Photoresist composition as well as preparation method and application thereof

Abstract

The invention provides a photoresist composition as well as a preparation method and application thereof. The photoresist composition comprises a solvent; a matrix resin; the tackifier is thiol and a derivative thereof, and the tackifier is used for improving the adhesive force between the photoresist composition and a substrate. According to the photoresist composition disclosed by the invention, the thiol tackifier is added, so that the interaction force between the photoresist composition and the substrate containing the metal surface is enhanced, and the high adhesive force effect of the photoresist composition on the metal film layer is favorably realized.

Description

Technical Field

[0001] The present disclosure relates to the technical field of photoresists, and particularly relates to a photoresist composition, a preparation method thereof, and an application thereof. Background Art

[0002] Since the 1950s, lithography technology has become a basic manufacturing process in the semiconductor industry and is widely used in the development of chips. Photoresist has always been a decisive factor in the progress of lithography technology because the essence of lithography technology is to generate micro-nano patterns through photoresist. Usually, the photoresist is spin-coated to form a film layer with a certain thickness, having a photo-decomposable solubility transition and etching resistance, so it can be quickly used to manufacture nanostructures. The micro-nano patterns of lithography can be transferred to the target substrate through etching. Traditional lithography processes include: wafer pretreatment, film coating, photoresist coating, post-application bake (PAB), exposure, post-exposure bake (PEB), development, etching, and other steps. In the whole lithography process flow, the defects of lithography patterns mainly come from the photoresist coating and development steps.

[0003] In the development process, the exposed area of the photoresist reacts with the developer and dissolves, while the unexposed area does not react with the developer. The lithography pattern is prone to falling off during the whole development process, mainly because the adhesion between the photoresist and the substrate surface is poor, and the isolated photoresist is difficult to adhere to the substrate surface. Therefore, using a tackifier can enhance the adhesion between the photoresist and the wafer substrate and avoid the risk of photoresist pattern peeling or falling off in the subsequent development process.

[0004] In the traditional lithography process, the commercial tackifier hexamethyldisilazane (HMDS) is usually used. Its principle of action is that one end of Si(CH 3 ) 3 in HMDS binds to the wafer substrate, modifying the hydrophilic -OH on the wafer surface to hydrophobic -O-Si(CH 3 ) 3 . Therefore, the non-polar -CH 3 forms a strong interaction with the molecular group composed of C, H, and O in the photoresist, thus achieving good adhesion between the wafer substrate and the photoresist. However, for special semiconductor processes, such as depositing a metal material on the substrate surface to form a metal substrate, the tackifying effect of HMDS on the metal substrate surface is very little. How to improve the interaction force between the photoresist and the metal substrate surface has become one of the problems to be solved in the lithography process.

[0005] The above information disclosed in this part is only used for understanding the background of the inventive concept of the present disclosure. Therefore, the above information may include information that does not constitute the prior art. Summary of the Invention

[0006] In view of this, a first aspect of the present disclosure provides a photoresist composition, comprising: a solvent; a main resin; a tackifier, which is a thiol and its derivatives, and the tackifier is used to improve the adhesion between the photoresist composition and the substrate.

[0007] According to an embodiment of the present disclosure, the tackifier includes one of a monothiol or polythiol containing a straight-chain alkane structure, a poly-monothiol or polythiol containing a branched-chain alkane structure, a monothiol or polythiol containing an aromatic and its derivatives, and a thiol derivative containing a mercapto group.

[0008] According to an embodiment of the present disclosure, the tackifier has a structure shown in Formula I:

[0009] Formula I

[0010] Wherein, n is 1 - 100, and R1 is any one of an alkyl or alkoxy group with 1 - 20 carbon atoms, an ester group with 1 - 20 carbon atoms, a polymer chain with a molecular weight of 2000 - 100000, an aromatic and its derivatives, and an alkane chain containing other heteroatoms.

