Preparation method for regulating and controlling monomer composition in ArF photoresist resin molecular chain
By controlling the monomer composition in the ArF photoresist resin molecular chain, the problem of inconsistent monomer composition in traditional methods was solved, and a narrowly distributed resin was synthesized, which improved the photosensitivity and pattern edge quality of the photoresist.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-19
- Publication Date
- 2026-03-31
AI Technical Summary
When photoresist resins are prepared using traditional methods, the monomer composition in each molecular chain is inconsistent, leading to differences in reaction rate and dissolution rate, which affects the edge roughness of the photolithographic pattern.
By controlling the monomer composition in the ArF photoresist resin molecular chain, a partial monomer was used as the reaction substrate. The dropping acceleration rate was adjusted according to the monomer reaction rate to ensure that the monomer composition in the resin molecular chain was consistent. The initiator and monomer were dropped separately to achieve the target molar ratio, and a narrowly distributed resin was synthesized.
This method achieves uniformity in monomer composition within the photoresist resin molecular chain, improves the photosensitivity of the photoresist, reduces the edge roughness of the photolithographic pattern, and enhances the performance of the photoresist.
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Figure CN121758671A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of semiconductor materials, and particularly relates to a preparation method for controlling the monomer composition in the molecular chain of ArF photoresist resin. Background Technology
[0002] Photoresist, as a photosensitive material, is a key processing material in the fine fabrication technology of integrated circuits. Among them, methacrylic resin, as a component of photoresist, determines the performance of photoresist and is currently a hot topic in photoresist material research.
[0003] The photosensitivity, etching resistance, adhesion, and solubility of photoresists mainly depend on the types and proportions of various functional groups in the photoresist resin molecular chain. The traditional method involves free radical polymerization of methacrylate monomers with different functional groups and an initiator to form a composite material. This polymerization method typically uses a pure solvent or a mixture of initiator and solvent as the reaction substrate, with all monomers mixed and added dropwise simultaneously. However, due to differences in the polymerization reactivity and reaction rate of monomers with different functional groups, the traditional method uses an excess of some monomers to reduce the differences in monomer composition in different molecular chains of the resin, ultimately resulting in a low overall monomer conversion rate. When photoresist resins are prepared using traditional methods, the proportions of each monomer in different molecular chains are not entirely the same, leading to varying degrees of polymerization. This affects the reaction rate and dissolution rate of the photoresist in the subsequent photoreaction, resulting in poor edge roughness of the photolithographic pattern. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing ArF photoresist resin with monomer composition controlled in the molecular chain. The aim is to improve the inconsistent proportion of monomers with different functional groups in each molecular chain of the polymer in traditional polymerization methods, reduce the differences in reaction and dissolution rates of each molecular chain, synthesize a resin with narrow distribution and uniform composition, improve the photosensitivity of the photoresist, and reduce the edge roughness of the photolithographic pattern.
[0005] This invention is achieved by a method for preparing a monomer composition in the molecular chain of ArF photoresist resin, comprising the following steps: S1) Determine the types and proportions of monomers in the target resin molecular chain: The monomer types are any two or three of the following: monomers containing polar groups, monomers containing acid deprotected groups, and monomers containing lactone groups. The molar ratio of each monomer in the target resin molecular chain is monomers containing polar groups: monomers containing acid deprotected groups: monomers containing lactone groups = a0: b0: c0. S2) Divide the weight of each monomer into two parts. The first part is used as the base liquid, and the second part is added to the reaction system dropwise. The first part accounts for 10%-20% of the total weight of each monomer. The first portion of the weight of each monomer is thoroughly mixed with the first solvent to form the reaction base liquid. Based on the different reaction rates of each monomer, the molar ratio of each monomer in the target resin molecular chain is taken as a0:b0:c0 (monomers with polar groups: monomers with acid-deprotected groups: monomers with lactone groups). The proportion of monomers with slower reaction rates is increased, and the proportion of monomers with faster reaction rates is decreased. The molar ratio of each monomer in the reaction base liquid is a1:b1:c1. This ensures that in the initial stage of the dropwise reaction, the resin molecules polymerized in the reaction base liquid have the target monomer composition a0:b0:c0, and maintain relative equilibrium with the unreacted monomers. The molar ratio of the unreacted monomers is a2:b2:c2 (monomers with polar groups: monomers with acid-deprotected groups: monomers with lactone groups). Heat the reaction substrate to the initiator decomposition temperature; The second portion of the weight of each monomer and the initiator are added dropwise to the reaction substrate at a constant rate, one by one. The second portion of the weight of each monomer accounts for 80%-90% of the total weight of the monomer. The molar ratio of each monomer is the same as the molar ratio of the monomers in the target resin molecular chain, i.e., monomers containing polar groups: monomers containing acid-deprotected groups: monomers containing lactone groups = a0: b0: c0. The dropwise addition time of each monomer is directly proportional to the reaction rate of each monomer. The monomer composition of the resin generated in the reaction substrate is always maintained at a ratio of monomers containing polar groups: monomers containing acid-deprotected groups: monomers containing lactone groups = a0: b0: c0, and the molar ratio of unreacted monomers is a2: b2: c2, and this is kept in dynamic equilibrium. The reaction is terminated immediately after all monomers and initiators have been added. S3: Cooling reaction liquid; S4: The unreacted monomers and polymerized resin in the reaction solution are precipitated by a second solvent and then separated by solid-liquid separation. The precipitate is then vacuum dried to obtain the photoresist resin.
