JP3654794B2 - Method and apparatus for reusing chemical liquid for surface treatment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a chemical solution for surface treatment in which, when using ultrapure water containing an ion exchange resin as a treatment liquid for surface treatment or cleaning of a substrate, the used treatment liquid is desalted and regenerated by electrodialysis and reused. The present invention relates to a reusing method and apparatus.
[0002]
[Prior art]
The inventors of the present invention firstly in Japanese Patent Application No. 11-52868, a treated surface of a material to be treated is brought into contact with ultrapure water in the presence of an ion exchanger, and an ionic substance eluted from the treated surface is obtained. A surface treatment method for removing with an ion exchanger has been proposed. Since this method does not use chemicals, there is no chemical damage or contamination on the surface, and the eluted ions are adsorbed to the ion exchanger, so the ultrapure water used can be reused almost as it is. .
[0003]
The present invention relates to a method for reusing a processing solution used in the above application. As a method for regenerating the ion exchanger, the cation exchanger is brought into contact with an acid such as hydrochloric acid, the anion exchanger is brought into contact with an alkali such as sodium hydroxide, the cation is subjected to hydrogen ions and the anions. Was regenerated by exchanging with hydroxide ions, and the excess acid / alkali was washed with water.
[0004]
[Problems to be solved by the invention]
If the ion exchanger is a granular resin, it can be easily regenerated by the above method by adopting a packed tower system or the like, but when using a powder resin in consideration of surface treatment efficiency or cleaning efficiency, Since the diameter is small, it can be handled only in the form of a slurry, and there is a problem that it is extremely difficult to separate from the regenerant and the washing water.
Moreover, even if it is a granular resin, the water washing after reproduction | regeneration is performed by dilution by the spreading | diffusion of an acid thru | or alkali, and requires a lot of water.
[0005]
The present invention has been made in view of the above-described circumstances, and solves the problem of difficulty in separation from the regenerant and the washing water in the above-described prior art and the problem that a large amount of water is required for washing after regeneration. It is an object of the present invention to provide a method and an apparatus for reusing a chemical solution for surface treatment.
[0006]
[Means for Solving the Problems]
In the present invention, the used treatment solution is supplied to the deionization chamber of the electrodialyzer as it is for regeneration, or the ion exchange resin is separated from ultrapure water and then regenerated with acid or alkali, and then the electrodialyzer is removed. It is supplied to the ion chamber to remove excess ions.
That is, according to one aspect of the present invention, ultrapure water in which an ion exchange resin is dispersed is used as a treatment liquid for surface treatment or cleaning of a substrate, and the treatment liquid after use is supplied to a deionization chamber of an electrodialyzer. Regeneration is performed by desalting, and the regenerated solution after regeneration is recycled as a processing solution.
In another aspect of the present invention, ultrapure water in which an ion exchange resin is dispersed is used as a treatment liquid for surface treatment or cleaning of a substrate, and the ion exchange resin in the treatment liquid after use is separated. Is an acid, and the anion exchange resin is regenerated with alkali, then supplied to the deionization chamber of the electrodialyzer to remove excess acid or alkali by energization, and the regenerated regenerated solution is recycled and used as a processing solution. It is characterized by this. You may make it supply ultrapure water to the concentration chamber of an electrodialyzer.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a method and apparatus for reusing a chemical for surface treatment according to the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic flow diagram showing one embodiment of a method for reusing a chemical solution for surface treatment according to the present invention. As shown in FIG. 1, a processing liquid made of ultrapure water in which an ion exchange resin is dispersed is accommodated in the cleaning tank 5, and a substrate such as a semiconductor wafer is immersed in the processing liquid and cleaned. And the used liquid 6 after washing | cleaning is supplied to the desalination chamber 1a of the reproduction | regeneration apparatus 1, and is electrically regenerated. The regenerated liquid 2 after regeneration is taken out from the regenerator 1 and stored in the storage tank 3. The regenerated liquid stored in the storage tank 3 is sent to the cleaning tank 5 by the supply pump 4 and used for cleaning the substrate.
[0008]
FIG. 2 is a schematic cross-sectional view showing the configuration of the playback apparatus. As shown in FIG. 2, the regenerator 1 is composed of an electrodialyzer, and a demineralization chamber 1a that constitutes a deionization chamber disposed in the center, and a concentration chamber that is disposed on both sides of the demineralization chamber 1a. A cathode chamber 1e and an anode chamber 1f. A cathode 11 is accommodated in the cathode chamber 1e, and an anode 12 is accommodated in the anode chamber 1f. A DC power supply 13 is connected between the cathode 11 and the anode 12. The desalting chamber 1a and the cathode chamber 1e are partitioned by a cation exchange membrane 1d, and the desalting chamber 1a and the anode chamber 1f are partitioned by an anion exchange membrane 1c. Further, ultrapure water 14 is supplied to the cathode chamber 1e and the anode chamber 1f constituting the concentration chamber.
[0009]
In the above-described configuration, the used liquid 6 is supplied to the desalting chamber 1a of the regenerator 1. The ion exchange resin 2a in the used liquid adsorbs ions by surface treatment or cleaning of the substrate. The ions adsorbed on the ion exchange resin 2a are regenerated by energization in the desalination chamber 1a of the regenerator, the cation moves to the cathode side through the cation exchange membrane 1d, and the anion passes through the anion exchange membrane 1c. To the anode side. Cations and anions are discharged from the regenerator 1 as waste water 8 by the ultrapure water 14 supplied to the cathode chamber 1e and the anode chamber 1f, respectively. The regenerated liquid 2 regenerated in the desalting chamber 1 a is discharged from the desalting chamber 1 a and stored in the storage tank 3.
[0010]
FIG. 3 is a schematic flow diagram showing another embodiment of the present invention. FIG. 4 is a schematic view illustrating the relationship between the resin separation tank / regeneration tank 7 and the regenerator 1.
This embodiment is different from the embodiment shown in FIG. 1 in that a separation tank / regeneration tank 7 is disposed between the cleaning tank 5 and the regenerator 1. Other configurations are the same as those of the apparatus shown in FIG.
[0011]
As shown in FIGS. 3 and 4, the used liquid after washing is put into a separation tank / regeneration tank 7 and separated into ultrapure water and an ion exchange resin. The ultrapure water may be reused as the recycled waste liquid 16 or may be returned to the factory water treatment line. The ion exchange resin after separation is regenerated by the regenerant 17 in the separation tank / regeneration tank 7. In this case, when the ion exchange resin after separation is a cation exchange resin, it is regenerated using an acid as a regenerant, and when the ion exchange resin after separation is an anion exchange resin, an alkali is used as a regenerant. Use to play. After regeneration, the ion exchange resin is supplied to the desalting chamber 1a of the regeneration device 1 and completely regenerated. Regeneration of the ion exchange resin 2a in the regenerator 1 is performed in the same manner as described above, but excess acid or alkali used as a regenerant is removed in the regenerator 1 by energization.
The separation tank / regeneration tank may be one tank or two tanks in which the separation tank and the regeneration tank are separated.
[0012]
【The invention's effect】
As described above, the present invention regenerates the used treatment liquid as it is by supplying it to the deionization chamber of the electrodialyzer, or after separating the ion exchange resin from ultrapure water and regenerating it with acid or alkali, Thereafter, it is supplied to the deionization chamber of the electrodialysis apparatus to remove excess ions. Therefore, it is possible to solve the problems of difficulty in separation from the regenerant and washing water in the prior art and the problem of requiring a large amount of water for washing after regeneration.
[Brief description of the drawings]
FIG. 1 is a schematic flow diagram showing one embodiment of a method for reusing a chemical solution for surface treatment according to the present invention.
FIG. 2 is a schematic cross-sectional view showing the configuration of the playback apparatus shown in FIG.
FIG. 3 is a schematic flow diagram showing another embodiment of the present invention.
4 is a schematic view illustrating the relationship between the separation tank / regeneration tank and the regenerator shown in FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Regenerator 1a Desalination chamber 1c Anion exchange membrane 1d Cation exchange membrane 1e Cathode chamber 1f Anode chamber 2 Regeneration liquid 2a Ion exchange resin 3 Storage tank 4 Supply pump 5 Washing tank 6 Used liquid 7 Separation tank and regeneration tank 8 Waste water 11 Cathode 12 Anode 13 DC power supply 14 Ultrapure water 16 Recycled waste liquid 17 Regenerant

