Preparation method and application of silicon nanopore array

Abstract

The invention discloses a preparation method and application of a silicon nanopore array, and relates to the field of nanopore array manufacturing. The method comprises the following steps: taking an AAO film as a nano template, and transferring the AAO film to the surface of a silicon substrate; depositing a silver nanoparticle array on the AAO thin film to form large-area ordered silver nanoparticle arrangement; and removing the AAO thin film to obtain a silver nanoparticle array on the silicon substrate, immersing the silicon substrate containing silver nanoparticles into an etching solution for reaction, and forming the silicon nanopore array by taking the silver nanoparticles as a metal catalyst. Compared with the prior art, the method has the advantages that the geometrical shape of the nanopore can be accurately controlled, and the method has the characteristics of low cost, high adaptability and repeatability and is suitable for large-scale production to meet diversified requirements in different fields.

Description

Technical Field

[0001] This invention relates to the field of nanopore array manufacturing technology, and more specifically, to a method for preparing a silicon nanopore array and its application. Background Technology

[0002] Silicon nanopore arrays are widely used in various fields, such as biomedicine, environmental monitoring, chemical synthesis, and energy storage and conversion, due to their high stability, long lifespan, and excellent compatibility with semiconductor and microfluidic technologies. These fields have specific requirements for pore size and morphology, thus necessitating precise, scalable, and cost-effective fabrication methods to meet the diverse needs of different fields.

[0003] Recent advances in nanopore fabrication have spurred the development of various techniques, including wet etching, ion track etching, and electron beam lithography-assisted reactive ion etching (electron beam RIE). However, wet etching is limited by size uniformity issues and the generation of relatively large pores, thus restricting its applications; ion track etching is limited to polymer films and results in uneven pore distribution due to the unpredictability of ion trajectories; electron beam RIE requires expensive equipment and is time-consuming, limiting its scalability for large-scale production.

[0004] In addition to the conventional techniques mentioned above, some solutions attempt to prepare nanopores through multilayer film structures on SOI substrates and metal particle dispersion etching, but these solutions have inherent drawbacks, such as reliance on SiN thin films and adhesives to construct physical isolation, high process complexity, high equipment costs, and poor uniformity of nanopore distribution.

[0005] These challenges highlight the need for novel fabrication methods that combine high precision with cost-effective scalability, better geometry control, and simpler operating procedures. Summary of the Invention

[0006] To overcome the shortcomings of the prior art that cannot simultaneously achieve high precision and low cost, the present invention provides a method for fabricating silicon nanopore arrays and their applications.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0008] Firstly, a method for fabricating a silicon nanopore array includes:

[0009] An AAO film is used as a nanotemplate and transferred to the surface of a silicon substrate; wherein the AAO film has a highly ordered nanoporous structure.

[0010] A silver nanoparticle array is deposited on the AAO film to form a large-area ordered arrangement of silver nanoparticles.

[0011] The AAO film is removed to obtain a silver nanoparticle array on a silicon substrate. The silicon substrate containing silver nanoparticles is then immersed in an etching solution to react, using the silver nanoparticles as a metal catalyst to form a silicon nanopore array.

[0012] In a second aspect, a silicon nanopore array is prepared using the preparation method described in the first aspect.

[0013] Thirdly, a detection device employing the silicon nanopore array described in the second aspect.

[0014] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0015] This application utilizes an AAO template combined with silver nanoparticle-assisted chemical etching to promote the orderly and repeatable arrangement of silver nanoparticles on a silicon surface, achieving precise control over the geometry of nanopores. This not only overcomes the limitations of traditional methods in balancing high precision and low cost, but also addresses the inability of existing equipment to achieve uniform pore size. Compared to existing technologies, this application features low cost, strong adaptability, and repeatability, making it suitable for large-scale production to meet diverse needs across various fields. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of the method for preparing the silicon nanopore array in Embodiment 1 of this application.

[0017] Figure 2 This is another schematic diagram of the process for preparing the silicon nanopore array in Embodiment 1 of this application.

[0018] Figure 3 These are photographs of the AAO thin film, the silicon wafer after transferring the AAO thin film, and the silicon wafer after silver plating, as shown in Example 1 of this application.

