A method for preparing micro-nano structures on a polymer material

Abstract

The application discloses a method for preparing micro-nano structures on polymer materials, which comprises the following steps: firstly, preparing a polymer material film; secondly, self-assembling polystyrene (PS) small balls on a water-air interface; thirdly, preparing a PS micro-ball film and sticking the PS micro-ball film to the polymer material film; and finally, etching the polymer material film by using oxygen plasma to form micro-nano structures, placing the dried polymer material film in an etching machine, setting etching power and oxygen flow, and adjusting etching time to control the depth of the micro-nano structures; changing the diameter of the PS small balls to control the size of the micro-nano structures; and using different polymer material films to control the morphology of the micro-nano structures.

Description

Technical Field

[0001] This invention belongs to the field of micro-nano manufacturing technology, specifically relating to a method for preparing micro-nano structures on polymer materials. Background Technology

[0002] Micro- and nanostructures are structures in the micrometer and nanometer scale range. Their small-scale effects, surface effects, interface effects, and quantum effects give them unique properties in optics, electricity, and magnetism. Therefore, micro- and nanostructures have wide applications in many fields.

[0003] With the increasing demand for micro and nanostructures, engineers in related fields have developed many methods for fabricating them. Among them, photolithography, as a traditional micro and nanostructure fabrication technology, has the characteristics of large-scale mass production and simple operation steps. However, photolithography has relatively stringent requirements for equipment, processing environment, process flow, and instrument maintenance, and can only fabricate microstructures on a limited number of materials such as photoresists, semiconductors, and metals.

[0004] Polymer materials are widely used in many fields due to their advantages such as micro / nano-scale molecular chain structure, stable and controllable synthesis reactions, simple and low-cost processing, and diverse functions. Polymer materials exhibit excellent performance in the fabrication of micro / nano-scale patterned structures. By selecting different polymer materials and processing techniques, microstructures with different morphologies, sizes, and special functions can be prepared. Currently, many polymer-based microstructure processing technologies have emerged, such as nanoimprinting, flexible printing, and vacuum freeze-drying. However, these technologies require high-cost equipment, have high requirements for the materials being processed, and face some challenges and limitations in practical applications, necessitating further improvements. Summary of the Invention

[0005] This invention provides a method for preparing micro-nano structures on polymer materials, and designs a low-cost, simple-to-fabricate, and controllable method for preparing micro-nano structures on polymer materials.

[0006] To solve the above problems, the technical solution provided by the present invention is as follows:

[0007] This invention provides a method for preparing micro / nano structures on polymer materials, comprising the following steps:

[0008] Step 1, Preparation of polymer material film substrate: The polymer material film is cut into a square structure of a preset size and ultrasonically cleaned with anhydrous ethanol. After drying, the polymer material film is hydrophilically treated with an air plasma cleaner to facilitate the subsequent adhesion of PS microspheres.

[0009] Step 2, preparation of PS microsphere film: select monodisperse PS solution with uniform particle size and less impurities, centrifuge the appropriate amount of monodisperse PS microsphere solution using a centrifuge, remove the supernatant after centrifugation, then add an equal amount of anhydrous ethanol, mix evenly; use deionized water to prepare SDS solution for subsequent self-assembly of PS microspheres; pour an appropriate amount of deionized water into the vessel, then use a microsyringe to slowly add the PS solution with anhydrous ethanol close to the water surface of the vessel onto the water surface, and a scattered PS microsphere film will appear on the liquid surface in the vessel; then use a microsyringe to slowly add a small amount of SDS solution into the vessel, and the scattered PS microsphere film will be gathered together under the action of SDS to form a complete and dense film.

[0010] Step 3, use the polymer material film to stick the PS microsphere film that has been formed from above the liquid surface of the vessel, and naturally air dry.

[0011] Step 4, etch the polymer material film with oxygen plasma to form a micro-nano structure, place the air-dried polymer material film in the etching machine, set the etching power and oxygen flow, adjust the etching time to control the depth of the micro-nano structure, and if a pure polymer material film micro-nano structure is needed, the PS microspheres can be peeled off.

