KR20240037607A - Preparation and purification method of high purity methyl 2-hydroxyisobutyrate for euv semiconductor process - Google Patents

Abstract

The present invention includes the steps of producing methyl 2-hydroxyisobutyrate using 2-hydroxyisobutyric acid as an intermediate, removing salt and moisture from the methyl 2-hydroxyisobutyrate, and removing salt and moisture from the methyl 2-hydroxyisobutyrate. Disclosed is a method for producing and purifying high purity methyl 2-hydroxyisobutylate for EUV semiconductor processing, including the step of distilling the methyl 2-hydroxyisobutyrate.

Description

Manufacturing and purification method of high purity methyl 2-hydroxyisobutyrate for EUV semiconductor process {PREPARATION AND PURIFICATION METHOD OF HIGH PURITY METHYL 2-HYDROXYISOBUTYRATE FOR EUV SEMICONDUCTOR PROCESS}

The present invention relates to a method for producing and purifying high-purity methyl 2-hydroxyisobutylate for EUV semiconductor processes, and more specifically, to high-purity methyl 2-hydroxyisobutylate for semiconductor processes used in semiconductor processes, especially EUV photoresist processes. It relates to the production and purification method of butyrate.

Fine circuit patterns, such as semiconductor and display integrated circuits, are made by uniformly applying a photoresist containing a photosensitive compound and solvent to a conductive metal film or oxide film formed on a substrate by a rotary coating method, followed by exposure, development, etching, and peeling processes. It is manufactured through a method that implements the desired microcircuit pattern.

As semiconductor patterns become more refined, the purity and impurity content of chemicals used in the entire process become very important. In particular, the exposure process, which is a follow-up process to the photo process, is implemented by finely exposing the desired pattern to the coating film using short-wavelength light in the ultraviolet region, so it is very sensitive to external and internal contamination.

Therefore, when applying photoresist to a wafer, unnecessary photoresist residue and other contaminants applied to the edge or back of the substrate must be removed as they can become fatal sources of contamination in the subsequent exposure process. To remove these contaminants, thinner has long been used in the EBR (edge bead removal) process.

Recently, as the integration of semiconductors increases, fine pattern manufacturing technology has become essential, and short-wavelength ArF light sources or extreme ultraviolet (EUV) light sources are being applied to photoresist use processes, and the impact of photoresist usage on semiconductor manufacturing costs. As this has grown significantly, there has been a continued demand to reduce the amount of photoresist used to reduce costs.

In response to this requirement, the surface of the substrate is first treated with a thinner before applying the photoresist, so that the photoresist can be evenly applied to the entire surface of the substrate using only a small amount of photoresist (RRC (reducing resist consumption)). The process has been applied. The importance of the RRC process is increasing as the diameter of the substrate (wafer) increases along with the increase in integration, so the development of a thinner that can sufficiently proceed with the existing EBR process and has high RRC efficiency is required.

Photoresist thinner (PR Thinner) compositions used in these RRC and EBR processes include PGME (Propylene Glycol Monomethyl Ether), PGMEA (Propylene Glycol Monomethyl Ether Acetate), EEP (Ethyl 3-ethoxypropionate), and HBM (Methyl 2- It contains ingredients such as hydroxyisobutylate or Methyl 2-hydroxy-2-methyl propionate), and among these, methyl 2-hydroxyisobutylate (hereinafter also referred to as HBM) is one of the essential ingredients.

Materials used in semiconductor processes, especially photoresist processes using ArF or EUV light sources, have very stringent requirements in terms of purity, moisture, acidity, and metal content. For example, semiconductor-grade HBM is required to have a purity of 99.99% or more, an acidity of 20 ppm or less, and a moisture content of 50 ppm or less.

If the acid content remaining in the methyl 2-hydroxyisobutyrate used before and after photoresist application in the photolithography process is high, it affects the decomposition and curing speed of the photoresist resin, and KOH used as a developer. , it may react with water-soluble alkaline solutions such as TMAH, which may cause chip defects and may corrode semiconductor equipment.

