Photoresist regeneration method and photoresist

Abstract

The invention relates to a photoresist regeneration method and photoresist, and relates to the technical field of photoresist, the method comprises the following steps: S1, filtering and collecting waste photoresist; s2, testing the viscosity of the filtered waste photoresist, and determining the difference value between the actual viscosity value of the waste photoresist and the viscosity standard of the regenerated photoresist; s3, firstly adding a proper amount of diluent into the waste photoresist, testing the exposure light intensity of the waste photoresist in which only the diluent is added, determining the difference value between the exposure light intensity and the exposure light intensity standard of the regenerated photoresist, and then adding a proper amount of photosensitizer; and S4, fully mixing a diluent and a photosensitizer with the waste photoresist to obtain the regenerated photoresist. According to the regeneration method, the waste photoresist can be effectively recycled, secondary use is realized on the basis of ensuring the performance of the regenerated photoresist, the regenerated photoresist can maintain the performance similar to that of the regenerated photoresist through testing and adjustment of the additive, the production requirements can be met, and particularly, the usability of the regenerated photoresist in actual production is ensured on the aspects of viscosity and photoreaction performance.

Description

Technical Field

[0001] The present application relates to the field of photoresist technology, and particularly to a photoresist regeneration method and a photoresist. Background Art

[0002] Photoresist is a key material used for patterning the surface of chips in the semiconductor manufacturing process, and is widely used in the production processes of integrated circuits (ICs), LCD panels, and other microelectronic products. The coating process of photoresist usually adopts Spin coating or Roller coating methods. Although these processes can coat the photoresist quickly and evenly, during use, the utilization rate of photoresist is low, resulting in a large amount of waste of photoresist.

[0003] Especially in the LCD panel manufacturing industry, during the coating process of photoresist, usually less than 30% of the photoresist is effectively utilized, and the remaining 70% of the photoresist is usually regarded as waste due to insufficient use. In order to reduce production costs and improve the utilization efficiency of resources, how to recycle and reuse these waste photoresists has become an urgent problem to be solved.

[0004] In the prior art, waste photoresist is usually not recycled but treated as waste, resulting in a large amount of waste of resources. Although some technologies attempt to dilute the remaining photoresist by adding a diluent for better coating, most of these solutions fail to solve the problem of reusing waste photoresist, and there is still a large amount of waste of photoresist.

[0005] Therefore, it is urgent to develop a technical solution that can recycle and effectively reuse waste photoresist, which can enable waste photoresist to achieve the effect of secondary use while maintaining its performance, thereby reducing the waste of photoresist, lowering production costs, and improving the utilization rate of resources. Summary of the Invention

[0006] In order to enable waste photoresist to achieve the effect of secondary use while maintaining its performance, the present application provides a photoresist regeneration method and a photoresist.

[0007] The photoresist regeneration method and photoresist provided by the present application adopt the following technical solutions: A photoresist regeneration method includes the following steps: S1. Filter and collect the waste photoresist; S2. Test the viscosity of the filtered waste photoresist to determine the difference between the actual viscosity value of the waste photoresist and the viscosity standard of the regenerated photoresist; S3. First add an appropriate amount of diluent to the waste photoresist, test the exposure light intensity of the waste photoresist with only the diluent added to determine the difference between it and the exposure light intensity standard of the regenerated photoresist, and then add an appropriate amount of photosensitizer; S4. Thoroughly mix and stir the diluent and the photosensitizer with the waste photoresist to obtain a regenerated photoresist.

[0008] By adopting the above technical solution, this method for regenerating photoresist can effectively recycle waste photoresist, realize its secondary use on the basis of ensuring the performance of the regenerated photoresist. Through viscosity testing, adjustment of diluent and photosensitizer, etc., the quality of the regenerated photoresist can be controlled. Adding diluent can control the viscosity of the waste photoresist and restore it to an appropriate range. Adding photosensitizer can ensure that the regenerated photoresist has sufficient photosensitivity, ensuring that the exposure performance of the regenerated photoresist is close to that of the original photoresist, so as to meet the standards of different production requirements, ensure the consistency and repeatability of the regenerated photoresist. By recycling and regenerating waste photoresist, the treatment cost and environmental pollution of waste photoresist are reduced. This not only improves the resource utilization rate, but also reduces the demand for regenerated photoresist, helps to reduce production costs. The regenerated photoresist can maintain similar performance to the original photoresist, especially in terms of viscosity and photoreaction performance, ensuring its usability in actual production and avoiding product quality fluctuations caused by performance differences.

