Use of polyphosphates as electron beam resist materials

Abstract

The application belongs to the field of photoresist microelectronic chemistry technology, and discloses application of polyphosphate as an electron beam photoresist material, and the structure of the polyphosphate is shown as formula I, wherein R1 is a benzene ring-containing group, R2 is a carbocyclic or heterocyclic group, m is a polymerization degree, 10 <= m <= 1000, and the molecular weight distribution is 1.00-3.0. The polyphosphate is used as the electron beam photoresist material, and has high resolution and high sensitivity, and can be used for manufacturing large-area complex layout.

Description

Technical Field

[0001] This invention belongs to the field of photoresist microelectronic chemistry technology, and relates to the application of polyphosphate as an electron beam photoresist material. Background Technology

[0002] Electron beam lithography, developed in the early 1960s, is a direct patterning technique using electron beams. Due to the extremely short wavelength of electron beams (approximately 0.01-0.007 nm at an accelerating voltage of 15-20 kV) and the fact that the beam diameter after electromagnetic focusing can reach 2 nm, with some areas as fine as 0.1 nm, it can be used to fabricate nanoscale resolution patterns. Currently, electron beam lithography is primarily used to manufacture photomasks. As integrated circuit technology nodes continue to shrink, photomasks for various resolution enhancement technologies are fabricated using electron beam photoresist on electron beam lithography substrates, such as the photomasks required for 193 nm and EUV lithography. The resolution of the electron beam photoresist is a key factor limiting photomask quality; without high-resolution electron beam photoresist, the production of high-end photomasks is impossible.

[0003] Currently, the most commonly used electron beam photoresists in the large-scale integrated circuit industry are polymethyl methacrylate (PMMA) series. Positive electron beam photoresists are one of the classic and universal materials used in electron beam patterning processes. They have high resolution but low sensitivity and require long exposure times. Modified electron beam photoresists, such as the ZEP series photoresists, are prepared using alternating copolymers of α-chloromethyl acrylate and α-methylstyrene. They have a sensitivity one order of magnitude higher than the PMMA series, and their resolution is comparable to that of the PMMA series. However, the stability of the pattern lines after development is slightly worse, and pattern collapse is prone to occur in special scenarios. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing an application of polyphosphate as an electron beam photoresist material, pioneering the application of polyphosphate in the semiconductor processing field. This polyphosphate has the characteristics of high sensitivity and high resolution.

[0005] The technical solution adopted in this invention is as follows:

[0006] An application of a polyphosphate ester as an electron beam photoresist material, wherein the polyphosphate ester has the following structural formula:

[0007]

[0008] The polyphosphate ester is prepared by condensation polymerization of dichlorophosphate and diol, or by ring-opening polymerization of phosphate cyclic monomers. The synthesis method of the polyphosphate ester has been disclosed in Polymer, 2004, 45, 4653-4662, and Biomacromolecules, 2006, 7, 1898-1903.

[0009] The reaction equation and structural formula of the polyphosphate ester are as follows:

[0010]

[0011] Wherein, R1 is a group containing a benzene ring, R2 is a group containing a benzene ring, a carbon ring, or a heterocyclic ring, m is the degree of polymerization, 10≤m≤1000, and the molecular weight distribution is 1.00-3.0.

[0012] Preferably, R1 is at least one of aryl, heteroaryl, aralkyl, heteroarylalkyl, and alkyl; R2 contains at least one of the following groups: aryl, aralkyl, heteroarylalkyl, arenel, heteroarylenel, arynyl, cycloalkenyl, epoxyalkyl, cycloalkyl, cyclic carbonate; or the hydrogen in the above groups is replaced by fluorine, chlorine, or bromine.

