Synthesis method of resin monomer hydroquinone monomethacrylate for electron beam photoresist
By using low polarity solvents, polymerization inhibitors and weak acidic ion exchange resins in the synthesis of electron beam photoresist, the problems of low purity and yield of hydroquinone monomethacrylate are solved, and a high-efficiency and low-cost preparation process is achieved.
Patent Information
- Application Number
- CN202411734480.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-04-25
AI Technical Summary
In the prior art, the purity and yield of hydroquinone monomethacrylate are low, resulting in high R&D costs of electron beam photoresist and incomplete industrial chain.
Hydroquinone monomethacrylate was prepared by using low polar saturated alkanes as solvents, and adding polymerization inhibitors and weak acidic ion exchange resins as catalysts.
It improves the purity and yield of the product, reduces the reaction cost, and simplifies process operations, and is suitable for industrial production.
Smart Images
Figure CN119874511A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of photoresists, and in particular relates to a method for synthesizing hydroquinone monomethacrylate, a resin monomer for electron beam photoresists. Background Art
[0002] Photoresist, also known as photoresist, refers to a thin film material that changes its solubility when exposed to ultraviolet light, electron beam, ion beam, X-ray, etc. Photoresist is a pattern transfer medium that uses the different solubility after light reaction to transfer the mask pattern to the substrate. It is currently widely used in the processing and production of fine pattern circuits in the optoelectronic information industry and is a key material in the field of electronic manufacturing.
[0003] Electron beam lithography is widely used to generate submicron or nanostructures, and the choice of substrate depends on the application. Generally, any solid substrate can be used for electron beam lithography, including semiconductors (such as silicon, Ge and GaAs), metals (such as gold, aluminum and titanium), and insulators (such as SiO2, Si3N4). These materials can be either the substrate itself or additional thin films on the substrate.
[0004] Electron beam photoresists are usually divided into positive photoresists and negative photoresists, which can be divided according to whether the cross-linking reaction or the chemical bond breaking reaction is dominant after the photoresist is irradiated. Positive photoresist (positive photoresist): The chemical bond breaking reaction in the photoresist in the exposed area is dominant, and it is easily soluble in the developer. Negative photoresist (negative photoresist): The cross-linking reaction in the photoresist in the exposed area is dominant, and small molecules are cross-linked and polymerized into large molecules, which are difficult to dissolve in the developer.
[0005] At present, my country's electron beam photoresist mainly relies on imports and has not yet achieved mass production. We do not have a self-sufficient industrial system and are particularly prone to being "choked". Synthesizing and improving electron beam photoresist and achieving mass production are urgent and arduous tasks.
[0006] Electron beam photoresist is a photoresist material whose solubility changes under electron beam irradiation. It is mainly used for fine pattern processing in semiconductor manufacturing. It has high technical difficulty and great market value, and is an important category of photoresist.
[0007] Electron beam photoresist has the characteristics of high precision and high resolution in technology, which can meet the strict requirements for fine patterns in semiconductor manufacturing. However, the electron beam photoresist market is highly concentrated worldwide and is mainly monopolized by major international companies such as Japan and the United States. For example, Japanese JSR, Tokyo Ohka, Shin-Etsu Chemical, Sumitomo Chemical, Fujifilm and American DuPont occupy a dominant position.
[0008] In China, although some companies have made certain breakthroughs in the field of electron beam photoresists, high-end products still rely on imports. For example, the T150 A photoresist product launched by Wuhan Taiziwei Company has passed mass production verification, but it still faces challenges in the competition in the high-end market.
[0009] With the rapid development of the semiconductor industry, the market demand for electron beam photoresists continues to grow. The global photoresist market has reached tens of billions of dollars, and the Chinese photoresist market is also growing year by year, and is expected to reach 11.44 billion yuan in 2024. Domestic companies are increasing their R&D investment in the field of high-end photoresists, and some products have been mass-produced or supplied in small batches, but overall efforts are still needed to improve technology levels and market share.
[0010] The hydroquinone monomethacrylate series resin monomer products are an important component of the main resin of electron beam photoresist. The successful research and development of the project can break the technological blockade of developed countries, help my country to systematically carry out research in related fields of electron beam photoresist and realize the localization of photoresist materials, enhance international competitiveness, and safeguard national strategic security. It has strong strategic significance.
[0011] Hydroquinone monomethacrylate series products are widely used in electron beam photoresists due to their good light transmittance and photosensitivity. When hydroquinone monomethacrylate derivatives are polymerized, the double bonds in the propionate benzene monomers are very easy to polymerize, and the acid-sensitive groups in the monomers are also easy to decompose. Therefore, the requirements for purification conditions are very stringent. There are almost no mass-produced products with ultra-clean and high-purity quality requirements in the domestic market. The lack of upstream key raw materials has greatly increased the cost of domestic photoresist research and development. In order to solve the current gap in domestic photoresist technology, the research and development and application of photoresist components are imminent. However, the supply problem of photoresist raw materials has not been solved. There is no complete photoresist industry chain in China. It is very necessary to develop a production process for preparing ultra-clean and high-purity hydroquinone monomethacrylate series products for use in the research and development and application of domestic photoresists. Summary of the invention
[0012] The invention provides a method for synthesizing hydroquinone monomethacrylate, a resin monomer for electron beam photoresist, to solve the technical problems of low purity and low yield of the existing hydroquinone monomethacrylate.
