Preparation method of superhydrophilic template stamp
By preparing a nanoforest on a stamp substrate and performing hydrophilic and hydrophobic treatment, a superhydrophilic stamp part and a hydrophobic isolation groove are formed, which solves the problems of temperature sensitivity and decreased microstructure precision in existing transfer processes, and achieves efficient and reliable pattern transfer.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SUZHOU RES MATERIALS MICRONANO TECH CO LTD
- Filing Date
- 2022-12-28
- Publication Date
- 2026-05-19
AI Technical Summary
Existing transfer processes have high requirements for temperature and time. Flexible substrates cause a decrease in the positional accuracy of microstructures during the replication process. In addition, the process is complex and has poor versatility, which is a fatal defect, especially in diffraction imaging elements.
A method for preparing a superhydrophilic template stamp is adopted. By preparing a nanoforest on the stamp substrate and performing hydrophilic and hydrophobic treatment, a superhydrophilic stamp part and a hydrophobic isolation groove are formed. The thickness of the transfer layer is controlled by the difference between hydrophilicity and hydrophobicity, thereby realizing the transfer of the photolithographic template.
It improves the positioning accuracy of microstructures, reduces process complexity, and enhances preparation efficiency and reliability. It is suitable for repeated use and is not easily damaged. It is also suitable for transfer printing on water-based materials and organic solvents.
Smart Images
Figure CN116332120B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a preparation method, and more particularly to a method for preparing a superhydrophilic template stamp. Background Technology
[0002] Transfer printing is a technique that uses a stamp to transfer a pattern made on a donor substrate to a recipient substrate. Due to its advantages such as strong compatibility and room temperature operation, it is widely used in fields such as microelectromechanical systems (MEMS) and micro-nano fabrication technology.
[0003] Currently, commonly used transfer processes include stamp transfer and heat-release tape transfer. Heat-release tape transfer requires precise control of transfer temperature and time. Water-soluble tapes decompose upon contact with water, but leave small amounts of residue on the surface, causing contamination. PDMS is the most widely used stamp material in flexible transfer processes, offering the highest process feasibility. However, due to the inherently poor dimensional stability of the PDMS flexible substrate, shrinkage or expansion is unavoidable during replication.
[0004] Although the changes in microstructure are usually small, the accumulation of these changes on a macroscopic scale manifests as a decrease in the positional accuracy of the microstructure. This decrease in positional accuracy becomes a fatal flaw, especially when flexible substrates are used in diffraction imaging elements. Furthermore, most transfer methods are complex and lack versatility. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method for preparing a superhydrophilic template stamp, which can effectively realize the transfer of photolithographic template, is compatible with existing processes, reduces process complexity, and improves preparation efficiency and reliability.
[0006] According to the technical solution provided by the present invention, a method for preparing a superhydrophilic template stamp includes the following steps:
[0007] A stamp substrate is provided, and a nanoforest is prepared on one surface of the stamp substrate;
[0008] Hydrophilic treatment of the nanoforest on the stamp substrate;
[0009] The above-mentioned hydrophilic-treated nanoforest and stamp substrate are processed to form the desired stamp pattern, wherein the stamp pattern includes several superhydrophilic stamp parts formed based on the hydrophilic-treated nanoforest and several hydrophobic isolation grooves formed by etching the stamp substrate.
[0010] The stamp substrate includes silicon substrate, glass substrate, quartz substrate, sapphire substrate or smooth substrate with epitaxial layer.
[0011] When the stamp substrate is a non-hydrophilic substrate, the nanoforest on the stamp substrate is hydrophilicized by depositing a hydrophilic film on the nanoforest or immersing the nanoforest on the stamp substrate in a hydrophilic solution.
[0012] The treatment of nanoforests after hydrophilic post-treatment and the processing of stamps include:
[0013] Prepare a nanoforest mask layer covering the nanoforest;
[0014] The nanoforest mask layer is patterned to obtain several nanoforest mask layer windows that penetrate the nanoforest mask layer;
[0015] Deep trench etching of the stamp substrate was performed using a nanoforest mask layer window to prepare an isolation trench recessed within the stamp substrate.
