A pdms-based hybrid block copolymer, and a preparation method and application thereof

Abstract

This invention discloses a PDMS-based hybrid block copolymer, its preparation method, and its applications. The structural formula of the PDMS-based hybrid block copolymer of this invention is as follows: [Formula omitted for brevity], where R1 and R2 are independently selected from H, C1 to C1. 12 The alkyl, benzyl, or alkyl group is used, R3 is selected from H or phenyl, m is an integer from 6 to 56, n is an integer from 16 to 128, and t is an integer from 0 to 5. The PDMS-based hybrid block copolymer of this invention has advantages such as uniform chemical composition, precise controllable degree of polymerization and chemical composition, well-defined block linkage structure, and high self-assembly driving force. It can self-assemble into a periodic ordered structure with ultra-high resolution and ultra-high controllability, making it suitable for the manufacture of advanced semiconductor devices such as DRAM memory and 3D NAND flash memory in advanced technology nodes.

Description

Technical Field

[0001] This invention relates to the fields of polymer materials and semiconductor photolithography, specifically to a PDMS-based hybrid block copolymer, its preparation method, and its applications. Background Technology

[0002] As the semiconductor industry enters the sub-10nm technology node, traditional top-down lithography processes are facing the dual challenges of physical limitations and economic viability. Currently, while 193nm immersion lithography combined with self-aligned multiple patterning (SADP / SAQP) can achieve 14nm processes, its complex process steps lead to a sharp increase in production costs and a significant decrease in product yield. Meanwhile, although extreme ultraviolet (EUVL) lithography has been successfully implemented in advanced processes, it remains hampered by issues such as equipment cost, photon shot noise, and photoresist sensitivity. Therefore, developing an ultra-high resolution patterning technology that is both cost-effective and process-feasible has become an urgent need for the semiconductor manufacturing industry.

[0003] Directional self-assembly lithography (DSA), with its bottom-up thermodynamic-driven ordering mechanism, can overcome the optical diffraction limit and form ordered structures with feature sizes sub-10nm and even sub-5nm. Compared to existing patterning technologies, DSA technology offers three major industrial advantages: 1) Cost advantage: DSA technology eliminates the need for the complex light source system of EUVL, significantly reducing equipment investment; 2) Process advantage: Compared to SAQP technology, DSA technology reduces lithography steps by 40%–50% and shortens the production cycle by more than 30%; 3) Compatibility advantage: DSA technology is compatible with existing 300mm wafer production lines, coating, developing, and etching processes, eliminating the need to rebuild infrastructure. Based on these advantages, the International Technology Roadmap for Semiconductors (ITRS) has explicitly listed DSA technology as a key candidate for next-generation nodes. Currently, international semiconductor giants such as IBM, IMEC, and CEA-Leti have established pilot production lines for 300mm wafer DSA technology, validating its feasibility in advanced FinFET devices, 3D NAND flash memory, and DRAM capacitor manufacturing.

[0004] However, the intrinsic defects of existing block copolymer materials have become a core bottleneck hindering the industrialization of DSA technology. Specifically, these defects manifest in the following ways: 1) Polydispersity of molecular weight and other chemical defects make it difficult to precisely control the structural ordering process; 2) Insufficient driving force (χ value) for microphase separation results in a large intrinsic period of the formed pattern, making it difficult to meet the requirements of advanced processes; 3) Polymer chain entanglement leads to long structure formation time and high annealing temperature. The root cause of these problems lies in the fact that traditional block copolymer materials are essentially homologous mixtures of polymers with different degrees of polymerization, making it impossible to truly achieve high-precision control of chemical structure and self-assembly structure.

[0005] Therefore, there is an urgent need to develop a novel block copolymer with uniform chemical composition, well-defined block linkage structure, and high self-assembly driving force (high χ value) to break through the core bottleneck of DSA technology industrialization. Summary of the Invention

[0006] One of the objectives of this invention is to solve the problem that existing block copolymer material systems cannot achieve high-precision control of chemical structure and self-assembly structure, and to provide a PDMS-based hybrid block copolymer with uniform chemical composition, well-defined block connection structure, and high self-assembly driving force.

[0007] The second objective of this invention is to provide a method for preparing a PDMS-based hybrid block copolymer.

[0008] The third objective of this invention is to provide a method for preparing periodic nanopatterns.

[0009] The fourth objective of this invention is to provide an application of PDMS-based hybrid block copolymers.

[0010] The technical solution adopted in this invention is: A PDMS-based hybrid block copolymer has the following structural formula: In the formula, R1 and R2 are independently selected from H, C1 to C 12 alkyl, benzyl or R3 is selected from H or phenyl, m is an integer from 6 to 56, n is an integer from 16 to 128, and t is an integer from 0 to 5.

[0011] Preferably, the PDI (molecular weight distribution index) of the PDMS-based hybrid block copolymer is ≤1.005.

