阅读说明：本技术 从回收抗蚀剂剥离剂回收二甲基亚砜的方法 (Method for recovering dimethyl sulfoxide from recovered resist stripping agent ) 是由 马屋原邦男 田村耕司 竹田明展 于 2018-07-31 设计创作，主要内容包括：一种二甲基亚砜的回收方法,其包括使包含选自二醇醚、二醇和三醇中的至少1种化合物以及二甲基亚砜的回收抗蚀剂剥离剂与水接触并进行蒸馏的工序。(A method for recovering dimethyl sulfoxide, which comprises a step of bringing a recovered resist remover comprising at least 1 compound selected from glycol ethers, diols and triols and dimethyl sulfoxide into contact with water and distilling the same.)

1. A method for recovering dimethyl sulfoxide, which comprises a step of bringing a recovered resist remover comprising at least 1 compound selected from glycol ethers, diols and triols and dimethyl sulfoxide into contact with water and distilling the same.

2. The recovery method according to claim 1, wherein the compound is at least 1 selected from the group consisting of 3-methoxy-3-methyl-1-butanol, diethylene glycol, propylene glycol, glycerol, and 2- (2-methoxyethoxy) ethanol.

3. The recovery process of claim 1, wherein the compound is 3-methoxy-3-methyl-1-butanol.

Technical Field

The present invention relates to a method for recovering dimethyl sulfoxide (DMSO) from a recovered resist stripping agent.

Background

In the production of semiconductor elements and the like by photolithography, after a fine circuit or the like is formed by etching, unnecessary resist films and etching residues are cleaned and removed by using a resist remover. As the resist remover, a sodium hydroxide aqueous solution or a general organic solvent may be used alone, but the remover is insufficient, and various resist removers have been proposed so far for improving the remover.

As a resist remover having high releasability, for example, a resist remover obtained by dissolving quaternary ammonium hydroxide such as tetramethylammonium hydroxide (TMAH) in a mixed solvent of DMSO and glycol ether such as 3-methoxy-3-methyl-1-butanol (MMB) has been used (patent document 1).

Disclosure of Invention

Problems to be solved by the invention

In these days, a used resist remover (recovered resist remover) is generally discarded as an industrial waste. On the other hand, DMSO used in the resist remover as described above is also used as a rinse solution in a rinsing step after resist removal, and the amount used has been significantly increased in recent years. Therefore, it is advantageous in terms of cost and the like if high-purity DMSO can be recovered from the recovered resist remover and reused.

However, DMSO (boiling point: 189 ℃ C.) has a boiling point close to that of glycol ether or the like in many cases (for example, MMB has a boiling point: 174 ℃ C.), and it is difficult to recover high-purity DMSO by a method such as distillation under reduced pressure in general, and it is not practical to reuse DMSO.

The purpose of the present invention is to provide a method for recovering high-purity DMSO from a recovered resist stripping agent at low cost and with high efficiency.

Means for solving the problems

The present inventors have conducted intensive studies and, as a result, have found that: the present inventors have found that high-purity DMSO can be recovered at low cost and efficiently by adding water to a recovered resist remover and distilling the mixture, and further have conducted extensive studies based on the finding, thereby completing the present invention.

The present invention relates to the following [1] to [3 ].

[1] A method for recovering DMSO, which comprises a step of distilling a recovered resist remover comprising DMSO and at least 1 compound selected from glycol ethers, diols and triols by contacting the remover with water.

[2] The recovery method according to [1], wherein the compound is at least 1 selected from the group consisting of 3-methoxy-3-methyl-1-butanol, diethylene glycol, propylene glycol, glycerin and 2- (2-methoxyethoxy) ethanol.

[3] The recovery method according to [1], wherein the compound is 3-methoxy-3-methyl-1-butanol.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the method of the present invention, high-purity DMSO can be recovered from the recovered resist remover at low cost and with high efficiency.

Detailed Description

The method of the present invention is specifically described below.

Typically, the "recovered resist remover" to be a target for recovery of DMSO in the present invention is: a used resist remover which comprises DMSO and at least 1 compound selected from glycol ethers, diols and triols after cleaning and removing unnecessary resist films and the like in lithography.

In addition, the recovered resist remover usually contains quaternary ammonium hydroxide, a resist component, and the like.

Examples of the glycol ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol (MMB), dipropylene glycol monomethyl ether, and 2- (2-methoxyethoxy) ethanol.

Examples of the glycol include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and triethylene glycol.

Examples of the triol include glycerin and the like.

Among these, the above-mentioned compound is preferably at least 1 selected from MMB, diethylene glycol, propylene glycol, glycerin and 2- (2-methoxyethoxy) ethanol, and more preferably MMB.

Examples of the quaternary ammonium hydroxide include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, dimethyldiethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, triethyl (2-hydroxyethyl) ammonium hydroxide, spiro- [1, 1' ] -bipyrrolidinium hydroxide, and the like.

Among these, the quaternary ammonium hydroxide is preferably at least 1 selected from TMAH, tetrapropylammonium hydroxide and spiro- [1, 1' ] -bipyrrolidinium hydroxide, and more preferably TMAH.

The recovered resist remover may contain water, aliphatic alcohol amines, amino acids, surfactants, defoaming agents, and the like as other components.

In the method for recovering DMSO of the present invention, the recovered resist remover is distilled while being contacted with water. This makes it possible to distill off at least 1 compound selected from the group consisting of glycol ether, diol, and triol, and then distill off high-purity DMSO.

The contact of the recovered resist remover with water can be performed by, for example, mixing the recovered resist remover with water. As a specific method for bringing the recovered resist stripping agent into contact with water and distilling the recovered resist stripping agent, for example, a method of adding water to the recovered resist stripping agent and distilling the mixture can be mentioned. In the case of performing such a method of adding water to the recovered resist remover and distilling the same, water may be added to the recovered resist remover all at once and then distilled, or the distillation may be performed while adding water intermittently or at a constant rate.

The temperature during distillation is preferably in the range of 30 to 250 ℃, and more preferably in the range of 50 to 230 ℃. The distillation can be carried out at atmospheric pressure or under reduced pressure.

The amount of water added is preferably in the range of 0.1 to 100 parts by mass, and more preferably in the range of 0.1 to 10 parts by mass, relative to 1 part by mass of the recovered resist remover.