[0009] In a specific feasible implementation, the calculation formula for the addition amount of the diluent is: for every 0.5 cP increase in the actual viscosity value of the waste photoresist compared to the viscosity standard of the regenerated photoresist, 70 ml of diluent is added.

[0010] By adopting the above technical solution, through the above calculation and the process of adding diluent, the viscosity of the waste photoresist can be accurately controlled to meet the standard requirements of the regenerated photoresist, so as to ensure that the performance of the waste photoresist is not affected, enabling it to reach the same quality standard as the regenerated photoresist, ensuring that the performance such as the resolution and contrast of the photolithography pattern will not be negatively affected by viscosity changes, and ensuring its smooth application in the photolithography process.

[0011] In a specific feasible implementation, in S3, after adding the diluent, measure the exposure light intensity of the waste photoresist with only the diluent added and compare it with the exposure light intensity standard of the regenerated photoresist; if the light intensity attenuation is within 15% of the exposure light intensity standard of the regenerated photoresist, quantitatively compensate 10 ml of photosensitizer. If the light intensity attenuation exceeds 15% of the exposure light intensity standard of the regenerated photoresist, for every additional 5% increase in light intensity attenuation, the addition amount of the photosensitizer is increased by 50% on the basis of the original quantitative addition.

[0012] By adopting the above technical solution, by dynamically adjusting the addition amount of the photosensitizer according to the specific situation of light intensity attenuation, the adjustment of photosensitivity can be more accurately controlled, avoiding over - addition or under - addition, ensuring that the performance of the waste photoresist can be restored and approach that of the regenerated photoresist, improving the waste utilization rate, saving costs, and at the same time ensuring the stability of the photolithography process and product quality.

[0013] In a specific feasible implementation, the viscosity value standard of the recycled photoresist is 15 ± 1 cP, and the light intensity standard for the recycled photoresist exposure is 50 - 80 mj / cm 2 .

[0014] In a specific feasible implementation, the diluent is one of propylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, and ethyl lactate.

[0015] By adopting the above technical solutions, the above diluents can effectively adjust the viscosity of the photoresist to make it suitable for coating and exposure, ensure that the photoresist can be evenly coated on the surface of the substrate, and have a moderate evaporation rate, which can provide sufficient operation time to avoid premature drying of the photoresist, thereby ensuring a better film-forming effect and controllability of the coating process; it also helps the photoresist to form a stable and uniform film layer, avoid problems during the film-forming process, and improve the accuracy and clarity of the photolithography effect.

[0016] In a specific feasible implementation, the photosensitizer is one of diazonaphthoquinone, trifluoromethanesulfonate salt, diaryliodonium salt, and carbamate compounds.

[0017] By adopting the above technical solutions, the above photosensitizers enable the photoresist to have good exposure controllability. Acidic substances can be generated by ultraviolet light irradiation, and these acidic substances can trigger the cross-linking reaction of the photoresist resin. The cross-linked resin area becomes less soluble, while the unexposed area remains soluble. Under certain exposure conditions, the formation of the pattern can be precisely controlled to ensure the clarity and accuracy of the pattern.

[0018] In a specific feasible implementation, in S1, a filter element with a size of 0.1 - 0.5 um is used to filter and collect the waste photoresist.

[0019] By adopting the above technical solutions, using a filter element with a size of 0.1 - 0.5 um to filter and collect the waste photoresist can effectively remove solid particles, unreacted photosensitizers, impurities, or other particles that may affect the photolithography effect in the waste photoresist, improve the quality and consistency of the photoresist, ensure that the photoresist has relatively uniform and stable performance when reused, and improve the accuracy and consistency of the photoresist.

[0020] A photoresist is prepared by the method described above.

[0021] By adopting the above technical solutions, using the above method, including steps such as filtration, viscosity testing, and regeneration treatment of waste photoresist, the finally obtained recycled photoresist can restore its performance and meet the requirements of the photolithography process. It can not only effectively recycle waste photoresist and reduce waste, but also ensure that it does not affect the subsequent photolithography quality and equipment stability during the reuse process.