Therefore, in order to minimize the impact on the precision of the pattern formation process in the photoresist process, it is important to purify methyl 2-hydroxyisobutyrate to a high purity that can be used in the semiconductor process and at the same time minimize the remaining acid content. very important.

Republic of Korea open patent patent 1999-0077617 (published on October 25, 1999) US 5,068,399 (published on November 26, 1991)

The present invention uses low-cost acetone as a starting material and produces methyl 2-hydroxyisobutyrate through a highly reactive 2-hydroxyisobutyric acid intermediate, followed by extraction and distillation processes to produce semiconductor grade. The purpose is to provide a method for producing and purifying high-purity methyl 2-hydroxyisobutyrate for possible EUV semiconductor processes.

According to one aspect of the present invention, preparing methyl 2-hydroxyisobutyrate according to the following reaction formula, removing salt and moisture from the methyl 2-hydroxyisobutyrate, and removing the salt and moisture from the methyl 2-hydroxyisobutyrate Provided is a method for producing and purifying high purity methyl 2-hydroxyisobutylate for EUV semiconductor processing, including the step of distilling methyl 2-hydroxyisobutyrate.

In the step of producing methyl 2-hydroxyisobutyrate, a heterogeneous solid catalyst is used together with an acid catalyst. The acid catalyst may be one or more selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, and hydrochloric acid, and the heterogeneous solid catalyst is One or more may be selected from the group consisting of strongly acidic cation exchange resin, polyvinyl sulfonic acid-grafted polystyrene, silica-sulfuric acid, silica-hypochlorous acid, sulfated zirconium, borated zirconium, and aluminum-polyphosphoric acid. Preferably, the inorganic acid and heterogeneous solid phase catalyst may be used in a total amount of 3 equivalents or more.

The step of removing the salt and moisture may be a step of extracting the methyl 2-hydroxyisobutyrate using an extractant, wherein an organic solvent such as dichloromethane, dichloroethane, dichloropropane, dichlorobutane, etc. is used as the extractant. can be used

Preferably, before the distillation step, the step of removing the acid by passing the methyl 2-hydroxyisobutyrate from which salts and moisture have been removed may be further included through Na ₂ CO ₃ or NaHCO ₃ .

In addition, the step of removing metal or particles by passing the methyl 2-hydroxyisobutyrate obtained through the distillation step through a filter may be further included.

In the step of producing methyl 2-hydroxyisobutyrate, the reaction conversion rate for each reaction step may be 90% or more, 90 to 99% or more, 95 to 99% or more, and 97 to 99% or more, respectively.

It is preferable to add an antioxidant in the distillation step. At this time, the antioxidants are BHT (Butylated hydroxyanisole), MeHQ (Hydroquinone monomethylether), TBC (4-tert.-Butylcatechol), HQ (Hydroquinone), Songnox 1010, Songnox 1076, Songnox 1135, Songnox 2450, Songnox 1035, Tris (2) , 4-di-tert-butylphenyl) phosphite ((2,4-di-tert-butylphenyl) phosphite)), and bis (2,4-di-tert-butylphenyl) pentaerythritol depot Spite ((bis(2,4-di-tert-butylphenyl pentaerythritol diphosphate)) may be selected from the group consisting of one or more.

The distillation step may include removing impurities with a boiling point lower than methyl 2-hydroxyisobutylate and removing impurities with a boiling point higher than methyl 2-hydroxyisobutylate.

Methyl 2-hydroxyisobutyrate obtained through the distillation step can be used as a thinner in a photoresist process of a semiconductor process, and the semiconductor process may include a process using an EUV light source or an ArF light source.

According to the present invention, methyl 2-hydroxyisobutyrate is manufactured from a highly reactive 2-hydroxyisobutyric acid intermediate using industrial acetone and sodium cyanide, and then the final product is produced through extraction and distillation processes. By doing so, it is possible to provide a method for manufacturing and purifying high-purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, which has excellent price competitiveness and can improve the productivity of semiconductors by lowering the defect rate even when used in the semiconductor manufacturing process.

Figure 1 is a gas chromatogram of high purity methyl 2-hydroxy isobutylate prepared and purified according to an example of the present invention.
Figure 2 is an NMR chart of methyl 2-hydroxy isobutylate prepared and purified according to an example of the present invention.

In describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

Hereinafter, an embodiment of the present invention will be described in detail.

According to one embodiment of the present invention, the present invention includes the steps of preparing methyl 2-hydroxyisobutylate, extracting the methyl 2-hydroxyisobutylate with an extractant, and extracting the extracted methyl 2-hydroxyisobutyl. and distilling the rate.

At this time, the methyl 2-hydroxyisobutyrate (hereinafter also referred to as HBM) is prepared according to the following reaction formula.

HBM according to the present invention can be prepared in three steps as shown in the above reaction scheme. That is, the HBM according to the present invention is a first step of producing acetone cyanohydrin by reacting acetone with sodium cyanide under an acid catalyst, and hydrolyzing the acetone cyanohydrin under an acid catalyst to produce 2-hydroxy isobutyric acid (2-hydroxy It can be produced by a second step of producing isobutyric acid (hereinafter referred to as HBA) and a third step of producing HBM by reacting HBA with methanol in an acid catalyst.

First, looking at the first step, production costs can be reduced by using low-cost acetone as a starting material, which is very advantageous for mass production.

Sodium cyanide is used after dissolving in 2 to 5 times the weight ratio of water, and based on 1 equivalent of NaCN, 1 to 3 equivalents of acetone can be used, preferably 1 to 1.5 equivalents.

As the acid catalyst, one or more inorganic acids selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, and hydrochloric acid may be used. At this time, when only one type of inorganic acid is used, the viscosity is high at 500 to 1500 cps, making smooth stirring difficult, resulting in a local reaction temperature difference, resulting in a low reaction conversion rate and the generation of many impurities.

Therefore, in the present invention, a heterogeneous solid phase catalyst is used together with an inorganic acid to solve the viscosity problem and increase the reaction conversion rate.

The heterogeneous solid phase catalyst may be selected from the group consisting of strongly acidic cation exchange resin, polyvinyl sulfonic acid-grafted polystyrene, silica-sulfuric acid, silica-hypochlorous acid, sulfated zirconium, borated zirconium, and aluminum-polyphosphoric acid. You can.

Based on 1 equivalent of acetone, 0.1 to 5 equivalents of inorganic acid, preferably 0.5 to 3 equivalents, are used, and 1 to 5 equivalents, preferably 1 to 3 equivalents of heterogeneous solid catalyst are used. The inorganic acid and heterogeneous solid catalyst are used together. It is preferable to use 3 equivalents or more.

In this way, when more than 3 equivalents of an inorganic acid and a heterogeneous solid phase catalyst, such as sulfuric acid and a strongly acidic cation exchange resin, are used, the viscosity is greatly improved, stirring becomes smooth, and the reaction conversion rate also improves to 95% or more.

Next, the second step of producing HBA (2-hydroxy isobutyric acid) by hydrolyzing acetone cyanohydrin under an acid catalyst will be described.

When acetone cyanohydrin is hydrolyzed under an acid catalyst, an amide compound may be produced depending on the equivalent weight of the acid used. For example, when about 1 equivalent of acid is used per equivalent of acetone cyanohydrin, amide compounds such as α-hydroxyisobutyric acid amide are mainly produced, and when about 1.5 equivalents of acid are used, a mixture of amide compounds and HBA is produced. When more than 2 equivalents of acid is used, HBA is mainly produced.

In the prior art, it is disclosed that amide compounds are mainly produced in the second step, but amide compounds are much less reactive than HBA and are therefore unsuitable for industrial mass production.

Therefore, in the present invention, in the step of producing HBM, the reaction conditions are adjusted to obtain an HBA intermediate rather than an amide compound, and at the same time, in order to prevent the reaction viscosity from increasing and the reaction conversion rate from decreasing due to the formation of salts or impurities, an acid catalyst is used together with the HBM. A heterogeneous solid phase catalyst is used.

