TW201827390A - Method for purifying organic solvent and purification device of organic solvent - Google Patents

Abstract

The present invention addresses the problem of providing an organic solvent refining method with which it is possible to obtain an organic solvent having excellent stability and restrict the occurrence of defects in a semiconductor device, and the present invention addresses the problem of providing an organic solvent refining apparatus. An organic solvent refining method according to the present invention comprises: a distillation step in which an organic solvent containing a stabilizer is distilled, the stabilizer in the organic solvent is diminished, and the content of the stabilizer in the organic solvent is made to be 0.1 to 30 ppm by mass; and after the distillation step, a refining step, in which the organic solvent is refined by using at least one member among a filter member having a filter of which the removed particle size is 20 nm or less and a metal ion adsorbing member, wherein the organic solvent refining method does not comprise an organic impurity removal step for removing organic impurities from the organic solvent by using an organic impurity adsorbing member.

Description

Method for refining organic solvent and refining device for organic solvent

The present invention relates to a method for purifying an organic solvent and a device for purifying an organic solvent.

It is known that a CCD (Charge-Coupled Device) and a semiconductor device such as a memory are manufactured by forming a fine electronic circuit pattern on a substrate by photolithography. In the manufacture of such an electronic circuit pattern, for example, a contact hole and a groove pattern are formed on the insulating film formed on the substrate. Specifically, after the photoresist film obtained by using the sensitizing ray-sensitive or radiation-sensitive composition is formed on the insulating film, exposure processing for irradiating light to the photoresist film, development processing using a developing solution, and A pattern-like resist film can be obtained by various processes such as rinsing treatment of the rinsing liquid. By using the patterned resist film thus obtained as a mask, a substrate having a contact hole or a groove pattern can be obtained by performing an etching treatment on the insulating film. Here, the above-mentioned sensitizing ray-sensitive or radiation-sensitive composition may include an organic solvent. Further, the organic solvent may be used as the developing solution and a pre-wet liquid for improving the coatability of the sensitizing ray-sensitive or radiation-sensitive composition. In the production of a semiconductor device, an organic solvent is widely used. For example, Patent Document 1 discloses a refining device for an organic solvent used in a resist-related material. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2016-73922

The present inventors have found that in order to use in the production of a semiconductor device, when a purified organic solvent is used, the solution characteristics of the organic solvent are lower than those before purification, and the organic solvent used in the production of the semiconductor device cannot be sufficiently exhibited. Performance. The inventors of the present invention conducted research on the problem and found that it is related to the content of the stabilizer in the organic solvent after purification. Here, since the organic impurities are defects of the semiconductor device or the like, the removal is preferable, and for example, a method of removing the organic impurities removal filter or the like can be considered. However, a stabilizer which is one of organic impurities is also removed by the organic impurity removing filter. That is, in the case of purifying an organic solvent, it is difficult to remove the organic impurities other than the stabilizer while retaining the stabilizer in the organic solvent within a predetermined range.

An object of the present invention is to provide a method for purifying an organic solvent capable of suppressing generation of defects in a semiconductor device and an apparatus for purifying an organic solvent, which are capable of obtaining an organic solvent having excellent stability.

As a result of intensive studies on the above problems, the present inventors have found that the content of the stabilizer in the organic solvent is adjusted within a predetermined range by not performing the organic impurity removing step of removing the organic impurities in the organic solvent. The refined organic solvent is excellent in stability and can suppress defects in the semiconductor device until the present invention is completed. That is, the inventors have found that the above problems can be solved by the following configuration.

[1] A method for purifying an organic solvent, comprising: a distillation step of distilling an organic solvent containing a stabilizer to reduce the stabilizer in the organic solvent, and setting the content of the stabilizer in the organic solvent to 0.1 to 0.1 30 mass ppm; and a refining step of purifying the organic solvent by using at least one of a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorbing member after the distilling step, and purifying the organic solvent The method does not include an organic impurity removing step of removing organic impurities in the above organic solvent by an organic impurity adsorbing member. [2] A method for purifying an organic solvent, comprising: a distillation step of performing distillation on an organic solvent not actually containing a stabilizer; and a stabilizer addition step, after the above distillation step, the content of the stabilizer in the organic solvent is 0.1 ～30 mass ppm, a stabilizer is added to the organic solvent; and a purification step is performed after the stabilizer addition step, using at least a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorption member The organic solvent is purified by one member, and the method for purifying the organic solvent does not include an organic impurity removing step of removing organic impurities in the organic solvent by the organic impurity adsorbing member. [3] The method for producing an organic solvent according to [1], wherein a boiling point of the organic solvent is lower than a boiling point of the stabilizer, and a distillation temperature of the organic solvent in the distillation step is at least a boiling point of the organic solvent, and It is lower than the boiling point of the above stabilizer. [4] The method for purifying an organic solvent according to [2], wherein a distillation temperature of the organic solvent in the distillation step is at least a boiling point of the organic solvent. [5] The method for purifying an organic solvent according to [3] or [4] wherein the distillation temperature is 150 to 240 °C. [6] The method for purifying an organic solvent according to any one of [1] to [5] wherein the metal ion adsorbing member is provided with a metal ion adsorption filter capable of ion exchange, and the metal ion adsorption filter is on the surface Has an acid group. [7] The method for purifying an organic solvent according to any one of [1] to [6] wherein the organic solvent is stored in a tank, and the organic solvent is circulated by a pump connected to the tank via a supply pipe. At the same time, the above-described purification step is carried out, and the liquid contact portion of the tank, the liquid contact portion of the supply pipe, and the liquid contact portion of the pump are each formed of a fluororesin. [8] The method for purifying an organic solvent according to any one of [1] to [7] wherein the purification step is carried out twice or more. [9] The method for purifying an organic solvent according to any one of [1] to [8] wherein the organic solvent is selected from the group consisting of n-butanol, 4-methyl-2-pentanol, and propylene glycol monomethyl ether. Propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl acetate, isoamyl acetate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butane An organic solvent of at least one of a group consisting of an ester and diisoamyl ether. [10] The method for purifying an organic solvent according to any one of [1] to [9] wherein the organic solvent is used as a pre-wetting liquid, a developing solution, and a sensitizing ray-sensitive or radiation-sensitive composition At least one of the solvents contained in the solvent. [11] An apparatus for purifying an organic solvent, comprising: a tank for storing an organic solvent; a pump connected to the tank and circulating the organic solvent; a distillation unit for distilling the organic solvent; and a removal particle diameter of 20 nm or less At least one of the filter member of the filter and the metal ion adsorbing member, the organic solvent purifying device does not have an organic impurity adsorbing member that removes organic impurities in the organic solvent. [12] The apparatus for purifying an organic solvent according to [11], wherein the metal ion adsorbing member includes a metal ion adsorption filter capable of ion exchange, and the metal ion adsorption filter has an acid group on a surface. [13] The apparatus for purifying an organic solvent according to [11], wherein the liquid contact portion of the tank and the liquid contact portion of the pump are each formed of a fluororesin. [14] The apparatus for purifying an organic solvent according to any one of [11] to [13] further comprising a supply tube that connects the tank and the pump, wherein the liquid contact portion of the supply tube is formed of a fluororesin. [15] The apparatus for purifying an organic solvent according to any one of [11] to [14] wherein the organic solvent is selected from the group consisting of n-butanol, 4-methyl-2-pentanol, and propylene glycol monomethyl ether. Propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl acetate, isoamyl acetate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butane An organic solvent of at least one of a group consisting of an ester and diisoamyl ether. [16] The apparatus for purifying an organic solvent according to any one of [11], wherein the organic solvent is used as a pre-wetting liquid, a developing solution, and a sensitizing ray-sensitive or radiation-sensitive composition. At least one of the solvents contained in the solvent. [Effect of the invention]

As described below, according to the present invention, it is possible to provide a method for purifying an organic solvent capable of suppressing generation of defects in a semiconductor device and an apparatus for purifying an organic solvent, which are capable of obtaining an organic solvent having excellent stability.

Hereinafter, the present invention will be described. In addition, in the present invention, the numerical range represented by "to" means a range in which the numerical values described before and after "~" are included as the lower limit and the upper limit. Further, in the present invention, the term "preparation" means that, in addition to preparation for synthesis or preparation of a predetermined material, it is also included to purchase a predetermined article by purchase or the like. Also, in the present invention, "ppm" means "parts per million, parts-per-million (10 ^-6 )", and "ppb" means "one billionth, parts-per-billion (10) ^-9 )”, “ppt” means “one trillion, parts-per-trillion (10 ^-12 )”. Further, the term "radiation" in the present invention means, for example, a far-line ultraviolet ray represented by a bright line spectrum of a mercury lamp, an excimer laser, an extreme ultraviolet ray (EUV light), an X-ray or an electron beam. Further, in the present invention, light means actinic rays or radiation. The "exposure" in the present invention includes not only exposure based on a far-ultraviolet light represented by a mercury lamp or an excimer laser, X-ray or EUV light but also a particle line based on an electron beam or an ion beam, unless otherwise specified. Belong to exposure.

The method for purifying the organic solvent of the present invention does not perform the step of removing the organic impurities in which the organic impurities in the organic solvent are removed, but has a step of adjusting the content of the stabilizer in the organic solvent within a predetermined range, thereby purifying the organic The stability of the solvent is excellent, and it is also possible to suppress defects in the semiconductor device. Although the details of this reason are not clear, it is presumed to be based on the following reasons. The organic solvent sometimes contains various impurities such as inorganic impurities (for example, metal ions and metal fine particles) and organic impurities. These impurities may be eluted from the components (for example, piping, cans, etc.) of the manufacturing apparatus used in the production of the organic solvent, and the organic solvent storage container, etc., and may be mixed in the organic solvent. Further, a raw material used in the production of an organic solvent, a by-product of an organic solvent, and a structural isomer of an organic solvent may be contained as an impurity in an organic solvent. Such various impurities contained in an organic solvent sometimes cause defects in the semiconductor device, and therefore it is preferable to remove as much as possible. For example, for organic impurities in various impurities, a method of removing using an organic impurity adsorbing member or the like can be considered. However, the inventors have found that when an organic solvent obtained by removing organic impurities is used in the manufacture of a semiconductor device, the organic solvent cannot sufficiently exhibit the original performance, and sometimes the organic solvent used in the manufacture of the semiconductor device cannot be achieved. The required performance. Here, in the case of producing an organic solvent, a stabilizer is used for the purpose of improving stability during storage, etc., and therefore a stabilizer may be contained in the organic solvent after production. The present inventors have found that when the stabilizer in the organic solvent is excessively removed by the organic impurity adsorbing member used in the purification, the stability of the purified organic solvent is lowered. In addition, when the content of the stabilizer in the organic solvent after purification is increased, the present inventors increase the residual amount of the stabilizer in the semiconductor device, which is a cause of defects in the semiconductor device. On the other hand, the organic solvent before purification may not actually contain a stabilizer. At this time, even if the content of the stabilizer in the organic solvent is insufficient after the purification step is performed, the stability of the organic solvent after purification is lowered. According to this finding, a method of controlling the content of the stabilizer in the organic solvent to a predetermined range while removing organic impurities other than the stabilizer has been studied. As a result, it was found that when the content of the stabilizer in the organic solvent before purification is too large, a part of the organic impurities containing the stabilizer is removed by the distillation step, and the organic solvent purification method does not perform the organic impurity removal step, thereby After the refining step, the refined organic solvent is still excellent in stability, and can suppress defects in the semiconductor device when used in the manufacture of a semiconductor device. Further, it has been found that when the content of the stabilizer in the organic solution before purification is too small, the organic impurities are removed by the distillation step, and then the step of adding the stabilizer to a predetermined range is performed, and the organic impurity removal step is not performed. Thereby, even after the refining step, the refined organic solvent is excellent in stability, and it is possible to suppress defects in the semiconductor device when used in the manufacture of a semiconductor device.

Hereinafter, the procedure of purifying the organic solvent and the method of purifying the organic solvent will be described.

