High-resolution photoresist material based on organic-inorganic hybrid resin and preparation method

Abstract

The invention relates to the technical field of photoresist preparation, and particularly discloses a high-resolution photoresist material based on organic-inorganic hybrid resin.The preparation method comprises the steps that firstly, an amino silane coupling agent is adopted for conducting surface treatment on nano-silicon dioxide, amino is introduced to the surface of the nano-silicon dioxide, and then the surface of the nano-silicon dioxide is subjected to surface treatment; the preparation method comprises the following steps: firstly, preparing silicon dioxide, then grafting p-styrene sulfonyl chloride on the surface of the silicon dioxide through the action between amino and an acyl chloride group, and then copolymerizing hydroxyethyl methylacrylate, composite modified silicon dioxide and a tert-butyl acrylate monomer through an addition reaction between double bonds to obtain the film-forming resin. And then adding the film-forming resin, the photoacid generator and the quencher into the organic solvent to obtain the photoresist material, and the photoresist prepared by the invention shows relatively high resolution and good etching resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of photoresist preparation, and particularly relates to a high-resolution photoresist material based on an organic-inorganic hybrid resin and a preparation method thereof. Background Art

[0002] A photoresist is a light-sensitive mixed liquid material, and its core function is to transfer the fine patterns on the mask plate to the surface of the substrate through a photochemical reaction. It is a key material in the manufacturing of semiconductor chips, display panels, and PCBs. A photoresist usually consists of a film-forming resin, a photoinitiator (such as a photoacid generator), a solvent, and other additives. Its working principle is similar to that of a photographic negative: during the exposure process, the photoinitiator absorbs the light energy of a specific wavelength, triggering chemical structure changes (such as crosslinking or decomposition) of the resin, thereby changing the solubility of the photoresist in the developer, and finally forming a micro-nano scale pattern corresponding to the mask plate. According to the development characteristics, photoresists can be divided into positive resists and negative resists. The exposed area of the positive resist dissolves in the developer to form a pattern identical to the mask; the negative resist is the opposite, and the unexposed area is dissolved to form a complementary pattern.

[0003] Among the main components of a photoresist, the film-forming resin is the most important, which determines the dissolution rate, etching resistance, etc. of the photoresist. Acrylate copolymers have the advantages of simple synthesis process, high resolution and sensitivity, and there are many types of acrylate monomers, and suitable monomers can be selected for copolymerization according to various performance requirements of the resin. Therefore, they have great application value in the field of photoresists. However, most of the molecular chains of acrylate polymers show a simple linear structure, resulting in poor plasma etching resistance of acrylates. How to improve the etching resistance of acrylates has become the focus of current research. Chinese patent document CN117756987A discloses an acrylate photoresist film-forming resin and an ArF photoresist and their preparation methods and applications. By carrying out a free radical polymerization reaction of N-substituted maleimide, an acrylate containing an acid-sensitive group, and a polycyclic olefin with a bridging structure, the resulting acrylate photoresist film-forming resin as the film-forming resin of the photoresist can significantly improve the etching resistance, substrate adhesion, sensitivity, and resolution of the photoresist, but its etching resistance still needs to be further improved. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a high-resolution photoresist material based on an organic-inorganic hybrid resin and a preparation method thereof.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A high-resolution photoresist material based on an organic-inorganic hybrid resin, wherein the high-resolution photoresist material includes a film-forming resin, a photoacid generator, a quencher, and an organic solvent.

[0006] In the technical solution disclosed by the present invention, by weight, the amount of the film-forming resin is 10-25 parts, for example, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts can be selected; the amount of the photoacid generator is 2-5 parts, for example, 2 parts, 3 parts, 4 parts, 5 parts can be selected; the amount of the quencher is 0.05-0.1 part, for example, 0.05 part, 0.06 part, 0.07 part, 0.08 part, 0.09 part, 0.1 part can be selected; the amount of the organic solvent is 60-80 parts, for example, 60 parts, 62 parts, 65 parts, 68 parts, 70 parts, 72 parts, 75 parts, 78 parts, 80 parts can be selected. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0007] In the technical solution disclosed by the present invention, the preparation method of the film-forming resin is as follows: S1. Ultrasonically disperse nano-silica in an ethanol aqueous solution, then add an amino-silane coupling agent thereto, stir, filter, wash, and dry to obtain amino-modified nano-silica. S2. Disperse the amino-modified nano-silica in dichloromethane, then add p-styrenesulfonyl chloride and triethylamine thereto, stir and react. After the reaction is completed, filter, wash, dry, and grind to obtain composite-modified silica. S3. Add hydroxyethyl methacrylate, the composite-modified silica, and tert-butyl acrylate to toluene, mix evenly to obtain a mixed solution, cool down to 0-5°C, and then add an initiator to the mixed solution under a nitrogen atmosphere, heat and stir to react. After the reaction is completed, precipitate, dry, and grind to obtain the film-forming resin.

