阅读说明：本技术 药液及药液的制造方法 (Chemical liquid and method for producing chemical liquid ) 是由 上村哲也 于 2019-01-07 设计创作，主要内容包括：本发明的课题在于提供一种即使在应用于利用EUV曝光进行的抗蚀剂步骤时也具有优异的缺陷抑制性能的药液。并且,本发明的另一课题在于提供一种药液的制造方法。本发明的药液含有：有机溶剂；及含有金属原子的含金属粒子,所述药液中,含金属粒子中粒径为0.5～17nm的金属纳米粒子在药液的每单位体积中的含有粒子数为1.0×10<Sup>1</Sup>～1.0×10<Sup>9</Sup>个/cm<Sup>3</Sup>。(The invention provides a chemical solution having excellent defect suppression performance even when applied to a resist step by EUV exposure. Another object of the present invention is to provide a method for producing a chemical solution. The liquid medicine of the present invention contains: an organic solvent; and metal-containing particles containing metal atoms, wherein the metal-containing particles are in the chemical solutionThe number of metal nanoparticles having a particle diameter of 0.5 to 17nm contained per unit volume of the drug solution is 1.0 × 10 1 ～1.0×10 9 Per cm 3 。)

1. A medical solution comprising:

an organic solvent; and

a metal-containing particle containing a metal atom,

said containsThe number of metal nanoparticles having a particle diameter of 0.5 to 17nm among the metal particles contained in the chemical solution per unit volume is 1.0 × 10¹Per cm³～1.0×10⁹Per cm³。

2. The medical solution according to claim 1, wherein,

the number-based particle size distribution of the metal-containing particles has a maximum value in at least one range selected from the group consisting of a range having a particle size of less than 5nm and a range having a particle size of more than 17 nm.

3. The medical solution according to claim 2, wherein,

the particle size distribution has a maximum value in a range of particle sizes of 0.5nm or more and less than 5 nm.

4. The chemical liquid according to any one of claims 1 to 3, which is used for manufacturing a semiconductor device.

5. The medical liquid according to any one of claims 1 to 4,

the metal nanoparticles comprise at least one selected from the group consisting of particles,

particles A containing a simple substance of the metal atom,

Particles B of an oxide containing the metal atom, and

and particles C containing a simple substance of the metal atom and an oxide of the metal atom.

6. The medical solution of claim 5, wherein,

a ratio of a number of contained particles of the particles a to a total number of contained particles of the particles B and the particles C per unit volume of the chemical solution is less than 1.0.

7. The medical solution according to claim 5 or 6,

the containing granuleThe ratio of the number of the subgroups is 1.0 × 10^-1The following.

8. The drug solution according to any one of claims 1 to 7, further comprising an organic compound having a boiling point of 300 ℃ or higher.

9. The medical solution of claim 8, wherein,

at least a part of the metal nanoparticles are particles U containing the organic compound.

10. The medical solution according to claim 8 or 9,

at least a part of the metal nanoparticles are particles U containing the organic compound and particles V not containing the organic compound,

the ratio of the number of particles contained in the particles U to the number of particles contained in the particles V per unit volume of the chemical solution is 1.0 × 10¹The above.

11. The medical liquid according to any one of claims 1 to 10,

the metal nanoparticles contain at least one selected from the group consisting of metal nanoparticles containing Pb atoms and metal nanoparticles containing Ti atoms.

12. The medical liquid according to any one of claims 1 to 11,

the metal nanoparticles include the metal nanoparticles containing Pb atoms and the metal nanoparticles containing Ti atoms.

13. The medical liquid according to any one of claims 1 to 12,

the ratio of the number of particles of Pb atom-containing metal nanoparticles to the number of particles of Ti atom-containing metal nanoparticles per unit volume of the chemical solution is 1.0 × 10^-3～2.0。

14. A method for producing a chemical solution according to any one of claims 1 to 13, comprising a filtration step of obtaining the chemical solution by filtering a purified product containing an organic solvent with a filter.

15. The method for producing chemical liquid according to claim 14,

the filtration step is a multistage filtration step in which the purified product is passed through at least 2 different types of filters selected from the group consisting of a material of the filter, a pore diameter, and a pore structure.

16. The method for producing chemical liquid according to claim 14 or 15,

in the case of using 1 filter, the pore diameter of the filter is 5nm or less, and in the case of using 2 or more filters, the pore diameter of the filter having the smallest pore diameter among the filters is 5nm or less.

Technical Field

The present invention relates to a liquid medicine and a method for producing the liquid medicine.

Background

In the case of manufacturing a semiconductor device by a wiring forming process including photolithography, a Chemical solution containing water and/or an organic solvent may be used as a pre-wetting solution, a resist solution (resist composition), a developing solution, a rinse solution, a stripping solution, a Chemical Mechanical Polishing (CMP) slurry, a cleaning solution after CMP, or a dilution thereof.

In recent years, the miniaturization of patterns has been progressing with the progress of photolithography. As a method for miniaturizing the pattern, a method of shortening the wavelength of an exposure light source can be used, and it has been attempted to form a pattern by using EUV (extreme ultraviolet) or the like having a further shorter wavelength as an exposure light source instead of ultraviolet light, KrF excimer laser, ArF excimer laser, or the like which have been used conventionally.

The pattern formation by EUV or the like is developed with a target of 10 to 15nm as the width of the resist pattern, and the chemical used in this step is required to have more excellent defect suppression performance.

As a method for producing a chemical solution for forming a resist pattern in the related art, patent document 1 describes "a method for producing a resist composition used in a semiconductor device production process, the method being characterized in that a production apparatus for a resist composition is cleaned with a cleaning solution, the cleaning solution is taken out from the production apparatus, spin-coated on an evaluation substrate, and cleaned until a change in defect density among defects having a size of 100nm or more before and after coating on the evaluation substrate becomes 0.2 pieces/cm²Thereafter, a resist composition was produced by the production apparatus. ", the above documents describe: as a result of ArF exposure using the chemical solution (resist composition) produced by this method, pattern defects and the like can be suppressed.

Prior art documents

Patent document

Patent document 1: japanese laid-open patent publication No. 2015-049395

Disclosure of Invention

Technical problem to be solved by the invention

The present inventors have found that defects may occur as a result of patterning by EUV exposure using a resist composition containing a chemical solution produced by the above-described production method.

Accordingly, an object of the present invention is to provide a chemical solution that is less likely to cause defects even when applied to a resist step using EUV exposure, in other words, has excellent defect suppression performance even when applied to a resist step using EUV exposure.

Another object of the present invention is to provide a method for producing a chemical solution.

Means for solving the technical problem

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by the following constitution.

[1]A chemical solution containing an organic solvent and metal-containing particles containing metal atoms, wherein the number of metal nanoparticles having a particle diameter of 0.5 to 17nm among the metal-containing particles contained in the chemical solution per unit volume is 1.0 × 10¹～1.0×10⁹Per cm³。

[2] The chemical solution according to [1], wherein the number-based particle size distribution of the metal-containing particles has a maximum value in at least one range selected from the group consisting of a range having a particle size of less than 5nm and a range having a particle size of more than 17 nm.

[3] The chemical according to [2], wherein the particle size distribution has a maximum value in a range of particle sizes of 0.5nm or more and less than 5 nm.

[4] The chemical liquid according to any one of [1] to [3], which is used for manufacturing a semiconductor device.

[5] The chemical liquid according to any one of [1] to [4], wherein the metal nanoparticles include at least one selected from the group consisting of particles A containing a simple metal atom, particles B containing an oxide of a metal atom, and particles C containing a simple metal atom and an oxide of a metal atom.

[6] The chemical liquid according to [5], wherein a ratio of a contained particle number of the particles A to a total contained particle number of the particles B and the contained particle number of the particles C per unit volume of the chemical liquid is less than 1.0.

[7]According to [5]]Or [6]]The chemical solution contains particles with a ratio of 1.0 × 10^-1The following.

[8] The drug solution according to any one of [1] to [7], further comprising an organic compound having a boiling point of 300 ℃ or higher.

[9] The chemical solution according to [8], wherein at least a part of the metal nanoparticles are particles U containing an organic compound.

[10]According to [8]Or [9]]The chemical solution, wherein at least a part of the metal nanoparticles are particles U containing an organic compound and particles V containing no organic compound, and the ratio of the number of particles U to the number of particles V per unit volume of the chemical solution is 1.0 × 10¹The above.

[11] The chemical liquid according to any one of [1] to [10], wherein the metal nanoparticles contain at least one selected from the group consisting of metal nanoparticles containing a Pb atom and metal nanoparticles containing a Ti atom.

[12] The liquid medicine according to any one of [1] to [11], wherein the metal nanoparticles include metal nanoparticles containing Pb atoms and metal nanoparticles containing Ti atoms.

[13]According to [1]To [12]]The chemical solution according to any one of the above, wherein the ratio of the number of particles of the metal nanoparticles containing Pb atoms to the number of particles of the metal nanoparticles containing Ti atoms per unit volume of the chemical solution is 1.0 × 10^-3～2.0。

[14] A method for producing a chemical solution according to any one of [1] to [13], the method comprising a filtration step of obtaining the chemical solution by filtering a purified product containing an organic solvent with a filter.

[15] The method for producing a chemical according to [14], wherein the filtration step is a multistage filtration step of passing the purified product through at least 2 or more different filters selected from the group consisting of a material of the filter, a pore diameter, and a pore structure.

[16] The method for producing a chemical solution according to [14] or [15], wherein the pore diameter of the filter is 5nm or less when 1 filter is used, and the pore diameter of the filter having the smallest pore diameter among the filters is 5nm or less when 2 or more filters are used.

Effects of the invention

According to the present invention, a chemical solution having excellent defect suppression performance even when applied to a resist process by EUV exposure can be provided. The present invention can also provide a method for producing a chemical solution.

