Hexagonal non-close-packed gold particle array based on microscopically complex surface and its preparation method

Abstract

The present invention belongs to the field of micro-nano optical materials technology, specifically relating to a hexagonal, non-close-packed gold nanoparticle array based on a microscopically complex surface and a method for preparing the same. The preparation method is primarily based on a colloidal crystal template calcination method and comprises: filling the microscopically complex surface with UV-curable adhesive and curing it; assembling a monolayer of polystyrene microspheres using a gas-liquid interface self-assembly method and transferring them to a target surface; and sputtering a monolayer of elemental gold and calcining it to produce a hexagonal, non-close-packed gold nanoparticle array with a well-symmetric microscopically complex surface. The non-close-packed gold nanoparticle array prepared by the present invention not only exhibits good periodicity and substrate conformability, but also has an additional step compared to the traditional colloidal crystal template calcination method, resulting in simpler operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of micro-nano optical materials, and in particular relates to a hexagonal non-close-packed gold particle array with a microscopic complex surface and a preparation method thereof. Background Art

[0002] When noble metal nanostructure units are arranged in a regular periodic pattern, far-field coupling between the particles can occur, generating a lattice resonance phenomenon known as plasmon lattice resonance (SLR). For example, when gold nanoparticles are arranged with a typical 500-nanometer periodicity, their free electrons strongly absorb incident light of a specific wavelength, generating a collective electron resonance. This surface lattice resonance (SLR) absorption peak is observed in the absorption spectrum. This absorption peak is extremely sensitive and has an ultra-high quality factor, making it of great value in sensing and monitoring applications.

[0003] At present, the traditional preparation methods of non-close-packed gold nanoparticle lattices, such as template shadow mask and colloidal crystal template calcination, are limited to the two-dimensional rigid plane. Compared with the three-dimensional lattice, the control factor of this lattice is missing a dimension. The existing technology relies on the two-dimensional rigid plane when preparing the array, lacks the spatial control dimension, and the obtained two-dimensional planar gold particle array has a single morphology and limited application scenarios. At present, there are reports that the lattice with good periodicity can be transferred conformally by thermal reflow transfer, but the array prepared by this transfer method has problems such as the pattern and the substrate are not firmly bonded, there is a certain periodic quality loss in the transfer process, and the lattice preparation and patterning cannot be synchronized.

[0004] Therefore, developing a stable synchronous preparation method to prepare gold nanoparticle arrays that are firmly adhered to microscopic high-curvature surfaces has important scientific and industrial significance and can expand the application scenarios of non-close-packed gold nanoparticle arrays. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing colloidal crystal template calcination preparation technology for microscopically complex surfaces and provide a simple high-fidelity preparation method for hexagonal non-close-packed gold nanoparticle arrays based on microscopically complex surfaces.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, comprising the following steps:

[0007] S1. Spin-coating a curing adhesive onto a substrate with a microscopically complex surface to make the substrate filled and flat, and curing the spin-coated curing adhesive to obtain a cured adhesive layer;

[0008] S2, placing the substrate with the cured adhesive layer under an oxygen plasma cleaning machine to prepare a hydrophilic surface on the cured adhesive layer;

[0009] S3, assembling a monolayer of hexagonally close-packed polystyrene microspheres on a hydrophilic surface using a gas-liquid interface self-assembly method, wherein the diameter of the polystyrene microspheres is 200-2000 nm, to form a polystyrene microsphere film;

[0010] S4. A gold film with a thickness of 10-200 nm is sputtered on the polystyrene microsphere film using a magnetron sputtering apparatus, and then calcined at 500-1300°C for 0.5-8 hours to obtain a hexagonal non-close-packed gold particle array based on a microscopically complex surface.

[0011] As a further improvement of the preparation method of hexagonal non-close-packed gold particle arrays based on microscopic complex surfaces:

[0012] Preferably, the curing adhesive in step S1 is a UV curing adhesive of model Norland NOA 61.

[0013] Preferably, the UV curing adhesive is spin-coated on the substrate at a speed of 500-10,000 rpm for 10-300 s, and then placed under a UV lamp for irradiation curing.

[0014] Preferably, the ultraviolet lamp is an LED ultraviolet UV curing lamp produced by Tiandou Lighting Appliance Factory in Henglan Town, Zhongshan City, model AC85-260V, with a wavelength of 365nm and a power of 35w.

[0015] Preferably, the oxygen plasma cleaning machine in step S2 is a model TS-SYPL05 product of Shenzhen Eastcom High-Tech Automation Equipment Co., Ltd., with a power of 15-300W, an oxygen flow rate of 1-600mL / min, and a cleaning time of 20-1000s.

