JPH11190907A - Regenerating method of photoresist developer waste liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy and efficient regenerating method of a developer waste liquid of a photoresist. SOLUTION: In this method to treat a developer waste liquid of a photoresist essentially containing a photoresist and tetraalkyl ammonium (TAA) ion, at least a process to concentrate TAA ion by electrodialysis and/or electrolysis and a process to adsorb and remove impurities by bringing the liquid into contact with an ion exchange resin are carried out. The ion exchange resin is preferably an anion exchange resin and a hydrogen ion type (H-type) and/or TAA ion type (TAA) cation exchange resin. The impurities are residual photoresist, other anion component and cation component such as Na<+> . Thereby, a soln. of tetraalkyl ammonium hydroxide of high purity which can be reused as a photoresist developer is regenerated and recovered from the developer waste liquid of a photoresist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a semiconductor device,
The present invention relates to a photoresist generated in a manufacturing process of an electronic component such as a liquid crystal display (LCD) and a printed circuit board, and a method for regenerating a photoresist developing waste liquid containing tetraalkylammonium ions.

[0002]

2. Description of the Related Art In order to manufacture electronic components such as semiconductor devices, liquid crystal displays, and printed circuit boards, a negative or positive photoresist film is formed on a substrate such as a wafer, and light is transmitted through a pattern mask. Irradiate, then dissolve and develop unnecessary photoresist with developer,
After further processing such as etching, the insoluble photoresist film on the substrate must be removed. Photoresists include a positive type in which exposed portions are soluble and a negative type in which exposed portions are insoluble.Alkaline developers are mainly used as a positive type photoresist developing solution, and as a negative type photoresist developing solution, Organic solvent-based developers are the mainstream, but some use alkali developers.

As the alkali developer, an aqueous solution of tetraalkylammonium hydroxide (tetraalkylammonium hydroxide) is usually used. Therefore, the waste liquid discharged from such a development step (referred to as “photoresist development waste liquid” or “photoresist alkaline development waste liquid”) usually contains dissolved photoresist and tetraalkylammonium ions. Here, as is clear from the above, the tetraalkylammonium ion is usually a hydroxide ion (O
H ⁻ ) is used as a counter ion, but the waste liquid (waste water) differs from factory to factory, and it is not known what gets mixed in, and it may be mixed with other waste water in some cases. Therefore, it may be in the form of a salt having another type of ion as a counter ion. Therefore, in the general description in this specification, a counter ion is not specified, but is captured by the concept of “ion”. However, as described above, the tetraalkylammonium ion in the waste liquid is usually present as tetraalkylammonium hydroxide, and therefore the present invention will be described mainly.

Heretofore, as a method of treating such a photoresist and a photoresist developing waste solution containing a tetraalkylammonium ion, a method of collecting the entire amount by a trader, a method of concentrating by an evaporation method or a reverse osmosis membrane method, and disposing of the waste (incineration or trader collection). ), And a method of biodegrading with activated sludge and discharging. For the concentrated waste liquid obtained as described above or a concentrated waste liquid originally having a high tetraalkylammonium ion concentration, the tetraalkylammonium ion is preferably converted to a hydroxide form (necessary in the electrolytic method) by electrodialysis or electrolysis. Attempts have been made to concentrate, collect, and recycle it.

[0005]

In the method of concentration by the evaporation method or the reverse osmosis membrane method, since the alkali-soluble photoresist and the tetraalkylammonium ion are both concentrated, the waste liquid after the treatment must be disposed of. Absent. In the method of biodegrading with activated sludge, the biodegradability of tetraalkylammonium ions is poor, and when other organic components are mixed in the waste liquid, the growth of microorganisms that degrade the other organic components is promoted. Becomes active and the growth of microorganisms that decompose tetraalkylammonium ions becomes inactive, further deteriorating its biodegradability, so that only low-concentration effluent can be treated, requiring a large-scale treatment facility. . Further, the method of concentrating and recovering tetraalkylammonium ions by electrodialysis or electrolysis, preferably in the form of a hydroxide, is best in terms of pollution control and effective use of resources. High purity is required when reused as a photoresist alkaline developer for the production of electronic components such as liquid crystal displays and printed circuit boards. In this regard, trace amounts of photoresist, Na ⁺ , K ⁺ , Ca ^2+, etc. Cations (especially N
There is a problem that impurities such as a ⁺ ) remain.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned drawbacks of the conventional processing method for a photoresist and a photoresist developing waste solution containing tetraalkylammonium ions, and to provide a simple and effective photoresist developing waste solution. It is to provide a reproduction processing method.

[0007]

SUMMARY OF THE INVENTION The present invention provides a method for treating a photoresist and a photoresist developing waste liquid mainly containing tetraalkylammonium ions.
The step of concentrating tetraalkylammonium ions by electrodialysis and / or electrolysis and the step of adsorbing and removing impurities brought into contact with an ion-exchange resin (anion-exchange resin and / or cation-exchange resin) And, as will be described later, various embodiments can be adopted) .The method includes regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developing solution from a photoresist developing waste solution. Another object of the present invention is to provide a method for regenerating a waste photoresist developing solution.

In the method of the present invention, a photoresist developing waste solution containing a photoresist and a tetraalkylammonium ion (hereinafter sometimes abbreviated as "developing waste solution") is directly concentrated by electrodialysis and / or electrolysis. It is easy to carry out the treatment by the step of adsorbing and removing impurities brought into contact with the ion exchange resin. However, if necessary, prior to these steps, the waste developer or its concentrated solution (evaporation and / or reverse osmosis membrane described later) may be used. The concentrated solution obtained by the treatment is neutralized, and the photoresist is removed to a certain extent by solid-liquid separation to obtain a neutralized solution mainly containing tetraalkylammonium ions in which the amount of the photoresist has been reduced. In some cases, passing through the process is preferable, particularly from the viewpoint of the exchange capacity of the anion exchange resin. However, in this case, an electrolysis step is usually required to convert the tetraalkylammonium ion into a hydroxide (OH) form.

Incidentally, a developing waste solution containing a tetraalkylammonium hydroxide and a photoresist is usually pH 1
The photoresist exhibits an alkalinity of 2 to 14, and the photoresist is dissolved in the alkaline solution. The present invention can be applied to such alkaline developing waste liquid as it is.
Alkali-soluble photoresists have carboxyl groups and the like. At the time of development, these groups are in the form of tetraalkylammonium salts and the photoresist is dissolved in the developing solution. If the pH is adjusted to pH 8 or less (acidic is also acceptable), the photoresist becomes a carboxyl group or the like again and most of the photoresist becomes insoluble, so that most of the photoresist can be removed by a solid-liquid separation method such as centrifugation or filtration. Become. In this specification, a processing solution in which the waste developer and the like are neutralized and the photoresist is removed to some extent by a solid-liquid separation method such as centrifugation or filtration is referred to as a “neutralization processing solution”.