[0012] A method for preparing a PDMS-based hybrid block copolymer as described above includes the following steps: 1) Prepare three types of compounds: polyesters with orthogonal protection at both ends, polydimethylsiloxanes containing Si-H bonds on one side, and linkers containing terminal carbon-carbon double bonds. The structural formulas of these three types of compounds are as follows: Polyester with orthogonal protection at both ends: ; Polydimethylsiloxanes containing Si-H bonds on one side: ; Linkers containing terminal carbon-carbon double bonds: ; 2) Polydimethylsiloxane containing a single Si-H bond on one side is subjected to a hydrosilylation reaction with a linker containing a terminal carbon-carbon double bond to obtain a hydrosilylation product. The structural formula of the hydrosilylation product is as follows: ; 3) The benzyl group was removed from the hydrosilylation product to obtain the debenzylated hydrosilylation product. The structural formula of the debenzylated hydrosilylation product is as follows: ; 4) The tert-butyldimethylsilyl group of the orthogonally protected polyester at both ends is removed, and then esterified with the debenzylated hydrosilylation product to obtain a PDMS-based hybrid block copolymer.

[0013] Preferably, the polyester with orthogonally protected ends in step 1) is o LA n , o BA n , o OA n , o DA n , o PLA n , o AMA n One of them.

[0014] o LA n , o BA n , o OA n , o DA n , o PLA n and o AMA n The structural formula is as follows: .

[0015] Preferably, the polyester with orthogonal protection at both ends in step 1) is prepared by an iterative stepwise growth method.

[0016] Preferably, the hydrosilylation reaction in step 2) is carried out at a temperature of 60°C to 90°C for a reaction time of 8 to 12 hours.

[0017] Preferably, the esterification reaction in step 4) is carried out at room temperature for 8 to 12 hours.

[0018] A method for preparing periodic nanopatterns includes the following steps: The above-mentioned PDMS-based hybrid block copolymer was dissolved in an organic solvent, then spin-coated onto the substrate surface, followed by annealing and etching to obtain periodic nanopatterns.

[0019] Preferably, the organic solvent is at least one selected from toluene, tetrahydrofuran, acetone, and cyclohexane.

[0020] Preferably, the spin coating is performed at a spin coating speed of 2000 rpm to 10000 rpm and an ambient relative humidity of <30%, and the spin coating time is 20 s to 120 s.

[0021] Preferably, the substrate is a silicon substrate.

[0022] Preferably, the annealing is carried out at a temperature of 100℃ to 220℃ for a time of 0.5h to 2h.

[0023] Preferably, the annealing is carried out in an air atmosphere, a nitrogen atmosphere, an argon atmosphere, or a vacuum environment (vacuum degree <0.01mbar).

[0024] Preferably, the etching method is plasma etching, the etching gas is at least one of O2, Ar, Cl2, SF6, and CF4, the etching power is 5W to 100W, and the etching time is 10s to 300s.

[0025] Preferably, the period of the periodic nanopattern is 8nm to 20nm.

[0026] Application of a PDMS-based hybrid block copolymer as described above in the fabrication of microelectronic devices.

[0027] The beneficial effects of the present invention are as follows: The PDMS-based hybrid block copolymer of the present invention has the advantages of uniform chemical composition, precise control of polymerization degree and chemical composition, clear block connection structure, and high self-assembly driving force. It can self-assemble into a periodic ordered structure with ultra-high resolution (below 10nm) and ultra-high control precision (0.2nm), which is suitable for the manufacture of advanced semiconductor devices such as DRAM memory and 3D NAND flash memory in advanced technology nodes.

[0028] Specifically: 1) High precision of molecular structure: This invention achieves precise control of the chain length of polyester and PDMS blocks by using the iterative growth method and the orthogonal protection / deprotection strategy, ensuring the uniqueness of the chemical structure. The resulting hybrid block copolymer has a PDI ≤ 1.005, which is much lower than that of commercially available and literature-reported block copolymers (PDI ≥ 1.05). 2) Rapid kinetics of self-assembly behavior: The PDMS-based hybrid block copolymer of the present invention has uniform molecular chain length and precise chemical composition, and the driving force for ordering during the thermal annealing process is significantly enhanced. It can form long-range ordered periodic nanostructures in the bulk in only 0.5h to 2h, and the annealing time is shortened by more than 50% compared with traditional block copolymers. 3) Substantial breakthrough in patterning resolution: The PDMS-based hybrid block copolymer of the present invention can stably form a high-density periodic line structure with a period as low as 8nm in the film, and the feature size has entered the sub-10nm technology node. Attached Figure Description

[0029] Figure 1 As in Example 1 o DMS 17 S 17 -PL and S 17 -PL 33 Gel permeation chromatogram.

[0030] Figure 2 As in Example 1 o DMS 17 S 17 -PL and S 17 -PL 33 MALDI-ToF MS spectrum.

[0031] Figure 3 As in Example 2 o DMS 17 S 17 -DA and S 17 -DA 25 Gel permeation chromatogram.

[0032] Figure 4 As in Example 2 o DMS 17 S 17 -DA and S 17 -DA 25 MALDI-ToF MS spectrum.

[0033] Figure 5 As in Example 3 o DMS 17 S 17-AMA and S 17 -AMA 33 Gel permeation chromatogram.