[0011] According to an embodiment of the present disclosure, the mass percentage of the tackifier in the main resin is 0.1% - 30%.

[0012] According to an embodiment of the present disclosure, the tackifier is selected from at least one of self-thiol, octanethiol, decanethiol, hexadecanethiol, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tetra-3-mercaptopropionate.

[0013] According to an embodiment of the present disclosure, the substrate is a substrate with a metal-containing surface.

[0014] According to an embodiment of the present disclosure, the main resin is selected from at least one of phenolic resin-diazonaphthoquinone type, poly(p-hydroxystyrene) type, polyacrylate type, organic-inorganic hybrid resin type, polycarbonate type, and molecular glass type.

[0015] According to an embodiment of the present disclosure, the solvent is selected from at least one of alcohols, ethers, esters, ketones, alkanes, sulfone organic solvents, amide organic solvents, and aromatic solvents.

[0016] A second aspect of the present disclosure provides a preparation method of the above photoresist composition, comprising:

[0017] S11, preparing the main resin;

[0018] S22, dissolving the main resin in a solvent to obtain a mixed solution;

[0019] S23, adding a tackifier to the mixed solution, dissolving it by shaking and then filtering to obtain the photoresist composition;

[0020] Alternatively,

[0021] S21, prepare the host resin;

[0022] S22, blend the host resin with a tackifier, add a solvent thereto, dissolve by shaking and then filter to obtain a photoresist composition; wherein, the tackifier is thiol and its derivatives, and the tackifier is used to improve the adhesion between the photoresist composition and the substrate.

[0023] The third aspect of the present disclosure provides an application of the above photoresist composition in super-resolution lithography.

[0024] The fourth aspect of the present disclosure provides an application of thiol and its derivatives as a tackifier in a photoresist composition.

[0025] The present disclosure relates to a photoresist composition, a preparation method thereof and an application. By adding a thiol-based tackifier to the photoresist, thiol molecules can be firmly adsorbed on the surfaces of metals such as gold (Au) and silver (Ag) through chemical bonds. This adsorption effect significantly enhances the interfacial adhesion between the substrate with a metal surface and the photoresist, thereby effectively ensuring that the photolithography pattern will not fall off from the substrate with a metal surface during the development process, which is beneficial to improving the pattern quality. Description of the Drawings

[0026] Through the following description of the embodiments of the present disclosure with reference to the drawings, the above and other objects, features and advantages of the present disclosure will become clearer. In the drawings:

[0027] Figure 1 Schematically shows a schematic diagram of the tackifying mechanism of the thiol tackifier according to an embodiment of the present disclosure;

[0028] Figures 2A - 2B Schematically shows a flowchart of the preparation method of the photoresist composition according to an embodiment of the present disclosure;

[0029] Figure 3 Schematically shows a schematic diagram of the test results of the contact angle of the metal film layer and the tackifier according to an embodiment of the present disclosure;

[0030] Figure 4 Schematically shows a flowchart of the process for preparing a photolithography pattern according to an embodiment of the present disclosure;

[0031] Figure 5 Schematically shows the pattern formed by photolithography according to Embodiment 7 of the present disclosure;

[0032] Figure 6 Schematically shows the pattern formed by photolithography according to Embodiment 5 of the present disclosure;

[0033] Figure 7Schematically shows the pattern formed by lithography in Embodiment 9 of the present disclosure;

[0034] Figure 8 Schematically shows the pattern formed by lithography in Comparative Example 1 of the present disclosure;

[0035] Figure 9 Schematically shows the pattern formed by lithography in Comparative Example 2 of the present disclosure.