Drawings

Fig. 1 is a schematic diagram showing a typical example of a purification apparatus capable of performing a multi-stage filtration process.

Detailed Description

The present invention will be described in detail below.

The following description of the constituent elements may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment.

In the present specification, the numerical range represented by "to" means a range in which the numerical values before and after "to" are included as the lower limit value and the upper limit value.

In the present invention, "ppm" means "parts-per-million (10)^-6): parts per million and "ppb" refers to "parts-per-billion (10)^-9): parts per billion and "ppt" refers to "parts-per-trillion (10)^-12): per millionth and ppq are referred to as "parts-per-quadratics (10)^-15): one giga ".

In the labeling of the group (atomic group) in the present invention, the label not labeled with substitution and unsubstituted includes not only a group having no substituent but also a group having a substituent within a range not impairing the effect of the present invention. For example, the term "hydrocarbon group" includes not only a hydrocarbon group having no substituent (unsubstituted hydrocarbon group) but also a hydrocarbon group having a substituent (substituted hydrocarbon group). The same applies to each compound.

The term "radiation" in the present invention refers to, for example, extreme ultraviolet rays (EUV), X-rays, electron beams, or the like. In the present invention, light refers to actinic rays or radiation. The "exposure" in the present invention includes, unless otherwise specified, not only exposure by extreme ultraviolet rays, X-rays, EUV, or the like, but also drawing by a particle beam such as an electron beam or an ion beam.

[ medicinal solution ]

A chemical solution (hereinafter, also referred to as "the chemical solution") according to an embodiment of the present invention contains an organic solvent and metal-containing particles containing metal atoms, wherein the number of the metal nanoparticles having a particle diameter of 0.5 to 17nm among the metal-containing particles contained in the chemical solution is 1.0 × 10¹～1.0×10⁹Per cm³。

Although the mechanism by which the above problems are solved by the present chemical solution is not clear, the present inventors speculate as follows. The following mechanism is assumed to be included in the scope of the present invention even when the effects of the present invention are obtained by a different mechanism.

One of the characteristics of the chemical liquid is that the number of metal nanoparticles with the particle diameter of 0.5-17 nm in the chemical liquid is controlled to be 1.0 × 10¹～1.0×10⁹Per cm³。

In the step of applying EUV exposure, it is required to reduce the pitch of the pattern obtained by adding the pattern pitch and the pattern width of the resist to 1 pattern width and the pattern pitch of the periodic arrangement, and to reduce the pitch of the wiring obtained by adding the pitch of the wiring to 1 wiring width and the wiring pitch of the periodic arrangement.

Specifically, the pattern width and/or the pattern interval are usually about 10 to 15nm (in this case, the pattern pitch is usually 20 to 30 nm). In this case, the present inventors have found that it is required to control finer particles in units of the number thereof, which does not cause a problem in the conventional process.

Among the above particles, the metal-containing particles having a particle size of less than 0.5nm are more likely to aggregate, and as a result, generally coarse particles are formed, and therefore, the particles are generally removed in a step (for example, in a form such as rinsing), and it is presumed that the effect on the defect suppressing performance of the chemical solution is not so large.

On the other hand, since the metal-containing particles having a particle diameter of more than 17nm among the particles are sufficiently larger than the required resist pitch, they are generally removed in the step as described above, and it is estimated that the influence on the defect suppression performance of the chemical solution is not so large.

It is estimated that metal nanoparticles having a particle diameter of 0.5 to 17nm tend to be less easily removed from a substrate, and the number of particles contained in the metal nanoparticles per unit volume of a chemical solution is 1.0 × 10¹Per cm³As described above, the metal nanoparticles are likely to aggregate with each other and are more easily removed in the step, and as a result, the chemical solution is expected to have excellent defect suppression performance.

On the other hand, if the number of particles contained in the metal nanoparticles per unit volume of the chemical solution is 1.0 × 10⁹Per cm³The metal nanoparticles themselves can be suppressed from causing defects, and as a result, the chemical solution is presumed to have excellent defect suppression performance.

The content of the metal nanoparticles in the chemical solution can be measured by the method described in examples, and the number (number) of particles of the metal nanoparticles per unit volume of the chemical solution is determined by performing four-sheet-fed analysis with five-in-one so that the significant figure becomes 2 digits.

[ organic solvent ]

The liquid medicine contains an organic solvent. The content of the organic solvent in the chemical solution is not particularly limited, but is usually preferably 98.0 mass% or more, more preferably 99.0 mass% or more, further preferably 99.9 mass% or more, and particularly preferably 99.99 mass% or more, based on the total mass of the chemical solution. The upper limit is not particularly limited, but is usually less than 100 mass%.

The organic solvent may be used alone in 1 kind, or may be used in combination in 2 or more kinds. In the case where 2 or more organic solvents are used simultaneously, the total content is preferably within the above range.

In the present specification, the organic solvent refers to a liquid organic compound containing 1 component at a content of more than 10000 ppm by mass relative to the total mass of the chemical solution. That is, in the present specification, the liquid organic compound contained in an amount exceeding 10000 ppm by mass relative to the total mass of the chemical solution corresponds to the organic solvent.

In the present specification, the term "liquid" means a liquid at 25 ℃ under atmospheric pressure.

The type of the organic solvent is not particularly limited, and a known organic solvent can be used. Examples of the organic solvent include alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate, alkyl alkoxypropionate, cyclic lactone (preferably 4 to 10 carbon atoms), monoketone compound which may have a ring (preferably 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.

Further, as the organic solvent, for example, those described in Japanese patent laid-open Nos. 2016-057614, 2014-219664, 2016-138219, and 2015-135379 can be used.

As the organic solvent, at least one selected from the group consisting of propylene glycol monomethyl ether, Propylene Glycol Monoethyl Ether (PGME), propylene glycol monopropyl ether, Propylene Glycol Monomethyl Ether Acetate (PGMEA), Ethyl Lactate (EL), methyl methoxypropionate, cyclopentanone, Cyclohexanone (CHN), γ -butyrolactone, diisoamyl ether, butyl acetate (nBA), isoamyl acetate, isopropanol, 4-methyl-2-pentanol, dimethyl sulfoxide, n-methyl-2-pyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, Propylene Carbonate (PC), sulfolane, cycloheptanone, 1-hexanol, decane, and 2-heptanone is preferable. Among them, CHN, PGMEA, PGME, nBA, PC, and a mixture thereof are preferable from the viewpoint of obtaining a chemical solution having more excellent effects of the present invention.

In addition, the organic solvent can be used alone in 1, also can be used simultaneously more than 2.

In addition, the type and content of the organic solvent in the chemical solution can be measured using a gas chromatography-mass spectrometer.

[ Metal-containing particles ]

The chemical solution contains metal-containing particles containing metal atoms.

Although a preferred embodiment of the method for producing the chemical liquid will be described later, the chemical liquid can be produced by purifying a purified product containing the organic solvent and the impurities described above. The metal-containing particles may be intentionally added in the process of producing the chemical solution, may be originally contained in the purified product, or may be transferred from the apparatus for producing the chemical solution or the like in the process of producing the chemical solution (so-called contamination).

The metal atom is not particularly limited, but examples thereof include an Fe atom, an Al atom, a Cr atom, a Ni atom, a Pb atom, a Zn atom, a Ti atom, and the like. Among them, if the content of the metal-containing particles containing at least one selected from the group consisting of Fe atoms, Al atoms, Pb atoms, Zn atoms, and Ti atoms in the chemical solution is strictly controlled, more excellent defect suppression performance is easily obtained, and if the content of the metal-containing particles containing at least one selected from the group consisting of Pb atoms and Ti atoms in the chemical solution is strictly controlled, further excellent defect suppression performance is easily obtained.

That is, the metal atom is preferably at least one selected from the group consisting of an Fe atom, an Al atom, a Cr atom, a Ni atom, a Pb atom, a Zn atom, a Ti atom, and the like, more preferably at least one selected from the group consisting of an Fe atom, an Al atom, a Pb atom, a Zn atom, and a Ti atom, further preferably at least one selected from the group consisting of a Pb atom and a Ti atom, and particularly preferably the metal-containing particle further contains any one of a Pb atom and a Ti atom.

The metal-containing particles may contain 1 kind of the metal atom alone, or 2 or more kinds of the metal atom simultaneously.

The particle size of the metal-containing particles is not particularly limited, but for example, in a chemical solution for manufacturing a semiconductor device, the content of particles having a particle size of about 0.1 to 100nm in the chemical solution is generally controlled.

Among them, according to the studies of the present inventors, it has been found that a chemical solution having excellent defect suppression performance can be easily obtained by controlling the content of metal-containing particles (hereinafter, also referred to as "metal nanoparticles") having a particle diameter of 0.5 to 17nm in the chemical solution, particularly in the resist step applied to EUV exposure. As described above, in the resist step of EUV exposure, a fine resist pitch, resist width, and resist pitch are generally required. In this case, it is required to control finer particles in units of the number thereof, which has not been a problem in the conventional process.

The particle size distribution based on the number of the metal-containing particles is not particularly limited, but it is preferable that the maximum value is in at least one range selected from the group consisting of a range having a particle size of less than 5nm and a range having a particle size of more than 17nm from the viewpoint of obtaining a chemical solution having more excellent effects of the present invention.

In other words, it is preferable that the particle size of the particles has no maximum value in the range of 5 to 17 nm. The liquid medicine has a maximum value in a particle size range of 5 to 17nm, and therefore has more excellent defect suppression performance, particularly more excellent bridging defect suppression performance. The bridging defect suppression performance is a defect evaluated by the method described in examples.

Further, from the viewpoint of obtaining a chemical solution having a further excellent effect of the present invention, it is more preferable that the number-based particle size distribution has a maximum value in a range of particle sizes of 0.5nm or more and less than 5 nm. As described above, the chemical solution has further excellent bridging defect inhibiting ability.