[0008] Specifically, in step S1, the mass ratio of the nano-silica to the amino-silane coupling agent is 10-15:1-3. For example, 10:1, 10:2, 10:3, 12:1, 12:2, 12:3, 15:1, 15:2, 15:3 can be selected. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0009] More specifically, the amino-silane coupling agent is selected from 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, or N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.

[0010] Specifically, in step S2, the mass ratio of the amino-modified nano-silica, p-styrenesulfonyl chloride, and triethylamine is 8-12:4-6:3-5.

[0011] Specifically, in step S2, the stirring reaction is carried out at room temperature, and the time of the stirring reaction is 60 - 120 min. For example, 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, 95 min, 100 min, 105 min, 110 min, 115 min, 120 min can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0012] Specifically, in step S3, the mass ratio of 2 - hydroxyethyl methacrylate, composite modified silica, tert - butyl acrylate and initiator is 15 - 25:5 - 10:10 - 20:1 - 2.

[0013] More specifically, the initiator is selected from benzoyl peroxide or azobisisobutyronitrile.

[0014] Specifically, in step S3, the temperature of the heating and stirring reaction is 60 - 80 °C. For example, 60 °C, 62 °C, 64 °C, 65 °C, 68 °C, 70 °C, 72 °C, 75 °C, 76 °C, 78 °C, 80 °C can be selected; the time of the heating and stirring reaction is 4 - 8 h. For example, 4 h, 4.5 h, 5 h, 5.5 h, 6 h, 6.5 h, 7 h, 7.5 h, 8 h can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0015] In the technical solution disclosed in the present invention, the photoacid generator is selected from diazonium salts, sulfonium salts or iodonium salts. For example, diphenyliodonium perfluoro - 1 - butanesulfonate, triphenylsulfonium chloride, 1 - (2 - naphthoylmethyl) sulfonium trifluoromethanesulfonate, bis(cyclohexylsulfonyl) diazomethane can be selected.

[0016] In the technical solution disclosed in the present invention, the quencher is selected from ethanolamine, diethanolamine, triethanolamine or trihexylamine.

[0017] In the technical solution disclosed in the present invention, the organic solvent is selected from propylene glycol methyl ether acetate, dipropylene glycol methyl ether, amyl acetate or ethyl lactate.

[0018] The present invention also provides a preparation method of the above - mentioned high - resolution photoresist material, including the following steps: adding a film - forming resin, a photoacid generator and a quencher into an organic solvent according to the formula ratio, shaking in the dark to make them fully dissolved, and then filtering to obtain the high - resolution photoresist material.

[0019] Compared with the prior art, the present invention has the following beneficial effects: (1) First, the surface of nano-silica is treated with an amino-silane coupling agent to introduce amino groups onto the surface of the nano-silica. Then, through the reaction between amino groups and acyl chloride groups, p-styrenesulfonyl chloride is grafted onto the surface of the silica. Subsequently, through the addition reaction between double bonds, 2-hydroxyethyl methacrylate, composite modified silica, and tert-butyl acrylate monomer are copolymerized to obtain a film-forming resin. Then, the film-forming resin, photoacid generator, and quencher are added to an organic solvent to obtain a photoresist material. The photoresist prepared by the present invention exhibits high resolution and good etching resistance.

[0020] (2) By grafting p-styrenesulfonyl chloride onto the surface of nano-silica, a double bond structure and a benzene ring structure are introduced onto the surface of the nano-silica. Then, through the polymerization reaction between double bonds, the composite modified silica is introduced into the film-forming resin. The introduction of the silica inorganic material improves the etching resistance of the photoresist. At the same time, the introduction of the rigid benzene ring structure also improves the etching resistance of the photoresist to a certain extent. 2-Hydroxyethyl methacrylate contains a hydroxyl functional group and the composite modified silica contains a sulfonamide group. Introducing them into the film-forming resin effectively improves the adhesion between the film-forming resin and the silicon wafer, thereby improving the resolution of the lithography image. Specific embodiments

[0021] The present invention will be further described in detail below through specific preferred embodiments, but the present invention is not limited to the following embodiments.