[0013] In view of this, the present invention provides a method for synthesizing hydroquinone monomethacrylate, a resin monomer for electron beam photoresist, comprising the following steps: adding a reaction solvent into a container, adding hydroquinone under stirring, then adding an inhibitor and a catalyst in sequence, adjusting the pH value, cooling, adding isobutyl methacrylate under low temperature conditions, keeping the temperature for reaction, monitoring the reaction progress, sampling and detecting that the reaction is complete, adding water, stirring, extracting and separating phases to obtain an organic phase, drying, concentrating under reduced pressure and evaporating to dryness to obtain hydroquinone monomethacrylate.
[0014] Furthermore, a method for synthesizing hydroquinone monomethacrylate, a resin monomer for electron beam photoresist, comprises the following steps: Add a reaction solvent to a 5L four-necked flask equipped with a stirring paddle, a condenser, and a thermometer, start stirring, add hydroquinone, and then add an inhibitor and a catalyst in sequence, adjust the pH value to 4-5, cool down, add isobutyl methacrylate under low temperature conditions, keep the temperature for reaction for 4-6 hours, monitor the reaction progress, take samples to detect that the reaction is complete, add water, stir, extract and separate the phases to obtain an organic phase, dry it, and then concentrate and evaporate to dryness under reduced pressure to obtain hydroquinone monomethacrylate; Wherein, the inhibitor is p-hydroxyanisole or p-tert-butylcatechol.
[0015] Optionally, the molar ratio of isobutyl methacrylate to hydroquinone is 1:(1-1.2).
[0016] Optionally, the mass ratio of hydroquinone to the reaction solvent is 1:(30-40).
[0017] Optionally, the reaction solvent is a low-polarity alkane solvent.
[0018] Optionally, the low-polarity alkane solvent is cyclohexane, n-hexane or n-heptane.
[0019] Optionally, the addition amount of the polymerization inhibitor is 0.01-0.03% of the mass of isobutyl acrylate.
[0020] Optionally, the catalyst is a weakly acidic ion exchange resin, and specifically a weakly acidic ion exchange resin with a carboxyl group.
[0021] Optionally, the amount of the weakly acidic ion exchange resin added is equal to the mass of isobutyl methacrylate.
[0022] Optionally, the pH value of the weakly acidic ion exchange resin is 4-5.
[0023] Optionally, the low temperature condition is -10-(-20)°C.
[0024] It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages: 1. This application uses isobutyl methacrylate and hydroquinone as reaction raw materials, uses low-polarity saturated alkanes as solvents, adds a small amount of polymerization inhibitor, uses weakly acidic ion exchange resins as catalysts, and adopts extremely dilute solvent reactions to prepare hydroquinone monomethacrylate products. The process route disclosed in the present invention uses low-polarity saturated alkanes as reaction solvents, and the solvent polarity is small, which is conducive to the ester exchange in the positive reaction direction; the reaction raw materials react through ester exchange, using isobutyl methacrylate, and the by-product can be recovered for other uses, and no by-products are generated during the reaction process.
[0025] 2. In the present application, the reaction process uses an extremely dilute reaction environment, which can prevent the polymerization of raw materials and products and improve the conversion rate of the product; adding a small amount of inhibitor during the reaction process can reduce the self-polymerization of the hydroquinone monomethacrylate product and improve the yield. The reaction process uses a weakly acidic ion exchange resin as a catalyst to ensure an acidic environment for the reaction process. After the reaction is completed, the resin recovered by filtration can be regenerated and recycled, thereby ensuring the product conversion rate while reducing the reaction cost.
[0026] 3. The method for synthesizing hydroquinone monomethacrylate resin monomer for electron beam photoresist proposed in this application has a simple reaction process, high efficiency and safety, and is a process route that can be applied to industrial production. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 This is the HPLC spectrum of a standard sample of hydroquinone monomethacrylate resin monomer.
[0028] Figure 2 This is the HPLC spectrum of hydroquinone monomethacrylate resin monomer sample.
[0029] Figure 3 This is the infrared spectrum of hydroquinone monomethacrylate resin monomer sample.