[0012] According to an optional embodiment of the present application, step S1 specifically includes: preparing PI and PET films, cutting them into 1cm x 1cm size, and ultrasonically cleaning the cut films with anhydrous ethanol for 5min; after drying, use an air plasma cleaning machine to perform hydrophilic treatment on the films, and the cleaning time and power of the hydrophilic treatment are 30s and 100W respectively.

[0013] According to an optional embodiment of the present application, step S2 specifically includes: centrifuge 1ml of 10um, 2.5wt% concentration PS microsphere solution in a centrifuge, and the centrifugation time and speed are 5min and 7000r / min respectively; remove the supernatant after centrifugation, add 1ml of anhydrous ethanol, and shake evenly; use deionized water to prepare a 5wt% SDS solution; pour 3 / 4 deionized water into the vessel, then use a microsyringe to slowly add the PS solution with anhydrous ethanol close to the water surface onto the water surface, and a scattered PS microsphere film will form on the water surface; then use a microsyringe to slowly add 2ul of SDS solution into the vessel, and the scattered PS microsphere film will gather together under the action of SDS to form a complete and dense film.

[0014] According to an optional embodiment of the present application, step 3 specifically comprises: using PI and PET films respectively to stick the PS microsphere film which has been formed from above the liquid surface of the vessel, and finally naturally air-drying; and step 4 specifically comprises: placing the air-dried PI and PET films in an etching machine, and setting the etching power, oxygen flow and etching time respectively as 200W, 300sccm and 1h.

[0015] According to an optional embodiment of the present application, step S1 specifically comprises: preparing a PET material film, cutting it into a size of 1cm*1cm, and ultrasonically cleaning it with anhydrous ethanol for 5min; after drying, using an air plasma cleaning machine to perform hydrophilic treatment on the film, and setting the cleaning time and power of the hydrophilic treatment respectively as 30s and 100W.

[0016] According to an optional embodiment of the present application, step S2 specifically comprises: taking 1ml of PS microsphere solution with particle sizes of 2um / 5um / 10um and a concentration of 2.5wt%, and placing it in a centrifuge to centrifuge, at a centrifugal speed of 7000r / min, for 10min / 7min / 5min respectively; removing the supernatant after centrifugation, adding 1ml of anhydrous ethanol, and shaking uniformly; using deionized water to configure a 5wt% SDS solution; pouring 3 / 4 deionized water into a vessel, and then using a microsyringe to slowly drop 2ul of the 2um PS solution added with anhydrous ethanol onto the water surface, so that a scattered PS microsphere film is formed on the water surface; and then using the microsyringe to slowly drop 2ul of the SDS solution into the vessel, so that the scattered PS microsphere film is gathered together under the action of the SDS to form a complete and dense film.

[0017] According to an optional embodiment of the present application, the “2um PS solution added with anhydrous ethanol” in step S2 is replaced with “5um and 10um PS solutions added with anhydrous ethanol”, and the steps of step S2 are repeated.

[0018] According to an optional embodiment of the present application, step 3 specifically comprises: using a PET film to stick the PS microsphere film which has been formed from above the liquid surface of the vessel, and finally naturally air-drying; and step 4 specifically comprises: placing the air-dried PET film in an etching machine, and setting the etching power and oxygen flow as 200W and 300sccm, and setting the etching time respectively as 20min, 40min and 1h.

[0019] Beneficial effects: the method for preparing micro-nano structure on polymer material provided by the embodiment of the application firstly prepares a polymer material film, then self-assembles polystyrene PS small balls at a water-air interface, then prepares a PS micro-ball film, and then sticks the PS micro-ball film with the polymer material film; finally, the polymer material film after air drying is placed in an etching machine, the power and oxygen flow of etching are set, and the etching time is adjusted to control the depth of the micro-nano structure; the diameter of the PS small balls is changed to control the size of the micro-nano structure; different polymer material films are used to control the morphology of the micro-nano structure; therefore, the micro-nano structure on the polymer material can be prepared simply and at low cost, and the size, morphology and depth of the micro-nano structure can be controlled. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0021] Figure 1 The flow chart of the method for preparing micro-nano structure on polymer material provided by the embodiment of the application.

[0022] Figure 2 The structural schematic diagram of the method for preparing micro-nano structure on polymer material provided by the embodiment of the application.

[0023] Figure 3 The schematic diagram of the influence of different polymer materials on the morphology of micro-nano structure in embodiment 1.