[An apparatus for purifying an organic solvent] The apparatus for purifying an organic solvent of the present invention comprises: a tank for storing an organic solvent; a pump connected to the tank and circulating the organic solvent; a distillation unit for distilling the organic solvent; and having a removal The filter member of the filter having a particle diameter of 20 nm or less and at least one of the metal ion adsorbing members do not have an organic impurity adsorbing member that removes organic impurities in the organic solvent. In the following, an embodiment of the organic solvent purification apparatus of the present invention (hereinafter simply referred to as "the organic solvent purification apparatus of the present embodiment") will be specifically described with reference to the drawings, but the present invention is not limited to the following embodiments. By.

Fig. 1 is a schematic view showing a configuration of an organic solvent purification device 100 (hereinafter simply referred to as "refining device 100") of the present embodiment. The refining device 100 has a tank 10 for storing an organic solvent, a pump 20 connected to the tank 10 and circulating an organic solvent, a distillation unit 50 for distilling the organic solvent, a first metal ion adsorption filter 32, and a filter member 40. A filter having a particle diameter of 20 nm or less is removed, and a second metal ion adsorption filter 34 is provided. The first metal ion adsorption filter 32 and the second metal ion adsorption filter 34 are constituent elements of the metal ion adsorption member 30. Further, the refining device 100 has a supply pipe 60. The supply pipe 60 can be used as an organic solvent in the tank 10, the pump 20, the distillation unit 50 that distills the organic solvent, the first metal ion adsorption filter 32, the filter member 40, and the second metal ion adsorption filter 34. The components are connected in a distributed manner.

Specifically, the organic solvent stored in the tank 10 is circulated in the refining device 100 as follows. When the pump 20 is started, the organic solvent stored in the tank 10 passes through the supply pipe 60, the pump 20, the distillation unit 50 that distills the organic solvent, the first metal ion adsorption filter 32, the filter member 40, and the second metal. The ion adsorption filter 34 is sequentially flowed and then recovered into the tank 10.

[Canister] Tank 10 is used for storage and recovery of organic solvents. As the material of the can 10, it is preferable to use a known stainless steel from the viewpoint of suppressing contamination from organic substances. Among them, an alloy containing 8% by mass or more of nickel is preferable, and an austenitic stainless steel containing 8% by mass or more of nickel is more preferable. Examples of the austenitic stainless steel include SUS (stainless steel, Steel Use Stainless) 304 (Ni content: 8 mass%, Cr content: 18 mass%), SUS304L (Ni content: 9 mass%, and Cr content: 18 mass%), and SUS316. (Ni content: 10% by mass, Cr content: 16% by mass), and SUS316L (Ni content: 12% by mass, Cr content: 16% by mass). Further, as the material of the can 10, in the above stainless steel, stainless steel which is electrolytically polished is preferable. The method of electrolytically polishing stainless steel is not particularly limited, and a known method can be used. For example, the methods described in paragraphs [0011] to [0014] of JP-A-2015-227501, and paragraphs [0036] to [0042] of JP-A-2008-264929 can be used. It can be inferred that a metal material such as stainless steel is obtained by electrolytically grinding, and the content of chromium in the passivation layer of the surface becomes larger than the content of chromium in the mother phase. Therefore, it can be inferred that the metal component from the electrolytically ground metal material does not easily flow out into the solution, so that a solution (organic solvent) in which the metal component (metal impurity) is reduced can be obtained. Among them, the Cr/Fe ratio of stainless steel is preferably 3 or more in atomic % ratio. By having the above Cr/Fe ratio, it is more difficult for the metal component to flow out into the solution, and the metal component (metal impurity) in the solution can be further reduced. The liquid contact portion of the can 10 is preferably a fluororesin from the viewpoint of suppressing the incorporation of impurities derived from the can 10 into the organic solvent. Further, in the present invention, the "liquid contact portion" means a portion where the organic solvent is in contact with each member. Examples of the fluororesin include polytetrafluoroethylene resin (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene. - ethylene copolymer (ETFE), chlorotrifluoroethylene-ethylene copolymer (ECTFE), polyvinylidene fluoride resin (PVDF), polychlorotrifluoroethylene resin (PCTFE), and polyvinyl fluoride resin (PVF).

[Pump] The pump 20 is not particularly limited as long as it can circulate the organic solvent in the refining device 100, and a known pump can be used. The liquid contact portion of the pump 20 is preferably a fluororesin from the viewpoint of suppressing the incorporation of impurities derived from the material of the pump 20 into the organic solvent. Specific examples of the fluororesin are as described above.

[Distillation Unit] The distillation unit 50 is not particularly limited as long as it has a function of distilling an organic solvent, and a known distillation column is preferably used. The distillation method of the distillation column may be either a filler method or a plate type, but a plate type is preferable from the viewpoint of more effectively separating the organic impurities and the stabilizer from the organic solvent. The inside of the plate distillation column is distinguished by a plurality of plates arranged horizontally, and multi-stage distillation can be performed by using a plate distillation column. The preferred embodiment of the material of the distillation unit 50 is the same as that of the above-described tank 10, and thus the description thereof will be omitted. Further, for the same reason as the above-described tank 10, the liquid contact portion of the distillation portion 50 is preferably made of glass or stainless steel or fluororesin which is electrolytically polished as described in the description of the tank 10. When the distillation section employs a large-scale apparatus, the fluororesin or the electrolytically ground stainless steel is more preferable from the viewpoint of obtaining the desired effect of the present invention and the strength.

[Metal Ion Adsorption Member] As shown in FIG. 1 , the metal ion adsorption member 30 includes a first metal ion adsorption filter 32 and a second metal ion adsorption filter 34 . In the following description, when simply referred to as "metal ion adsorption filter", both the first metal ion adsorption filter 32 and the second metal ion adsorption filter 34 are shown. The metal ion adsorption filter has a function of adsorbing metal ions in an organic solvent. Further, the metal ion adsorption filter is preferably a filter capable of ion exchange. Here, the metal ions to be adsorbed are not particularly limited, but Fe, Cr, Ni, and Pb are preferable from the viewpoint of easily causing defects in the semiconductor device. From the viewpoint of improving the adsorption performance of metal ions, it is preferred that the metal ion adsorption filter has an acid group on the surface. Examples of the acid group include a sulfo group and a carboxyl group. Examples of the substrate (material) constituting the metal ion adsorption filter include cellulose, diatomaceous earth, nylon, polyethylene, polypropylene, polystyrene, fluororesin, polyimine, and polyamine. Amines, combinations of these, and the like. Specific examples of the metal ion adsorption filter including at least one of a polyimine and a polyamidimide include polyethylenimine and/or polyfluorene described in JP-A-2016-155121. Amine-imine porous membrane. The polyimine and/or the polyamidimide porous film may have at least one selected from the group consisting of a carboxyl group, a salt type carboxyl group, and a —NH— bond. The solvent resistance is preferably a fluororesin, a polyimine, or a polyamidoximine.

[Filter Member] The filter member 40 is provided with a filter having a particle diameter of 20 nm or less. The organic solvent passes through the filter of the filter member 40, whereby particulate impurities can be removed from the organic solvent. Here, examples of the "particulate impurities" include particles such as dirt, dust, organic solids, and inorganic solids contained as impurities in the raw materials used in the production of the organic solvent, and contamination as a result of refining the organic solvent. The soil, dust, organic solids, inorganic solid particles, and the like brought in by the matter correspond to those which are not dissolved in the organic solvent and are present as particles. Further, the "particulate impurities" also include colloidal impurities containing metal atoms. The metal atom is not particularly limited, and is selected from the group consisting of Na, K, Ca, Fe, Cu, Mg, Mn, Li, Al, Cr, Ni, Zn, and Pb (Fe, Cr, Ni, and Pb are preferred). When the content of at least one of the metal atoms is particularly low (for example, when the content of the metal atom in the organic solvent is 1000 mass% or less, respectively), the impurities containing the metal atoms are easily colloidalized. It is difficult to remove colloidal impurities by the above metal ion adsorbing member. Therefore, by using a filter having a particle diameter of 20 nm or less (for example, a microfiltration membrane having a pore diameter of 20 nm or less), it is possible to effectively remove colloidal impurities. The particulate impurities have a size that can be removed by a filter having a particle diameter of 20 nm or less, and specifically, particles having a diameter of 20 nm or more. Further, in the present specification, particulate impurities may be referred to as "coarse particles". The filter having the filter member 40 has a removal particle diameter of 20 nm or less, and preferably has a particle diameter of 1 to 15 nm, preferably 1 to 12 nm. By removing the particle diameter of 15 nm or less, finer particulate impurities can be removed, and by removing the particle diameter of 1 nm or more, the filtration efficiency of the organic solvent is improved. Here, the removal of the particle diameter refers to the minimum size of the particles that the filter can remove. For example, when the particle size of the filter is 20 nm, particles having a diameter of 20 nm or more can be removed. Examples of the material of the filter provided in the filter member 40 include 6-nylon, 6,6-nylon, polyethylene, polypropylene, polystyrene, fluororesin, polyimine, and polyamidimide. And combinations of these, etc. At least one of the polyimine and the polyamidimide may be at least one selected from the group consisting of a carboxyl group, a salt type carboxyl group, and a -NH- bond. The solvent resistance is preferably a fluororesin, a polyimine, or a polyamidoximine.

The filter member 40 may further include a filter (for example, a microfiltration membrane for removing fine particles having a pore diameter of 50 nm or more) having a particle diameter of 50 nm or more. When there are fine particles in addition to colloidal impurities, especially colloidal impurities such as iron or aluminum, in the treatment liquid, a filter having a particle diameter of 20 nm or less (for example, a pore diameter of 20 nm or less) is used. Before the filtration membrane), a filter having a particle diameter of 50 nm or more (for example, a fine filtration membrane for removing fine particles having a pore diameter of 50 nm or more) is used to carry out filtration of an organic solvent, and a filter having a particle diameter of 20 nm or less is removed ( For example, the filtration efficiency of a fine filtration membrane having a pore diameter of 20 nm or less, or the performance of removing coarse particles is further improved.

[Organic Impurity Absorbing Member] The refining device 100 does not have an organic impurity adsorbing member for removing organic impurities in the organic solvent. In the present invention, the organic impurities mean organic substances other than the organic solvent. Specifically, examples of the organic impurities include a stabilizer (described later) used in the production of an organic solvent, an unreacted raw material, structural isomers and by-products produced in the production of an organic solvent, and constituent organic solvents. The elution of a member such as a manufacturing apparatus used (for example, a plasticizer eluted from a rubber member such as an O-ring) or the like.

Here, when the organic solvent is, for example, an alcohol compound, a ketone compound, an ester compound, an ether compound, or an aldehyde compound, examples of the organic impurities derived from the organic solvent include unreacted materials or by-products when the organic solvent is produced. An alcohol compound, a ketone compound, an ester compound, an ether compound, an aldehyde compound, or the like. Specific examples of the impurities derived from the organic solvent include compounds represented by the following formulas I to V.

[Chemical Formula 1]

Among them, since the carbon number is 6 or more and the boiling point is high, it is liable to remain on the substrate used for the semiconductor device, which is likely to cause defects.

In the formula I, R ₁ and R ₂ each independently represent an alkyl group or a cycloalkyl group. R ₁ and R ₂ may be bonded to each other to form a ring. The alkyl group represented by R ₁ and R ₂ is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. The cycloalkyl group represented by R ₁ and R ₂ is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 8 carbon atoms. The ring formed by bonding R ₁ and R _{2 to} each other is a lactone ring, the lactone ring of a 4- to 9-membered ring is preferred, and the lactone ring of a 4- to 6-membered ring is more preferable. Further, it is preferred that R ₁ and R ₂ satisfy the relationship that the carbon number of the compound represented by Formula I is 6 or more.

