Antireflection coating and method for producing the same

Abstract

The application provides an antireflection coating and a preparation method thereof. The antireflection coating comprises a BARC main resin, a crosslinking agent, a heat-sensitive acid and a solvent. The mass ratio of the heat-sensitive acid to the BARC main resin is greater than 0 and less than 1. The mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100. The mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1. The oxygen content of the crosslinking agent determines the etching rate of the antireflection layer. The application only needs to adjust the oxygen content of the crosslinking agent in the antireflection coating, and then does not need to add an oxygen-containing functional group in the process of synthesizing the BARC main resin, so that the stable adjustment of the etching rate of the antireflection coating can be realized, the production efficiency of the antireflection coating is improved, and the production cost of the antireflection coating is reduced.

Description

Technical Field

[0001] This application belongs to the field of photoresist technology, and in particular relates to an anti-reflective coating and its preparation method. Background Technology

[0002] The bottom anti-reflection coating (BARC) is a coating located between the Si substrate and the photoresist. Its main components are cross-linkable resin, thermosetting acid generator, surfactant, and solvent. Different chip manufacturing processes and application scenarios have different etching performance requirements for the bottom anti-reflection coating.

[0003] In related technologies, when improving the etching performance of the bottom antireflective coating, oxygen-containing functional groups are usually added to the BARC base resin to enhance its etching performance. However, BARC base resins with a high oxygen content, such as acrylic resins with long ether chain side groups, often lead to problems such as high viscosity and low polymerization activity. Moreover, the etching performance of the bottom antireflective coating can only be controlled from the synthesis end of the BARC base resin, which is time-consuming, has a small adjustable range, and can also cause other properties of the BARC base resin to change. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this application provides an anti-reflective coating and its preparation method, aiming to solve the technical problem that the etching performance of the bottom anti-reflective coating cannot be stably adjusted in existing technologies.

[0005] To address the aforementioned problems, in a first aspect, this application provides an anti-reflective coating comprising: a BARC base resin, a crosslinking agent, a thermosensitive acid, and a solvent;

[0006] Wherein, the mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1, and the oxygen content of the crosslinking agent determines the etching rate of the antireflective layer; the mass ratio of the thermosensitive acid to the BARC main resin is greater than 0 and less than 1; and the mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100.

[0007] Furthermore, in the anti-reflective coating, the etching rate is 5-8 nm / min, and the mass ratio of the crosslinking agent to the BARC main resin is not less than 0.2 and not greater than 0.6.

[0008] Furthermore, in the antireflective coating, the crosslinking agent includes one or more of diol crosslinking agents, triol crosslinking agents, tetraol crosslinking agents, pentaol crosslinking agents, and hexaol crosslinking agents.

[0009] Furthermore, in the antireflective coating, the crosslinking agent is a polyol polymer.

[0010] Furthermore, in the antireflective coating, the degree of polymerization of the polyol polymer is 100-10000.

[0011] Furthermore, in the anti-reflective coating, the polyol polymer is one or more of polyethylene glycol and polypropylene glycol.

[0012] Furthermore, in the antireflective coating, the polymer includes one or more of polyethylene glycol 400, polyethylene glycol 1000, polyethylene glycol 4000, polyethylene glycol 10000, polypropylene glycol 400, polypropylene glycol 1000, polypropylene glycol 4000, and polypropylene glycol 10000.

[0013] Furthermore, in the anti-reflective coating, the refractive index of the anti-reflective layer is 1.75 to 1.85, and the absorbance of the anti-reflective layer is 0.3 to 0.5.

[0014] Furthermore, in the anti-reflective coating, the anti-reflective coating also includes a glycourea derivative, wherein the mass ratio of the glycourea derivative to the BARC main resin is greater than 0 and less than 1.

[0015] Secondly, this application also provides a method for preparing an anti-reflective coating, comprising:

[0016] The methacrylate monomer was polymerized to obtain the BARC main resin;

[0017] The BARC main resin, crosslinking agent, and thermosensitive acid are mixed in a preset ratio to obtain the anti-reflective coating;

[0018] Wherein, the mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1, and the oxygen content of the crosslinking agent determines the etching rate of the antireflective layer; the mass ratio of the thermosensitive acid to the BARC main resin is greater than 0 and less than 1; and the mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100.