[0024] Figure 4 The schematic diagram of the size of micro-nano structure formed by using PS small balls with different particle sizes in embodiment 2.

[0025] Figure 5 The schematic diagram of the microstructure formed on the PET film under different etching times in embodiment 3. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0027] As Figure 1As shown, this embodiment of the invention provides a method for preparing micro / nano structures on polymer materials, comprising the following steps:

[0028] Step 1, Preparation of polymer material film substrate: The polymer material film is cut into a square structure of a preset size and ultrasonically cleaned with anhydrous ethanol. After drying, the polymer material film is hydrophilically treated with an air plasma cleaner to facilitate the subsequent adhesion of PS microspheres.

[0029] Step 2, Preparation of PS microsphere film: Select a monodisperse PS solution with uniform particle size and few impurities. Centrifuge an appropriate amount of monodisperse PS microsphere solution using a centrifuge. After centrifugation, remove the supernatant and add an equal amount of anhydrous ethanol, then mix thoroughly. Prepare SDS solution using deionized water for subsequent self-assembly of PS microspheres. Pour an appropriate amount of deionized water into a container, and then use a microsyringe to slowly drop the PS solution with added anhydrous ethanol close to the water surface of the container. Scattered PS microsphere films will appear on the liquid surface in the container. Then, use a microsyringe to slowly add a small amount of SDS solution into the container. The scattered PS microsphere films will aggregate together under the action of SDS to form a complete and dense film.

[0030] Step 3: Use a polymer material film to pick up the PS microsphere film that has been formed from above the liquid surface of the container, and let it air dry naturally.

[0031] Step 4: Use oxygen plasma to etch the polymer material film to form a micro / nano structure. Place the dried polymer material film in the etching machine, set the etching power and oxygen flow rate, and adjust the etching time to control the depth of the micro / nano structure. If a micro / nano structure of pure polymer material film is required, PS microspheres can be peeled off.

[0032] In this embodiment, the PS material is polystyrene, the SDS material is sodium dodecyl sulfate, and the polymer film is polyimide (PI) and / or polyethylene terephthalate (PET). The type of material affects the morphology of the final micro / nano structure. PS microspheres on the PI film gradually shrink during etching, while PS microspheres on the PET film react with the PET during etching, resulting in pit formation. Ultimately, the PS microspheres can be peeled off or left as part of the micro / nano structure.

[0033] like Figure 2 As shown, in steps 1 to 4, a substrate is prepared, a clean square polymer film is prepared, a polystyrene (PS) microsphere film is prepared, PS microspheres are self-assembled at the water-air interface and bonded to the substrate, and oxygen plasma etching is performed. The above steps can easily and cost-effectively prepare micro-nano structures on polymer materials. The size, morphology, and depth of the micro-nano structures can be controlled. The size of the final micro-nano structure can be controlled by changing the particle size of the PS microspheres.

[0034] Example 1

[0035] A method for preparing micro / nano structures on polymer materials specifically includes the following steps:

[0036] Step S1 specifically includes: preparing PI and PET films, cutting them into 1cm×1cm sizes, and ultrasonically cleaning the cut films with anhydrous ethanol for 5 minutes; after drying, using an air plasma cleaner to perform hydrophilic treatment on the films, with cleaning time and power of 30s and 100W respectively.

[0037] Step S2 specifically includes: taking 1 ml of 10 μm, 2.5 wt% PS microsphere solution and centrifuging it in a centrifuge for 5 min and 7000 r / min; removing the supernatant after centrifugation, adding 1 ml of anhydrous ethanol, and shaking well; preparing a 5 wt% SDS solution using deionized water; pouring 3 / 4 of the deionized water into a container, and then using a microsyringe to slowly drip the PS solution with added anhydrous ethanol close to the water surface, which will form a scattered PS microsphere film on the water surface; then using a microsyringe to slowly add 2 μl of SDS solution into the container, and under the action of SDS, the scattered PS microsphere film aggregates together to form a complete and dense film.

[0038] Step 3 specifically includes: using PI and PET films respectively to pick up the PS microsphere film that has been formed from above the liquid surface of the container, and finally letting it air dry naturally; Step 4 specifically includes: placing the dried PI and PET films in the etching machine, and setting the etching power, oxygen flow rate and etching time to 200W, 300sccm and 1h respectively.