< Metal nanoparticles >

The metal nanoparticles are metal-containing particles having a particle diameter of 0.5 to 17 nm.

The number of the metal nanoparticles contained per unit volume of the chemical solution was 1.0 × 10¹～1.0×10⁹Per cm³From the viewpoint that the present chemical solution has more excellent effects of the present invention, the number of particles contained is preferably 1.0 × 10²Per cm³The above, more preferably 1.0 × 10³Per cm³Above, preferably 1.0 × 10⁶Per cm³Hereinafter, more preferably 1.0 × 10⁵Per cm³Hereinafter, 1.× 10 is more preferable⁴Per cm³The following.

The number of the metal nanoparticles per unit volume of the chemical solution is 1.0 × 10²～1.0×10⁶Per cm³The chemical solution has more excellent defect-suppressing performance.

The metal atoms contained in the metal nanoparticles are not particularly limited, but are the same as the metal atoms described above as the metal atoms contained in the metal-containing particles. Among these, in view of obtaining a chemical solution having more excellent effects of the present invention, the metal atom is preferably at least one selected from the group consisting of a Pb atom and a Ti atom, and more preferably the metal nanoparticle contains both a Pb atom and a Ti atom. In other words, the metal nanoparticles preferably contain at least one selected from the group consisting of metal nanoparticles containing Pb atoms (hereinafter, also referred to as "Pb nanoparticles") and metal nanoparticles containing Ti atoms (hereinafter, also referred to as "Ti nanoparticles"), and more preferably contain both Pb and Ti nanoparticles.

The metal nanoparticles contain both Pb atoms and Ti atoms, and typically, there is a mode in which the chemical solution contains both Pb atom-containing metal nanoparticles and Ti atom-containing metal nanoparticles.

The ratio of the number of particles contained in the Pb nanoparticles and Ti nanoparticles in the chemical solution (Pb/Ti) is not particularly limited, but is preferably 1.0 × 10 in general^-43.0, more preferably 1.0 × 10^-32.0, more preferably 1.0 × 10^-2About 1.5. if Pb/Ti is 1.0 × 10^-3When the concentration is about 2.0, the chemical solution has more excellent effects of the present invention, and particularly has more excellent bridging defect suppressing performance.

The inventors of the present invention found that: for example, the Pb nanoparticles and Ti nanoparticles are likely to be associated with each other when a chemical solution is applied onto a wafer, and are likely to cause defects (particularly, cause bridging defects) when a resist film is developed.

If the Pb/Ti ratio is 1.0 × 10^-32.0, it is surprising that the generation of defects is more easily suppressed. In the present specification, Pb/Ti, a/(B + C) described later, and U/V described later are obtained by performing four-sheet five-fold calculation so that the significant number becomes 2 digits.

The metal nanoparticles may contain metal atoms in a manner not particularly limited. Examples thereof include a simple metal atom, a compound containing a metal atom (hereinafter, also referred to as "metal compound"), and a composite thereof. Also, the metal nanoparticles may contain a variety of metal atoms. When the metal nanoparticles contain a plurality of metals, the metal atoms having the largest content (atm%) among the plurality of metals are used as the main component. Therefore, the Pb nanoparticles refer to a case where a plurality of metals are contained, and Pb atoms are a main component in the plurality of metals.

The compound is not particularly limited, but includes: a core-shell particle having a simple metal atom and a metal compound covering at least a part of the simple metal atom; solid solution particles comprising metal atoms and other atoms; eutectic particles comprising metal atoms and other atoms; aggregate particles of a simple metal atom and a metal compound; aggregate particles of different kinds of metal compounds; and a metal compound having a composition which changes continuously or intermittently from the particle surface to the center; and the like.

The atoms other than the metal atom contained in the metal compound are not particularly limited, but examples thereof include a carbon atom, an oxygen atom, a nitrogen atom, a hydrogen atom, a sulfur atom, a phosphorus atom and the like, and among them, an oxygen atom is preferable. The mode of the metal compound containing an oxygen atom is not particularly limited, but an oxide of a metal atom is more preferable.

From the viewpoint of obtaining a chemical solution having more excellent effects of the present invention, the metal nanoparticles preferably include at least one selected from the group consisting of particles containing a simple metal atom (particles a), particles containing an oxide of a metal atom (particles B), and particles containing a simple metal atom and an oxide of a metal atom (particles C).

Further, the relationship among the number of particles contained in the particle a, the number of particles contained in the particle B, and the number of particles contained in the particle C, in the number of particles contained in the metal nanoparticle, as per unit volume of the chemical solution, is not particularly limited, but from the viewpoint of obtaining a chemical solution having a more excellent effect of the present invention, the ratio of the number of particles contained in the particle a to the number of particles contained in the total of the number of particles contained in the particle B and the number of particles contained in the particle C (hereinafter, also referred to as "a/(B + C)") is preferably 1.5 or less, more preferably less than 1.0, and still more preferably 2.0 × 10^-1Hereinafter, 1.0 × 10 is particularly preferable^-1Hereinafter, 1.0 × 10 is preferable^-3The above, more preferably 1.0 × 10^-2The above.

When a/(B + C) is less than 1.0, the chemical solution has more excellent bridging defect suppressing performance, more excellent pattern width uniformity performance, and more excellent spot defect suppressing performance.

When A/(B + C) is 0.1(1.0 × 10)^-1) The following are more excellent residue defect inhibiting properties of the chemical solution.

[ other Components ]

The chemical solution may contain other components than those described above. Examples of the other components include organic compounds other than organic solvents (particularly, organic compounds having a boiling point of 300 ℃ or higher), water, and resins.

< organic Compound other than organic solvent >

The chemical solution may contain an organic compound other than the organic solvent (hereinafter, also referred to as "specific organic compound"). In the present specification, the specific organic compound is a compound different from the organic solvent contained in the chemical solution, and means an organic compound contained in a content of 10000 ppm by mass or less with respect to the total mass of the chemical solution. That is, in the present specification, the organic compound contained in a content of 10000 ppm by mass or less relative to the total mass of the chemical solution corresponds to a specific organic compound and does not correspond to an organic solvent.

In addition, when the chemical solution contains a plurality of organic compounds and each organic compound is contained in the content of 10000 mass ppm or less, the chemical solution corresponds to a specific organic compound.

The specific organic compound may be added to the chemical solution or may be mixed at will in the process of producing the chemical solution. Examples of the case where the solvent is mixed at will in the chemical liquid production process include, for example, a case where a specific organic compound is contained in a raw material (for example, an organic solvent) for producing the chemical liquid, a case where a specific organic compound is mixed (for example, contaminated) in the chemical liquid production process, and the like, but are not limited to the above.

The content of the specific organic compound in the chemical solution can be measured by GCMS (gas chromatography mass spectrometry).

The number of carbon atoms of the specific organic compound is not particularly limited, but is preferably 8 or more, more preferably 12 or more, from the viewpoint that the chemical solution has more excellent effects of the present invention. The upper limit of the number of carbon atoms is not particularly limited, but is preferably 30 or less.

The specific organic compound may be, for example, a by-product produced by the synthesis of an organic solvent and/or an unreacted raw material (hereinafter, also referred to as a "by-product or the like").

Examples of the by-products include compounds represented by the following formulae I to V.

[ chemical formula 1]

In the formula I, R₁And R₂Each independently represents an alkyl group or a cycloalkyl group, or they are bonded to each other to form a ring.

As a group consisting of R₁And R₂The alkyl group or cycloalkyl group is preferably an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 6 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 6 to 8 carbon atoms.

R₁And R₂Rings formed by bonding to each otherIs a lactone ring, preferably a lactone ring having 4 to 9 membered rings, more preferably a lactone ring having 4 to 6 membered rings.

In addition, R is preferred₁And R₂Satisfies the relationship that the number of carbon atoms of the compound represented by the formula I is 8 or more.

In the formula II, R₃And R₄Each independently represents a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group or a cycloalkenyl group, or they are bonded to each other to form a ring. Wherein R is₃And R₄Neither of these will be hydrogen atoms.

As a group consisting of R₃And R₄The alkyl group represented by (A) is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms.

As a group consisting of R₃And R₄The alkenyl group represented by (A) is preferably an alkenyl group having 2 to 12 carbon atoms, and more preferably an alkenyl group having 2 to 8 carbon atoms.

As a group consisting of R₃And R₄The cycloalkyl group represented by (A) is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 8 carbon atoms.

As a group consisting of R₃And R₄The cycloalkenyl group represented by (a) is, for example, preferably a cycloalkenyl group having 3 to 12 carbon atoms, and more preferably a cycloalkenyl group having 6 to 8 carbon atoms.

R₃And R₄The ring formed by bonding is a cyclic ketone structure, and may be a saturated cyclic ketone or an unsaturated cyclic ketone. The cyclic ketone is preferably 6 to 10-membered ring, more preferably 6 to 8-membered ring.

In addition, R₃And R₄It is preferable that the number of carbon atoms of the compound represented by formula II is 8 or more.

In the formula III, R₅Represents an alkyl group or a cycloalkyl group.

Preferably from R₅The alkyl group is an alkyl group having 6 or more carbon atoms, 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 ether bond in the chain or may have a substituent such as a hydroxyl group.

Preferably from R₅A cycloalkyl group represented byIs a cycloalkyl group having 6 or more carbon atoms, more preferably a cycloalkyl group having 6 to 12 carbon atoms, and still more preferably a cycloalkyl group having 6 to 10 carbon atoms.

In the formula IV, R₆And R₇Each independently represents an alkyl group or a cycloalkyl group, or they are bonded to each other to form a ring.

As a group consisting of R₆And R₇The alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms.