[0019] Figure 4 These are photographs of the silicon wafer before and after metal-assisted chemical etching in Example 1 of this application.

[0020] Figure 5 This is a SEM image of the cross-section of a silicon nanopore array obtained by etching silver nanoparticles of different diameters in Example 2 of this application.

[0021] Figure 6 These are SEM images of the cross-sectional morphology of the nanopore array at different etching times in Example 2 of this application.

[0022] Figure 7 These are SEM images of the cross-sectional morphology of the nanopores at different etching temperatures in Example 2 of this application.

[0023] Figure 8These are SEM images of the cross-sectional morphology of nanopores under different H2O2 concentrations in Example 2 of this application.

[0024] Figure 9 These are SEM images of the cross-sectional morphology of nanopores under different ambient light conditions in Example 2 of this application. Detailed Implementation

[0025] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the description of embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of units is not necessarily limited to those units, but may include other units not explicitly listed or inherent to those processes, methods, products, or apparatuses. The term "determine" broadly covers a wide variety of actions, including acquiring, calculating, processing, deriving, investigating, searching (e.g., searching in a table, database, or other data structure), probing, and similar actions; it may also include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), and similar actions; it may also include generating, creating, establishing, and similar actions; and parsing, selecting, choosing, and similar actions, etc. Definitions of other terms will be given in the following description.

[0026] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. Furthermore, in the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if there is transmission of electrical signals or data between the connected objects.

[0027] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent.

[0028] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions;

[0029] It will be understood by those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings.

[0030] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] Example 1

[0032] This embodiment provides a method for fabricating a silicon nanopore array, see reference. Figure 1 , Figure 2 ,include:

[0033] S1. Using an AAO (anodic aluminum oxide) film as a nanotemplate, the AAO film is transferred to the surface of a silicon substrate (also known as a silicon wafer or silicon wafer substrate); wherein the AAO film has a highly ordered nanoporous structure;

[0034] S2. Deposit an array of silver nanoparticles on the AAO film to form a large-area ordered arrangement of silver nanoparticles.

[0035] S3. Remove the AAO film to obtain a silver nanoparticle array on a silicon substrate, and immerse the silicon substrate containing silver nanoparticles in an etching solution to react, using silver nanoparticles as a metal catalyst to form a silicon nanopore array.

[0036] It should be noted that metal-assisted chemical etching (MACE) was first proposed in 1997. It utilizes metal particles to improve etching efficiency and is a simple, low-cost, and efficient method for large-scale fabrication of silicon nanopore arrays.

[0037] Compared with traditional methods, this embodiment is based on metal-assisted chemical etching. Using silver-assisted chemical etching not only overcomes the defects of traditional methods, but also overcomes the problem that existing technology and equipment cannot achieve uniformity of pore size. It can prepare nanopores with cylindrical, conical and spiral structures, achieving a nanopore density of up to 109 per square centimeter, with a very high aspect ratio and significant advantages in structural consistency. It is not only simple to operate and low in cost, but also improves the preparation efficiency. It provides a new technical means for preparing precise, scalable and cost-effective nanopore arrays, which can directly support high-sensitivity biosensing applications.

[0038] It should also be noted that the above embodiments utilize the spatial confinement of highly ordered nanopores in the AAO film to generate an array of single-particle distribution of silver nanoparticles on the silicon substrate surface, which is different from the technical path that relies on physical isolation of multilayer SiN films and multi-step etching to adapt to heterogeneous structures.

[0039] Furthermore, current industry attempts to fabricate nanopores using SiN-based multilayer film etching often encounter problems such as film residue and pore collapse. Compared to these methods, this embodiment offers the following core advantages:

[0040] (1) The complexity of the process is greatly reduced: the process eliminates the need for multi-step film processing such as 'SiN thin film deposition / patterning, protective layer coating / removal', and does not rely on SiN thin film or adhesive to build physical isolation. Only 3 core processes are required: "AAO template transfer - silver deposition - single-step etching". The process flow is significantly reduced and the equipment cost is significantly reduced (no need for multi-layer film deposition or photoresist development equipment).