[0019] The antireflective coating provided in this application comprises a BARC base resin, a crosslinking agent, a thermosensitive acid, and a solvent. The mass ratio of the thermosensitive acid to the BARC base resin is greater than 0 and less than 1, the mass ratio of the solvent to the BARC base resin is greater than 0 and less than 100, and the mass ratio of the crosslinking agent to the BARC base resin is greater than 0 and less than 1. The oxygen content of the crosslinking agent determines the etching rate of the antireflective layer. This application achieves stable adjustment of the etching rate of the antireflective coating simply by adjusting the oxygen content of the crosslinking agent, without adding oxygen-containing functional groups during the synthesis of the BARC base resin. Simultaneously, it ensures the stability of other properties of the antireflective coating (such as light absorption and solvent resistance), improving the production efficiency and reducing the production cost of the antireflective coating. Detailed Implementation

[0020] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] The anti-reflective coating provided in this application is mainly applied to the bottom anti-reflective coating, i.e., the coating located between the silicon substrate and the photoresist. It is primarily composed of resin, crosslinking agent, and solvent. In use, the bottom anti-reflective coating is applied to the silicon wafer or die first, and then photoresist is applied on top of this coating to reduce the amount of light reflected back to the photoresist layer from the silicon wafer or die surface. This reduces the standing wave effect, improves the edge morphology after photolithography, and finally removes it through etching. Therefore, the etching rate of the bottom anti-reflective coating is typically faster than that of the upper photoresist layer, exposing the underlying material of the wafer pattern after etching for subsequent processing.

[0025] The key properties of the bottom anti-reflective coating include light absorption, solvent resistance, and etching performance. Currently, in the process of improving the key properties of the bottom anti-reflective coating, different functional groups are usually added to the BARC base resin to improve these properties.

[0026] For example, adding benzene-containing functional groups to the BARC base resin can improve the light absorption performance of the bottom anti-reflective coating; or adding functional groups containing active groups to the BARC base resin and reacting them with a crosslinking agent can improve the solvent resistance performance of the bottom anti-reflective coating; or adding oxygen-containing functional groups to the BARC base resin can improve the etching performance of the bottom anti-reflective coating.

[0027] It is understandable that traditional bottom anti-reflective coatings are usually composed of a main resin, additives, and solvents. The composition of the main resin determines the etching resistance of the bottom anti-reflective coating. Therefore, the traditional method is to adjust the etching resistance by adjusting the component ratio during the synthesis of the BARC main resin. However, this method has a long preparation cycle, high cost, and a significant impact on other properties of the bottom anti-reflective coating.

[0028] Therefore, this application provides an anti-reflective coating comprising: BARC base resin, crosslinking agent, thermosensitive acid, and solvent;

[0029] Wherein, the mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1, and the oxygen content of the crosslinking agent determines the etching rate of the antireflective layer; the mass ratio of the thermosensitive acid to the BARC main resin is greater than 0 and less than 1; and the mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100.

[0030] Specifically, this application adjusts the etching rate of the bottom antireflective coating by adjusting the oxygen content of the crosslinking agent, eliminating the need to synthesize BARC main resin to adjust the etching rate of the bottom antireflective coating, thus saving the preparation time of the bottom antireflective coating. At the same time, it also allows the etching performance of the bottom antireflective coating to have a wider range of applications and can be used under different etching process conditions.

[0031] In this application, the amount of oxygen in the crosslinking agent that determines the etching rate of the antireflective layer can be determined by the number of hydroxyl groups in the crosslinking agent, but it is not limited to this.

[0032] It is understandable that the greater the number of hydroxyl groups in the crosslinking agent, the higher the etching rate of the antireflective layer will be.

[0033] It is also understandable that the greater the number of hydroxyl groups in the crosslinking agent, the more likely the etching rate of the anti-reflective layer will first increase and then decrease, or the etching rate of the anti-reflective layer may first increase and then remain constant, or the etching rate of the anti-reflective layer may first increase and then decrease, and then increase again.

[0034] In other words, the etching rate of the anti-reflective layer is determined not only by the number of hydroxyl groups in the crosslinking agent, but also by the properties of the crosslinking agent itself.

[0035] In other words, the crosslinking agent can be selected according to the actual application, and this application does not impose any specific limitations.