[0006] Furthermore, the monomer containing the polar group is any one or a mixture of several of the following structures:
[0007] Among them: R9, R 12 R 14 For H or CH3, R 10 R 11 C w H 2w w is an integer between 0 and 4, R 13 C x H 2x x is an integer from 1 to 4, R15 C y H 2y+1 y is an integer between 0 and 4.
[0008] Furthermore, the acid-deprotected monomer is any one or a mixture of the following structures:
[0009] Where: R1, R3, R5, and R7 are H or CH3, R2, R4, and R... 6、 R8 is C v H 2v+1 v is an integer between 0 and 4.
[0010] Furthermore, the monomer containing the lactone group is any one or a mixture of the following structures:
[0011] Where: R 16 R 18 R 20 For H or CH3, R 17 R 19 R 21 C z H 2z z is an integer from 1 to 4.
[0012] Furthermore, the weight of the first part accounts for 12%-20% of the total weight of each monomer; preferably, the weight of the first part accounts for 15%-18% of the total weight of each monomer.
[0013] Furthermore, the first solvent is one or a mixture of several of propylene glycol methyl ether acetate, tetrahydrofuran, 2-butanone, propylene glycol methyl ether, and dichloromethane.
[0014] Furthermore, the total weight of each monomer is 20%-40% of the weight of the first solvent, preferably 20%-30%, and most preferably 25%.
[0015] Furthermore, the first portion of the weight of each monomer is thoroughly mixed with the first solvent to form a reaction base liquid. By weight, the first solvent as the base liquid accounts for 10%-30% of the total weight of the first solvent, preferably 15%-25%.
[0016] Furthermore, the initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovalerate, and dimethyl azobisisobutyrate.
[0017] Furthermore, the initiator decomposition temperature refers to a specific temperature at which the initiator has a half-life of 1 hour in the first solvent; the initiator decomposition temperature is typically 65℃-80℃.
[0018] Furthermore, the second portion of the weight of each monomer is mixed with the first solvent and then added dropwise to the reaction substrate.
[0019] Furthermore, the initiator is mixed with the first solvent and then added dropwise to the reaction substrate.
[0020] Furthermore, the initiator is added over a period of 3-6 hours, preferably 3-4 hours.
[0021] Furthermore, the initiator accounts for 10%-40% of the total weight of all monomers, preferably 12%-20%.
[0022] Furthermore, the second portion of the weight of each monomer and the initiator are added simultaneously to the reaction substrate at a constant rate by adding them separately. The addition time of the monomer containing polar groups, the monomer containing acid deprotection groups, and the monomer containing lactone groups is independently 0.8-1.2 times the addition time of the initiator. For example, taking an initiator addition time of 4 hours as a baseline, the addition time of each monomer is 0.8-1.2 times the initiator addition time. The reaction rates of each monomer from fastest to slowest are: monomers containing lactone groups > monomers containing polar groups > monomers containing acid deprotecting groups. Then, the addition times of each monomer from longest to shortest are: monomers containing lactone groups > monomers containing polar groups > monomers containing acid deprotecting groups. Specifically, the addition time ratio of polar group monomers: monomers containing acid deprotecting groups: monomers containing lactone groups: initiator is 4h:3.2h:4.8h:4h.