When the photoresist developing waste liquid is first treated by at least one of electrodialysis and electrolysis, a concentrated liquid in which tetraalkylammonium ions (counter ions are mainly hydroxide ions) are concentrated can be recovered. it can. Ion exchange membrane in electrodialysis and electrolysis (However, as described below, in the case of electrodialysis, a neutral membrane can be used instead of the anion exchange membrane, and in the case of electrolysis, instead of the cation exchange membrane, Most of the photoresist remains in the desalting solution ("dilute solution" in which tetraalkylammonium ions are diluted) due to the use of two neutral films, but the concentrated solution recovered A small amount of photoresist remains or is mixed therein. Furthermore, Na ⁺ originally present in the development waste, K ^+, cations Ca ²⁺ and the like (e.g., Na ⁺ is less 10ppb hydroxide in tetramethylammonium product is a developing solution, after use development waste in in some cases there more than 100 ppb) and Cl ^-,
Anions such as NO ₃ ⁻ , SO ₄ ²⁻ , HCO ₃ ⁻ , and CO ₃ ²⁻ move to the concentrated liquid side recovered together with the tetraalkylammonium ion (however, in the case of electrolysis, the movement of the anions is very small. Is). Therefore, the collected tetraalkylammonium ion concentrate contains a small amount of photoresist and ion components as impurities.

When the recovered concentrate is brought into contact with an anion exchange resin, preferably a strongly basic anion exchange resin (preferably in the OH form), the impurities of the photoresist and the anion component are removed. The ionic components remain without being removed. When the anion exchange resin is in the OH form, the tetraalkylammonium ion is advantageously present in the anion exchange treatment concentrated liquid in the form of tetraalkylammonium hydroxide.

Therefore, when the cation component is brought into contact with a cation exchange resin, the cation component is also adsorbed and removed, so that it is sufficiently used as a photoresist alkaline developer for manufacturing electronic components such as semiconductor devices, liquid crystal displays, and printed circuit boards. A highly purified solution of the tetraalkylammonium hydroxide is obtained which can be reused.

Whether the anion exchange resin, the cation exchange resin or both are used as the ion exchange resin depends on the use of the regenerated tetraalkylammonium hydroxide solution in the context of its use. It may be determined according to the allowable amount of various impurities such as photoresist, anions and cations remaining therein. However, for example, as described above, in order to use a regenerated tetraalkylammonium hydroxide solution as a developer for manufacturing electronic components such as semiconductor devices, liquid crystal displays, and printed circuit boards, both anion exchange resin and cation exchange resin are required. It is desirable to use

A method may be employed in which the waste photoresist developing solution is first brought into contact with an ion exchange resin, followed by electrodialysis and / or electrolysis. However, from the viewpoint of the exchange capacity of the anion exchange resin, electrodialysis and / or electrolysis may be carried out first. Alternatively, a method in which electrolysis is performed, and then the resultant is contacted with an ion exchange resin is more preferable.

The anion exchange resin is preferably a fibrous or granular anion exchange resin such as a styrene or acrylic resin in terms of processing efficiency, or a plurality of these may be mixed or laminated at an arbitrary ratio. You may use
As described below, a styrene-based anion exchange resin is particularly preferable in terms of the photoresist removal efficiency. The acrylic anion exchange resin is obtained by crosslinking (meth) acrylic acid or its esters with divinylbenzene (DVB) or the like. In addition, a strong basic anion exchange resin is preferred in terms of photoresist removal efficiency, but a weakly basic anion exchange resin also has a photoresist removal effect, particularly on the neutral or acidic side. May be mixed or laminated at the ratio described above. Further, the counter ion of the anion exchange resin, OH ^- but Cl ^- or the like but, Cl ^-
When an anion exchange resin of a Cl type or the like having a counter ion such as is used, the counter ion of the tetraalkylammonium ion is also changed at least partially to Cl ⁻ or the like, and thus OH ⁻
It is preferable to use an OH type anion exchange resin having a counter ion of Incidentally, and in the case of using a weakly basic anion exchange resin at neutral or acidic side, Cl ^-, etc. The Cl to counterion
When an anion exchange resin in a form or the like is used, in order to convert the tetraalkylammonium ion into a tetraalkylammonium hydroxide form, electrolysis may be performed in a subsequent stage.

The cation exchange resin is preferably a styrene or acrylic cation exchange resin such as fibrous or granular from the viewpoint of processing efficiency. Also, a weakly acidic cation exchange resin may be a strongly acidic cation exchange resin. May be used, or a plurality of these types may be mixed or laminated at an arbitrary ratio.

Cation exchange resins are usually commercially available in hydrogen ion form (H form) or sodium ion form (Na form), and such cation exchange resins (preferably H form) are available.
Is preliminarily used in a tetraalkylammonium form (TAA form), so that tetraalkylammonium hydroxide is adsorbed on the cation exchange resin at the beginning of the passage through the cation exchange resin, It is possible to prevent the occurrence of the phenomenon that the concentration in the processing liquid is reduced. That is, the cation exchange resin can be used as it is in the H form, but is preferably used as the tetraalkyl ammonium form (TAA form). However, instead of the complete TAA-type cation exchange resin, a partially H-type cation exchange resin may be used. Also, the H-type cation exchange resin and the TAA-type cation exchange resin may be mixed or laminated at an arbitrary ratio. May be used.

Ion exchange resin (anion exchange resin and / or
Needless to say, it is preferable to use a cation exchange resin) that has been sufficiently washed with ultrapure water so that there is no eluate at the time of use.

When both the anion exchange resin and the cation exchange resin are used as the ion exchange resin, the mixture is used as a mixed ion exchange resin obtained by mixing the anion exchange resin and the cation exchange resin in a column or a column. However, it is preferable that the anion exchange resin is used by laminating and filling it in a column or a column on the upstream side and the cation exchange resin on the downstream side. However, in the case where the photoresist in the concentrated solution is reduced in a small amount by a multi-stage electrodialysis treatment or the like of the photoresist development waste solution in advance, or when the waste solution originally contains only a small amount of the photoresist, the upstream side is used. A cation exchange resin and an anion exchange resin may be arranged downstream. In addition, an anion exchange resin is filled in an upstream column or column, and a cation exchange resin is packed in a downstream column or column, which can be separately arranged and used.
With a long operation, the exchange capacity is reduced or only the deteriorated ion exchange resin can be easily exchanged, which is convenient. In this case, one of the column or column packed with an anion exchange resin and the column or column packed with a cation exchange resin may be provided before the electrodialysis device and / or the electrolysis device.

The advantage of disposing an anion exchange resin on the upstream side and a cation exchange resin on the downstream side is that a very small amount of amines can be eluted from the anion exchange resin, so that the cation exchange resin is disposed on the downstream side. By disposing the ion exchange resin, the eluting amines can be captured. In addition, since the photoresist which is a polymer substance may be adsorbed on the surface of the cation exchange resin and reduce the activity of the cation exchange, the anion exchange resin is disposed on the upstream side, and the Advantageously, the photoresist is sufficiently removed.

Further, at least before the electrodialysis and / or electrolysis step, the photoresist developing waste liquid or its processing liquid (neutralization processing and / or ion exchange processing liquid) is evaporated and / or evaporated.
Alternatively, it is preferable to further include a step of concentrating by reverse osmosis membrane treatment. When performing the neutralization treatment step and / or the ion exchange treatment step, such a step of the evaporation and / or reverse osmosis membrane treatment may be performed before, after, or between the two steps.