[0013] Preferably, R1 is -aryl-alkyl-aryl-, and the alkyl group is a C1-C3 alkyl group;

[0014] R2 is one or more of C6-C10 aryl, C7-C10 aralkyl, C7-C10 heteroarylalkyl, C8-C10 arylenyl, C7-C10 heteroarylenyl, C8-C10 arylynyl, C3-C6 cycloalkenyl, C3-C6 epoxyalkyl, C3-C6 cycloalkyl and five-membered cyclic carbonate groups; preferably, the degree of polymerization of the polyphosphate is 100≤m≤500 and the molecular weight distribution is 1.00-1.50.

[0015] Preferably, the polyphosphate ester has the following structural formula:

[0016]

[0017]

[0018] Structures 1 and 2 contain unsaturated bonds and can be used as negative photoresists, while the other structures can be used as positive photoresists.

[0019] Preferably, the application of polyphosphate as an electron beam photoresist material includes the following steps:

[0020] (1) By weight percentage, 1-15% polyphosphate ester, 0.001-0.1% additives and 84.9-98.999% organic solvent are used to prepare an electron beam photoresist solution;

[0021] (2) Spin-coating the electron beam photoresist solution onto the substrate surface and baking the hard film;

[0022] (3) The photoresist film is subjected to electron beam exposure treatment;

[0023] (4) Develop the pattern using a developer.

[0024] Preferably, the additives include one or more of the following: leveling agents, defoamers, sensitizers, thickeners, plasticizers, dyes, and diluents.

[0025] Preferably, the organic solvent is one or more of water, anisole, propylene glycol monoalkyl ether, toluene, chlorobenzene, benzene, carbon tetrachloride, chloroform, dichloromethane, hexane, propylene glycol alkyl ether acetate, ethyl acetate, butyl acetate, amyl acetate, ethyl lactate, dimethylformamide, cyclopentanone, cyclohexanone, acetone, methyl ethyl ketone, and methyl isobutyl ketone.

[0026] Preferably, the organic solvent is propylene glycol methyl ether acetate, propylene glycol monomethyl ether, amyl acetate, ethyl lactate, or methyl isobutyl ketone.

[0027] Preferably, the baking process in step (2) is controlled at a temperature of 60-150°C, a time of 10-720s, and a photoresist film thickness of 10-500nm.

[0028] Preferably, the voltage of the high-energy electron beam in step (3) is 0.1-300kV, and the exposure dose is ≤300μC / cm. 2 .

[0029] Preferably, when the electron beam photoresist in step (1) is a positive photoresist, the developer in step (4) is a mixture of a good solvent and a bad solvent in a mass ratio of 1:3-9; the good solvent is one or more of propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, amyl acetate, ethyl lactate, cyclopentanone, methyl ethyl ketone, and methyl isobutyl ketone; the bad solvent is isopropanol.

[0030] Preferably, when the electron beam photoresist in step (1) is a negative photoresist, the developer in step (4) is one or more of propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, amyl acetate, ethyl lactate, cyclopentanone, methyl ethyl ketone, and methyl isobutyl ketone.

[0031] The specific development operation in step (4) is as follows: 1) Immerse the substrate in the developing solution for 1-600 seconds; 2) Take out the substrate and immerse it in a poor solvent and shake for 1-600 seconds; 3) Purge with nitrogen to remove residual solvent.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) This invention applies polyphosphate to the semiconductor processing field, giving the material higher added value.

[0034] (2) The polyphosphate of the present invention, as an electron beam photoresist material, has high resolution and high sensitivity, and can be used to fabricate large-area complex patterns. Attached Figure Description

[0035] Figure 1 This is a SEM image of the exposed image from Example 1.

[0036] Figure 2 This is a SEM image after exposure processing in Example 2.

[0037] Figure 3 This is a SEM image of the exposed image from Example 3.

[0038] Figure 4 This is a SEM image of the exposed part from Example 4.

[0039] Figure 5 This is a SEM image of the exposed image from Example 5. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto. For process parameters not specifically noted, conventional techniques can be referred to.