[0023] Furthermore, the second solvent is one or a mixture of several of methanol, n-hexane, isopropanol, and n-pentane.
[0024] The present invention also provides a photoresist resin, which is obtained by the above preparation method.
[0025] The present invention also provides an ArF photoresist, which is prepared from the above-mentioned photoresist resin.
[0026] The photoresist resin of the present invention is prepared into a photoresist according to the following formula: Photoresist can be prepared by mixing photoresist resin, photosensitizer, propylene glycol methyl ether acetate and propylene glycol methyl ether in a certain proportion.
[0027] Photolithography process conditions for photoresist: baking at 110℃ for 2 minutes, exposure energy of 20 mJ / cm² 2 The development time is 60 seconds to obtain the photolithographic pattern.
[0028] The photoresist resin prepared by this invention was formulated into a photoresist, and then a photolithographic pattern was obtained through baking, exposure, development and drying processes. The results showed that the photoresist pattern had more uniform properties and less edge roughness.
[0029] The beneficial effects achieved by this invention are as follows: Traditional ArF photoresist resin synthesis methods use pure solvent or a mixture of initiator and solvent as the reaction substrate, with all monomers mixed and added dropwise simultaneously. However, due to differences in the polymerization rates and reaction rates of monomers with different functional groups, traditional methods often involve adding an excess of some monomers to reduce the differences in monomer composition across different molecular chains of the resin, ultimately resulting in a low overall monomer conversion rate. The photoresist resin prepared by traditional methods exhibits inconsistent monomer proportions across different molecular chains, leading to a wider molecular distribution. This affects the reaction and dissolution rates of the photoresist during subsequent photoreactions, resulting in poor edge roughness of the lithographic pattern.
[0030] Compared to traditional methods, this application utilizes a subset of monomers as the reaction substrate and adjusts the dropping rate according to the reaction rate of monomers with different functional groups. This results in a consistent monomer composition ratio within the final synthesized photoresist resin molecular chain, allowing for controllable and narrowly distributed monomer composition. The resulting photoresist exhibits high photosensitivity and low edge roughness. Attached Figure Description
[0031] Figure 1 This refers to the monomer ratio of the resin generated during the reaction process in Example 1.
[0032] Figure 2 This refers to the monomer ratio of the resin generated during the reaction process in Comparative Example 1.
[0033] Figure 3 This refers to the monomer ratio of the resin generated during the reaction process in Example 2.
[0034] Figure 4 This refers to the monomer ratio of the resin generated during the reaction process in Comparative Example 2.
[0035] Figure 5 This refers to the monomer ratio of the resin generated during the reaction process in Example 3.
[0036] Figure 6 This refers to the monomer ratio of the resin generated during the reaction process in Comparative Example 3.
[0037] Figure 7 This is the photolithographic pattern of Example 1.
[0038] Figure 8 The photolithographic pattern is from Comparative Example 1.
[0039] Figure 9 This is the photolithographic pattern of Example 2.
[0040] Figure 10 The photolithographic pattern is from Comparative Example 2.
[0041] Figure 11 This is the photolithographic pattern of Example 3.
[0042] Figure 12 This is the photolithographic pattern of Comparative Example 3. Detailed Implementation
[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0044] Example 1
[0045] Determine the types and proportions of monomers in the target resin molecular chain: The monomer types are as shown above, namely monomer m1 containing polar groups, monomer m2 containing acid deprotecting groups, and monomer m3 containing lactone groups. The molar ratio of monomers in the target resin molecular chain is m1:m2:m3 = 20:40:40. The reaction rates of monomers containing polar groups (m1), monomers containing acid-deprotected groups (m2), and monomers containing lactone groups (m3) are arranged from fastest to slowest as follows: m3 > m1 > m2. The total weight of the above monomers is 25 wt% of the weight of the first solvent propylene glycol methyl ether acetate. A portion of the monomers are mixed thoroughly with propylene glycol methyl ether acetate, which accounts for 20% of the total solvent weight, at a molar ratio of m1:m2:m3=18:48:34, and