Organic micromolecule eutectic crystal photoresist, preparation method thereof and application of photoresist in near ultraviolet lithography

Abstract

The invention discloses a small organic molecule eutectic crystal photoresist, a preparation method thereof and application of the small organic molecule eutectic crystal photoresist in near ultraviolet photoetching. The small organic molecule eutectic crystal photoresist disclosed by the invention is obtained by co-assembling 9, 10-anthracene dicarboxylic acid and amine small molecules; the co-assembly is realized through intermolecular hydrogen bonds and electrostatic interaction combination; the amine small molecules are selected from at least one of morpholine, thiomorpholine, triethylamine, triethanolamine and methyl piperazine. The small organic molecule eutectic crystal photoresist disclosed by the invention can be used for forming a forward photoetching structure through photo-induced molecular cascade decarboxylation and oxidation reaction in an absorbable low-energy ultraviolet wavelength range. The organic micromolecule eutectic crystal photoresist has the advantages of simple preparation process, high photoetching efficiency, high controllability of a three-dimensional structure and the like, and has a wide application prospect in the field of micro-nano processing.

Description

Technical Field

[0001] The present invention belongs to the field of photoresists, and relates to an organic small molecule eutectic crystal photoresist, a preparation method thereof, and an application in low-energy near-ultraviolet lithography. Background Art

[0002] Lithography is a process that uses light to transfer a pattern from a mask to a substrate through a photosensitive resist (photoresist). This technology plays a crucial role in the field of semiconductor manufacturing. During the lithography process, the photoresist plays a core role. Its working principle is as follows: Light passes through the mask and irradiates the surface of the substrate covered with the photoresist (such as a silicon wafer), causing a chemical reaction in the irradiated area of the photoresist, changing its molecular polarity, and thus affecting its solubility in the developer. Positive photoresists will remove the pattern corresponding to the light-transmitting area of the mask after development. The photochemical reactions of positive photoresists usually involve processes such as the degradation of polymer chains, the deprotection of functional groups, rearrangement, or intramolecular dehydration, while negative photoresists are based on crosslinking reactions between polymer chains.

[0003] The type of photoresist, preparation technology, and compatibility with lithography equipment are key factors determining the accuracy of lithography patterns. For lithography technology pursuing high precision, the uniformity of the photoresist layer and photochemical properties (such as the light reaction efficiency and the difference in solubility in the developer) have a significant impact on the accuracy of lithography patterns and the line edge roughness, and thus determine the size and density of components in microelectronic chips. Traditional photoresists are mainly made of polymer materials due to their good film-forming properties and adhesion to the substrate. According to the reaction mechanism, these photoresists can be divided into three categories: photocrosslinking type, such as polyvinyl cinnamate, which forms an insoluble network structure under ultraviolet light; photodecomposition type, such as poly(p-hydroxystyrene), which decomposes under the action of acid; and photobroken chain type, such as polycarbonate, which decomposes under extreme ultraviolet light to produce low molecular weight fragments. These photoresists are widely used in the semiconductor industry due to their high resolution, sensitivity, and efficiency.

[0004] Compared with polymer photoresists, the development of small molecule crystalline photoresists lags behind. Theoretically, small molecule crystal photoresists have advantages such as a clear molecular structure, high batch-to-batch repeatability, strong plasticity, high mobility of photochemical reaction products, and few by-products. However, problems such as insufficient film-forming properties and uneven coverage thickness of small molecule crystal photoresists limit their application and development.

[0005] Topochemical reaction is a potential method to solve these problems. Topochemical reaction refers to a solid-state reaction that occurs under the strict control of the molecular arrangement in the crystal lattice. Through molecular pre-arrangement, small molecule crystals can form highly ordered structures, which not only improve the selectivity of the reaction but also make the reaction threshold more definite. Moreover, the surface of the small molecule crystal photoresist has good reaction isotropy, enabling more precise and uniform reactions. These characteristics can significantly improve the resolution of the photoresist, promote the development of projection three-dimensional rapid lithography technology, and are expected to provide a new technical path for high-precision micro-nano manufacturing. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] An organic small molecule co-crystal photoresist, wherein the organic small molecule co-crystal photoresist is obtained by co-assembling 9,10-anthracenedicarboxylic acid and amine small molecules; the co-assembly is achieved through a combination of intermolecular hydrogen bonds and electrostatic interactions.