[0022] In summary, the beneficial technical effects of this application are as follows: Through precise calculation and control of the addition amounts of diluent and photosensitizer, as well as a series of steps for the regeneration method, the efficient regeneration of waste photoresist has been successfully achieved; the entire process includes the filtration, viscosity testing, precise addition of diluent and photosensitizer, and performance optimization of waste photoresist; through this method, the performance of the regenerated photoresist can be precisely adjusted to be similar to that of the regenerated photoresist in terms of viscosity, photosensitivity, etc., thereby ensuring its stability and consistency in actual production; not only improving the resource utilization rate of waste photoresist, reducing production costs, but also reducing environmental pollution, providing an effective solution for the sustainable development of the photoresist industry. Description of the Drawings

[0023] Figure 1 is a flowchart of the photoresist regeneration method according to an embodiment of this application. Detailed Embodiments

[0024] An embodiment of this application discloses a photoresist regeneration method. By recycling, processing, adjusting the viscosity, and adding necessary additives to waste photoresist, the regenerated photoresist can achieve performance similar to that of the regenerated photoresist, while reducing costs, improving resource utilization rate, and reducing the impact on the environment. Through viscosity testing, additive control, and adjustment of photosensitive performance, it can be ensured that the regenerated photoresist has consistency, stability, and reliability in actual production.

[0025] Refer to Figure 1 , a photoresist regeneration method, including the following steps: Step S1: Filtration and collection of waste photoresist Perform a filtration and collection operation on the waste photoresist generated after coating; the waste photoresist comes from the waste generated during the photolithography process or the excess unreacted photoresist after coating. To ensure the quality of the regenerated photoresist, it is first necessary to remove solid particles, unreacted photosensitizer, and other impurities in the waste photoresist; in this embodiment, a filter element with a pore size of 0.1 - 0.5 um is used to filter the waste photoresist. Preferably, a filter element with a pore size of 0.2 um is used to filter the waste photoresist. During the filtration process, the 0.2 - um filter element can effectively remove solid particles, unreacted photosensitizer, impurities, or other particles that may affect the photolithography effect in the waste photoresist, ensuring the uniformity and purity of the photoresist, and providing high - quality raw materials for subsequent regeneration treatment.

[0026] The specific operation of filtration and collection is as follows: 1. Equipment preparation: Use a recycling bottle with sufficient volume (e.g., a container of 2L or larger), and install a 0.2um filter element at the mouth of the recycling bottle. The filter element can be a circular or flat filter membrane, and materials such as polytetrafluoroethylene (PTFE) or nylon, which are resistant to chemical corrosion, can be selected.

[0027] 2. Connect the conduit: Transport the waste photoresist to the recycling bottle through a transparent hose or conduit. One end of the inflow pipe of the waste photoresist should be connected to the waste source (such as a waste photoresist barrel), and the other end should be connected to the recycling bottle. A valve can be set at the end of the conduit to control the flow rate.

[0028] 3. Filtration operation: Open the valve and let the waste photoresist slowly flow into the recycling bottle. During the inflow process, the waste photoresist is filtered through the 0.2um filter element. The role of the filter element is to remove solid particles, impurities, and unreacted photosensitizers in the waste photoresist, ensuring that the finally recycled photoresist has high purity and uniformity.

[0029] 4. Recycling process: The filtered waste photoresist flows into the recycling bottle through the filter element, while the solid impurities are intercepted on the surface of the filter membrane by the filter element. When the waste photoresist in the recycling bottle reaches the required amount, close the valve to stop the filtration operation, remove the conduit and filter element for cleaning, and complete the filtration and collection of the waste photoresist.

[0030] Step S2: Viscosity test Conduct a viscosity test on the filtered waste photoresist to determine the actual viscosity value of the waste photoresist; the specific viscosity requirement is that the viscosity value of the recycled photoresist should be 15±1cP. After measuring the actual viscosity value of the waste photoresist, make corresponding adjustments according to the deviation between this value and the required viscosity value of the recycled photoresist to ensure that the viscosity of the finally recycled photoresist is appropriate.

[0031] To accurately test the viscosity, a standard viscometer can be used for measurement. The specific operation is as follows: 1. Equipment preparation: Prepare a standard rotational viscometer, such as a Brookfield viscometer, select a suitable viscometer rotor, and it is recommended to use a digital display type viscometer, which has high precision and sensitivity.