the weight of the monomers accounts for 18 wt% of the total monomer weight. This mixture is then used as the reaction base liquid. The reaction substrate was heated to the initiator decomposition temperature of 66°C. Azobisisoheptanenitrile was used as the initiator. The remaining monomers were mixed thoroughly with propylene glycol methyl ether acetate at the same molar ratio as the target (m1:m2:m3 = 20:40:40), with the monomers accounting for 82 wt% of the total weight. The initiator, azobisisobutyronitrile, was mixed thoroughly with propylene glycol methyl ether acetate at 12 wt% of the total monomer weight. When the reaction solution was heated to 66°C, the remaining monomers and the initiator were added dropwise simultaneously. The initiator was added over 4 hours, and the addition time of other monomers was based on the initiator addition time, with the ratio of the initiator addition time to the initiator addition time being m1:m2:m3:initiator = 4h:3.2h:4.4h:4h. Samples were taken every 30 minutes from 0-1 hour of addition to analyze the proportion of monomers in the reaction solution. Samples were taken every hour from 1-4 hours to analyze the proportion of monomers in the reaction solution. After the reaction was completed, i.e., after all monomers and initiators had been added, samples were taken to analyze the proportion of monomers in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0046] Comparative Example 1 The reaction substrate was prepared using pure solvent propylene glycol methyl ether acetate (which accounted for 20 wt% of the total solvent weight), and heated to the initiator decomposition temperature of 66°C. The initiator was azobisisoheptanenitrile. To achieve the target resin monomer molar ratio of m1:m2:m3=20:40:40, considering the polymerization reactivity of different monomers, all monomers were thoroughly mixed with all initiators and propylene glycol methyl ether acetate (which accounted for 80 wt% of the total solvent weight) at a molar ratio of m1:m2:m3=19:46:35 and set aside. The initiator weight was 12 wt% of the total monomer weight. Dropping was started after the reaction solution was heated to 66°C and the dropping time was 4 hours. Samples were taken every 30 minutes from 0 to 1 hour to analyze the proportion of synthetic resin monomers in the reaction solution. Samples were taken every hour from 1 to 4 hours to analyze the proportion of synthetic resin monomers in the reaction solution. After the reaction was completed, i.e. after all monomers and initiators had been added, samples were taken to analyze the proportion of monomers in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0047] Example 2
[0048] Determine the types and proportions of monomers in the target resin molecular chain: The monomer types are as shown above, namely monomer m4 containing polar groups, monomer m5 containing acid deprotecting groups, and monomer m6 containing lactone groups. The molar ratio of monomers in the target resin molecular chain is m4:m5:m6 = 20:45:35. The reaction rates of monomers containing polar groups (m4), monomers containing acid-deprotected groups (m5), and monomers containing lactone groups (m6) are arranged from fastest to slowest as follows: m6 > m4 > m5. The total weight of the above monomers is 25 wt% of the weight of the first solvent, propylene glycol methyl ether acetate. A portion of the monomers, with a molar ratio of m4:m5:m6=18:52:30, accounting for 16 wt% of the total monomer weight, is thoroughly mixed with propylene glycol methyl ether acetate, which accounts for 20% of the total solvent weight, and used as the reaction base liquid. The reaction substrate was heated to the initiator decomposition temperature of 66°C. Azobisisoheptanenitrile was used as the initiator. The remaining monomers were mixed thoroughly with propylene glycol methyl ether acetate at the same molar ratio as the target (m4:m5:m6 = 20:45:35), accounting for 84 wt% of the total monomer weight. The initiator, azobisisobutyronitrile (AIBN), was also mixed thoroughly with propylene glycol methyl ether acetate at 15 wt% of the total monomer weight. When the reaction mixture was heated to 66°C, the remaining monomers and the initiator were added dropwise simultaneously. The initiator was added over 4 hours, and the addition times for other monomers were based on the initiator addition time, with a ratio of m4:m5:m6:initiator = 4h:3.6h:4.2h:4h. Samples were taken every 30 minutes from 0-1 hour of addition to analyze the monomer ratio in the reaction mixture. Samples were taken every hour from 1-4 hours to analyze the monomer ratio in the reaction mixture. After the reaction was completed, i.e., after all monomers and initiator had