At this time, the type and amount of acid catalyst and heterogeneous solid phase catalyst are the same as described in the first step. That is, the acid catalyst may be an inorganic acid, and the inorganic acid is used in an amount of 0.1 to 5 equivalents, preferably 0.5 to 3 equivalents, and the heterogeneous solid catalyst is used in an amount of 1 to 5 equivalents, preferably 1 to 3 equivalents. It is preferable to use more than 3 equivalents of the total solid catalyst. For example, more than 2 equivalents of 35% HCl and more than 2 equivalents of strongly acidic cation exchange resin may be used.

When only inorganic acid is used in the first and second stages without using a heterogeneous solid catalyst, the viscosity of the reactant is very high at 500 to 1500 cps, the first stage reaction conversion rate is 90% or less, and the second stage reaction conversion rate is 85%. It may be around %.

However, when using more than 3 equivalents of the acid catalyst and heterogeneous solid phase catalyst in the first and second steps as in the present invention, there is a risk that stirring will be impaired due to viscosity because the heterogeneous solid catalyst filters out salts, etc. There is no reaction at all, so the reaction occurs evenly throughout, and the reaction conversion rate in each step can be improved to 95%, preferably 98%, and more preferably 99% or more, and highly reactive HBA, not an amide compound, is used as an intermediate product. There are advantages to manufacturing it.

Next, the third step of producing HBM by reacting HBA with methanol under an acid catalyst will be described.

The acid catalyst used in the third step may also be an inorganic acid like that used in the first or second step. That is, the acid catalyst may be one or more inorganic acids selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, and hydrochloric acid, and 0.01 to 1 equivalent of the inorganic acid may be used based on 1 equivalent of HBA.

HBM produced in the third step is weak to heat and prone to hydrolysis in the presence of moisture, but has excellent solvent resistance because it has both lipophilic and hydrophilic groups in the molecule, so it is widely used as a PR thinner in the photoresist process.

The final product prepared through the first to third steps, that is, the HBM mixture, may contain impurities such as a small amount of salt, a large amount of moisture, acid, metal, etc. Remaining impurities, especially acids, can cause corrosion of semiconductor equipment and affect the decomposition or curing speed of photoresist resin, as well as reacting with the alkaline solution used in the developer to cause chip defects. Therefore, there is a need to minimize this.

In particular, the third step is a reversible reaction, and there is a problem in that HBA and water may be generated by the reverse reaction as follows, so it is difficult to use it directly for semiconductor processing.

Therefore, in the present invention, a distillation process is introduced to remove various impurities from HBM produced through the first to third steps. However, because methyl 2-hydroxyisobutyrate and water undergo azeotropic distillation, it is difficult to remove moisture if the distillation process is immediately introduced.

Therefore, it is desirable to first introduce a step to remove salt and moisture prior to the distillation process. The step of removing salt and moisture may include or be an extraction step.

HBM from which salts and moisture have been removed can be extracted using an organic solvent extractant such as dichloromethane, dichloroethane, dichloropropane, and dichlorobutane. For example, after using dichloromethane to obtain an organic layer containing HBM, dichloromethane may be added to the water layer again to extract HBM contained in the water layer. At this time, the extractant can be used in an amount of 30 to 300%, preferably 50 to 100%, based on the weight of the methyl 2-hydroxyisobutyrate mixture.

A trace amount of the acid used during the manufacturing process may remain in methyl 2-hydroxyisobutyrate that has gone through the extraction process, and impurities or acids may be generated through hydrolysis reactions, etc. Therefore, the acid can be removed by passing methyl 2-hydroxyisobutylate through Na ₂ CO ₃ and NaHCO ₃ .

By distilling and purifying the HBM obtained in the extraction process, remaining moisture and low-boiling point and high-boiling point impurities can be additionally removed, and more purified, high-purity HBM can be obtained by using a particle filter or metal filter.

The distillation process may include removing impurities with a boiling point lower than HBM and removing impurities with a boiling point higher than HBM.

For example, the temperature of the primary distillation tower is maintained lower than the boiling point of HBM to remove low-boiling point impurities, and the secondary distillation tower is maintained at a temperature higher than HBM to vaporize HBM and then cool it to recover, and impurities with high boiling point are removed by 2%. It will be possible to remove it from the bottom of the tea distillation tower.