The advantages of performing the evaporation and / or reverse osmosis membrane treatment process include an improvement in current efficiency in electrodialysis and electrolysis, and an electrodialysis device and / or an electrodialysis device associated with a decrease in the amount of liquid to be treated.
Alternatively, reduction in size and running cost of the electrolytic device, reduction in applied voltage, and improvement in the recovery rate of tetraalkylammonium ions can be mentioned.

As described above, during evaporation or reverse osmosis membrane treatment, impurities such as photoresist are also concentrated in the concentrated solution, and these concentrated impurities are at least electrodialyzed and / or electrolyzed (and preferably evaporated and concentrated). There is no particular problem because it is removed by the ion exchange treatment at least at the subsequent stage of the reverse osmosis membrane treatment.

The condensed water of evaporation and the permeated water of the reverse osmosis membrane treatment can be used as process water and the like because they hardly contain photoresist and tetraalkylammonium ions. In the case of the reverse osmosis membrane treatment, it is preferable to perform the treatment at a pH of 9 to 12 from the viewpoint of reducing the deterioration of the reverse osmosis membrane.

When comparing the evaporation with the reverse osmosis membrane treatment, the former has the advantage that the running cost is high but the concentration ratio can be easily increased, and the latter has the advantage that the running cost is low, but the concentration ratio is limited. In order to increase the concentration ratio, a large-scale high-pressure pump is required to overcome the osmotic pressure, and the upper limit of the concentration of tetraalkylammonium ion in a practical concentrated solution is about several percent. Therefore, whether to select evaporation or reverse osmosis membrane treatment or to adopt a combination thereof may be determined from characteristics such as the concentration of tetraalkylammonium ions in the photoresist developing waste liquid.

Further, a membrane processing device may be installed at or near the last stage, in which case fine particles originally present in the developing waste liquid can be removed, and an electrodialysis device and / or an electrolytic device, a pump, an ion exchange device and the like can be used. Even if fine particles are mixed in from a resin or the like, it is preferable because this can be surely removed.

As the above-mentioned film processing apparatus, 0.03-1 μm
A membrane treatment apparatus using a polypropylene (PP) filter or a polytetrafluoroethylene (PTFE) filter having a pore diameter of about m, an ultrafiltration membrane apparatus, and the like can be given. A processing device can be selected and used.

The processing solution obtained as a solution of the high-purity tetraalkylammonium hydroxide thus obtained may be further concentrated by a method such as electrodialysis, electrolysis, evaporation, reverse osmosis or a combination thereof. . In this case, when performing the processing by the above-mentioned film processing apparatus, the order of each processing operation can be any order, but in view of the purpose of the processing by the film processing apparatus is the removal of fine particles, It is preferable to perform the processing by the processing device at the last stage.

Regardless of before and after contact with the ion exchange resin,
When the concentration of the tetraalkylammonium ion is performed by electrodialysis or electrolysis, at least one of the electrodialysis and electrolysis may be performed in a circulation system or a multi-stage system. Can be enhanced.

The tetraalkylammonium ion in the photoresist alkaline developing waste liquid is used as an alkali in a photoresist developing solution used in the production of various electronic parts, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and hydroxide. Tetrapropyl ammonium, tetrabutyl ammonium hydroxide, methyl triethyl ammonium hydroxide, trimethyl ethyl ammonium hydroxide, dimethyl diethyl ammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, triethyl (2-hydroxyethyl) ammonium hydroxide, Dimethyldi (2-hydroxyethyl) ammonium hydroxide, diethyldi (2-hydroxyethyl) ammonium hydroxide, methyltri (2-hydroxyethyl) ammonium hydroxide Um, hydroxide ethyltri (2-hydroxyethyl) ammonium, tetra (2-hydroxyethyl) ammonium and the like (in particular, the former two) derived from tetraalkyl ammonium hydroxide.

The counterions tetraalkylammonium ions in the developing waste solution, hydroxide ions as described above (OH ^-) is in the range of is usually some plants,
When neutralization is performed, fluoride ion, chloride ion, bromide ion, carbonate ion, hydrogen carbonate ion, sulfate ion, hydrogen sulfate ion, nitrate ion, phosphate ion,
Inorganic anions such as hydrogen phosphate ion and dihydrogen phosphate ion,
Generally, at least one selected from organic anions such as formate ion, acetate ion and oxalate ion is at least a part of the counter ion of the tetraalkylammonium ion. In particular, carbonate ions and bicarbonate ions
Carbon dioxide gas in the air often dissolves into the waste developer and is present in a small amount. In the concentrated solution obtained by performing the electrolysis, hydroxide ions are usually counter ions of tetraalkylammonium ions, so that it is difficult to reuse the resulting solution of tetraalkylammonium hydroxide as a photoresist alkaline developer. When the amount of the counter ion other than the hydroxide ion is large enough to cause the above, at least the electrolysis step may be included in the method of the present invention.

In a normal photoresist developing waste solution, the photoresist is dissolved as an anionic polymer due to a carboxyl group or the like, while tetraalkylammonium hydroxide is anionic polymer with tetraalkylammonium ion which is a cation. It is dissociated into hydroxide ions, which are ions.

By bringing such waste liquid into contact with the anion exchange resin, the photoresist in the waste liquid can be adsorbed on the anion exchange resin and removed.

The mainstream of an alkali-developed photoresist is a novolak resin as a base resin, and the novolak resin has a large number of benzene rings. In particular, when using an anion exchange resin having a styrene-based benzene ring as the anion exchange resin, in addition to the electrostatic interaction,
It is considered that the affinity (hydrophobic) interaction between the benzene rings can remove the photoresist with high selectivity.

For this reason, even in a concentrated solution in which the concentration of tetraalkylammonium hydroxide is increased by electrodialysis and / or electrolysis, a large amount of competing hydroxide ions (derived from tetraalkylammonium hydroxide) coexist. Nevertheless, it is believed that the photoresist can be effectively and selectively adsorbed to and removed from the anion exchange resin as described above.

That is, the tetraalkylammonium hydroxide solution (concentrated solution) recovered by electrodialysis and / or electrolysis of the photoresist developing waste solution has a relatively high tetraalkylammonium hydroxide concentration, but has an anion exchange resin. Contacting removes the remaining traces of photoresist (and other anionic impurities), and preferably also contacts cation exchange resin to remove cation impurities, resulting in a processing solution of high purity. It can be recycled and reused as a developer.

Before concentration by electrodialysis and / or electrolysis,
When the photoresist developing waste solution is subjected to contact treatment with the above-described anion exchange resin, the photoresist is easily removed because the tetraalkyl ammonium hydroxide concentration of the developing waste solution is low. Therefore, in this case, the tetraalkylammonium hydroxide solution containing almost no photoresist is concentrated by electrodialysis and / or electrolysis, and is preferably obtained by contacting with a cation exchange resin to remove cation impurities. The processing solution can be regenerated and reused as a high-purity developer.