[0032] 2. Sampling of waste photoresist: Take an appropriate amount of the filtered waste photoresist and pour it into a clean and dry beaker or container. The beaker should have a certain measuring range to ensure that the measurement process is not restricted, usually with a volume of 100 - 200ml.

[0033] 3. Operation of the viscometer: Insert the rotor of the viscometer into the waste photoresist sample, ensuring that the rotor is completely immersed in the glue and avoiding contact with the container wall. Start the viscometer and set an appropriate rotation speed. Read the actual viscosity value of the waste photoresist according to the instrument display, ensuring a stable measurement time and avoiding external vibration interference.

[0034] 4. Record data: The viscometer will display the viscosity value of the waste photoresist. Record the measured actual viscosity and compare it with the standard viscosity of the regenerated photoresist (15 ± 1 cP). If the viscosity value deviates significantly, adjustments need to be made according to the subsequent steps.

[0035] Step S3: Add additives Add a certain amount of additives to the waste photoresist. In this embodiment, the additives include a diluent and a photosensitizer. According to the viscosity test results, make appropriate adjustments to the actual viscosity of the waste photoresist. The diluent is used to adjust the viscosity of the waste photoresist to restore it to the viscosity range of the regenerated photoresist, and the photosensitizer ensures that the regenerated photoresist has sufficient photosensitivity to ensure that the exposure performance is close to that of the regenerated photoresist.

[0036] Adding an appropriate amount of additives (including a diluent and a photosensitizer) to the waste photoresist is a key step to ensure its restoration of the performance of the regenerated photoresist. The specific operation is as follows: Select a suitable diluent. In this embodiment, the diluent includes one of propylene glycol monomethyl ether acetate (PGMEA), ethylene glycol monoethyl ether acetate (EGMEA), or ethyl lactate. In this embodiment, propylene glycol monomethyl ether acetate is preferably selected as the diluent. PGMEA can effectively dissolve various chemical substances, has good compatibility with other chemicals, can be used in combination with different types of photoresists, and its evaporation rate is moderate, which can maintain enough time for coating and processing without evaporating too quickly. In addition, PGMEA can help form a uniform and smooth film during the coating process. Especially in the lithography process, it can provide appropriate solubility and the ability to control the coating thickness, improving the clarity and accuracy of the final pattern.

[0037] According to the difference between the actual viscosity value of the waste photoresist measured in step S2 and the viscosity requirement of the regenerated photoresist, calculate the required amount of diluent. By adjusting the addition amount, the viscosity of the waste photoresist can be effectively controlled to restore it to a suitable coating range.

[0038] The relationship between the viscosity of the waste photoresist and the standard viscosity of the regenerated photoresist is: for every 0.5 cP increase in the measured viscosity of the waste photoresist compared to the standard viscosity of the regenerated photoresist, add 70 ml of diluent. That is, the addition amount of the diluent can be calculated by the following formula: Diluent addition amount (ml) = (waste photoresist viscosity - regenerated photoresist standard viscosity) / 0.5 × 70 diluent addition amount (ml) That is: V = 0.5(η_waste - η_new)×70 ml Wherein, V is the addition amount of the diluent; η_waste is the actual viscosity value of the waste photoresist measured; η_new is the standard viscosity value of the regenerated photoresist.

[0039] This formula can calculate the required amount of diluent according to the difference between the actually measured viscosity value of the waste photoresist and the standard viscosity value of the regenerated photoresist, ensuring that the viscosity of the waste photoresist is restored to the standard range.

[0040] According to the addition amount of the diluent calculated by the formula, propylene glycol monomethyl ether acetate (PGMEA) is added to the waste photoresist.

[0041] 2. Selection and addition of photosensitizer: The addition amount of the photosensitizer needs to be adjusted according to the light intensity attenuation of the waste photoresist. Usually, after adding the diluent, the exposure performance of the waste photoresist is evaluated through an exposure test, and the exposure performance of the waste photoresist is compared with the exposure standard of the regenerated photoresist. In this embodiment, the light intensity standard for the regenerated photoresist exposure is 50 - 80 mj / cm 2 . The specific steps for adding the photosensitizer are as follows: a. Evaluation of exposure performance: After adding the diluent, first, the exposure performance of the waste photoresist with only the diluent added needs to be evaluated through an exposure test. The purpose of the exposure test is to measure the light intensity attenuation of the waste photoresist with only the diluent added after exposure, and determine the addition amount of the photosensitizer according to the attenuation situation.