[0036] It should be noted that, for clarity, in the drawings used to describe the embodiments of the present disclosure, the dimensions of layers, structures, or regions may be enlarged or reduced, that is, these drawings are not drawn to actual scale. Detailed implementation manners

[0037] To make the objectives, technical solutions, and advantages of the present disclosure clearer and more understandable, the present disclosure will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0038] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "including", "comprising", etc. used herein indicate the presence of the described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0039] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0040] In the case of using expressions such as "at least one of A, B, and C, etc.", generally, it should be interpreted according to the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include, but is not limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", generally, it should be interpreted according to the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include, but is not limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0041] In traditional lithography processes, it remains a challenging issue to completely retain the patterned photoresist layer after development and successfully transfer it to the target substrate. Especially in special lithography processes, due to the relatively thin photoresist layer, it is even more difficult to transfer the pattern with high quality. In related technologies, adhesion promoters are added to the photoresist to improve the adhesion between the substrate and the photoresist. However, the existing photoresist adhesion promotion processes have the following problems:

[0042] 1. The traditional commercial adhesion promoter HMDS is mainly used for promoting adhesion to silicon-based materials and has poor adhesion promotion effect on substrates with special metal-containing surfaces.

[0043] 2. During the exposure process, the contact between the photoresist and the developer may cause loss of the photoresist film layer or even film layer peeling off.

[0044] To solve the above problems, the present disclosure proposes a novel adhesion promoter for enhancing the adhesion performance between the photoresist and the substrate with a metal-containing surface, thereby effectively overcoming the deficiencies in the prior art.

[0045] In some embodiments of the present disclosure, a photoresist composition includes: a solvent; a main resin; an adhesion promoter, which is a thiol and its derivatives, and the adhesion promoter is used to improve the adhesion between the photoresist composition and the substrate.

[0046] Referring to Figure 1 , by introducing a mercapto group (-SH), the adhesion promoter can form a thiol-based self-assembled monolayer (SAM) on the surface of the substrate (especially the substrate with a metal-containing surface), thereby significantly enhancing the adhesion between the photoresist and the metal film layer. Specifically, by coating the thiol adhesion promoter on the surface of the substrate with a metal film layer, the mercapto groups adsorbed on the surface of the metal film layer will undergo a deprotonation reaction to form stable metal-sulfur coordination bonds, thereby providing a hydrophobic organic layer on the hydrophilic metal interface. Therefore, when the photoresist composition added with the thiol adhesion promoter is spin-coated onto the substrate containing the metal film layer, a strong interfacial bond can be formed. This chemical bonding interaction can ensure that the photoresist does not peel off from the substrate during the development process, thus ensuring the integrity of the lithography pattern.

[0047] In some embodiments of the present disclosure, the adhesion promoter includes one of a monothiol or polythiol containing a straight-chain alkane structure, a monothiol or polythiol containing a branched-chain alkane structure, a monothiol or polythiol containing an aromatic and its derivatives, and a thiol derivative containing a mercapto group.

[0048] Exemplarily, the adhesion promoter has a structure shown in Formula Ⅰ:

[0049] Formula Ⅰ

[0050] Wherein, n can be 1 - 100, R 1It is any one of an alkyl or alkoxy group with 1 - 20 carbon atoms, an ester group with 1 - 20 carbon atoms, a polymer chain with a molecular weight of 2000 - 100000, an aromatic and its derivatives, and an alkane chain containing other heteroatoms.

[0051] Exemplarily, the alkyl or alkoxy group with 1 - 20 carbon atoms includes methyl (CH 3 -), ethyl (C 2 H 5 -), methoxy (CH 3 O-), ethoxy (C 2 H 5 O-), etc. The ester group with 1 - 20 carbon atoms includes methyl formate (HCOOCH 3 ), ethyl acetate (CH 3 COOC 2 H 5 ), etc. The polymer chain (with a molecular weight of 2000 - 100000) includes polymer chains such as polyethylene and polypropylene. The aromatic and its derivatives include benzene, toluene, phenol, naphthalene, etc. The alkane chain containing other heteroatoms (such as Si) includes methylsiloxane (CH 3 SiO-), etc.