[0016] Preferably, the gas-liquid interface self-assembly method in step S3 is specifically as follows:

[0017] 1) Take <100> The monocrystalline silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water in sequence, drying it, and then cleaning it with oxygen plasma.

[0018] 2) preparing a polystyrene microsphere dispersion having a concentration of 0.5-10 wt % and a diameter of 200-2000 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and sonicating for 1-30 minutes to obtain a polystyrene microsphere solution;

[0019] 3) adding 2-12 mL of deionized water to the hydrophilic surface of the single crystal silicon wafer, adding a polystyrene microsphere solution along the edge of the single crystal silicon wafer, and then adding 5-50 μL of a 0.1-5 mol / L sodium dodecyl sulfate solution (SDS solution) along the edge of the single crystal silicon wafer to self-assemble into a monolayer polystyrene microsphere array on the single crystal silicon wafer;

[0020] 4) adding 30 μL to 500 μL of a 0.1-5 mol / L SDS solution dropwise to 1 L of water, immersing the single-crystalline silicon wafer having the monolayer polystyrene microsphere array in the water, with the monolayer polystyrene microsphere array floating on the water surface; immersing the substrate with the hydrophilic surface facing upward in water, transferring the monolayer polystyrene microsphere array to the hydrophilic surface, and removing the substrate, thereby producing a polystyrene microsphere film on the substrate.

[0021] A second object of the present invention is to provide a hexagonal non-close-packed gold particle array based on a microscopically complex surface obtained by any of the preparation methods described above.

[0022] The beneficial effects of the present invention compared to the prior art are:

[0023] 1) The present invention provides a method for preparing a hexagonal non-close-packed gold nanoparticle array based on a microscopically complex surface, wherein a curing adhesive is used to fill and flatten a complex surface having curvature or microscopic non-conductive surfaces, and a curing post-treatment is performed to obtain a cured adhesive layer; the microscopically complex surface includes but is not limited to a microsphere array, a pyramid array, and may also be other forms of non-planar surfaces; the curing adhesive covers and fills the gaps and discontinuities on the complex surface to form a continuous plane so that the spatial arrangement of the polystyrene microspheres is not affected by the microscopically complex surface;

[0024] The surface of the cured adhesive layer is cleaned with oxygen plasma to increase the content of hydroxyl groups on the interface of the cured adhesive layer and make the cured adhesive layer hydrophilic, so that the polystyrene microsphere film can be firmly attached to the cured adhesive layer.

[0025] A single-layer polystyrene microsphere template is transferred on a hydrophilic surface, preferably with a polystyrene microsphere of 500 nm in diameter, so that the period of the hexagonal non-close-packed gold particle array based on the microscopic complex surface formed after subsequent calcination is 500 nm, so as to produce a strong plasmon resonance effect; when self-assembling the polystyrene microspheres, water is first dripped on the hydrophilic surface of the single-crystalline silicon wafer, and then a sodium dodecyl sulfate solution, i.e., SDS solution, is dripped along the edge of the single-crystalline silicon wafer. The SDS solution is used to control the gas-liquid interfacial tension, forcing the gas-liquid interface gaps between the polystyrene microspheres to be greatly reduced, thereby forming a relatively dense single-layer polystyrene microsphere array; dripping the SDS solution into the water can control the liquid surface tension to be greater than the surface tension of the single-crystalline silicon wafer, thereby preventing the dissociation of the polystyrene microsphere array caused by excessive surface tension of the single-crystalline silicon wafer; so that the polystyrene microsphere array remains in a hexagonal close-packed state after transfer;

[0026] By using the colloidal crystal template calcination method, a single layer of gold is sputtered on it and then calcined to prepare hexagonal non-close-packed gold particle arrays based on microscopic complex surfaces, which greatly broadens the application range of plasmonic nanomaterials. For example, hexagonal non-close-packed gold nanoparticle arrays can be prepared on spheres with a radius in the micron range, on microscopic pyramids, and on microscopic irregular surfaces.

[0027] 2) The hexagonal non-close-packed gold particle arrays produced by the present invention can firmly adhere to microscopic surfaces with medium to high curvature and microscopic non-conductive surfaces, such as the surfaces of 5μm and 10μm diameter SiO2 microspheres and microscopic pyramid arrays, while maintaining the hexagonal non-close-packed spatial arrangement of the gold particles. The spacing between the gold particles along the surface remains the same as the diameter of the polystyrene microspheres, effectively maintaining the spatial spacing characteristics of their planar arrangement. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 The present invention is a flow chart of a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface.