[0022] It should be noted that unless otherwise specified, the chemical reagents involved in the present invention are all purchased through commercial channels.

[0023] The average particle size of the nano-silica used in the embodiments of the present invention is 10 nm. Example 1

[0024] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin, comprising the following steps: Add 20 parts of film-forming resin, 4 parts of photoacid generator triphenylsulfonium chloride, and 0.08 part of quencher ethanolamine to 70 parts of propylene glycol monomethyl ether acetate, shake in the dark to dissolve them fully, and then filter using a 0.22-micron filter. The obtained filtrate is the high-resolution photoresist material.

[0025] Among them, the preparation method of the film-forming resin is as follows: S1. Ultrasonically disperse 10 g of nano-silica in 150 mL of 80 wt% ethanol aqueous solution, then add 1 g of 3-aminopropyltriethoxysilane thereto, stir for 2 h, filter, wash, and dry to obtain amino-modified nano-silica; S2. Disperse 8 g of amino-modified nano-silica in 150 mL of dichloromethane, then add 4 g of p-styrenesulfonyl chloride and 3 g of triethylamine thereto, and stir and react at 20 °C for 90 min. After the reaction is completed, filter, wash, dry, and grind to obtain composite-modified silica; S3. Add 15 g of 2-hydroxyethyl methacrylate, 5 g of composite-modified silica, and 10 g of tert-butyl acrylate to 150 mL of toluene, mix evenly to obtain a mixed solution, cool down to 5 °C, and then add 1 g of initiator benzoyl peroxide to the mixed solution under a nitrogen atmosphere, and heat and stir and react at 60 °C for 8 h. After the reaction is completed, drop the reaction solution into deionized water for precipitation, dry, and grind to obtain a film-forming resin. Example 2

[0026] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin, comprising the following steps: Add 10 parts of film-forming resin, 2 parts of photoacid generator bis(cyclohexylsulfonyl) diazomethane, and 0.05 part of quencher ethanolamine to 60 parts of amyl acetate, shake in the dark to dissolve it fully, and then filter it using a 0.22-micron filter. The obtained filtrate is the high-resolution photoresist material.

[0027] Among them, the preparation method of the film-forming resin is as follows: S1. Ultrasonically disperse 15 g of nano-silica in 150 mL of 80 wt% ethanol aqueous solution, then add 3 g of 3-aminopropyltriethoxysilane thereto, stir for 2 h, filter, wash, and dry to obtain amino-modified nano-silica; S2. Disperse 12 g of amino-modified nano-silica in 150 mL of dichloromethane, then add 6 g of p-styrenesulfonyl chloride and 5 g of triethylamine thereto, and stir and react at 20 °C for 90 min. After the reaction is completed, filter, wash, dry, and grind to obtain composite-modified silica; S3. Add 25 g of 2-hydroxyethyl methacrylate, 10 g of composite-modified silica, and 20 g of tert-butyl acrylate to 150 mL of toluene, mix evenly to obtain a mixed solution, cool down to 5 °C, and then add 2 g of initiator benzoyl peroxide to the mixed solution under a nitrogen atmosphere, and heat and stir and react at 80 °C for 4 h. After the reaction is completed, drop the reaction solution into deionized water for precipitation, dry, and grind to obtain a film-forming resin. Example 3

[0028] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin, comprising the following steps: 25 parts of film-forming resin, 5 parts of photoacid generator triphenylsulfonium chloride, and 0.05 part of quencher trihexylamine are added to 80 parts of amyl acetate, and shaken in the dark to dissolve them sufficiently. Then, it is filtered using a 0.22-micron filter, and the resulting filtrate is the high-resolution photoresist material.

[0029] Among them, the preparation method of the film-forming resin is as follows: S1. 12 g of nano-silica is ultrasonically dispersed in 150 mL of 80 wt% ethanol aqueous solution, and then 2 g of 3-aminopropyltriethoxysilane is added thereto, and stirred for 2 h. After filtration, washing, and drying, amino-modified nano-silica is obtained. S2. 10 g of amino-modified nano-silica is dispersed in 150 mL of dichloromethane, and then 5 g of p-styrenesulfonyl chloride and 4 g of triethylamine are added thereto, and stirred at 20 °C for 90 min. After the reaction is completed, it is filtered, washed, dried, and ground to obtain composite-modified silica. S3. 18 g of 2-hydroxyethyl methacrylate, 6 g of composite-modified silica, and 16 g of tert-butyl acrylate are added to 150 mL of toluene, and mixed evenly to obtain a mixed solution. The temperature is lowered to 5 °C, and then 1.5 g of initiator benzoyl peroxide is added to the mixed solution under a nitrogen atmosphere, and heated and stirred at 80 °C for 4 h. After the reaction is completed, the reaction solution is dropped into deionized water for precipitation, dried, and ground to obtain the film-forming resin. Example 4