[0036] It should be noted that if the antireflective layer contains only one type of crosslinking agent, the etching rate of the antireflective layer is determined by the mass ratio of the crosslinking agent to the BARC main resin. For example, the higher the mass ratio of the crosslinking agent to the BARC main resin, the more hydroxyl groups are present in the antireflective layer, and the higher the etching rate of the antireflective layer. If the antireflective layer contains multiple types of crosslinking agents, the etching rate of the antireflective layer can be determined by either the mass ratio of the crosslinking agent to the BARC main resin or by the type of crosslinking agent. The specific choice can be made based on the actual application, and this application does not impose any specific limitations.

[0037] It should also be noted that the crosslinking agent can be either a polymeric crosslinking agent or a non-polymeric crosslinking agent. This application preferably uses a polymeric crosslinking agent.

[0038] In some embodiments, the etching rate is 5-8 nm / min, and the mass ratio of the crosslinking agent to the BARC main resin is not less than 0.2 and not greater than 0.6.

[0039] In this embodiment, when the mass ratio of crosslinking agent to BARC main resin is between 0.2 and 0.6, the etching rate of the antireflective coating can reach 5 to 8 nm / min, but it is not limited to this.

[0040] In other words, by changing the mass ratio of the crosslinking agent to the BARC main resin, and by changing the type of crosslinking agent and / or BARC main resin, the etching rate of the anti-reflective coating can be further adjusted. This can be selected according to the actual application, and this application does not make any specific limitations.

[0041] In some embodiments, the crosslinking agent includes one or more of diol crosslinking agents, triol crosslinking agents, tetraol crosslinking agents, pentaol crosslinking agents, and hexaol crosslinking agents.

[0042] It is understood that the anti-reflective coating provided in this application may include one type of crosslinking agent or multiple types of crosslinking agents. In other words, by changing the number of hydroxyl groups in the crosslinking agent in the anti-reflective coating, the etching rate of the anti-reflective coating can be adjusted without significantly changing other properties of the anti-reflective coating.

[0043] In some embodiments, the crosslinking agent is a polyol polymer.

[0044] In this embodiment, the polyol polymer may include one or more of polyethylene glycol and polypropylene glycol.

[0045] The polyethylene glycol may include one or more of polyethylene glycol 400, polyethylene glycol 1000, polyethylene glycol 4000, polyethylene glycol 10000, polypropylene glycol 400, polypropylene glycol 1000, polypropylene glycol 4000, and polypropylene glycol 10000.

[0046] In this embodiment, the number of hydroxyl groups in the crosslinking agent in the antireflective coating is changed by altering the degree of polymerization of the polyol polymer, thereby achieving adjustment of the etching rate of the antireflective coating without significantly changing other properties of the antireflective coating.

[0047] In some embodiments, the degree of polymerization of the polyol polymer can be between 100 and 10,000. For example, 100, 200, 300, 400, 500, 1000, 2000, 4000, 10000, etc. The polyol polymer can be selected according to the actual application, and this application does not make specific limitations.

[0048] In some embodiments, the refractive index of the antireflective layer is 1.75 to 1.85, and the absorbance of the antireflective layer is 0.3 to 0.5.

[0049] Specifically, by changing the number of hydroxyl groups in the crosslinking agent of the antireflective coating, this application can control the refractive index of the antireflective layer between 1.75 and 1.85, and at the same time control the absorbance of the antireflective layer between 0.3 and 0.5. Thus, the etching rate of the antireflective coating can be adjusted without significantly changing other properties of the antireflective coating.

[0050] It should be noted that, in the process of adjusting the etching rate of the antireflective coating by changing the number of hydroxyl groups in the crosslinking agent, this application can control the errors of the refractive index and absorbance of the antireflective coating within a preset range, such as 0.01 to 1. The preset range can be selected according to the actual application of the antireflective coating, and this application does not impose specific limitations on it.

[0051] In some embodiments, the antireflective coating further includes a glycourea derivative, wherein the mass ratio of the glycourea derivative to the BARC main resin is greater than 0 and less than 1. The glycourea derivative may be one or more of aryl-containing glycourea oligomers and tetramethoxymethylglycourea. The mass ratio of the glycourea derivative to the BARC main resin is preferably between 0.4 and 0.6.

