Residual metal reduction method using sequestering agents

Abstract

To provide a method for manufacturing a semiconductor material compound which can efficiently remove metal remaining in a compound using a metal sequestering agent having high solubility in a solvent.SOLUTION: A method for manufacturing a semiconductor material compound can reduce residual metal that cannot be reduced by a cation-exchange resin, and can reduce and manage to a residual metal level required for an electronic material such as a semiconductor by a process including a first process of treating a treated object containing an organic solvent, and an organic compound capable of forming a complex with metal with a metal sequestering agent and an anion-exchange resin, and a second step of filtering the treated solution with a filter.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for reducing residual metals in electronic material compounds, particularly material compounds used in semiconductor manufacturing. [Background technology]

[0002] Monomers and polymers used in the field of electronic materials, including semiconductors, require the reduction and management of residual metals on the order of ppb, and various methods for reducing residual metals are being investigated. Generally, residual metal species have a cation structure (e.g., Fe 2+ , Fe 3+ , Cr 3+ , Al 3+ , Sn 2+ , Ni 2+ , Cu 2+ These metals are reduced by ion exchange treatment using cation exchange resins.Metal reduction methods using chelating resins, in which chelating structures are supported on resins, have also been developed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2021 / 045068 Summary of the Invention [Problem to be solved by the invention]

[0004] Typically, cation exchange resins and chelate exchange resins are often used to reduce residual metals in raw materials (monomers and polymers). However, when the raw material contains many heteroatoms and the metals have already formed coordination structures with the raw material, cation exchange resins and chelate resins, which rely on physical contact, cannot easily separate the metal species from the coordination structure. This makes it difficult to reduce metals using existing technologies. Furthermore, if the structure of the target monomer or polymer changes upon contact with the cation exchange resin, the cation exchange resin cannot be used. An object of the present invention is to provide a method for producing a semiconductor material compound that can efficiently remove metals remaining in the compound by using a sequestering agent that is highly soluble in a solvent. [Means for solving the problem]

[0005] As a result of extensive research, the inventors discovered a method of reducing residual metals by using an anion exchange resin and a sequestering agent in combination, and then further reducing the residual metals by filtration through a filter, thereby completing the present invention. That is, the present invention includes the following. 1. A method for producing a semiconductor material compound from which metal impurities have been removed, comprising a first step of treating a workpiece containing an organic solvent and an organic compound capable of forming a complex with a metal with a sequestering agent and an anion exchange resin. 2. The method for producing a semiconductor material compound according to the above item 1, wherein the sequestering agent is a compound having at least two groups selected from the group consisting of a carboxy group, a hydroxy group, an amino group, a carbonyl group, a phosphonyl group, a phosphonic acid group, a sulfonyl group, a sulfonic acid group and a thiol group. 3. The method for producing a semiconductor material compound according to the above 1 or 2, wherein the sequestering agent is a compound having at least one pair of partial structures represented by the following formula (1) and formula (2) in the molecule: [ka] In formula (1), X1 and X2 each independently represent a hydroxy group, an amino group, a thiol group, a carboxy group, or a phosphonic acid group; X3 represents a carbon atom or a nitrogen atom; * represents a bond; n and m each independently represent an integer of 0 to 2; and when X3 represents a nitrogen atom, there is only one *. In formula (2), Y1 represents a carboxy group, a phosphonic acid group, or a sulfonic acid group, and * represents a bond. 4. The method for producing the semiconductor material compound according to 3 above, wherein X1 and X2 in the formula (1) represent phosphonic acid groups. 5. The method for producing a semiconductor material compound according to any one of the above items 1 to 4, wherein the sequestering agent is alkylphosphonic acid. 6. The method for producing a semiconductor material compound according to any one of items 1 to 5 above, wherein the organic compound capable of forming a complex with a metal is an aromatic compound having 6 to 40 carbon atoms and at least two hydroxyl groups or alkoxyl groups in the molecule. 7. The method for producing a semiconductor material compound according to any one of 1 to 6 above, wherein the organic compound capable of forming a complex with a metal is a compound represented by the following formula (4), or a compound in which at least two structures represented by formula (4) are linked via a spacer or a single bond between carbon atoms not substituted on the benzene ring. [ka] (In formula (4), the benzene ring may be substituted with a halogen atom, a phenyl group, or an alkyl group having 1 to 10 carbon atoms. R 11 , R 12 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; n3 is an integer of 1 to 4, n4 is an integer of 1 to (5-n3), and (n3+n4) is an integer of 2 to 5. 8. The method for producing a semiconductor material compound according to any one of 1 to 7 above, wherein the first step is a step of treating the object to be treated with a sequestering agent and then with an anion exchange resin. 9. The method for producing a semiconductor material compound according to any one of items 1 to 8 above, wherein in the first step, the treatment with the anion exchange resin is carried out in a batch system or a column flow system. 10. A method for producing a semiconductor material compound according to any one of the above items 1 to 9, wherein the metal to be removed is a divalent or trivalent metal. 11. A method for producing a semiconductor material compound according to any one of 1 to 10 above, wherein the concentrations of Al, Cr, Mn, Fe, Ni, Cu and Sn in the semiconductor material compound from which metal impurities have been removed are each 10 ppb or less. 12. A method for producing a semiconductor material compound according to any one of items 1 to 11 above, further comprising a second step of filtering the treatment liquid obtained in the first step through a filter. [Effects of the Invention]