been added, samples were taken to analyze the monomer ratio in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0049] Comparative Example 2 The reaction substrate was prepared using pure solvent propylene glycol methyl ether acetate (which accounted for 20 wt% of the total solvent weight), and heated to the initiator decomposition temperature of 66°C. The initiator was azobisisoheptanenitrile. To achieve the target resin monomer molar ratio of m4:m5:m6=20:45:35, considering the polymerization reactivity of different monomers, all monomers were thoroughly mixed with all initiators and propylene glycol methyl ether acetate (which accounted for 80 wt% of the total solvent weight) at a molar ratio of m4:m5:m6=21:50:29 and set aside. The initiator, azobisisobutyronitrile, accounted for 15 wt% of the total monomer weight. Dropping was started after the reaction solution was heated to 66℃ and the dropping time was 4 hours. From 0 to 1.0 hours of dropping, samples were taken every 30 minutes to analyze the proportion of synthetic resin monomers in the reaction solution. From 1 to 4 hours, samples were taken every hour to analyze the proportion of synthetic resin monomers in the reaction solution. After the reaction was completed, i.e. after all monomers and initiators had been added, samples were taken to analyze the proportion of monomers in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0050] Example 3
[0051] Determine the types and proportions of monomers in the target resin molecular chain: The monomer types are as shown above, namely monomer m7 containing acid deprotected groups and monomer m8 containing lactone groups. The molar ratio of monomers in the target resin molecular chain is m7:m8 = 50:50. The reaction rates of the acid-deprotected monomer m7 and the lactone-containing monomer m8, arranged from fastest to slowest, are m7>m8; The total weight of the monomers is 25 wt% of the weight of the first solvent 2-butanone. A portion of the monomers, with a molar ratio of m7:m8 = 41:59, accounting for 20 wt% of the total monomer weight, is thoroughly mixed with 2-butanone, which accounts for 20% of the total solvent weight, and used as the reaction base liquid. The reaction substrate was heated to the initiator decomposition temperature of 80°C. Azobisisobutyronitrile (AIBN) was used as the initiator. The remaining monomers were mixed thoroughly with 2-butanone at the target molar ratio of m7:m8 = 50:50, with each monomer accounting for 80 wt% of the total weight. The initiator, azobisisobutyronitrile (AIBN), was mixed thoroughly with 2-butanone at 20% of the total monomer weight. When the reaction solution was heated to 80°C, the remaining monomers and the initiator were added dropwise simultaneously. The initiator was added over 4 hours, and the addition time for the other monomers was based on the initiator addition time, with a ratio of m7:m8:initiator = 4h:3.4h:4h. Samples were taken every 30 minutes from 0 to 1 hour of addition to analyze the proportion of monomers in the reaction solution. Samples were taken every hour from 1 to 4 hours to analyze the proportion of monomers in the reaction solution. After the reaction was completed, i.e., after all monomers and initiator had been added, samples were taken to analyze the proportion of monomers in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0052] Comparative Example 3 The reaction substrate uses pure solvent 2-butanone (which accounts for 20 wt% of the total solvent weight), and is heated to the initiator decomposition temperature of 80°C. The initiator used is azobisisobutyronitrile. To achieve the target resin monomer molar ratio of m7:m8=50:50, considering the polymerization reactivity of different monomers, all monomers were thoroughly mixed with all initiators and 2-butanone (which accounted for 80 wt% of the total solvent weight) at a molar ratio of m7:m8=46:54 and set aside. The initiator weight was 20 wt% of the total monomer weight. The initiator was added dropwise after the reaction solution was heated to 80°C for 4 hours. During the first 0-1 hour of addition, samples were taken every 30 minutes to analyze the proportion of synthetic resin monomers in the reaction solution. During the first 1-4 hours, samples were taken every hour to analyze the proportion of synthetic resin monomers in the reaction solution. After the reaction was completed, i.e. after all monomers and initiators had been added, samples were taken to analyze the proportion of monomers in the synthetic resin. After the reaction is complete, cool the reaction solution to room temperature; The reaction solution was poured into methanol for precipitation, filtration, washing, and vacuum drying to obtain photoresist resin.
