Chemical amplification type photoresist and preparation method thereof
By introducing naphthalene-containing photosensitizers and sterically hindered acid diffusion controllers into photoresists, the problem of low exposure window of poly(meth)acrylate resins was solved, and the exposure window of photoresists was improved and the process range was expanded.
Patent Information
- Application Number
- CN202510895443.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-09-16
AI Technical Summary
When poly(meth)acrylate resins are used in chemically amplified photoresists, the exposure window is low, which limits their application.
By introducing a naphthalene-containing photosensitizer and a sterically hindered acid diffusion controller, the acid diffusion process is controlled synergistically to improve the exposure window of the photoresist.
It expands the process adjustment range, reduces the difficulty of product processing, and promotes the application of poly (meth)acrylate resins in chemically amplified photoresists.
Smart Images
Figure CN120652745A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of photoresists, and in particular to a chemically amplified photoresist and a preparation method thereof. Background Art
[0002] Poly(meth)acrylate resins are primarily based on ArF chemically amplified photoresists. Currently, there are few reports on ArF chemically amplified photoresists. With the development of integrated circuits and devices, the resolution requirements for photoresists in large-scale integrated circuits and ultra-large-scale integrated circuits are becoming increasingly higher. Compared to traditional phenolic resin photoresists, I-line chemically amplified photoresists can further improve the resolution of the resin.
[0003] Compared with phenolic resins, poly(meth)acrylate resins have advantages such as low toxicity and good flexibility. However, when used in I-line chemically amplified photoresists, they have the disadvantage of a low exposure window, which limits their application in chemically amplified photoresists. Summary of the Invention
[0004] In order to solve the problem of low exposure window when poly(meth)acrylate resins are used in chemically amplified photoresists in the prior art, the present invention provides a chemically amplified photoresist. The photoresist rationally controls the diffusion distance of acid after exposure through the synergistic effect of resin, photosensitizer, additives and other components, thereby improving the exposure window of the photoresist, thereby solving the problem of low exposure window when poly(meth)acrylate resins are used in chemically amplified photoresists in the prior art.
[0005] The technical solution adopted by the present invention to solve its technical problem is: A chemically amplified photoresist, comprising the following components in parts by weight: 20-40 parts of poly(meth)acrylic acid polymer; Contains 0.1-2 parts of naphthalene-based photosensitizer; 0.1-1 part of steric acid diffusion controller; Leveling agent 0.05-0.2 parts; 60-80 parts of solvent.
[0006] Optionally, the poly(meth)acrylic acid polymer is polymethacrylate or polymethacrylate containing an adamantyl group.
[0007] Optionally, the poly(meth)acrylic acid polymer has a number average molecular weight of 10,000-80,000, and a molecular weight distribution PDI of <2.5.
[0008] Optionally, the naphthyl-containing photosensitizer is selected from at least one of bis(4-hydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene camphorsulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, and (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate.
[0009] Optionally, the hindered acid diffusion controller is at least one selected from tris(3,6-dioxaheptyl)amine, tetrabutylammonium lactate, 4-phenylmorpholine, 2-phenylbenzimidazole, N,N-dimethylaniline, diethanolamine, 1,2-diphenylethylenediamine, and 1,2-cyclohexanediamine.
[0010] Optionally, the leveling agent is selected from at least one of FC 4430 and Troysol S366.
[0011] Optionally, the solvent is propylene glycol methyl ether acetate.
[0012] Another object of the present invention is to provide a method for preparing the chemically amplified photoresist as described above, comprising the following steps: dissolving a poly(meth)acrylic acid polymer, a naphthalene-based photosensitizer, a barrier acid diffusion controller, and a leveling agent in a solvent according to the formula, and stirring and dissolving the mixture to obtain the chemically amplified photoresist.
[0013] The beneficial effects of the present invention are: The chemically amplified photoresist provided by the present invention is based on the characteristics of poly(meth)acrylate polymers. By introducing a naphthalene-containing photosensitizer and a sterically hindered acid diffusion controller, the acid diffusion process is controlled, thereby increasing the exposure window of the photoresist, expanding the process adjustment range, reducing the difficulty of product processing, and promoting the application of poly(meth)acrylate resins in chemically amplified photoresists. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention will be further described below with reference to the accompanying drawings and examples.
[0015] Figure 1 The figures are electron scanning microscope images of the patterns obtained by the photoresists prepared in the embodiments of the present invention and the comparative examples. DETAILED DESCRIPTION
[0016] The present invention will now be described in further detail. The embodiments described below are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.
