Purification method of high-purity electronic-grade photoacid generator of (4, 7-dihydroxy-1-naphthyl) dimethyl sulfonium trifluoromethanesulfonate

Abstract

The invention provides a purification method of a high-purity electronic-grade photoacid generator derived from (4, 7-dihydroxy-1-naphthyl) dimethyl sulfonium trifluoromethanesulfonate. The problem that photo-acid cannot be purified by traditional recrystallization or directly through an ion exchange column and the like is solved, and the electronic grade standard is achieved. The preparation method comprises the following steps: firstly synthesizing (4, 8-dihydroxy-1-naphthyl) dimethyl sulfonium hydrochloride, then reacting with sodium trifluoromethanesulfonate to generate a crude product (4, 7-dihydroxy-1-naphthyl) dimethyl sulfonium trifluoromethanesulfonate, removing impurities from ethyl acetate, recrystallizing by using methanol and dichloromethane to obtain a pure product, and finally adsorbing by using resin to obtain the high-purity electronic-grade photoacid generator. According to the invention, the stability is high, the metal ion content is low, the purification process is convenient to process, the product is used as a photoresist-level core main material, the product is widely applied in the fields of semiconductor photoresist, other imaging systems, photocureable coatings and the like, the market scale is continuously expanded, and the product is an indispensable key material in semiconductor manufacturing and other related fields.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electronic-grade chemical purification, and particularly relates to a purification method of high-purity electronic-grade photoacid generator (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate. BACKGROUND Photoacid generator is the core component of the chemical amplification photoresist system. When it is irradiated by light of a specific wavelength, it can decompose to generate protons (H + ) or other strong acidic substances. When a specific wavelength of light source is irradiated onto a wafer coated with photoresist, the photoacid generator decomposes under the excitation of light to generate strong acid. The generated acid can catalyze subsequent chemical reactions. Specifically, the photoresist in the exposed area is catalyzed by the acid to promote the crosslinking or solubility change of the photoresist, so that the specific area can be dissolved in the developing solution during the developing process, thereby realizing the transfer of the pattern. As a key component of high-end semiconductor photoresist, photoacid generator has an important influence on the yield, quality, and processing precision of photoresist and photoetching products. Therefore, developing high-performance and high-purity photoacid generator has become an important task in the field of microelectronics technology.

[0002] In addition, the traditional photoacid generator is prone to introduce metal ions and anions during preparation, which cannot meet the high-precision requirements of modern microelectronic manufacturing. In order to improve the purity and stability of the photoacid generator and reduce the purification cost, a new and simple purification method is needed to improve the purity and stability of the photoacid generator, reduce the metal content and halogen content of the compound, and meet the demand of modern microelectronic manufacturing for high-performance photoacid generator. SUMMARY

[0003] The purpose of the present application is to provide a purification method of high-purity electronic-grade photoacid generator (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate. Technical scheme: A purification method of high-purity electronic-grade photoacid generator derived from (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate, comprising the following steps: S1. Adding (4,8-dihydroxy-1-naphthyl) dimethyl sulfonium hydrochloride and sodium trifluoromethylsulfonate into tetrahydrofuran, keeping constant room temperature and stirring for 12 hours, and then distilling under reduced pressure after the reaction is completed to obtain crude (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate; S2. Adding the (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate prepared in S1 into ethyl acetate, ultrasonically beating and filtering and drying to obtain pure (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate; S3. The (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate prepared in S2 is dried and dissolved in methanol, a large amount of dichloromethane is added, stirred at room temperature until a large amount of solid precipitates, washed and dried after filtration to obtain (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate; S4. The (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate is dissolved in solvent acetonitrile, DS-21 resin is added and stirred, then filtered and dried to obtain high-purity (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate. The structure of the high-purity electronic-grade photoacid generator of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate is as follows: .

[0004] As preferred, the molar ratio of (4,8-dihydroxy-1-naphthyl)dimethylsulfonium hydrochloride, sodium trifluoromethylsulfonate and tetrahydrofuran in step S1 is 1:1.1~1.2:15~25, and the reaction temperature is 24~28℃.