With respect to the developer waste containing a high concentration of the photoresist, from the viewpoint of the ion exchange capacity of the anion exchange resin, the photoresist is insolubilized by performing a neutralization as a pretreatment, and centrifugation and filtration are performed. After separation and removal by the solid-liquid separation method, it is advantageous to contact the neutralization solution with the anion exchange resin as described above and remove the remaining photoresist by adsorbing the anion exchange resin. By this neutralization, at least a part of the tetraalkylammonium hydroxide becomes a tetraalkylammonium salt.
If the solution containing the tetraalkylammonium salt (neutralization treatment solution) thus obtained is concentrated by electrodialysis or electrolysis,
A high purity tetraalkylammonium salt (for electrodialysis) or tetraalkylammonium hydroxide (for electrolysis) solution can be recovered. In the case of electrolysis as it is, or in the case of electrodialysis, further electrolysis is performed to regenerate it in the form of tetraalkylammonium hydroxide, and desirably it is brought into contact with a cation exchange resin to remove cation impurities. The liquid can be regenerated and reused as a high-purity developer.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention as described above include the following preferred embodiments, but it is to be understood that the present invention is not limited to these embodiments. Needless to say.

A step of treating the photoresist developing waste liquid by at least one of electrodialysis and electrolysis, and a step of treating the concentrated solution mainly containing tetraalkylammonium ions obtained through the above step with an anion exchange resin and H-form and TAA-form concentrates. Contacting at least one cation exchange resin to adsorb and remove impurities, and regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer. A method of regenerating resist developing waste liquid.

Contacting the photoresist developing waste solution with an anion exchange resin and at least one of a cation exchange resin of H type and TAA type to adsorb and remove impurities;
At least one of electrodialysis and electrolysis of the processing solution obtained through the above-mentioned process, and a step of concentrating and separating the solution, a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer. A method of regenerating a waste photoresist developing solution, comprising reclaiming and collecting.

A step of contacting the waste photoresist developing solution with an anion exchange resin to mainly remove and remove impurities of the photoresist; and a step of treating the processing solution obtained through the above step by at least one of electrodialysis and electrolysis. The concentrated liquid mainly containing tetraalkylammonium ions obtained through the step of concentrating and separating and the above two steps is treated with H
Contacting with a cation exchange resin of at least one of a cation exchange resin and a TAA type to further adsorb and remove impurities, thereby regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer. A method for regenerating a photoresist developing waste liquid, the method comprising:

A step of neutralizing the photoresist developing waste liquid to separate and remove the insoluble photoresist, and a step of subjecting the neutralized solution obtained through the above steps to electrodialysis and electrolysis or electrolysis for concentration and separation. And a step of contacting the concentrated solution containing mainly tetraalkylammonium ions obtained through the above two steps with an anion exchange resin and at least one of a cation exchange resin of H form and TAA form to adsorb and remove impurities. Regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer, the method comprising:

A step of neutralizing the photoresist developing waste liquid and separating and removing the insoluble photoresist, and a step of neutralizing the neutralized treatment liquid obtained through the above step with an anion exchange resin and at least one of H-type and TAA-type. Contacting with a cation exchange resin to adsorb and remove impurities;
At least a step of concentrating and separating the processing solution obtained through the step by electrodialysis and electrolysis or by electrolysis, characterized by regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer. A method for regenerating a waste photoresist developing solution.

A step of neutralizing the photoresist developing waste liquid to separate and remove the insoluble photoresist; and contacting the neutralizing treatment liquid obtained through the above step with an anion exchange resin to mainly remove residual photoresist impurities. Adsorbing and removing, a step of concentrating and separating the treatment liquid obtained through the above two steps by electrodialysis and electrolysis or by electrolysis, and a concentrated liquid mainly containing tetraalkylammonium ions obtained through the above three steps. H type and TAA
Contacting with at least one cation exchange resin in the form to further remove impurities by adsorption, and regenerate and recover a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developer. A method for regenerating a waste photoresist developing solution.

As described above, in the above methods (1) to (4), it is desirable to carry out the film treatment at or near the last stage. In the above methods (1) to (4), at least before the electrodialysis and / or electrolysis step, the photoresist developing waste liquid or a processing liquid thereof (neutralization processing and / or ion exchange processing liquid) is subjected to evaporation and / or reverse osmosis membrane processing. As described above, the method preferably further includes a step of concentrating by heating. Next, an example of a preferable order (flow) of a series of unit operations in this case will be described, but the present invention is not limited thereto. In each of the following examples, the display of (film processing) indicates that it is desirable to perform film processing, but this indicates that this is not an essential unit operation.

(1) Evaporation / reverse osmosis membrane treatment → electrodialysis / electrolysis → ion exchange treatment (anion exchange resin + cation exchange resin mixed bed, hereinafter simply referred to as “mixed bed”) → (membrane treatment) ( 2) Evaporation / reverse osmosis membrane treatment → electrodialysis / electrolysis → anion exchange treatment → cation exchange treatment → (membrane treatment)

(3) Neutralization treatment (neutralization + solid-liquid separation, the same applies hereinafter) → evaporation / reverse osmosis membrane treatment → electrolysis → ion exchange treatment (mixed bed) → (membrane treatment) (4) Neutralization treatment → evaporation / Reverse osmosis membrane treatment → electrolysis → cation exchange treatment → (membrane treatment) (5) Neutralization treatment → evaporation / reverse osmosis membrane treatment → electrolysis → anion exchange treatment → cation exchange treatment → (membrane treatment)

(6) Anion exchange treatment → evaporation / reverse osmosis membrane treatment → electrodialysis / electrolysis → ion exchange treatment (mixed bed) → (membrane treatment) (7) anion exchange treatment → evaporation / reverse osmosis membrane treatment → Electrodialysis / electrolysis → cation exchange treatment → (membrane treatment) (8) anion exchange treatment → evaporation / reverse osmosis membrane treatment → electrodialysis / electrolysis → anion exchange treatment → cation exchange treatment → (membrane treatment)

(9) Evaporation / reverse osmosis membrane treatment → anion exchange treatment → electrodialysis / electrolysis → ion exchange treatment (mixed bed) → (membrane treatment) (10) Evaporation / reverse osmosis membrane treatment → anion exchange treatment → Electrodialysis / electrolysis → cation exchange treatment → (membrane treatment) (11) Evaporation / reverse osmosis membrane treatment → anion exchange treatment → electrodialysis / electrolysis → anion exchange resin → cation exchange treatment →
(Film treatment)

(12) Neutralization treatment → anion exchange treatment → evaporation / reverse osmosis membrane treatment → electrolysis → ion exchange treatment (mixed bed) →
(Membrane treatment) (13) Neutralization treatment → Anion exchange treatment → Evaporation / reverse osmosis membrane treatment → Electrolysis → Cation exchange treatment → (Membrane treatment) (14) Neutralization treatment → Anion exchange treatment → Evaporation / reverse osmosis Membrane treatment → electrolysis → anion exchange treatment → cation exchange treatment →
(Film treatment)

(15) Neutralization treatment → Evaporation / reverse osmosis membrane treatment →
Anion exchange treatment → electrolysis → ion exchange treatment (mixed bed) →
(Membrane treatment) (16) Neutralization treatment → Evaporation / reverse osmosis membrane treatment → Anion exchange treatment → Electrolysis → Cation exchange treatment → (Membrane treatment) (17) Neutralization treatment → Evaporation / reverse osmosis membrane treatment → Anion Exchange treatment → electrolysis → anion exchange treatment → cation exchange treatment →
(Film treatment)