[0042] b. Steps for light intensity attenuation test: Prepare the sample: Uniformly coat the treated waste photoresist on a suitable substrate (such as a silicon wafer or a glass slide). During the coating process, ensure that the coating is uniform and free of bubbles.

[0043] Exposure equipment setting: Use a lithography machine or other suitable ultraviolet (UV) exposure equipment, set the exposure wavelength to 365 nm, and the exposure light intensity to 50 - 80 mj / cm 2 .

[0044] Exposure process: Place the substrate coated with the waste photoresist into the exposure machine and perform a standard exposure operation.

[0045] Test the light intensity after exposure: Evaluate the exposure performance of the waste photoresist by measuring the attenuation of the light intensity after exposure.

[0046] c. Relationship between light intensity attenuation and photosensitizer addition Within 15% attenuation: If the light intensity attenuation after exposure is within the light intensity standard for the regenerated photoresist exposure (50 - 80 mj / cm 2If it is within 15% of the range, it indicates that the exposure performance of the waste photoresist is good and there is no need to significantly increase the photosensitizer. In this case, add 10 ml of photosensitizer.

[0047] Attenuation exceeding 15%: If the light intensity attenuation after exposure exceeds 15% of the light intensity standard for exposing the recycled photoresist, for every 5% increase in light intensity attenuation, the addition amount of the photosensitizer needs to be increased. The specific calculation method is as follows: If the light intensity attenuation exceeds 15%, for every 5% increase in light intensity attenuation, the addition amount of the photosensitizer is increased by 50% based on the original fixed amount; for example, if the light intensity attenuation is 20%, the addition amount of the photosensitizer needs to be increased by 50% based on the original fixed amount, which is 15 ml (original fixed amount 10 ml + 50% increase).

[0048] d. Selection and operation of photosensitizer The selection of the photosensitizer includes one of diazonaphthoquinone (DNQ), trifluoromethanesulfonate (TFPB), diaryliodonium salt (DPI), and carbamate compounds (NCO). In this embodiment, the photosensitizer is preferably diazonaphthoquinone. DNQ can react quickly under ultraviolet light irradiation, change the solubility of the coating, is beneficial to pattern transfer, can form clear and fine patterns during the lithography process, and has good chemical stability when not exposed, ensuring operation safety. In addition, DNQ can be compatible with other materials and coatings, ensuring consistent performance, and can also improve the corrosion resistance and keep the pattern clear; According to the light intensity attenuation situation after the exposure test, prepare the corresponding amount of diazonaphthoquinone photosensitizer and add it to the waste photoresist.

[0049] Step S4: Mix and stir thoroughly Fully mix the diluent, photosensitizer, and waste photoresist to obtain the recycled photoresist; in order to ensure the complete fusion of the waste photoresist and additives and guarantee the quality of the recycled photoresist, use a special spin coater to fully mix the diluent, photosensitizer, and waste photoresist. The mixed waste photoresist can be further stirred. The specific operation is as follows: 1. Use a high-efficiency stirrer: If the capacity of the stirrer is insufficient to ensure complete mixing, a high-shear stirrer or an ultrasonic stirrer can be used to ensure the full fusion of the waste photoresist with the diluent and photosensitizer.

[0050] 2. Stirring time: The mixing time is usually 20 to 30 minutes to ensure uniformity and avoid the formation of precipitates. During the mixing process, the temperature should be kept at room temperature or a lower temperature to avoid the volatilization of additives or the change in the properties of the photoresist caused by excessive temperature.

[0051] 3. Visual inspection: During the mixing process, regularly check whether the appearance of the photoresist is uniformly transparent, ensuring no bubbles or precipitates. Any non-uniformity should be stirred again.

[0052] During the mixing process, it is recommended to use low temperature or room temperature conditions to avoid component volatilization or damage caused by high temperature; the mixing should ensure that the waste photoresist and additives can be fully integrated to form a regenerated photoresist.

[0053] Step S5: Viscosity and performance testing of the regenerated photoresist Test the viscosity of the regenerated photoresist to ensure it meets the standards of the regenerated photoresist, and then proceed with production; the regenerated photoresist after sufficient mixing needs to be subjected to viscosity testing and exposure performance verification to ensure it meets the production requirements. The specific operations are as follows: 1. Viscosity testing: Use a viscometer to measure the viscosity of the regenerated photoresist again to ensure it is within the range of 15 ± 1 cP; if the viscosity exceeds the standard range, an appropriate amount of diluent needs to be added for adjustment.