In the formula II, R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group or a cycloalkenyl group. R ₃ and R ₄ may be bonded to each other to form a ring. Among them, there is no case where both R ₃ and R ₄ are hydrogen atoms. The alkyl group represented by R ₃ and R ₄ is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. As the alkenyl group of R ₃ and R ₄ represents the, for example, carbon alkenyl group is preferably 2 to 12, carbon atoms, an alkenyl group having 2 to 8 is preferred. The cycloalkyl group represented by R ₃ and R ₄ is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 8 carbon atoms. The cycloalkenyl group represented by R ₃ and R ₄ is preferably a cycloalkenyl group having 3 to 12 carbon atoms, more preferably a cycloalkenyl group having 6 to 8 carbon atoms. The ring formed by bonding R ₃ and R _{4 to} each other is a cyclic ketone structure, and may be a saturated cyclic ketone or an unsaturated cyclic ketone. The cyclic ketone is preferably a 6 to 10 membered ring, and more preferably a 6 to 8 membered ring. Further, it is preferred that R ₃ and R ₄ satisfy the relationship that the carbon number of the compound represented by Formula II is 6 or more.

In the formula III, R ₅ represents an alkyl group or a cycloalkyl group. The alkyl group represented by R ₅ is preferably an alkyl group having 6 or more carbon atoms, more preferably an alkyl group having 6 to 12 carbon atoms, and more preferably an alkyl group having 6 to 10 carbon atoms. The alkyl group may have an ester bond in the chain, and may have a substituent such as a hydroxyl group. The cycloalkyl group represented by R ₅ is preferably a cycloalkyl group having 6 or more carbon atoms, more preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 10 carbon atoms.

In the formula IV, R ₆ and R ₇ each independently represent an alkyl group or a cycloalkyl group. R ₆ and R ₇ may be bonded to each other to form a ring. The alkyl group represented by R ₆ and R ₇ is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. The cycloalkyl group represented by R ₆ and R ₇ is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 8 carbon atoms. The ring formed by bonding R ₆ and R _{7 to} each other is a cyclic ester structure. The cyclic ester structure is preferably a 4- to 8-membered ring, and a 5- to 7-membered ring is more preferred. Further, it is preferred that R ₆ and R ₇ satisfy the relationship that the carbon number of the compound represented by Formula IV is 6 or more.

In the formula V, R ₈ and R ₉ each independently represent an alkyl group or a cycloalkyl group. R ₈ and R ₉ may be bonded to each other to form a ring. L represents a single bond or an alkyl group. The alkyl group represented by R ₈ and R ₉ is preferably an alkyl group having 6 to 12 carbon atoms, more preferably an alkyl group having 6 to 10 carbon atoms. The cycloalkyl group represented by R ₈ and R ₉ is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 10 carbon atoms. The ring formed by bonding R ₈ and R _{9 to} each other is a cyclic diketone structure. The cyclic diketone structure is preferably a 6 to 12 membered ring, and a 6 to 10 membered ring is more preferred. The alkylene group represented by L is preferably an alkylene group having 1 to 12 carbon atoms, and more preferably an alkylene group having 1 to 10 carbon atoms. Further, it is preferred that R ₈ , R ₉ and L satisfy the relationship that the carbon number of the compound represented by the formula V is 6 or more.

In addition, when the organic solvent is a guanamine compound, a ruthenium compound, or a ruthenium compound, the organic impurity derived from the organic solvent may, for example, be an unreacted substance in the purification of an organic solvent or An alcohol compound, a ketone compound, an ester compound, an ether compound, and an aldehyde compound as by-products. Among them, those having a carbon number of 6 or more have a high boiling point, and thus tend to remain on the semiconductor processing substrate, which is likely to cause defects. As such a compound, the following compounds are mentioned, for example.

[Chemical Formula 2]

[Chemical Formula 3]

Further, as the organic impurities, a resin material used as a member for manufacturing a device, a resin component contained in a rubber member (for example, an O-ring, etc.), a plasticizer, and the like (for example, dioctyl phthalate, ortho-benzene) can be considered. Examples of diisodecyl diformate and dibutyl phthalate may be eluted from the solution at any time during the production process.

Since the refining device 100 does not have an organic impurity adsorbing member, it is possible to suppress the stabilizer from being removed from the organic solvent, thereby maintaining the stability of the purified organic solvent. Here, as the organic impurity adsorbing member, for example, an organic impurity adsorbing filter having an organic skeleton capable of interacting with organic impurities on the surface (in other words, an organic skeleton capable of interacting with organic impurities) may be mentioned. Modified organic impurity adsorption filter). Examples of the organic skeleton capable of interacting with organic impurities include a chemical structure capable of capturing organic impurities in an organic impurity adsorption filter by reacting with organic impurities. More specifically, when an n-long-chain alkyl alcohol (a structural isomer when a 1-long-chain alkyl alcohol is used as an organic solvent) is contained as an organic impurity, an alkyl group is exemplified as the organic skeleton. Further, when dibutylhydroxytoluene (BHT) is contained as an organic impurity, a phenyl group is exemplified as the organic skeleton. Examples of the substrate (material) constituting the organic impurity adsorption filter include cellulose carrying activated carbon, diatomaceous earth, nylon, polyethylene, polypropylene, polystyrene, and fluororesin. In addition, as the organic impurity adsorption filter, a filter in which activated carbon described in JP-A-2002-273123 and JP-A-2013-150979 is adhered to a nonwoven fabric is also known.

The organic impurity adsorbing member may be a physical adsorption mechanism in addition to the chemical adsorption described above (the adsorption using an organic impurity removing filter having an organic skeleton capable of interacting with organic impurities on the surface). For example, when BHT is contained as an organic impurity, the structure of BHT is larger than 10 Å (=1 nm). Therefore, by removing the filter using organic impurities having a pore diameter of 1 nm, the BHT cannot pass through the pores of the filter. That is, the BHT is physically trapped by the filter and thus removed from the organic solvent. Thus, organic impurities may be removed by physical removal methods not only by chemical interaction. Here, at this time, a filter having a pore diameter of 3 nm or more was used as the "filter member", and a filter having a pore diameter of less than 3 nm was used as the "organic impurity removal filter". In the present specification, 1 Å (angstrom) corresponds to 0.1 nm.

[Supply Tube] The supply tube 60 connects the above-described members so that the organic solvent can flow through the refining device 100. The material of the supply pipe 60 is not particularly limited. However, from the viewpoint of suppressing impurities in the material of the supply pipe 60 from being mixed in the organic solvent, the liquid contact portion is preferably a fluororesin. Specific examples of the fluororesin are as described above.

The liquid contact portion of the tank 10 and the pump 20 is preferably a fluororesin, and the liquid contact portions of the tank 10, the pump 20, and the supply pipe 60 are preferably fluororesin. Thereby, it is possible to further suppress the incorporation of impurities into the organic solvent. Specific examples of the fluororesin are as described above.

[Organic solvent] The organic solvent to be used in the purification by the refining device 100 is not particularly limited, and various organic solvents used in the manufacturing process of the semiconductor device, and various types used in the manufacturing process of the semiconductor device can be cited. The various organic solvents used in the course of the material, specifically, methanol, ethanol, 1-propanol, isopropanol, n-propanol, 2-methyl-1-propanol, n-butanol, 2- Butanol, tertiary butanol, 1-pentanol, 2-pentanol, 3-pentanol, n-hexanol, cyclohexanol, 2-methyl-2-butanol, 3-methyl-2-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methoxybutanol, 3-methyl-3-methoxybutanol, 2-methyl-1-pentanol , 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol , 4-methyl-1-pentanol, 4-methyl-2-pentanol (MIBC), 2-ethyl-1-butanol, 2,2-dimethyl-3-pentanol, 2,3 - dimethyl-3-pentanol, 2,4-dimethyl-3-pentanol, 4,4-dimethyl-2-pentanol, 3-ethyl-3-pentanol, 1-heptanol , 2-heptanol, 3-heptanol, 2-methyl-2-hexanol, 2-methyl-3-hexanol, 5-methyl 1-hexanol, 5-methyl-2-hexanol, 2-ethyl-1-hexanol, methylcyclohexanol, trimethylcyclohexanol, 4-methyl-3-heptanol, 6 -methyl-2-heptanol, 1-octanol, 2-octanol, 3-octanol, 2-propyl-1-pentanol, 2,4,4-trimethyl-1-pentanol, 2 ,6-Dimethyl-4-heptanol, 3-ethyl-2,2-dimethyl-pentanol, 1-nonanol, 2-nonanol, 3,5,5-trimethyl-1- Hexanol, 1-nonanol, 2-nonanol, 4-nonanol, 3,7-dimethyl-1-octanol, 3,7-dimethyl-3-octanol, ethylene glycol, propylene glycol, Diethyl ether, dipropyl ether, diisopropyl ether, butyl methyl ether, butyl ether, butyl propyl ether, dibutyl ether, diisobutyl ether, tertiary butyl methyl ether, tertiary butyl ether, tertiary butyl ether , di-tertiary butyl ether, dipentyl ether, diisoamyl ether, dihexyl ether, dioctyl ether, cyclopentyl methyl ether, cyclohexyl methyl ether, cyclododecyl methyl ether, cyclopentyl ether, ring Hexylethyl ether, cyclopentyl propyl ether, cyclopentyl-2-propyl ether, cyclohexyl propyl ether, cyclohexyl-2-propyl ether, cyclopentyl butyl ether, cyclopentyl-tertiary butyl ether, cyclohexyl butyl ether , cyclohexyl-tertiary butyl ether, bromomethyl methyl ether, iodine methyl methyl ether, α,α-dichloromethyl methyl ether, chloromethyl Ether, 2-chloroethyl methyl ether, 2-bromoethyl methyl ether, 2,2-dichloroethyl methyl ether, 2-chloroethyl ether, 2-bromoethyl ether, (±)-1,2 -dichloroethyl ether, di-2-bromoethyl ether, 2,2,2-trifluoroethyl ether, chloromethyl octyl ether, bromomethyl octyl ether, di-2-chloroethyl ether, ethyl vinyl ether, Butyl vinyl ether, allyl ether, allyl propyl ether, allyl butyl ether, diallyl ether, 2-methoxy propylene, ethyl -1-propenyl ether, 1-methoxy- 1,3-butadiene, cis-1-bromo-2-ethoxyethylene, 2-chloroethyl vinyl ether, allyl-1,1,2,2-tetrafluoroethyl ether, octane , isooctane, decane, decane, methylcyclohexane, decahydronaphthalene, xylene, pentylbenzene, ethylbenzene, diethylbenzene, cumene, grade 2-butylbenzene, cymene , dipentene, γ-butyrolactone (γ-BL), isophorone, methyl pyruvate, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether (PGEE), propylene glycol monopropyl ether (PGPE), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, ethyl lactate (EL), pyruvic acid Methyl methoxypropionate, ethyl ethoxypropionate, butyl butyl acetate, butyl butyl propionate, propylene glycol monoterpbutyl butyl ether acetate, cyclopentanone (CyPe), cyclohexanone (CyHe), propylene glycol dimethyl ether, diethylene glycol dimethyl ether, methyl-2-pentanone, butyl acetate (nBA), isoamyl acetate, chloroform, cyclophenyl methyl ether, dichloromethane, 1 , 4-dioxane, tetrahydrofuran, and the like. Among these, an organic solvent which can be used as a pre-wetting liquid or a developing solution in a semiconductor device manufacturing step, and a diluent which can be used as a resist material in a photosensitive ray-sensitive or radiation-sensitive resin composition An organic solvent is preferred, and specifically, it can be more preferably selected from the group consisting of n-butanol, 4-methyl-2-pentanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and propylene glycol monomethyl ether. At least one organic group consisting of an acid ester, ethyl lactate, butyl acetate, isoamyl acetate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, and diisoamyl ether Solvent. The organic solvent can be used in combination of two or more kinds in any ratio. Although it is not particularly limited, it is possible to further reduce the occurrence of defects in the semiconductor device by combining two or more kinds of organic solvents having different boiling points, solubility parameters, or relative dielectric constants. For example, by using an organic solvent having a relatively low dielectric constant, it is possible to reduce the occurrence of defects of the electrostatic-based semiconductor device.

