 13 below the cleaning tank 11 via the preheating device 73. It is piped to the mouth. Since the preheating device 73 sends out the heated cleaning liquid 101, the preheating device 73 is disposed in the vicinity of the cleaning tank 11.

  As shown in FIG. 4, the preheating device 73 includes a heating tank 77 having an introduction port for introducing the cleaning liquid 101 from the regeneration circulation line 75, a discharge port piped to the heating tank 77, a pump 81, a valve 83, And a heating circulation line 87 that passes through the heating device 79 in order and returns to the inlet port piped to the temperature raising tank 77. The heating circulation line 87 is branched between the pump 81 and the valve 83 and is connected to the cleaning tank 11 via the valve 85 and the regeneration circulation line 75.

  After the cleaning liquid 101 at substantially room temperature is introduced from the regeneration line 75 into the heating tank 77, pressure is applied by the pump 81, the heated valve 83 passes through the opened valve 83, and the heating tank 79 is heated. Returned to the entrance. When the cleaning liquid 101 is heated, the valve 85 is closed. The cleaning liquid 101 at a predetermined temperature is sent to the inlet of the inner tank 13 through the regeneration line 75 branched from the heating circulation line 87 with the valve 85 opened and the valve 83 closed. The cleaning liquid 101 can be raised to a temperature necessary for the cleaning process in the inner tank 13.

  Next, a cleaning circulation, a regeneration circulation, and a circulation for heating the cleaning liquid 101 performed between these two circulations are added, and the entire cleaning liquid circulation method of the cleaning system 3 is based on the flowchart shown in FIG. The different parts will be explained.

  As in step S11 shown in FIG. 2, the cleaning circulation line 71 passing through the filter 25 is operated, and the cleaning liquid 101 is circulated between the outer tank 14 and the inner tank 13, and the temperature that moves in the decreasing direction is heated. It is heated by 21 and managed at a constant temperature (step S11). The valve 16 and the valve 31 in the regeneration circulation line 75 are closed.

  As in step S15, when it is necessary to regenerate, the cleaning liquid 101 in the inner tank 13 and the outer tank 14 is cooled by the cooling device 33 and then transferred to the regeneration tank 35 (step S15). The valve 19 in the cleaning circulation line 71 is closed, and the valve 16 and the valve 31 in the regeneration circulation line 75 are opened.

  A little different from step S18, it is kept at about room temperature in the buffer tank 51, and the cleaning liquid 101 is transferred to the inner tank 13 via the preheating device 73 (step S18a). For example, the cleaning liquid 101 is raised to a temperature substantially necessary for the cleaning process.

  A little different from step S19, the valve 16 and the valve 31 are closed and the valve 19 is opened, then the cleaning circulation line 71 is operated, and the heating device 21 raises or adjusts the cleaning liquid 101 (step S19a). .

  As described above, the cleaning system 2 includes the preheating device 73 as compared with the cleaning system 1 of the first embodiment, and the heated cleaning liquid 101 is introduced into the cleaning tank 11. It is unnecessary. Since the regenerated cleaning liquid 101 is raised to a temperature substantially necessary for the cleaning process by the preheating device 73, the time for reaching the predetermined temperature by the cleaning circulation line 71 can be greatly shortened. The rest of the configuration is almost the same, and the cleaning system 2 has the same effects as the cleaning system 1.

  As mentioned above, this invention is not limited to the said Example, In the range which does not deviate from the summary of this invention, it can change and implement variously.

  For example, in the present embodiment, an example in which the cleaning liquid is an SPM cleaning liquid has been described, but a processing liquid having a different composition including water used for other cleaning or the like is also possible. In this case, other processing liquids are used in a circulating manner, and, for example, regeneration processing is performed in a high-temperature heating tank (regeneration tank) having quartz glass at a temperature higher than the processing temperature.

The present invention can be configured as described in the following supplementary notes.
(Additional remark 1) The washing tank which accommodates the washing | cleaning liquid containing a 1st chemical | medical solution and a 2nd chemical | medical solution, and the said heated washing | cleaning liquid are discharged | emitted from the discharge port of the said washing tank, and pass a 1st heating means. The cleaning circulation line that passes through the filtering means and is returned to the inlet of the cleaning tank, and the cleaning liquid is discharged from the outlet of the cleaning tank, passes through the first cooling means, and then heated. The first chemical solution is introduced into an introduction port of the regeneration tank that raises the concentration to a predetermined concentration, is discharged from the discharge port of the regeneration tank, passes through a second cooling means, is stored in the buffer tank, and is stored in the buffer tank. A cleaning system having a regeneration circulation line that passes through a second heating means disposed close to the inlet of the cleaning tank and returned to the inlet of the cleaning tank.