[0052] Theoretically, the tackifier of the present disclosure can be various types of thiols. However, based on comprehensive considerations such as adhesion performance, chemical stability, and process compatibility, the present disclosure preferably includes monothiols or polythiols containing a straight-chain alkane structure and monothiols or polythiols containing a branched-chain alkane structure. These thiols with specific structures have stronger adsorption ability on the metal surface and can form a more stable and uniform self-assembled monolayer (SAM), thereby significantly improving the adhesion between the photoresist and the metal substrate. In addition, their chemical stability in the lithography process and compatibility with the existing process have also been fully verified, and they can effectively meet the requirements of high-precision lithography processes.

[0053] In some embodiments of the present disclosure, the tackifier is selected from at least one of self-thiol, octanethiol, decanethiol, hexadecanethiol, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tetra-3-mercaptopropionate.

[0054] In some embodiments of the present disclosure, the mass percentage of the tackifier in the main resin is 0.1% - 30%. Preferably, the mass percentage of the tackifier in the main resin can be 5% - 20%. More preferably, the mass percentage of the tackifier in the main resin can be 12% - 15%.

[0055] The main function of the adhesion promoter is to improve the adhesion between the photoresist and the substrate with a metal-containing surface. Research shows that the dosage of the adhesion promoter needs to reach a certain proportion to effectively enhance the adhesion performance. Within the range of 0.1% - 30% by mass percentage, the adhesion promoter can form a sufficient self-assembled monolayer (SAM), thereby significantly enhancing the binding force between the photoresist and the substrate with a metal-containing surface. If the dosage of the adhesion promoter is too high, it may cause a decline in other properties of the photoresist (such as photosensitivity, resolution, etc.); if the content of the adhesion promoter is too low, an effective adhesion enhancement effect cannot be achieved. Therefore, within the above mass percentage range, the adhesion promoter can ensure the adhesion performance without having a negative impact on other key properties of the photoresist.

[0056] In some embodiments of the present disclosure, the host resin is selected from at least one of phenolic resin - diazonaphthoquinone type, poly(p-hydroxystyrene) type, polyacrylate type, organic - inorganic hybrid resin type, polycarbonate type, and molecular glass type.

[0057] The adhesion promoter of the present disclosure can be used in combination with various types of photoresists, demonstrating broad applicability and compatibility. For various photoresist systems, this adhesion promoter can effectively improve the adhesion between the photoresist and the substrate with a metal-containing surface, ensuring that the photolithographic pattern is completely retained during the development process and successfully transferred to the target substrate.

[0058] In some embodiments of the present disclosure, the solvent is selected from at least one of alcohols, ethers, esters, ketones, alkanes, sulfone organic solvents, amide organic solvents, and aromatic solvents.

[0059] The adhesion promoter of the present disclosure can also be used in combination with various types of solvents. For various solvents, this adhesion promoter can be uniformly dissolved or dispersed therein without precipitation, delamination, or turbidity, thereby ensuring the stability of the photoresist system. This good solvent compatibility enables the adhesion promoter to exhibit a good adhesion enhancement effect in photoresists with different formulations and can effectively improve the adhesion between the photoresist and the metal substrate.

[0060] Exemplarily, the solvent is selected from any one of propylene glycol methyl ether acetate (PGMEA), n-butyl acetate, ethyl acetate, γ-butyrolactone, propylene glycol methyl ether (PGME), and methyl isobutyl ketone (MIBK).

[0061] Figures 2A - 2B A flowchart schematically showing the preparation method of the photoresist composition according to the above is presented.

[0062] As shown in FIG. 2A, the preparation method of the photoresist composition may include operations S11 - S13.

[0063] In operation S11, a host resin is prepared.

[0064] In operation S12, the main resin is dissolved in a solvent to obtain a mixed solution.

[0065] In operation S13, a tackifier is added to the mixed solution, dissolved by shaking, and then filtered to obtain a photoresist composition.