In the present invention, it is preferable to use at least one type of ether from the viewpoint of further reducing the occurrence of defects in the semiconductor device when used in combination of two or more kinds of organic solvents. More than one type of ether is preferred. When two or more kinds of ethers are combined, as a combined ether, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl Ether is preferred. Among these, a combination (mixed solvent) of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether is preferred. When two kinds of organic solvents are used in combination, the mixing ratio (mass) is preferably from 1/99 to 99/1, more preferably from 10/90 to 90/10, and further preferably from 20/80 to 60/40. Although not particularly limited, three or more organic solvents may be further mixed at an arbitrary ratio. This may cause minor resist shape adjustment, viscosity adjustment, and the like. Examples of the combination include PGMEA/PGME/γ-butyrolactone, PGMEA/PGME/cyclohexanone, PGMEA/PGME/2-heptanone, PGMEA/cyclohexanone/γ-butyrolactone, and PGMEA/γ- Butyrolactone/2-heptanone and the like.

As an organic solvent and a raw material in the production of an organic solvent, it is possible to purchase a high-purity grade product (especially a metal ion and a content of organic impurities), and use them in a distillation step and a purification step which will be described later.

[Stabilizer] The stabilizer is a component contained in an organic solvent, and is mainly used in the production of an organic solvent, and has a function of suppressing the deterioration of the performance of the solution of the organic solvent over time. As described above, the stabilizer is often used in the production of an organic solvent, and the organic solvent (that is, the organic solvent before purification) used in the purification apparatus 100 of the present invention may contain a stabilizer. Further, from the viewpoint of ensuring the stability (purity stability) of the organic solvent after purification, it is preferable to further contain a stabilizer in the organic solvent after purification, after the organic solvent is purified by the refining device 100 of the present invention. The stabilizer is not particularly limited as long as it is a stabilizer which is usually used as an organic solvent, and examples thereof include an antioxidant and a chelating agent.

The antioxidant is not particularly limited, and examples thereof include a phenol-based antioxidant, a hindered amine-based antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant, a benzotriazole-based antioxidant, a benzophenone-based antioxidant, and a hydroxylamine. It is an antioxidant, a salicylate antioxidant, and a triazine antioxidant.

As a phenol type antioxidant, a hindered phenol type antioxidant is mentioned, for example. Examples of the hindered phenol-based antioxidant include 2,4-bis[(laurylthio)methyl]-o-cresol and 1,3,5-tris(3,5-di-tertiary butyl- 4-hydroxybenzyl), 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl), 2,4-bis-(n-octylthio)- 6-(4-hydroxy-3,5-di-tertiary butylanilino)-1,3,5-triazine, pentaerythritol tetrakis[3-(3,5-di-tertiary butyl- 4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-4-nonylphenol, 2,2'-isobutylene-bis-(4,6-dimethyl-phenol) 4,4'-butylidene-bis-(2-tert-butyl-5-methylphenol), 2,2'-thio-bis-(6-tributyl-4-methylphenol) , 2,5-di-tris-pentyl hydroquinone, 2,2'-thiodiethyl bis-(3,5-di-tertiary butyl-4-hydroxyphenyl)-propionate, 1,1,3-tri-(2'-methyl-4'-hydroxy-5'-tris-butylphenyl)-butane, 2,2'-methylene-bis-(6-(1) -Methyl-cyclohexyl)-p-cresol), 2,4-dimethyl-6-(1-methyl-cyclohexyl)-phenol, N,N-hexamethylenebis(3,5- Di-tertiary butyl-4-hydroxy-hydrocinnamate, 4,4'-butylenebis-(6-tri-butyl-3-methylphenol) and 2,2'-methylene double -(4-ethyl-6-tertiary butanol) and the like. Other oligomer types having a hindered phenol structure, compounds of a polymer type, and the like can also be used. Further, examples of the phenol-based antioxidant include dibutylhydroxytoluene and hydroquinone in addition to the above-mentioned hindered phenol-based antioxidant.

Examples of the hindered amine-based antioxidant include bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate and bis(N-methyl-2,2,6,6- Tetramethyl-4-piperidinyl) sebacate, N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,6-hexanediamine, 2 -methyl-2-(2,2,6,6-tetramethyl-4-piperidinyl)amino-N-(2,2,6,6-tetramethyl-4-piperidinyl)-propyl Indoleamine, tetrakis(2,2,6,6-tetramethyl-4-piperidinyl) (1,2,3,4-butane tetracarboxylate, poly[{6-(1,1,3) ,3-tetramethylbutyl)imido-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidinyl) Amino}hexamethyl{(2,2,6,6-tetramethyl-4-piperidinyl)imido}], poly[(6-morpholinyl-1,3,5-triazine- 2,4-diyl){(2,2,6,6-tetramethyl-4-piperidinyl)imido}hexamethyl{(2,2,6,6-tetramethyl-4- a piperidinyl)imine}], a polycondensate with dimethyl succinate and 1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine, and N,N'-4,7-tetra[4,6-bis{N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino}-1 , 3,5-triazin-2-yl]-4,7-diazadecane-1,10-diamine, etc. It is also possible to use other Oligomer and polymer type structures amine type compound.

Examples of the phosphorus-based antioxidant include tris(isodecyl)phosphite, tris(tridecyl)phosphite, phenylisooctylphosphite, phenylisodecylphosphite, and phenyl. Di(tridecyl) phosphite, diphenylisooctyl phosphite, diphenylisodecyl phosphite, diphenyltridecyl phosphite, triphenyl phosphite, three (nonylphenyl) phosphite, 4,4'-isopropylidene diphenol alkyl phosphite, tridecyl phenyl phosphite, tridecyl phenyl phosphite, three (2, 4-di-tertiary butylphenyl)phosphite, tris(biphenyl)phosphite, distearyl pentaerythritol diphosphite, bis(2,4-di-tertiary butyl Phenyl) pentaerythritol phosphite, bis(nonylphenyl)neopentitol phosphite, phenylbisphenol A neopentyl phosphite, tetrakis(tridecyl) 4,4' - Butylene bis(3-methyl-6-tertiary butyl phenol) diphosphite, hexadecyl (tridecyl) 1,1,3-tris(2-methyl-4-hydroxy-5-three Butyl phenyl) butane triphosphite, 3,5-di-tertiary butyl-4-hydroxybenzyl phosphite diethyl , sodium bis(4-tert-butylphenyl) phosphite, sodium-2,2-methylene-bis(4,6-di-tertiary butylphenyl)-phosphite, 1,3 - bis(diphenoxyphosphoniumoxy)-benzene, and bis(2,4-ditributylbutyl-6-methylphenyl)phosphite, and the like. Other oligomer types having a phosphite structure, a compound of a polymer type, and the like can also be used.

Examples of the sulfur-based antioxidant include 2,2-thio-divinyl bis[3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate] and 2,4-double. [(octylthio)methyl]-o-cresol, 2,4-bis[(laurylthio)methyl]-o-cresol, 3,3'-thiodipropionate di(dodecane An ester, a di(octadecyl) 3,3'-thiodipropionate, and a di(tetradecyl) 3,3' thiodipropionate. Other oligomer types having a thioether structure, compounds of a polymer type, and the like can also be used.

As the benzotriazole-based antioxidant, an oligomer type having a benzotriazole structure, a compound of a polymer type, or the like can be used.

Examples of the benzophenone-based antioxidant include 2-hydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, and 2-hydroxy-4-n-octoxybenzophenone. , 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2'dihydroxy-4-methoxybenzophenone, 2,2'dihydroxy-4,4'dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-5 sulfo Benzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4-chlorobenzophenone, and the like. Other oligomer types having a benzophenone structure, a compound of a polymer type, and the like can also be used.

Examples of the triazine-based antioxidant include 2,4-bis(allyl)-6-(2-hydroxyphenyl) 1,3,5-triazine. Other oligomer types having a triazine structure, a compound of a polymer type, and the like can also be used.

Examples of the salicylate-based antioxidant include a salicylic acid phenyl group, a salicylic acid-p-octyl phenyl ester, and a salicylic acid-terminated tertiary phenylphenyl group. Other oligomer types having a salicylate structure, a compound of a polymer type, and the like can also be used.

As the antioxidant, a sulfur-based antioxidant or a phenol-based antioxidant is preferred. Among them, the stability from the organic solvent is more favorable, and it is not easy to be defective (that is, the defect suppressing property is more excellent). From the viewpoint of being selected from dibutylhydroxytoluene, hydroquinone, 3,3'- Di(dodecyl) thiodipropionate, di(octadecyl) 3,3'-thiodipropionate, di(tetradecyl) 3,3'thiodipropionate , 4,4'-butylidene bis-(6-tris-butyl-3-methylphenol), and 2,2'-methylenebis-(4-ethyl-6-tertiary butylphenol) At least one of the constituent groups is further preferable.

These antioxidants can be used singly or in combination of two or more kinds at any ratio as needed.

The chelating agent is not particularly limited, and examples thereof include a carboxylic acid-based chelating agent, a phosphonic acid-based chelating agent, and a sulfonic acid-based chelating agent. Among them, a carboxylic acid-based chelating agent and a phosphonic acid-based chelating agent are preferred.

As the carboxylic acid-based chelating agent, a polyaminopolycarboxylic acid is preferred. The polyaminopolycarboxylic acid is a compound having a plurality of amine groups and a plurality of carboxyl groups. Examples of the polyaminopolycarboxylic acid include diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetrapropionic acid, triethylenetetraminehexaacetic acid, and 1,3-diamino-2-hydroxypropane-N. , N, N', N'-tetraacetic acid, propylene diamine tetraacetic acid, and ethylenediaminetetraacetic acid (EDTA). Among them, diethylenetriaminepentaacetic acid (DTPA) and ethylenediaminetetraacetic acid (EDTA) are preferred.

The phosphonic acid chelating agent is a chelating agent having a phosphonic acid group, and examples thereof include 9,10-dihydro-9-oxa-10-phosphinophen-10-oxide.

From the viewpoint of the fact that the stability of the organic solvent is further improved, and it is less likely to cause defects in the semiconductor device, among the above stabilizers, an antioxidant is preferred.

As the antioxidant, a boiling point of 150 to 400 ° C is preferred. Examples of the antioxidant having a boiling point in the range of 150 to 400 ° C include dibutylhydroxytoluene (265 ° C), hydroquinone (287 ° C), and 3,3'-thiodipropionic acid (fourteen). Alkyl)ester (347.7 ° C) and 2,2'-methylenebis-(4-ethyl-6-tributylphenol) (187.5 ° C) and the like. When a boiling point of 150 to 400 ° C is used as the antioxidant, the antioxidant is easily volatilized during the baking treatment step of the resist film. Therefore, when the purified organic solvent is applied to a photosensitive ray-sensitive or radiation-sensitive composition, it is possible to suppress defects in the semiconductor device caused by the antioxidant. Further, when the purified organic solvent is used as a pre-wet liquid, it is possible to suppress defects in the semiconductor device caused by the antioxidant.

[Application] The organic solvent after purification is used in the production of a semiconductor device, and specifically, it is used as at least one selected from the group consisting of a pre-wet liquid, a developing solution, and a solvent contained in a sensitizing ray-sensitive or radiation-sensitive composition. use. The pre-wet liquid is applied to a substrate for improving the coatability of the composition before the step of forming a photoresist film using a sensitizing ray-sensitive or radiation-sensitive composition. The developer is used for development of the resist film after exposure. The solvent (organic solvent) contained in the sensitizing ray-sensitive or radiation-sensitive composition (hereinafter also referred to as "resist composition") is used as a component such as a resin in the dissolved composition, and the resist is improved. Uses such as coatability of the composition. In the present specification, the resist film before exposure is referred to as a "resist film", and the resist film after exposure is simply referred to as "resist film".

Further, the purified organic solvent can be preferably used for other purposes than semiconductor devices, and can also be used as a developing solution or a rinsing liquid for a polyimide, a resist for a sensor, and a resist for a lens. use.

Further, the purified organic solvent can also be used for a solvent for medical use and a cleaning application, and can also be preferably used for cleaning containers, pipes, and substrates (for example, wafers, glass, etc.).