[0005] As preferred, the molar ratio of solvent and crude (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate in step S2 is 10~20:1~1.5, and the reaction temperature is 24~28℃. As preferred, the molar ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate, methanol and dichloromethane in step S3 is 1:0.1~0.2:30~40, and the reaction temperature is 24~28℃.

[0006] As preferred, the molar ratio of 2-adamantane acid-sodium trifluoropropyl sulfonate and M-salt chloride in step S3 is 1:0.6~0.8. As preferred, the volume ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate and resin in step S4 is 3~4:1.

[0007] The resin in step S4 includes any one of DS-21, LK-4, Amberlite IRC748, Purolite-UCW1080, 6150.

[0008] Another aspect of the present application provides (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate purified by the method, wherein the content of each metal ion in the (4,7-dihydroxy-1-naphthyl)dimethylsulfonium triflate is less than 100 ppb, further preferably less than 50 ppb, further preferably less than 20 ppb, further preferably less than 10 ppb.

[0009] The metal ions include any one or a combination of Ag, Al, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Zn, Cd, Ba, Co, Li, Sr, B, Bi, Ga, In, Tl, Hg, As, Sb, Be, Ti, Mo.

[0010] Beneficial effects: Compared with the prior art, the present application has the following characteristics: the present application provides a high-purity electronic-grade photoacid generator of (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate, the compound has good stability, the purification method is simple, the purity is high, halogen ions are not introduced, the metal ion content is low, and the prepared product is used as a core main material of DUV photoresist grade, and has wide application in the fields of semiconductor photoresist, other imaging systems, photocuring coatings and the like. As a key raw material of semiconductor photoresist, the photoacid generator has high industrial value and is widely used in a series of liquid crystal display materials with special functions, semiconductor photoresist materials, holographic photosensitive materials, membrane separation materials, intelligent plastics, contact lenses and drug carriers, and therefore has high requirements on the difficulty of synthesis process, purity, metal ion content and the like.

[0011] At present, the preparation of (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate cannot control the content of metal ions in the synthesis stage, thereby greatly affecting the product color, metal ion and anion content, and the process amplification is relatively difficult. The present application provides a purification method of (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate high-purity electronic-grade photoacid generator. The method improves the purity and stability of the photoacid generator through recrystallization, resin adsorption and the like, reduces the metal content and halogen content of the compound, and meets the demand of modern microelectronic manufacturing on high-performance photoacid generators. Compared with the prior art, the present application has the following advantages and positive effects: the present application provides a purification method of (4,7-dihydroxy-1-naphthyl) dimethyl sulfonium triflate photoacid generator, which can be used as a key raw material of photoresist in the field of high-end liquid crystal and chip manufacturing. The product of the present application has low water content and impurity content, low halogen ion and metal ion content, high product yield, low manufacturing cost, and can realize large-scale production and application.

[0012] The overall process technical route of the present application is simple to operate, convenient to post-treat, environment-friendly, and conducive to realizing green production. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1The HPLC spectrum of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate as a photoacid-generating agent.

[0014] Figure 2 It is a photoacid-generating agent of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate. 1 H NMR spectrum.

[0015] Figure 3 It is a photoacid-generating agent of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate. 13 C10 NMR spectrum. Detailed Implementation

[0016] The resin purification method for the sulfonate photoacid generator of this application will be further described in detail below with reference to specific embodiments. Example 1 S1. Add (4,8-dihydroxy-1-naphthyl)dimethylsulfonium hydrochloride and sodium trifluoromethanesulfonate to tetrahydrofuran, maintain a constant room temperature and stir for 12 hours. After the reaction is completed, distill under reduced pressure to obtain crude (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate. In step S1, the molar ratio of (4,8-dihydroxy-1-naphthyl)dimethylsulfonium hydrochloride, sodium trifluoromethanesulfonate and tetrahydrofuran is 1:1.1:20, and the reaction temperature is 24 ~ 28 ℃.