[0041] Synthesis of M-1 to M-5 monomers:

[0042] A phenolic hydroxyl (ol hydroxyl) monomer (50 mmol) was dissolved in 100 mL of dry pyridine, stirred rapidly, and cooled to 0 °C. Then, phosphorus oxychloride (60 mmol) was slowly added dropwise to the reaction system, and stirring continued for 1 hour. After the reaction was complete, 25 mL of ice water was added to quench the reaction, and stirring continued at 0 °C for 1 hour. Finally, the solvent was removed under vacuum, and the residual solid product was suspended in 200 mL of 3 M HCl, filtered, and dried to obtain a solid. The solid was suspended in a saturated sodium bicarbonate aqueous solution, stirred vigorously, filtered, washed three times with purified water, filtered again, the filter cake was washed three times with methanol, filtered, and dried to obtain the monomer.

[0043] The monomer structure is as follows:

[0044]

[0045] Example 1

[0046] Under anhydrous and oxygen-free conditions, bisphenol A (20 mmol) was added to a reaction flask. In an ice-water bath, 50 mL of anhydrous dichloromethane was added and dissolved completely. Triethylamine (44 mmol) was then rapidly added and stirred for 10 minutes. Then, dichlorophosphate (M-1, 20 mmol) dissolved in 10 mL of anhydrous dichloromethane was slowly added dropwise using a constant-pressure dropping funnel over approximately 3 hours. After the addition was complete, the temperature was raised to 40 °C and the reaction was refluxed for 24 hours. After the reaction was complete, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, dissolved in dichloromethane, filtered, and precipitated in diethyl ether. This process of dissolution-filtration-precipitation was repeated three times, followed by vacuum drying to obtain a white powder (polyphosphate). The molecular weight was 42.5 kg / mol, and the molecular weight distribution was 1.18. The glass transition temperature T of this polyphosphate was... g = ~108℃.

[0047] The structure of polyphosphate ester is as follows:

[0048]

[0049] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken for 12 hours at room temperature to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 5 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 2000 rpm and pre-baked at 140 °C for 30 seconds to remove the solvent, resulting in a 100 nm thick film. Finally, the film was subjected to a voltage of 30 kV and a temperature of 200 μC / cm². 2 Electron beam exposure verification was performed at a specific dosage. After exposure, the image was developed in methyl isobutyl ketone for 50 seconds and fixed in isopropanol for 60 seconds to obtain the photoresist pattern. Figure 1 ), with a period of 100nm.

[0050] Example 2

[0051] Under anhydrous and oxygen-free conditions, bisphenol A (10 mmol) was added to a reaction flask. The flask was then placed in an ice-water bath, and 50 mL of anhydrous toluene was added. After complete dissolution, triethylamine (22 mmol) was rapidly added and stirred quickly. After stirring for 10 minutes, dichlorophosphate (M-2, 10 mmol) dissolved in 10 mL of anhydrous toluene was slowly added dropwise using a constant-pressure dropping funnel over approximately 1 hour. After the addition was complete, the temperature was raised to 140 °C, and the reaction was refluxed for 24 hours. After the reaction was complete, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, dissolved in toluene, filtered, and precipitated again in diethyl ether. This process of dissolution-filtration-precipitation was repeated three times, followed by vacuum drying to obtain a white powder (polyphosphate). The molecular weight was 63.1 kg / mol, and the molecular weight distribution was 1.13. The glass transition temperature T of this polyphosphate was... g = ~110℃.

[0052] The structure of polyphosphate ester is as follows:

[0053]

[0054] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken for 12 hours at room temperature to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 3 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 2000 rpm and pre-baked at 100 °C for 60 s to remove the solvent, yielding a 60 nm thick film. Finally, the film was subjected to a voltage of 30 kV and a temperature of 178 μC / cm². 2 At a certain dosage, electron beam exposure was performed for verification. After exposure, the photoresist pattern was developed in methyl isobutyl ketone for 60 seconds and fixed in isopropanol for 60 seconds to obtain the photoresist pattern. Figure 2 Its period is 60nm.