[0008] According to an embodiment of the present invention, the amine small molecules are selected from at least one of morpholine, thiomorpholine, triethylamine, triethanolamine, and methylpiperazine.

[0009] According to an embodiment of the present invention, the surface of the crystal of the organic small molecule co-crystal photoresist is flat.

[0010] According to an embodiment of the present invention, the crystal of the organic small molecule co-crystal photoresist has a regular three-dimensional structure. Preferably, the length, width, and height of the regular three-dimensional structure are all not greater than 200 μm, for example, independently selected from 10 - 100 μm, 50 - 100 μm, and 100 - 200 μm.

[0011] Exemplarily, the crystal of the organic small molecule co-crystal photoresist has a regular three-dimensional rhombic block shape, with a length of 100 - 200 μm, a width of 100 - 200 μm, and a height of 50 - 100 μm.

[0012] Exemplarily, the crystal of the organic small molecule co-crystal photoresist has a regular cubic shape, with a length of 10 - 50 μm, a width of 10 - 50 μm, and a height of 10 - 100 μm.

[0013] According to an embodiment of the present invention, the organic small molecule co-crystal photoresist can undergo decarboxylation and / or oxidation reactions under the irradiation of near-ultraviolet light.

[0014] According to an embodiment of the present invention, the organic small molecule co-crystal photoresist has positive photolithography performance.

[0015] The present invention also provides a method for preparing the above-mentioned small molecule co-crystal crystal photoresist, which specifically includes the following steps:

[0016] (1) Dissolve 9,10-anthracenedicarboxylic acid in a solvent to obtain a monomer solution of 9,10-anthracenedicarboxylic acid; that is, dissolve an amine small molecule in a solvent to obtain a monomer solution of the amine small molecule;

[0017] (2) Mix the monomer solution of 9,10-anthracenedicarboxylic acid obtained in step (1) with the monomer solution of the amine small molecule. After co-assembly of 9,10-anthracenedicarboxylic acid and the amine small molecule, age to obtain the small molecule co-crystal crystal photoresist.

[0018] According to an embodiment of the present invention, in the monomer solution of 9,10-anthracenedicarboxylic acid, the concentration of 9,10-anthracenedicarboxylic acid is 0.1 to 1 mg / mL, for example, 0.5 mg / mL.

[0019] According to an embodiment of the present invention, the concentration of the monomer solution of the amine small molecule is 0.1 to 10 μL / mL, for example, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL.

[0020] According to an embodiment of the present invention, in step (1), the solvents in the monomer solution of 9,10-anthracenedicarboxylic acid and the monomer solution of the amine small molecule can be the same or different, and are independently selected from one of acetone, tetrahydrofuran, and ethanol.

[0021] According to an embodiment of the present invention, in step (2), when mixing, the volume ratio of the monomer solution of anthracenedicarboxylic acid to the monomer solution of the amine small molecule is 1:1 to 10:1, for example, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1.

[0022] According to an embodiment of the present invention, the co-assembly refers to the intermolecular hydrogen bonding and / or electrostatic interaction between 9,10-anthracenedicarboxylic acid and the amine small molecule.

[0023] According to an embodiment of the present invention, the aging refers to standing under the condition of above 30 °C (such as 35 °C).

[0024] According to an embodiment of the present invention, after aging, the small molecule co-crystal crystal photoresist can also be cleaned by a method known in the art.

[0025] The present invention also provides the application of the above-mentioned small molecule co-crystal crystal photoresist in the fields of microelectronics and semiconductor manufacturing, micro-nano processing or lithography, such as for rapid in-situ lithography or three-dimensional lithography.

[0026] The present invention also provides a method for in-situ lithography, which includes: performing lithography on the organic small molecule co-crystal crystal photoresist under light illumination conditions to obtain a target pattern;

[0027] The organic small molecule co-crystal crystal photoresist can be contacted with a developer before light illumination, or the organic small molecule co-crystal crystal photoresist can be contacted with the developer after lithography.

[0028] According to an embodiment of the present invention, the developer is selected from at least two or more organic solvents. Preferably, the organic solvent is selected from one or more of methanol, ethanol, acetone, tetrahydrofuran, dichloromethane, and chloroform. Preferably, the developer includes two different organic solvents, and the volume ratio thereof can be 1:1 to 1:20.