[0053] The photoresist resins obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were formulated into photoresist according to the following formula. The photoresist was then subjected to baking, exposure, development, and drying processes to obtain photolithographic patterns: The photoresist is prepared by mixing the photoresist resin, the photosensitizer TPS-PFBS, and a mixed solvent consisting of propylene glycol methyl ether acetate and propylene glycol methyl ether in a mass ratio of 60:40, with the above substances mixed evenly in a mass ratio of 1:0.03:9. Photolithography process conditions for photoresist: film thickness 2500 Å, PAB 115℃ 90s, PEB 105℃ 90s, exposure energy 30 mJ / cm² 2 The photolithographic pattern is obtained. The process sampling and product photolithography results of Examples 1 to 3 and Comparative Examples 1 to 3 were tested respectively, and the test results are as follows: Table 1. Product composition and photolithography results of Example 1 and Comparative Example 1
[0054] Table 2. Product composition and photolithography results of Example 2 and Comparative Example 2
[0055] Table 3. Product composition and photolithography results of Example 3 and Comparative Example 3
[0056] The physicochemical and photolithographic data of the resins synthesized using the preparation methods of Example 1 and Comparative Example 1 are shown in Table 1. Figure 1 , Figure 2 , Figure 7 and Figure 8As shown, when the proportions of the target resins are similar, i.e., the proportions of the resin carbon spectrum components are similar, the preparation method of this application can synthesize resins with narrow distributions and uniform monomer composition. In addition, from... Figure 7 and Figure 8 The comparison shows that when the resin prepared by the method of this application is configured into a photoresist, the overall sensitivity of the photoresist decreases, so the target pattern can be achieved with lower energy, the line edges become smoother and straighter, and it has low edge roughness.
[0057] The physicochemical and photolithographic data of the resins synthesized using the preparation methods of Example 2 and Comparative Example 2 are shown in Table 2. Figure 3 , Figure 4 , Figure 9 and Figure 10 As shown, when the proportions of the target resins are similar, i.e., the proportions of the resin carbon spectrum components are similar, the preparation method of this application can synthesize resins with narrow distributions and uniform monomer composition. In addition, from... Figure 9 and Figure 10 The comparison shows that the resin prepared by the method of this application can improve the photosensitivity and reduce the edge roughness of the photoresist after it is formulated into a photoresist, thereby improving photolithography defects.
[0058] The physicochemical and photolithographic data of the resins synthesized using the preparation methods of Example 3 and Comparative Example 3 are shown in Table 3. Figure 5 , Figure 6 , Figure 11 and Figure 12 When the target resin proportions are similar, i.e., the resin carbon spectrum composition proportions are similar, the preparation method of this application can synthesize resins with narrow distributions and uniform monomer composition. Furthermore, from... Figure 11 and Figure 12 The comparison shows that the resin prepared by the method of this application, after being configured into a photoresist, has improved photosensitivity, smoothed the edges of the pattern, and improved the roundness of the pattern. This invention, based on the differences in polymerization rates and reaction rates of monomers containing different functional groups, uses a portion of the monomers as the reaction substrate, while the remaining monomers and initiators are added dropwise at different rates to synthesize the resin. This ensures that the monomer proportions in different molecular chains are essentially consistent, resulting in a uniform and narrowly distributed overall resin composition. This improves the uniformity of the photoresist resin molecules, enhances the resin's photosensitivity, reduces the edge roughness of the photoresist, improves photoresist performance, and ultimately increases product yield in subsequent integrated circuit manufacturing processes.
[0059] It is understood that those skilled in the art can combine various implementation methods in the above embodiments under the guidance of the above examples to obtain technical solutions with multiple implementation methods.
[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A production method for regulating monomer composition in a molecular chain of an ArF photoresist resin, characterized by, Comprising the following steps: S1) determining the types and proportions of monomers in the target resin molecular chain: the types of monomers are any two or three of monomers containing polar groups, monomers containing acid deprotection groups and monomers containing lactone groups, and the molar ratio of each monomer in the target resin molecular chain is monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a0:b0:c0; S2) dividing the weight of each monomer into two parts, the first part weight as the bottom liquid, and the second part weight added to the reaction system in a dropwise manner, wherein the first part weight accounts for 10%-20% of the total weight of each monomer: Mixing the first part weight of each monomer with the first solvent uniformly as the reaction bottom liquid, wherein according to the different reaction rates of each monomer, taking the molar ratio of each monomer in the target resin molecular chain as the basis, i.e. monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a0:b0:c0, increasing the proportion of monomers with slower reaction rate and decreasing the proportion of monomers with faster reaction rate, so that the molar ratio of each monomer in the reaction bottom liquid is monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a1:b1:c1, to ensure that in the initial stage of dropwise reaction, the resin molecules formed by polymerization in the reaction bottom liquid are composed of target monomers a0:b0:c0, and maintain relative balance with unreacted monomers, and the molar ratio of unreacted monomers is monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a2:b2:c2; Heating the reaction bottom liquid to the initiator decomposition temperature; Adding the second part weight of each monomer and the initiator to the reaction bottom liquid in a separate manner at a constant rate, wherein the second part weight of each monomer accounts for 80%-90% of the total weight of each monomer, the molar ratio of each monomer is the same as the molar ratio of monomers in the target resin molecular chain, i.e. monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a0:b0:c0, and the dropwise time of each monomer is proportional to the reaction rate of each monomer, so that the monomer composition of the resin formed in the reaction bottom liquid is monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a0:b0:c0, the molar ratio of unreacted monomers is monomers containing polar groups:monomers containing acid deprotection groups:monomers containing lactone groups=a2:b2:c2, and it is always kept in dynamic balance; after the dropwise addition of all monomers and initiators is completed, the reaction is terminated immediately; S3: cooling the reaction liquid; S4: removing the unreacted monomers and the polymerized resin in the reaction liquid by solid-liquid separation after precipitation with a second solvent, taking the precipitate for vacuum drying to obtain a photoresist resin.