The refining device for an organic solvent of the present invention may further comprise a dehydrating member for removing moisture in the organic solvent. By reducing the amount of water in the organic solvent to reduce the water which is the cause of the watermark, it is advantageous in that the semiconductor device can be prevented from being defective, or the stability of the organic solvent after purification can be further improved. The position at which the dewatering member is disposed is not particularly limited, and can be disposed, for example, on the downstream side of the metal ion adsorbing member and the filter member. Examples of the dehydrating member include a dehydrated film, a water adsorbent insoluble in an organic solvent, an aeration replacing device using a dried inert gas, and a heating or vacuum heating device. When a dehydrated membrane is used, it is preferred to carry out membrane dehydration based on pervaporation (PV) or vapor permeation (VP). The dehydrated film is formed, for example, as a water permeable film module. Examples of the dehydrated film include a polymer material such as a polyimide, a cellulose or a polyvinyl alcohol, or a film made of an inorganic material such as zeolite. The water adsorbent is added to an organic solvent for use. Examples of the water adsorbent include zeolite, phosphorus pentoxide, tannin, calcium chloride, sodium sulfate, magnesium sulfate, anhydrous zinc chloride, fuming sulfuric acid, and soda lime.

The case where both the metal ion adsorption member 30 and the filter member 40 are provided in the refining device 100 is shown, but it is not limited to this. Specifically, the organic solvent purification device of the present invention may be a purification device having only one of a filter member and a metal ion adsorption member having a filter having a filter having a particle diameter of 20 nm or less.

Although the metal ion adsorption member 30 is provided with two metal ion adsorption filters in the refining device 100, the present invention is not limited thereto. Specifically, the metal ion adsorption member may include one metal ion adsorption filter, or may have three or more metal ion adsorption filters. When two or more metal ion adsorption members are provided, metal ions can be removed more effectively. Although the filter member 40 is provided with one filter in the refining device 100, the present invention is not limited thereto. Specifically, from the viewpoint of more effectively removing particulate impurities, it is preferred that the filter member has two or more filters.

In the refining device 100, the members are sequentially disposed so that the organic solvent sequentially passes through the first metal ion adsorption filter 32, the filter member 40, and the second metal ion adsorption filter 34. However, the present invention is not limited thereto. In the apparatus for purifying an organic solvent of the present invention, the arrangement order of the filter member and the metal ion adsorbing member can be appropriately set.

In the present invention, the metal ion adsorbing member and the filter member may respectively combine different members and/or the same member. At this time, in the first member, adsorption or filtration may be performed only once, or may be performed twice or more. When the different members are combined and adsorbed or filtered twice or more, the members may be of the same type or may be of different types, but different types are preferred. It is preferable that the apertures of the first member and the second member and at least one of the constituent materials are different. For example, with respect to filtration, it is preferred that the pore size to be filtered after the second time is the same as or smaller than the pore size of the first filtration. Further, the first filter and the second filter having different pore diameters within the above range can be combined. The aperture here can refer to the nominal value of the filter manufacturer. As a commercially available filter, for example, it can be used in various filters supplied by NIHON PALL LTD., Advantec Toyo Kaisha, Ltd., Nihon Entegris KK (old Nippon micro squirrel Co., Ltd.) or Kitz Micro Filter Corporation. select. Further, a "P-nylon filter (pore diameter: 0.02 μm, critical surface tension: 77 mN/m)" made of polyamine ("NIHON PALL LTD."), "PE/dust-free filtration" made of high-density polyethylene can also be used. (Polymeter 0.02 μm); (manufactured by NIHON PALL LTD.), and "PE/dust-free filter (pore size 0.01 μm)" made of high-density polyethylene; (manufactured by NIHON PALL LTD.).

Although not particularly limited, in addition to the viewpoint of obtaining the desired effect of the present invention more clearly, in view of suppressing an increase in particulate metal in the case of storing the purified organic solvent, in one aspect of the present invention, The relationship between the organic solvent used and the material of the filter used in the filtration is such that the combination of the following relationship is satisfied, that is, the Hansen Solubility Parameter (HSP) space derived from the material of the filter used in the filtration. When the interaction radius (R0) and the radius (Ra) of the sphere of the Hansen space derived from the liquid contained in the organic solvent, the relationship between Ra and R0 (Ra/R0) ≤ 1, and the It is preferred to filter the organic solvent in the filter material of the relationship. (Ra/R0) ≤ 0.98 is preferable, and (Ra/R0) ≤ 0.95 is more preferable. The lower limit is preferably 0.5 or more, more preferably 0.6 or more, and still more preferably 0.7 or more. Although the mechanism is not clear, if it is in this range, formation of a particulate metal or growth of a particulate metal at the time of long-term storage can be suppressed. The combination of the filters and the organic solvent is not particularly limited, and those described in the specification of the US Patent Application Publication No. 2016/0089622 are mentioned.

The second filter can use a filter formed of the same material as the above-described first filter. When the second filter having a smaller pore diameter than the first filter is used, the ratio of the pore diameter of the second filter to the pore diameter of the first filter (the pore diameter of the second filter / the pore diameter of the first filter) is 0.01 to 0.99. Preferably, 0.1 to 0.9 is more preferred, and 0.2 to 0.9 is further preferred. By setting the pore diameter of the second filter to the above range, it is possible to surely remove fine foreign matter mixed in the organic solvent.

Further, it is preferred that the member to be used is pretreated before the organic solvent of the present invention is treated. The liquid to be used in the pretreatment is not particularly limited, and if it is the organic solvent itself of the present invention, further purified, or diluted, the desired effect of the present invention can be remarkably obtained.

Although it is not particularly limited, when the adsorption or filtration is carried out, the upper limit of the temperature at the time of adsorption or filtration is preferably room temperature (25 ° C) or less, more preferably 23 ° C or less, and further preferably 20 ° C or less. . Further, the lower limit of the temperature at the time of adsorption or filtration is preferably 0 ° C or more, more preferably 5 ° C or more, and further preferably 10 ° C or more. In the filtration, it is particularly easy to remove particulate foreign matter or impurities, and when the temperature is raised at the above temperature, the amount of particulate foreign matter or impurities dissolved in the organic solvent is reduced, so that filtration is performed more efficiently.

In particular, from the viewpoint of adjusting the content of the metal component (metal impurity), it is preferred to carry out filtration at the above temperature. Although the mechanism is not clear, it is considered that the metal component (metal impurity) is mostly present in a particulate colloidal state. When the filtration is carried out at the above temperature, a part of the metal component (metal impurity) suspended in a colloidal state is aggregated, and the agglomerator can be effectively removed by filtration, so that it is considered that the content of the metal component (metal impurity) is easily adjusted to The prescribed amount.

The filtration pressure has an influence on the filtration accuracy, so that the pulsation of the pressure at the time of filtration is preferably as small as possible. In the method for purifying the organic solvent of the present invention, the filtration rate is not particularly limited, but from the viewpoint of more clearly obtaining the desired effect of the present invention, 1.0 L/min/m ² or more is preferable, and 0.75 L/min/ m ² or more is more preferred, 0.6L / min / m ² or more is further preferred. The filter is provided with a differential pressure that ensures filter performance (the filter is not broken), and when the value is large, the filtration speed can be increased by increasing the filtration pressure. That is, the upper limit of the filtration rate generally depends on the differential pressure of the filter, and is usually preferably 10.0 L/min/m ² or less.

In the method for purifying the organic solvent of the present invention, from the viewpoint of obtaining the desired effect of the present invention, the filtration pressure is preferably 0.001 to 1.0 MPa, more preferably 0.003 to 0.5 MPa, and further 0.005 to 0.3 MPa. good. In particular, when a filter having a small pore size is used, the amount of particulate foreign matter or impurities dissolved in an organic solvent can be effectively reduced by enumerating the pressure of filtration. When a filter having a pore diameter of less than 20 nm is used, a filtration pressure of 0.005 to 0.3 MPa is particularly preferable.

Further, when the pore size of the filtration membrane is reduced, the filtration rate is lowered. However, for example, by filtering a plurality of filters in which the same type of filtration membranes are mounted side by side to expand the filtration area and reduce the filtration pressure, the filtration can be compensated. The speed is falling.

[Method for Purifying Organic Solvent] <First Embodiment> A first embodiment of the method for purifying an organic solvent of the present invention (hereinafter simply referred to as "the purification method of the first embodiment") includes the following steps: a distillation step, Distilling the organic solvent containing the stabilizer to reduce the stabilizer in the organic solvent, setting the content of the stabilizer in the organic solvent to 0.1 to 30 ppm by mass; and purifying the step after the distillation step The organic solvent is purified by removing at least one of a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorbing member, and the method for purifying the organic solvent does not include removing the organic solvent by an organic impurity adsorbing member. An organic impurity removal step of organic impurities in the process. The purification method of the first embodiment can be carried out while circulating the organic solvent by using the above-described organic solvent purification device. Therefore, in the following description, the same functions as those of the respective members in the above-described organic solvent purification apparatus are given, and the description thereof will be omitted. According to the purification method of the first embodiment, the state in which the stability of the organic solvent is excellent can be maintained even after the purification. In the present invention, the organic solvent after purification refers to an organic solvent obtained by the method for purifying an organic solvent of the present invention. In addition, the organic solvent before purification is an organic solvent to be purified before the purification method of the organic solvent of the present invention.

(Distillation step) The purification method according to the first embodiment includes a distillation step of distilling an organic solvent containing a stabilizer to reduce the stabilizer in the organic solvent, and the stabilizer in the organic solvent. The content is set to be 0.1 to 30 ppm by mass. By this step, the stabilizer in the organic solvent is removed, and organic impurities other than the stabilizer in the organic solvent are also removed.

In the purification method of the first embodiment, the content of the stabilizer in the organic solvent (that is, the organic solvent before purification) before the distillation step is more than the content of the stabilizer contained in the organic solvent after the distillation step. Although it is not particularly limited, it is preferably more than 0.1 ppm by mass, more preferably more than 0.5 ppm by mass, and still more preferably 2 ppm by mass or more. Further, the content of the stabilizer in the organic solvent was measured by a GC-MS (Gas Chromatography Mass Spectrometry) apparatus.

In the purification method of the first embodiment, the content of the stabilizer in the organic solvent after the distillation step is 0.1 to 30 ppm by mass, preferably 0.5 to 30 ppm by mass, more preferably 1 to 20 ppm by mass, and 2 to 10 ppm. The mass ppm is further preferred. When the content of the stabilizer after the distillation step is within the above range, the stability of the organic solvent after purification is excellent, and defects in the semiconductor device can be suppressed. The method of setting the content of the stabilizer in the organic solvent after the distillation step is carried out, for example, by appropriately adjusting the distillation conditions (distillation temperature, number of distillations, distillation rate, etc.) depending on the type of the organic solvent and the stabilizer.

In the purification method of the first embodiment, the upper limit of the boiling point (normal boiling point) of the organic solvent is preferably 210 ° C or lower, more preferably 160 ° C or lower, further preferably 150 ° C or lower, and particularly preferably 145 ° C or lower. Good, below 140 °C is the best. The lower limit of the boiling point (normal boiling point) of the organic solvent is preferably 45 ° C or more, more preferably 100 ° C or more, and still more preferably 110 ° C or more. In the purification method of the first embodiment, the upper limit of the boiling point (standard boiling point) of the stabilizer (preferred antioxidant) is preferably 710 ° C or less, more preferably 600 ° C or less, and further less than 400 ° C. Good, below 350 °C is especially good. The lower limit of the boiling point (normal boiling point) of the stabilizer (preferred antioxidant) is preferably 180 ° C or more, more preferably more than 200 ° C, more preferably 220 ° C or more, and particularly preferably 240 ° C or more. For example, the above BHT has a boiling point of 265 °C. The distillation temperature is preferably 150 to 240 ° C, more preferably 160 to 230 ° C, and still more preferably 165 to 220 ° C.