As a group consisting of R₆And R₇The cycloalkyl group represented by (A) is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 8 carbon atoms.

R₆And R₇The rings formed by bonding to each other are cyclic ether structures. The cyclic ether structure is preferably a 4-to 8-membered ring, more preferably a 5-to 7-membered ring.

In addition, R is preferred₆And R₇Satisfies the relationship that the number of carbon atoms of the compound represented by the formula IV is 8 or more.

In the formula V, R₈And R₉Each independently represents an alkyl group or a cycloalkyl group, or they are bonded to each other to form a ring. L represents a single bond or an alkylene group.

As a group consisting of R₈And R₉The alkyl group represented by (A) is preferably an alkyl group having 6 to 12 carbon atoms, and more preferably an alkyl group having 6 to 10 carbon atoms.

As a group consisting of R₈And R₉The cycloalkyl group represented by (A) is preferably a cycloalkyl group having 6 to 12 carbon atoms, more preferably a cycloalkyl group having 6 to 10 carbon atoms.

R₈And R₉The rings formed by bonding to each other are cyclic diketone structures. The cyclic diketone structure is preferably a 6-to 12-membered ring, more preferably a 6-to 10-membered ring.

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.

In addition, R₈、R₉And L satisfies the relationship that the number of carbon atoms of the compound represented by the formula V is 8 or more.

Although not particularly limited, when the organic solvent is an amide compound, an imide compound, or a sulfoxide compound, one embodiment of the amide compound, the imide compound, or the sulfoxide compound having 6 or more carbon atoms is exemplified. Further, as the specific organic compound, for example, the following compounds can be mentioned.

[ chemical formula 2]

[ chemical formula 3]

Further, specific organic compounds include: antioxidants such as dibutylhydroxytoluene (BHT), distearyl thiodipropionate (DSTP), 4 '-butylidenebis- (6-tert-butyl-3-methylphenol), 2' -methylenebis- (4-ethyl-6-tert-butylphenol), and the antioxidants described in Japanese patent laid-open publication No. 2015 200775; unreacted starting materials; structural isomers and by-products generated in the production of organic solvents; and a dissolved material from a member constituting a manufacturing apparatus of an organic solvent or the like (for example, a plasticizer dissolved from a rubber member such as an O-ring); and the like.

Further, specific examples of the organic compound include dioctyl phthalate (DOP), bis (2-ethylhexyl) phthalate (DEHP), bis (2-propylheptyl) phthalate (DPHP), dibutyl phthalate (DBP), benzylbutyl phthalate (BBzP), diisodecyl phthalate (DIDP), diisooctyl phthalate (DIOP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), dihexyl phthalate, diisononyl phthalate (DINP), tris (2-ethylhexyl) trimellitate (TEHTM), tris (n-octyl-n-decyl) trimellitate (ATM), bis (2-ethylhexyl) adipate (DEHA), monomethyl adipate (MMAD), dioctyl adipate (DOA), dibutyl sebacate (DBS), dibutyl maleate (DBM), Diisobutyl maleate (DIBM), azelaic acid ester, benzoic acid ester, terephthalic acid (e.g., dioctyl terephthalate (DEHT)), diisononyl 1, 2-cyclohexanedicarboxylate (DINCH), epoxidized vegetable oil, sulfonamide (e.g., N- (2-hydroxypropyl) benzenesulfonamide (HP BSA), N- (N-butyl) benzenesulfonamide (BBSA-NBBS)), organic phosphate (e.g., tricresyl phosphate (TCP), tributyl phosphate (TBP)), acetylated monoglyceride, triethyl citrate (TEC), acetyl triethyl citrate (ATEC), tributyl citrate (TBC), acetyl tributyl citrate (ATBC), trioctyl citrate (TOC), acetyl trioctyl citrate (ATOC), trihexyl citrate (THC), acetyl trihexyl citrate (ATHC), epoxidized soybean oil, ethylene propylene rubber, Polybutene, an addition polymer of 5-ethylene-2-norbornene, and the following examples of the polymeric plasticizers.

It is presumed that these specific organic compounds are mixed into the purified product or the chemical solution from a filter, piping, a tank, an O-ring (O-ring), a container, and the like which are brought into contact in the purification step. In particular, compounds other than alkyl olefins are associated with the generation of bridging defects.

[ chemical formula 4]

(organic Compound having a boiling point of 300 ℃ or higher)

The chemical solution may contain an organic compound (high boiling point organic compound) having a temperature of 300 ℃ or higher among the specific organic compounds. When the chemical contains an organic compound having a boiling point of 300 ℃ or higher, the boiling point is high and the chemical is not easily volatilized in the photolithography step. Therefore, in order to obtain a chemical solution having excellent defect-inhibiting performance, it is necessary to strictly control the content, the existence pattern, and the like of the high-boiling organic compound in the chemical solution.

Examples of such high-boiling organic compounds include dioctyl phthalate (having a boiling point of 385 ℃), diisononyl phthalate (having a boiling point of 403 ℃), dioctyl adipate (having a boiling point of 335 ℃), dibutyl phthalate (having a boiling point of 340 ℃) and ethylene propylene rubber (having a boiling point of 300 to 450 ℃).

The inventors of the present invention found that: when the chemical liquid contains a high boiling point organic compound, there are various modes. Examples of the mode of existence of the high boiling point organic compound in the chemical solution include: particles obtained by aggregating particles containing a metal atom or a metal compound with particles of a high boiling point organic compound; particles having particles containing a metal atom or a metal compound and a high-boiling organic compound disposed so as to cover at least a part of the particles; and particles formed by coordination bonding of a metal atom and a high boiling point organic compound; and the like.

Among them, as a mode having a large influence on the defect-suppressing performance of the chemical solution, there can be mentioned metal nanoparticles (particles U) containing an organic compound (preferably a high boiling point organic compound). The inventors of the present invention found that: by controlling the number of particles U contained per unit volume of the chemical solution, the defect suppressing performance of the chemical solution is dramatically improved.

Although the reason is not clear, the surface free energy of the particle U is relatively easy to be smaller than that of the metal nanoparticle (particle V) containing no organic compound (preferably, high boiling point organic compound). Such particles U are not likely to remain on the substrate treated with the chemical solution, and even if they remain, they are likely to be removed when they are again brought into contact with the chemical solution. For example, when a chemical solution is used as the developing solution or the rinse solution, the particles U are less likely to remain on the substrate during development and are easily removed by rinsing or the like. That is, as a result, both the organic compound (preferably, high boiling point organic compound) and the particles containing the metal atom can be removed more easily.

In addition, since the resist film is generally hydrophobic in most cases, it is assumed that the particles U having a lower surface energy are less likely to remain on the substrate.

The ratio of the number of particles containing particles U to the number of particles containing particles V per unit volume of the chemical solution is preferably 10(1.0 × 10) from the viewpoint of obtaining a chemical solution having more excellent effects of the present invention¹) Above, preferably 1.0 × 10²The content is more preferably 50 or less, still more preferably 35 or less, and particularly preferably 25 or less.

< water >)

The chemical solution may contain water. The water is not particularly limited, and for example, distilled water, ion-exchanged water, pure water, or the like can be used. In addition, the organic impurities do not contain water.

The water may be added to the chemical solution, or may be optionally mixed with the chemical solution in the process of producing the chemical solution. Examples of the case where the solvent is mixed at will in the chemical liquid production process include, for example, a case where water is contained in a raw material (for example, an organic solvent) for producing the chemical liquid, and a case where water is mixed (for example, contaminated) in the chemical liquid production process, but the present invention is not limited to the above.

The content of water in the chemical solution is not particularly limited, but is preferably 0.05 to 2.0 mass% based on the total mass of the chemical solution. The content of water in the chemical solution means a water content measured using a device using a karl fischer (karl fischer) water measurement method as a measurement principle.

< resin >

The chemical solution may further contain a resin. As the resin, a resin P having a group which is decomposed by the action of an acid to generate a polar group is preferable. As the resin, a resin having a repeating unit represented by formula (AI) described later, which is a resin whose solubility in a developer mainly containing an organic solvent is reduced by the action of an acid, is more preferable. The resin having a repeating unit represented by formula (AI) described later has a group which is decomposed by the action of an acid to generate an alkali-soluble group (hereinafter, also referred to as "acid-decomposable group").

Examples of the polar group include alkali-soluble groups. Examples of the alkali-soluble group include a carboxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), a phenolic hydroxyl group, and a sulfonic acid group.

In the acid-decomposable group, the polar group is protected by a group (acid leaving group) which is removed by an acid. As the acid leaving group, for example, there may be mentioned-C (R)₃₆)(R₃₇)(R₃₈)、-C(R₃₆)(R₃₇)(OR₃₉) and-C (R)₀₁)(R₀₂)(OR₃₉) And the like.

In the formula, R₃₆～R₃₉Each independently represents an alkyl group, a cycloalkyl group, or an aryl groupAralkyl or alkenyl. R₃₆And R₃₇May be bonded to each other to form a ring.

R₀₁And R₀₂Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.

The resin P whose solubility in a developer mainly composed of an organic solvent is reduced by the action of an acid will be described in detail below.

(formula (AI): repeating unit having acid-decomposable group)

Preferably, the resin P contains a repeating unit represented by formula (AI).

[ chemical formula 5]

In the formula (AI), the reaction mixture is,

Xa₁represents a hydrogen atom or an alkyl group which may have a substituent.

T represents a single bond or a 2-valent linking group.

Ra₁～Ra₃Each independently represents an alkyl group (linear or branched) or a cycloalkyl group (monocyclic or polycyclic).

Ra₁～Ra₃2 of which may be bonded to form a cycloalkyl group (monocyclic or polycyclic).

As a result of Xa₁Examples of the optionally substituted alkyl group include a methyl group and a group represented by-CH₂-R₁₁The group shown. R₁₁Represents a halogen atom (e.g., fluorine atom), a hydroxyl group, or a 1-valent organic group.