[0016] The inner wall of the isolation tank is treated with hydrophobic material to obtain a hydrophobic isolation tank.
[0017] The nanoforest mask layer comprises a photoresist nanoforest mask made of photosensitive photoresist.
[0018] The photoresist nanoforest mask includes ultraviolet photoresist, deep ultraviolet photoresist, X-ray photoresist, electron beam photoresist, or ion beam photoresist.
[0019] When performing hydrophobic treatment on the inner wall of the isolation tank, this includes coating the inner wall of the isolation tank with a hydrophobic film or using a hydrophobic solution to perform hydrophobic treatment on the inner wall of the isolation tank.
[0020] When preparing a nanoforest on one surface of a stamp substrate, the following steps are included:
[0021] A substrate polymer layer is prepared on one surface of a stamp substrate;
[0022] Plasma bombardment of the substrate polymer layer is used to form substrate polymer nanofibers.
[0023] A nanoforest was fabricated on a stamp substrate by etching a stamp substrate using substrate polymer nanofibers as a mask.
[0024] Remove the substrate polymer nanofibers.
[0025] When bombarding the substrate polymer layer with plasma, the plasma used includes one or more combinations of oxygen plasma or carbon tetrafluoride plasma and argon plasma, helium plasma, nitrogen plasma or methane plasma.
[0026] The substrate polymer layer includes PI.
[0027] The advantages of this invention are: the stamp pattern has a superhydrophilic stamp portion and a hydrophobic isolation groove. Utilizing the difference between hydrophilic and hydrophobic properties, the transferred patterns do not stick together, and the thickness of the transfer layer can be controlled by adjusting the liquid viscosity and the hydrophilic / hydrophobic state. The superhydrophilic stamp portion and hydrophobic isolation groove within the stamp pattern can be adjusted and modified according to the actual needs of the transfer material. Therefore, it can achieve not only the transfer of water-based materials but also the transfer of organic solvent solutions such as photoresists and inks.
[0028] While hydrophilic nanofibers may also serve as transfer templates, nanofibers are too fragile and easily collapse when wet. This invention prepares nanofibers on a stamp substrate, which can retain the precision of the nanofibers while improving the quality of the stamp. It can be reused multiple times without deformation, is easy to clean, and is not prone to damaging the stamp pattern. It can also be applied to the molding of flexible templates, which can greatly improve the precision of the template stamp, achieve submicron precision transfer, be compatible with existing processes, reduce process complexity, and improve the efficiency and reliability of preparation. Attached Figure Description
[0029] Figures 1 to 7 This is a cross-sectional view of the preparation process steps according to an embodiment of the present invention, wherein,
[0030] Figure 1 This is a cross-sectional view of the substrate polymer layer prepared according to the present invention.
[0031] Figure 2 This is a cross-sectional view of the substrate polymer nanofibers prepared according to the present invention.
[0032] Figure 3 This is a cross-sectional view of the substrate nanoforest prepared according to the present invention.
[0033] Figure 4 This is a cross-sectional view of the nanoforest mask layer prepared according to the present invention.
[0034] Figure 5 This is a cross-sectional view of the patterned nanoforest mask layer of the present invention.
[0035] Figure 6 This is a cross-sectional view of the isolation groove prepared according to the present invention.
[0036] Figure 7 This is a cross-sectional view of the hydrophobic isolation groove prepared according to the present invention.
[0037] Figure 8 This is a schematic diagram of one usage state of the present invention.
[0038] Explanation of reference numerals in the attached figures: 1-Stamp substrate, 2-Substrate polymer layer, 3-Acceptor substrate, 4-Substrate polymer nanofibers, 5-Nanoforest, 6-Nanoforest mask layer, 7-Nanoforest mask layer window, 8-Isolation trench, 9-Superhydrophilic stamp part, 10-Hydrophobic isolation trench. Detailed Implementation
[0039] The present invention will be further described below with reference to specific accompanying drawings and embodiments.