Here, in the purification method of the first embodiment, the boiling point of the organic solvent is lower than the boiling point of the stabilizer, and the distillation temperature of the organic solvent in the distillation step is equal to or higher than the boiling point of the organic solvent, and is preferably lower than the boiling point of the stabilizer. In other words, the relationship (the boiling point of the organic solvent) ≤ (distillation temperature) < (the boiling point of the stabilizer) is satisfied. By the distillation step, the stabilizer in the organic solvent can be removed, but by satisfying the relationship (the boiling point of the organic solvent) ≤ (distillation temperature) < (the boiling point of the stabilizer), it is possible to more effectively separate and stabilize from the organic solvent. Therefore, it is easy to set the content of the stabilizer in the organic solvent within the above range. Further, the distillation temperature of the organic solvent in the distillation step is higher than the boiling point of the organic solvent, and is preferably lower than the boiling point of the stabilizer. In other words, the relationship (the boiling point of the organic solvent) < (distillation temperature) < (the boiling point of the stabilizer) is satisfied. By satisfying this relationship, the stabilizer can be further effectively separated from the organic solvent, and organic impurities other than the stabilizer can be efficiently separated from the organic solvent. In addition, when two or more kinds of organic solvents are used, the boiling point of the organic solvent having the highest content is used as a standard, and when the organic solvent having the highest content is two or more types, the one having the highest boiling point is used as a standard. When two or more kinds of stabilizers are contained, the boiling point of the stabilizer having the highest content is used as a standard, and when the stabilizer having the highest content is two or more types, the one having the lower boiling point is used as a standard.

The distillation step can be carried out under any atmosphere of a large pressure or under reduced pressure. The distillation rate is not particularly limited, and is usually 1 to 50 liters (L) per hour, more preferably 1 to 30 L/hour, more preferably 3 to 20 L/hour, and particularly preferably 5 to 10 L/hour. In the purification method of the first embodiment, the distillation step may be carried out once or several times.

(Purification Step) The purification method according to the first embodiment includes a purification step of purifying the organic solvent by at least one of the filter member and the metal ion adsorption member after the distillation step. By using a filter member, it is possible to remove particulate impurities (especially inorganic impurities such as metal particles) contained in the organic solvent before purification, and to remove the organic solvent before purification by using the metal ion adsorption member. Metal ions. Therefore, according to the treatment step, the amount of particulate impurities and/or the content of metal ions contained in the organic solvent after purification can be reduced. When an organic solvent having such a reduced amount of particulate impurities and/or a content of metal ions is used, it is possible to suppress defects in the semiconductor device.

It is preferred that the purification step is carried out twice or more. Thereby, the amount of particulate impurities and/or the content of metal ions contained in the organic solvent after purification can be further reduced. When the above-described organic solvent purification apparatus 100 is used, the number of times of the purification step in which the organic solvent flowing out of the tank 10 passes through the filter member 40 and/or the metal ion adsorption member 30 and is recovered by the tank 10 is once (corresponding to an organic solvent) Number of cycles). In the example of FIG. 1, the organic solvent that has flowed out of the tank 10 has three filters including one filter provided in the filter member 40 and two metal ion adsorption filters included in the metal ion adsorption member 30. It is recycled by the tank 10. In this case, the number of times of the purification step is three (corresponding to the number of passes of the organic solvent through the filter provided in the filter member 40 and the metal ion adsorption filter provided in the metal ion adsorption member 30). That is, the number of times of the refining step corresponds to the product of the number of cycles of the organic solvent and the number of passes of each of the above filters.

In the refining step, it is more preferable to carry out the use of the above-described filter member and the above-described metal ion adsorbing member from the viewpoint of further suppressing the occurrence of defects in the semiconductor device.

The amount of the particulate-like impurities in the organic solvent after the purification is preferably 100 or less in 1 mL of the organic solvent after purification, more preferably 50 or less, more preferably 10 or less, and particularly preferably 0. Thereby, it is possible to suppress the occurrence of defects in the semiconductor device. Further, the details of the particulate impurities are as described above. The amount of particulate impurities present in the purified organic solvent can be measured in a liquid phase by using a commercially available measuring device in a light scattering liquid particle measuring method using a laser as a light source.

<Metal ions selected from the group consisting of Fe, Cr, Ni, and Pb> The present inventors have studied and found that the specific metal ions contained in the organic solvent are particularly relevant to the defect performance. Specifically, the content of the metal ion selected from the group consisting of Fe, Cr, Ni, and Pb in the purified organic solvent is preferably 0.1 to 1000 ppm by mass. Here, when two or more kinds of the above metal ions are contained in the organic solvent after purification, the content of the metal ions indicates the total content of two or more kinds of metal ions. The metal component may be present to some extent in the raw material component used in the production of the organic solvent, and may be mixed into the organic solvent by these. When the content of the metal ions of the group consisting of Fe, Cr, Ni, and Pb in the organic solvent is 1000 mass ppm or less, the defect suppressing property is further excellent. On the other hand, when the content of the metal ion selected from the group consisting of Fe, Cr, Ni, and Pb is estimated to be less, the inventors have confirmed that the defect is suppressed when the content is 0.1 mass or more. More excellent. The reason for this is not clear, but it can be inferred that the more the metal ions in the organic solvent are in a state of aggregation, the easier it is to remove from the substrate. When the organic solvent is used as a developing solution, the metal ions derived from the developer may adhere to the surface of the substrate to cause defects. On the other hand, when the content of the metal ions is 0.1 mass or more, a large amount of metal ions are aggregated, and thus can be effectively removed from the substrate. On the other hand, when the metal ion content is less than 0.1 mass ppt, the metal ions are easily released in the organic solvent, and tend to remain on the surface of the substrate. The content of metal ions in the organic solvent is determined by SP-ICP-MS (Single Particle-Inductively Coupled Plasma-Mass Spectrometry). The amount of the metal element present in the solution can be measured by dividing the amount of the metal element present in the solution into a metal ion (ionic metal) and a metal particle (nonionic metal) according to the measurement by the SP-ICP-MS method. The metal particles (nonionic metal) are components which are not dissolved in a solution (organic solvent) but are present as a solid. The content of the metal ion in the organic solvent is specifically determined by using a device based on NexION 350 (product name, manufactured by PerkinElmer, Inc.) and using software used in the SP-ICP-MS method. Further, in the organic solvent after purification, the content of metal ions other than the above is also preferably small.

The purification method of the first embodiment does not have an organic impurity removal step. Thereby, the stability of the organic solvent after purification is excellent.

The content of the organic impurities in the organic solvent after purification is preferably 1 ppm by mass to 10,500 ppm by mass, more preferably 1 ppm by mass to 5,000 ppm by mass, still more preferably 1 ppm by mass to 3,000 ppm by mass, and further preferably 1 ppm by mass. 1000 mass ppm is particularly good. Specific examples of the organic impurities are as described above. The content of organic impurities was measured by a GC-MS (Gas Chromatography Mass Spectrometry) apparatus.

The purification method of the first embodiment may further include a dehydration step for removing moisture in the organic solvent. The dehydration step can be carried out by the above-described dewatering member. The dehydration step is not limited thereto, and can be carried out, for example, after the above-described purification step. The content of water in the organic solvent after purification is preferably 0.1 to 1.5% by mass, more preferably 0.1 to 1.0% by mass, still more preferably 0.1 to 0.5% by mass. The content of water in the organic solvent is measured by a Karl Fischer moisture measurement method (Coulometric titration method) as a measurement principle, and is measured by the method described in the column of Examples to be described later.

[Electrification Step] The method for purifying the organic solvent of the first embodiment may further have a step of removing electricity. In addition, at least one type (hereinafter referred to as "refined product or the like") which is a group consisting of a raw material selected from an organic solvent, an organic solvent before purification, and an organic solvent after purification (hereinafter referred to as "a purified product or the like") is used to reduce the amount of the purified product. The step of 帯 electric potential. The method of removing electricity is not particularly limited, and a known method of removing electricity can be used. The method of removing electricity includes, for example, a method of bringing the purified product or the like into contact with a conductive material. The contact time between the purified product and the like and the conductive material is preferably 0.001 to 60 seconds, more preferably 0.001 to 1 second, and still more preferably 0.01 to 0.1 second. Examples of the conductive material include stainless steel, gold, platinum, diamond, and glassy carbon. For example, a method of bringing a purified material or the like into contact with a conductive material, for example, a method in which a grounded net made of a conductive material is placed inside a pipe, and a purified product or the like is turned on.

The above-described static elimination step is preferably carried out before at least one of the distillation step and the purification step. For example, it is preferred to carry out the static elimination step before supplying the organic solvent to the above-mentioned can or the like. Thereby, impurities from a container or the like can be prevented from being mixed into the purified product or the like.

(Second embodiment) The second embodiment of the method for purifying an organic solvent of the present invention (hereinafter also referred to simply as "the purification method of the second embodiment") includes a distillation step for organic substances which do not substantially contain a stabilizer. a solvent is distilled; a stabilizer addition step, after the above-described distillation step, a stabilizer is added to the organic solvent so that the content of the stabilizer in the organic solvent is 0.1 to 30 ppm by mass; and a refining step in the stabilizer After the addition step, the organic solvent is purified by using at least one of a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorbing member, and the method for purifying the organic solvent does not include an organic impurity adsorbing member. An organic impurity removing step of removing organic impurities in the above organic solvent. In the purification method of the second embodiment, the content of the stabilizer in the organic solvent before purification, the details of the distillation step, and the steps including the step of adding the stabilizer are different from those of the purification method of the first embodiment. Other than this, it is the same as that of the first embodiment, and therefore only differences from the first embodiment will be described below.

(Distillation Step) The distillation step in the purification method of the second embodiment is a step of distilling an organic solvent which does not substantially contain a stabilizer. Thereby, organic impurities in the above organic solvent can be removed. In the purification method of the second embodiment, as the organic solvent before the distillation step (that is, the organic solvent before purification), an organic solvent which does not substantially contain a stabilizer is used. In the present invention, "actually no stabilizer" means less than 0.1 mass ppm. Further, the content of the stabilizer in the organic solvent was measured by a GC-MS (Gas Chromatography Mass Spectrometry) apparatus.

In the purification method of the second embodiment, the upper limit of the boiling point (normal boiling point) of the organic solvent is preferably 210 ° C or lower, more preferably 160 ° C or lower, further preferably 150 ° C or lower, and particularly preferably 145 ° C or lower. Good, below 140 °C is the best. The lower limit of the boiling point (normal boiling point) of the organic solvent is preferably 45 ° C or more, more preferably 100 ° C or more, and still more preferably 110 ° C or more. The distillation temperature is preferably 150 to 240 ° C, more preferably 160 to 230 ° C, and still more preferably 165 to 220 ° C.

In the purification method of the second embodiment, the distillation temperature of the organic solvent in the distillation step is preferably at least the boiling point of the organic solvent, and more preferably higher than the boiling point of the organic solvent. Thereby, organic impurities can be more effectively separated from the organic solvent.

The distillation step can be carried out under any atmosphere of a large pressure or under reduced pressure. The distillation rate is not particularly limited, and is usually 1 to 50 liters (L) per hour, more preferably 1 to 30 L/hour, more preferably 3 to 20 L/hour, and particularly preferably 5 to 10 L/hour. In the purification method of the second embodiment, the distillation step may be carried out once or several times.

(Stabilizer Addition Step) In the purification method of the second embodiment, the content of the stabilizer in the organic solvent is 0.1 to 30 ppm by mass after the distillation step and before the purification step (refer to the first embodiment). A step of adding a stabilizer to an organic solvent. In this step, the stabilizer is added so that the content of the stabilizer in the organic solvent is 0.1 to 30 ppm by mass. However, it is preferable to add the stabilizer so as to be 0.5 to 30 ppm by mass, so as to be 1 to 20 ppm by mass. It is more preferable to add a stabilizer in a manner, and it is further preferable to add a stabilizer so as to be 2 to 10 ppm by mass. Thereby, the stability of the organic solvent after purification is excellent, and it is also possible to suppress the occurrence of defects in the semiconductor device. The method of adding the stabilizer is not particularly limited, and can be carried out by a known method.