[0066] Alternatively, as shown in FIG. 2B, the method for preparing the photoresist composition may include operations S21 to S22.

[0067] In operation S21, the main resin is prepared.

[0068] In operation S22, the main resin and the tackifier are blended and then a solvent is added. After dissolving by shaking, the mixture is filtered to obtain a photoresist composition.

[0069] Among them, the tackifier is thiol and its derivatives, and the tackifier is used to improve the adhesion of the photoresist composition to the substrate.

[0070] In the preparation process of the present disclosure, the thiol-based tackifier can be first blended with the main resin, and then a solvent is added; after the composition is fully dispersed and completely dissolved, impurities are removed by filtration, and a photoresist composition that can be used for exposure can be obtained.

[0071] It is also possible to first dissolve the main resin in a solvent, then add the thiol-based tackifier for shaking and dissolving, and finally filter using a filtration device to remove impurities to obtain a photoresist composition.

[0072] In addition, according to different thickness requirements, the concentration of the photoresist composition can be appropriately adjusted to meet specific process requirements.

[0073] The present disclosure also provides an application of the above-mentioned photoresist composition in a special lithography process (such as: super-resolution lithography).

[0074] In some embodiments of the present disclosure, the prepared photoresist composition can be used in a super-resolution lithography process (or called surface plasmon lithography, SP lithography). First, the photoresist composition is spin-coated uniformly on a substrate with a metal surface to ensure the flatness and uniformity of the coating. Subsequently, the coated substrate is pre-treated by baking or the like to remove the solvent and enhance the adhesion of the photoresist to the substrate. After the pre-treatment step, the substrate can be directly used for the exposure process. After the exposure is completed, subsequent process flows such as post-baking and development are carried out in sequence. Finally, a clear and complete lithography pattern can be presented on the substrate, meeting the high-precision requirements of super-resolution lithography.

[0075] The present disclosure also provides an application of thiol and its derivatives as a tackifier in a photoresist composition.

[0076] The novel thiol tackifier of the present disclosure, i.e., the application of thiol as a tackifier for photoresist, is particularly suitable for substrates with metal-containing surfaces. Since the mercapto group (-SH) in the thiol molecule can form stable chemical bonds with substrates having metal surfaces such as silver, this tackifier effectively compensates for the defect of insufficient adhesion performance of traditional commercial tackifiers on substrates with metal-containing surfaces.

[0077] The following further illustrates the present disclosure through specific embodiments. In the following examples, the above-mentioned photoresist composition, its preparation method, and application are specifically described. However, the following examples are only used to illustrate the present disclosure, and the scope of the present disclosure is not limited thereto.

[0078] Examples:

[0079] 1. Host resin 1:

[0080] Dissolve calixarene (3.3 g) in 50 mL of tetrahydrofuran, and then cool the reaction system in an ice bath. Next, slowly add triethylamine (1.616 g) and stir evenly. Then, dissolve 2-diazo-1-phenoxynaphthalene-5-sulfonyl chloride (4.3 g) in 30 mL of tetrahydrofuran within half an hour and add it dropwise to the reaction system through a constant pressure dropping funnel. After the dropping is completed, raise the temperature of the reaction system to 25 °C and continue the reaction at this temperature for 24 hours. After the reaction is completed, pour the reaction mixture into a large amount of water to precipitate the product. Collect the solid product by filtration and wash it with a large amount of water at least 3 times to remove residual reaction reagents and impurities. Then, dry the solid product in a vacuum drying oven for 24 hours. Finally, purify it by column chromatography to obtain the final product, host resin 1. The reaction equation is as follows:

[0081]

[0082] Among them, R 2 is substituted by 2-diazo-1-phenoxynaphthalene-5-sulfonyl chloride, and the grafting ratio of R 2 is 40 - 60%.