[0030] Figure 2 is a cross-sectional electron microscope image of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 1 of the present invention;

[0031] Figure 3 This is an electron microscope image of a hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared in Example 1 of the present invention;

[0032] Figure 4 is a cross-sectional electron micrograph of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 2 of the present invention;

[0033] Figure 5 This is an electron microscope image of a hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared in Example 2 of the present invention;

[0034] Figure 6 is an electron microscope image of a cross section of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 3 of the present invention;

[0035] Figure 7 This is an electron microscope image of a hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared in Example 3 of the present invention;

[0036] Figure 8 is a cross-sectional electron micrograph of a SiO2 microsphere array with a diameter of 5 μm produced on a single crystal silicon wafer in Example 4 of the present invention;

[0037] Figure 9 This is a cross-sectional electron micrograph of a 5 μm diameter SiO2 microsphere array coated with UV-curable adhesive in Example 4 of the present invention;

[0038] Figure 10 is a cross-sectional electron micrograph of a square silicon wafer after gold film is sputtered on a polystyrene microsphere film in Example 4 of the present invention;

[0039] Figure 11 This is a plan view electron microscope image of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 4 of the present invention;

[0040] Figure 12 This is an electron microscope image of a hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared in Example 4 of the present invention;

[0041] Figure 13 is a cross-sectional electron micrograph of a SiO2 microsphere array with a diameter of 10 μm produced on a single crystal silicon wafer in Example 5 of the present invention;

[0042] Figure 14 This is a cross-sectional electron micrograph of a 10 μm diameter SiO2 microsphere array coated with UV-curable adhesive in Example 5 of the present invention;

[0043] Figure 15 This is an electron microscope image of a cross section of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 5 of the present invention;

[0044] Figure 16 This is a plan view electron microscope image of a square silicon wafer after a gold film is sputtered on a polystyrene microsphere film in Example 5 of the present invention;

[0045] Figure 17 This is an electron microscope image of a hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared in Example 5 of the present invention. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] The following describes in detail the microscopic complex surface hexagonal non-close-packed gold nanoparticle array and its preparation method in the present invention.

[0048] First, the Quorum Q150RS Plus magnetron sputtering instrument used in the present invention, the AC85-260V LED UV curing lamp from Tiandou Lighting Appliance Factory in Henglan Town, Zhongshan City, and the plasma cleaning machine model TS-SYPL05 from Shenzhen Eastcom High-Tech Automation Equipment Co., Ltd. were purchased from the market. <100> A 4-inch single crystal silicon wafer, ethanol (CH3CH2OH), acetone (CH3COCH3), a polystyrene microsphere dispersion (500 nm diameter, 2.5% aqueous dispersion), Norland NOA 61 UV-curable adhesive, and polydimethylsiloxane (PDMS) were prepared; the polystyrene microsphere dispersion, ethanol, and acetone were mixed in a volume ratio of 2:1:1 and ultrasonicated to prepare a polystyrene microsphere solution.

[0049] The present invention will be further described in detail below with reference to specific implementation examples, but the present invention is not limited to the specific examples listed below.

[0050] Example 1

[0051] This embodiment provides a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, based on a SiO2 microsphere array with a diameter of 5 μm. The preparation process is as follows: Figure 1 As shown, the specific steps include:

[0052] S1. Preparation of substrates with microscopically complex surfaces:

[0053] (a) Pour polydimethylsiloxane (PDMS) and curing liquid into a Petri dish and mix them. After the bubbles dissipate, place it at 60°C to cure for 2 hours. Then, pour a small amount of 5μm diameter SiO2 microsphere powder on it and spread it evenly with a hard object to evenly distribute the SiO2 microsphere powder on the surface.

[0054] (b) Cut the single crystal silicon wafer into 1cm 2 A square silicon wafer is spin-coated with Norland NOA 61 UV curing adhesive at a speed of 10,000 rpm for 1 minute; the side of the single crystal silicon wafer spin-coated with the UV curing adhesive is placed on the side where the SiO2 microsphere powder is located in step (a), and the mixture is irradiated with a 365 nm wavelength, 35 W power UV lamp for at least 1 minute to cure the mixture, and then the square silicon wafer is torn off, i.e., the SiO2 microsphere powder is transferred to the square silicon wafer to serve as a substrate with a microscopically complex surface;

[0055] S2. Spin-coat a layer of Norland NOA 61 UV-curing adhesive on the microscopically complex surface of the substrate at a spin-coating speed of 2000-10000 rpm for 200 s until the surface is evenly filled. Irradiate the UV-curing adhesive with a UV lamp at a wavelength of 365 nm and a power of 35 W for 30 s to cure the adhesive layer.