[0029] According to a preferred embodiment of the present invention, before light illumination, the organic small molecule co-crystal crystal photoresist is placed in the developer, and the small molecule co-crystal crystal photoresist is deposited on the two-dimensional substrate. Before light illumination, the organic small molecule co-crystal crystal photoresist is contacted with the developer, and then lithography is performed.

[0030] According to an embodiment of the present invention, the two-dimensional substrate is selected from at least one of a glass sheet, a quartz sheet, a silicon wafer, a mica sheet, and graphite.

[0031] According to an embodiment of the present invention, the light illumination conditions are specifically a near-ultraviolet light excitation source, which can be any one of a laser, an LED light, and a mercury lamp, for example.

[0032] According to an embodiment of the present invention, the wavelength of the near-ultraviolet light excitation source is selected within the absorption wavelength range of the organic small molecule co-crystal crystal photoresist.

[0033] According to an embodiment of the present invention, the power of the near-ultraviolet light excitation source is 0.1 - 30 mW, such as 0.1 - 10 mW, or for example 1 mW and 5 mW.

[0034] According to an embodiment of the present invention, during lithography, the exposure area range of the light illumination is controlled. The organic small molecule co-crystal crystal photoresist located in the exposure area reacts to obtain a light illumination product, and the light illumination product is directly dissolved in the developer, while the organic small molecule co-crystal crystal photoresist located in the non-exposure area remains, achieving a rapid in-situ positive lithography effect.

[0035] According to an embodiment of the present invention, the lithography depth of the organic small molecule co-crystal crystal photoresist has a linear relationship with the cumulative exposure time of the exposure area. Exemplarily, the cumulative exposure time of the exposure area can be specifically selected according to the needs of the target pattern, such as 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, 70 seconds, 80 seconds, 90 seconds, and 100 seconds.

[0036] According to an embodiment of the present invention, the lithography depth of the organic small molecule co-crystal crystal photoresist has a linear relationship with the exposure intensity of the exposure area.

[0037] The present invention also provides a three-dimensional positive lithography method, which includes: immersing the above-mentioned organic small molecule co-crystal crystal photoresist in a developer, and adjusting the exposure amount at different spatial positions in the exposure area (such as adjusting the exposure intensity and / or exposure cumulative time) under light illumination conditions to obtain an in-situ three-dimensional positive lithography structure.

[0038] According to an embodiment of the present invention, the pattern of the in-situ three-dimensional positive lithography structure can be selected from three-dimensional structures known in the art, and the present invention does not make specific limitations.

[0039] According to an embodiment of the present invention, the exposure area can be set according to the pattern of the in-situ three-dimensional positive lithography structure, and the present invention does not make specific limitations.

[0040] According to an embodiment of the present invention, during lithography, the organic small molecule co-crystal crystal photoresist located in the exposure area undergoes a reaction to obtain a light-exposed product, and the light-exposed product is directly dissolved in the developer, while the organic small molecule co-crystal crystal photoresist located in the non-exposure area remains, achieving a rapid in-situ positive lithography effect.

[0041] According to an embodiment of the present invention, the lithography depth of the organic small molecule co-crystal crystal photoresist has a linear relationship with the exposure cumulative time of the exposure area. Exemplarily, the exposure cumulative time of the exposure area can be specifically selected according to the needs of the target pattern, such as 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, 70 seconds, 80 seconds, 90 seconds, 100 seconds.

[0042] According to an embodiment of the present invention, the lithography depth of the organic small molecule co-crystal crystal photoresist has a linear relationship with the exposure intensity of the exposure area. According to an embodiment of the present invention, the power of the near-ultraviolet light excitation light source is 0.1 - 30 mW, such as 0.1 - 10 mW, and for another example, it is 1 mW, 5 mW.

[0043] Beneficial effects

[0044] The present invention uses co-assembly of anthracenedicarboxylic acid and amine small molecules to prepare a small molecule co-crystal crystal photoresist with a flat surface. These small molecule co-crystal crystal photoresists undergo cascade decarboxylation and oxidation reactions under the irradiation of low-energy ultraviolet light. There is a huge difference in molecular polarity before and after the reaction, and a positive lithography structure pattern is obtained by selectively dissolving the exposed area with a developer.