[0041] (2) Breakthrough in structural consistency: Relying on AAO template confinement, the nanopore diameter deviation is <5% and the aspect ratio deviation is <3%, which is more than 4 times higher than the SiN-based multilayer film etching method for preparing nanopores (diameter deviation >20%), making it suitable for high-precision scenarios such as single-particle detection of biomolecules.

[0042] (3) Improved etching efficiency: Single-step catalytic etching takes 60% less time than multi-step etching, and the roughness of the hole sidewall is reduced by 40% due to the absence of film layer interface interference (SEM characterization verification), which helps to facilitate large-scale production.

[0043] In some preferred embodiments, the silicon substrate is an N-type heavily doped single-crystal silicon wafer with a resistivity of 0.1 Ω·cm.

[0044] It is understood that the AAO film used in this embodiment is typically only a few hundred nanometers thick and is very fragile. In some preferred embodiments, the AAO film is supported by a PMMA (polymethyl methacrylate) film before being transferred to the silicon substrate surface, resulting in an AAO film supported by PMMA, such as... Figure 3 As shown in (a).

[0045] In some alternative embodiments, transferring the AAO thin film onto the silicon substrate surface includes:

[0046] Clean the silicon substrate;

[0047] The AAO membrane was soaked in acetone solution to remove PMMA and then rinsed in deionized water.

[0048] The AAO film, after PMMA removal, is retrieved from the deionized water using the silicon substrate, and then adsorbed onto the surface of the silicon substrate. The silicon substrate after transferring the AAO film is as follows: Figure 3 As shown in (b).

[0049] In some specific implementations, the silicon substrate with the AAO film attached is placed in a self-priming box and stored in a vacuum bag.

[0050] Furthermore, the cleaning process of the silicon substrate includes:

[0051] The silicon substrate is soaked in acetone to remove the adhesive.

[0052] The silicon substrate was cleaned in a water bath using a piranha solution, and finally rinsed with deionized water.

[0053] In some specific implementation processes, the silicon substrate is cleaned with piranha solution in a water bath at 90℃-110℃ for 20-30 minutes, and then rinsed with deionized water.

[0054] In some preferred embodiments, a silver nanoparticle array is deposited on the surface of the AAO thin film using a magnetron sputtering method, with a deposition thickness of 30 nm-50 nm. The silicon substrate after silver deposition is shown below. Figure 3 As shown in (c).

[0055] It should be understood that the diameter of the silver nanoparticles deposited on the silicon substrate is positively correlated with the pore size of the AAO film, that is, the diameter of the silver nanoparticles increases with the increase of the pore size of the AAO film. Therefore, the method for fabricating silicon nanopore arrays on a silicon substrate limited by the diameter of the silver nanoparticles is also within the scope of protection of this application.

[0056] In some preferred embodiments, the controllable preparation parameters in the fabrication process of the silicon nanopore array include the AAO film pore size, ambient light during etching, etching duration, etching temperature, and / or the etchant ρ value representing the ratio of HF to H2O2 in the etching solution.

[0057] More specifically,

[0058] In the formula, [HF] represents the molar concentration of hydrofluoric acid in the etching solution; [H2O2] represents the molar concentration of hydrogen peroxide in the etching solution.

[0059] It should be emphasized that by adjusting the controllable preparation parameters, those skilled in the art can achieve controllable fabrication of the nanopore morphology on the prepared silicon nanopore array, thereby achieving high precision and strong adaptability to meet the diverse needs of different fields.

[0060] In some alternative embodiments, the preparation process of the etching solution includes:

[0061] Deionized water was added to a Teflon beaker using a pipette; wherein the Teflon beaker was equipped with a magnetic stir bar.

[0062] After changing the pipette tip, use the pipette to add HF solution and H2O2 solution into the Teflon beaker; wherein the concentration of HF solution is 3mol / L-5mol / L and the concentration of H2O2 solution is 0.14mol / L-0.84mol / L.

[0063] After sealing the Teflon beaker with sealing adhesive, the liquid in the Teflon beaker is stirred with a magnetic stirrer to ensure thorough mixing, thus completing the preparation of the etching solution.