Xa₁Preferably a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

Examples of the linking group having a valence of 2 in T include an alkylene group, a-COO-Rt-group, and a-O-Rt-group. Wherein Rt represents an alkylene group or a cycloalkylene group.

T is preferably a single bond or a-COO-Rt-group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, and more preferably-CH₂-radical, - (CH)₂)₂-radical or- (CH)₂)₃-a radical.

As Ra₁～Ra₃The alkyl group of (2) is preferably a C1-4 alkyl group.

As Ra₁～Ra₃The cycloalkyl group of (2) is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecyl group, a tetracyclododecyl group, or an adamantyl group.

As Ra₁～Ra₃The cycloalkyl group in which 2 of them are bonded is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecyl group, a tetracyclododecyl group or an adamantyl group. More preferably a monocyclic cycloalkyl group having 5 to 6 carbon atoms.

Ra₁～Ra₃In the above cycloalkyl group in which 2 of them are bonded, for example, 1 of methylene groups constituting the ring may be substituted with a group having a heteroatom such as an oxygen atom or a heteroatom such as a carbonyl group.

Repeating units preferably represented by formula (AI) such as Ra₁Is methyl or ethyl, and Ra₂And Ra₃And bonded to form the cycloalkyl group.

Each of the above groups may have a substituent, and examples of the substituent include an alkyl group (having 1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (having 1 to 4 carbon atoms), a carboxyl group, and an alkoxycarbonyl group (having 2 to 6 carbon atoms), and the number of carbon atoms is preferably 8 or less.

The content of the repeating unit represented by the formula (AI) is preferably 20 to 90 mol%, more preferably 25 to 85 mol%, and further preferably 30 to 80 mol% with respect to all repeating units in the resin P.

(repeating Unit having lactone Structure)

Further, the resin P preferably contains a repeating unit Q having a lactone structure.

The repeating unit Q having a lactone structure preferably has a lactone structure in a side chain, and a repeating unit derived from a (meth) acrylic acid derivative monomer is more preferred.

The repeating unit Q having a lactone structure may be used alone in 1 kind or in combination of 2 or more kinds, but it is preferable to use 1 kind alone.

The content of the repeating unit Q having a lactone structure is preferably 3 to 80 mol%, more preferably 3 to 60 mol% with respect to all repeating units in the resin P.

The lactone structure is preferably a 5-to 7-membered ring lactone structure, and more preferably a structure in which other ring structures are condensed in a form of a bicyclic structure or a spiro structure formed in the 5-to 7-membered ring lactone structure.

It is preferable that the lactone compound has a lactone structure represented by any one of the following formulae (LC1-1) to (LC1-17) as a repeating unit of the lactone structure. The lactone structure is preferably a lactone structure represented by formula (LC1-1), formula (LC1-4), formula (LC1-5) or formula (LC1-8), and more preferably a lactone structure represented by formula (LC 1-4).

[ chemical formula 6]

The lactone moiety may have a substituent (Rb)₂). As preferred substituent (Rb)₂) Examples thereof include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a carboxyl group, a halogen atom, a hydroxyl group, a cyano group, an acid-decomposable group and the like. n is₂Represents an integer of 0 to 4. n is₂When it is 2 or more, a plurality of substituents (Rb)₂) May be the same or different, and a plurality of substituents (Rb) are present₂) May be bonded to each other to form a ring.

(repeating Unit having phenolic hydroxyl group)

The resin P may contain a repeating unit having a phenolic hydroxyl group.

Examples of the repeating unit having a phenolic hydroxyl group include a repeating unit represented by the following general formula (I).

[ chemical formula 7]

In the formula (I), the compound is shown in the specification,

R₄₁、R₄₂and R₄₃Each independently represents a hydrogen atom, an alkyl group, a halogen atom, a cyano group or an alkoxycarbonyl group. Wherein R is₄₂May be reacted with Ar₄Bonded to form a ring, in which case R₄₂Represents a single bond or an alkylene group.

X₄Represents a single bond, -COO-or-CONR₆₄-，R₆₄Represents a hydrogen atom or an alkyl group.

L₄Represents a single bond or an alkylene group.

Ar₄An aromatic ring group having a (n +1) valence as defined in the formula₄₂When the bond forms a ring, it represents an (n +2) -valent aromatic ring group.

n represents an integer of 1 to 5.

As R in the general formula (I)₄₁、R₄₂And R₄₃The alkyl group (b) is preferably an alkyl group having not more than 20 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a hexyl group, a 2-ethylhexyl group, an octyl group, and a dodecyl group, which may have a substituent, more preferably an alkyl group having not more than 8 carbon atoms, and still more preferably an alkyl group having not more than 3 carbon atoms.

As R in the general formula (I)₄₁、R₄₂And R₄₃The cycloalkyl group of (b) may be monocyclic or polycyclic. The cycloalkyl group is preferably a monocyclic cycloalkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group, which may have a substituent.

As R in the general formula (I)₄₁、R₄₂And R₄₃Examples of the halogen atom of (2) include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

As R in the general formula (I)₄₁、R₄₂And R₄₃The alkyl group contained in the alkoxycarbonyl group of (1) is preferably the same as the above-mentioned R₄₁、R₄₂And R₄₃The alkyl groups in (1) are the same.

Examples of the substituent in each of the above groups include an alkyl group, a cycloalkyl group, an aryl group, an amino group, an amide group, an urea group, a urethane group, a hydroxyl group, a carboxyl group, a halogen atom, an alkoxy group, a thioether group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a cyano group, and a nitro group, and the number of carbon atoms in the substituent is preferably 8 or less.

Ar₄Represents an (n +1) -valent aromatic ring group. When n is 1, the 2-valent aromatic ring group may have a substituent, and examples thereof include arylene groups having 6 to 18 carbon atoms such as phenylene, tolylene, naphthylene and anthracenylene, and heterocyclic ring-containing aromatic ring groups such as thiophene, furan, pyrrole, benzothiophene, benzofuran, benzopyrrole, triazine, imidazole, benzimidazole, triazole, thiadiazole and thiazole.

Specific examples of the (n +1) -valent aromatic ring group in which n is an integer of 2 or more include groups obtained by removing (n-1) arbitrary hydrogen atoms from the specific examples of the 2-valent aromatic ring group.

The (n +1) -valent aromatic ring group may further have a substituent.

Examples of the substituent which the alkyl group, cycloalkyl group, alkoxycarbonyl group, alkylene group and (n +1) -valent aromatic ring group may have include R in the general formula (I)₄₁、R₄₂And R₄₃The alkyl groups mentioned in (1); alkoxy groups such as methoxy, ethoxy, hydroxyethoxy, propoxy, hydroxypropoxy, and butoxy; aryl groups such as phenyl.

As a result of X₄Represented by-CONR₆₄-(R₆₄Represents a hydrogen atom or an alkyl group. ) R in (1)₆₄Examples of the alkyl group of (b) include alkyl groups having not more than 20 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a hexyl group, a 2-ethylhexyl group, an octyl group and a dodecyl group, which may have a substituent, and an alkyl group having not more than 8 carbon atoms is more preferable.

As X₄Preferably a single bond, -COO-or-CONH-, more preferably a single bond or-COO-.

As L₄The alkylene group in (1) is preferably an alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and an octylene group, which may have a substituent.

As Ar₄The aromatic ring group having 6 to 18 carbon atoms, which may have a substituent, is preferable, and a benzene ring group, a naphthalene ring group or a biphenylene ring group is more preferable.

The repeating unit represented by the general formula (I) preferably has a hydroxystyrene structure. Namely, Ar₄Preferably a benzene ring group.

The content of the repeating unit having a phenolic hydroxyl group is preferably 0 to 50 mol%, more preferably 0 to 45 mol%, and further preferably 0 to 40 mol% with respect to all repeating units in the resin P.

(repeating units having organic group having polar group)

The resin P may further contain a repeating unit containing an organic group having a polar group, particularly a repeating unit having an alicyclic hydrocarbon structure substituted with a polar group. Therefore, the substrate adhesion and the developer affinity are improved.

The alicyclic hydrocarbon structure of the alicyclic hydrocarbon structure obtained by substitution with a polar group is preferably an adamantyl group, a diamantyl group, or a norbornyl group. As the polar group, a hydroxyl group or a cyano group is preferable.

In the case where the resin P contains a repeating unit containing a 0149 organic group having a polar group, the content thereof is preferably 1 to 50 mol%, more preferably 1 to 30 mol%, further preferably 5 to 25 mol%, and particularly preferably 5 to 20 mol% with respect to all repeating units in the resin P.

(repeating unit represented by the general formula (VI))

The resin P may contain a repeating unit represented by the following general formula (VI).

[ chemical formula 8]

In the general formula (VI), the compound represented by the formula (VI),

R₆₁、R₆₂and R₆₃Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. Wherein R is₆₂May be reacted with Ar₆Bonded to form a ring, in which case R₆₂Represents a single bond or an alkylene group.

X₆Represents a single bond, -COO-or-CONR₆₄-。R₆₄Represents a hydrogen atom or an alkyl group。

L₆Represents a single bond or an alkylene group.

Ar₆An aromatic ring group having a (n +1) valence as defined in the formula₆₂When the bond forms a ring, it represents an (n +2) -valent aromatic ring group.

With respect to Y₂And when n.gtoreq.2, each independently represents a hydrogen atom or a group which is removed by the action of an acid. Wherein, Y₂At least 1 of which represents a group that is removed by the action of an acid.

n represents an integer of 1 to 4.

As a group Y leaving by the action of an acid₂The structure represented by the following general formula (VI-A) is preferable.

[ chemical formula 9]

L₁And L₂Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group obtained by combining an alkylene group and an aryl group.