[0045] The present invention utilizes the linear correlation between the light intensity in the exposed area and the lithography depth, and by controlling the light intensity at different spatial positions of the lithography pattern, a three-dimensional positive lithography structure is rapidly and directly obtained, realizing direct three-dimensional lithography at the minute level. This technological advancement can effectively reduce the energy consumption of the light source while significantly improving the production efficiency of the lithography process, and has great application value in the fields of microelectronics and semiconductor manufacturing. The organic small molecule crystal photoresist of the present invention has the advantages of simple preparation process, high lithography efficiency, strong controllability of three-dimensional structure, etc., and has broad application prospects in the field of micro-nano processing. Description of the Drawings

[0046] Figure 1 . Optical microscope image of the organic small molecule co-crystal photoresist 1 in Example 1 of the present invention.

[0047] Figure 2 . Scanning electron microscope image of the organic small molecule co-crystal photoresist 1 in Example 1 of the present invention.

[0048] Figure 3 . UV-visible absorption spectrum of the organic small molecule co-crystal photoresist 1 in Example 1 of the present invention.

[0049] Figure 4 . NMR data spectrum of the organic small molecule co-crystal photoresist 1 in Example 1 of the present invention.

[0050] Figure 5 . NMR hydrogen spectrum data of the organic small molecule co-crystal photoresist 1 in Example 1 of the present invention after being ground and evenly coated on a glass slide and irradiated with ultraviolet light at 405 nm for different times in an oxygen environment.

[0051] Figure 6 . Scanning electron microscope image of the small molecule co-crystal photoresist 1 in Example 2 of the present invention after being irradiated by a linear 405-nm laser light source and rinsed with a developer (the lithography excitation light powers from left to right are 0.177, 0.225, 0.261, and 0.319 mW respectively).

[0052] Figure 7 . Relationship diagram of the change in the positive lithography depth obtained after the organic small molecule co-crystal photoresist 1 in Example 2 of the present invention is irradiated by 405-nm laser light sources with different intensities and rinsed with a developer.

[0053] Figure 8 . Two-dimensional digital light processing projection pattern projected by program setting in Example 3 of the present invention.

[0054] Figure 9Scanning electron microscope image (Figure a) and atomic force microscope image (Figure b) of the three-dimensional structure obtained after lithography of the small molecule co-crystal crystal photoresist 1 in Example 3 of the present invention by two-dimensional digital light processing projection pattern lithography with a 385-nanometer ultraviolet light source.

[0055] Figure 10 Scanning electron microscope image of the organic small molecule co-crystal crystal photoresist 2 in Example 4 of the present invention.

[0056] Figure 11 Ultraviolet-visible absorption spectrum of the organic small molecule co-crystal crystal photoresist 2 in Example 4 of the present invention.

[0057] Figure 12 Nuclear magnetic data spectrum of the organic small molecule co-crystal crystal photoresist 2 in Example 4 of the present invention.

[0058] Figure 13 1H NMR data spectrum after the organic small molecule co-crystal crystal photoresist 2 in Example 4 of the present invention was ground and evenly coated on a glass slide and irradiated with ultraviolet light at 405 nanometers for different times in an oxygen environment.

[0059] Figure 14 Two-dimensional digital projection light pattern (wavelength: 385 nanometers) projected by program setting in Example 5 of the present invention.

[0060] Figure 15 Scanning electron microscope image of the positive three-dimensional structure obtained after lithography of the small molecule co-crystal crystal photoresist 2 in Example 5 of the present invention with a two-dimensional digital projection light pattern of a 385-nanometer light source. Detailed Description of the Invention

[0061] The technical solutions of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only illustrative of and explanatory of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0062] Unless otherwise specified, the raw materials and reagents used in the following examples are all commercially available products or can be prepared by known methods.

[0063] Example 1

[0064] Prepare a small molecule co-crystal crystal photoresist 1 formed by co-assembly of 9,10-anthracenedicarboxylic acid molecules and thiomorpholine. The preparation method is as follows:

[0065] (1) Dissolve 15 mg of the powder of 9,10-anthracenedicarboxylic acid molecular solid in 75 mL of acetone to obtain a 9,10-anthracenedicarboxylic acid monomer solution with a concentration of 0.96 mmol / L. Dissolve 7.1 μL of thiomorpholine liquid completely in 25 mL of acetone to obtain a thiomorpholine solution with a concentration of 2.56 mmol / L.