[0039] like Figure 3 As shown, adjusting the choice of polymer material film can alter the morphology of the final micro / nano structure. Figure 3 (a) is a schematic diagram of the formation of micro / nano structures on a PI film. Figure 3 (b) is a schematic diagram of the micro-nano structure formed on the PET film.

[0040] Example 2

[0041] A method for preparing micro / nano structures on polymer materials specifically includes the following steps:

[0042] Step S1 specifically includes: preparing a PET film, cutting it into 1cm×1cm sizes, and ultrasonically cleaning it with anhydrous ethanol for 5 minutes; after drying, using an air plasma cleaner to perform hydrophilic treatment on the film, with cleaning time and power of 30s and 100W respectively.

[0043] Step S2 specifically includes: taking 1 ml of PS microsphere solutions with particle sizes of 2 μm / 5 μm / 10 μm and a concentration of 2.5 wt% and centrifuging them in a centrifuge at a speed of 7000 r / min for 10 min / 7 min / 5 min respectively; removing the supernatant after centrifugation, adding 1 ml of anhydrous ethanol, and shaking well; preparing a 5 wt% SDS solution using deionized water; pouring 3 / 4 of the deionized water into a container, and then using a microsyringe to slowly drop the 2 μm PS solution with added anhydrous ethanol close to the water surface, which will form a scattered PS microsphere film on the water surface; then using a microsyringe to slowly add 2 μl of SDS solution into the container, and under the action of SDS, the scattered PS microsphere film aggregates together to form a complete and dense film.

[0044] Step 3 specifically includes: using a PET film to pick up the PS microsphere film that has been formed from above the liquid surface of the container, and finally letting it air dry naturally; Step 4 specifically includes: placing the dried PI and PET films in the etching machine, and setting the etching power, oxygen flow rate and etching time.

[0045] Example 2 further includes replacing "2µm PS solution with anhydrous ethanol" in step S2 with "5µm and 10µm PS solutions with anhydrous ethanol", and repeating steps S2 and S3.

[0046] In Example 2, step 3 specifically includes: using a PET film to pick up the PS microsphere film that has been formed from above the liquid surface of the container, and finally letting it air dry naturally; step 4 specifically includes: placing the dried PET film in an etching machine, with etching power and oxygen flow rate of 200W and 300sccm, and etching times of 20min, 40min, and 1h respectively.

[0047] like Figure 4 As shown, by changing the particle size of PS microspheres to control the size of the final micro / nano structure, it can be found that the size of the final micro / nano structure is positively correlated with the particle size of the selected PS. Figure 4 (a) Schematic diagram of a micro / nano structure formed using PS microspheres with a particle size of 2 μm. Figure 4 (b) is a schematic diagram of a micro / nano structure formed using PS microspheres with a particle size of 10 μm.

[0048] Example 3

[0049] A method for preparing micro / nano structures on polymer materials specifically includes the following steps:

[0050] The step S1 specifically comprises: preparing a PET material film, cutting into 1cm*1cm size, and cleaning with anhydrous ethanol for 5 minutes by ultrasonic; after drying, the film is subjected to hydrophilic treatment by using an air plasma cleaning machine, and the cleaning time and power of the hydrophilic treatment are 30 seconds and 100 W respectively.

[0051] The step S2 specifically comprises: taking 1ml of PS microsphere solution with particle sizes of 2um / 5um / 10um and a concentration of 2.5wt% into a centrifuge, and centrifuging at a centrifugal speed of 7000r / min for 10min / 7min / 5min respectively; removing the supernatant after centrifugation, adding 1ml of anhydrous ethanol, and shaking uniformly; using deionized water to prepare a 5wt% SDS solution; pouring 3 / 4 deionized water into a vessel, and then slowly adding the 2um PS solution with anhydrous ethanol close to the water surface by using a microsyringe, so that a scattered PS microsphere film is formed on the water surface; and then slowly adding 2ul of the SDS solution into the vessel by using a microsyringe, so that the scattered PS microsphere film is gathered together to form a complete and dense film under the action of the SDS.

