Low-temperature continuous purification method of diazonaphthoquinone photosensitizer

Abstract

The invention discloses a purification method of an electronic-grade diazo naphthoquinone photosensitizer. The method comprises the following steps: preparing a diazo naphthoquinone photosensitizer solution, adding a corresponding additive into the solution, and carrying out ion exchange to obtain a purified solution. After the purified liquid is subjected to low-temperature distillation, the obtained organic solvent can be used for preparing a photosensitizer solution again, the obtained slurry is washed with ultrapure water, filtered and dried to obtain an electronic-grade product, waste liquid discharge in the purification process is greatly reduced, and the purification effect can reach the electronic-grade standard.

Description

Technical Field

[0001] This invention belongs to the field of electronic chemical purification, specifically relating to a purification method for an electronic-grade diazonoquinone type photosensitizer. Background Technology

[0002] Diazonaphthoquinone-type photosensitizers are a crucial component of G-line / I-line photoresists used in semiconductors, and their properties directly determine key indicators such as photosensitivity and resolution. As photolithography technology continues to advance, the purity requirements for photoresists are constantly increasing, with metal ion content being a critical purity control indicator. Currently, according to the "First Batch of Key New Materials Application Demonstration Guidance Catalogue (2024 Edition)" issued by the Ministry of Industry and Information Technology, the single metal ion content of photoacid generators suitable for I-line / KrF / ArF photoresists must be below 20 ppb, while the metal content of G-line / I-line photosensitive compounds must be below 100 ppb.

[0003] Diazonaphthoquinone-type photosensitizers are mixtures formed by the esterification of 2-diazo-1-naphthoquinone-5-sulfonyl chloride with polyphenolic compounds. Currently, mainstream diazonaphthoquinone-type photosensitizers have up to four phenolic hydroxyl reaction sites, enabling the formation of monosubstituted, disubstituted, and tri / tetrasubstituted products. The highly substituted products have much lower solubility in solvents than the less substituted products. Traditional recrystallization methods alter the proportions of the substituted products in the photosensitizer, resulting in a significantly higher proportion of highly substituted products in the final product, thus changing the product's optical properties. Ion exchange purification, however, is simple to operate and yields higher results, and when performed correctly, it does not affect the proportions of the components in the diazonaphthoquinone-type photosensitizer.

[0004] CN119350200 A proposes a method using nanofiltration membranes and ion exchange resins to purify diazonaquinone-type photoinitiators. However, the crude photosensitizers used in this method have a single metal content of around 100 ppb. Industrial-grade diazonaquinone-type photosensitizers require multi-step chemical synthesis, and the single metal content is generally at the ppm level. Therefore, purifying the ppm-level product to the ppb level is crucial. Furthermore, this method consumes excessive ultrapure water during the conversion of the photosensitizer solution into a solid, generating a large amount of wastewater. Summary of the Invention

[0005] Since diazonoquinone-type photoinitiators are mixtures of different components, the hydroxyl groups in them easily form complexes with metal ions, making it difficult to remove metal impurities from the compound. Furthermore, because photoinitiators are mixtures, the solubility of different components varies. Purification by recrystallization will cause changes in the composition of the product itself, thereby affecting the product performance.

[0006] The purpose of this invention is to overcome the defects of the prior art by providing a purification method for diazonaphthoquinone-type photosensitizers. The method mainly involves three steps: ion exchange, low-temperature distillation, and crystallization, to reduce the single metal content in the photosensitizer to below 50 ppb.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: S1: Dissolve the photosensitizer in an organic solvent to prepare a 20%wt-50%wt solution, add the additive, stir well and set aside for use.

[0008] S2: The sample solution is passed through an ion exchange resin to remove metals, resulting in a purified solution.

[0009] S3: The purified solution is distilled at low temperature to remove most of the solvent. The resulting solvent is then used in S1 to dissolve the sample, and the slurry is collected.