[0034] Figure 6 As in Example 3 o DMS 17 S 17 -AMA and S 17 -AMA 33 MALDI-ToF MS spectrum.

[0035] Figure 7 S in Example 1 17 -PL 33 SAXS diagram of the formed periodic nanopatterns.

[0036] Figure 8 S in Example 1 17 -PL 33 TEM image of the formed periodic nanopatterns.

[0037] Figure 9 S in Example 1 17 -PL 33 SEM image of the formed periodic nanopatterns.

[0038] Figure 10 S in Example 1 17 -PL 33 SEM image of the formed guided self-assembled nanopatterns. Detailed Implementation

[0039] The present invention will be further explained and described below with reference to specific embodiments.

[0040] Example 1: A PDMS-based hybrid block copolymer is prepared by the following method: 1) Polyester with orthogonal protection at both ends o PLA 32 Polydimethylsiloxanes containing Si-H bonds on one side o DMS 17 Preparation of PL-ene linkers containing terminal carbon-carbon double bonds: Polyester with orthogonal protection at both ends o PLA 32 Preparation ( o PLA 32 The structural formula is ): i) Mix 50 g (1.0 eq) of L-phenylalanine, 300 mL of 1,4-dioxane, 100 mL of deionized water, and 100 mL of acetic acid until homogeneous. Cool to 0 °C and slowly add 2.0 eq of tert-butyl nitrite dropwise. After the addition is complete, heat to 60 °C and stir for 6 h. Dilute with 300 mL of saturated sodium chloride solution and extract. Wash the aqueous layer three times with ethyl acetate. Collect the organic layer and wash it three times with saturated sodium chloride solution. Collect the organic layer and dry it with anhydrous magnesium sulfate. Concentrate under reduced pressure and add 100 mL of dichloromethane. Let it stand at -20 °C for 12 h (white needle-like crystals precipitate). Filter to obtain compound L-HO-PLA-COOH. Prepare compound D-HO-PLA-COOH from dextrophenylalanine using the same method. ii) Mix L-HO-PLA-COOH and D-HO-PLA-COOH evenly at a mass ratio of 1:1 to obtain racemic HO-PLA-COOH; iii) Dissolve 30 g (1.0 eq) of racemic HO-PLA-COOH in 150 mL of N,N-dimethylformamide by stirring. Then heat to 60 °C and add 1.0 eq of anhydrous potassium carbonate. Seal with oil and wait until no gas is generated. Then add 1.2 eq of benzyl bromide. Stir at 60 °C for 10 h. Then dilute with 300 mL of deionized water. Then extract with ethyl acetate in small amounts multiple times. Collect the organic layer and back-extract once with saturated sodium chloride aqueous solution. Collect the organic layer and dry it with anhydrous magnesium sulfate. Then concentrate under reduced pressure, purify by silica gel column chromatography, and then dry under vacuum to obtain the benzyl-protected compound HO-PLA (colorless oil). iv) Dissolve 30 g (1.0 eq) of HO-PLA in 600 mL of anhydrous dichloromethane by stirring, then quickly add 2.0 eq of tert-butyldimethylchlorosilane and stir for 0.5 h, then add 4.0 eq of imidazole and stir at room temperature for 2 h (monitor the reaction progress by thin-layer chromatography), then quench the reaction with saturated sodium bicarbonate aqueous solution, then extract the aqueous layer three times with dichloromethane, collect the organic layer, dry it with anhydrous magnesium sulfate, then concentrate under reduced pressure, then purify by silica gel column chromatography, and then dry under vacuum to obtain compound PLA; v) 15 g (1.0 eq) of PLA was dissolved in 150 mL of anhydrous dichloromethane by stirring. After cooling to 0 °C, 5.0 eq of boron trifluoride diethyl ether was slowly added. The reaction was carried out at room temperature for 5 h (the reaction progress was monitored by thin-layer chromatography). The reaction was then quenched by adding saturated sodium bicarbonate aqueous solution. The organic layer was extracted three times with saturated sodium chloride aqueous solution. The organic layer was collected and dried with anhydrous magnesium sulfate. The mixture was concentrated under reduced pressure. The crude product was purified by silica gel column chromatography and dried under vacuum to obtain compound HO-PLA (colorless oil). vi) Dissolve 15g (1.0eq) of PLA in 300mL of ethyl acetate with stirring, add 0.02eq of palladium-carbon catalyst (10wt%), and then stir at room temperature in a hydrogen atmosphere for 10h (monitor the reaction progress by thin-layer chromatography). Filter the reaction solution through a diatomaceous earth layer, collect the organic filtrate, concentrate under reduced pressure to obtain compound PLA-COOH (colorless viscous liquid). vii) 10 g (1.0 eq) of PLA-OH, 1.05 eq of PLA-COOH and 0.3 eq of 4-dimethylaminopyridine-p-toluenesulfonate were dissolved in 150 mL of anhydrous dichloromethane by stirring. After cooling to 0 °C, 2.0 eq of N,N'-diisopropylcarbodiimide was slowly added. The reaction was carried out at room temperature for 10 h. The mixture was concentrated under reduced pressure, and toluene was added to