(Additional remark 2) The said buffer tank is a washing | cleaning system of Additional remark 1 maintained at substantially room temperature.

(Additional remark 3) The said 2nd heating means is a washing | cleaning system of Additional remark 1 which has comprised the heating circulation line which has a temperature rising tank, a pump, and a heating apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows typically the washing | cleaning system which concerns on Example 1 of this invention. The flowchart which shows the schematic procedure of the washing | cleaning-liquid circulation method which concerns on Example 1 of this invention. The block diagram which shows typically the washing | cleaning system which concerns on Example 2 of this invention. The block diagram which shows typically the preheating apparatus of the washing | cleaning system which concerns on Example 2 of this invention.

Explanation of symbols

1, 2 Cleaning system 11 Cleaning tank 13 Inner tank 14 Outer tank 16, 19, 23, 27, 31, 83, 85 Valve 17, 53, 81 Pump 21, 79 Heating device 25 Filter 28 Bypass line 29, 71 Cleaning circulation line 33, 41 Cooling device 35 Regeneration tank 51 Buffer tank 55, 75 Regeneration circulation line 73 Preheating device 77 Temperature raising tank 87 Heating circulation line 101 Cleaning liquid

Claims (5)

A cleaning tank containing a cleaning liquid containing the first chemical liquid and the second chemical liquid;
The cleaning liquid is discharged from the outlet of the cleaning tank, passes through the heating means, passes through the filtering means or bypass means that is used by switching, and is returned to the inlet of the cleaning tank, and a cleaning circulation line;
The cleaning liquid is discharged from the outlet of the cleaning tank, and after passing through the first cooling means, is introduced into the inlet of the regeneration tank that raises the concentration of the first chemical liquid to a predetermined concentration by heating, A regeneration circulation line that is discharged from the discharge port of the regeneration tank, passes through the second cooling means, is stored in the buffer tank, and is returned from the buffer tank to the introduction port of the cleaning tank;
A cleaning system comprising: A cleaning tank containing a cleaning liquid containing the first chemical liquid and the second chemical liquid;
The heated cleaning liquid is discharged from the discharge outlet of the cleaning tank, passes through the first heating means, passes through the filtering means, and is returned to the inlet of the cleaning tank; and
The cleaning liquid is discharged from the outlet of the cleaning tank, and after passing through the first cooling means, is introduced into the inlet of the regeneration tank that raises the concentration of the first chemical liquid to a predetermined concentration by heating, The second heating means that is discharged from the discharge port of the regeneration tank, passes through the second cooling means, is stored in the buffer tank, and is disposed close to the inlet of the cleaning tank from the buffer tank. A regeneration circulation line that passes through and is returned to the inlet of the washing tank;
A cleaning system comprising:   The cleaning system according to claim 1 or 2, wherein the first chemical solution is sulfuric acid and the second chemical solution is hydrogen peroxide solution. A step of discharging the cleaning liquid containing the first chemical liquid and the second chemical liquid from the cleaning tank, returning the cleaning liquid to the cleaning tank through the heating means and the filtering means, and performing the cleaning process at a cleaning process temperature higher than room temperature. When,
The cleaning liquid in which the concentration of the first chemical liquid is lowered is cooled by a first cooling means and then transferred to a regeneration tank. In the regeneration tank, the concentration of the first chemical liquid is set to a predetermined concentration at a temperature higher than the cleaning processing temperature. And regenerating the cleaning liquid to a high level,
Cooling the regenerated cleaning liquid with a second cooling means and transferring it to a buffer tank; and transferring the regenerated cleaning liquid from the buffer tank to the cleaning tank;
Discharging the regenerated cleaning liquid from the cleaning tank and circulating it back to the cleaning tank through the heating means and bypass means bypassing the filtering means to raise the cleaning treatment temperature;
A cleaning liquid circulation method characterized by comprising: The cleaning liquid containing the first chemical liquid and the second chemical liquid is discharged from the cleaning tank and circulated back to the cleaning tank through the first heating means and the filtering means, and the cleaning process is performed at a cleaning temperature higher than room temperature. A process of performing
The cleaning liquid in which the concentration of the first chemical liquid is lowered is cooled by a first cooling means and then transferred to a regeneration tank. In the regeneration tank, the concentration of the first chemical liquid is set to a predetermined concentration at a temperature higher than the cleaning processing temperature. And regenerating the cleaning liquid to a high level,
Cooling the regenerated cleaning liquid with a second cooling means and transferring it to a buffer tank; and transferring the regenerated cleaning liquid from the buffer tank to the cleaning tank via a second heating means;
A cleaning liquid circulation method characterized by comprising:

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