[0040] In order to effectively achieve the transfer of photolithographic templates, ensure compatibility with existing processes, and reduce process complexity, in one embodiment of the present invention, the method for preparing a superhydrophilic template stamp includes the following steps:
[0041] A stamp substrate 1 is provided, and a nanoforest 5 is prepared on one surface of the stamp substrate 1;
[0042] Hydrophilic treatment was applied to the nanoforest 5 on the stamp substrate 1;
[0043] The above-mentioned hydrophilic nanoforest and stamp substrate 1 are processed to form the desired stamp pattern, wherein the stamp pattern includes a plurality of superhydrophilic stamp parts 9 formed based on the hydrophilic nanoforest 5 and a plurality of hydrophobic isolation grooves 10 formed by etching the stamp substrate 1.
[0044] In specific implementation, the stamp substrate 1 includes a silicon substrate, a glass substrate, a quartz substrate, a sapphire substrate, or a smooth substrate with an epitaxial layer. The type of stamp substrate 1 can be selected as needed to meet the requirements of stamp fabrication. Figures 1-3 The image shows an embodiment of fabricating a nanoforest 5 on a stamp substrate 1, specifically:
[0045] When preparing a nanoforest on one surface of the stamp substrate 1, the following steps are included:
[0046] A substrate polymer layer 2 is prepared on one surface of the stamp substrate 1;
[0047] Plasma bombardment is performed on the substrate polymer layer 2 to form substrate polymer nanofibers 4 using the substrate polymer layer 2;
[0048] The substrate polymer nanofibers 4 were used as a mask to etch the stamp substrate 1 in order to prepare a nanoforest 5 on the stamp substrate 1.
[0049] Remove the substrate polymer nanofibers 4.
[0050] Figure 1This is a schematic diagram of a substrate polymer layer 2 formed on the surface of a stamp substrate 1. The substrate polymer layer 1 includes PI (polyimide). When preparing the substrate polymer layer 2 on the stamp substrate 1, the substrate polymer layer 2 can be prepared using liquid polyimide (PI) or solid PI, depending on which substrate polymer layer 2 can be prepared as required.
[0051] Figure 2 This diagram illustrates the preparation of polymer nanofibers 4 by plasma bombardment of the substrate polymer layer 2. The plasma used for bombardment of the substrate polymer layer 2 includes one or more combinations of oxygen plasma or carbon tetrafluoride plasma with argon plasma, helium plasma, nitrogen plasma, or methane plasma. Specifically, it can be a combination of oxygen plasma with one or more of argon plasma, helium plasma, nitrogen plasma, or methane plasma, or a combination of carbon tetrafluoride plasma with one or more of argon plasma, helium plasma, nitrogen plasma, or methane plasma. The process conditions for bombarding the substrate polymer layer with plasma to form the substrate polymer nanofibers 4 can be consistent with existing methods, specifically designed to ensure the successful preparation of the substrate polymer nanofibers 4.
[0052] After forming the substrate polymer nanofibers 4, the substrate polymer nanofibers 4 are used as a mask to perform dry etching on the stamp substrate 1, such as dry anisotropic etching. Different etching methods, such as ICP etching, RIE etching, and IBE etching, can be selected according to the substrate to obtain a nanoforest 5 on the stamp substrate 1 after dry etching. The specific preparation of the nanoforest 5 can be determined according to the process selection.
[0053] The substrate polymer nanofibers 4 are removed using techniques commonly used in this field. After removal, the distribution of the nanoforests 5 on the stamp substrate 1 is as follows. Figure 3 As shown, a nanoforest 5 is fabricated on the stamp substrate 1.
[0054] Although nanoforest 5 is hydrophilic after preparation, it needs to be hydrophilicized in seal applications to form superhydrophilic properties.
[0055] Depending on the type of the stamp substrate 1, the stamp substrate 1 can generally be a hydrophilic substrate or a non-hydrophilic substrate. Therefore, in one embodiment of the present invention, when the stamp substrate 1 is a non-hydrophilic substrate, the hydrophilic treatment of the nanoforest 5 on the stamp substrate 1 includes depositing a hydrophilic film on the nanoforest 1 or immersing the nanoforest on the stamp substrate 1 in a hydrophilic solution.
[0056] Specifically, the hydrophilic film can be a silicon oxide film, and the hydrophilic solution can be a solution of polymer materials such as polypropylene. The method of hydrophilic treatment of the stamp substrate 1 and the nanoforest 5 can be selected as needed, based on the requirement of achieving the desired hydrophilic treatment.