[0017] Poly(meth)acrylic acid) polymers have a low glass transition temperature. When used in photoresists, the resin chain segments move violently during the post-baking process, and the acid diffusion coefficient increases significantly, which can easily lead to uncontrolled acid diffusion, resulting in a lower exposure window of the photoresist.
[0018] Based on this, in order to solve the problem of low exposure window when poly(meth)acrylate resin is used in chemically amplified photoresist in the prior art, the present invention provides a chemically amplified photoresist. The raw materials of the chemically amplified photoresist include the following components in parts by weight: 20-40 parts of poly(meth)acrylic acid polymer; Contains 0.1-2 parts of naphthalene-based photosensitizer; 0.1-1 part of steric acid diffusion controller; Leveling agent 0.05-0.2 parts; 60-80 parts of solvent.
[0019] The present invention introduces a naphthalene-based photosensitizer into the system, which, on the one hand, improves the photon utilization rate and reduces the lower limit of the exposure dose; on the other hand, it utilizes the steric hindrance of the naphthyl group to reduce the diffusion coefficient of the acid and reduce the line width broadening; at the same time, the rigid structure of the naphthyl group helps to improve thermal stability, increase the pyrolysis temperature, and avoid acid production during pre-baking, thereby improving the exposure window of the photoresist through multiple influences.
[0020] The sterically hindered acid diffusion controller in the present invention refers to a substance that limits acid diffusion through the steric hindrance effect of bulky groups in its molecular structure. The introduction of the sterically hindered acid diffusion controller helps to inhibit lateral acid diffusion, control line width, and reduce acid diffusion distance. Furthermore, by synergistically acting with a naphthalene-containing photosensitizer, the acid diffusion process of poly(meth)acrylate resins when used in chemically amplified photoresists is controlled, thereby improving the exposure window of the photoresist.
[0021] The chemically amplified photoresist provided by the present invention is based on the characteristics of poly(meth)acrylate polymers. By introducing a naphthalene-containing photosensitizer and a sterically hindered acid diffusion controller, the acid diffusion process is controlled, thereby increasing the exposure window of the photoresist, expanding the process adjustment range, reducing the difficulty of product processing, and promoting the application of poly(meth)acrylate resins in chemically amplified photoresists.
[0022] In order to further improve the exposure window of the photoresist, the present invention preferably uses the poly(meth)acrylic acid polymer as polymethacrylate or polymethacrylate containing an adamantyl group; the poly(meth)acrylic acid polymer preferably has a number average molecular weight of 10,000-80,000, a molecular weight distribution PDI <2.5, and more preferably a molecular weight distribution PDI <2.0.
[0023] In the present invention, the preferred naphthyl-containing photosensitizer is selected from at least one of bis(4-hydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene camphorsulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, and (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate; the preferred steric acid diffusion controller is selected from tris(3,6-dioxaheptyl)amine, tetrabutylammonium lactate, 4-phenylmorpholine, 2-phenylbenzimidazole, N,N At least one of dimethylaniline, diethanolamine, 1,2-diphenylethylenediamine, and 1,2-cyclohexanediamine; preferably, the leveling agent is at least one selected from FC 4430 (3M Company) and Troysol S366 (Troy Company); and preferably, the solvent is propylene glycol methyl ether acetate.
[0024] Another object of the present invention is to provide a method for preparing the chemically amplified photoresist as described above, comprising the following steps: dissolving a poly(meth)acrylic acid polymer, a naphthalene-based photosensitizer, a barrier acid diffusion controller, and a leveling agent in a solvent according to the formula, stirring and dissolving the mixture, and filtering the mixture, preferably using a polytetrafluoroethylene microporous membrane filter with a pore size of 0.22 μm, to obtain the chemically amplified photoresist.
[0025] A chemically amplified positive photoresist is prepared by the method for preparing a chemically amplified photoresist provided by the present invention. Based on the characteristics of poly(meth)acrylic acid polymers, the chemically amplified photoresist controls the acid diffusion process by introducing a naphthalene-containing photosensitizer and a sterically hindered acid diffusion controller, thereby increasing the exposure window of the photoresist, expanding the process adjustment range, reducing the difficulty of product processing, and promoting the application of poly(meth)acrylate resins in chemically amplified photoresists.
[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.