(18) Evaporation / reverse osmosis membrane treatment → neutralization treatment →
Anion exchange treatment → electrolysis → ion exchange treatment (mixed bed) →
(Membrane treatment) (19) Evaporation / reverse osmosis membrane treatment → neutralization treatment → anion exchange treatment → electrolysis → cation exchange treatment → (membrane treatment) (20) Evaporation / reverse osmosis membrane treatment → neutralization treatment → anion Exchange treatment → electrolysis → anion exchange treatment → cation exchange treatment →
(Membrane treatment) (21) Evaporation / reverse osmosis membrane treatment → neutralization treatment → electrolysis → ion exchange treatment (mixed bed) → (membrane treatment) (22) Evaporation / reverse osmosis membrane treatment → neutralization treatment → electrolysis → anion Exchange treatment → cation exchange treatment → (membrane treatment)

An example in which the waste developer is regenerated according to the embodiment of the present invention using the electrodialysis method and reused as a developer for a photoresist for manufacturing electronic components will be described more specifically. As a photoresist developer, most commonly, tetramethylammonium hydroxide (hereinafter referred to as "TM
AH) is used as an aqueous solution having a concentration of 2.38% by weight. When the photoresist is developed with this developer, a developing waste liquid containing the photoresist and TMAH is usually generated.
The development waste liquid or its processing liquid or the concentrated liquid obtained by evaporation or reverse osmosis membrane treatment is concentrated by electrodialysis, and TMAH
A concentrate is obtained. The concentrated solution is brought into contact with an anion exchange resin to remove the photoresist remaining in the concentrated solution by adsorbing the anion exchange resin, and, if necessary, the treatment solution is further concentrated by electrodialysis (and / or electrolysis). . In this case, the development waste liquid becomes N
a ⁺ , K ⁺ , Ca ²⁺ , Fe ²⁺ , Fe ³⁺ , Cu ²⁺ , Al ³⁺
And the like are usually contained, and these metal ions are not removed by electrodialysis but rather concentrated. Therefore, when the obtained concentrated solution is used as it is as a regenerating developer, these metal ions may adversely affect the production of electronic components. Therefore, H type and TAA type (in this case, TMA
) Is treated with at least one cation exchange resin.

In this embodiment, electrodialysis is performed with TMA.
Instead of concentrating to an aqueous solution having a H concentration of 2.38% by weight, for example, it is concentrated to an aqueous solution having a TMAH concentration of about 1% by weight, and this is concentrated with a commercially available concentrated aqueous solution having a TMAH concentration of about 20% by weight. Adjusting the concentration to 38% by weight and reusing it as a photoresist developer is advantageous because the concentration of impurities such as metal ions as described above can sometimes be further reduced. Conversely, when a concentrated solution obtained by pretreatment such as evaporation or reverse osmosis membrane treatment is used, a recovered developer having a TMAH concentration exceeding 2.38% by weight can be easily obtained. When used as a regenerating developer after dilution, the concentration of impurities such as metal ions as described above can be further reduced in some cases, which is advantageous.

Next, the principle of electrodialysis when electrodialysis is performed in the method for treating a developing waste solution of the present invention will be described with reference to FIG. The counter ion of the tetraalkylammonium ion (hereinafter abbreviated as “TAA ion”) is a hydroxide ion (OH ⁻ , hereinafter abbreviated as “OH ion”), and tetraalkylammonium hydroxide (hereinafter, abbreviated as “OH ion”).
The normal case in the form of “TAAH” will be described.

As shown in FIG. 1, a cation exchange membrane (cation exchange membrane) 3 and an anion exchange membrane (anion exchange membrane) 4 are alternately arranged between the cathode 1 and the anode 2 to form a plurality of cells. Is composed. The TAAH in the raw waste liquid (development waste liquid, evaporation and / or treatment liquid obtained through reverse osmosis membrane treatment and / or ion exchange resin treatment) containing the TAAH and the photoresist sent to the cell is TAA as a cation.
When a direct current is applied between the cathode 1 and the anode 2, the TAA ions move to the cathode side through the cation exchange membrane 3 because they are dissociated into ions (TAA ⁺ ) and OH ions as anions. The OH ions are almost blocked by the next anion exchange membrane 4, while the OH ions move to the anode side through the anion exchange membrane 4, but are almost blocked by the next cation exchange membrane. The cells that are enriched and adjacent to the cell will have reduced TAAH. That is, the cell (A) having the anion exchange membrane 4 on the side facing the cathode 1 functions as a concentration cell, in which the TAAH is concentrated to become a concentrated solution, and the side on which the anion exchange membrane 4 faces the anode 2 (B) function as a desalination cell, and here TAAH
Decreases to become a desalinated solution. Since the photoresist in the raw waste liquid hardly passes through the ion exchange membrane, it passes through the concentration cell and the desalination cell as it is, and remains in the concentrated liquid and the desalted liquid.

As is clear from the above description, when the raw waste liquid is passed through both the desalination cell and the concentration cell as shown in FIG. 1, the photoresist remains in the concentrate as it is. However, since only the TAAH is concentrated on the concentration cell side and the photoresist is not concentrated,
The concentration of the photoresist in the concentrated solution is almost the same as the concentration in the raw waste liquid. In this respect, the electrodialysis method is clearly different from the evaporation method and the reverse osmosis method in which not only the TAAH but also the photoresist is concentrated at the same time. I do.

Since the object of the present invention is to regenerate and recover a high-purity TAAH solution which can be reused as a photoresist alkaline developer, it is preferable to obtain a concentrated solution containing almost no photoresist by electrodialysis. For this purpose, the raw waste liquid is passed through the desalination cell side, and the (super) pure water or low-concentration T containing no photoresist is passed through the concentration cell side.
It is preferable to pass an electrolyte solution such as an AAH solution (for example, a solution obtained by dissolving a small amount of new TAAH in (ultra) pure water). However, when the raw waste liquid is also sent to the concentration cell, it is advantageous in that the amount (volume) of the wastewater discharged as the desalted liquid is reduced.

As the electrodialysis device, a commonly used device can be used, and the ion exchange membrane used for the device is not particularly limited as long as it can selectively separate cations and anions. For example, Aciplex (manufactured by Asahi Kasei Kogyo Co., Ltd.), Selemion (manufactured by Asahi Glass Co., Ltd.), Neosepta (manufactured by Tokuyama Soda Co., Ltd.) and the like can be mentioned.
In addition, the characteristics of the ion exchange membrane may be general ones. For example, the thickness is 0.1 to 0.6 mm, and the resistance is 1 to 10 mm.
It may be about Ω · cm ² .

The structure of the electrodialysis device is not particularly limited.
For example, the cation exchange membrane and the anion exchange membrane are alternately maintained at appropriate intervals by a gasket provided with an inlet and an outlet for the liquid to be desalted and an inlet and an outlet for the liquid to be concentrated. A plurality of cells may be formed by laminating a plurality of cells, and an electrodialysis apparatus may be formed by sandwiching both ends between a pair of electrodes.

Here, instead of the anion exchange membrane, a neutral membrane such as a polyvinyl alcohol-based membrane having better alkali resistance than the anion exchange membrane may be used. The neutral membrane is a mere polymer membrane without ionic functional groups. Although it passes through TAA ions, its permeability is lower than that of cation exchange membranes. Can be concentrated by electrodialysis. However, when a neutral membrane is used instead of the anion exchange membrane, the current efficiency is lower than in the case of the anion exchange membrane.