[0056] S3, placing the cured adhesive layer under an oxygen plasma cleaning machine with a power of 15W and an oxygen flow rate of 10mL / min to obtain a hydrophilic surface on the cured adhesive layer of the substrate;

[0057] S4. Assemble a polystyrene microsphere film on a hydrophilic surface using the air-liquid interface self-assembly method. The detailed steps are as follows:

[0058] Step 1), take <100> A 4-inch single-crystal silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water, drying it, and then cleaning it with oxygen plasma.

[0059] Step 2), preparing a polystyrene microsphere dispersion with a concentration of 2.5 wt% and a diameter of 500 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and ultrasonicating for 5 minutes to obtain a polystyrene microsphere solution;

[0060] 8 mL of deionized water was first added to the hydrophilic surface of a single-crystal silicon wafer. A polystyrene microsphere solution was then added along the edge of the single-crystal silicon wafer. Finally, 10 μL of a 0.1 mol / L SDS solution was added along the edge of the single-crystal silicon wafer. The SDS solution filled the gaps between the polystyrene microspheres, forming a single-layer polystyrene microsphere array on the single-crystal silicon wafer.

[0061] Step 3) adding 50 μL of 1 mol / L sodium dodecyl sulfate solution (SDS solution) to 1 L of water, immersing the single crystal silicon wafer with the monolayer polystyrene microsphere array in the water, and the monolayer polystyrene microsphere array floats on the water surface;

[0062] Step 4), immersing the substrate in step S3 in water with the hydrophilic surface of the cured adhesive layer facing upward, and scooping up the single-layer polystyrene microsphere array from below the liquid surface, and transferring the single-layer polystyrene microsphere array to the hydrophilic surface, thereby preparing a polystyrene microsphere film on the cured adhesive layer of the substrate;

[0063] S5, the substrate of the prepared polystyrene microsphere film was placed in a Quorum Q150RS Plus magnetron sputtering instrument, and a gold film was sputtered on the polystyrene microsphere film at a current of 20 mA for 200 s to a thickness of 50 nm. Figure 2 composite product of

[0064] S6. Place the square silicon wafer with the gold film sputtered into a calcining furnace and calcine it at 1050°C for 3 hours to obtain a hexagonal non-close-packed gold particle array based on a microscopically complex surface. Figure 3 shown.

[0065] Example 2

[0066] This embodiment provides a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, based on a SiO2 microsphere array with a diameter of 10 μm. The preparation process is as follows: Figure 1 As shown, the specific steps include:

[0067] S1. Preparation of substrates with microscopically complex surfaces:

[0068] (a) Pour polydimethylsiloxane (PDMS) and curing liquid into a Petri dish and mix them. After the bubbles dissipate, place it at 60°C to cure for 2 hours. Then, pour a small amount of 10 μm diameter SiO2 microsphere powder on it and spread it evenly with a hard object to evenly distribute the SiO2 microsphere powder on the surface.

[0069] (b) Cut the single crystal silicon wafer into 1cm 2 A square silicon wafer is spin-coated with Norland NOA 61 UV curing adhesive at a speed of 3000 rpm for 1 minute; the side of the single crystal silicon wafer spin-coated with the UV curing adhesive is placed on the side where the SiO2 microsphere powder is located in step (a), and the mixture is irradiated with a 365 nm wavelength, 35 W power UV lamp for at least 1 minute to cure the mixture, and then the square silicon wafer is torn off, i.e., the SiO2 microsphere powder is transferred to the square silicon wafer to serve as a substrate with a microscopically complex surface;

[0070] S2. Spin-coat a layer of Norland NOA 61 UV-curing adhesive on the microscopically complex surface of the substrate at a spin-coating speed of 1000-10000 rpm for 100 s until the surface is evenly filled. Irradiate the UV-curing adhesive with a UV lamp at a wavelength of 365 nm and a power of 35 W for 30 s to cure the adhesive layer.

[0071] S3, placing the cured adhesive layer under an oxygen plasma cleaning machine with a power of 300 W and an oxygen flow rate of 1 mL / min to obtain a hydrophilic surface on the cured adhesive layer of the substrate;

[0072] S4. Assemble a polystyrene microsphere film on a hydrophilic surface using the air-liquid interface self-assembly method. The detailed steps are as follows:

[0073] Step 1), take <100> A 4-inch single-crystal silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water, drying it, and then cleaning it with oxygen plasma.