[0030] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin includes the following steps: 18 parts of film-forming resin, 3 parts of photoacid generator bis(cyclohexylsulfonyl) diazomethane, and 0.06 part of quencher trihexylamine are added to 65 parts of dipropylene glycol methyl ether, and shaken in the dark to dissolve them sufficiently. Then, it is filtered using a 0.22-micron filter, and the resulting filtrate is the high-resolution photoresist material.

[0031] Among them, the preparation method of the film-forming resin is as follows: S1. 10 g of nano-silica is ultrasonically dispersed in 150 mL of 80 wt% ethanol aqueous solution, and then 1 g of 3-aminopropyltriethoxysilane is added thereto, and stirred for 2 h. After filtration, washing, and drying, amino-modified nano-silica is obtained. S2. 10 g of amino-modified nano-silica is dispersed in 150 mL of dichloromethane, and then 5 g of p-styrenesulfonyl chloride and 5 g of triethylamine are added thereto, and stirred at 20 °C for 90 min. After the reaction is completed, it is filtered, washed, dried, and ground to obtain composite-modified silica. S3. Add 24 g of 2-hydroxyethyl methacrylate, 8 g of composite modified silica, and 16 g of tert-butyl acrylate to 150 mL of toluene, mix evenly to obtain a mixed solution, cool it down to 5 °C, and then add 1.5 g of initiator benzoyl peroxide to the mixed solution under a nitrogen atmosphere. Heat and stir the reaction at 70 °C for 6 h. After the reaction is completed, drop the reaction solution into deionized water for precipitation, drying, and grinding to obtain the film-forming resin. Comparative Example 1

[0032] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin includes the following steps: Add 20 parts of film-forming resin, 4 parts of photoacid generator triphenylsulfonium chloride, and 0.08 part of quencher ethanolamine to 70 parts of propylene glycol monomethyl ether acetate, shake in the dark to dissolve it thoroughly, and then filter it using a 0.22-micron filter. The obtained filtrate is the high-resolution photoresist material.

[0033] Among them, the preparation method of the film-forming resin is as follows: Add 15 g of 2-hydroxyethyl methacrylate and 10 g of tert-butyl acrylate to 150 mL of toluene, mix evenly to obtain a mixed solution, cool it down to 5 °C, and then add 1 g of initiator benzoyl peroxide to the mixed solution under a nitrogen atmosphere. Heat and stir the reaction at 60 °C for 8 h. After the reaction is completed, drop the reaction solution into deionized water for precipitation, drying, and grinding to obtain the film-forming resin.

[0034] Compared with Example 1, Comparative Example 1 does not add nano-silica. Comparative Example 2

[0035] A preparation method of a high-resolution photoresist material based on an organic-inorganic hybrid resin includes the following steps: Add 20 parts of film-forming resin, 4 parts of photoacid generator triphenylsulfonium chloride, and 0.08 part of quencher ethanolamine to 70 parts of propylene glycol monomethyl ether acetate, shake in the dark to dissolve it thoroughly, and then filter it using a 0.22-micron filter. The obtained filtrate is the high-resolution photoresist material.

[0036] Among them, the preparation method of the film-forming resin is as follows: S1. Ultrasonically disperse 10 g of nano-silica in 150 mL of 80 wt% ethanol aqueous solution, then add 1 g of vinyltriethoxysilane to it, stir for 2 h, filter, wash, and dry to obtain modified nano-silica; S2. Add 15 g of 2-hydroxyethyl methacrylate, 5 g of modified silica, and 10 g of tert-butyl acrylate to 150 mL of toluene, mix evenly to obtain a mixed solution, cool it down to 5 °C, and then add 1 g of initiator benzoyl peroxide to the mixed solution under a nitrogen atmosphere. Heat and stir the reaction at 60 °C for 8 h. After the reaction is completed, drop the reaction solution into deionized water for precipitation, drying, and grinding to obtain a film-forming resin.

[0037] Compared with Example 1, in Comparative Example 2, vinyltriethoxysilane was used to modify nano-silica.