[0052] The aryl-containing glycourea oligomer, when prepared into a solution, comprises: the aryl-containing glycourea oligomer and a diluent, wherein the mass concentration of the aryl-containing glycourea oligomer is 33-36%.

[0053] The structural formula of aryl-containing glycourea oligomers can be:

[0054]

[0055] R1 is obtained by coupling an aryl group with 20 or fewer benzene rings to an alkyl group, an alkoxy group, or two glycourea molecules with 20 or fewer carbon atoms. R2 and R3 are hydrogen, an aryl group with 20 or fewer benzene rings, or an alkyl group with 20 or fewer carbon atoms.

[0056] In some embodiments, this application also provides a method for preparing an anti-reflective coating, comprising:

[0057] The methacrylate monomer was polymerized to obtain the BARC main resin;

[0058] The BARC main resin, crosslinking agent, and thermosensitive acid are mixed in a preset ratio to obtain the anti-reflective coating;

[0059] Wherein, the mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1, and the oxygen content of the crosslinking agent determines the etching rate of the antireflective layer; the mass ratio of the thermosensitive acid to the BARC main resin is greater than 0 and less than 1; and the mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100.

[0060] In this embodiment, the solvent includes one or more of propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, or ethyl lactate.

[0061] The crosslinking agent includes one or more of polyethylene glycol 400, polyethylene glycol 1000, polyethylene glycol 4000, polyethylene glycol 10000, polypropylene glycol 400, polypropylene glycol 1000, polypropylene glycol 4000, polypropylene glycol 10000, pentaerythritol tetraglycidyl ether, tetramethoxymethyl glycosuria, hexamethyl melamine, or 2,4,6-tris[bis(methoxymethyl)amino]-1,3,5-triazine.

[0062] Thermosensitive acids include one or more of pyridine p-toluenesulfonate, triethylamine p-toluenesulfonate, trihexylamine p-toluenesulfonate, trioctylamine p-toluenesulfonate, pyridine dodecylbenzenesulfonate, triethylamine dodecylbenzenesulfonate, trihexylamine dodecylbenzenesulfonate, and trioctylamine dodecylbenzenesulfonate.

[0063] The preferred mass ratio of crosslinking agent to BARC main resin is 0.2 to 0.6, the preferred mass ratio of heat-sensitive acid to BARC main resin is 0.05 to 0.15, and the preferred mass ratio of solvent to BARC main resin is 30 to 50.

[0064] This application adjusts the etching rate of the bottom antireflective coating by changing the number of hydroxyl groups in the crosslinking agent, eliminating the need to synthesize BARC main resin to adjust the etching rate of the bottom antireflective coating, thus saving the preparation time of the bottom antireflective coating. At the same time, it also makes the etching performance of the bottom antireflective coating have a wider range of applications and can be used for different etching process conditions.

[0065] In some implementations, the preparation process of the BARC main resin includes:

[0066] The methacrylate monomer and solvent are mixed evenly to obtain a mixture; wherein the mass of the solvent is 4-10 times the mass of the methacrylate monomer, and the mass of the solvent is 10%-20% of the mass of the mixture.

[0067] A catalyst is added to the mixture, and the reaction is carried out for 15-25 hours at a temperature of 60-70°C to obtain a reaction solution; wherein the mass of the catalyst is 1-10 wt% of the mass of the BARC main resin in the reaction solution.

[0068] The reaction solution was cooled and then poured into n-heptane for precipitation. The solution was filtered, the precipitate was collected, and vacuum dried to obtain the BARC main resin.

[0069] The solvent can be one or more of tetrahydrofuran, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, or ethyl lactate, with tetrahydrofuran being the preferred solvent; the catalyst can be one or more of azobisisobutyronitrile, azobisisoheptanenitrile, or dimethyl azobisisobutyrate; and the methacrylate monomer can be one or more of methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and benzyl methacrylate.

[0070] The anti-reflective coating provided in this application will be further described below with reference to specific embodiments.

[0071] Example 1

[0072] An anti-reflective coating with adjustable etching rate is prepared as follows:

[0073] S1. Methyl methacrylate, hydroxyethyl methacrylate and benzyl methacrylate monomers are dissolved in tetrahydrofuran, and then azobisisoheptanenitrile catalyst is added. The mixture is stirred and heated to 66°C for 20 hours. The mass of tetrahydrofuran is 4 times the mass of the monomers, and the mass of azobisisoheptanenitrile is 0.02 times the mass of the monomers.