[0074] Step 2), preparing a polystyrene microsphere dispersion with a concentration of 2.5 wt% and a diameter of 500 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and ultrasonicating for 5 minutes to obtain a polystyrene microsphere solution;

[0075] 8 mL of deionized water was first added to the hydrophilic surface of a single-crystal silicon wafer. A polystyrene microsphere solution was then added along the edge of the single-crystal silicon wafer. Finally, 10 μL of a 1 mol / L SDS solution was added along the edge of the single-crystal silicon wafer. The SDS solution filled the gaps between the polystyrene microspheres, forming a monolayer polystyrene microsphere array on the single-crystal silicon wafer.

[0076] Step 3) adding 100 μL of 0.1 mol / L sodium dodecyl sulfate solution (SDS solution) to 1 L of water, immersing the single crystal silicon wafer with the monolayer polystyrene microsphere array in the water, and the monolayer polystyrene microsphere array floats on the water surface;

[0077] Step 4), immersing the substrate in step S3 in water with the hydrophilic surface of the cured adhesive layer facing upward, and scooping up the single-layer polystyrene microsphere array from below the liquid surface, and transferring the single-layer polystyrene microsphere array to the hydrophilic surface, thereby preparing a polystyrene microsphere film on the cured adhesive layer of the substrate;

[0078] S5, the substrate of the prepared polystyrene microsphere film was placed in a Quorum Q150RS Plus magnetron sputtering instrument, and a gold film was sputtered on the polystyrene microsphere film at a current of 20 mA for 200 s to a thickness of 50 nm. Figure 4 composite product of

[0079] S6. Place the square silicon wafer with the gold film sputtered into a calcining furnace and calcine it at 1050°C for 2 hours to obtain a hexagonal non-close-packed gold particle array based on a microscopically complex surface. Figure 5 shown.

[0080] Example 3

[0081] This embodiment provides a method for preparing a hexagonal non-close-packed gold particle array based on a microscopic complex surface. The preparation process is as follows: Figure 1 As shown, the specific steps include:

[0082] S1. Preparation of substrates with microscopically complex surfaces:

[0083] (a) P-type <100> Crystal orientation single crystal silicon wafer cut into 2cm 2 The square silicon wafer was washed with ethanol and water and dried;

[0084] (b) Add 1 mL of 40% hydrofluoric acid to 19 mL of deionized water, soak the cleaned square silicon wafer in the solution for 1 minute, then rinse with deionized water and dry.

[0085] (c) Weigh 4.5 g potassium phosphate (K3PO4) and 0.9 g potassium metasilicate (K2SiO3) and add them to 24.6 mL deionized water. Heat the water to 90°C and soak the square silicon wafer in the water for 36 minutes.

[0086] (d) The soaked square silicon wafer is placed in ethanol and water for ultrasonic cleaning for 5 minutes. Figure 6 A square silicon wafer with an array of microscopic pyramids serves as a substrate with a microscopically complex surface;

[0087] S2. Spin-coat a layer of Norland NOA 61 UV-curing adhesive on the microscopically complex surface of the substrate at a spin-coating speed of 10,000 rpm for 20 seconds until the surface is evenly filled. Irradiate the UV-curing adhesive with a UV lamp at a wavelength of 365 nm and a power of 35 W for 30 seconds to cure the adhesive layer.

[0088] S3, placing the cured adhesive layer under an oxygen plasma cleaning machine with a power of 100 W and an oxygen flow rate of 100 mL / min to obtain a hydrophilic surface on the cured adhesive layer of the substrate;

[0089] S4. Assemble a polystyrene microsphere film on a hydrophilic surface using the air-liquid interface self-assembly method. The detailed steps are as follows:

[0090] Step 1), take <100> A 4-inch single-crystal silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water, drying it, and then cleaning it with oxygen plasma.

[0091] Step 2), preparing a polystyrene microsphere dispersion with a concentration of 5 wt% and a diameter of 500 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and ultrasonicating for 5 minutes to obtain a polystyrene microsphere solution;

[0092] 8 mL of deionized water was first added to the hydrophilic surface of a single-crystal silicon wafer. A polystyrene microsphere solution was then added along the edge of the single-crystal silicon wafer. Finally, 10 μL of a 2 mol / L SDS solution was added along the edge of the single-crystal silicon wafer. The SDS solution filled the gaps between the polystyrene microspheres, forming a monolayer polystyrene microsphere array on the single-crystal silicon wafer.