[0006] According to the present invention, in the production of semiconductor material compounds, residual metals that could not be reduced by cation exchange resins can be reduced, and the residual metal levels in the compounds can be reduced and controlled to the residual metal levels required for electronic materials such as semiconductors. DETAILED DESCRIPTION OF THE INVENTION

[0007] The present invention provides a method for producing a semiconductor material compound from which metal impurities have been removed, comprising a first step of treating a workpiece containing an organic solvent and an organic compound capable of forming a complex with a metal, with a sequestering agent and an anion exchange resin.

[0008] [Sequestering agent] The sequestering agent used in the present invention is not particularly limited as long as it is a compound that forms a complex with a metal, and examples thereof include compounds having at least two groups selected from the group consisting of a carboxy group, a hydroxy group, an amino group, a carbonyl group, a phosphonyl group, a phosphonic acid group, a sulfonyl group, a sulfonic acid group, and a thiol group.

[0009] Further, the sequestering agent may have at least one pair of partial structures represented by the following formula (1) and formula (2) in the molecule. [ka] In formula (1), X1 and X2 each independently represent a hydroxy group, an amino group, a thiol group, a carboxy group, or a phosphonic acid group, X3 represents a carbon atom or a nitrogen atom, * represents a bond, and n and m each independently represent an integer of 0 to 2, and when X3 represents a nitrogen atom, there is only one *. In formula (2), Y1 represents a carboxy group, a phosphonic acid group, or a sulfonic acid group, and * represents a bond.

[0010] More specifically, alkylphosphonic acids and alkylcarboxylic acids are included.

[0011] Examples of alkylphosphonic acids include alkylphosphonic acids and salts thereof. The alkyl group of the alkylphosphonic acid may have a structure substituted with a hydroxy group or an amino group. In addition, dimerized di(alkylphosphonic acid) or a salt thereof, or trimerized tri(alkylphosphonic acid) or a salt thereof may be used. Examples of the salt include sodium salt, potassium salt, and ammonium salt.

[0012] Examples of the alkylphosphonic acid include 1-hydroxyethane-1,1-diphosphonic acid, nitrilotris(methylenephosphonic acid), N,N,N',N'-ethylenediaminetetrakis(methylenephosphonic acid), methylenediphosphonic acid, aminomethylphosphonic acid, and salts thereof.

[0013] Examples of alkylcarboxylic acids include EDTA (ethylenediaminetetraacetic acid), NTA (nitrilotriacetic acid), DTPA (diethylenetriaminepentaacetic acid), HEDTA (N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid), TTHA (triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetic acid), PDTA (1,3-propanediamine-N,N,N',N'-tetraacetic acid), DPTA-OH(1 ,3-diamino-2-hydroxypropane-N,N,N',N'-tetraacetic acid), HIDA (N-(2-hydroxyethyl)iminodiacetic acid), DHEG (N,N-di(2-hydroxyethyl)glycine), GEDTA (glycol ether diamine tetraacetic acid), CMGA (L-glutamic acid diacetate tetrasodium), EDDS (ethylenediamine-N,N'-disuccinic acid), and salts thereof. The following formulas (5-1) to (5-12) are the chemical formulas of the alkylcarboxylic acids.