[0017] S2. The (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate prepared in S1 was added to ethyl acetate, stirred, sonicated, filtered, and dried to obtain pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate; in step S2, the molar ratio of solvent to crude (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate was 10:1.5, and the reaction temperature was 24~28 ℃. S3. The pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate prepared in S2 is dried and dissolved in methanol. A large amount of dichloromethane is added, and the mixture is stirred at room temperature until a large amount of solid precipitates. After filtration, washing, and drying, pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate is obtained. In step S3, the molar ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate to methanol and dichloromethane is 1:0.2:30, and the reaction temperature is 24~28 ℃.

[0018] S4. Dissolve pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate in acetonitrile, add DS-21 resin and stir, then filter, distill under reduced pressure and dry to obtain high-purity (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate; the volume ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate to resin in step S4 is 3~4:1.

[0019] Example 2 The steps are the same as in Example 1, except that the resin in step S4 is LK-4 resin.

[0020] Example 3 The steps are the same as in Example 1, except that the resin in step S4 is Amberlite IRC748 resin.

[0021] Example 4 The steps are the same as in Example 1, except that the resin in step S4 is Purolite-UCW1080 resin.

[0022] Example 5 The steps are the same as in Example 1, except that the resin in step S4 is 6150 resin.

[0023] Example 6 The steps are the same as in Example 1, except that in step S4 the resin is a mixture of Amberlite IRC748 and DS-21 resins, with a mass ratio of 1:1.

[0024] The (4,7-dihydroxy-1-naphthyl)dimethylsulfonate prepared by the method described in the above embodiments was analyzed by ICP-MS, and the results are shown in the table below:

Claims

1. A method for purifying a high-purity electronic-grade photoacid generator derived from (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate, characterized in that: Includes the following steps: S1. Add (4,8-dihydroxy-1-naphthyl)dimethylsulfonium hydrochloride and sodium trifluoromethanesulfonate to tetrahydrofuran, stir and react at room temperature, and distill under reduced pressure after the reaction is completed to obtain crude (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate; S2. The crude (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate prepared in S1 was added to ethyl acetate, stirred, sonicated, filtered and dried to obtain pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate; S3. The pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonate prepared in S2 was dried and dissolved in methanol. Dichloromethane was added, and the solid precipitated under stirring at room temperature. The solid was filtered, washed, and dried to obtain pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonate. S4. Dissolve pure (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate in acetonitrile, add resin and stir, then filter, distill under reduced pressure and dry to obtain high-purity (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate.

2. The purification method according to claim 1, characterized in that: In step S1, the molar ratio of (4,8-dihydroxy-1-naphthyl)dimethylsulfonium hydrochloride, sodium trifluoromethanesulfonate, and tetrahydrofuran is 1:1.1 ~ 1.2:15 ~ 25.

3. The purification method according to claim 2, characterized in that: The reaction temperature in step S1 is 24 ~ 28 ℃.

4. The purification method according to claim 1, characterized in that: In step S2, the molar ratio of the solvent to the crude product (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate is 10 ~ 20: 1 ~ 1.

5.

5. The purification method according to claim 4, characterized in that: The reaction temperature in step S1 is 24 ~ 28 ℃.

6. The purification method according to claim 1, characterized in that: In step S3, the molar ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate to methanol and dichloromethane is 1:0.1 ~ 0.2:30 ~ 40.

7. The purification method according to claim 6, characterized in that: The reaction temperature in step S3 is 24 ~ 28 ℃.

8. The purification method according to claim 1, characterized in that: The resin in step S4 includes any one of DS-21, LK-4, Amberlite IRC748, Purolite-UCW1080, and 6150.

9. The purification method according to claim 8, characterized in that: The volume ratio of (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate to resin is 1:3~4.

10. The (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate obtained by the method according to any one of claims 1-9, wherein the content of each metal ion in the (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate is less than 100 ppb, more preferably less than 50 ppb, more preferably less than 20 ppb, and more preferably less than 10 ppb; The metal ions include any one or more combinations of Ag, Al, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Zn, Cd, Ba, Co, Li, Sr, B, Bi, Ga, In, Tl, Hg, As, Sb, Be, Ti, and Mo.

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