[0093] Step 3) Add 100 μL of 0.1 mol / L sodium dodecyl sulfate solution (SDS solution) to 1 L of water, immerse the square silicon wafer with the microscopic pyramid array in the water, and float the single-layer polystyrene microsphere array on the water surface;

[0094] Step 4), immersing the substrate in step S3 in water with the hydrophilic surface of the cured adhesive layer facing upward, and scooping up the single-layer polystyrene microsphere array from below the liquid surface, and transferring the single-layer polystyrene microsphere array to the hydrophilic surface, thereby preparing a polystyrene microsphere film on the cured adhesive layer of the substrate;

[0095] S5. Place the substrate with the prepared polystyrene microsphere film in a Quorum Q150RS Plus magnetron sputtering instrument, and sputter a gold film on the polystyrene microsphere film at a current of 20 mA for 200 s to a thickness of 50 nm.

[0096] S6. Place the square silicon wafer with the gold film sputtered into a calcining furnace and calcine it at 1050°C for 2 hours to obtain a hexagonal non-close-packed gold particle array based on a microscopically complex surface. Figure 7 shown.

[0097] Example 4

[0098] This embodiment provides a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, and a secondary calcination method based on a SiO2 microsphere array with a diameter of 5 μm, which specifically includes the following steps:

[0099] S1. Preparation of substrates with microscopically complex surfaces:

[0100] (a) Pour polydimethylsiloxane (PDMS) and curing liquid into a Petri dish and mix them. After the bubbles dissipate, place it at 60°C to cure for 2 hours. Then, pour a small amount of 5μm diameter SiO2 microsphere powder on it and spread it evenly with a hard object to evenly distribute the SiO2 microsphere powder on the surface.

[0101] (b) Cut the single crystal silicon wafer into 1cm 2 A square silicon wafer is spin-coated with Norland NOA 61 UV curing adhesive at a speed of 10,000 rpm for 1 minute. The side of the single crystal silicon wafer on which the UV curing adhesive is spin-coated is placed in contact with the side of the SiO2 microsphere powder in step (a), and the mixture is irradiated with a UV lamp at a wavelength of 365 nm and a power of 35 W for at least 1 minute to cure the mixture. The square silicon wafer is then removed, and the SiO2 microsphere powder is transferred to the square silicon wafer. The wafer is then placed in a calcining furnace and calcined at a temperature of at least 500° C. for at least 1 hour to obtain a SiO2 microsphere array with a diameter of 5 μm on the single crystal silicon wafer. Figure 8 As shown, as a substrate with a microscopically complex surface;

[0102] S2. Spin-coat a layer of Norland NOA 61 UV-curing adhesive on the microscopically complex surface of the substrate at a spin-coating speed of 10,000 rpm for 50 seconds until the surface is evenly filled. Irradiate the UV-curing adhesive with a UV lamp at a wavelength of 365 nm and a power of 35 W for 30 seconds to cure the adhesive layer.

[0103] S3, placing the cured adhesive layer under an oxygen plasma cleaning machine with a power of 15W and an oxygen flow rate of 10mL / min to obtain a hydrophilic surface on the cured adhesive layer of the substrate; Figure 9 As shown;

[0104] S4. Assemble a polystyrene microsphere film on a hydrophilic surface using the air-liquid interface self-assembly method. The detailed steps are as follows:

[0105] Step 1), take <100> A 4-inch single-crystal silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water, drying it, and then cleaning it with oxygen plasma.

[0106] Step 2), preparing a polystyrene microsphere dispersion with a concentration of 2.5 wt% and a diameter of 500 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and ultrasonicating for 5 minutes to obtain a polystyrene microsphere solution;

[0107] First, 5 mL of deionized water was added to the hydrophilic surface of the single-crystal silicon wafer. Then, a polystyrene microsphere solution was added along the edge of the single-crystal silicon wafer. Finally, 50 μL of a 0.1 mol / L SDS solution was added along the edge of the single-crystal silicon wafer. The SDS solution filled the gaps between the polystyrene microspheres, forming a single-layer polystyrene microsphere array on the single-crystal silicon wafer.