[0057] In one embodiment of the present invention, the treatment of the hydrophilic post-treatment nanoforest and the stamp treatment 1 includes:
[0058] Prepare a nanoforest mask layer 6 covering the nanoforest 5;
[0059] The nanoforest mask layer 6 is patterned to obtain several nanoforest mask layer windows 7 that penetrate the nanoforest mask layer 6.
[0060] The nanoforest mask layer window 7 is used to perform deep trench etching on the stamp substrate 1 to prepare the isolation trench 8 recessed in the stamp substrate 1;
[0061] The inner wall of the isolation tank 8 is hydrophobically treated to obtain the hydrophobic isolation tank 10.
[0062] Specifically, the nanoforest mask layer 6 includes a photoresist nanoforest mask made of photosensitive photoresist. The nanoforest mask layer 6 can be fabricated on the nanoforest 5 using existing process conditions, such as... Figure 4 As shown, the photoresist nanoforest mask includes ultraviolet photoresist, deep ultraviolet photoresist, X-ray photoresist, electron beam photoresist, or ion beam photoresist.
[0063] After preparing the nanoforest mask layer 6, the nanoforest mask layer 6 can be patterned using techniques commonly used in this field to obtain several nanoforest mask layer windows 7. These windows expose the corresponding nanoforests 5, while the remaining nanoforests 5 are covered by the nanoforest mask layer 6. Figure 5 As shown.
[0064] Deep trench etching is performed on the stamp substrate 1 using the nanoforest mask layer window 7. The process conditions for deep trench etching can be selected as needed. The nanoforest 5 covered by the nanoforest mask layer 6 is unaffected during deep trench etching, thus obtaining an isolation trench 8 that corresponds directly to the nanoforest mask layer window 7. The depth of the isolation trench 8 needs to be less than the thickness of the stamp substrate 1. Figure 6 As shown.
[0065] In practice, when performing deep trench etching on the stamp substrate 1, dry etching can be used, that is, a nanoforest structure is also formed in the isolation trench 8.
[0066] When performing hydrophobic treatment on the inner wall of the isolation tank 8, it may include depositing a hydrophobic film on the inner wall of the isolation tank 8 or performing hydrophobic treatment on the inner wall of the isolation tank 8 using a hydrophobic solution. Specifically, the hydrophobic film may be a silicon nitride film, and the hydrophobic solution may be a solution of polymer materials such as silane coupling agents. The method and process of hydrophobic treatment can be selected as needed, based on achieving the required hydrophobic treatment.
[0067] After hydrophobic treatment of the isolation trench 8, the hydrophobic isolation trench 10 is obtained. Of course, after obtaining the hydrophobic isolation trench 10, the nanoforest mask layer 6 covering the nanoforest 5 needs to be removed, such as... Figure 7 As shown above, the nanoforest 5 covered by the nanoforest mask layer 6 ultimately forms the superhydrophilic stamp part 9. Specifically, when a nanoforest structure is formed in the isolation groove 8, the nanoforest structure also needs to be hydrophobically treated during the hydrophobic treatment. The isolation groove 8 and the nanoforest structure are used to form a hydrophobic isolation groove 10, which can improve the isolation effect of the non-transfer area.
[0068] The distribution of the superhydrophilic stamp portion 9 and the hydrophobic isolation groove 10 on the stamp substrate 1 is generally related to the pattern to be transferred, that is, determined according to the application scenario required for the transfer. Figure 8 This is a usage diagram of the present invention, in which the superhydrophilic stamp part 9 can be used to transfer the image to be transferred onto the host substrate 3.
[0069] As explained above, the stamp pattern has a superhydrophilic stamp portion 9 and a hydrophobic isolation groove 10. Utilizing the difference between hydrophilic and hydrophobic properties, the transferred patterns do not stick together. Furthermore, the thickness of the transfer layer can be controlled by adjusting the liquid viscosity and the hydrophilic / hydrophobic state. The superhydrophilic stamp portion 9 and the hydrophobic isolation groove 10 within the stamp pattern can be adjusted and modified according to the actual needs of the transfer material. Therefore, it can achieve not only the transfer of water-based materials but also the transfer of organic solvent solutions such as photoresists and inks.