[0010] S4: The slurry from S3 is slowly poured into ultrapure water to crystallize and precipitate. After filtration and drying, electronic-grade diazonoquinone photosensitizer is obtained.

[0011] Furthermore, the organic solvent in S1 is selected from acetone, acetonitrile, 1,4-dioxane, and N,N-dimethylformamide.

[0012] Furthermore, the concentration of the sample in S1 should be determined according to the type of diazonoquinone photosensitizer. If the highest substitution product is a tetrasubstituted product, the concentration should be 20% wt - 30% wt; if the highest substitution product is a trisubstituted product, the concentration should be 30% wt - 40% wt; if the highest substitution product is a disubstituted product, the concentration should be 40% wt - 50% wt.

[0013] Furthermore, the additive mentioned in S1 is one or more of hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, citric acid, oxalic acid, acetic acid, and aminosulfonic acid. Preferably, the additive is hydrochloric acid, nitric acid, sulfuric acid, or hydrofluoric acid, added to make the solution pH 5-6.

[0014] Furthermore, the ion exchange in S2 is a two-stage column chromatography, with the first-stage column packed with a strong acid cation exchange resin and the second-stage column packed with a chelating resin, with a packing ratio of (1~3):1.

[0015] The strong acid cation exchange resin is one of Purolite C150E, Amberlite FPC14H, and LewatitMonoPlus S108H; the chelating resin is one of Amberlite IRC748 and Dowex M4195.

[0016] Further, the resin pretreatment operation in S2 is as follows: the resin is rinsed with pure water, packed into the chromatography column, and rinsed with pure water until the conductivity of the effluent is close to that of pure water. Then, the resin is rinsed with an organic solvent that is the same as that used to dissolve the diazonoquinone photosensitizer until the resin level no longer decreases, thus completing the resin pretreatment.

[0017] Furthermore, the flow velocity through the column in S2 is 2~10 Bv / h, preferably 2~4 Bv / h.

[0018] Furthermore, to prevent the diazonaphthoquinone photosensitizer from precipitating in the resin column, the resin column jacket is filled with coolant to maintain a temperature of approximately 25-30°C.

[0019] Furthermore, since the diazonoquinone group is at risk of decomposition above 70°C, in S3, the solid-liquid separation of the diazonoquinone photosensitizer is carried out under vacuum conditions using a low-temperature distillation device, with the temperature controlled not to exceed 50°C, to prevent the heat-sensitive components from being destroyed.

[0020] Furthermore, the volume of ultrapure water in S4 is 2 to 6 times that of the slurry.

[0021] Furthermore, the diazonoquinone-type photosensitizer comprises any one of the following structural formulas: .

[0022] This invention also provides an electronic-grade diazononaphthoquinone-type photosensitizer. The electronic-grade diazononaphthoquinone-type photosensitizer obtained according to the purification method has metal ion contents of Na, Mg, Al, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Sn of less than 60 ppb, more preferably less than 50 ppb, more preferably less than 40 ppb, more preferably less than 30 ppb, more preferably less than 20 ppb, more preferably less than 10 ppb, more preferably less than 5 ppb, and more preferably less than 1 ppb, respectively. That is, the metal ion contents of Na, Mg, Al, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Sn are less than any one of 60 ppb, 50 ppb, 40 ppb, 30 ppb, 20 ppb, 10 ppb, 5 ppb, and 1 ppb; and the total metal ion content is less than 200 ppb, or less than 100 ppb, or less than 50 ppb.

[0023] The advantages of this invention are: Compared with existing purification technologies, the method of this invention combines ion exchange, low-temperature distillation, and crystallization. By reusing the recovered solvent through distillation, it effectively reduces the use of organic solvents and the generation of wastewater. Furthermore, it can reduce the metal content of the diazonoquinone photosensitizer from the ppm level to the ppb level, demonstrating high efficiency and simple operation. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following.