[0083] 2. Host resin 2:

[0084] Dissolve phenolic resin (3 g) in 50 mL of dimethylformamide, and then cool the reaction system in an ice bath. Next, slowly add triethylamine (1.5 g) and stir evenly. After that, dissolve 2-diazo-1-phenoxynaphthalene-4-sulfonyl chloride (4 g) in 30 mL of dimethylformamide within half an hour and add it dropwise to the reaction system through a constant-pressure dropping funnel. After the dropping is completed, raise the temperature of the reaction system to 25 °C and continue the reaction at this temperature for 24 hours. After the reaction is completed, pour the reaction mixture into a large amount of water to precipitate the product. Collect the solid product by filtration and wash it with a large amount of water at least 3 times to remove the residual reaction reagents and impurities. Subsequently, dry the solid product in a vacuum drying oven for 24 hours. Finally, purify it by column chromatography to obtain the final product, the main resin 2. The reaction equation is as follows:

[0085]

[0086] Among them, R 3 is substituted by 2-diazo-1-phenoxynaphthalene-4-sulfonyl chloride, and the grafting ratio of R 3 is 20 - 30%.

[0087] 3. Main resin 3:

[0088] Dissolve poly(p-hydroxystyrene) resin (3 g) in 80 mL of dimethylformamide, and then cool the reaction system in an ice bath. Next, slowly add triethylamine (2.5 g) and stir evenly. After that, dissolve 2-diazo-1-phenoxynaphthalene-4-sulfonyl chloride (5 g) in 50 mL of dimethylformamide within half an hour and add it dropwise to the reaction system through a constant-pressure dropping funnel. After the dropping is completed, raise the temperature of the reaction system to 25 °C and continue the reaction at this temperature for 24 hours. After the reaction is completed, pour the reaction mixture into a large amount of water to precipitate the product. Collect the solid product by filtration and wash it with a large amount of water at least 3 times to remove the residual reaction reagents and impurities. Subsequently, dry the solid product in a vacuum drying oven for 24 hours. Finally, purify it by column chromatography to obtain the final product, and then add additive one (PAC) to form the main resin 3. The reaction equation is as follows:

[0089]

[0090] Among them, R 4 is substituted by 2-diazo-1-phenoxynaphthalene-4-sulfonyl chloride, and the grafting ratio of R 4 is 40 - 60%.

[0091] 4. Solvent

[0092] Solvent one: Propylene glycol methyl ether acetate

[0093] Solvent two: n-Butyl acetate

[0094] Solvent Three: Propylene Glycol Methyl Ether

[0095] 5. Other Additives:

[0096] 1) Additive One: PAC Photosensitive Component. The structural formula of PAC is as follows and is specifically a tri-phenol A derivative.

[0097] 。

[0098] Preferably, the mass percentage of the PAC photosensitive component in the main resin can be 10% - 30%.

[0099] 6. Film Layer Preparation and Film Formation Test:

[0100] Take 50 mg of the above-synthesized main resin and dissolve it in 5 mL of solvent. Subsequently, add mercaptan with a mass fraction of 0.1% - 30% relative to the main resin, and shake it well to dissolve, ensuring that the mercaptan is evenly dispersed in the photoresist solution. Then, use a filtration device to filter the mixed solution to remove possible impurities, obtaining a photoresist composition product. Spin-coat the photoresist composition evenly on a substrate with a metal surface, and test the film-forming property and film retention rate of the photoresist film layer. The results are shown in Table 1. In each example, the photoresist compositions added with different mercaptans did not show problems of poor film-forming property or low film retention rate, showing good film layer quality.

[0101] Table 1 Test Results of Photoresist Preparation, Film-Forming Property and Film Retention Rate

[0102]

[0103]

[0104] Note: For the film retention rate, "+" indicates no loss, and "-" indicates loss; for the film-forming property, "+" indicates film formation is possible, and "-" indicates film formation is not possible.

[0105] 7. Comparison of Surface Properties:

[0106] Add trimethylolpropane tris(3-mercaptopropionate) (TMPMP) as a mercaptan tackifier to Main Resin 1 to enhance the interaction between the photoresist and the substrate by forming chemical bonds.