[0108] Step 3) adding 300 μL of 0.1 mol / L sodium dodecyl sulfate solution (SDS solution) to 1 L of water, immersing the single crystal silicon wafer with the monolayer polystyrene microsphere array in the water, and the monolayer polystyrene microsphere array floats on the water surface;

[0109] Step 4), immersing the substrate in step S3 in water with the hydrophilic surface of the cured adhesive layer facing upward, and scooping up the single-layer polystyrene microsphere array from below the liquid surface, and transferring the single-layer polystyrene microsphere array to the hydrophilic surface, thereby preparing a polystyrene microsphere film on the cured adhesive layer of the substrate;

[0110] S5, the substrate of the prepared polystyrene microsphere film was placed in a Quorum Q150RS Plus magnetron sputtering instrument, and a gold film was sputtered on the polystyrene microsphere film at a current of 20 mA for 200 s to a thickness of 50 nm. Figure 10 (Sectional view) and Figure 11 (Top view) of the composite product shown;

[0111] S6. Place the square silicon wafer with the gold film sputtered into a calcining furnace and calcine at 1050°C for 3 hours to obtain a hexagonal non-close-packed gold nanoparticle array based on a SiO2 microsphere array with a diameter of 5 μm. Figure 12 shown.

[0112] Example 5

[0113] This embodiment provides a method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, and a secondary calcination method based on a SiO2 microsphere array with a diameter of 10 μm, which specifically includes the following steps:

[0114] S1. Preparation of substrates with microscopically complex surfaces:

[0115] (a) Pour polydimethylsiloxane (PDMS) and curing liquid into a Petri dish and mix them. After the bubbles dissipate, place it at 60°C to cure for 2 hours. Then, pour a small amount of 10 μm diameter SiO2 microsphere powder on it and spread it evenly with a hard object to evenly distribute the SiO2 microsphere powder on the surface.

[0116] (b) Cut the single crystal silicon wafer into 1cm 2 A square silicon wafer is spin-coated with Norland NOA 61 UV curing adhesive at a speed of 3000 rpm for 1 minute. The side of the single crystal silicon wafer spin-coated with the UV curing adhesive is placed on the side where the SiO2 microsphere powder is located in step (a), and the mixture is irradiated with a UV lamp with a wavelength of 365 nm and a power of 35 W for at least 1 minute to cure the mixture. The square silicon wafer is then torn off, and the SiO2 microsphere powder is transferred to the square silicon wafer. The wafer is placed in a calcining furnace and calcined at a temperature of at least 500° C. for at least 1 hour to obtain a SiO2 microsphere array with a diameter of 10 μm on the single crystal silicon wafer. Figure 13 As shown, as a substrate with a microscopically complex surface;

[0117] S2. Spin-coat a layer of Norland NOA 61 UV-curing adhesive on the microscopically complex surface of the substrate at a spin-coating speed of 1000-10000 rpm for 200 s until the surface is evenly filled. Irradiate the UV-curing adhesive with a UV lamp at a wavelength of 365 nm and a power of 35 W for 30 s to cure the adhesive layer.

[0118] S3, placing the cured adhesive layer under an oxygen plasma cleaning machine with a power of 200W and an oxygen flow rate of 10mL / min to obtain a hydrophilic surface on the cured adhesive layer of the substrate; Figure 14 As shown;

[0119] S4. Assemble a polystyrene microsphere film on a hydrophilic surface using the air-liquid interface self-assembly method. The detailed steps are as follows:

[0120] Step 1), take <100> A 4-inch single-crystal silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water, drying it, and then cleaning it with oxygen plasma.

[0121] Step 2), preparing a polystyrene microsphere dispersion with a concentration of 10 wt% and a diameter of 500 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and ultrasonicating for 5 minutes to obtain a polystyrene microsphere solution;

[0122] First, 5 mL of deionized water was added to the hydrophilic surface of a single-crystal silicon wafer. Then, a polystyrene microsphere solution was added along the edge of the single-crystal silicon wafer to allow the polystyrene microspheres to self-assemble. Then, 30 μL of a 2 mol / L SDS solution was added along the edge of the single-crystal silicon wafer to fill the gaps between the polystyrene microspheres, forming a single-layer polystyrene microsphere array on the single-crystal silicon wafer.