M represents a single bond or a 2-valent linking group.

Q represents an alkyl group, a cycloalkyl group which may contain a heteroatom, an aryl group which may contain a heteroatom, an amino group, an ammonium group, a mercapto group, a cyano group or an aldehyde group.

Q、M、L₁At least 2 of which may be bonded to form a ring (preferably a 5-or 6-membered ring).

The repeating unit represented by the above general formula (VI) is preferably a repeating unit represented by the following general formula (3).

[ chemical formula 10]

In the general formula (3), in the formula,

Ar₃represents an aromatic ring group.

R₃Represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an acyl group or a heterocyclic group.

M₃Represents a single bond or a 2-valent linking group.

Q₃Represents an alkyl group, a cycloalkyl group, an aryl group or a heterocyclic group.

Q₃、M₃And R₃At least 2 of which may be bonded to form a ring.

Ar₃The aromatic ring group represented by (VI) and Ar in the general formula (VI) in the case where n in the general formula (VI) is 1₆Likewise, phenylene or naphthylene is preferred, and phenylene is more preferred.

(repeating unit having silicon atom in side chain)

The resin P may further contain a repeating unit having a silicon atom on a side chain. Examples of the repeating unit having a silicon atom in a side chain include a (meth) acrylate-based repeating unit having a silicon atom, a vinyl-based repeating unit having a silicon atom, and the like. Examples of the repeating unit having a silicon atom in a side chain include a repeating unit having a group having a silicon atom in a side chain, and examples of the group having a silicon atom include a trimethylsilyl group, a triethylsilyl group, a triphenylsilyl group, a tricyclohexylsilyl group, a tris (trimethylsiloxy) silyl group, a tris (trimethylsilyl) silyl group, a methyldimethylsilyl group, a methyldimethylsilyloxysilyl group, a dimethyltrimethylsilyl group, a dimethyltrimethylsiloxysilyl group, a cyclic or linear polysiloxane as described below, a cage-type or ladder-type or random-type silsesquioxane structure, and the like. In the formula, R and R¹Each independently represents a substituent having a valence of 1. The symbol represents a linear bond.

[ chemical formula 11]

As the repeating unit having the above group, for example, a repeating unit derived from an acrylate compound or a methacrylate compound having the above group or a repeating unit derived from a compound having the above group and a vinyl group is preferable.

When the resin P has a repeating unit having a silicon atom in the side chain, the content thereof is preferably 1 to 30 mol%, more preferably 5 to 25 mol%, and further preferably 5 to 20 mol% with respect to all repeating units in the resin P.

The weight average molecular weight of the resin P is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, and further preferably 5,000 to 15,000 in terms of polystyrene by GPC (Gel permeation chromatography). By setting the weight average molecular weight to 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, and deterioration of developability or deterioration of film forming property due to increase in viscosity can be prevented.

The degree of dispersion (molecular weight distribution) is usually 1 to 5, preferably 1 to 3, more preferably 1.2 to 3.0, and still more preferably 1.2 to 2.0.

The content of the resin P in the chemical solution is preferably 50 to 99.9 mass%, more preferably 60 to 99.0 mass% in the total solid content.

In the chemical solution, 1 kind of the resin P may be used, or plural kinds may be used simultaneously.

Known substances can be used for other components (for example, an acid generator, a basic compound, a quencher, a hydrophobic resin, a surfactant, a solvent, and the like) contained in the chemical solution. Examples of the other components include those contained in actinic-ray-or radiation-sensitive resin compositions described in Japanese patent laid-open Nos. 2013-195844, 2016-057645, 2015-207006, 2014/148241, 2016-188385, and 2017-219818.

[ use of medicinal liquids ]

The chemical solutions of the above embodiments are used for manufacturing semiconductor devices. In particular, it is more preferable to form a fine pattern having a node of 10nm or less (for example, including a step of patterning using EUV).

The chemical solution of the above embodiment is a chemical solution (a pre-wet solution, a developing solution, a rinse solution, a solvent for a resist solution, a stripping solution, and the like) used in a resist process in which the pattern width and/or the pattern interval is 17nm or less (preferably 15nm or less, preferably 12nm or less) and/or the obtained wiring width and/or the wiring interval is 17nm or less, in other words, is more preferably used for manufacturing a semiconductor device manufactured using a resist film having a pattern width and/or a pattern interval of 17nm or less.

Specifically, in a manufacturing process of a semiconductor device including a photolithography step, an etching step, an ion implantation step, a peeling step, and the like, the organic material is treated after each step is completed or before the next step is transferred, and specifically, the organic material is preferably used as a pre-wetting liquid, a developing liquid, a rinse liquid, a peeling liquid, and the like. For example, the method can be used for rinsing the edge line of the semiconductor substrate before and after resist coating.

The chemical solution can also be used as a diluent for the resin contained in the resist solution or a solvent contained in the resist solution. Further, the dilution may be performed by other organic solvents and/or water.

The chemical solution can be used for other purposes than the production of semiconductor devices, and can also be used as a developing solution, a rinse solution, or the like for polyimide, a resist for sensors, a resist for lenses, or the like.

The chemical solution can also be used as a solvent for medical use or cleaning use. In particular, the cleaning agent can be preferably used for cleaning containers, pipes, substrates (e.g., wafers, glass, etc.), and the like.

Among them, the chemical solution exhibits more excellent effects when applied to a pre-wetting solution, a developing solution and a rinse solution in the formation of a pattern using EUV (extreme ultraviolet).

[ method for producing chemical solution ]

The method for producing the chemical solution is not particularly limited, and a known production method can be used. Among them, from the viewpoint of obtaining a chemical solution having more excellent effects of the present invention, it is preferable that the method for producing a chemical solution includes a filtration step of obtaining a chemical solution by filtering a purified product containing an organic solvent with a filter.

The purified product used in the filtration step is obtained by supplying and reacting the raw materials for purchase or the like. As the purified product, a material containing a small amount of the metal-containing particles and/or impurities described above is preferably used. Examples of commercially available products of such purified products include "high-purity grades".

The method for obtaining a purified product (typically, a purified product containing an organic solvent) by reacting the raw materials is not particularly limited, and a known method can be used. For example, a method of obtaining an organic solvent by reacting one or more kinds of raw materials in the presence of a catalyst is given.

More specifically, examples thereof include: a method for obtaining butyl acetate by reacting acetic acid with n-butanol in the presence of sulfuric acid; in Al (C)₂H₅)₃A method of obtaining 1-hexanol by reacting ethylene, oxygen and water in the presence of (a); a method in which cis-4-methyl-2-pentene is reacted in the presence of Ipc2BH (Dipinocampheylborane: Diisopinocampheylborane) to obtain 4-methyl-2-pentanol; a method of reacting propylene oxide, methanol and acetic acid in the presence of sulfuric acid to obtain PGMEA (propylene glycol 1-monomethyl ether 2-acetate); a method of obtaining IPA (isopropyl alcohol) by reacting acetone and hydrogen in the presence of copper oxide-zinc oxide-alumina; and a method for obtaining ethyl lactate by reacting lactic acid with ethanol; and the like.

< filtration Process >

The method for producing a chemical solution according to the embodiment of the present invention includes a filtering step of filtering the purified product with a filter to obtain a chemical solution. The method of filtering the purified product with the filter is not particularly limited, but the purified product is preferably passed (passed) through a filter unit having a housing and a filter cartridge housed in the housing, with or without pressurization.

Pore diameter of the filter

The pore diameter of the filter is not particularly limited, and a filter having a pore diameter generally used for filtration of a purified product can be used. Among these, from the viewpoint of more easily controlling the number of particles contained in the chemical solution, the particles having a particle diameter of 0.5 to 17nm, the pore diameter of the filter is preferably 200nm or less, more preferably 20nm or less, still more preferably 10nm or less, particularly preferably 5nm or less, and most preferably 3nm or less. The lower limit is not particularly limited, but is preferably 1nm or more in general from the viewpoint of productivity.

In the present specification, the pore diameter and pore diameter distribution of the filter mean that isopropyl alcohol (IPA) or HFE-7200 ("Novec 7200", manufactured by 3M Company, hydrofluoroether, C)₄F₉OC₂H₅) Pore diameter and pore diameter distribution determined by the bubble point (bubbleboint).

When the pore diameter of the filter is 5.0nm or less, it is preferable from the viewpoint of easier control of the number of particles contained in the chemical solution, the particles having a particle diameter of 0.5 to 17 nm. Hereinafter, a filter having a pore diameter of 5nm or less is also referred to as a "fine pore filter".

The fine pore size filter may be used alone or in combination with a filter having another pore size. Among them, from the viewpoint of further excellent productivity, it is preferable to use the filter having a larger pore diameter together with the filter. In this case, since the purified material obtained by filtering the purified material in advance through the filter having a larger pore diameter is passed through the fine pore filter, clogging of the fine pore filter can be prevented.

That is, as the pore diameter of the filter, in the case of using 1 filter, the pore diameter is preferably 5.0nm or less, and in the case of using 2 or more filters, the pore diameter of the filter having the smallest pore diameter is preferably 5.0nm or less.

The mode of sequentially using 2 or more types of filters having different pore diameters is not particularly limited, but a method of sequentially arranging the filter units described above along a pipeline through which a purified product is transported is exemplified. In this case, if the flow rate per unit time of the purified product is to be constant in the entire pipe, a larger pressure may be applied to the filter unit having a smaller pore diameter than the filter unit having a larger pore diameter. In this case, it is preferable to increase the filtration area by arranging a pressure regulating valve, a damper, and the like between the filter units so that the pressure applied to the filter unit having a small pore diameter is constant, or by arranging filter units housing the same filter in parallel along the pipe. Therefore, the number of particles contained in the chemical solution can be controlled more stably, the number of particles being 0.5 to 17 nm.