[0014] [ka]

[0015] Preferably, X1 and X2 in formula (1) are phosphonic acid groups and the sequestering agent is an alkylphosphonic acid.

[0016] A mixed solution containing a sequestering agent at a concentration of about 1 to 50,000 ppm, or 10 to 10,000 ppm, or 100 to 5,000 ppm in a solution in which the monomer is dissolved can be added to the reaction system.

[0017] [Organic compound capable of forming a complex with a metal] (compound to be purified) In the present invention, the organic compound capable of forming a complex with a metal (also referred to as the compound to be purified) has in its molecule It is an organic compound that has multiple heteroatoms and can form complexes with metals.

[0018] Such compounds include low-molecular-weight compounds and high-molecular-weight compounds, but low-molecular-weight compounds are preferred from the viewpoint of dissolving them in a solvent during the purification process. A low-molecular-weight compound is one with a molecular weight of 1,000 or less.

[0019] Examples of such compounds include nitrogen-containing compounds such as hydantoin compounds, barbituric acid compounds, and isocyanuric acid compounds, alkoxysilicon compounds, and aromatic compounds having an alkoxyl group or an alkoxymethyl group in the molecule. Among these, aromatic compounds having 6 to 40 carbon atoms and having at least two or more hydroxyl groups or alkoxyl groups in the molecule are preferred.

[0020] Examples of hydantoin compounds include hydantoin, 5,5-diphenylhydantoin, 5,5-dimethylhydantoin, 5-ethylhydantoin, 5-benzylhydantoin, 5-ethyl-5-phenylhydantoin, 5-methylhydantoin, 5,5-tetramethylenehydantoin, 5,5-pentamethylenehydantoin, 5-(4-hydroxybenzyl)-hydantoin, 5-phenylhydantoin, 5-hydroxymethylhydantoin, and 5-(2-cyanoethyl)hydantoin. Also, 1,3-diglycidylhydantoin, 1,3-diglycidyl-5,5-diphenylhydantoin, 1,3-diglycidyl-5,5-dimethylhydantoin, 1,3-diglycidyl-5-methylhydantoin, 1,3-diglycidyl-5-ethyl-5-phenylhydantoin, 1,3-diglycidyl-5-benzylhydantoin, 1,3-diglycidyl-5-hydantoin acetic acid, 1,3-diglycidyl-5-ethyl-5-methylhydantoin, 1, 3-diglycidyl-5-ethylhydantoin, 1,3-diglycidyl-5,5-tetramethylenehydantoin, 1,3-diglycidyl-5,5-pentamethylenehydantoin, 1,3-diglycidyl-5-(4-hydroxybenzyl)hydantoin, 1,3-diglycidyl-5-phenylhydantoin, 1,3-diglycidyl-5-hydroxymethyl-hydantoin, and 1,3-diglycidyl-5-(2-cyanoethyl)hydantoin.

[0021] Examples of barbituric acid compounds include barbituric acid, 5,5-dimethylbarbituric acid, 5,5-diethylbarbituric acid (also known as barbital), 5-methyl-5-ethylbarbituric acid, 5,5-diallylbarbituric acid (also known as allobarbital), 5-ethyl-5-phenylbarbituric acid (also known as phenobarbital), 5-ethyl-5-isopentylbarbituric acid (also known as amobarbital), 5,5-diallylmalonylurea, 5-ethyl-5-isoamylbarbituric acid, and 5-allyl-5-isobutyric acid. arylbarbituric acid, 5-allyl-5-isopropylbarbituric acid, 5-β-bromoallyl-5-sec-butylbarbituric acid, 5-ethyl-5-(1-methyl-1-butenyl)barbituric acid, 5-isopropyl-5-β-bromoallylbarbituric acid, 5-(1-cyclohexyl)-5-ethylmalonylurea, 5-ethyl-5-(1-methylbutyl)malonylurea, 5,5-dibromobarbituric acid, 5-phenyl-5-ethylbarbituric acid, and 5-ethyl-5-normal-butylbarbituric acid. Also, 1,3-diglycidyl-5,5-diethylbarbituric acid, 1,3-diglycidyl-5-phenyl-5-ethylbarbituric acid, 1,3-diglycidyl-5-ethyl-5-isoamylbarbituric acid, 1,3-diglycidyl-5-allyl-5-isobutylbarbituric acid, 1,3-diglycidyl-5-allyl-5-isopropylbarbituric acid, 1,3-diglycidyl-5-β-bromoallyl-5-sec-butylbarbituric acid, 1,3-diglycidyl-5-ethyl-5-(1-methyl-1-butenyl)barbituric acid, 1,3-diglycidyl-5-isopropyl-5-β-bromoallylbarbituric acid, 1,3-diglycidyl-5-(1-cyclohexyl)-5-ethylmalonylurea, 1,3-diglycidyl Examples include glycidyl-5-ethyl-5-(1-methylbutyl)malonylurea, 1,3-diglycidyl-5,5-diallylmalonylurea diglycidyl, and 1,3-diglycidyl-5-ethyl-5-normal butylbarbiturate.

