Photocuring template process for preparing micron-sized structure
Through the photocuring template process, micron-scale structures are prepared by ultraviolet cross-linking of perfluoropolyether monomers and photoinitiators, which solves the flexibility and compatibility problems of preparing micron-scale structures in traditional photolithography technology and achieves efficient, repeatable pattern transfer and self-cleaning effects.
Patent Information
- Application Number
- CN202510813682.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-18
- Publication Date
- 2025-09-23
AI Technical Summary
Existing photolithography technology has problems such as high process costs, harsh preparation conditions, unsuitability for flexible substrate materials and non-reusability when preparing micron-level structures, and traditional solution stripping methods affect graphic accuracy and applicability.
The photocuring template process is adopted. A mixture of perfluoropolyether monomer and photoinitiator is cross-linked and cured under ultraviolet light. Combined with physical stripping and ultrasonic cleaning, a photocuring template with a micron-scale structure is prepared to achieve multiple pattern transfers and self-cleaning.
It improves the flexibility and compatibility of pattern transfer, has self-cleaning capabilities, can accurately control film thickness, is suitable for efficient pattern transfer of various materials on various substrates, and has a simple and reusable process.
Smart Images
Figure CN120690679A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of photolithography technology, and in particular relates to a photocuring template process for preparing a micron-level structure. Background Art
[0002] With the rapid advancement of new-generation information technology, the demand for high integration and miniaturization in electronic devices and systems is becoming increasingly urgent. Currently, the fabrication of microelectronic components relies heavily on traditional photolithography technology. Although photolithography can achieve nanoscale pattern transfer, it is constrained by its high process costs and demanding preparation conditions. It is important to note that the stripping of general photoresists requires a good solvent, acetone. However, most flexible polymer substrates, such as PDMS, PI, and PET, swell and deform in acetone solutions, inevitably affecting patterning accuracy. Furthermore, this solution-assisted stripping method is not suitable for pattern transfer of materials with poor substrate adhesion. Furthermore, a single photolithography pass can only achieve a single pattern transfer, making it impossible to separate the substrate from the substrate for molding and even more difficult to reuse. For micrometer-scale applications, whether flexible wearable electronics or microfluidic devices, a process solution that is more compatible with flexible substrates and more flexible and simple is urgently needed. Furthermore, with the development of 6G communications, research and development of terahertz (THz) frequency band technologies, between microwaves and visible light, is crucial. Metamaterials capable of efficiently manipulating THz waves have characteristic lengths on the micron scale. Dielectric metamaterials with high stability and low insertion loss also face significant challenges in fabrication and precision. In recent years, most dielectric metasurface fabrication has relied on etching of bulk silicon, a process that is not only limited by high process costs but also by small-scale production. Currently, compatible manufacturing technologies for emerging composite materials that also exhibit excellent electrical properties are immature, and structural precision is limited. The development of processes for micron-scale patterning holds great promise in the field of electronic science and technology.
[0003] Prepolymer monomers modified with specialized functional groups undergo cross-linking polymerization under the catalysis of a photoinitiator and in a UV environment. By patterning the exposed areas with a mask, this photocurable soft film can replicate complete micron-scale structures. In particular, the low surface energy of the photocurable soft film allows for easy physical peeling, while also possessing certain self-cleaning capabilities and mechanical strength. Furthermore, its film thickness can be precisely controlled, demonstrating significant potential for pattern transfer from a variety of materials onto a variety of substrates. Summary of the Invention
[0004] The purpose of the present invention is to address the problems existing in the background technology and propose a photocuring template process for preparing a micron-scale structure.
[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:
[0006] A photocuring template process for preparing a micron-scale structure comprises the following steps:
[0007] Step 1: Surface Preparation
[0008] After diluting perfluorodecyltriethoxysilane into a solution with a volume concentration of 1-2% using anhydrous ethanol, spray it evenly on the surface of the mask for oleophobic and hydrophobic treatment, and wait for it to dry naturally for use;
[0009] Step 2: Light Curing
[0010] A PFPE (perfluoropolyether) monomer and a 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator are mixed in a mass ratio of (9-19):1 and placed in a vacuum chamber to remove bubbles to obtain a curing solution. The curing solution is then dripped onto the surface of a silicon wafer, and the mask plate treated with oleophobic and hydrophobic materials in step 1 is pressed onto the dripped curing solution to evenly spread the solution. Finally, a 395nm UV curing lamp with a power of not less than 60W is turned on and the exposure is continued for 5-15 seconds to complete the cross-linking and curing process.
[0011] Step 3: Peel and Clean
[0012] Carefully transfer the PFPE membrane cured in step 2 to a beaker of anhydrous ethanol using tweezers and sonicate for at least 30 seconds.