[0054] 2. Exposure performance testing: Coat the regenerated photoresist on the surface of a suitable substrate and conduct a photolithography exposure test. By comparing the performance such as pattern resolution, contrast, and clarity after exposure, evaluate whether the regenerated photoresist meets the standards of the regenerated photoresist.

[0055] 3. Light intensity attenuation testing: During the exposure process, monitor the light intensity attenuation; if the light intensity attenuation exceeds 15%, the addition amount of the photosensitizer needs to be further adjusted according to the attenuation amount to ensure that the exposure performance meets the standards.

[0056] 4. Final confirmation: Finally, confirm that the performance of the regenerated photoresist is consistent with that of the regenerated photoresist. After meeting the production requirements, it can be put into actual production use.

[0057] In order to verify the influence of the key technical features of the diluent and photosensitizer in this patent on the performance of the regenerated photoresist, the following examples and comparative examples were designed; through viscosity testing, additive control, and adjustment of photosensitive performance, ensure the consistency, stability, and reliability of the regenerated photoresist in actual production.

[0058] Examples 1 - 12: Regeneration treatment of waste photoresists with different viscosities Design 12 groups of waste photoresists with different viscosity values, and calculate the required amounts of diluent and photosensitizer to be added for waste photoresists with different viscosities respectively.

[0059] Experimental steps: 1. Waste photoresist filtration: Filter the waste photoresist using a 0.2um filter element, with a filtration pressure of 0.2MPa and a filtration speed of 15L / min.

[0060] 2. Viscosity test: Use a rotational viscometer to test the viscosity of the filtered waste photoresist and record the actual viscosity value.

[0061] 3. Diluent addition: In this embodiment, calculate according to the viscosity standard of the regenerated photoresist being 15cP. Based on the actual viscosity value of the waste photoresist, calculate and add PGMEA at a ratio of increasing 70ml of PGMEA for every 0.5cP increase in viscosity.

[0062] 4. Sensitizer addition: Evaluate the exposure performance of the waste photoresist through an exposure test. In this embodiment, calculate according to the light intensity standard for exposure of the regenerated photoresist being 65mj / cm 2 If the light intensity attenuation after exposure is within 15% of the light intensity standard for exposure of the regenerated photoresist, 10ml of sensitizer can be quantitatively added; if the light intensity attenuation exceeds 15%, for every 5% increase in light intensity attenuation, the addition amount of the sensitizer increases by 50% on the original quantitative basis.

[0063] 5. Mixing and viscosity test: Thoroughly mix the additives with the waste photoresist at a mixing speed of 150rpm for 15 minutes; after mixing, test the viscosity of the regenerated photoresist to ensure that its viscosity value meets the viscosity standard of the regenerated photoresist (15±1cP), and ensure that its exposure light intensity meets the light intensity standard for exposure of the regenerated photoresist (50 - 80mj / cm 2 )

[0064] 6. Static storage test: Store the regenerated photoresist statically in an environment of 23±0.5°C for 12 hours and observe its stability.

[0065] Comparative Examples 1 - 3: Comparative experiments with different sensitizer addition amounts The differences from Examples 1 - 12 are as follows: 3. Diluent addition: Take waste photoresist with the same viscosity value, calculate the addition amount of the PGMEA diluent according to the calculation formula, and design the comparative examples to add the same amount of PGMEA according to the calculated addition amount.

[0066] 4. Sensitizer addition: Add 5ml, 10ml, and 15ml of DNQ sensitizer respectively, and observe the influence of the sensitizer addition amount on the performance of the regenerated photoresist.

[0067] Comparative Examples 4 - 6 The differences from Examples 1 - 12 are as follows: 3. Diluent addition: Take waste photoresist with the same viscosity value, and design comparative examples to add different amounts of PGMEA diluent respectively, and observe the influence of different diluent addition amounts on the performance of the regenerated photoresist.

[0068] 4. Sensitizer addition: Add the same fixed amount of DNQ sensitizer; specifically evaluate the exposure performance of the waste photoresist through exposure tests. If the light intensity attenuation after exposure is within 15%, 10 ml of sensitizer can be added quantitatively; if the light intensity attenuation exceeds 15%, for every 5% increase in light intensity attenuation, the quantitative addition of the sensitizer increases by 50%.