[0022] Examples of the isocyanuric acid compound include monoallyl isocyanuric acid, monomethyl isocyanuric acid, monoethyl isocyanuric acid, monopropyl isocyanuric acid, monoisopropyl isocyanuric acid, monophenyl isocyanuric acid, monobenzyl isocyanuric acid, and monochloroisocyanuric acid. Further examples include monoallyl diglycidyl isocyanuric acid, monomethyl diglycidyl isocyanuric acid, monoethyl diglycidyl isocyanuric acid, monopropyl diglycidyl isocyanuric acid, monomethylthiomethyl diglycidyl isocyanuric acid, monoisopropyl diglycidyl isocyanuric acid, monomethoxymethyl diglycidyl isocyanuric acid, monobutyl diglycidyl isocyanuric acid, monomethoxyethoxymethyl diglycidyl isocyanuric acid, monophenyl diglycidyl isocyanuric acid, monobromo diglycidyl isocyanuric acid, monoallyl isocyanuric acid diglycidyl ester, and monomethyl isocyanuric acid diglycidyl ester.

[0023] Examples of the alkoxy silicon compound include the following: [ka]

[0024] [ka] [ka] [ka] [ka]

[0025] Examples of aromatic compounds having an alkoxyl group or an alkoxymethyl group in the molecule include a compound represented by the following formula (4), or a compound in which at least two structures represented by formula (4) are linked by a spacer or a single bond between carbon atoms not substituted on the benzene ring.

[0026] [ka] The benzene ring may be substituted with a halogen atom, a phenyl group, or an alkyl group having 1 to 10 carbon atoms. 11 , R 12 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. n3 is an integer of 1 to 4, n4 is an integer of 1 to (5-n3), and (n3+n4) is an integer of 2 to 5. An example of a spacer is -(CH2) n -(n=1~20), -C(CH3)2-, -C(CH3)2-Ph-C(CH3)2-(Ph=C6H4), TIFF0007800790000011.tif1442 and TIFF0007800790000012.tif1447 or a combination of two or more thereof. Two or more of these spacers may be linked together. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, a cyclobutyl group, a 1-methyl-cyclopropyl group, a 2-methyl-cyclopropyl group, an n-pentyl group, a 1-methyl-n-butyl group, a 2-methyl-n-butyl group, a 3-methyl-n-butyl group, a 1,1-dimethyl-n-propyl group, a 1,2-dimethyl-n-propyl group, a 2,2-dimethyl-n-propyl group, a 1-ethyl-n-propyl group, Cyclopentyl, 1-methylcyclobutyl, 2-methylcyclobutyl, 3-methylcyclobutyl, 1,2-dimethylcyclopropyl, 2,3-dimethylcyclopropyl, 1-ethylcyclopropyl, 2-ethylcyclopropyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl, 1,2-dimethyl-n-butyl, 1,3-dimethyl-n-butyl, 2,2- Dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group, 3 -ethyl-cyclobutyl, 1,2-dimethyl-cyclobutyl, 1,3-dimethyl-cyclobutyl, 2,2-dimethyl-cyclobutyl, 2,3-dimethyl-cyclobutyl, 2,4-dimethyl-cyclobutyl, 3,3-dimethyl-cyclobutyl, 1-n-propyl-cyclopropyl, 2-n-propyl-cyclopropyl, 1-i-propyl-cyclopropyl, 2-i-propyl-cyclopropyl, 1,2,2-trimethyl-cyclopropyl, 1,2,3-trimethyl-cyclopropyl, 2,2,Examples include 3-trimethyl-cyclopropyl, 1-ethyl-2-methyl-cyclopropyl, 2-ethyl-1-methyl-cyclopropyl, 2-ethyl-2-methyl-cyclopropyl, and 2-ethyl-3-methyl-cyclopropyl groups. Among these, R 11 , R 12 is preferably a hydrogen atom or a methyl group.