[0013] Step 4: Template Transfer
[0014] Transfer the cleaned PFPE membrane from step 3 to a Petri dish filled with deionized water. When the PFPE membrane floats to the surface and unfolds naturally, remove it with a substrate sheet. After the water evaporates naturally, place it in an oven at 75-100°C for 30-60 minutes.
[0015] Step 5: Graphic Transfer
[0016] The patterned PFPE template on the substrate in step 4 can be used to achieve the pattern transfer function of various materials. After the transfer is completed, the PFPE film can be torn off with tweezers.
[0017] Furthermore, the PFPE monomer and the 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator in step 2 can be replaced by a photocurable film-forming prepolymer such as photocurable polyimide.
[0018] Furthermore, in step 2, before the curing liquid is dripped onto the surface of the silicon wafer, a ring-shaped gasket with a standard thickness can be placed on the silicon wafer, and then the curing liquid is dripped into the hollow area of the gasket and covered with the oleophobic and hydrophobic treated mask. Finally, an ultraviolet lamp is used to assist in cross-linking and curing to control the thickness of the formed PFPE film.
[0019] Furthermore, the substrate material in step 4 can be a rigid crystal such as silicon, silicon dioxide, aluminum oxide, etc., or a flexible polymer such as PDMS, PI, PET, etc.
[0020] Furthermore, the pattern transfer function of the multiple materials in step 5 can be thin film deposition, dielectric printing, nanoparticle self-assembly or ink spraying, etc.
[0021] Compared with the prior art, the present invention has the following beneficial effects:
[0022] 1. The present invention provides a photocurable template process for preparing micron-scale structures. Compared with traditional photolithography processes, the PFPE film can be physically removed rather than wet-peeled, greatly improving the flexibility of pattern transfer and compatibility with most materials.
[0023] 2. The present invention provides a photocurable template process for preparing a micron-scale structure, wherein the PFPE film has a certain self-cleaning ability and can be repeatedly transferred by multiple ultrasonic cleanings.
[0024] 3. The present invention provides a photocurable template process for preparing micron-scale structures. The thickness of the PFPE film can be precisely controlled by inserting a standard gasket, thereby realizing the transfer of columnar patterns with a certain thickness.
[0025] 4. The present invention provides a photocuring template process for preparing micron-level structures, which has a simple process flow, a large preparation area, and high repeatability. It is suitable for pattern transfer of various materials on various substrates with micron-level precision. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 A schematic diagram of a process flow for preparing a photocurable template with a micron-scale structure provided by the present invention;
[0027] Figure 2 These are photos of various materials after pattern transfer on various substrates in Example 1;
[0028] Figure 3 This is a photograph of the pattern transfer performed by repeatedly utilizing the PFPE film in Example 2. DETAILED DESCRIPTION
[0029] The technical solutions of the present invention are described in detail below with reference to the accompanying drawings and embodiments. It is apparent that the embodiments described are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.
[0030] Example 1
[0031] A 1% volume concentration of perfluorodecyltriethoxysilane in ethanol was sprayed onto the mask surface and allowed to dry naturally before use. 19g of PFPE monomer and 1g of 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator were mixed and stirred, then vacuumed to remove bubbles. Approximately 100μl of the mixture was then dropped onto a silicon wafer. The surface-treated mask was then pressed onto the mask. After 7s of UV exposure, the mask was peeled off and ultrasonically cleaned in anhydrous ethanol for 30s. Ten 10×10mm cleaned PFPE films were transferred to deionized water and removed from the substrates using silicon, quartz, PDMS, PI, and PET sheets, then dried in an oven at 100°C for 30min. The patterned templates on these substrates were then subjected to gold thin film sputtering, gold nanoparticle self-assembly, PDMS composite printing, and conductive ink spraying. Finally, the templates were peeled off.
[0032] Example 2
[0033] Spray a 1% volume concentration of perfluorodecyltriethoxysilane ethanol solution on the surface of the mask and dry it naturally for later use. Take 19g of PFPE monomer and 1g of 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator, mix and stir, then vacuum to remove bubbles, and then drop about 500μl on the silicon wafer. Press the surface-treated mask on it, and insert a 200μm thick gasket between the silicon wafer and the mask. After exposing it to UV light for 10s, peel it off and then put it into anhydrous ethanol for ultrasonic cleaning for 30s. Transfer 10 pieces of 10×10mm PFPE film washed to the deionized water surface, pick it out with PET sheet, dry it, and then dry it in an oven at 100℃ for 30min for later use.
[0034] First, a PDMS composite material was printed on a patterned PFPE film. After removing the PFPE film, a micron-scale cylindrical array of PDMS composite material on a PET substrate was obtained. The PDMS composite material was then transferred to beakers containing toluene, acetone, and alcohol and ultrasonically cleaned for 3 minutes. The cleaned PFPE film was then transferred to a deionized water surface, removed with a silicon wafer, air-dried, and then dried in a 100°C oven for 30 minutes before use.