[0066] (2) Mix 75 mL of the 9,10-anthracenedicarboxylic acid monomer solution (0.96 mmol / L) in step (1) with a thiomorpholine acetone solution (2.56 mmol / L) with a volume ratio of 3:1. Let it stand at an ambient temperature of 35 °C for 12 hours to prepare a photoresist containing organic small molecule co-crystals at the bottom of the solution. This organic small molecule co-crystal is co-assembled through hydrogen bonds and electrostatic interactions between 9,10-anthracenedicarboxylic acid and thiomorpholine molecules.

[0067] Disperse the photoresist 1 containing organic small molecule co-crystals obtained in step (2) in n-hexane and wash and filter it three times repeatedly to obtain the organic small molecule co-crystal photoresist 1 after removing surface impurities. The optical microscope and scanning electron microscope characterizations of the morphology of the organic small molecule co-crystals in the photoresist are as Figure 1 and Figure 2 shown. As can be seen from Figure 1 , the crystal shape of the organic small molecule co-crystal photoresist 1 prepared in this example is a regular three-dimensional rhombic block, with a length of 100 - 200 μm, a width of 100 - 200 μm, and a height of 50 - 100 μm. As can be seen from Figure 2 , the crystal of the organic small molecule co-crystal photoresist 1 prepared in this example has a flat surface.

[0068] Test Example 1

[0069] Use the Lambda 1050+ ultraviolet-visible spectrophotometer to test the effective ultraviolet-visible absorption spectrum range of the organic small molecule co-crystal photoresist 1 obtained by the preparation method of Example 1. The results are as Figure 3 shown. It can be seen that the ultraviolet-visible light absorption range of the organic small molecule co-crystal photoresist 1 covers the wavelength range of 300 - 430 nm.

[0070] Test Example 2

[0071] Perform nuclear magnetic resonance hydrogen spectrum analysis on the chemical composition of the organic small molecule co-crystal photoresist 1 obtained by the preparation method of Example 1: Dissolve the organic small molecule co-crystal photoresist 1 in deuterated dimethyl sulfoxide, and obtain the nuclear magnetic spectrum through nuclear magnetic resonance analysis as Figure 4As shown, through the analysis of the chemical shift peak positions and integral information, it can be known that the molar ratio of 9,10-anthracenedicarboxylic acid molecules to thiomorpholine molecules in the organic small molecule co-crystal crystal photoresist 1 is 1:1.

[0072] Test Example 3

[0073] The organic small molecule co-crystal crystal photoresist 1 obtained by the preparation method of Example 1 was subjected to analysis of the photoreaction products:

[0074] Take 10 mg of the organic small molecule co-crystal crystal photoresist 1 and evenly coat it on a glass slide. Under an oxygen environment, irradiate it with 405 nm LED light (light intensity: 325 mW), and remix it once every minute of irradiation. Samples are taken after 0 minutes, 3 minutes, 6 minutes, 9 minutes, and 14 minutes of irradiation respectively. The test samples at different time points and the anthraquinone sample (blank reference sample) are respectively dissolved in deuterated dimethyl sulfoxide for nuclear magnetic resonance hydrogen spectrum analysis. The nuclear magnetic data spectra are as Figure 5 shown.

[0075] As Figure 5 can be seen, with the increase of the irradiation time, the generated anthraquinone in different test samples gradually increases, indicating that the organic small molecule co-crystal crystal photoresist 1 generates the oxidation product anthraquinone under the irradiation of near-ultraviolet light within the absorption range.

[0076] In order to further verify the generation mechanism of anthraquinone, a deoxygenation control experiment was carried out: under an anaerobic environment, the organic small molecule co-crystal crystal photoresist 1 was irradiated under the same conditions, and the control samples after 0 minutes, 3 minutes, 6 minutes, 9 minutes, and 14 minutes of irradiation were taken respectively. No generation of anthraquinone was detected in the control samples under anaerobic conditions. It can be seen from this that the generation of anthraquinone in the photoreaction products depends on the participation of oxygen and is the result of an oxidation reaction. Therefore, anthraquinone is the product of the decarboxylation and oxidation cascade reaction of the organic small molecule co-crystal photoresist 1 under the action of ultraviolet light.