For example, in the distillation process, a tray column or packed column can be used, and the reboiler temperature of the first tower is set to 80 to 140 ℃ under -500 to -600 mmHg, preferably 80 to 100 ℃. The distillation process can be performed while maintaining the temperature at 140~180℃ in the reboiler of the secondary tower.

Meanwhile, methyl 2-hydroxyisobutyrate (HBM) has an ester bond in the compound, so it is easily hydrolyzed by moisture and oxidized by heat, so 2-hydroxy, which is an impurity, is removed during the distillation process. Isobutyric acid (HBA) may be produced.

Therefore, it is desirable to add an antioxidant to prevent hydrolysis and generation of impurities during the distillation process. At this time, as antioxidants, the following primary antioxidants and secondary antioxidants can be added in combination or individually.

Representative examples of the primary antioxidants are phenolic antioxidants, including BHT (Butylated hydroxyanisole), MeHQ (Hydroquinone monomethylether), TBC (4-tert.-Butylcatechol), HQ (Hydroquinone), and Songnox. Products such as 1010, Songnox 1076, Songnox 1135, Songnox 2450, and Songnox 1035 are available.

The secondary antioxidants include phosphite antioxidants such as tris(2,4-di-tert-butylphenyl) phosphite ((2,4-di-tert-butylphenyl) phosphite) and bis(2,4). -di-tert-butylphenyl) pentaerythritol diphosphate) ((bis(2,4-di-tert-butylphenyl pentaerythritol diphosphate)) etc. can be used.

The primary antioxidant and secondary antioxidant can be added in an amount of 10 to 10,000 ppm, preferably 100 to 2,000 ppm, based on the HBM mixture.

By going through the distillation process, it is possible to produce methyl 2-hydroxyisobutyrate that maintains semiconductor-level purity and acid value. However, to further increase purity, the final product can be obtained by passing it through a metal filter or particle filter.

For example, methyl 2-hydroxyisobutyrate that has gone through a distillation process is passed through a metal filter with a pore size of 0.015 um from Entergris and made of PTFE to remove trace amounts of metal. After passing through the metal filter, the methyl 2-hydroxyisobutyrate is filtered through a metal filter with a pore size of 0.1 to 0.1 um from Poll. Higher purity semiconductor grade methyl 2-hydroxyisobutyrate can be produced by passing it through a particle filter made of 0.04 um PTFE or a particle filter made by 3M with a pore size of 0.1~0.04 um and made of Nylon.

Hereinafter, the present invention will be described in more detail through examples. Since these examples are only for illustrating the present invention, the scope of the present invention is not limited by these examples.

<Example 1>

1. HBM manufacturing process

(1) Acetone cyanohydrin production

Add 200 g of sodium cyanide (NaCN, 4.08 equivalent) and 440 g of water to a reactor equipped with a stirrer and stir to dissolve them. Then, while maintaining the reactor temperature below 5°C, slowly add 236.97 g (4.08 equivalent) of acetone and stir for 2 hours. . When stirring is completed, 99.9 g of sulfuric acid is slowly added while maintaining the reactor temperature below 10°C, and the reaction solution is circulated in a vessel containing 3 liters of SCR-BH, a strong acidic cation exchange resin from Samyang Corporation, for 2 hours to react. When the reaction was completed, acetone cyanohydrin could be obtained, and analysis using GC (Gas cromatoghaphy) showed that the conversion rate was over 99.0%.

(2) HBA manufacturing

After slowly adding 85 g of 35% hydrochloric acid to the acetone cyanohydrin where the reaction was completed, the reaction solution was placed in a vessel containing 3 liters of SCR-BH, a strong acidic cation exchange resin from Samyang Corporation, and maintained at 70~80℃ for 3~ By circulating for 5 hours, 2-hydroxy isobutyric acid can be obtained. As a result of analysis using GC, the conversion rate was over 98%.

(3) HBM manufacturing

Methyl 2-hydroxy isobutylate can be obtained by adding 200 g of methanol (MeOH) and 0.5 g of sulfuric acid to the completed 2-hydroxy isobutyric acid and reacting at 70-80°C for 6 hours. As a result of analysis using GC, the conversion rate was over 97%.