[0055] Example 3

[0056] Under anhydrous and oxygen-free conditions, bisphenol A (20 mmol) was added to a reaction flask. The flask was then placed in an ice-water bath, and 50 mL of anhydrous toluene was added. After complete dissolution, triethylamine (44 mmol) was rapidly added and stirred quickly. After stirring for 10 minutes, dichlorophosphate (M-3, 20 mmol) dissolved in 10 mL of anhydrous toluene was slowly added dropwise using a constant-pressure dropping funnel over approximately 1 hour. After the addition was complete, the temperature was raised to 140 °C, and the reaction was refluxed for 36 hours. After the reaction was complete, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, dissolved in toluene, filtered, and precipitated again in diethyl ether. This process of dissolution-filtration-precipitation was repeated three times, followed by vacuum drying to obtain a white powder (polyphosphate). The molecular weight was 81.2 kg / mol, and the molecular weight distribution was 1.20. The glass transition temperature T of this polyphosphate was...g = ~97℃.

[0057] The structure of polyphosphate ester is as follows:

[0058]

[0059] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken for 12 hours at room temperature to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 3 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 4000 rpm and pre-baked at 90 °C for 5 minutes to remove the solvent, yielding a 50 nm thick film. Finally, the film was subjected to a voltage of 30 kV and a temperature of 150 μC / cm². 2 At a certain dosage, electron beam exposure was performed for verification. After exposure, the photoresist pattern was developed in methyl isobutyl ketone / isopropanol (mass ratio 1:9) for 90 seconds and fixed in isopropanol for 60 seconds to obtain the photoresist pattern. Figure 3 Its period is 80nm.

[0060] Example 4

[0061] Under anhydrous and oxygen-free conditions, bisphenol A (20 mmol) was added to a reaction flask. The flask was then placed in an ice-water bath, and 50 mL of anhydrous toluene was added. After complete dissolution, triethylamine (44 mmol) was rapidly added and stirred quickly. After stirring for 10 minutes, dichlorophosphate (M-4, 20 mmol) dissolved in 10 mL of anhydrous toluene was slowly added dropwise using a constant-pressure dropping funnel over approximately 2 hours. After the addition was complete, the temperature was raised to 140 °C, and the reaction was refluxed for 36 hours. After the reaction was complete, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, dissolved in toluene, filtered, and precipitated again in diethyl ether. This process of dissolution-filtration-precipitation was repeated three times, followed by vacuum drying to obtain a white powder (polyphosphate). The molecular weight was 79.3 kg / mol, and the molecular weight distribution was 1.15. The glass transition temperature T of this polyphosphate was... g = ~89℃.

[0062] The structure of polyphosphate ester is as follows:

[0063]

[0064] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken for 12 hours at room temperature to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 5 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 1000 rpm and pre-baked at 130 °C for 60 s to remove the solvent, yielding a 110 nm thick film. Finally, the film was subjected to a voltage of 30 kV and a temperature of 100 μC / cm².2 At a certain dosage, electron beam exposure was performed for verification. After exposure, the photoresist pattern was developed in methyl isobutyl ketone / isopropanol (mass ratio 2:8) for 60 seconds and fixed in isopropanol for 90 seconds to obtain the photoresist pattern. Figure 4 ), and its lines are 60nm.

[0065] Example 5

[0066] Under anhydrous and oxygen-free conditions, bisphenol A (20 mmol) was added to a reaction flask. The flask was placed in an ice-water bath, and 50 mL of anhydrous dichloromethane was added. After complete dissolution, triethylamine (44 mmol) was rapidly added and stirred quickly. After stirring for 10 minutes, dichlorophosphate (M-4, 20 mmol) dissolved in 10 mL of anhydrous dichloromethane was slowly added dropwise using a constant-pressure dropping funnel over approximately 2 hours. After the addition was complete, the temperature was raised to 40 °C, and the reaction was refluxed for 24 hours. After the reaction was completed, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, and then dissolved in toluene.