[0025] The industrial-grade diazonoquinone photosensitizers PAC-1, PAC-2, and PAC-3 contain metal ion impurities including Na, Mg, Al, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Sn, with the content of each metal ion exceeding 20 ppb, or exceeding 50 ppb, or exceeding 100 ppb, or exceeding 200 ppb, or exceeding 500 ppb, or exceeding 1000 ppb; and the total metal content exceeds 10000 ppb.

[0026] Example 1 S1: Dissolve industrial-grade diazonoquinone photosensitizer PAC-1 in 1,4-dioxane to prepare a 50%wt solution, and add a mixed acid of nitric acid and hydrofluoric acid to make the solution pH 5.

[0027] S2: The sample solution was added to the pretreated strong acid cation exchange resin Purolite C150E and chelating resin Amberlite IRC748 by a peristaltic pump at a resin filling ratio of 1:1 and a flow rate of 4 Bv / h.

[0028] S3: Transfer the purified solution from S2 to a distillation flask and perform low-temperature distillation. Stop distilling when solid precipitates.

[0029] S4: Slowly pour the distilled purified solution into twice its volume of ultrapure water to crystallize and precipitate. After filtration and drying, the sample is tested for metal content by ICP-MS.

[0030] Comparative Example 1 The method is the same as in Example 1, except that the strong acid cation exchange resin in S2 is replaced with Lewatit S-100.

[0031] Comparative Example 2 The method is the same as in Example 1, except that the strong acidic cation exchange resin in S2 is replaced with Diaion SA10A.

[0032] Comparative Example 3 The method is the same as in Example 1, except that the chelating resin in S2 is replaced with Diaion CR-10.

[0033] Comparative Example 4 The method is the same as in Example 1, except that the chelating resin in S2 is replaced with Purolite S910.

[0034] Table 1. Metal ion content of the samples to be tested

[0035] As shown in Table 1, the best metal ion removal effect was achieved when using the strong acid cation exchange resin Purolite C150E and the chelating resin Amberlite IRC748 in the mixed bed resin selection.

[0036] Comparative Example 5 The method is the same as in Example 1, except that the chelating resin in S2 is removed and a single resin is used for impurity removal.

[0037] Comparative Example 6 The method is the same as in Example 1, except that the strong acidic cation exchange resin in S2 is removed and a single resin is used for impurity removal.

[0038] Table 2 Metal ion content of the samples to be tested

[0039] As shown in Table 2, using strong acidic cation exchange resin and chelating resin as mixed bed resins results in better metal impurity removal than using a single resin.

[0040] Example 2 S1: Dissolve industrial-grade diazonoquinone photosensitizer PAC-2 in acetonitrile to prepare a 30%wt solution, and add a mixed acid of nitric acid and hydrofluoric acid to make the solution pH 5.

[0041] S2: The sample solution was added to the pretreated strong acid cation exchange resin Purolite C150E and chelating resin Amberlite IRC748 by a peristaltic pump at a resin filling ratio of 1:1 and a flow rate of 4 Bv / h.

[0042] S3: Transfer the purified solution from S2 to a distillation flask and perform low-temperature distillation. Stop distilling when solid precipitates.

[0043] S4: Slowly pour the distilled purified solution into twice its volume of ultrapure water to crystallize and precipitate. After filtration and drying, the sample is tested for metal content by ICP-MS.

[0044] Example 3 The method is the same as in Example 2, except that the flow rate in S2 is reduced to 9 Bv / h.

[0045] Example 4 The method is the same as in Example 2, except that the flow rate in S2 is reduced to 2 Bv / h.

[0046] Example 5 The method is the same as that of Comparative Example 1, except that the resin filling ratio in S2 is changed to 2:1.

[0047] Example 6 The method was the same as in Comparative Example 1, except that the resin filling ratio in S2 was changed to 3:1. The results of the obtained metal ion content are shown in Table 2.

[0048] Table 3 Metal ion content of the samples to be tested

[0049] As shown in Table 3, the metal ion removal effect is best when the resin flow rate is 3 Bv / h and the volume ratio of cation resin to chelating resin is 2:1.