2. Extraction step

After the reaction was completed, add 300 g of dichloromethane to the methyl 2-hydroxy isobutyrate, shake sufficiently to separate the layers, obtain the lower layer containing the product (dichloromethane + methyl 2-hydroxy isobutylate), and add 300 g of dichloromethane to the water layer. After adding and shaking sufficiently, methyl 2-hydroxy isobutyrate is extracted from the lower layer. Remaining acids can be additionally removed by passing Na ₂ CO ₃ and NaHCO ₃ through methyl 2-hydroxyisobutyrate that has undergone the extraction process.

3. Distillation step

Methyl 2-hydroxyisobutyrate from which moisture has been removed uses a primary distillation column to remove low-boiling unreacted methanol, dichloromethane as an extractant, and other low-boiling impurities from the top of the tower, and uses a secondary distillation tower to remove high-boiling point impurities. By removing impurities, high purity methyl 2-hydroxyisobutyrate can be obtained. A 50-stage tray column was used as the distillation column, and the reboiler temperature was 80 to 100°C for the first distillation tower, 140 to 180°C for the second distillation tower, and distillation was performed at a vacuum level of -500 to -600 mmHg. 1,000 ppm of BHT, an antioxidant, was added to both the first and second towers and distillation was performed.

4. Metal and particle removal step

The high purity methyl 2-hydroxyisobutyrate previously distilled is passed through a metal filter made by Entergris with a pore size of 0.015um and made of PTFE, and then passed through a particle filter made by Poll with a pore size of 0.04um and made of PTFE to be used as a semiconductor grade. Methyl 2-hydroxyisobutylate of the highest possible purity was obtained.

<Comparative Example 1>

1. HBM manufacturing process

(1) Acetone cyanohydrin production

The method for producing acetone cyanohydrin in Example 1 was the same, except that 239.9 g of sulfuric acid was used instead of using a strongly acidic cation exchange resin. As a result of analysis using GC (Gas cromatoghaphy), the conversion rate was low at 88-90% and the viscosity was 500-800 cps.

(2) HBA manufacturing

The HBA manufacturing process of Example 1 was the same as that of Example 1, except that 500 g of 35% hydrochloric acid was slowly added and the reaction was carried out at 50-60°C for 5-7 hours without using a strong acid cation exchange resin. As a result of analysis using GC, the conversion rate was low at 82-85% and the viscosity was further increased to over 1000 cps.

(3) HBM manufacturing

HBM was prepared in the same manner as Example 1 using the HBA prepared above. As a result of analysis using GC, the conversion rate was low at 78-79%, and a large amount of impurities such as diacetone alcohol and mesityl oxide originating from Acetone were present.

Therefore, it can be seen that the reaction conversion rate when producing HBM through each step of Comparative Example 1 is significantly lower and the viscosity is higher than that of the present invention, making it difficult to apply it to an industrial production process.

Hereinafter, the purity and metal content of HBM manufactured according to the present invention will be examined with reference to the attached drawings.

Figure 1 is a gas chromatogram of HBM prepared according to an example of the present invention, and Table 1 below shows the retention time, area, area %, and label of the peaks shown in Figure 1.

[Table 1]

Looking at Figure 1 and Table 1, four peaks were observed, and the area of the peak that appeared large at a retention time of 8.097 was 99.991. Therefore, it can be seen that the purity of HBM manufactured and purified according to the present invention is 99.991%, which is high enough to be used in semiconductor processes, especially semiconductor processes using EUV light sources.

Figure 2 is a proton NMR chart of HBM prepared according to an embodiment of the present invention.

Looking at Figure 2, peaks were observed at δ _H (ppm) values of 1.275, 3.386, and 3.616, and the areas (integration) of these peaks were 6:1:3, respectively. Therefore, it was confirmed that the product was a peak corresponding to the HBM molecule.

Table 2 below is a table analyzing the amount of metal remaining in HBM manufactured according to an example of the present invention. Metal content was analyzed using ICP-mass.