[0077] Example 2

[0078] The organic small molecule co-crystal crystal photoresist 1 obtained by the preparation method of Example 1 was evenly dispersed on a clean glass slide and placed under a 40x objective lens of a laser confocal microscope. Using a laser light source with a wavelength of 405 nm, a straight line was drawn, and the laser light power was adjusted to 0.177 mW, 0.225 mW, 0.261 mW, and 0.319 mW respectively to scan the straight line. The organic small molecule co-crystal crystal photoresist 1 after photolithography was immersed in the developer, and the products after the photoreaction were selectively removed by the developer to achieve a positive photolithography effect. The morphology of the photolithographed straight lines under different power conditions was analyzed by scanning electron microscopy, as Figure 6As shown, with the increase of the laser power, the width of the lithography straight line gradually increases, and the forward lithography straight lines with widths of 118 nm, 278 nm, 451 nm, and 712 nm are obtained respectively.

[0079] In addition, repeat the above experiment, and only adjust the laser power to 0.127 mW, 0.175 mW, 0.225 mW, 0.262 mW, 0.321 mW, and 0.362 mW respectively to scan and obtain the lithography straight lines. Use an atomic force microscope to measure the depth of the forward lithography straight lines obtained at different laser powers, and obtain the relationship between the laser power and the forward lithography depth, as Figure 7 shown, the lithography depth of the organic small molecule co-crystal crystal photoresist shows a linear positive correlation with the excitation light power of the exposure area.

[0080] The developer in Example 2 is a mixed solvent of dichloromethane and acetone with a volume ratio of 4:1.

[0081] Example 3

[0082] Use the organic small molecule co-crystal crystal photoresist 1 obtained by the preparation method of Example 1. First, put it into a container filled with the developer. The developer is a mixed solvent composed of dichloromethane and acetone with a volume ratio of 4:1, and the bottom of the container is glass. Place it on a digital light processing projection device, and use this device to project the 385-nanometer two-dimensional pattern LED light (light power is 0.376 mW) onto the surface of the organic small molecule co-crystal crystal photoresist 1. The exposure time is 90 seconds, and an in-situ three-dimensional forward lithography structure can be directly obtained. The two-dimensional pattern imported by the digital light processing projection device is as Figure 8 shown, and the scanning electron microscope image and atomic force microscope image of the obtained three-dimensional forward lithography structure are as Figure 9 shown.

[0083] Example 4

[0084] Prepare the small molecule co-crystal crystal photoresist 2 formed by the co-assembly of 9,10-anthracenedicarboxylic acid molecules and 2-methylmorpholine. The preparation method is as follows:

[0085] (1) Dissolve 15 mg of the powder 9,10-anthracenedicarboxylic acid molecular solid in 75 mL of acetone to obtain a 9,10-anthracenedicarboxylic acid monomer solution with a concentration of 0.96 mmol / L. Dissolve 10 μL of 2-methylmorpholine liquid completely in 25 mL of acetone to obtain a 2-methylmorpholine solution with a concentration of 3.74 mmol / L.

[0086] (2) Mix 75 mL of 9,10-anthracenedicarboxylic acid monomer solution (0.96 mmol / L) in step (1) with 2-methylmorpholine acetone solution (25 mL, 3.74 mmol / L) at a volume ratio of 3:1. Let it stand at room temperature for 12 hours to prepare organic small molecule co-crystal crystal photoresist 2 at the bottom of the solution. This organic small molecule co-crystal crystal photoresist 2 is obtained by co-assembly through hydrogen bonds and electrostatic interactions between 9,10-anthracenedicarboxylic acid and 2-methylmorpholine molecules.

[0087] Disperse the organic small molecule co-crystal crystal photoresist 2 obtained in step (2) in n-hexane and wash and filter it three times repeatedly to obtain the organic small molecule co-crystal crystal photoresist 2 after removing surface impurities. The scanning electron microscope characterization of the crystal morphology of this organic small molecule co-crystal crystal photoresist is as Figure 10 shown. It can be seen that the crystal shape of the organic small molecule co-crystal crystal photoresist 2 prepared in this example is a regular cube-like shape, with a length of 50 μm, a width of 50 μm, and a height in the range of 10 - 100 microns. The crystal of the organic small molecule co-crystal crystal photoresist 2 prepared in this example has a flat surface.