[0070] While hydrophilic nanofibers may also serve as transfer templates, nanofibers are too fragile and easily collapse when wet. This invention prepares nanofibers 5 on a stamp substrate 1, which can retain the precision of the nanofibers while improving the quality of the stamp. It can be reused multiple times without deformation, is easy to clean, and is not prone to damaging the stamp pattern. It can also be applied to the molding of flexible templates, which can greatly improve the precision of the template stamp, achieve submicron precision transfer, be compatible with existing processes, reduce process complexity, and improve the efficiency and reliability of preparation.
[0071] The above-described embodiments are merely illustrative of the implementation methods of the present invention, but should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.
Claims
1. A method for preparing a superhydrophilic template stamp, characterized in that, The method for preparing the seal includes the following steps: A stamp substrate is provided, and a nanoforest is prepared on one surface of the stamp substrate; Hydrophilic treatment of the nanoforest on the stamp substrate; The above-mentioned hydrophilic-treated nanoforest and stamp substrate are processed to form the desired stamp pattern, wherein the stamp pattern includes several superhydrophilic stamp parts formed based on the hydrophilic-treated nanoforest and several hydrophobic isolation grooves formed by etching the stamp substrate.
2. The method for preparing the superhydrophilic template stamp according to claim 1, characterized in that, The stamp substrate includes silicon substrate, glass substrate, quartz substrate, sapphire substrate or smooth substrate with epitaxial layer.
3. The method for preparing the superhydrophilic template stamp according to claim 1, characterized in that, When the stamp substrate is a non-hydrophilic substrate, the nanoforest on the stamp substrate is hydrophilicized by depositing a hydrophilic film on the nanoforest or immersing the nanoforest on the stamp substrate in a hydrophilic solution.
4. The method for preparing the superhydrophilic template stamp according to claim 1, characterized in that, The treatment of nanoforests after hydrophilic post-treatment and the processing of stamps include: Prepare a nanoforest mask layer covering the nanoforest; The nanoforest mask layer is patterned to obtain several nanoforest mask layer windows that penetrate the nanoforest mask layer; Deep trench etching of the stamp substrate was performed using a nanoforest mask layer window to prepare an isolation trench recessed within the stamp substrate. The inner wall of the isolation tank is treated with hydrophobic material to obtain a hydrophobic isolation tank.
5. The method for preparing the superhydrophilic template stamp according to claim 4, characterized in that, The nanoforest mask layer comprises a photoresist nanoforest mask made of photosensitive photoresist.
6. The method for preparing the superhydrophilic template stamp according to claim 5, characterized in that, The photoresist nanoforest mask includes ultraviolet photoresist, deep ultraviolet photoresist, X-ray photoresist, electron beam photoresist, or ion beam photoresist.
7. The method for preparing the superhydrophilic template stamp according to claim 4, characterized in that, When performing hydrophobic treatment on the inner wall of the isolation tank, this includes coating the inner wall of the isolation tank with a hydrophobic film or using a hydrophobic solution to perform hydrophobic treatment on the inner wall of the isolation tank.
8. The method for preparing the superhydrophilic template stamp according to any one of claims 1 to 7, characterized in that, When preparing a nanoforest on one surface of a stamp substrate, the following steps are included: A substrate polymer layer is prepared on one surface of a stamp substrate; Plasma bombardment of the substrate polymer layer is used to form substrate polymer nanofibers. A nanoforest was fabricated on a stamp substrate by etching a stamp substrate using substrate polymer nanofibers as a mask. Remove the substrate polymer nanofibers.
9. The method for preparing the superhydrophilic template stamp according to claim 8, characterized in that, When bombarding the substrate polymer layer with plasma, the plasma used includes one or more combinations of oxygen plasma or carbon tetrafluoride plasma and argon plasma, helium plasma, nitrogen plasma or methane plasma.
10. The method for preparing the superhydrophilic template stamp according to claim 8, characterized in that, The substrate polymer layer includes PI.