dissolve the concentrate. The mixture was filtered, and the filtrate was collected and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography and dried under vacuum to obtain compound PLA2 (colorless oil). viii) Repeat steps v) to vii) by replacing PLA with PLA2 to obtain a polyester with orthogonal protection at both ends. o PLA 32 ; Polydimethylsiloxane containing Si-H bonds on one side o DMS 17 Preparation: I) Under a nitrogen atmosphere, 150.0 g (1.0 eq) of hexamethylcyclotrisiloxane, 70.2 g (1.1 eq) of dimethylchlorosilane, 35 mL of acetonitrile and 2.25 mL of N,N-dimethylformamide were mixed evenly, stirred at room temperature for 72 h, and then concentrated under reduced pressure to obtain compound Cl-Si4-H (colorless liquid). II) Mix 25 mL of phosphate buffer (PB, 1 M, pH=7), 70 mL of dioxane, and 0.001 eq of palladium-carbon catalyst (10 wt%) until homogeneous. After cooling to 0 °C, slowly add 20 mL of dioxane solution containing 1 eq of trimethylsilane. After returning to room temperature, stir overnight. Filter with diatomaceous earth. Extract the aqueous layer of the filtrate with toluene in small amounts multiple times. Back-extract the organic layer with deionized water. Collect the organic layer, add anhydrous magnesium sulfate, and then vacuum dry to obtain compound CH3-Si-OH (colorless oil). III) Under a nitrogen atmosphere, 31.60 g (1.0 eq) of Cl-Si4-H was dissolved in 150 mL of anhydrous toluene with stirring. After cooling to 0 °C, 10 mL of pyridine and 15 mL of anhydrous toluene solution containing 1 eq of CH3-Si-OH were slowly added sequentially. After returning to room temperature, the mixture was stirred overnight. The mixture was then extracted with deionized water in small batches multiple times. The organic layer was collected, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain the compound. oDMS5 (colorless, transparent oily substance); IV) Repeat steps II) to III) by replacing dimethylphenylsilane with Si5-H to obtain polydimethylsiloxane containing Si-H bonds on one side. o DMS 17 ; Preparation of PL-ene linkers containing terminal carbon-carbon double bonds: Under a nitrogen atmosphere, 3.00 g (1.0 eq) of PLA-OH, 7.75 g (2.7 eq) of silver oxide and 0.30 g (0.2 eq) of anhydrous magnesium sulfate were mixed, and 15 mL of diethyl ether was added and stirred until homogeneous. Then, 2.25 g (1.5 eq) of 3-bromo-1-propene was added, and the mixture was reacted at room temperature in the dark for 10 h. The reaction solution was then filtered through diatomaceous earth, and the filtrate was concentrated under reduced pressure. The crude product was purified by silica gel column chromatography and then vacuum dried to obtain PL-ene (a colorless oily substance) containing a terminal carbon-carbon double bond. 2) Under a nitrogen atmosphere, 100 mg of PL-ene and 354 mg of [unclear - possibly a specific compound or ingredient] were [dissolved / mixed / etc.]. o DMS 17 Dissolve in 1 mL of anhydrous toluene, then add 5 mg of the catalyst platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, stir at 80 °C for 10 h, then concentrate under reduced pressure, and finally purify by preparative-grade SEC to obtain the hydrosilylation product S. 17 -PL (colorless viscous liquid); 3) Take 200mg of S 17 -PL was dissolved in 4 mL of ethyl acetate, and then 50 mg of palladium-carbon catalyst (10 wt%) was added. The mixture was then stirred at room temperature under a hydrogen atmosphere for 8 h (the reaction progress was monitored by thin-layer chromatography). The reaction solution was then filtered through diatomaceous earth, and the organic filtrate was collected and concentrated under reduced pressure to obtain the debenzylated hydrosilylation product S. 17 -PL-COOH (colorless viscous liquid); 4) Take 100mg of S 17 -PL-COOH, 300mg o PLA 32 -OH and 6 mg of 4-dimethylaminopyridine-p-toluenesulfonate were mixed, and then 1 mL of anhydrous dichloromethane was added and stirred until homogeneous. The mixture was then cooled to 0 °C and 12 mg of N,N'-diisopropylcarbodiimide was slowly added. The mixture was reacted at room temperature for 10 h, then concentrated under reduced pressure and purified by preparative-grade SEC to obtain the PDMS-based hybrid block copolymer S. 17 -PL 33 .

[0041] Note: o DMS17 S 17 -PL and S 17 -PL 33 The structural formula is as follows: .

[0042] Structural characterization: 1) In this embodiment o DMS 17 S 17 -PL and S 17 -PL 33 The gel permeation chromatogram is as follows Figure 1 As shown.

[0043] Depend on Figure 1 It can be seen that as the reaction proceeds, the molecular weight gradually increases and the retention time decreases.

[0044] 2) In this embodiment o DMS 17 S 17 -PL and S 17 -PL 33 The matrix-assisted laser desorption / ionization time-of-flight mass spectrometry (MALDI-ToF MS) image is shown below. Figure 2 As shown.