Claims (5)

Uses ultra-pure water with ion-exchange resin dispersed in the surface treatment or cleaning of the substrate as the treatment liquid, and supplies the treatment liquid after use to the deionization chamber of the electrodialysis machine for regeneration and regeneration. A method for reusing a chemical solution for surface treatment, characterized in that a later regenerated solution is circulated and reused as a treatment solution. Ultrapure water with ion exchange resin dispersed in the surface treatment or cleaning of the substrate is used as the treatment liquid, and the ion exchange resin in the treatment liquid after use is separated. The cation exchange resin is acid, and the anion exchange resin. After regenerating with alkali, it is supplied to the deionization chamber of the electrodialyzer and the excess acid or alkali is removed by energization, and the regenerated solution after regeneration is recycled and used as a treatment solution. How to reuse chemicals. The method for reusing a chemical solution for surface treatment according to claim 1 or 2, wherein ultrapure water is supplied to the concentration chamber of the electrodialyzer. An electrodialyzer separated into a deionization chamber, an anode chamber, and a cathode chamber by an anion exchange membrane and a cation exchange membrane; and a DC power source for energizing the anode in the anode chamber and the cathode in the cathode chamber; A treatment solution consisting of ultrapure water in which the ion exchange resin used for treatment or washing is dispersed is supplied to the deionization chamber of the electrodialyzer and regenerated by energization and desalination, and the regenerated solution after regeneration is circulated as a treatment solution. An apparatus for reusing a chemical solution for surface treatment, characterized by being reused. An electrodialyzer separated into a deionization chamber, an anode chamber and a cathode chamber by an anion exchange membrane and a cation exchange membrane, a direct current power source for energizing the anode in the anode chamber and the cathode in the cathode chamber, and a treatment liquid after use A separation tank / regeneration tank for separating and regenerating the ion exchange resin therein, and a treatment liquid comprising ultrapure water in which the ion exchange resin used for surface treatment or cleaning of the substrate is dispersed in the separation tank / regeneration tank The ion exchange resin is separated, and the cation exchange resin is regenerated with acid, and the anion exchange resin is regenerated with alkali, and then supplied to the deionization chamber of the electrodialyzer to remove excess acid or alkali by energization. An apparatus for reusing a chemical solution for surface treatment, characterized by circulating and reusing the regenerated solution as a treatment solution.

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