[0030] Figure 4 It is the structural formula of hydroquinone monomethacrylate series products. DETAILED DESCRIPTION
[0031] In order to make the technical scheme of the present invention better understood by the personnel of the technical field, the technical scheme in the embodiment of the present invention is clearly and completely described below. Obviously, the described embodiment is only a part of the embodiment of the present invention, rather than all the embodiments. Based on the embodiment in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or can be prepared by existing methods. Example Example 1
[0032] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 2946 ml of n-hexane was added, stirring was started, 55.1 g of hydroquinone was added, and then 0.0072 g of a polymerization inhibitor p-hydroxyanisole and 71.2 g of a weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -10°C, 71.2 g of isobutyl methacrylate was added, the reaction was kept warm for 4 hours, the reaction progress was monitored, and sampling was performed to detect that the reaction was complete. Then, 800 ml of water was added, stirred, extracted and separated to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.2 g of hydroquinone monomethacrylate with a yield of 93.31%. Example 2
[0033] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 2839 ml of cyclohexane was added, stirring was started, 57.9 g of hydroquinone was added, and then 0.0144 g of a polymerization inhibitor p-hydroxyanisole and 71.2 g of a weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -12°C, 71.2 g of isobutyl methacrylate was added, the reaction was kept warm for 4 hours, the reaction progress was monitored, and after sampling and detection of the reaction was complete, 1000 ml of water was added, stirred, extracted and separated to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.5 g of hydroquinone monomethacrylate with a yield of 93.65%. Example 3
[0034] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 3123 ml of n-heptane was added, stirring was started, 60.6 g of hydroquinone was added, and then 0.021 g of a polymerization inhibitor p-hydroxyanisole and 71.2 g of a weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -14°C, 71.2 g of isobutyl methacrylate was added, and the reaction was kept warm for 5 hours. The reaction progress was monitored, and after sampling and detection, 1000 ml of water was added, stirred, extracted and separated to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.8 g of hydroquinone monomethacrylate with a yield of 93.98%. Example 4
[0035] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 3885ml of n-hexane was added, stirring was started, 63.4g of hydroquinone was added, and then 0.0072g of the inhibitor tert-butylcatechol and 71.2g of weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -16°C, 71.2g of isobutyl methacrylate was added, and the reaction was kept warm for 5h. The reaction progress was monitored and samples were taken for detection. After the reaction was complete, 1000ml of water was added, stirred, extracted and separated to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.2g of hydroquinone monomethacrylate with a yield of 93.25%. Example 5
[0036] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 3123ml of n-heptane was added, stirring was started, 64.5g of hydroquinone was added, and then 0.0144g of the inhibitor tert-butylcatechol and 71.2g of weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -18°C, 71.2g of isobutyl methacrylate was added, the reaction was kept warm for 6h, the reaction progress was monitored, and sampling was performed to detect that the reaction was complete, 1000ml of water was added, the mixture was stirred, and the phases were extracted to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.4g of hydroquinone monomethacrylate with a yield of 93.48%. Example 6
[0037] In a 5L four-necked flask equipped with a stirring paddle, a condenser and a thermometer, 3239ml of cyclohexane was added, stirring was started, 66.2g of hydroquinone was added, and then 0.021g of the polymerization inhibitor tert-butylcatechol and 71.2g of weakly acidic ion exchange resin were added in sequence, the pH value was adjusted to 4.5, the temperature was lowered to -20°C, 71.2g of isobutyl methacrylate was added, the reaction was kept warm for 6h, the reaction progress was monitored, and sampling was performed to detect that the reaction was complete, then 1000ml of water was added, stirred, extracted and separated to obtain an organic phase, which was dried and concentrated under reduced pressure to dryness to obtain 83.6g of hydroquinone monomethacrylate with a yield of 93.70%.
[0038] As can be seen from Examples 1-6, the present application uses isobutyl methacrylate and hydroquinone as reaction raw materials, uses low-polarity saturated alkanes as solvents, adds a small amount of polymerization inhibitor, uses weakly acidic ion exchange resins as catalysts, and adopts extremely dilute solvents to react and prepare hydroquinone monomethacrylate products. The purity of the obtained product is ≥99%, and the total yield of the product obtained by recrystallization is ≥90%. In addition, the process route of the present application is simple and easy to operate, and the product yield of the reaction process is high.
[0039] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for synthesizing hydroquinone monomethacrylate, a resin monomer for electron beam photoresist, characterized in that: The steps include: Add a reaction solvent into a container, add hydroquinone under stirring, then add an inhibitor and a catalyst in sequence, adjust the pH value, cool down, add isobutyl methacrylate under low temperature conditions, keep the temperature for reaction, monitor the progress of the reaction, take samples to detect that the reaction is complete, add water, stir, extract and separate the phases to obtain an organic phase, dry it, concentrate under reduced pressure and evaporate to dryness to obtain hydroquinone monomethacrylate.
2. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The molar ratio of the isobutyl methacrylate to hydroquinone is 1:(1-1.2).
3. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The mass ratio of the hydroquinone to the reaction solvent is 1:(30-40).
4. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The reaction solvent is an alkane solvent with low polarity.
5. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 4, characterized in that: The low polar alkane solvent is cyclohexane, n-hexane or n-heptane.
6. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The addition amount of the polymerization inhibitor is 0.01-0.03% of the mass of isobutyl acrylate.
7. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The catalyst is a weakly acidic ion exchange resin, and specifically a weakly acidic ion exchange resin with a carboxyl group.
8. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 7, characterized in that: The added amount of the weakly acidic ion exchange resin is equal to the mass of isobutyl methacrylate.
9. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 7, characterized in that: The pH value of the weakly acidic ion exchange resin is 4-5.
10. The method for synthesizing hydroquinone monomethacrylate as a resin monomer for electron beam photoresist according to claim 1, characterized in that: The low temperature condition is -10-(-20)℃.