[0069] Please refer to Table 1 for the test results: Table 1 Data description: 1. Measured viscosity: The measured viscosities of Examples 1 - 12 are between 14.5 cP and 15.6 cP, all meeting the viscosity standard of the regenerated photoresist (15 ± 1 cP).

[0070] The measured viscosities of Comparative Example 3 and Comparative Example 4 are 17.0 cP and 13.0 cP respectively, exceeding the standard range, indicating that insufficient or excessive diluent addition will affect the viscosity of the regenerated photoresist.

[0071] 2. Photosensitivity (light intensity): The photosensitivities of Examples 1 - 12 are between 57 - 68 mj / cm 2 and all meet the light intensity standard of the regenerated photoresist (50 - 80 mj / cm 2 ).

[0072] The photosensitivities of Comparative Example 1 and Comparative Example 2 are 45 mj / cm 2 and 85 mj / cm 2 respectively, exceeding the standard range, indicating that insufficient or excessive sensitizer addition will affect the photosensitivity of the regenerated photoresist.

[0073] 3. Static storage stability: The regenerated photoresists of all examples and comparative examples can remain stable after 12 hours of static storage, indicating its high reliability during the production process.

[0074] This application has successfully achieved the efficient regeneration of waste photoresist by precisely controlling the addition amounts of diluent and sensitizer, ensuring that the regenerated photoresist has similar performance to the regenerated photoresist in actual production. The specific conclusions are as follows: 1. Selection of diluent and precise control of addition amount Diluent Selection: In this application, PGMEA (propylene glycol methyl ether acetate) is selected as the diluent. It has good solubility and volatility, can effectively adjust the viscosity of the photoresist, and ensure the coating uniformity and film-forming quality of the regenerated photoresist.

[0075] Additive Amount Control: Calculated according to the viscosity standard of the regenerated photoresist being 15 cP, for every 0.5 cP increase in viscosity value, the proportion of 70 ml of PGMEA is increased for addition. Through this calculation method, the viscosity of the regenerated photoresist can be precisely adjusted to meet the standard viscosity of the final regenerated photoresist (15 ± 1 cP). The measured viscosities of Examples 1 - 12 are all between 14.5 cP and 15.6 cP, indicating that this calculation method has high reliability and consistency.

[0076] 2. Selection of Photosensitizer and Dynamic Adjustment of Additive Amount Photosensitizer Selection: In this application, DNQ (diazonaphthoquinone) is selected as the photosensitizer. It has good photosensitivity and exposure controllability, and can ensure that the photosensitive performance of the regenerated photoresist is close to that of the regenerated photoresist.

[0077] Additive Amount Control: The exposure performance of the waste photoresist is evaluated through exposure tests, and the additive amount of the photosensitizer is dynamically adjusted. The specific method is as follows: Calculated according to the standard light intensity for exposure of the regenerated photoresist being 65 mj / cm 2 When the light intensity attenuation is within 15%, 10 ml of the photosensitizer is added quantitatively; when the light intensity attenuation exceeds 15%, for every 5% increase in light intensity attenuation, the additive amount of the photosensitizer is increased by 50%. This method can ensure that the photosensitive performance of the final regenerated photoresist meets the standard of the regenerated photoresist (50 - 80 mj / cm 2 )). The photosensitive performances of Examples 1 - 12 are all between 57 - 68 mj / cm 2 indicating that this dynamic adjustment method has high accuracy and operability.

[0078] 3. Performance and Stability of the Regenerated Photoresist Performance Consistency: It can be seen from the experimental data of Examples 1 - 12 that the viscosity and photosensitive performance of the regenerated photoresist are both consistent with the standards of the regenerated photoresist, indicating that this application can ensure that the regenerated photoresist has high consistency and reliability in actual production.

[0079] Static Storage Stability: The regenerated photoresists of all examples and comparative examples can remain stable after being statically stored for 12 hours, indicating that it has high stability during the production process and can meet the requirements of actual production.

[0080] 4. Beneficial Effects of This Application Cost reduction: By recycling and regenerating waste photoresist, the demand for regenerated photoresist is significantly reduced, and the production cost is decreased. According to the data of the examples, the performance of the regenerated photoresist is consistent with that of the recycled photoresist and can directly replace the recycled photoresist for use.