[0088] Test Example 4

[0089] Use the organic small molecule co-crystal crystal photoresist 2 obtained by the preparation method of Example 4, and use a Lambda1050+ ultraviolet-visible spectrophotometer to test its effective ultraviolet-visible absorption spectrum range. The results are as Figure 11 shown. It can be seen from this that the ultraviolet-visible light absorption range of the organic small molecule co-crystal crystal photoresist 2 covers a wavelength range of 300 - 430 nanometers.

[0090] Test Example 5

[0091] Perform nuclear magnetic resonance hydrogen spectrum analysis on the chemical composition of the organic small molecule co-crystal crystal photoresist 2 obtained by the preparation method of Example 4: Dissolve the organic small molecule co-crystal crystal photoresist 2 in deuterated dimethyl sulfoxide, and obtain a nuclear magnetic spectrum as Figure 12 shown. Through the analysis of the chemical shift peak position and integral information, it can be known that the molar ratio of 9,10-anthracenedicarboxylic acid molecules to 2-methylmorpholine molecules in the organic small molecule co-crystal crystal photoresist 2 is 1:1.

[0092] Test Example 6

[0093] Perform photoreaction product analysis on the organic small molecule co-crystal crystal photoresist 2 obtained by the preparation method of Example 4:

[0094] 10 mg of the organic small molecule co-crystal crystal photoresist 2 was evenly coated on a glass slide and irradiated with 405 nm LED light (light intensity: 190 mW) in an oxygen environment. It was remixed every minute of irradiation, and samples were taken after 0 minute, 2 minutes, 4 minutes, and 6 minutes of irradiation respectively. The test samples at different time points and the anthraquinone sample (blank sample) were dissolved in deuterated dimethyl sulfoxide for nuclear magnetic resonance hydrogen spectrum analysis. The nuclear magnetic data spectra are as shown in Figure 13 shown. It can be seen from Figure 13 that as the irradiation time increases, the generated anthraquinone in the test sample gradually increases, indicating that the organic small molecule co-crystal crystal photoresist 2 generates the oxidation product anthraquinone under near-ultraviolet light irradiation within the absorption range.

[0095] To further verify the generation mechanism of anthraquinone, a deoxygenation control experiment was carried out. The organic small molecule co-crystal crystal photoresist 2 was irradiated under the same conditions in an anaerobic environment, and control samples were taken after 0 minute, 3 minutes, 6 minutes, 9 minutes, and 14 minutes of irradiation respectively. No generation of anthraquinone was detected in the control samples under anaerobic conditions. It can be seen that the generation of anthraquinone in the photoreaction products depends on the participation of oxygen and is the result of an oxidation reaction. Therefore, anthraquinone is the product of the decarboxylation and oxidation cascade reaction of the organic small molecule co-crystal photoresist 2 under ultraviolet light.

[0096] Example 5

[0097] The organic small molecule co-crystal crystal photoresist 2 obtained by the preparation method of Example 4 was first placed in a container filled with a developer. The developer is a mixed solvent composed of dichloromethane and acetone with a volume ratio of 4:1, and the bottom of the container is glass. Subsequently, the container was placed on a digital light processing projection device, and the device was used to project 385 nm two-dimensional pattern LED light (light power: 0.376 mW) onto the surface of the organic small molecule co-crystal crystal photoresist 2. The exposure time was 90 seconds, and an in-situ three-dimensional positive photolithography structure could be directly obtained. The two-dimensional pattern imported by the digital light processing projection device is as shown in Figure 14 shown, and the scanning electron microscope image of the obtained three-dimensional positive photolithography structure is as shown in Figure 15 shown.

[0098] The above describes the exemplary embodiments of the present invention. However, the protection scope of this application is not limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made by those skilled in the art within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An organic small molecule co-crystal photoresist, characterized in that, The organic small molecule co-crystal crystal photoresist is obtained by co-assembling 9,10-anthracenedicarboxylic acid and small molecule amines; the co-assembly is achieved through the combination of intermolecular hydrogen bonds and electrostatic interactions; The small molecule amines are selected from at least one of morpholine, thiomorpholine, triethylamine, triethanolamine, and methylpiperazine.