[0123] Step 3) adding 200 μL of 0.5 mol / L sodium dodecyl sulfate solution (SDS solution) to 1 L of water, immersing the single crystal silicon wafer with the monolayer polystyrene microsphere array in the water, and the monolayer polystyrene microsphere array floats on the water surface;

[0124] Step 4), immersing the substrate in step S3 in water with the hydrophilic surface of the cured adhesive layer facing upward, and scooping up the single-layer polystyrene microsphere array from below the liquid surface, and transferring the single-layer polystyrene microsphere array to the hydrophilic surface, thereby preparing a polystyrene microsphere film on the cured adhesive layer of the substrate;

[0125] S5. Place the prepared polystyrene microsphere film substrate into a Quorum Q150RS Plus magnetron sputtering instrument, and sputter a gold film on the polystyrene microsphere film at a current of 20 mA for 200 s to a thickness of 50 nm. Figure 15 (Sectional view) and Figure 16 (Top view) of the composite product shown;

[0126] S6. Place the square silicon wafer with the gold film sputtered into a calcining furnace and calcine at 1050°C for 2 hours to obtain a hexagonal non-close-packed gold nanoparticle array based on a SiO2 microsphere array with a diameter of 10 μm. Figure 17 shown.

[0127] Those skilled in the art will appreciate that the foregoing descriptions are merely specific embodiments of the present invention, and not exhaustive. It should be noted that numerous variations and modifications are possible for those skilled in the art, and all such variations and modifications that do not exceed the scope of the claims should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface, characterized in that: The steps include: S1. Spin-coating a curing adhesive onto a substrate with a microscopically complex surface to make the substrate filled and flat, and curing the spin-coated curing adhesive to obtain a cured adhesive layer; S2, placing the substrate with the cured adhesive layer under an oxygen plasma cleaning machine to prepare a hydrophilic surface on the cured adhesive layer of the substrate; S3, assembling a monolayer of hexagonally close-packed polystyrene microspheres on the hydrophilic surface of the cured adhesive layer using a gas-liquid interface self-assembly method, wherein the diameter of the polystyrene microspheres is 200-2000 nm, to form a polystyrene microsphere film; S4. A gold film with a thickness of 10-200 nm is sputtered on the polystyrene microsphere film using a magnetron sputtering apparatus, and then calcined at 500-1300°C for 0.5-8 hours to obtain a hexagonal non-close-packed gold particle array based on a microscopically complex surface.

2. The method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface according to claim 1, characterized in that: The curing adhesive in step S1 is a Norland NOA 61 UV curing adhesive.

3. The method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface according to claim 2, characterized in that: The ultraviolet curing adhesive is spin-coated on the substrate at a rotation speed of 500-10000 rpm for 10-300s, and then placed under an ultraviolet lamp for irradiation curing.

4. The method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface according to claim 3, characterized in that: The ultraviolet lamp is an LED ultraviolet UV curing lamp produced by Tiandou Lighting Appliance Factory in Henglan Town, Zhongshan City, model AC85-260V, with a wavelength of 365nm and a power of 35w.

5. The method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface according to claim 1, characterized in that: The oxygen plasma cleaning machine in step S2 is a model TS-SYPL05 product of Shenzhen Eastcom High-Tech Automation Equipment Co., Ltd., with a power of 15-300W, an oxygen flow rate of 1-600mL / min, and a cleaning time of 20-1000s.

6. The method for preparing a hexagonal non-close-packed gold particle array based on a microscopically complex surface according to claim 1, characterized in that: The details of the gas-liquid interface self-assembly method in step S3 are as follows: 1) Take <100> The monocrystalline silicon wafer with a hydrophilic surface is prepared by washing it with ethanol and water in sequence, drying it, and then cleaning it with oxygen plasma. 2) preparing a polystyrene microsphere dispersion having a concentration of 0.5-10 wt % and a diameter of 200-2000 nm, mixing the polystyrene microsphere dispersion with ethanol and acetone in a volume ratio of 2:1:1, and sonicating for 1-30 minutes to obtain a polystyrene microsphere solution; 3) adding 2-12 mL of deionized water to the hydrophilic surface of the single crystal silicon wafer, adding a polystyrene microsphere solution along the edge of the single crystal silicon wafer, and then adding 5-50 μL of a 0.1-5 mol / L sodium dodecyl sulfate solution (SDS solution) along the edge of the single crystal silicon wafer to self-assemble into a monolayer polystyrene microsphere array on the single crystal silicon wafer; 4) adding 30 μL to 500 μL of a 0.1-5 mol / L SDS solution dropwise to 1 L of water, immersing the single-crystalline silicon wafer having the monolayer polystyrene microsphere array in the water, with the monolayer polystyrene microsphere array floating on the water surface; immersing the substrate with the hydrophilic surface facing upward in water, transferring the monolayer polystyrene microsphere array to the hydrophilic surface, and removing the substrate, thereby producing a polystyrene microsphere film on the substrate.

7. A hexagonal non-close-packed gold particle array based on a microscopically complex surface prepared by the preparation method according to any one of claims 1 to 6.

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