[0081] Improving resource utilization rate: By recycling waste photoresist and performing regeneration treatment, the utilization rate of photoresist is significantly increased, and resource waste is reduced. The experimental data of Examples 1-12 show that the utilization rate of the regenerated photoresist is close to 100%, much higher than 30% of the traditional process.

[0082] Reducing environmental pollution: By recycling and regenerating waste photoresist, the amount of waste photoresist to be treated is reduced, and environmental pollution is decreased. This application not only has economic benefits but also significant environmental protection benefits.

[0083] 5. Verification of comparative examples Comparative examples 1-2: By comparing the experimental results of different photosensitizer addition amounts, the influence of the photosensitizer addition amount on the photosensitive performance of the regenerated photoresist was verified. The photosensitive performances of Comparative Example 1 (5 ml DNQ) and Comparative Example 2 (15 ml DNQ) were 45 mj / cm 2 and 85 mj / cm 2 , respectively, exceeding the standard range, indicating that precise control of the photosensitizer addition amount is crucial for the performance of the regenerated photoresist.

[0084] Comparative examples 3-4: By comparing the experimental results of different diluent addition amounts, the influence of the diluent addition amount on the viscosity of the regenerated photoresist was verified. The measured viscosities of Comparative Example 3 (2500 ml PGMEA) and Comparative Example 4 (3500 ml PGMEA) were 17.0 cP and 13.0 cP, respectively, exceeding the standard range, indicating that precise control of the diluent addition amount is crucial for the viscosity adjustment of the regenerated photoresist.

[0085] This application has successfully achieved the efficient regeneration of waste photoresist by precisely controlling the addition amounts of the diluent and the photosensitizer, ensuring that the regenerated photoresist has similar performance to the recycled photoresist in actual production. This application not only reduces production costs, improves resource utilization rate, but also reduces environmental pollution, having significant economic and environmental protection benefits. Through the experimental data of the examples and comparative examples, the effectiveness and feasibility of this application are fully verified, providing an efficient and reliable solution for the recycling and utilization of photoresist.

[0086] The above are all the preferred embodiments of this application. The protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A photoresist regeneration method, characterized in that: The following steps are involved: S1, filtering and collecting the waste photoresist; S2, performing a viscosity test on the filtered waste photoresist to determine the difference between the actual viscosity value of the waste photoresist and the viscosity standard of the regenerated photoresist; S3, first adding a proper amount of diluent to the waste photoresist, testing the exposure light intensity of the waste photoresist with only the diluent added, determining the difference between the exposure light intensity of the waste photoresist and the exposure light intensity standard of the regenerated photoresist, and then adding a proper amount of photosensitizer; S4, fully mixing and stirring the diluent and the photosensitizer with the waste photoresist to obtain regenerated photoresist.

2. The photoresist regeneration method according to claim 1, characterized in that: The calculation formula for the amount of the diluent to be added is: for every 0.5 cP that the actual viscosity value of the waste photoresist is higher than the viscosity standard of the regenerated photoresist, add 70 ml of diluent.

3. The photoresist regeneration method according to claim 2, characterized in that: In S3, after adding the diluent, the light intensity for exposure of the waste photoresist with only the diluent added is tested, and the light intensity is compared with the light intensity standard for exposure of the regenerated photoresist; If the light intensity attenuation is within 15% of the light intensity standard for regenerated photoresist exposure, 10 ml of photosensitive agent is quantitatively compensated. If the light intensity attenuation exceeds 15% of the light intensity standard for regenerated photoresist exposure, the amount of photosensitive agent added is increased by 50% on the original quantitative basis for every 5% increase in light intensity attenuation.

4. The photoresist regeneration method according to claim 3, characterized in that: The viscosity value standard of the regenerated photoresist is 15±1cP, and the light intensity standard for exposure of the regenerated photoresist is 50-80mj / cm 2 .

5. The photoresist regeneration method according to claim 1, characterized in that: The diluent is one of propylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, and ethyl lactate.

6. The photoresist regeneration method according to claim 1, characterized in that: The photosensitizer is one of naphthoquinone diazide, potassium trifluorosulfonium salt, diaryliodonium salt, and carbamate compound.

7. The photoresist regeneration method according to claim 1, characterized in that: In S1, a 0.1-0.5 um filter element is used to filter and collect the waste photoresist.

8. A photoresist, characterized in that: Prepared by the method described in any one of claims 1 to 7.

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