[0074] S2. Pour the reaction solution from the previous step into n-heptane, stir, precipitate, filter, and dry to obtain the BARC main resin, wherein the mass of n-heptane is 30 times the mass of the monomer.

[0075] S3. Dissolve BARC main resin, polyethylene glycol 400, tetramethoxymethylglycolurea, and triethylamine p-toluenesulfonate in ethyl lactate and stir until completely dissolved to obtain a BARC solution. The mass of tetramethoxymethylglycolurea is 0.5 times that of the main resin, the mass of polyethylene glycol 400 is 0.2 times that of the main resin, the mass of triethylamine p-toluenesulfonate is 0.1 times that of the main resin, and the mass of ethyl lactate is 40 times that of the main resin.

[0076] S4. Using the prepared BARC solution, spin-coat and dry it on the silicon wafer to form a film. Use an ellipsometry to test its refractive index N and absorbance K, and use an etching machine to test its etching rate.

[0077] Example 2

[0078] An anti-reflective coating with adjustable etching rate is prepared as follows:

[0079] S1. Methyl methacrylate, hydroxyethyl methacrylate and benzyl methacrylate monomers are dissolved in tetrahydrofuran, and then azobisisoheptanenitrile catalyst is added. The mixture is stirred and heated to 66°C for 20 hours. The mass of tetrahydrofuran is 4 times the mass of the monomers, and the mass of azobisisoheptanenitrile is 0.02 times the mass of the monomers.

[0080] S2. Pour the reaction solution from the previous step into n-heptane, stir, precipitate, filter, and dry to obtain the BARC main resin, wherein the mass of n-heptane is 30 times the mass of the monomer.

[0081] S3. Dissolve BARC main resin, polyethylene glycol 400, tetramethoxymethylglycolurea, and triethylamine p-toluenesulfonate in ethyl lactate and stir until completely dissolved to obtain a BARC solution. The mass of tetramethoxymethylglycolurea is 0.5 times that of the main resin, the mass of polyethylene glycol 400 is 0.4 times that of the main resin, the mass of triethylamine p-toluenesulfonate is 0.1 times that of the main resin, and the mass of ethyl lactate is 40 times that of the main resin.

[0082] S4. Using the prepared BARC solution, spin-coat and dry it on the silicon wafer to form a film. Use an ellipsometry to test its refractive index N and absorbance K, and use an etching machine to test its etching rate.

[0083] Example 3

[0084] An anti-reflective coating with adjustable etching rate is prepared as follows:

[0085] S1. Methyl methacrylate, hydroxyethyl methacrylate and benzyl methacrylate monomers are dissolved in tetrahydrofuran, and then azobisisoheptanenitrile catalyst is added. The mixture is stirred and heated to 66°C for 20 hours. The mass of tetrahydrofuran is 4 times the mass of the monomers, and the mass of azobisisoheptanenitrile is 0.02 times the mass of the monomers.

[0086] S2. Pour the reaction solution from the previous step into n-heptane, stir, precipitate, filter, and dry to obtain the BARC main resin, wherein the mass of n-heptane is 30 times the mass of the monomer.

[0087] S3. Dissolve BARC main resin, polyethylene glycol 400, tetramethoxymethylglycolic acid and triethylamine p-toluenesulfonate in ethyl lactate and stir until completely dissolved to obtain BARC solution. The mass of tetramethoxymethylglycolic acid is 0.5 times that of the main resin, the mass of polyethylene glycol 400 is 0.6 times that of the main resin, the mass of triethylamine p-toluenesulfonate is 0.1 times that of the main resin, and the mass of ethyl lactate is 40 times that of the main resin.

[0088] S4. Using the prepared BARC solution, spin-coat and dry it on the silicon wafer to form a film. Use an ellipsometry to test its refractive index N and absorbance K, and use an etching machine to test its etching rate.

[0089] Comparative Example 1

[0090] An anti-reflective coating with adjustable etching rate is prepared as follows:

[0091] S1. Methyl methacrylate, hydroxyethyl methacrylate and benzyl methacrylate monomers are dissolved in tetrahydrofuran, and then azobisisoheptanenitrile catalyst is added. The mixture is stirred and heated to 66°C for 20 hours. The mass of tetrahydrofuran is 4 times the mass of the monomers, and the mass of azobisisoheptanenitrile is 0.02 times the mass of the monomers.