2. The preparation method for regulating monomer composition in a molecular chain of an ArF photoresist resin according to claim 1, characterized in that, The monomers containing polar groups are any one or mixture of several of the following structures: wherein: R9, R 12 , R 14 are H or CH3, R 10 , R 11 are C w H 2w , w is an integer from 0 to 4, R 13 is C x H 2x , x is an integer from 1 to 4, R 15 is C y H 2y+1 , and y is an integer from 0 to 4.
3. The preparation method for regulating monomer composition in a molecular chain of an ArF photoresist resin according to claim 1, characterized in that, The monomers containing acid deprotection groups are any one or mixture of several of the following structures: wherein: R1, R3, R5, R7are H or CH3, R2, R4, R 6、 R8is C v H 2v+1 and v is an integer from 0 to 4.
4. The preparation method for regulating monomer composition in a molecular chain of an ArF photoresist resin according to claim 1, characterized in that, The monomers containing lactone groups are any one or mixture of several of the following structures: wherein: R 16 , R 18 , R 20 is H or CH3, R 17 , R 19 , R 21 is C z H 2z , and z is an integer from 1 to 4.
5. The method of claim 1, wherein the ArF photoresist resin is prepared by the steps of: (a) dissolving a monomer mixture in a solvent; (b) adding a polymerization initiator to the monomer mixture; (c) polymerizing the monomer mixture; (d) removing the solvent; and (e) purifying the ArF photoresist resin. The first part weight accounts for 12%-20% of the total weight of each monomer; preferably, the first part weight accounts for 15%-18% of the total weight of each monomer.
6. The method of claim 1, wherein the ArF photoresist resin is prepared by the steps of: (a) dissolving a monomer mixture in a solvent; (b) adding a polymerization initiator to the monomer mixture; (c) polymerizing the monomer mixture; (d) removing the solvent; and (e) purifying the ArF photoresist resin. The first solvent is one or a mixture of several of propylene glycol methyl ether acetate, tetrahydrofuran, 2-butanone, propylene glycol methyl ether, dichloromethane.
7. The method of claim 1, wherein the ArF photoresist resin is prepared by the steps of: (a) dissolving a monomer mixture in a solvent; (b) adding a polymerization initiator to the monomer mixture; (c) polymerizing the monomer mixture to form a polymer; (d) removing the solvent from the polymer; and (e) purifying the polymer. The initiator is one of azobisisobutyronitrile, azobisisoheptyl nitrile, azobisisopentyl nitrile and dimethyl azobis isobutyrate.
8. The method of claim 1, wherein the ArF photoresist resin is prepared by the steps of: (a) dissolving a monomer mixture in a solvent; (b) adding a polymerization initiator to the monomer mixture; (c) polymerizing the monomer mixture; (d) removing the solvent; and (e) purifying the ArF photoresist resin. The initiator dropping time is 3h-6h, preferably 3h-4h.
9. The method of claim 1, wherein the ArF photoresist resin is prepared by the steps of: (a) dissolving a monomer mixture in a solvent; (b) adding a polymerization initiator to the monomer mixture; (c) polymerizing the monomer mixture to form a polymer; (d) removing the solvent from the polymer; and (e) purifying the polymer. The second part of each monomer by weight, initiator is separately added to the reaction bottom liquid at a constant rate, the dropping time of the monomer containing polar group, the monomer containing acid deprotection group, the monomer containing lactone group is independently 0.8-1.2 times of the initiator dropping time.
10. A photoresist resin characterized by comprising: The photoresist resin is prepared by the preparation method of claim 1-9. The photoresist resin is prepared by the preparation method of claim 1-9.