[0038] Spin coat the photoresist materials prepared in Examples 1-4 and Comparative Examples 1-2 on a silicon wafer treated with hexamethyldisilazane (HMDS), and obtain a photoresist layer with a thickness of 200 nm through baking at 90 °C for 120 s. Use a 193 nm (ArF) lithography machine for exposure, and the exposure dose is 40 mJ / cm 2 , after the exposure is completed, bake on a hot stage at 90 °C for 60 s, develop using an alkaline aqueous developer (2.38 wt% aqueous solution of tetramethylammonium hydroxide), and the development time is 60 s to obtain a preset pattern.

[0039] Lithography accuracy test: Use a scanning electron microscope (SEM) to observe and measure the lithography pattern to obtain the minimum line width that the lithography pattern can separate; the narrower the line width, the higher the lithography accuracy.

[0040] Etch resistance test: Place each polished silicon wafer coated with a photoresist film in an etching machine and etch under the condition of 40 CF4 / 240 Ar / 60 O2 for 30 s. Calculate the etching rate from the film thickness before and after etching and the etching time. The smaller the etching rate, the better the etch resistance.

[0041] Adhesion test: Test the adhesion between the photoresist and the silicon wafer according to the standard of GB / T 9286-2021.

[0042] The test results are shown in Table 1.

[0043]

[0044] As can be seen from Table 1, compared with Comparative Example 1 and Comparative Example 2, the photoresist materials prepared in the examples of the present invention have higher resolution and good etch resistance.

[0045] Finally, it should be noted that: the above embodiments do not limit the present invention in any form. For those skilled in the art, based on the present invention, some modifications and improvements can be made. Therefore, any modification or improvement made without departing from the spirit of the present invention falls within the scope of protection required by the present invention.

Claims

1. A high-resolution photoresist material based on an organic-inorganic hybrid resin, characterized in that: The high-resolution photoresist material comprises a film-forming resin, a photoacid generator, a quencher and an organic solvent; Wherein, the preparation method of the film-forming resin is as follows: S1, ultrasonically dispersing nano-silica in an ethanol aqueous solution, then adding an aminosilane coupling agent thereto, stirring, filtering, washing, and drying to obtain amino-modified nano-silica; S2, dispersing the amino-modified nano-silica in dichloromethane, then adding p-styrenesulfonyl chloride and triethylamine thereto, stirring for reaction, and after the reaction is completed, filtering, washing, drying and grinding to obtain composite modified silica; S3. Add hydroxyethyl methacrylate, composite modified silica and tert-butyl acrylate to toluene, mix well to obtain a mixed solution, cool to 0-5°C, then add an initiator to the mixed solution under a nitrogen atmosphere, heat and stir to react, and after the reaction is completed, precipitate, dry and grind to obtain a film-forming resin.

2. The high-resolution photoresist material according to claim 1, characterized in that: In parts by weight, the film-forming resin is 10-25 parts, the photoacid generator is 2-5 parts, the quencher is 0.05-0.1 parts, and the organic solvent is 60-80 parts.

3. The high-resolution photoresist material according to claim 1, characterized in that: In step S1, the mass ratio of nano-silica to aminosilane coupling agent is 10-15:1-3.

4. The high-resolution photoresist material according to claim 1, characterized in that: In step S2, the mass ratio of amino-modified nano-silica, p-styrenesulfonyl chloride and triethylamine is 8-12:4-6:3-5.

5. The high-resolution photoresist material according to claim 1, characterized in that: In step S3, the mass ratio of hydroxyethyl methacrylate, composite modified silica, tert-butyl acrylate and initiator is 15-25:5-10:10-20:1-2.

6. The high-resolution photoresist material according to claim 1, characterized in that: In step S3, the initiator is selected from benzoyl peroxide or azobisisobutyronitrile.

7. The high-resolution photoresist material according to claim 1, characterized in that: In step S3, the temperature of the heating and stirring reaction is 60-80° C., and the time of the heating and stirring reaction is 4-8 hours.

8. The high-resolution photoresist material according to claim 1, characterized in that: The photoacid generator is selected from diazonium salts, sulfonium salts or iodonium salts, and the quencher is selected from ethanolamine, diethanolamine, triethanolamine or trihexylamine.

9. The high-resolution photoresist material according to claim 1, characterized in that: The organic solvent is selected from propylene glycol methyl ether acetate, dipropylene glycol methyl ether, amyl acetate or ethyl lactate.

10. The method for preparing a high-resolution photoresist material according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: adding film-forming resin, photoacid generator and quencher into organic solvent according to the formula ratio, shaking in the dark to make them fully dissolved, and then filtering to obtain high-resolution photoresist material.

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