Examples of the electrodialysis process include a circulation system as shown in FIG. 2 and a multi-stage processing system as shown in FIG.

In the circulation system shown in FIG. 2, the raw waste liquid from the waste liquid tank 6 containing the raw waste liquid containing TAAH and the photoresist is sent to the desalting liquid tank 7 by the pump 9, and the raw waste liquid is pumped from the desalting liquid tank 7 by the pump 10. The direct current is applied to the desalting cell of the electrodialysis apparatus 5 and the desalted liquid flowing out of the desalting cell is returned to the desalting liquid tank 7 and circulated. On the other hand, the concentrated liquid tank 8 contains raw waste liquid,
Alternatively, a (super) pure water or a low-concentration TAAH solution containing no photoresist [for example, a (new) TAA in (ultra) pure water
An electrolyte solution such as a solution in which a small amount of H is dissolved] is fed into the concentration cell of the electrodialyzer 5 by the pump 11, and the concentrated liquid flowing out of the concentrated cell is returned to the concentrated liquid tank 8 and circulated. The electric conductivity of the desalinated liquid in the desalted liquid tank 7 is measured by an electric conductivity meter 1.
When the desalting reaches a certain desalting rate after the measurement in step 2, a part of the desalting solution in the desalting solution tank 7 is discharged to the outside of the tank, and the waste liquid is discharged into the desalting solution tank 7 by the discharged amount. The raw waste liquid is sent from the tank 6. On the other hand, when the TAAH concentration in the concentrate tank 8 reaches a predetermined concentration, the concentrate is taken out of the concentrate tank 8. The removed concentrate is sent to a contact step with an ion exchange resin, a membrane treatment step, reuse, or the like.

In the multi-stage processing system shown in FIG.
The desalted liquid obtained by electrodialyzing the raw waste liquid sent from the pump 15 by the first electrodialysis device 13-1 is transported to the second electrodialysis device 13-2 by the pump 16 for electrodialysis. ,
The TAAH remaining in the desalted solution is concentrated and recovered. The concentrated solution that has been electrodialyzed by the second electrodialysis device 13-2 and the TAAH has been concentrated is electrodialyzed by the first electrodialysis device 13-1 together with the concentrated solution transported by the pump 17, and is subjected to the third electrodialysis. By electrodialysis with the device 13-3, the TA
AH is further concentrated to a higher concentration. Third electrodialysis device 13
The concentrated solution electrodialyzed in -3 is sent to a contact step with an ion exchange resin, a membrane treatment step, reuse, etc., and the desalted solution treated in the third electrodialysis device 13-3 is pumped by a pump 18. Second
Is returned to the electrodialysis apparatus 13-2, and the remaining TAAH is concentrated and recovered by electrodialysis with the desalted solution obtained in the first electrodialysis apparatus 13-1. Most of the desalted solution flowing out of the second electrodialysis device 13-2 is a photoresist and is discharged out of the system because the TAAH concentration is low.

Although not shown in FIG. 3, (Ultra) pure water or a low-concentration TAAH solution containing no photoresist [for example, on the concentration cell side of the first electrodialysis apparatus 13-1]
(A solution in which a small amount of new TAAH is dissolved in (ultra) pure water] may be passed, and a concentrated solution with higher purity can be obtained. However, in the system of both FIGS. 2 and 3, when the raw waste liquid is also sent to the concentration cell, it is advantageous in that the amount (volume) of the wastewater discharged as the desalted liquid is reduced.

Next, with reference to FIG. 4, the principle of electrolysis when electrolysis is performed in the method for treating a developing waste solution of the present invention will be described. Note that a description will be given of a normal case where the counter ion of the TAA ion is an OH ion and is in the form of TAAH.

As shown in FIG. 4, the cathode 21 and the anode 22
A cation exchange membrane 23 is disposed between the two to constitute a cathode cell (C) and an anode cell (D). The cation exchange membrane theoretically allows only cations to pass (actually, it also slightly passes anions and the like). A raw waste liquid (development waste liquid, a processing liquid obtained through ion exchange resin processing, or a concentrated liquid obtained through evaporation or reverse osmosis membrane processing) is passed through the anode cell (D), and is passed through the cathode cell (C). An electrolyte solution such as (ultra) pure water or a low-concentration TAAH solution not containing a photoresist (for example, a solution obtained by dissolving a small amount of new TAAH in (ultra) pure water) is passed. TAAH in raw effluent is TAA ion (TAA ion).
A ⁺⁾ and OH ions (OH ^- Since the dissociated), by applying a direct current between the cathode 21 and anode 22, TAA
Since the ions are cations, they move to the cathode (-) side and enter the cathode cell (C) through the cation exchange membrane 23. Cathode 2
On 1, hydrogen ions (H ⁺ ) of water (H ₂ O ← → H ⁺ + OH ⁻ ) receive electrons (e ⁻ ) and hydrogen gas (H ₂ )
The resulting, is the remaining anion OH ions (OH ^-)
Is the T which has entered the cathode cell (C) from the anode cell (D).
It becomes a counter ion of AA ion and generates TAAH. Therefore, as the electrolysis proceeds, TAAH is concentrated in the cathode cell (C). In this sense, the cathode cell (C) functions as a concentration cell. On the other hand, on the anode 22, TA
AH of OH ions (OH ^-) e ^- release, (e)
It becomes oxygen gas (O ₂ ) and water. In this sense, the anode cell (D) functions as a desalination cell and produces a desalted solution ("dilute solution" in which the TAA ions are diluted).

[0069] It should be noted, Cl in the original waste ^- and Br ^- such as OH
^- electrolyzed easily ion species is contained than the C
Gases such as l ₂ and Br ₂ are generated. In this case, Japanese Patent Application Laid-Open
As disclosed in JP-A-155390, if an anode cell is further divided by an anion exchange membrane and an alkali substance such as ammonium hydroxide is added to the anode-side division cell,
By the neutralization, generation of a gas such as Cl ₂ or Br ₂ can be prevented. Since hard than is electrolyzed, OH ^{- -} in the case of OH ^- SO ₄ ^2- and NO ₃ it is to O ₂ is generated electrolysis,
H ₂ SO ₄ and HNO ₃ remain.

Also, instead of using a cation exchange membrane,
An anode chamber, an intermediate chamber, and a cathode chamber are provided using a neutral membrane such as a porous Teflon membrane that has been subjected to hydrophilization treatment, and electrolysis can also be performed by passing raw waste liquid into the intermediate chamber (Japanese Patent Laid-Open No. 60-24 / 1985).
7641).

When it is desired to obtain a TAAH concentrated solution having a higher purity, a plurality of cation exchange membranes (preferably two) are arranged between the cathode and the anode, and the raw waste liquid is placed in the cell on the anode side (anode cell). Then, the cell on the cathode side (cathode cell) and the intermediate cell are supplied with (ultra) pure water or a low-concentration TAAH solution containing no photoresist [for example, a small amount of new TAAH is dissolved in (ultra) pure water. When the electrolyte solution is passed through, the TAAH is purified in multiple stages, and a high-purity TAAH concentrated solution is obtained from the cathode cell.

The configuration used in the electrodialysis system shown in FIGS. 2 and 3 can be applied to electrolysis as it is.