[0027] Example 1 This embodiment provides a method for preparing a chemically amplified photoresist, comprising the following steps: Take 20g of commercially available polymethacrylate resin (Mw=55000; PDI=1.07), 1.8g of bis(4-hydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, 0.8g of tri(3,6-dioxaheptyl)amine, 0.05g of FC 4430, and 80g of propylene glycol methyl ether acetate, mix the above ingredients to prepare the glue, filter and package it, and the glue solution that has been ultra-cleaned and packaged is the finished product.
[0028] Examples 2-6 and Comparative Examples 1-2 were prepared in the same manner as in Example 1, and the formulations were shown in Table 1: Table 1 Photolithography test method: The above product was ultrasonically stirred for 1 minute to form a uniform film. After the coating was exposed, it was developed. The thickness of the photoresist coating was 100nm. The developer was a 2.37% aqueous solution of TMAH. The photolithography process conditions were: baking at 120℃ for 5 minutes, and the exposure energy was 33mJ / cm 2 , development time 60s. Photolithography machine: ASMLXT 1900i, optical electron microscope measurement equipment: Hitachi CG4000. Voltage 500V, current setting 6pA.
[0029] The scanning electron microscope images of the patterns obtained from the photoresists prepared in the examples and comparative examples are as follows: Figure 1 shown.
[0030] The exposure windows of the photoresists prepared in various embodiments and comparative examples are shown in Table 2.
[0031] Table 2 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Exposure window (%) 23.6 25.1 26.3 22.8 24.6 23.9 16.5 13.6 As can be seen from the data in Table 2, Examples 1-6 can effectively improve the problem of low exposure window, while Comparative Examples 1 and 2 cannot improve the problem of low exposure window. Specifically, Examples 2-6 are all based on Example 1, mainly changing the type of photosensitizer, the type of acid diffusion controller and the amount used. By adjusting the type and amount of naphthyl-containing photosensitizer and sterically hindered acid diffusion controller, the exposure window of the photoresist pattern of Examples 1-6 is moderate. The above results show that the use of polymethacrylic resin, adjusting its molecular weight and molecular weight distribution, and combining naphthyl-containing photosensitizer and sterically hindered acid diffusion controller can effectively improve the problem of low exposure window. Compared with Example 1, Comparative Examples 1 and 2 use the same naphthalene-containing photosensitizer and hindered acid diffusion controller, and the addition amounts are also the same. Mainly by adjusting the molecular weight and molecular weight distribution of the polymethacrylate resin, the exposure window of the photoresist pattern of Example 1 is moderate, while the exposure windows of the photoresist patterns of Comparative Examples 1 and 2 are both low.
[0032] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.
Claims
1. A chemically amplified photoresist, characterized in that: The raw materials include the following components in parts by weight: 20-40 parts of poly(meth)acrylic acid polymer; Contains 0.1-2 parts of naphthalene-based photosensitizer; 0.1-1 part of steric acid diffusion controller; Leveling agent 0.05-0.2 parts; 60-80 parts of solvent.
2. The chemically amplified photoresist according to claim 1, wherein The poly(meth)acrylic acid polymer is polymethacrylate or polymethacrylate containing an adamantyl group.
3. The chemically amplified photoresist according to claim 1, wherein The number average molecular weight of the poly(meth)acrylic acid polymer is 10,000-80,000, and the molecular weight distribution PDI is less than 2.
5.
4. The chemically amplified photoresist according to claim 1, wherein The naphthyl-containing photosensitizer is selected from at least one of bis(4-hydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, (4,7-dibutoxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene camphorsulfonate, (4,7-dihydroxy-1-naphthyl)dimethylsulfonium trifluoromethanesulfonate, (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene nonafluorobutanesulfonate, and (4,7-dihydroxy-1-naphthyl)tetrahydrothiophene trifluoromethanesulfonate.
5. The chemically amplified photoresist according to claim 1, wherein The sterically hindered acid diffusion controller is at least one selected from tris(3,6-dioxaheptyl)amine, tetrabutylammonium lactate, 4-phenylmorpholine, 2-phenylbenzimidazole, N,N-dimethylaniline, diethanolamine, 1,2-diphenylethylenediamine, and 1,2-cyclohexanediamine.
6. The chemically amplified photoresist according to claim 1, wherein The leveling agent is selected from at least one of FC 4430 and Troysol S366.
7. The chemically amplified photoresist according to claim 1, wherein The solvent is propylene glycol methyl ether acetate.
8. A method for preparing a chemically amplified photoresist according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: dissolving poly(methyl)acrylic acid polymer, naphthalene-based photosensitizer, acid diffusion control agent and leveling agent in a solvent according to the formula, stirring and dissolving the mixture to obtain a chemically amplified photoresist.