[0035] Next, silver paste was printed on a patterned PFPE film. After removing the PFPE film, a circular array of silver film was formed on a silicon substrate. The film was then transferred to beakers containing toluene, acetone, and alcohol and ultrasonically cleaned for 3 minutes. The cleaned PFPE film was then transferred to a surface of deionized water, removed from the silicon wafer, air-dried, and then dried in a 100°C oven for 30 minutes before use.
[0036] Finally, a gold film is sputter-deposited on the patterned PFPE film, and the PFPE film is torn off to obtain a circular array of gold films on a silicon substrate.
[0037] Figure 1 This is a schematic diagram of a process flow for preparing a photocurable template with a micron-scale structure provided by the present invention.
[0038] Figure 2 These are photos of various materials after pattern transfer on various substrates in Example 1; Figure 2 As shown, circular arrays of gold and silver films were fabricated on silicon, quartz, and PDMS substrates. Circular arrays of conductive ink were transferred onto a PI substrate. Furthermore, micron-scale cylindrical arrays of PDMS composite materials were printed on a PET substrate. The designed circular arrays had radii of approximately 50, 100, and 200 μm, respectively, and periods of approximately 200, 400, and 800 μm, respectively. This demonstrates that PFPE templates not only facilitate the patterned transfer of thin films but also enable the printing of polymer slurry pillars of a certain height.
[0039] Figure 3 This is a photo of pattern transfer using the PFPE film repeatedly in Example 2; Figure 3 As shown, by utilizing the reusability and self-cleaning properties of PFPE membrane, the patterned transfer of PDMS composite material, silver film and gold film was completed three times on a quartz wafer and a silicon wafer respectively. The radius of the designed circular array is 100μm and the period is 400μm. For the micron-scale cylindrical array of PDMS composite material, its height is about 200μm.
[0040] The above description is only a preferred specific implementation method of the present invention and does not limit the present invention in any other form. Any technician familiar with the profession, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the protection scope of the present invention.
Claims
1. A photocuring template process for preparing micron-scale structures, characterized in that: The following steps are involved: Step 1: Surface Preparation After diluting perfluorodecyltriethoxysilane into a solution with a volume concentration of 1-2% using anhydrous ethanol, the solution is evenly sprayed on the surface of the mask for oleophobic and hydrophobic treatment, and then dried; Step 2: Light Curing PFPE monomer and 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator are mixed in a mass ratio of (9-19):1, placed in a vacuum chamber to remove bubbles, and a curing solution is obtained; the curing solution is then dropped onto the surface of a silicon wafer, and the mask plate treated with oleophobic and hydrophobic materials in step 1 is pressed onto the dripped curing solution to evenly spread it; finally, a 395nm UV curing lamp with a power of not less than 60W is turned on and the exposure is continued for 5-15 seconds to complete cross-linking and curing; Step 3: Peel and Clean Transfer the PFPE film cured in step 2 to a container containing anhydrous ethanol and sonicate for at least 30 seconds; Step 4: Template Transfer Transfer the cleaned PFPE membrane from step 3 to a container filled with deionized water. When the PFPE membrane floats to the surface and unfolds naturally, remove it with a substrate sheet. After the water evaporates naturally, place it in an oven at 75-100°C for 30-60 minutes. Step 5: Graphic Transfer The patterned PFPE template on the substrate in step 4 is used to achieve pattern transfer of various materials, and the PFPE film is removed after the transfer is completed.
2. The process for preparing a photocurable template of a micron-scale structure according to claim 1, characterized in that: The PFPE monomer and the 2-hydroxy-2-methyl-1-phenyl-1-propanone photoinitiator in step 2 are replaced by a photocurable film-forming prepolymer.
3. The process for preparing a photocurable template for a micron-scale structure according to claim 2, characterized in that: The photocurable film-forming prepolymer is photocurable polyimide.
4. The process for preparing a photocurable template for a micron-scale structure according to claim 1, characterized in that: In step 2, before the curing liquid is dripped onto the surface of the silicon wafer, a ring-shaped gasket is placed on the silicon wafer. Then, the curing liquid is dripped into the hollow area of the gasket and the mask plate treated with oleophobic and hydrophobic treatment is pressed on it. Finally, an ultraviolet lamp is used to assist in cross-linking and curing to control the thickness of the formed PFPE film.
5. The process for preparing a photocurable template for a micron-scale structure according to claim 1, characterized in that: The substrate sheet in step 4 is a rigid crystal or a flexible polymer.
6. The process for preparing a photocurable template for a micron-scale structure according to claim 5, characterized in that: The rigid crystal is silicon, silicon dioxide or aluminum oxide, and the flexible polymer is PDMS, PI or PET.
7. The process for preparing a photocurable template for a micron-scale structure according to claim 1, characterized in that: The pattern transfer method of the multiple materials in step 5 is thin film deposition, dielectric printing, nanoparticle self-assembly or ink spraying.