[0045] Depend on Figure 2 It can be known that: o DMS 17 S 17 -PL and S 17 -PL 33 All showed a single peak, and the molecular weight obtained by the test was consistent with the theoretical calculation value.

[0046] Example 2: A PDMS-based hybrid block copolymer is prepared by the following method: 1) Polyester with orthogonal protection at both ends o DA 24 Polydimethylsiloxanes containing Si-H bonds on one side o DMS 17 Preparation of DA-ene, a linker containing terminal carbon-carbon double bonds: Polyester with orthogonal protection at both ends o DA 24 Preparation ( o DA 24 The structural formula is ): i) Dissolve 73 g (1.2 eq) of diethyl acetaminomalonate and 70 g (1.0 eq) of 1-bromododecane in 400 mL of acetonitrile, then add 92 g (1.0 eq) of cesium carbonate, 18 g (0.20 eq) of tetrabutylammonium bromide and 47 g (1.0 eq) of potassium iodide, and then reflux and stir at 90 °C for 24 h (monitor the reaction progress by thin-layer chromatography). Filter, concentrate the filtrate under reduced pressure, purify the crude product by silica gel column chromatography, and vacuum dry to obtain product 1 (light yellow powder). ii) Dissolve 9.3 g (2.0 eq) of sodium hydroxide in 400 mL of anhydrous ethanol-deionized water mixed solvent (the volume ratio of anhydrous ethanol to deionized water is 3:1), then add 45 g (1.0 eq) of product 1, and reflux and stir at 110 °C for 12 h. Then add 1.2 L of deionized water to dilute the reaction system, and add hydrochloric acid solution dropwise under stirring until the pH value of the reaction system drops to 1 (a large amount of white solid precipitates). Filter, wash the solid with deionized water several times, and then place it in a vacuum dryer at 60 °C for 24 h to obtain product 2 (white powder). iii) Dissolve 35 g (0.12 mol) of product 2 in 400 mL of a mixed solvent of 1,4-dioxane and 5 M sulfuric acid solution (volume ratio of 1,4-dioxane to sulfuric acid solution is 3:1), then reflux and stir at 110 °C for 12 h, then add 600 mL of deionized water to dilute the reaction system, and then add 75 mL of triethylamine under stirring to neutralize the reaction system (a large amount of white solid precipitates), filter, take the solid and wash it several times with deionized water, and then place it at 60 °C under vacuum and dry for 24 h to obtain compound H2N-DA-COOH (white powder). iv) Dissolve 30 g (1.0 eq) of H2N-DA-COOH in 500 mL of a mixed solvent of 1,4-dioxane, water and acetic acid (volume ratio of 1,4-dioxane, water and acetic acid is 3:1:1), then heat to 60 °C, and add 2.0 eq of tert-butyl nitrite dropwise under stirring (the reaction progress is monitored by thin-layer chromatography). Then add 200 mL of deionized water to dilute the reaction system, and extract with ethyl acetate three times. Take the upper organic phase and extract with deionized water three times. Then add anhydrous magnesium sulfate to dry the organic layer, and then concentrate under reduced pressure to obtain compound HO-DA-COOH (yellow-green viscous liquid). v) Dissolve 30 g (1.0 eq) of HO-DA-COOH in 300 mL of N,N-dimethylformamide, then heat to 45 °C and add 1.0 eq of anhydrous potassium carbonate. Seal with oil and wait until no gas is generated before adding 1.2 eq of benzyl bromide. React at 45 °C for 12 h. Then add 300 mL of deionized water to dilute the reaction system. Extract with ethyl acetate in small amounts several times, collect the organic layer and back-extract once with saturated sodium chloride aqueous solution. Collect the organic layer and dry it with anhydrous magnesium sulfate. Then concentrate under reduced pressure. Purify the crude product by silica gel column chromatography and dry under vacuum to obtain compound HO-DA (colorless oil). vi) Refer to Example 1 o PLA 32 The preparation method involves replacing the raw material HO-PLA in steps iv) to viii) with HO-DA, while keeping the feed ratios of other raw materials and experimental procedures unchanged, to obtain polyester with orthogonal protection at both ends. o DA 24 ; Polydimethylsiloxane containing Si-H bonds on one side o DMS 17 The preparation is the same as in Example 1; Preparation of DA-ene linkers containing terminal carbon-carbon double bonds: Under a nitrogen atmosphere, 3.00 g (1.0 eq) of HO-DA, 7.94 g (2.7 eq) of silver oxide and 0.31 g (0.2 eq) of anhydrous magnesium sulfate were mixed, and 15 mL of diethyl ether was added and stirred until homogeneous. Then, 2.30 g (1.5 eq) of 3-bromo-1-propene was added, and the mixture was reacted at room temperature in the dark for 10 h. The reaction solution was then filtered through diatomaceous earth, and the filtrate was concentrated under reduced pressure. The crude product was purified by silica gel column chromatography and dried under vacuum to obtain DA-ene (a colorless oily substance) containing a terminal carbon-carbon double bond. 2) Under a nitrogen atmosphere, 100 mg of DA-ene and 360 mg of... o DMS 17 Dissolve in 1 mL of anhydrous toluene, then add 5 mg of the catalyst platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, stir at 80 °C for 10 h, concentrate under reduced pressure, and then purify by preparative-grade SEC to obtain the hydrosilylation product S. 17 -DA (colorless viscous liquid); 3) Take 200mg of S 17 -DA was dissolved in 4 mL of ethyl acetate, and then 50 mg of palladium-carbon catalyst (10 wt%) was added. The mixture was then stirred at room temperature under a hydrogen atmosphere for 8 h (the reaction progress was monitored by thin-layer chromatography). The reaction solution was then filtered through a diatomaceous earth layer, and the organic filtrate was collected and concentrated under reduced pressure to obtain the debenzylated hydrosilylation product S. 17-DA-COOH (colorless viscous liquid); 4) Take 95mg of S 17 -DA-COOH, 300mg o DA 24 -OH and 8 mg of 4-dimethylaminopyridine-p-toluenesulfonate were mixed, and then 1 mL of anhydrous dichloromethane was added and stirred until homogeneous. The mixture was then cooled to 0 °C and 20 mg of N,N'-diisopropylcarbodiimide was slowly added. The mixture was reacted at room temperature for 10 h, then concentrated under reduced pressure and purified by preparative-grade SEC to obtain the PDMS-based hybrid block copolymer S. 17 -DA 25 .