Here, the terms “concentrate” and “desalted solution” are terms used depending on whether the TAAH content increases or decreases, and do not indicate which TAAH concentration is higher or lower. There is no.

[0074]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples, but it goes without saying that the present invention is not limited to these Examples.

Example 1 A photoresist discharged from a liquid crystal display manufacturing process and a photoresist developing waste liquid containing tetramethylammonium hydroxide (TMAH) were used. The waste water had a TMAH concentration of 15000 ppm, a photoresist-derived TOC concentration of 280 ppm, and a pH of 12.2.
8. The sodium concentration was 130 ppb. Note that T
The MAH concentration was measured by ion chromatography, the photoresist concentration was measured by absorption spectroscopy, and the sodium concentration was measured by atomic absorption spectroscopy.

Using the developing waste liquid as a sample liquid, TMAH was separated, concentrated, and recovered in ultrapure water by an electrodialysis apparatus in a circulating manner. Asahi Kasei Kogyo Co., Ltd.
And a cation exchange membrane Aciplex K-501 (manufactured by Asahi Kasei Kogyo Co., Ltd.) and an anion exchange membrane Aciplex A-2.
01 [made by Asahi Kasei Corporation] was used. Here, other materials may be used as the ion exchange membrane,
Aciplex PVA # 10 instead of anion exchange membrane
0 [manufactured by Asahi Kasei Corporation] may be used.

At a voltage of 12 V, the TMAH concentration of the recovered liquid was 3
When electrodialysis was performed until the concentration reached 0000 ppm (30 g / l), the concentration of TOC derived from the photoresist in the obtained recovered solution was 12 ppm, the pH was 13.4, and the sodium concentration was 290 ppb.

Next, a column packed with a strongly basic anion exchange resin Amberlite IRA-402BL (manufactured by Rohm and Haas Co., Ltd., OH type) was prepared, and the recovered liquid was passed. The TMAH concentration of the processing solution is 30,000 ppm, the TOC concentration derived from the photoresist is 0.1 ppm or less, p
H was 13.5 and sodium concentration was 300 ppb.

Further, a column was prepared in which a strongly acidic cation exchange resin Amberlite 200C (manufactured by Rohm and Haas Co.) was previously filled with a tetramethylammonium form (TMA form). did. The TMAH concentration of the obtained processing solution is 30,000 ppm, the TOC concentration derived from the photoresist is 0.1 ppm or less,
Was 13.5 and the sodium concentration was 10 ppb or less.

Example 2 The TMAH concentration of the recovered liquid was 2.4 at a TMAH recovery rate of 80%.
Electrodialysis was performed until the weight of the solution reached a weight percent, and the strongly basic anion exchange resin Amberlite IRA-900 (manufactured by Rohm and Haas Co., Ltd., OH type) and the strongly acidic cation exchange resin Amberlite 200C (Rohm and Haas) were used. The following sample liquids were treated in the same manner as in Example 1 except that a column packed with a mixed bed was used.

<Sample liquid> (1) Sample liquid 1: Company A developer waste liquid (2) Sample liquid 2: Concentrated liquid obtained by evaporating Company A developer waste liquid (residual liquid) (3) Sample liquid 3: Company B Development waste liquid (4) Sample liquid 4: Concentrate obtained by subjecting Company B development waste liquid to reverse osmosis membrane treatment

Table 1 shows the current efficiency of each of these sample solutions in electrodialysis. FIG. 5 is a graph showing the relationship between the TMAH concentration and the current efficiency by plotting the data of Table 1.

[0083]

[Table 1] 液 Sample solution TMAH (% by weight) Current efficiency (%)試 料 Sample liquid 1 0.4 78 Sample liquid 2 29 98 Sample liquid 30 0.891 sample liquid 4 2.5 96 ──────────────────────────────────

For each of these sample solutions, the TMAH
Concentration, TOC concentration derived from photoresist, and sodium concentration, as well as the TMAH concentration of the concentrated liquid (recovered liquid) obtained by electrodialysis and the processing liquid (purified liquid) obtained by further ion-exchange treatment, and the TOC concentration derived from photoresist And the sodium concentration are shown in Table 2. In Table 2, "photoresist" represents the TOC concentration derived from the photoresist.

[0085]

[Table 2] ＴＭ TMAH photoresist sodium (wt%) (ppm) ( ppb) 試 料 Sample liquid 1 0.4 40 20 Recovered liquid 2.4 10 180 Purified liquid 2.4 0.1 <10 ° Sample liquid 2 29 3000 1600 Recovered liquid 2.4 8 420 Purified liquid 2.4 0.1 <10 ° ── Sample liquid 3 0.8 170 50 Recovered liquid 2.4 13 210 Purified liquid 2.4 0.1 <10─────────────────────── ─────────── Sample liquid 4 2.5 580 150 Recovered liquid 2.4 10 220 Purified liquid 2.4 0.1 <10 ° ───

Sample liquid 1 and sample liquid 2 (concentrated liquid by evaporation)
In comparison, the sample liquid 2 has a higher current efficiency of electrodialysis and a higher processing speed, a higher recovery liquid / sample liquid volume ratio,
There is no difference in impurity concentration when compared with the purified liquid. Also in the comparison between the sample liquid 3 and the sample liquid 4 (concentrated liquid by reverse osmosis membrane treatment), the sample liquid 4 has a higher current efficiency of electrodialysis and a higher processing speed, a higher recovery liquid / sample liquid volume ratio, and a higher purification. There is no difference in impurity concentration when compared with liquids.

When the concentrated solution of the developing waste solution obtained by evaporation or reverse osmosis membrane treatment is subjected to electrodialysis, the amount of impurities in the recovered solution (concentrated solution) is not much different from that when the developing waste solution is directly electrodialyzed. There is no significant difference in the ion exchange resin processing cost. Regarding the cost of electrodialysis treatment, the case where the above concentrated solution is electrodialyzed is much lower than the case where the developing waste solution is directly electrodialyzed.

Further, the TMAH concentration of the desalted solution of the sample solution 1 at a TMAH recovery rate of 80% was 0.08% by weight, whereas the TMAH concentration of the desalted solution of the sample solution 2 was 5.8% by weight.
Therefore, the desalted solution of the sample solution 2 is further subjected to electrodialysis, and T
The MAH recovery rate can be increased to 95% or more, and at this time, the TMAH concentration of the desalted solution becomes 1.45% or less. On the other hand, it is practically impossible to secure a TMAH recovery of 95% from the sample solution 1 (at this time, the TMAH concentration of the desalted solution was calculated to be 0.02% by weight, and a low TMAH close to this was calculated.
At a concentration, the movement of ions becomes extremely slow.)

When TMAH is separated, concentrated and recovered in ultrapure water by electrodialysis as in this example, the desalted solution is produced in substantially the same amount as the sample solution. When the concentration is performed as a pretreatment, the amount of the desalted solution is inevitably reduced, and the cost of disposal of the desalted solution, biological treatment, and the like can be reduced.

The desalted solution may be concentrated again by evaporation or reverse osmosis membrane treatment, and the concentrated solution may be subjected to a treatment such as electrodialysis.
If impurities such as photoresist are concentrated to a high concentration, it is possible that operation such as electrodialysis may be hindered (deposition of photoresist, deterioration of electrodialysis concentrated water quality, etc.). Then, the disposal method of the desalted liquid (reprocessing or disposal) may be determined.