2. The organic small molecule co-crystal photoresist according to claim 1, wherein The surface of the crystal of the organic small molecule co-crystal crystal photoresist is flat; Preferably, the crystal of the organic small molecule co-crystal crystal photoresist has a regular three-dimensional structure; Preferably, the organic small molecule co-crystal crystal photoresist undergoes a decarboxylation and / or oxidation reaction under the irradiation of near-ultraviolet light; Preferably, the organic small molecule co-crystal crystal photoresist has positive photolithography performance.

3. The preparation method of the small molecule co-crystal crystal photoresist according to claim 1 or 2, characterized in that, The preparation method specifically includes the following steps: (1) Dissolve 9,10-anthracenedicarboxylic acid in a solvent to obtain a monomer solution of 9,10-anthracenedicarboxylic acid; that is, dissolve small molecule amines in a solvent to obtain a monomer solution of small molecule amines; (2) Mix the monomer solution of 9,10-anthracenedicarboxylic acid obtained in step (1) with the monomer solution of small molecule amines. After co-assembly of 9,10-anthracenedicarboxylic acid and small molecule amines, age to obtain the small molecule co-crystal crystal photoresist.

4. The preparation method according to claim 3, characterized in that, In the monomer solution of 9,10-anthracenedicarboxylic acid, the concentration of 9,10-anthracenedicarboxylic acid is 0.1-1 mg / mL; 5. The preparation method according to claim 3, wherein Preferably, the concentration of the monomer solution of small molecule amines is 0.1-10 μL / mL. In step (1), the solvents in the monomer solution of 9,10-anthracenedicarboxylic acid and the monomer solution of small molecule amines may be the same or different, and are independently selected from one of acetone, tetrahydrofuran, and ethanol; Preferably, in step (2), when mixing, the volume ratio of the monomer solution of anthracenedicarboxylic acid to the monomer solution of small molecule amines is 1:1-10:1; Preferably, the co-assembly refers to the intermolecular hydrogen bond and / or electrostatic interaction between 9,10-anthracenedicarboxylic acid and small molecule amines; Preferably, the aging refers to standing under conditions above 30 °C.

7. A method for in-situ lithography, characterized in that, 6. Application of the small molecule co-crystal crystal photoresist according to claim 1 or 2 in the fields of microelectronics and semiconductor manufacturing, micro-nano processing or photolithography. The method of in-situ photolithography includes: performing photolithography on the organic small molecule co-crystal crystal photoresist according to claim 1 or 2 under light illumination conditions to obtain a target pattern; 8. The method of in-situ lithography according to claim 7, wherein The organic small molecule co-crystal crystal photoresist is contacted with a developer before light illumination, or the organic small molecule co-crystal crystal photoresist is contacted with a developer after photolithography. The developer is selected from at least two or more organic solvents; Preferably, the two-dimensional substrate is selected from at least one of a glass sheet, a quartz sheet, a silicon wafer, a mica sheet, and graphite; 9. The method of in-situ lithography according to claim 7, characterized in that, Preferably, the light illumination conditions are specifically a near-ultraviolet light excitation light source. During photolithography, control the exposure area range of light illumination. The organic small molecule co-crystal crystal photoresist located in the exposure area undergoes a reaction to obtain a light illumination product, and the light illumination product is directly dissolved in the developer, while the organic small molecule co-crystal crystal photoresist located in the non-exposure area remains, achieving a fast in-situ positive photolithography effect; Preferably, the lithography depth of the organic small molecule co-crystal photoresist has a linear relationship with the cumulative exposure time of the exposed area; Preferably, the lithography depth of the organic small molecule co-crystal photoresist has a linear relationship with the exposure intensity of the exposed area.

10. A three-dimensional forward lithography method, the three-dimensional forward lithography method comprising: Immerse the organic small molecule co-crystal photoresist according to Claim 1 or 2 in a developer solution, and under light illumination conditions, adjust the exposure amount at different spatial positions in the exposed area to obtain an in-situ three-dimensional positive lithography structure.

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