[0047] Note: o DMS 17 S 17 -DA and S 17 -DA 25 The structural formula is as follows: .

[0048] Structural characterization: 1) In this embodiment o DMS 17 S 17 -DA and S 17 -DA 25 The gel permeation chromatogram is as follows Figure 3 As shown.

[0049] Depend on Figure 3 It can be seen that as the reaction proceeds, the molecular weight gradually increases and the retention time decreases.

[0050] 2) In this embodiment o DMS 17 S 17 -DA and S 17 -DA 25 The MALDI-ToF MS spectrum is as follows Figure 4 As shown.

[0051] Depend on Figure 4 It can be known that: o DMS 17 S 17 -DA and S 17 -DA 25 All showed a single peak, and the molecular weight obtained by the test was consistent with the theoretical calculation value.

[0052] Example 3: A PDMS-based hybrid block copolymer is prepared by the following method: 1) Polyester with orthogonal protection at both ends o AMA 32 Polydimethylsiloxanes containing Si-H bonds on one side o DMS 17 Preparation of AMA-ene, a linker containing terminal carbon-carbon double bonds: Polyester with orthogonal protection at both ends o AMA 32 Preparation ( o AMA 32 The structural formula is ): i) Dissolve 80.0 g (1.0 eq) of DL-malic acid in 300 mL of 2,2-dimethoxypropane, then add 1.18 g (0.01 eq) of p-toluenesulfonic acid monohydrate and stir slowly at room temperature for 2 h until the mixture becomes a clear yellow solution. Then add saturated sodium bicarbonate aqueous solution to quench the reaction, then add 300 mL of deionized water and 300 mL of saturated sodium chloride aqueous solution. Extract with dichloromethane in small amounts several times, wash the organic phase with saturated sodium chloride aqueous solution, dry the organic phase with anhydrous magnesium sulfate, concentrate under reduced pressure, and dry in a vacuum drying oven for 12 h to obtain product 1 (white solid). ii) Dissolve 56.72 g (1.1 eq) of product 1, 49.27 g (1.0 eq) of 1-adamantane methanol, and 3.14 mg (0.2 eq) of 4-dimethylaminopyridine-p-toluenesulfonate in 500 mL of anhydrous dichloromethane. After cooling to 0 °C, slowly add 2.0 eq of N,N'-diisopropylcarbodiimide. React at room temperature for 10 h, filter, and concentrate the filtrate under reduced pressure. Purify the crude product by silica gel column chromatography and dry under vacuum to obtain product 2 (colorless oil). iii) Dissolve 83.9 g (1.0 eq) of product 2 in 300 mL of a mixed solvent of dichloromethane, trifluoroacetic acid and deionized water (volume ratio of dichloromethane, trifluoroacetic acid and deionized water is 20:4:1). Stir the reaction at room temperature for 2 h, then slowly add saturated sodium bicarbonate aqueous solution to quench the reaction, and allow the mixture to stand to separate into layers. Collect the lower organic phase and extract the aqueous phase with 300 mL of dichloromethane. Combine the collected organic layers, dry with anhydrous magnesium sulfate, concentrate under reduced pressure, and then dry in a vacuum drying oven for 12 h to obtain compound HO-AMA-COOH (white solid). iv) Refer to Example 1 o PLA 32 The preparation method involves replacing the raw material HO-PLA-COOH in steps iii) to viii) with HO-AMA-COOH, while keeping the feed ratio of other raw materials and experimental procedures unchanged, to obtain a polyester with orthogonal protection at both ends. o AMA 32 ; Polydimethylsiloxane containing Si-H bonds on one side o DMS 17 The preparation is the same as in Example 1; Preparation of AMA-ene linkers containing terminal carbon-carbon double bonds: Under a nitrogen atmosphere, 3.00 g (1.0 eq) of HO-AMA, 5.04 g (2.7 eq) of silver oxide and 0.19 g (0.2 eq) of anhydrous magnesium sulfate were mixed, and 15 mL of diethyl ether was added and stirred until homogeneous. Then, 1.46 g (1.5 eq) of 3-bromo-1-propene was added, and the mixture was reacted at room temperature in the dark for 10 h. The reaction solution was then filtered through diatomaceous earth and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography and dried under vacuum to obtain AMA-ene (a colorless oily substance) containing a terminal carbon-carbon double bond. 2) Under a nitrogen atmosphere, 100 mg of AMA-ene and 310 mg of... o DMS 17 Dissolve in 1 mL of anhydrous toluene, then add 5 mg of the catalyst platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, stir at 80 °C for 10 h, then concentrate under reduced pressure, and finally purify by preparative-grade SEC to obtain the hydrosilylation product S. 17 -AMA (colorless viscous liquid); 3) Take 200mg of S 17 -AMA was dissolved in 4 mL of ethyl acetate, and then 50 mg of palladium-carbon catalyst (10 wt%) was added. The mixture was then stirred at room temperature under a hydrogen atmosphere for 8 h (the reaction progress was monitored by thin-layer chromatography). The reaction solution was then filtered through a diatomaceous earth layer, and the filtrate was concentrated under reduced pressure to obtain the debenzylated hydrosilylation product S. 17 -AMA-COOH (colorless viscous liquid); 4) Take 80mg of S 17 -AMA-COOH, 300mg o AMA 32 -OH and 8 mg of 4-dimethylaminopyridine-p-toluenesulfonate were dissolved in 1 mL of anhydrous dichloromethane in a sealed container. After cooling to 0 °C, 20 mg of N,N'-diisopropylcarbodiimide was slowly added. The mixture was reacted at room temperature for 10 h, then concentrated under reduced pressure and purified by preparative-grade SEC to obtain the PDMS-based hybrid block copolymer S. 17 -AMA 33 .