[Container (Container Container)] The organic solvent after purification can be stored in a container, stored, and used in a range where corrosion or the like is not a problem. When it is used as a container for semiconductor use, it is preferable that the degree of cleanliness in the container is high and the amount of impurities eluted is small. Specific examples of the container that can be used include the "Clean Bottle" series manufactured by AICELLO CHEMICAL CO., LTD., and the "Pure Bottle" manufactured by KODAMA PLASTICS Co., Ltd., but are not limited thereto. It is preferable that the inner wall of the container (the liquid contact portion that is in contact with the organic solvent in the container) is formed of a non-metal material. As a non-metallic material, selected from polyethylene resin, polypropylene resin, polyethylene-polypropylene resin, polytetrafluoroethylene resin (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene Ethylene-hexafluoropropylene copolymer resin (FEP), tetrafluoroethylene-ethylene copolymer resin (ETFE), chlorotrifluoroethylene-ethylene copolymer resin (ECTFE), polyvinylidene fluoride resin (PVDF), chlorotrifluoroethylene copolymerization At least one of a group consisting of a resin (PCTFE) and a polyvinyl fluoride resin (PVF) is more preferable. In particular, when the container having the inner wall of the fluorine-based resin is used, the oligomerization of ethylene or propylene can be suppressed as compared with the case where the inner wall is a container of a polyethylene resin, a polypropylene resin or a polyethylene-polypropylene resin. The substance dissolves out the occurrence of this bad condition. Specific examples of the container in which the inner wall is a fluorine-based resin include a Fluoro Pure PFA composite cylinder manufactured by Entegris, Inc., and the like. Further, it is also possible to use the fourth page of the Japanese Patent Publication No. 3-502677, the third page of the International Publication No. 2004/016526, and the pages 9 and 16 of the International Publication No. 99/46309. The container described in . Further, when it is set as the inner wall of a non-metal material, it is preferable to suppress elution of the organic component in the non-metal material into the organic solvent.

Further, in addition to the above-mentioned non-metallic material, quartz or a metal material (a metal material which is electrolytically ground, in other words, a metal material which is subjected to electrolytic polishing) may be preferably used in the inner wall of the container. The metal material (especially the metal material used for the production of the metal material to be electrolytically polished) is preferably one containing more than 25% by mass of chromium based on the total mass of the metal material, and examples thereof include stainless steel. The content of chromium in the metal material is preferably 30% by mass or more based on the total mass of the metal material. Further, the upper limit thereof is not particularly limited, but is usually preferably 90% by mass or less.

Stainless steel is not particularly limited, and a known stainless steel can be used. Among them, an alloy containing 8% by mass or more of nickel is preferable, and an austenitic stainless steel containing 8% by mass or more of nickel is more preferable. Examples of the austenitic stainless steel include SUS (Steel Use Stainless) 304 (Ni content: 8 mass%, Cr content: 18% by mass), SUS304L (Ni content: 9% by mass, and Cr content: 18% by mass), and SUS316 (Ni). The content is 10% by mass, the Cr content is 16% by mass, and SUS316L (Ni content: 12% by mass, Cr content: 16% by mass).

The method of electrolytically polishing the metal material is not particularly limited, and a known method can be used. For example, the methods described in paragraphs [0011] to [0014] of JP-A-2015-227501, and paragraphs [0036] to [0042] of JP-A-2008-264929 can be used.

It can be inferred that the metal material is made by electrolytic polishing, and the content of chromium in the passivation layer on the surface becomes larger than the content of chromium in the mother phase. Therefore, it is estimated that the inner wall coated with the metal material to be electrolytically polished is less likely to flow out of the metal component into the organic solvent, so that an organic solvent having a reduced metal component (metal impurity) can be obtained. In addition, polishing of the metal material is preferred. The method of polishing is not particularly limited, and a known method can be used. The size of the abrasive grains to be used for fine polishing is not particularly limited, but from the viewpoint that the unevenness of the surface of the metal material is likely to be smaller, #400 or less is preferable. In addition, polishing is preferably performed before electrolytic polishing. In addition, the metal material may be subjected to one or a combination of two or more types of polishing, pickling, and magnetic fluid polishing in a plurality of stages, such as changing the size of the abrasive grains.

In the present invention, the container having the above-described container and the purified organic solvent contained in the container may be referred to as a solution container.

It is preferred that the containers are cleaned inside before filling the purified organic solvent. As the liquid to be cleaned, the effect of the present invention can be remarkably obtained by diluting the purified organic solvent itself or the purified organic solvent. The purified organic solvent can be transported and stored in a container such as a gallon bottle or a coated bottle. The gallon bottle can be used for glass materials or other.

For the purpose of preventing the change of the components in the organic solvent during storage, the inside of the container may be replaced with an inert gas (nitrogen or argon or the like) having a purity of 99.99995 vol% or more. In particular, a gas having a small water content is preferred. Further, it may be normal temperature during transportation and storage, but the temperature may be controlled within a range of -20 ° C to 20 ° C in order to prevent deterioration.

[Clean room] It is preferable to carry out the operation, the treatment analysis, and the measurement including the purification of the organic solvent, the opening and/or cleaning of the storage container, the filling of the organic solvent after purification, and the measurement in the clean room. It is preferred that the clean room meets the 14644-1 clean room reference. It is preferable to satisfy one of ISO (International Standardization Organization) level 1, ISO level 2, ISO level 3, and ISO level 4, and it is more preferable to satisfy ISO level 1 or ISO level 2, and it is further preferable to satisfy ISO level 1. [Examples]

Hereinafter, the present invention will be described in detail by way of examples. However, the invention is not limited thereto. In addition, "%", "ppt", and "ppm" are quality standards unless otherwise specified.

[Preparation of Organic Solvent Before Purification] In the purification of the organic solvents of the examples and the comparative examples, the following organic solvents were prepared. As the raw material used in the production of the organic solvent, a high purity grade of 99% by mass or more is used. Using the raw materials thus obtained, each organic solvent was produced in accordance with a known method, and each of the obtained organic solvents (organic solvent before purification) was used in the following purification step. Further, in the production of an organic solvent, stabilizers shown in the tables described later are used. In addition, the organic solvent before purification in the table to be described later is the same type of organic solvent, but the content of organic impurities or the like is different, which is due to the difference in the production method of the organic solvent and the batch number of the raw material of the organic solvent. And so on. (Type of organic solvent) ・ Butyl acetate (nBA, boiling point 126 ° C) ・ Propylene glycol monomethyl ether (PGME, boiling point 120 ° C) ・ Propylene glycol monoethyl ether (PGEE, boiling point 133 ° C) ・ Propylene glycol monopropyl ether (PGPE, boiling point 149 °C) ・Propylene glycol monomethyl ether acetate (PGMEA, boiling point 146 ° C) ・Ethyl lactate (EL, boiling point 155 ° C) ・γ-butyrolactone (γ-BL, boiling point 204 ° C) ・Cyclopentanone (CyPe, Boiling point: 49 ° C) ・Cyclohexanone (CyHe, boiling point 155.6 ° C) ・ 4-methyl-2-pentanol (MIBC, boiling point 131.6 ° C) (stabilizer) ・ Dibutylhydroxytoluene (BHT, boiling point 265 ° C) Hydroquinone (HQ, boiling point 287 ° C) ・3,3'-di(dodecyl) thiodipropionate (DLTP, boiling point 562.9 ° C) ・3,3'-thiodipropionic acid II ( Octadecyl) ester (DSTP, boiling point 704.8 ° C) ・4,4'-butylene bis(6-tris-butyl-3-methylphenol) (BFN, boiling point 475 ° C) ・2,2'-Asia Methyl bis-(4-ethyl-6-tributyl phenol) (MBF, boiling point 187.5 ° C) Further, the boiling points of the organic solvent and the stabilizer described in parentheses are standard boiling points.

[Examples 1-1 to 1-28, Comparative Example 1-1] Next, purification of the prepared organic solvent was carried out. Specifically, in the purification of the organic solvent, a device in which the "dewatering member" is connected to the downstream side of the second metal ion adsorption filter 34 of the organic solvent purification device 100 of FIG. 1 is used. Among them, in Example 1-27, a device in which the dewatering member was removed (that is, the refining device 100 itself of the organic solvent of Fig. 1) was used. In Comparative Example 1-1, an apparatus in which an "organic impurity adsorbing member" and a "dehydrating member" were sequentially attached to the downstream side of the second metal ion adsorbing filter 34 of the organic solvent purification apparatus 100 of FIG. Further, in Example 1-26, a predetermined amount of a stabilizer was added after the distillation step and before the purification step. Here, in the refining apparatus 100 for organic solvents of FIG. 1 used in the column of the embodiment, the tank 10 is coated with PTFE using a liquid contact portion of stainless steel. Further, the pump 20 is coated with PTFE using a liquid contact portion. Further, the supply pipe 60 uses a PFA pipe having an outer diameter of 12 mm. Further, in the distillation section 50, a plate type distillation column made of SUS316 (plate number: 10) was used. In the first metal ion adsorption filter 32 and the second metal ion adsorption filter 34, 15 nm IEX PTFE (a filter made of PTFE having a pore diameter of 15 nm having a sulfonic group on the surface of the substrate) manufactured by Entegris, Inc. was used. Further, as the filter member 40, 12 nm PTFE (a filter made of PTFE having a particle diameter of 12 nm) manufactured by Entegris, Inc. was used. In addition, the organic impurity adsorbing member 50 is a filter that adheres the activated carbon described in Japanese Laid-Open Patent Publication No. 2013-150979 to a nonwoven fabric. Then, after the respective organic solvents described in the first table are filled in the tank 10, the organic solvent is circulated once in the direction of the arrow in FIG. Thus, the purified organic solvents of Examples 1-1 to 1-28 and Comparative Example 1-1 were obtained. Further, the distillation conditions are shown in Table 1.

<Measurement of Content and Evaluation Test> Measurement of the content of each component and various evaluation tests were carried out using an organic solvent before and after purification. Here, the following measurement and evaluation tests are all performed in a clean room at a level of ISO 2 or less. In order to improve the measurement accuracy, in the measurement of each component, when it is below the detection limit in the normal measurement, it is measured by concentration in a volume ratio of 1/100, and is converted into the content of the organic solvent before concentration. The calculation of the content was carried out.

(Measurement of Content of Organic Impurity) The content of organic impurities (content relative to the total mass of the organic solvent) in each organic solvent was measured using an organic solvent before and after purification. GC-MS (product name "GCMS-2020", manufactured by Shimadzu Corporation) (analytical method based on area percentage method) was used for the measurement.

(Measurement of Content of Stabilizer) The content of the stabilizer (content relative to the total mass of the organic solvent) in each organic solvent was measured using an organic solvent before and after purification. GC-MS (product name "GCMS-2020", manufactured by Shimadzu Corporation) (analytical method based on area percentage method) was used for the measurement.

(Measurement of Water Content) The content of water in each organic solvent was measured using an organic solvent before and after purification. A Karl Fischer moisture meter (product name "MKC-710M", manufactured by KYOTO ELECTRONICS MANUFACTURING CO., LTD., Karl Fischer Coulometric titration) (analytical method based on area percentage method) was used for the measurement.

(Measurement of Content of Metal Ions) The content of metal ions (Fe, Cr, Ni, and Pb) in the organic solvent before and after purification was measured. Specifically, an organic solvent was used and NexION 350S (trade name, manufactured by PerkinElmer, Inc.) was used and carried out by SP-ICP-MS method. The measurement results are shown in the first table. The specific measurement conditions based on the SP-ICP-MS method are as follows. Further, the amount of the metal ion in the organic solvent used for the measurement was calculated by measuring the amount of detection with respect to the peak intensity of the standard solution of a known concentration and converting it into the mass of the metal ion. ((Measurement conditions)) ・The standard material was prepared by measuring ultra-pure water in a clean glass container, and the concentration of the metal ion to be measured was 1 mass ppt, and then treated with an ultrasonic cleaner for 30 minutes. The solution thus obtained was used as a standard substance for measuring the transport efficiency.・Used device manufacturer: PerkinElmer Type: NexION350S ・The measurement method used a PFA coaxial atomizer, a quartz cyclone spray chamber, and a quartz inner diameter 1 mm torch ejector. The measurement target solution was approximately 0.2 mL/min. Aspiration was performed. The ammonia-based cleaning was carried out with an oxygen addition amount of 0.1 L/min and a plasma output of 1600 W. The time decomposition energy was analyzed for 50 μs.・Software The content of metal components is measured using the following analysis software supplied with the manufacturer. Nanoparticle analysis "SP-ICP-MS" uses the Syngistix nano application module.