In any case, the total processing cost can be reduced by incorporating a concentration step by evaporation or reverse osmosis membrane treatment.

[0092]

According to the method for regenerating a photoresist developing waste solution of the present invention, a photoresist developing waste solution containing at least a tetraalkylammonium ion containing a photoresist is subjected to an electrodialysis and / or electrolysis step and an ion exchange resin (preferably, an ion exchange resin). , Anion exchange resin and H form and TA
By performing at least the step of contacting with at least one of the A-type cation exchange resin), impurities such as a photoresist and other ionic components can be sufficiently removed, and the photoresist can be reused as an alkaline developer. A solution containing tetraalkylammonium hydroxide having a high purity can be obtained.

By performing an evaporation and / or reverse osmosis membrane treatment step at least before the electrodialysis and / or electrolysis step, the current efficiency in electrodialysis and electrolysis is improved, and the electrodialysis apparatus and Advantages such as miniaturization of the electrolysis apparatus, reduction of running cost, reduction of applied voltage, and improvement of the recovery rate of tetraalkylammonium ion, and the like, can reduce the total processing cost.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of electrodialysis when electrodialysis is performed in the method of the present invention.

FIG. 2 is a flow chart illustrating an example of a process for performing electrodialysis in a cyclic manner.

FIG. 3 is a flowchart for explaining an example of a process for performing electrodialysis in a multi-stage processing method.

FIG. 4 is a diagram illustrating the principle of electrolysis when electrolysis is performed in the method of the present invention.

FIG. 5 is a graph showing the relationship between the concentration of tetramethylammonium hydroxide in the water to be treated and the current efficiency in electrodialysis.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cathode 2 Anode 3 Cation exchange membrane (cation exchange membrane) 4 Anion exchange membrane (anion exchange membrane) 5 Electrodialyzer 6 Waste liquid tank 7 Demineralized liquid tank 8 Concentrated liquid tank 9, 10, 11 Pump 12 Electric conductivity Total 13-1 First electrodialysis device 13-2 Second electrodialysis device 13-3 Third electrodialysis device 14 Waste tank 15, 16, 17, 18 Pump 21 Cathode 22 Anode 23 Cation exchange membrane

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/32 C02F 1/46 103

Claims (16)

[Claims] 1. A method for treating a photoresist developing waste solution mainly containing a photoresist and a tetraalkylammonium ion, comprising the steps of treating the photoresist developing wastewater by at least one of electrodialysis and electrolysis to concentrate the tetraalkylammonium ion. Photoresist development characterized by regenerating and recovering a high-purity tetraalkylammonium hydroxide solution that can be reused as a photoresist developing solution from a photoresist developing waste solution, including at least a step of adsorbing and removing impurities brought into contact with the resin. Waste liquid regeneration treatment method. 2. The method according to claim 1, wherein the ion exchange resin is an anion exchange resin and / or a cation exchange resin of at least one of a hydrogen ion form (H form) and a tetraalkylammonium ion form (TAA form). A method for regenerating a photoresist developing waste liquid according to claim 1. 3. A step of treating the photoresist developing waste liquid by at least one of electrodialysis and electrolysis, and converting the concentrated liquid mainly containing tetraalkylammonium ions obtained through the step to an anion exchange resin and H-form. 3. The method according to claim 1, further comprising a step of contacting at least one cation exchange resin of a TAA type to adsorb and remove impurities. 4. A step of contacting the photoresist developing waste liquid with an anion exchange resin and at least one of an H type and a TAA type cation exchange resin to adsorb and remove impurities, and treating the processing liquid obtained through the step. 3. The method according to claim 1, further comprising a step of performing concentration and separation by at least one of electrodialysis and electrolysis. 5. A step of bringing said photoresist developing waste solution into contact with an anion exchange resin to mainly adsorb and remove impurities in the photoresist, and a treatment solution obtained through said step is subjected to at least one of electrodialysis and electrolysis. A step of treating and concentrating and separating, and a concentrated solution mainly containing tetraalkylammonium ions obtained through the above two steps is brought into contact with at least one of a cation exchange resin of H form and TAA form to further adsorb and remove impurities. 3. The method according to claim 1, further comprising the steps of: 6. Neutralizing the photoresist developing waste liquid,
A step of separating and removing the insoluble photoresist,
A step of subjecting the neutralized solution obtained through the above steps to a treatment by electrodialysis and electrolysis or by electrolysis to concentrate and separate, and an anion exchange resin containing a concentrated solution mainly containing tetraalkylammonium ions obtained through the above two steps. And H
3. A method for regenerating a photoresist developing waste solution according to claim 1, further comprising a step of contacting with at least one of a cation exchange resin of a type and a TAA type to adsorb and remove impurities. 7. Neutralizing the photoresist developing waste liquid,
A step of separating and removing the insoluble photoresist,
A step of contacting the neutralization solution obtained through the above steps with an anion exchange resin and at least one of a cation exchange resin of H type and TAA type to adsorb and remove impurities, and a treatment obtained through the above two steps 3. The method according to claim 1, further comprising a step of concentrating and separating the solution by electrodialysis and electrolysis or by electrolysis. 8. The photoresist developing waste liquid is neutralized,
A step of separating and removing the insoluble photoresist,
Contacting the neutralization treatment solution obtained through the above process with an anion exchange resin to mainly adsorb and remove residual photoresist impurities, and subjecting the treatment solution obtained through the above two processes to electrodialysis and electrolysis or electrolysis. And the concentrated liquid mainly containing tetraalkylammonium ions obtained through the above three steps is subjected to H-form and TA
3. The method according to claim 1, further comprising a step of contacting at least one type A cation exchange resin to further adsorb and remove impurities. 9. A step of evaporating and / or reverse osmosis-treating the photoresist developing waste solution or a processing solution thereof (or a neutralizing solution thereof) at least before the electrodialysis and / or electrolysis step. 9. The method according to claim 1, further comprising the step of: 10. The photoresist development according to claim 2, wherein the anion exchange resin and the cation exchange resin are used as a mixed ion exchange resin. Waste liquid regeneration treatment method. 11. The laminated ion exchange resin according to claim 2, wherein said anion exchange resin is used on the upstream side and said cation exchange resin is used on the downstream side.
10. The method for regenerating a photoresist developing waste liquid according to any one of 6, 7, and 9. 12. The anion exchange resin layer (column,
10. The method according to claim 2, wherein a tower is disposed upstream of the cation exchange resin layer (column, tower). 13. The anion exchange resin according to claim 2, wherein the anion exchange resin is a hydroxide ion form (OH form, that is, a hydroxide form) strongly basic anion exchange resin.
3. The method for regenerating a photoresist developing waste liquid according to any one of 2. 14. The cation exchange resin according to claim 2, wherein the cation exchange resin is a TAA type cation exchange resin.
4. The method for reclaiming a photoresist developing waste liquid according to any one of the above items 3. 15. The method according to claim 1, wherein at least one selected from electrodialysis and electrolysis is performed by a circulation system or a multi-stage system. 16. The method according to claim 1, wherein a film processing apparatus is disposed at or near the terminal to remove fine particles from the high-purity tetraalkylammonium hydroxide solution.
5. The method for regenerating a photoresist developing waste liquid according to any one of the above items 5.