[0107] To reveal its related action mechanism, it was characterized by measuring the water contact angle. As Figure 3 shown, the experimental results show that the water contact angle of the substrate with a metal surface (coated with a silver film layer) is 54°; on the substrate with a metal surface (coated with a silver film layer), after spin-coating HMDS, its water contact angle is 44.5°; after spin-coating TMPMP, its water contact angle is 80.4°.

[0108] In contrast, TMPMP mercaptan significantly modifies the hydrophilic silver surface into a hydrophobic surface. In addition, the chemical bonding between the mercapto group (-SH) in TMPMP and the silver substrate further enhances the adhesion effect, as Figure 3 shown.

[0109] 8. Comparison of the adhesion effect of mercaptans

[0110] Referring to Figure 4 , the prepared photoresist compositions in Examples 1 to 18 were uniformly spin-coated on the surface of a wafer deposited with a metal film layer to prepare a sample substrate. Subsequently, the coated photoresist was baked. After baking, the sample substrate was exposed. After exposure, the substrate was immediately placed on a hot plate at 100 °C for post-baking for 2 minutes. After the sample was naturally cooled to room temperature, it was immersed in a 2.83% standard developer solution of tetramethylammonium hydroxide (TMAH) for 60 seconds. Then, the sample was rinsed with ultrapure water and finally dried with nitrogen to obtain a photolithographic pattern. The test results of the pattern quality are shown in Table 2.

[0111] Table 2 Test results of photoresist formulation and pattern quality

[0112]

[0113]

[0114]

[0115] Comparing the exposure results of the photoresist compositions added with 6 different mercaptan adhesion promoters respectively, all the examples of the present disclosure show a significant adhesion effect. After the complete exposure and development process flows, the photoresist compositions added with mercaptan adhesion promoters do not show peeling off in the pattern area, and the photolithographic patterns are completely preserved. Among them, the exposure test results of Example 7 are as Figure 5 shown, the line grating pattern period is 128 nm, and the pattern in the exposure area is complete; the exposure test results of Example 5 are as Figure 6 shown, the line grating pattern period is 128 nm, and the pattern in the exposure area is complete. The exposure test results of Example 9 are as Figure 7 shown, the line grating pattern period is 128 nm, and the pattern in the exposure area is complete.

[0116] As a comparative experiment, the host resin 1, host resin 2, and host resin 3 were separately dissolved in propylene glycol monomethyl ether acetate (PGMEA) and uniformly spin-coated on the surface of a silver film layer wafer that had been spin-coated with hexamethyldisilazane (HMDS). The spin-coating speed was set at 1000 - 4000 revolutions per minute, and the spin-coating time was 30 seconds. The resulting photoresist film thickness was greater than or equal to 200 nanometers. Subsequently, pre-baking treatment was carried out by baking the wafer at 100 °C for 5 minutes. After the pre-baking was completed, the sample was exposed. After the exposure was completed, the wafer was post-baked at 100 °C for 2 minutes. Finally, the sample was immersed in a 2.83% tetramethylammonium hydroxide (TMAH) developer solution for 60 seconds to complete the development process. The results of the pattern quality test are shown in Table 3:

[0117] Table 3 Results of the comparative experiment

[0118]

[0119] In Comparative Example 1, the pattern area in the exposed area of the photoresist composition significantly peeled off after the exposure and development process, as shown in Figure 8 shown. In Comparative Example 2, the pattern area in the exposed area of the photoresist composition significantly peeled off after the exposure and development process, as shown in Figure 9 shown.

[0120] Based on the above experimental results, it can be clearly concluded that adding thiol-based materials as tackifiers in the photoresist composition of the present disclosure significantly enhances the interaction force between the photoresist and the metal film layer, thereby achieving high adhesion performance of the photoresist to the metal film layer. In contrast, for the photoresist with hexamethyldisilazane (HMDS) added as a tackifier, obvious peeling occurred in the pattern area after the exposure and development process, and the pattern quality was poor.