[0027] Examples of compounds represented by formula (4) or compounds in which at least two structures represented by formula (4) are linked via a spacer or a single bond between unsubstituted carbon atoms on the benzene rings are shown below. [ka]

[0028] [ka]

[0029] [solvent] In the production method of the present invention, known organic solvents can be used. The organic solvent may be used without any particular limitation as long as it can dissolve the target monomer, but considering compatibility with the hydrophilic ion exchange resin, alcohol-based solvents are preferred. Specific examples thereof include methanol, ethanol, butanol, 1-propanol, 2-propanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, and propylene glycol propyl ether. Acetate, acetonitrile, toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, cyclopentyl methyl ether, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, lactic acid Examples of suitable solvents include ethyl ether, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, n-heptane, hexane, isopropyl ether, diisobutyl ether, diisoamyl ether, tert-butyl methyl ether, cyclopentyl methyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, dioxane, and 4-methyltetrahydropyran.

[0030] Among these solvents, methanol, ethanol, butanol, 1-propanol, 2-propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, etc. are preferred in the present invention, with propylene glycol monomethyl ether and propylene glycol monoethyl ether being particularly preferred.

[0031] The amount of organic solvent used is not particularly limited as long as it is an amount that can sufficiently dissolve the target monomer, but is about 1 to 100 parts by mass, preferably 1 to 20 parts by mass, relative to the target monomer.

[0032] The treatment temperature (internal temperature) is preferably −20 to 130° C., more preferably 20 to 100° C., at which the sequestering agent does not decompose and the target monomer can be sufficiently dissolved. Reflux may also be performed during heating.

[0033] The treatment time cannot be generally determined because it depends on the temperature and raw materials, but it is usually about 1 to 30 hours, and generally about 1 to 8 hours.

[0034] [Anion exchange resin] The mechanism of action of the anion exchange resin of the present invention is not to adsorb the metal, but to adsorb the sequestering agent that has captured the metal.

[0035] An example of an ion exchange resin is one in which ion exchange groups are immobilized on the surface of a porous support made of a styrene-divinylbenzene copolymer. Resins are classified as strongly basic, weakly basic, or other types depending on the type of immobilized exchange group. Strongly basic resins include quaternary ammonium groups. Weakly basic resins include tertiary groups. Furthermore, based on the physical properties of the support, they are classified as gel-type or micro-reticular (MR) type, in which pores are formed in the gel-type resin to make it porous.

[0036] The catalytic activity of an ion exchange resin depends on the contact area between the reactant and the ion exchange resin surface and the type of functional group on the ion exchange resin surface. Gel-type ion exchange resins generally have only micropores (pore diameter: several tens of Å to several tens of Å), so it is expected that reactants with large molecular weights, such as polymers, will have difficulty penetrating into the resin pores. MR-type ion exchange resins have mesopores and macropores (pore diameter: several hundred Å or more), so even reactants with large molecular weights, such as polymers, can penetrate into the pores, and it is expected that the contact area between the polymer and the ion exchange resin surface will be relatively large. The ion exchange resin used in the present invention is preferably a gel-type strongly basic ion exchange resin having quaternary ammonium groups.

[0037] There are no particular limitations on the ion exchange resin as long as it has this characteristic, and commercially available ion exchange resins can be used.

[0038] The removal of the sequestering agent that has captured the metal impurities with the ion exchange resin is carried out by reacting a solution (processed product) in which the target monomer (compound to be purified) is dissolved with the sequestering agent, and then further treating the processed product with the ion exchange resin in a batch or column flow manner. The batch method is a method in which the material to be treated and ion exchange resin are mixed and stirred for a certain period of time, and then the resin is removed by filtration, etc. The column flow method is a method in which metal impurities are removed from the material to be treated by passing the material through a fixed bed such as a column or packed tower filled with ion exchange resin.

[0039] The treatment is usually performed once, but may be performed two or more times. The treatment time in the batch process varies depending on the type and amount of the compound to be purified, the ion exchange resin, and the solvent used. Similarly, the liquid flow rate in the column flow process varies depending on the type and amount of the compound to be purified, the ion exchange resin, and the solvent used.