[0067] The solution was filtered, precipitated in diethyl ether, and the process of dissolving, filtering, and precipitating was repeated three times. After vacuum drying, a white powder (polyphosphate) was obtained. The molecular weight was 48.5 kg / mol, and the molecular weight distribution was 1.21. The glass transition temperature T of this polyphosphate was... g = ~109℃.

[0068] The structure of polyphosphate ester is as follows:

[0069]

[0070] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken for 12 hours at room temperature to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 3 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 4000 rpm and pre-baked at 120 °C for 60 s to remove the solvent, yielding a 45 nm thick film. Finally, the film was subjected to a voltage of 30 kV and a temperature of 179 μC / cm². 2 At a certain dosage, electron beam exposure verification was performed. After exposure, the image was developed in methyl isobutyl ketone / isopropanol (mass ratio 1:9) for 50 seconds and fixed in isopropanol for 50 seconds to obtain the photoresist pattern. Figure 5 ), its lines are 90nm.

[0071] The lithographic pattern was observed using a scanning electron microscope, revealing that the edges of the independent lines were uniform, with no adhesion, peeling, or delamination, demonstrating good adhesion. Figure 1-5 If phenomena such as peeling, delamination, or line deformation occur, it indicates poor adhesion. Figure 1 The figure shown is Example 1 at 200 μC / cm 2The lithographic pattern with lines / periods of 80nm / 100nm was obtained under the exposure dose. Figure 2 The figure shown is Example 2 at 178 μC / cm 2 The lithographic pattern with lines / periods of 40nm / 60nm was obtained under the exposure dose. Figure 3 The figure shown is Example 3 at 150 μC / cm 2 The lithographic pattern with lines / periods of 50nm / 80nm was obtained under the exposure dose. Figure 4 The figure shown is Example 4 at 100 μC / cm 2 The lithographic pattern obtained under the exposure dose has a line / period of 40nm / 60nm, but there is a bridging defect. Figure 5 The figure shown is from Example 5 at 179 μC / cm 2 The lithographic pattern obtained under the specified exposure dose has a line / period ratio of 72nm / 90nm. The electron beam photoresist provided in this embodiment of the invention exhibits a significant resolution improvement, with a sensitivity of 100-200μC / cm. 2 Under the same conditions, the sensitivity of PMMA is 300-500 μC / cm. 2 .

[0072] Comparative Example 1

[0073] Under anhydrous and oxygen-free conditions, butanediol (20 mmol) was added to a reaction flask, and the mixture was placed in an ice-water bath. 50 mL of anhydrous dichloromethane was added, and after complete dissolution, triethylamine (44 mmol) was rapidly added with stirring. After stirring for 10 minutes, ethyl dichlorophosphate (20 mmol) dissolved in 10 mL of anhydrous dichloromethane was slowly added dropwise using a constant-pressure dropping funnel over approximately 2 hours. After the addition was complete, the temperature was raised to 40 °C, and the reaction was refluxed for 24 hours. After the reaction was complete, the reaction solution was concentrated using a rotary evaporator until a large amount of triethylamine hydrochloride precipitated. The triethylamine hydrochloride was removed by filtration. The filtrate was further concentrated, precipitated in diethyl ether, dissolved in toluene, filtered, and precipitated again in diethyl ether. This process of dissolution-filtration-precipitation was repeated three times, followed by vacuum drying to obtain polyphosphate. The molecular weight was 56.8 kg / mol, and the molecular weight distribution was 1.19.

[0074] The structure of polyphosphate ester is as follows:

[0075]

[0076] Polyphosphate ester, propylene glycol monomethyl ether acetate, and additives were added to a light-proof glass bottle. The mixture was shaken at room temperature for 12 hours to ensure complete dissolution. The solution was then filtered sequentially through 0.5 μm, 0.2 μm, and 0.1 μm filters to obtain a 5 wt% electron beam photoresist solution. This solution was spin-coated onto a silicon wafer at 2000 rpm and pre-baked at 120 °C for 60 seconds to remove the solvent, resulting in a 45 nm thick film. Finally, electron beam exposure was performed for verification, but no photoresist pattern was obtained. This was mainly due to the glass transition temperature (T0) of the polyphosphate ester. g (~-10℃) is too low; at room temperature, the pattern will collapse and cannot maintain its shape.