(Number of coarse particles) The number of coarse particles in the organic solvent before and after the purification was measured. Further, when the above-mentioned measurement of the number of coarse particles was carried out, it was allowed to stand at room temperature for one day after the preparation, and then a light scattering type liquid particle counter (RION Co., Ltd., model: KS-, was used according to the dynamic light scattering method). 18F, light source: semiconductor laser excited solid laser (wavelength 532nm, rated output 500mW), flow rate: 10mL / min), 5 times the count of 100nm or larger coarse particles contained in 1mL, the average value is taken as Measurement value. Further, the above-described light scattering liquid particle counter is used after being calibrated with PSL (Polystyrene Latex) standard particle liquid.

(Evaluation Test of Defects) Particles having a diameter of 19 nm or more present on the surface of a cerium oxide film substrate having a diameter of 300 mm were measured by a wafer upper surface detecting device (SP-5; manufactured by KLA-Tencor Corporation) (hereinafter, Called "defect".) Number. Then, the bare ruthenium substrate was placed on a rotary discharge device, and each of the purified organic solvents of the examples or the comparative examples was discharged to the surface of the same ruthenium oxide film substrate at a flow rate of 1.5 L/min. Thereafter, spin drying of the wafer was performed. With respect to the obtained dried wafer, the above-described apparatus (SP-5) was used again to measure the number of defects existing on the surface of the bare substrate, and the difference from the initial value was defined as the number of defects. The number of defects obtained was evaluated based on the following criteria. In the following criteria, when the evaluation is "D" or more, the ability to suppress defects required as an organic solvent for a semiconductor device is achieved. "A": the number of defects is 200 or less "B": the number of defects exceeds 200 and is 500 or less "C": the number of defects exceeds 500 and is 1000 or less "D": the number of defects exceeds 1000 and is 1500 or less "E": The number of defects exceeds 1500

(Evaluation Test of Stability) Each of the purified organic solvents of the examples and the comparative examples was stored at 45 ° C for 100 days. The decomposition rate was calculated from the ratio of NMR peaks by a nuclear magnetic resonance (NMR) apparatus (product name "NMR spectrometer Z (JNM-ECZR)" manufactured by JEOL RESONANCE Inc.). A: The decomposition rate is 1% or less B: The decomposition rate exceeds 1% and is 3% or less C: The decomposition rate exceeds 3% and is 5% or less D: The decomposition rate exceeds 5% and is 8% or less E: The decomposition rate exceeds 8 %

<Evaluation Results> The above evaluation results are shown in Table 1. In addition, in the column of Example 1-26 of the first table, "Organic solvent before purification (after distillation)", the content of each component and the number of coarse particles were measured after distillation and after adding a stabilizer.

[Table 1]

As shown in the first table, the content of the stabilizer in the organic solvent after the distillation step is in the range of 0.1 to 30 ppm by mass, and it is shown that an organic solvent excellent in stability can be obtained by the step of removing the organic impurities ( Examples 1-1 to 1-28). On the other hand, when the organic impurity removal step is performed, the content of the stabilizer in the organic solvent after purification becomes too small, and the stability is lowered. (Comparative Example 1-1).

[Examples 2-1 to 2-8, Comparative Example 2-1] In Examples 2-1 to 2-8 and Comparative Example 2-1, the filter member 40 was not used. Specifically, in the examples 2-1 to 2-8, a device in which a "dewatering member" is connected to the downstream side of the second metal ion adsorption filter 34 of the organic solvent purification device 100 of Fig. 1 is used, and The filter member 40 is removed. Further, in Comparative Example 2-1, the filter member 40 of the refining device 100 for removing the organic solvent of Fig. 1 was removed, and "organic impurity adsorption" was sequentially installed on the downstream side of the second metal ion adsorption filter 34. Components" and "dewatering members". Further, as the second metal ion adsorption filter 34, 10 nm IEX PTFE (a filter made of PTFE having a pore diameter of 10 nm having a sulfo group on the surface of the substrate) manufactured by Entegris, Inc. was used. Further, in Example 2-8, a predetermined amount of a stabilizer was added after the distillation step and before the purification step. In addition to the above, the same members as those of Examples 1-1 to 1-28 and Comparative Example 1-1 were used, and the organic solvent was purified by the same operation method, and the content of each component was measured and each Evaluation test. The measurement of the content of each component and each evaluation test were also carried out in the same manner as in Examples 1-1 to 1-28 and Comparative Example 1-1. The evaluation results are shown in the second table. In addition, in the column of Example 2-8 of the second table, "Organic solvent before purification (after distillation)", the content of each component and the number of coarse particles were measured after distillation and after adding a stabilizer. .

[Table 2]

As shown in the second table, in the examples 2-1 to 2-8 and the comparative example 2-1, since the filter member was not used, the number of coarse particles contained in the organic solvent after purification was large, and The tendency was the same as that of Example 1-1 to Example 1-28 and Comparative Example 1-1.

[Examples 3-1 to 3-9, Comparative Example 3-1] In Examples 3-1 to 3-9 and Comparative Example 3-1, a metal ion adsorbing member was not used. Specifically, in the examples 3-1 to 3-9, the metal ion adsorbing member 30 of the refining device 100 of the organic solvent of FIG. 1 was removed, and the number of filters of the filter member 40 was set to Two, and a "dehydration member" is attached to the downstream side of the filter member 40 which has two filters. In the comparative example 3-1, the metal ion adsorption member 30 of the refining device 100 of the organic solvent of FIG. 1 is removed, and the number of filters of the filter member 40 is two, and The "organic impurity adsorbing member" and the "dewatering member" are sequentially attached to the downstream side of the filter member 40 of the two filters. Further, in the two filters of the filter member 40, 15 nm PTFE manufactured by Entegris, Inc. (a filter having a particle size of 15 nm removed by PTFE) was used on the upstream side, and Entegris, Inc. was used on the downstream side. 12 nm PTFE (filter made of PTFE with a particle size of 12 nm removed). Further, in Examples 3-8 and 3-9, a predetermined amount of a stabilizer was added after the distillation step and before the purification step. In addition to the above, the same members as those of Examples 1-1 to 1-28 and Comparative Example 1-1 were used, and the organic solvent was purified by the same operation method, and the content of each component was measured and each Evaluation test. The measurement of the content of each component and each evaluation test were also carried out in the same manner as in Examples 1-1 to 1-28 and Comparative Example 1-1. The evaluation results are shown in Table 3. In addition, in the column of Example 3-8 of the third table and the "organic solvent before purification (after distillation)" of Example 3-9, the content of each component and the number of coarse particles were distilled and a stabilizer was added. The measurement was carried out afterwards.

[table 3]

As shown in the third table, in Examples 3-1 to 3-9 and Comparative Example 3-1, since the metal ion adsorbing member was not used in the purification, a large amount of metal ions were contained in the organic solvent after purification. The same tendency as in Example 1-1 to Example 1-28 and Comparative Example 1-1 was exhibited.

[Examples 4-1 to 4-5] In Examples 4-1 to 4-5, the number of cycles of the organic solvent was changed to 3, 5, 7, 10, and 12 times, respectively. The organic solvent was purified in the same manner as in Example 1-1, and the content of each component was measured and each evaluation test was performed. The measurement of the content of each component and each evaluation test were also carried out in the same manner as in Example 1-1. The evaluation results are shown in Table 4. In addition, in the fourth table, "<1" means less than 1.

[Table 4]

As shown in the fourth table, by performing the circulation of the plurality of organic solvents, metal ions and coarse particles can be removed more effectively (Examples 4-1 to 4-5), and the stability of the purified organic solvent is exhibited. Also excellent.

10‧‧‧ cans

20‧‧‧ pump

30‧‧‧Metal ion adsorption member

32‧‧‧1st metal ion adsorption filter

34‧‧‧Second metal ion adsorption filter

40‧‧‧Filter components

50‧‧‧Distillation Department

60‧‧‧Supply tube

100‧‧‧Refining device for organic solvents

Fig. 1 is a schematic view showing an embodiment of an apparatus for purifying an organic solvent of the present invention.

Claims (16)

A method for purifying an organic solvent, comprising: a distillation step of distilling an organic solvent containing a stabilizer to reduce the stabilizer in the organic solvent, and setting the content of the stabilizer in the organic solvent to 0.1 to 30 mass In the purification step, after the distillation step, the organic solvent is purified by using at least one of a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorption member, and the method for purifying the organic solvent is not An organic impurity removing step of removing organic impurities in the aforementioned organic solvent by an organic impurity adsorbing member is included. A method for purifying an organic solvent, comprising: a distillation step of distilling an organic solvent which does not substantially contain a stabilizer; and a stabilizer addition step, after the distillation step, the content of the stabilizer in the organic solvent is 0.1 to 30 a method of adding a stabilizer to the organic solvent in a mass ppm manner; and a purification step of using at least one of a filter member having a filter having a particle diameter of 20 nm or less and a metal ion adsorption member after the stabilizer addition step The organic solvent is purified by a member, and the method for purifying the organic solvent does not include an organic impurity removing step of removing organic impurities in the organic solvent by an organic impurity adsorbing member. The method for purifying an organic solvent according to claim 1, wherein a boiling point of the organic solvent is lower than a boiling point of the stabilizer, and a distillation temperature of the organic solvent in the distillation step is at least a boiling point of the organic solvent, and It is lower than the boiling point of the aforementioned stabilizer. The method for purifying an organic solvent according to the second aspect of the invention, wherein the distillation temperature of the organic solvent in the distillation step is at least the boiling point of the organic solvent. The method for purifying an organic solvent according to claim 3, wherein the distillation temperature is 150 to 240 °C. The method for purifying an organic solvent according to claim 1 or 2, wherein the metal ion adsorbing member includes a metal ion adsorption filter capable of ion exchange, and the metal ion adsorption filter has an acid group on the surface. The method for purifying an organic solvent according to claim 1 or 2, wherein the organic solvent is stored in a tank, and the refining step is carried out while circulating the organic solvent by a pump connected to the tank via a supply pipe. The liquid contact portion of the tank, the liquid contact portion of the supply pipe, and the liquid contact portion of the pump are each formed of a fluororesin. The method for purifying an organic solvent according to claim 1 or 2, wherein the purification step is carried out twice or more. The method for purifying an organic solvent according to claim 1 or 2, wherein the organic solvent is selected from the group consisting of n-butanol, 4-methyl-2-pentanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol. Propyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl acetate, isoamyl acetate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, and diisoamyl ether At least one organic solvent constituting the group. The method for purifying an organic solvent according to claim 1 or 2, wherein the organic solvent is used as a solvent selected from the group consisting of a pre-wet liquid, a developing solution, and a sensitizing ray-sensitive or radiation-sensitive composition. At least 1 use. An apparatus for purifying an organic solvent, comprising: a tank for storing an organic solvent; a pump connected to the tank to circulate the organic solvent; a distillation unit for distilling the organic solvent; and a filter for removing a particle diameter of 20 nm or less At least one of the filter member and the metal ion adsorbing member, the organic solvent purifying device does not have an organic impurity adsorbing member that removes organic impurities in the organic solvent. The apparatus for purifying an organic solvent according to claim 11, wherein the metal ion adsorbing member includes a metal ion adsorption filter capable of ion exchange, and the metal ion adsorption filter has an acid group on the surface. The apparatus for purifying an organic solvent according to claim 11 or 12, wherein the liquid contact portion of the tank and the liquid contact portion of the pump are each formed of a fluororesin. The apparatus for purifying an organic solvent according to claim 11 or 12, further comprising a supply tube that connects the tank and the pump, wherein the liquid contact portion of the supply tube is formed of a fluororesin. The apparatus for purifying an organic solvent according to claim 11 or 12, wherein the organic solvent is selected from the group consisting of n-butanol, 4-methyl-2-pentanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol. Propyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl acetate, isoamyl acetate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, and diisoamyl ether At least one organic solvent constituting the group. The apparatus for purifying an organic solvent according to claim 11 or 12, wherein the organic solvent is used as a solvent selected from the group consisting of a pre-wetting liquid, a developing solution, and a sensitizing ray-sensitive or radiation-sensitive composition. At least one use.