[0092] S2. Pour the reaction solution from the previous step into n-heptane, stir, precipitate, filter, and dry to obtain the BARC main resin, wherein the mass of n-heptane is 30 times the mass of the monomer.

[0093] S3. Dissolve the BARC main resin, tetramethoxymethylglyoxal, and triethylamine p-toluenesulfonate in ethyl lactate and stir until completely dissolved to obtain a BARC solution. The mass of tetramethoxymethylglyoxal is 0.5 times that of the main resin, the mass of triethylamine p-toluenesulfonate is 0.1 times that of the main resin, and the mass of ethyl lactate is 40 times that of the main resin.

[0094] S4. Using the prepared BARC solution, spin-coat and dry it on the silicon wafer to form a film. Use an ellipsometry to test its refractive index N and absorbance K, and use an etching machine to test its etching rate.

[0095] The test results of Examples 1-3 and Comparative Example 1 are shown in Table 1:

[0096] Table 1

[0097] Example 1 1.81 0.33 5.65 Example 2 1.82 0.33 6.99 Example 3 1.81 0.32 7.57 Comparative Example 1 1.82 0.33 4.35

[0098] As can be seen from Table 1, this application achieves a higher etching rate by changing the mass ratio of the crosslinking agent to the BARC main resin. At the same time, the changes in the refractive index and absorbance of the antireflective coating are relatively small. This basically verifies that this application can adjust the etching rate of the antireflective coating by changing the oxygen content or hydroxyl content of the crosslinking agent in the antireflective coating, thereby achieving the goal of adjusting the etching rate of the antireflective coating without significantly changing other properties of the antireflective coating.

[0099] This application adds an oxygen-containing macromolecular crosslinking agent to the BARC base resin, which enables the etching rate of the BARC coating to be adjusted by changing the blending ratio. The adjustment range is large, the adjustment ratio is linear, and it does not affect its optical performance. This method can quickly obtain a bottom anti-reflective coating with the required etching rate, so as to be suitable for different etching process conditions and application scenarios.

[0100] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An anti-reflective coating, characterized in that, include: BARC main resin, crosslinking agent, heat-sensitive acid, urea derivatives and solvent; Wherein, the mass ratio of the crosslinking agent to the BARC main resin is greater than 0 and less than 1, and the oxygen content of the crosslinking agent determines the etching rate of the antireflective layer; the mass ratio of the thermosensitive acid to the BARC main resin is greater than 0 and less than 1; the mass ratio of the solvent to the BARC main resin is greater than 0 and less than 100; the BARC main resin is prepared by polymerizing methacrylate monomers. The crosslinking agent comprises a polyol polymer with a degree of polymerization of 100-10000; the mass ratio of the glycourea derivative to the BARC main resin is greater than 0 and less than 1.

2. The anti-reflective coating according to claim 1, characterized in that, The etching rate is 5~8 nm / min, and the mass ratio of the crosslinking agent to the BARC main resin is not less than 0.2 and not greater than 0.

6.

3. The anti-reflective coating according to claim 1, characterized in that, The crosslinking agent also includes one or more of pentaerythritol tetraglycidyl ether, hexahydroxymethyl melamine, or 2,4,6-tris[bis(methoxymethyl)amino]-1,3,5-triazine.

4. The anti-reflective coating according to claim 1, characterized in that, The polyol polymer is one or more of polyethylene glycol and polypropylene glycol.

5. The anti-reflective coating according to claim 4, characterized in that, The polymer includes one or more of polyethylene glycol 400, polyethylene glycol 1000, polyethylene glycol 4000, polyethylene glycol 10000, polypropylene glycol 400, polypropylene glycol 1000, polypropylene glycol 4000, and polypropylene glycol 10000.

6. The anti-reflective coating according to claim 1, characterized in that, The refractive index of the antireflective layer is 1.75~1.85, and the absorbance of the antireflective layer is 0.3~0.

5.

7. A method for preparing an anti-reflective coating, characterized in that, The method for preparing the antireflective coating according to any one of claims 1-6 comprises: The BARC main resin, crosslinking agent, thermosensitive acid, urea derivative and solvent are mixed in a preset ratio to obtain the antireflective coating.

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