[0077] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. An application of polyphosphate as an electron beam photoresist material, characterized in that, The structural formula of the polyphosphate ester is as follows: ， Where m is the degree of polymerization, 10 ≤ m ≤ 1000, and the molecular weight distribution is 1.00-3.0; R1 is at least one of aryl, heteroaryl, aralkyl, heteroarylalkyl, and alkyl; R2 contains at least one of the following groups: aryl, aralkyl, heteroarylalkyl, arenel, heteroarylenel, arynyl, cycloalkenyl, epoxyalkyl, cycloalkyl, cyclic carbonate; or the hydrogen in the above groups is replaced by fluorine, chlorine, or bromine.

2. The application according to claim 1, characterized in that, R1 is -aryl-alkyl-aryl-, where the alkyl group is a C1-C3 alkyl group; R2 is one or more of the following: C6-C10 aryl, C7-C10 aralkyl, C7-C10 heteroarylalkyl, C8-C10 arylenyl, C7-C10 heteroarylenyl, C8-C10 aryynyl, C3-C6 cycloalkenyl, C3-C6 epoxyalkyl, C3-C6 cycloalkyl, and five-membered cyclic carbonate group; the polyphosphate ester has a degree of polymerization of 100≤m≤500 and a molecular weight distribution of 1.00-1.

50.

3. The application according to claim 2, characterized in that, The structural formula of the polyphosphate ester is as follows: 。 4. The application according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Prepare an electron beam photoresist solution by weight percentage of 1-15% polyphosphate, 0.001-0.1% additives and 84.9-98.999% organic solvent; (2) Spin-coating the electron beam photoresist solution onto the substrate surface and baking to harden the film; (3) The photoresist film is subjected to electron beam exposure treatment; (4) Develop the pattern using a developing solution.

5. The application according to claim 4, characterized in that, The additives include one or more of the following: leveling agents, defoamers, sensitizers, thickeners, plasticizers, dyes, and diluents; The organic solvent is one or more of the following: water, anisole, propylene glycol monoalkyl ether, toluene, chlorobenzene, benzene, carbon tetrachloride, chloroform, dichloromethane, hexane, propylene glycol alkyl ether acetate, ethyl acetate, butyl acetate, amyl acetate, ethyl lactate, dimethylformamide, cyclopentanone, cyclohexanone, acetone, methyl ethyl ketone, and methyl isobutyl ketone.

6. The application according to claim 5, characterized in that, The organic solvent is propylene glycol methyl ether acetate, propylene glycol monomethyl ether, amyl acetate, ethyl lactate, or methyl isobutyl ketone.

7. The application according to claim 6, characterized in that, The baking temperature in step (2) is controlled at 60-150℃, the time is 10-720s, and the photoresist film thickness is 10-500nm.

8. The application according to claim 7, characterized in that, The voltage of the electron beam in step (3) is 0.1-300kV, and the exposure dose is ≤300μC / cm. 2 .

9. The application according to claim 8, characterized in that, When the electron beam photoresist in step (1) is a positive photoresist, the developer in step (4) is a mixture of a good solvent and a bad solvent in a mass ratio of 1:3-9; the good solvent is one or more of propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, amyl acetate, ethyl lactate, cyclopentanone, methyl ethyl ketone, and methyl isobutyl ketone; the bad solvent is isopropanol. When the electron beam photoresist in step (1) is a negative photoresist, the developer in step (4) is one or more of the following: propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, amyl acetate, ethyl lactate, cyclopentanone, methyl ethyl ketone, and methyl isobutyl ketone.

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