[0053] Note: o DMS 17 S 17 -AMA and S 17 -AMA33 The structural formula is as follows: .

[0054] Structural characterization: 1) In this embodiment o DMS 17 S 17 -AMA and S 17 -AMA 33 The gel permeation chromatogram is as follows Figure 5 As shown.

[0055] Depend on Figure 5 It can be seen that as the reaction proceeds, the molecular weight gradually increases and the retention time decreases.

[0056] 2) In this embodiment o DMS 17 S 17 -AMA and S 17 -AMA 33 The MALDI-ToF MS spectrum is as follows Figure 6 As shown.

[0057] Depend on Figure 6 It can be known that: o DMS 17 S 17 -AMA and S 17 -AMA 33 All showed a single peak, and the molecular weight obtained by the test was consistent with the theoretical calculation value.

[0058] Performance testing: 1) The PDMS-based hybrid block copolymer S from Example 1 17 PL 33 The sample was annealed at 120°C for 0.5 h in a nitrogen atmosphere (to induce microscopic phase separation), and the bulk ordered structure of the annealed sample was characterized by small-angle X-ray scattering (SAXS). The test results are as follows: Figure 7 As shown. The structure of the above-mentioned sample after sectioning was characterized using transmission electron microscopy (TEM), and the test results are as follows. Figure 8 As shown.

[0059] Depend on Figure 7 It can be seen that the position ratio of the scattering peaks is 1:√3:√7, indicating that S 17 PL 33 Self-assembly formed a highly ordered hexagonal columnar phase. The position of the first-order diffraction peak... q =0.734nm -1 The corresponding column spacing is 9.88 nm.

[0060] Depend on Figure 8 It can be seen that the hexagonal lattice structure in the figure also indicates S 17 PL 33 Self-assembly forms an ordered structure.

[0061] In summary, the PDMS-based hybrid block copolymer of the present invention can form highly ordered nanostructures with a period of less than 10 nm under short-time annealing (0.5 h), exhibiting excellent self-assembly kinetics and sub-10 nm patterning capability, and is suitable for directional self-assembly lithography processes at advanced technology nodes.

[0062] 2) Preparation of periodic nanopatterns: a) The PDMS-based hybrid block copolymer S from Example 1 17 PL 33 A 10% mass fraction solution was prepared using anhydrous toluene and then filtered through a 0.22 μm polytetrafluoroethylene filter membrane to obtain a hybrid block copolymer solution. b) The single-sided polished silicon wafer was ultrasonically cleaned with acetone, ethanol and deionized water for 1 hour each, then dried with high-purity nitrogen, and then placed in an ultraviolet-ozone cleaner for 3 hours to obtain a pre-treated silicon wafer. c) Under conditions of relative humidity <30%, the hybrid block copolymer solution was spin-coated onto the pretreated silicon wafer surface at a speed of 8000 rpm for 30 s. Then, it was annealed at 120°C for 2 h in a nitrogen atmosphere. Then, a two-step plasma etching was performed using a reactive ion etching system: the first etching step used CF4 as the etching gas, the etching power was controlled at 30 W, and the etching time was 10 s; the second etching step used O2 as the etching gas, the etching power was controlled at 15 W, and the etching time was 60 s, forming periodic nanopatterns.