Claims

1. A method for purifying an electronic-grade diazonoquinone-type photosensitizer, characterized in that, The purification method includes the following steps: S1: Prepare sample solution: Dissolve the photosensitizer in an organic solvent to prepare a 20%wt-50%wt solution, add additives, stir well and set aside for use; S2: Ion exchange: The sample solution is passed through an ion exchange resin to remove metals, resulting in a purified solution; S3: The purified solution is distilled at low temperature to remove most of the solvent. The resulting solvent is then used in S1 to dissolve the sample, and the slurry is collected. S4: The slurry from S3 is slowly poured into ultrapure water to crystallize and precipitate. After filtration and drying, electronic-grade diazonoquinone photosensitizer is obtained.

2. The purification method for the electronic-grade diazonoquinone type photosensitizer according to claim 1, characterized in that, The organic solvent mentioned in S1 is selected from acetone, acetonitrile, 1,4-dioxane, and N,N-dimethylformamide.

3. The purification method for the electronic-grade diazonoquinone-type photosensitizer according to claim 1, characterized in that, The concentration of sample in S1 should be determined according to the type of diazonoquinone photosensitizer. If the highest substitution product is a tetrasubstituted product, the concentration should be 20%wt - 30%wt; if the highest substitution product is a trisubstituted product, the concentration should be 30%wt - 40%wt; and for disubstituted and monosubstituted products, the concentration should be 40%wt - 50%wt.

4. The purification method for the electronic-grade diazonoquinone-type photosensitizer according to claim 1, characterized in that, The additives mentioned in S1 are one or more of hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, citric acid, oxalic acid, acetic acid, and aminosulfonic acid, added to a solution with a pH of 5-6.

5. The purification method for the electronic-grade diazonoquinone-type photosensitizer according to claim 1, characterized in that, The ion exchange in S2 is a two-stage column chromatography. The first-stage column is filled with a strong acid cation exchange resin, and the second-stage column is filled with a chelating resin, with a packing ratio of (1~3):

1. The strong acid cation exchange resin is one of Purolite C150E, Amberlite FPC14H, and Lewatit MonoPlus S108H, and the chelating resin is one of Amberlite IRC748 and Dowex M4195.

6. The purification method for the electronic-grade diazonoquinone type photosensitizer according to claim 5, characterized in that, Resin pretreatment in S2: The strong acid cation exchange resin and chelating resin are rinsed with pure water and packed into the chromatography column. The resin is then rinsed with pure water until the conductivity of the effluent is close to that of pure water. The resin is then rinsed with an organic solvent that is the same as that used to dissolve the diazonoquinone photosensitizer until the resin level no longer decreases, thus completing the resin pretreatment.

7. The purification method for the electronic-grade diazonoquinone type photosensitizer according to claim 1, characterized in that, The flow velocity through the column in S2 is 2-10 Bv / h.

8. The purification method for the electronic-grade diazonoquinone type photosensitizer according to claim 1, characterized in that, In S3, under vacuum conditions, a low-temperature distillation apparatus is used to perform secondary purification and solid-liquid separation of the diazonoquinone photosensitizer, with the temperature controlled to not exceed 50°C.

9. The purification method for the electronic-grade diazonoquinone type photosensitizer according to claim 1, characterized in that, The diazonoquinone-type photosensitizer includes any one of the following structural formulas: 。 10. An electronic-grade diazonoquinone-type photosensitizer, characterized in that, The electronic-grade diazonoquinone photosensitizer obtained by the purification method according to any one of claims 1-9 has metal ion contents of Na, Mg, Al, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Sn of less than 60 ppb, more preferably less than 50 ppb, more preferably less than 40 ppb, more preferably less than 30 ppb, more preferably less than 20 ppb, more preferably less than 10 ppb, more preferably less than 5 ppb, and more preferably less than 1 ppb, respectively.

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