Material of the filters

The material of the filter is not particularly limited, and a known material can be used as the material of the filter. Specifically, in the case of a resin, there may be mentioned polyamides such as 6-nylon and 6, 6-nylon; polyolefins such as polyethylene and polypropylene; polystyrene; a polyimide; a polyamide-imide; poly (meth) acrylates; polyfluorocarbons such as polytetrafluoroethylene, perfluoroalkoxyethylene, perfluoroethylene-propylene copolymer, ethylene-tetrafluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, polychlorotrifluoroethylene, polyvinylidene fluoride and polyvinyl fluoride; polyvinyl alcohol; a polyester; cellulose; cellulose acetate, and the like. Among them, from the viewpoint of more excellent solvent resistance and more excellent defect suppression performance of the obtained chemical solution, at least one selected from the group consisting of nylon (among them, 6-nylon is preferable), polyolefin (among them, polyethylene is preferable), poly (meth) acrylate, and polyfluorocarbon (among them, Polytetrafluoroethylene (PTFE), Perfluoroalkoxyethylene (PFA) is preferable). These polymers can be used alone or in combination of 2 or more.

In addition to the resin, diatomaceous earth, glass, or the like may be used.

Also, the filter may be surface-treated. The method of surface treatment is not particularly limited, and a known method can be used. Examples of the surface treatment include chemical modification treatment, plasma treatment, hydrophobic treatment, coating, gas treatment, and sintering.

The plasma treatment is preferable because the surface of the filter is hydrophilized. The contact angle of water on the surface of the filter hydrophilized by the plasma treatment is not particularly limited, but the static contact angle at 25 ℃ as measured by a contact angle meter is preferably 60 ° or less, more preferably 50 ° or less, and further preferably 30 ° or less.

As the chemical modification treatment, a method of introducing an ion exchange group into the substrate is preferable.

That is, as the filter, a filter in which each of the materials mentioned above is used as a base material and an ion exchange group is introduced into the base material is preferable. Typically, a filter comprising a substrate having ion exchange groups on the surface is preferred. The surface-modified substrate is not particularly limited, and a substrate in which an ion exchange group is introduced into the polymer is preferable from the viewpoint of easier production.

Examples of the ion exchange group include a cation exchange group, a sulfonic acid group, a carboxyl group, and a phosphoric acid group, and examples of the anion exchange group include a quaternary ammonium. The method of introducing an ion-exchange group into a polymer is not particularly limited, but a method of reacting a compound having an ion-exchange group and a polymerizable group with a polymer and typically grafting the resulting product is exemplified.

The method for introducing the ion exchange group is not particularly limited, but the fiber of the resin is irradiated with ionizing radiation (α -rays, β -rays, γ -rays, X-rays, electron beams, and the like) to generate an active moiety (radical) in the resin. The irradiated resin is immersed in a monomer-containing solution to graft-polymerize the monomer and the base material. As a result, a polymer in which the monomer is bonded to the polyolefin fiber as a graft-polymerized side chain is produced. The final product is obtained by bringing a resin having the produced polymer as a side chain into contact reaction with a compound having an anion exchange group or a cation exchange group to introduce the ion exchange group to the polymer of the graft-polymerized side chain.

The filter may be a combination of a woven or nonwoven fabric having an ion-exchange group formed by radiation graft polymerization and a conventional filter material of glass wool, woven or nonwoven fabric.

When a filter having an ion exchange group is used, the content of the particles containing metal atoms in the chemical solution can be more easily controlled to a desired range. The material of the filter having an ion exchange group is not particularly limited, but examples thereof include those obtained by introducing an ion exchange group into a polyfluorocarbon and a polyolefin, and those obtained by introducing an ion exchange group into a polyfluorocarbon are more preferable.

The pore diameter of the filter having an ion exchange group is not particularly limited, but is preferably 1 to 30nm, more preferably 5 to 20 nm. The filter having the ion exchange group may be used as the filter having the minimum pore diameter described above, or may be used separately from the filter having the minimum pore diameter. Among them, from the viewpoint of obtaining a chemical solution having more excellent effects of the present invention, a mode in which a filter having an ion exchange group and a filter having no ion exchange group and having a minimum pore diameter are used together in the filtration step is preferable.

The material of the filter having the smallest pore diameter described above is not particularly limited, but from the viewpoint of solvent resistance and the like, at least one selected from the group consisting of polyfluorocarbons and polyolefins is preferable, and polyolefins are more preferable.

Further, if the material of the filter is polyamide (particularly, nylon), the content of the high-boiling organic compound and the content of the particles U in the chemical solution can be controlled more easily, and particularly, the content of the particles U in the chemical solution can be controlled more easily.

Therefore, as the filter used in the filtration step, 2 or more filters of different materials are preferably used, and more preferably 2 or more filters selected from the group consisting of polyolefins, polyfluorocarbons, polyamides, and substances obtained by introducing ion exchange groups into these.

Pore structure of the filter

The pore structure of the filter is not particularly limited, and may be appropriately selected depending on the components in the purified product. In the present specification, the pore structure of the filter means a pore diameter distribution, a position distribution of pores in the filter, a shape of the pores, and the like, and can be typically controlled by a method for manufacturing the filter.

For example, a porous film can be obtained by sintering a powder such as a resin, and a fiber film can be obtained by electrospinning, electroblowing, melt blowing, or the like. Their respective pore structures are different.

The "porous membrane" refers to a membrane in which components in a purified substance such as gel, particles, colloid, cells, and oligomer are retained, but components substantially smaller than the pores pass through the pores. The retention of components in a purified product by a porous membrane may depend on operation conditions such as surface velocity, use of a surfactant, pH, and a combination thereof, and may depend on the pore size and structure of the porous membrane and the size and structure of particles to be removed (hard particles, gel, or the like).

When the purified product contains particles U (which may be in the form of a gel) as impurities, the particles containing a high-boiling organic compound are generally negatively charged, and in order to remove such particles, the polyamide filter functions as a non-sieve membrane. Typical non-sieving membranes include nylon membranes such as nylon-6 membrane and nylon-6, 6 membrane, but are not limited thereto.

The term "non-sieve" as used herein means a mechanism that causes interference, diffusion, adsorption, and the like, regardless of the pressure drop of the filter or the pore diameter.

The non-sieve holding includes a holding mechanism for removing particles to be removed in the purified product, such as disturbance, diffusion, and adsorption, regardless of a pressure drop of the filter or a pore diameter of the filter. The adsorption of particles on the filter surface can be carried by, for example, van der waals force between molecules, electrostatic force, or the like. In the case where particles moving in a non-sieving membrane layer having a curved path cannot change direction sufficiently quickly so as not to come into contact with the non-sieving membrane, an interference effect occurs. Diffusion-based particle transport, by generating a constant probability of a particle colliding with the filter material, results mainly from irregular or brownian motion of small particles. The non-sieve holding mechanism can become active in the absence of a repulsive force between the particles and the filter.

UPE (ultra high molecular weight polyethylene) filters, typically sieve membranes. A sieving membrane refers to a membrane that primarily captures particles via a sieve holding mechanism or a membrane optimized for capturing particles via a sieve holding mechanism.

As typical examples of the sieving membrane, a Polytetrafluoroethylene (PTFE) membrane and a UPE membrane are included, but not limited thereto.

The "screen holding mechanism" refers to holding based on the result that the particles to be removed are larger than the pore diameter of the porous membrane. The screen retention can be improved by forming a cake (aggregation of particles to be removed on the surface of the membrane). The filter cake effectively performs the function of a secondary filter.

The material of the fiber layer is not particularly limited as long as it is a polymer capable of forming the fiber layer. Examples of the polymer include polyamide. Examples of the polyamide include nylon 6 and nylon 6, 6. As the polymer forming the fiber membrane, poly (ether sulfone) may be mentioned. When the fiber membrane is on the primary side of the porous membrane, the fiber membrane preferably has a higher surface energy than a polymer that is a material of the porous membrane on the secondary side. Such a combination may be, for example, a case where the material of the fiber membrane is nylon and the porous membrane is polyethylene (UPE).

The method for producing the fiber membrane is not particularly limited, and a known method can be used. Examples of the method for producing the fiber film include electrospinning, electroblowing, and melt blowing.

The pore structure of the porous membrane (for example, a porous membrane containing UPE, PTFE, and the like) is not particularly limited, but examples of the shape of the pores include a lace shape, a string shape, and a dot shape.

The pore size distribution in the porous membrane and the position distribution in the membrane are not particularly limited. It is possible that the distribution of sizes is smaller and the distribution position in the film is symmetrical. Further, the distribution of the size may be larger and the distribution position in the membrane may be asymmetric (the membrane is also referred to as an "asymmetric porous membrane"). In asymmetric porous membranes, the size of the pores varies within the membrane, typically the pore size increases from one surface of the membrane towards the other surface of the membrane. In this case, the surface on the side having a large number of pores with large pore diameters is referred to as "open side", and the surface on the side having a large number of pores with small pore diameters is referred to as "dense side".

Further, as the asymmetric porous membrane, for example, a porous membrane in which the size of pores is smallest at a certain position within the thickness of the membrane (this is also referred to as "hourglass shape").

When an asymmetric porous membrane is used and the primary side is a larger-sized pore, in other words, the primary side is an open side, a prefiltering effect can be produced.

The porous membrane may contain a thermoplastic polymer such as PESU (polyethersulfone), PFA (perfluoroalkoxyethylene, a copolymer of tetrafluoroethylene and perfluoroalkoxyethylene), polyamide, and polyolefin, or may contain polytetrafluoroethylene.

Among them, the material of the porous film is preferably ultra-high molecular weight polyethylene. Ultra-high molecular weight polyethylene refers to thermoplastic polyethylene with extremely long chains, with a molecular weight of more than a million, typically preferably 200 to 600 ten thousand.