[0121] In summary, the self-assembly treatment based on thiol can significantly promote the interfacial adhesion between the metal film layer and the photoresist. Thiol-based materials containing hydrophobic chains can achieve stable and reproducible adhesion effects. Thiol molecules can be firmly adsorbed on the surfaces of metals such as gold (Au) and silver (Ag) through chemical bond interactions, thereby ensuring that the photolithography pattern does not peel off from the substrate with a metal surface during the development process, which is beneficial to the improvement of the photolithography quality.

[0122] Those skilled in the art can understand that the features recited in the various embodiments and / or claims of the present disclosure can be combined or / and combined in various ways, even if such combinations or combinations are not explicitly recited in the present disclosure. In particular, without departing from the spirit and teachings of the present disclosure, the features recited in the various embodiments and / or claims of the present disclosure can be combined and / or combined in various ways. All such combinations and / or combinations fall within the scope of the present disclosure.

[0123] Although the present disclosure has been shown and described with reference to specific exemplary embodiments thereof, those skilled in the art should understand that various changes in form and detail may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents. Accordingly, the scope of the present disclosure should not be limited to the above-described embodiments, but should be determined not only by the appended claims but also by the equivalents of the appended claims.

Claims

1. A photoresist composition, characterized in that include: Solvents; Main resin; The adhesion promoter is thiol and its derivatives, and the adhesion promoter is used to improve the adhesion between the photoresist composition and the substrate.

2. The photoresist composition according to claim 1, characterized in that The tackifier includes one of monothiol or polythiol containing a linear alkane structure, monothiol or polythiol containing a branched alkane structure, monothiol or polythiol containing aromatics and their derivatives, and thiol derivatives containing mercapto groups.

3. The photoresist composition according to claim 2, characterized in that The tackifier has a structure as shown in Formula I: Formula I Wherein, n is 1-100, and R1 is any one of an alkyl or alkoxy group having 1-20 carbon atoms, an ester group having 1-20 carbon atoms, a polymer chain having a molecular weight of 2000-100000, an aromatic group and its derivatives, and an alkane chain containing other heteroatoms.

4. The photoresist composition according to claim 1, characterized in that The mass percentage of the tackifier to the main resin is 0.1% to 30%.

5. The photoresist composition according to claim 1, characterized in that The tackifier is at least one selected from hexyl mercaptan, octyl mercaptan, decanethiol, hexadecanethiol, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tetrakis-3-mercaptopropionate.

6. The photoresist composition according to claim 1, characterized in that The substrate is a substrate containing a metal surface.

7. The photoresist composition according to claim 1, characterized in that The main resin is selected from at least one of phenolic resin-diazonaphthoquinone, poly(p-hydroxystyrene), polyacrylate, organic-inorganic hybrid resin, polycarbonate, and molecular glass; the solvent is selected from at least one of alcohol, ether, ester, ketone, alkane, sulfone organic solvent, amide organic solvent, and aromatic hydrocarbon solvent.

8. A method for preparing a photoresist composition according to any one of claims 1 to 7, characterized in that: include: S11, preparing a main resin; S12, dissolving the main resin in a solvent to obtain a mixed solution; S13, adding a thickener to the mixed solution, shaking and dissolving it, and then filtering it to obtain a photoresist composition; or, S21, preparing a main resin; S22, after mixing the main resin and the tackifier, adding a solvent, shaking and dissolving, and filtering to obtain a photoresist composition; wherein the tackifier is thiol and its derivatives, and the tackifier is used to improve the adhesion between the photoresist composition and the substrate.

9. Use of the photoresist composition according to any one of claims 1 to 7 in super-resolution lithography.

10. Use of thiol and its derivatives as adhesion promoters in photoresist compositions.

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