[0040] The anion exchange resin used in the present invention can also achieve a similar reduction effect when used in combination with a cation exchange resin, but if the structure of the target monomer or polymer changes upon contact with the cation exchange resin, it is preferable not to use a cation exchange resin.

[0041] Filter The filter used as needed in the present invention is not particularly limited, as it captures the coordinated and precipitated metal. For example, a filter having a pore size in the range of 0.001 to 1 μm and made of polyester (PE), polypropylene (PP), PTFE, or nylon can be used.

[0042] [Method for manufacturing semiconductor material compounds that remove metal impurities] The method of the present invention for producing a semiconductor material compound from which metal impurities are removed includes a first step of treating a material to be treated with a sequestering agent and an anion exchange resin. The first step is divided into two steps: contacting the material to be treated with a sequestering agent, capturing residual metals in the material with the sequestering agent, and adsorbing the sequestering agent that has captured the metals onto an anion exchange resin. The order of these steps is not limited. For example, the residual metals can be sufficiently removed by first adsorbing the sequestering agent onto the anion exchange resin and then capturing the residual metals in the material to be treated. The order in which the sequestering agent captures the residual metals first and then the anion exchange resin adsorbs them can efficiently remove the residual metals. In this first step, by treating with an anion exchange resin and a sequestering agent, metal ions are captured and residual metals are significantly reduced. Furthermore, as long as the above-mentioned mechanism of action is not significantly prevented and the effect of reducing residual metals is not significantly affected, it is also possible to treat in the presence of a cation exchange resin in addition to the anion exchange resin. Similarly, the order in which the sequestering agent and the two types of exchange resins are used is not limited.

[0043] Furthermore, as a second step, the solution treated in the first step is filtered through a filter as needed. Filter filtration may be repeated as many times as needed. It is also possible to use a filter in combination.

[0044] There is no limitation on the metals to be removed in the present invention, but considering that they are removed by forming a coordination structure with a sequestering agent, divalent or trivalent metals are efficiently removed. The amount of residual metals (e.g., Al, Cr, Mn, Fe, Ni, Cu, and Sn) remaining after treatment is preferably 10 ppb or less. The amount of residual metals can be measured, for example, by inductively coupled plasma mass spectrometry (ICP-MS) as described in the Examples. [Example]

[0045] ICP-MS: Agilent 8800, manufactured by Agilent Technologies

[0046] Example 1 In a 200 mL flask, 10.0 g of tetramethylol bisphenol A (manufactured by Asahi Organic Chemicals Co., Ltd.) (hereinafter referred to as TM-BIP-A) and 60 g of propylene glycol monomethyl ether were added. 0.0g of 1-hydroxyethane-1,1-diphosphonic acid (60% aqueous solution) (Tokyo Chemical Industry Co., Ltd.) was added and stirred at 55-60°C for 1 hour. After stirring at 55-60°C for an hour, 10.0g of anion exchange resin (ESG4002-OH) (Organo Corporation) was added and stirred at 55-60°C for an additional hour. After cooling to room temperature, the resulting solution was filtered through a 0.1µm pore membrane filter and subjected to residual metal analysis by ICP-MS. The solution before filtration through the 0.1µm membrane filter was also subjected to residual metal analysis by ICP-MS.

[0047] <Example 2> A 200 mL flask was charged with 10.0 g of TM-BIP-A (Asahi Organic Chemicals), 60.0 g of propylene glycol monomethyl ether, and 82 μL of 1-hydroxyethane-1,1-diphosphonic acid (60% aqueous solution) (Tokyo Chemical Industry Co., Ltd.). The mixture was stirred at 55–60°C for 1 hour. After stirring, 10.0 g of anion exchange resin (ESG4002-OH) (Organo Corporation) and 60.0 g of cation exchange resin (Orlite DS-4) (Organo Corporation) were added and stirred for an additional 4 hours at 55–60°C. After cooling to room temperature, the resulting solution was filtered through a 0.1 μm pore membrane filter and subjected to residual metal analysis by ICP-MS. The solution before filtration through the 0.1 μm membrane filter was also subjected to residual metal analysis by ICP-MS.