[0063] Scanning electron microscope (SEM) image of periodic nanopatterns as shown below Figure 9 As shown.

[0064] Depend on Figure 9 It can be seen that the period size of the columnar pattern is 9.1 nm, which is consistent with the bulk column spacing (9.88 nm) measured by SAXS. The deviation is due to the substrate interface effect in the thin film state and the slight influence of the etching process.

[0065] 3) Preparation of guided self-assembled nanopatterns: a) The PDMS-based hybrid block copolymer S from Example 1 17 PL 33A 7% (w / w) solution was prepared using anhydrous toluene and then filtered through a 0.22 μm polytetrafluoroethylene (PTFE) membrane to obtain a hybrid block copolymer solution. b) The silicon wafer with periodic guide grooves (groove width of 65nm~800nm) was ultrasonically cleaned with acetone, ethanol and deionized water for 1h respectively, then dried with high-purity nitrogen, and then placed in a UV-ozone cleaner for 3h to obtain the pretreated silicon wafer. c) Under conditions of relative humidity <30%, the hybrid block copolymer solution was spin-coated onto the surface of the pretreated silicon wafer at a speed of 8000 rpm for 30 s. Then, it was annealed at 120°C for 2 h in a nitrogen atmosphere. Then, a two-step plasma etching was performed using a reactive ion etching system: the first etching step used CF4 as the etching gas, the etching power was controlled at 30 W, and the etching time was 10 s; the second etching step used O2 as the etching gas, the etching power was controlled at 15 W, and the etching time was 60 s, forming a guided self-assembled nanopattern.

[0066] SEM images of guided self-assembled nanopatterns are shown below. Figure 10 As shown.

[0067] Depend on Figure 10 It can be known that: S 17 PL 33 Guided self-assembly resulted in an ordered columnar pattern.

[0068] 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. A PDMS-based hybrid block copolymer, characterized in that, The structure is as follows: In the formula, R1 and R2 are independently selected from H, C1 to C 12 alkyl, benzyl or R3 is selected from H or phenyl, m is an integer from 6 to 56, n is an integer from 16 to 128, and t is an integer from 0 to 5.

2. The PDMS-based hybrid block copolymer according to claim 1, characterized in that: The PDI of the PDMS-based hybrid block copolymer is ≤1.

005.

3. A method for preparing a PDMS-based hybrid block copolymer as described in claim 1 or 2, characterized in that, Includes the following steps: 1) Prepare three types of compounds: polyesters with orthogonal protection at both ends, polydimethylsiloxanes containing Si-H bonds on one side, and linkers containing terminal carbon-carbon double bonds. The structural formulas of these three types of compounds are as follows: Polyester with orthogonal protection at both ends: ; Polydimethylsiloxanes containing Si-H bonds on one side: ; Linkers containing terminal carbon-carbon double bonds: ; 2) Polydimethylsiloxane containing a single Si-H bond on one side is subjected to a hydrosilylation reaction with a linker containing a terminal carbon-carbon double bond to obtain a hydrosilylation product. The structural formula of the hydrosilylation product is as follows: ； 3) The benzyl group was removed from the hydrosilylation product to obtain the debenzylated hydrosilylation product. The structural formula of the debenzylated hydrosilylation product is as follows: ； 4) The tert-butyldimethylsilyl group of the orthogonally protected polyester at both ends is removed, and then esterified with the debenzylated hydrosilylation product to obtain a PDMS-based hybrid block copolymer.

4. The method for preparing the PDMS-based hybrid block copolymer according to claim 3, characterized in that: Step 1) The polyester with orthogonal protection at both ends is prepared by an iterative stepwise growth method.

5. The method for preparing the PDMS-based hybrid block copolymer according to claim 3, characterized in that: Step 2) The hydrosilylation reaction is carried out at a temperature of 60℃~90℃ for a reaction time of 8h~12h.

6. The method for preparing the PDMS-based hybrid block copolymer according to claim 3, characterized in that: Step 4) The esterification reaction is carried out at room temperature for 8 to 12 hours.

7. A method for preparing periodic nanopatterns, characterized in that, The process includes the following steps: dissolving the PDMS-based hybrid block copolymer as described in claim 1 or 2 in an organic solvent, then spin-coating it onto a substrate surface, followed by annealing and etching to obtain a periodic nanopattern.

8. The method for preparing periodic nanopatterns according to claim 7, characterized in that: The annealing is performed at a temperature of 100℃ to 220℃ for a time of 0.5h to 2h; the etching method is plasma etching, the etching gas is at least one of O2, Ar, Cl2, SF6, and CF4, the etching power is 5W to 100W, and the etching time is 10s to 300s.

9. The method for preparing periodic nanopatterns according to claim 7 or 8, characterized in that: The periodic nanopattern has a period of 8 nm to 20 nm.

10. The application of the PDMS-based hybrid block copolymer as described in claim 1 or 2 in the fabrication of microelectronic devices.

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