[Table 2]

Through Table 2 above, it can be confirmed that the product manufactured according to the embodiment of the present invention is methyl 2-hydroxyisobutylate that meets the metal specifications.

The above description is merely an illustrative description of the present invention, and those skilled in the art will be able to make various modifications without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in this specification are not intended to limit the present invention, but rather to explain the present invention, and the scope of protection of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technologies within the equivalent scope should be interpreted as being included in the scope of rights of the present invention.

Claims (15)

Preparing methyl 2-hydroxyisobutyrate according to the following reaction formula;

Removing salt and moisture from the methyl 2-hydroxyisobutyrate; and
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, comprising the step of distilling the methyl 2-hydroxyisobutylate from which salt and moisture have been removed. According to clause 1,
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, characterized in that a heterogeneous solid phase catalyst is used along with an acid catalyst in the step of producing methyl 2-hydroxyisobutylate. According to clause 1,
Method for producing and purifying high purity methyl 2-hydroxyisobutylate for EUV semiconductor process, characterized in that the step of removing the salt and moisture is a step of extracting the methyl 2-hydroxyisobutylate using an extractant. . According to clause 3,
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for EUV semiconductor processing, wherein the extractant is an organic solvent. According to clause 1,
Before the distillation step, high purity methyl 2-hydroxyisobutyrate for the EUV semiconductor process further includes the step of removing acid by passing the methyl 2-hydroxyisobutyrate from which salts and moisture have been removed through Na ₂ CO ₃ or NaHCO ₃ Method for producing and purifying isobutyrate. According to clause 1,
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, further comprising passing the methyl 2-hydroxyisobutyrate obtained through the distillation step through a filter to remove metal or particles. According to clause 1,
The acid catalyst used in the step of producing methyl 2-hydroxyisobutylate is a high-purity methyl 2-hydroxyisobutylate for EUV semiconductor process, characterized in that at least one selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, and hydrochloric acid. Manufacturing and purification method. According to clause 2,
The heterogeneous solid phase catalyst is one or more selected from the group consisting of strongly acidic cation exchange resin, polyvinyl sulfonic acid-grafted polystyrene, silica-sulfuric acid, silica-hypochlorous acid, sulfated zirconium, borated zirconium, and aluminum-polyphosphoric acid. A method for producing and purifying high purity methyl 2-hydroxyisobutyrate for EUV semiconductor processing. According to clause 2,
A method for producing high purity methyl 2-hydroxyisobutyrate, characterized in that the inorganic acid and the heterogeneous solid phase catalyst are used in a total amount of 3 equivalents or more. According to clause 1,
In the step of producing methyl 2-hydroxyisobutyrate, a method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, characterized in that the reaction conversion rate for each reaction step is 90% or more. According to clause 1,
A method for producing and purifying high-purity methyl 2-hydroxyisobutyrate for the EUV semiconductor process, characterized in that an antioxidant is added in the distillation step. According to clause 11,
The antioxidants include BHT (Butylated hydroxyanisole), MeHQ (Hydroquinone monomethylether), TBC (4-tert.-Butylcatechol), HQ (Hydroquinone), Songnox 1010, Songnox 1076, Songnox 1135, Songnox 2450, Songnox 1035, Tris (2, 4-di-tert-butylphenyl) phosphite ((2,4-di-tert-butylphenyl) phosphite), and bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite. ((Method for producing and purifying high purity methyl 2-hydroxyisobutylate for EUV semiconductor process, characterized in that at least one selected from the group consisting of bis(2,4-di-tert-butylphenyl pentaerythritol diphosphate). According to clause 1,
The distillation step includes removing impurities with a boiling point lower than methyl 2-hydroxyisobutylate and removing impurities with a boiling point higher than methyl 2-hydroxyisobutylate. Method for producing and purifying high purity methyl 2-hydroxyisobutyrate. According to clause 1,
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, wherein the methyl 2-hydroxyisobutyrate obtained through the above distillation step is used as a thinner in the photoresist process of the semiconductor process. According to clause 14,
A method for producing and purifying high purity methyl 2-hydroxyisobutylate for the EUV semiconductor process, wherein the semiconductor process includes a process using an EUV light source or an ArF light source.