[0052] The step 3 specifically comprises: using the PET film to stick the formed PS microsphere film from above the liquid surface of the vessel, and finally naturally drying; and the step 4 specifically comprises: placing the dried PET film in an etching machine, and setting the etching power and oxygen flow to be 200W and 300sccm respectively, and setting the etching time to be 20min, 40min and 1h respectively.

[0053] As shown in Figure 5 , the depth of the micro-nano structure is controlled by adjusting the etching time, and the microstructure formed on the PET film under different etching times. Figure 5 Fig. 1(a) is a schematic view of the microstructure formed by the etching time of 20min, Figure 5 Fig. 1(b) is a schematic view of the microstructure formed by the etching time of 40min, Figure 5 Fig. 1(c) is a schematic view of the microstructure formed by the etching time of 1h.

[0054] The above merely describes specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any modification, equivalent replacement and improvement made by any person skilled in the art within the technical range disclosed by the present application, as long as it is within the spirit and principle of the present application, should be covered within the protection scope of the present application; any person skilled in the art can make various changes and decorations without departing from the spirit and scope of the present application, therefore the protection scope of the present application is defined by the scope of the claims.

Claims

1. A method for fabricating micro- and nano-structures on a polymer material, characterized in that, Comprise the following steps: Step 1, preparation of polymer material film base: the polymer material film is cut into a square structure of a predetermined size, and is ultrasonically cleaned with anhydrous ethanol, and after drying, the polymer material film is subjected to hydrophilic treatment using an air plasma cleaning machine, to facilitate subsequent adhesion of the PS microspheres; Step 2, preparation of PS microsphere film: a monodisperse PS solution with uniform particle size and few impurities is selected, and an appropriate amount of the monodisperse PS microsphere solution is subjected to centrifugation using a centrifuge, and after centrifugation, the supernatant is removed, and then an equal amount of anhydrous ethanol is added and mixed uniformly; a SDS solution is prepared using deionized water, for subsequent self-assembly of the PS microspheres; an appropriate amount of deionized water is poured into a vessel, and then the PS solution with anhydrous ethanol added is slowly added to the water surface using a microsyringe, and a scattered PS microsphere film will appear on the liquid surface in the vessel; a small amount of the SDS solution is slowly added to the vessel using a microsyringe, and the scattered PS microsphere film will gather together under the action of the SDS to form a complete and dense film; the PS material is polystyrene, the SDS material is sodium dodecyl sulfate, and the polymer material film is polyimide PI and / or polyethylene terephthalate PET; Step 3, the polymer material film is used to adhere the formed PS microsphere film from above the liquid surface of the vessel, and is naturally air-dried; Step 4, the polymer material film is etched using oxygen plasma to form a micro-nano structure, the air-dried polymer material film is placed in an etching machine, the etching power and oxygen flow rate are set, and the etching time is adjusted to control the depth of the micro-nano structure, and if a pure polymer material film micro-nano structure is required, the PS microspheres can be peeled off; Step S1 specifically comprises: preparing PI and PET films, cutting them into 1cm x 1cm squares, and ultrasonically cleaning the cut films with anhydrous ethanol for 5min; after drying, the films are subjected to hydrophilic treatment using an air plasma cleaning machine, and the hydrophilic treatment cleaning time and power are 30s and 100W, respectively; Step S2 specifically comprises: taking 1ml of a 10 micron, 2.5wt% PS microsphere solution and placing it in a centrifuge, and the centrifugation time and speed are 5min and 7000r / min, respectively; removing the supernatant after centrifugation, adding 1ml of anhydrous ethanol, and shaking uniformly; preparing a 5wt% SDS solution using deionized water; pouring 3 / 4 deionized water into a vessel, and then slowly adding the PS solution with anhydrous ethanol added to the water surface using a microsyringe, and a scattered PS microsphere film will form on the water surface; slowly adding 2 microliters of the SDS solution to the vessel using a microsyringe, and the scattered PS microsphere film will gather together under the action of the SDS to form a complete and dense film; Step 3 specifically comprises: using PI and PET films to adhere the formed PS microsphere film from above the liquid surface of the vessel, and finally air-drying; Step 4 specifically comprises: placing the air-dried PI and PET films in an etching machine, and setting the etching power, oxygen flow rate, and etching time to be 200W, 300sccm, and 1h, respectively.

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