[0048] <Comparative Example 1> A 200 mL flask was charged with 10.0 g of TM-BIP-A (Asahi Organic Chemicals), 60.0 g of propylene glycol monomethyl ether, and 82 μL of 1-hydroxyethane-1,1-diphosphonic acid (60% aqueous solution) (Tokyo Chemical Industry Co., Ltd.). The mixture was stirred at 55-60°C for 1 hour and then for an additional hour. After cooling to room temperature, the resulting solution was filtered through a 0.1 μm membrane filter and subjected to residual metal analysis by ICP-MS. The solution before filtration through the 0.1 μm membrane filter was also subjected to residual metal analysis by ICP-MS.

[0049] <Comparative Example 2> A 200 mL flask was charged with 10.0 g of TM-BIP-A (Asahi Organic Chemicals) and 60.0 g of propylene glycol monomethyl ether, and the mixture was stirred at 55-60°C for 1 hour. After stirring, 10.0 g of anion exchange resin (ESG4002-OH) (Organo Corporation) was added, and the mixture was stirred at 55-60°C for an additional 1 hour. After cooling to room temperature, the resulting solution was filtered through a 0.1 μm membrane filter and subjected to residual metal analysis by ICP-MS. The solution before filtration through the 0.1 μm membrane filter was also subjected to residual metal analysis by ICP-MS.

[0050] <Comparative Example 3> 10.0 g of TM-BIP-A (manufactured by Asahi Organic Chemicals Co., Ltd.), 60.0 g of propylene glycol monomethyl ether, and 60.0 g of cation exchange resin Orlite DS-4 (manufactured by Organo Corporation) were added to a 200 mL flask and stirred for 8 hours at 55-60° C. After cooling to room temperature, the resulting solution was subjected to residual metal analysis by ICP-MS.

[0051] [Table 1]

Claims

1. A method for producing a semiconductor material compound from which metal impurities have been removed, the method comprising: a first step of treating a workpiece containing an organic solvent and an organic compound capable of forming a complex with a metal with a sequestering agent, and then treating the workpiece with an anion exchange resin, the first step comprising: the organic solvent is methanol, ethanol, butanol, 1-propanol, 2-propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, propylene glycol monomethyl ether, or propylene glycol monoethyl ether; The organic compound capable of forming a complex with a metal is a compound represented by the following formula (4), or a compound in which at least two structures represented by the formula (4) are linked via a spacer or a single bond between carbon atoms not substituted on the benzene rings: 【Chemistry 1】 In formula (4), the benzene ring may be substituted with a halogen atom, a phenyl group, or an alkyl group having 1 to 10 carbon atoms. １１ , R １２ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; n3 is an integer of 1 to 4; n4 is an integer of 1 to (5-n3); and (n3+n4) is an integer of 2 to 5. The sequestering agent is a compound having at least one pair of partial structures represented by the following formula (1) and formula (2) in the molecule: Methods for producing semiconductor material compounds. 【Chemistry 2】 (In formula (1), X １ , X ２ each independently represents a hydroxy group, a carboxy group, or a phosphonic acid group; X ３ represents a carbon atom or a nitrogen atom, * represents a bond, n and m are each independently an integer of 0 to 2, and X ３ When represents a nitrogen atom, there is only one *. In formula (2), Y １ represents a phosphonic acid group, and * represents a bond.

2. X in the formula (1) １ and X ２ The method for producing a semiconductor material compound according to claim 1 , wherein represents a phosphonic acid group.

3. 3. The method for producing a semiconductor material compound according to claim 1, wherein the sequestering agent is an alkylphosphonic acid.

4. 4. The method for producing a semiconductor material compound according to claim 1, wherein the organic compound capable of forming a complex with a metal is an aromatic compound having 6 to 40 carbon atoms and having at least two hydroxyl groups or alkoxyl groups in the molecule.

5. 5. The method for producing a semiconductor material compound according to claim 1, wherein the treatment with the anion exchange resin in the first step is carried out in a batch system or a column flow system.

6. 6. The method for producing a semiconductor material compound according to claim 1, wherein the metal to be removed is a divalent or trivalent metal.

7. 7. The method for producing a semiconductor material compound according to claim 1, wherein the semiconductor material compound from which metal impurities have been removed has concentrations of Al, Cr, Mn, Fe, Ni, Cu and Sn of 10 ppb or less.

8. The method for producing a semiconductor material compound according to any one of claims 1 to 7, further comprising a second step of filtering the treated liquid obtained in the first step with a filter.

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