As the filter used in the filtration step, 2 or more filters having different pore structures are preferably used, and a filter having a porous membrane and a fibrous membrane is more preferred. Specifically, a filter using a nylon fiber membrane and a filter using a UPE porous membrane are preferably used together.

As described above, the filtration step of the embodiment of the present invention is preferably a multistage filtration step in which the purified product is passed through 2 or more different filters selected from the group consisting of a material of the filter, a pore diameter, and a pore structure.

(multistage filtration Process)

The multistage filtration step can be carried out using a known purification apparatus. Fig. 1 is a schematic diagram showing a typical example of a purification apparatus capable of performing a multi-stage filtration process. The purification apparatus 10 includes a production tank 11, a filtration apparatus 16, and a filling apparatus 13, and these units are connected by a pipe 14.

The filter device 16 includes a filter unit 12(a) and a filter unit 12(b) connected by a pipe 14. A control valve 15(a) is disposed in a pipe between the filter unit 12(a) and the filter unit 12 (b).

In fig. 1, the case where the number of filter units is 2 is described, but 3 or more filter units may be used.

In fig. 1, the purified product is stored in a manufacturing tank 11. Subsequently, a pump, not shown, disposed in the pipe 14 is operated, and the purified product is sent from the production tank 11 to the filtration device 16 through the pipe 14. The direction of conveyance of the purified product in the purification apparatus 10 is indicated by F1 in fig. 1.

The filter device 16 includes a filter unit 12(a) and a filter unit 12(b) connected by a pipe 14, and filter cartridges each having at least one different filter selected from the group consisting of a pore diameter, a material, and a pore structure are housed in each of the 2 filter units. The filtering device 16 has a function of filtering the purified material supplied through the pipe with a filter.

The filter to be housed in each filter unit is not particularly limited, but a filter having the smallest pore diameter is preferably housed in the filter unit 12 (b).

The purified product is supplied to the filter unit 12(a) by the pump operation and filtered. The purified material filtered by the filter unit 12(a) is depressurized as necessary by the control valve 15(a), supplied to the filter unit 12(b), and filtered.

In addition, the purification apparatus may not have the regulating valve 15 (a). Further, even in the case of having the regulating valve 15(a), the position thereof may be not the primary side of the filter unit 12(b) but the primary side of the filter unit 12 (a).

As a device capable of adjusting the supply pressure of the purified material, a device other than the regulator valve may be used. Examples of such a member include a damper.

In the filtration device 16, each filter is formed with a filter cartridge, but the filter that can be used in the purification method of the present embodiment is not limited to the above-described embodiment. For example, the purified product may be passed through a filter formed in a flat plate shape.

The purification apparatus 10 is configured to transport the purified material after the filtration by the filter unit 12(b) to the filling apparatus 13 and store the purified material in the container, but the filtration apparatus for performing the purification method is not limited to the above, and may be configured to return the purified material filtered by the filter unit 12(b) to the manufacturing tank 11 and pass the purified material through the filter unit 12(a) and the filter unit 12(b) again. The filtration method as described above is called a loop filtration. In the purification of a purified product by the circulation filtration, at least 1 of 2 or more filters is used 2 or more times. In addition, in the present specification, the number of cycles of returning the filtered purified material filtered by each filter unit to the manufacturing tank is counted as 1.

The number of cycles may be appropriately selected based on the components in the purified product, etc.

The material of the liquid-contacting portion of the purification apparatus (which refers to the inner wall surface or the like with which the object to be purified and the chemical liquid may come into contact) is not particularly limited, but is preferably formed of at least one selected from the group consisting of a non-metallic material and an electropolished metallic material (hereinafter, these are also collectively referred to as "corrosion-resistant material"). For example, the liquid-receiving portion of the production tank is formed of a corrosion-resistant material, and examples thereof include a case where the production tank itself is formed of a corrosion-resistant material, and an inner wall surface of the production tank is covered with a corrosion-resistant material.

The non-metallic material is not particularly limited, and a known material can be used.

Examples of the non-metallic material include at least one selected from the group consisting of a polyethylene resin, a polypropylene resin, a polyethylene-polypropylene resin, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, a tetrafluoroethylene-ethylene copolymer, a chlorotrifluoroethylene-ethylene copolymer, a vinylidene fluoride resin, a chlorotrifluoroethylene copolymer, and a vinyl fluoride resin, but are not limited thereto.

The metal material is not particularly limited, and a known material can be used.

Examples of the metal material include metal materials containing chromium and nickel in an amount exceeding 25 mass% based on the total mass of the metal material, and preferably 30 mass% or more. The upper limit of the total content of chromium and nickel in the metal material is not particularly limited, but is preferably 90 mass% or less.

Examples of the metal material include stainless steel and nickel-chromium alloy.

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

The nickel-chromium alloy is not particularly limited, and a known nickel-chromium alloy can be used. Among them, a nickel-chromium alloy having a nickel content of 40 to 75 mass% and a chromium content of 1 to 30 mass% is preferable.

Examples of the nickel-chromium alloy include hastelloy (trade name, hereinafter the same), monel (trade name, hereinafter the same), inconel (trade name, hereinafter the same), and the like. More specifically, Hastelloy C-276(Ni content 63 mass%, Cr content 16 mass%), Hastelloy C (Ni content 60 mass%, Cr content 17 mass%), Hastelloy C-22(Ni content 61 mass%, Cr content 22 mass%), and the like can be given.

The nickel-chromium alloy may contain boron, silicon, tungsten, molybdenum, copper, cobalt, and the like, as necessary, in addition to the above alloys.

The method for electropolishing 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 Japanese patent laid-open No. 2015-227501 and paragraphs 0036 to 0042 of Japanese patent laid-open No. 2008-264929 can be used.

It is presumed that the metallic material has a chromium content in the passivation layer of the surface more than that of the parent phase by electropolishing. Therefore, it is presumed that when a purifying apparatus in which the liquid-contacting portion is formed of an electropolished metal material is used, the metal-containing particles in the purified material do not easily flow out.

In addition, the metal material may be polished. The polishing method is not particularly limited, and a known method can be used. The size of the polishing particles used for the finish polishing is not particularly limited, but is preferably #400 or less from the viewpoint that unevenness of the surface of the metal material is more easily reduced. In addition, polishing is preferably performed before electropolishing.

< other working procedures >

The method for producing a chemical solution according to the embodiment of the present invention is not particularly limited as long as it has a filtering step, and may have a step other than the filtering step. Examples of the step other than the filtration step include a distillation step, a reaction step, and a neutralization step.

(distillation step)

The distillation step is a step of distilling the purified product containing the organic solvent to obtain a distilled purified product. The method for distilling the purified product is not particularly limited, and a known method can be used. Typically, a method is employed in which a distillation column is disposed on the primary side of the purification apparatus described above, and the purified product after distillation is introduced into a production tank.

In this case, the liquid-receiving portion of the distillation column is not particularly limited, but is preferably formed of the corrosion-resistant material described above.

(reaction procedure)

The reaction step is a step of reacting the raw materials to produce a purified product containing an organic solvent as a reactant. The method for producing the purified product is not particularly limited, and a known method can be used. Typically, a method is mentioned in which a reaction tank is disposed on the primary side of the production tank (or distillation column) of the purification apparatus described above, and a reactant is introduced into the production tank (or distillation column).

In this case, the liquid-receiving portion of the reaction tank is not particularly limited, but is preferably formed of the corrosion-resistant material described above.

(Charge removal Process)

The neutralization step is a step of neutralizing the purified material to reduce the charge potential of the purified material.

The method of removing charges is not particularly limited, and a known method of removing charges can be used. As a method for removing the electricity, for example, a method of bringing a substance to be purified into contact with a conductive material is given.

The contact time of the purified material with 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, glassy carbon, and the like.

As a method of bringing the purified product into contact with the conductive material, for example, a method of disposing a grounded screen made of a conductive material inside the duct and passing the purified product through the screen may be mentioned.

Purification of the chemical solution, unsealing of the container attached thereto, cleaning of the container and the apparatus, storage of the solution, analysis, and the like are preferably performed in a clean room. The dust-free room is preferably the dust-free room of the international standard ISO 14644-1: a clean room having a cleanliness of class 4 or more as defined in 2015. Specifically, it preferably satisfies any one of ISO class 1, ISO class 2, ISO class 3, and ISO class 4, more preferably satisfies ISO class 1 or ISO class 2, and still more preferably satisfies ISO class 1.

The storage temperature of the chemical solution is not particularly limited, but from the viewpoint that a trace amount of impurities and the like contained in the chemical solution is less likely to be eluted, and as a result, the storage temperature is preferably 4 ℃ or higher from the viewpoint that the effect of the present invention is more excellent.

[ medicinal solution Container ]

The chemical solution produced by the above purification method can be stored in a container and stored until use.

Such a container and the chemical (or resist composition) contained in the container are collectively referred to as a chemical container. The liquid medicine is taken out from the stored liquid medicine container and used.

For the purpose of manufacturing semiconductor devices, it is preferable that the container for storing the chemical solution has high cleanliness and little elution of impurities.

Specific examples of usable containers include, but are not limited to, a series of "clean bottles" manufactured by AICELLO CHEMICAL co.

In order to prevent impurities from being mixed into the drug solution (contamination), it is also preferable to use a multilayer bottle having a 6-layer structure using 6 kinds of resins or a multilayer bottle having a 7-layer structure using 6 kinds of resins for the inner wall of the container. Examples of such containers include those described in Japanese patent laid-open publication No. 2015-123351.

The liquid-receiving portion of the container is preferably made of the corrosion-resistant material or glass described above. From the viewpoint of obtaining more excellent effects of the present invention, it is preferable that 90% or more of the area of the liquid-contacting portion is made of the material, and it is more preferable that the entire liquid-contacting portion is made of the material.