[0064] In some specific implementations, the etching solution is prepared as follows:

[0065] Place the magnetic stir bar into the Teflon beaker containing the etching solution. Pipette 12.5-14.5 ml of deionized water into the beaker. Next, change the pipette tip and add 2.5-4.5 ml of HF solution and 0.4-0.6 ml of H₂O₂ solution to the beaker (HF concentration 3-5 mol / L, H₂O₂ concentration 0.14-0.84 mol / L). Seal the beaker with adhesive tape. Place the beaker on the magnetic stir bar and adjust the speed knob to 400-800 rpm. Stir for one minute to ensure the three liquids are thoroughly mixed, completing the etching solution preparation.

[0066] In some optional embodiments, during the fabrication of the silicon nanopore array, the AAO film with a pore size of 50nm-100nm is used as a nanotemplate, and / or an etching reaction is carried out in an etchant with a p value of 80%-95% in a dark, room temperature environment.

[0067] In some preferred embodiments, the etching process of the silicon substrate includes:

[0068] Use Teflon tweezers to hold the edge of the silicon substrate to prevent silver nanoparticles from falling off. With the side of the silicon substrate containing silver nanoparticles facing up, tilt the silicon substrate into the etching solution. After the silicon substrate sinks to the bottom of the etching solution, release the Teflon tweezers.

[0069] After a preset etching time, the edges of the silicon substrate are held with Teflon tweezers to prevent damage to the nanopore array structure, and the silicon substrate is removed from the etching solution and placed in deionized water for cleaning.

[0070] The cleaned silicon substrate was immersed in anhydrous ethanol and then dried in a vacuum drying oven to obtain the silicon nanopore array.

[0071] It should be noted that the purpose of anhydrous ethanol is to avoid structural damage caused by the surface tension of water during the drying process.

[0072] In some specific implementation processes, the preset etching time is 4-6 minutes.

[0073] In some specific implementations, the etching process for the silicon substrate without removing the AAO film includes:

[0074] S31. Take two clean Teflon beakers and fill them with an appropriate amount of deionized water. Take one clean beaker and fill it with an appropriate amount of anhydrous ethanol. Seal the beaker with sealing adhesive for later use.

[0075] S32. Place the polyimide tape on the area with the AAO film and press it gently with your fingers to ensure that the tape is tightly bonded to the AAO film. Then quickly peel it off to remove the AAO film.

[0076] S33. Carefully hold the edge of the silicon wafer with Teflon tweezers and insert it into the etching solution at an angle, with the side containing the silver nanoparticles facing up. Start timing at the same time. Because the silicon wafer is thin, to prevent it from floating on the surface of the etching solution, wait until the silicon wafer sinks to the bottom of the beaker before releasing the tweezers.

[0077] During the etching process, observe the surface of the silicon wafer in the beaker. If there are a large number of air bubbles, shake the beaker every 1-2 minutes to help the bubbles detach from the silicon wafer surface. Before the timing ends, place tweezers in the beaker and wait. Once the timing is complete, immediately remove the silicon wafer.

[0078] S34. Place the removed silicon wafers sequentially into two pre-prepared Teflon beakers, clean each for 1-3 minutes, then immerse them in anhydrous ethanol for 1-2 minutes. Finally, dry them in a vacuum drying oven for 3-7 minutes to obtain the prepared nanopore array, as shown below. Figure 4 As shown in (b), compared with the polished surface when removing the AAO film ( Figure 4 Compared to (a), the surface of the silicon nanopore array silicon wafer appears black.

[0079] This embodiment also provides a silicon nanopore array, which is prepared using the aforementioned method.

[0080] This embodiment also provides a detection device that utilizes the aforementioned silicon nanopore array.

[0081] As a non-limiting example, the detection device is an environmental pollutant detection device or a biomolecule detection device.

[0082] Example 2

[0083] To verify the effect of the controllable preparation parameters in Example 1 on the final silicon nanopore array, some comparative experiments are provided in this example.

[0084] To investigate the influence of AAO thin films with different pore sizes and spacings on the controllable fabrication of nanopores, the specific experimental steps included: using silicon wafers with transferred AAO thin films of 40nm-100nm pore sizes, etching silver nanoparticles of different diameters for 5 minutes at room temperature and under indoor light conditions in an etching solution with ρ = 94.1% (H2O, HF, H2O2 volume ratio of 27:7:1). The results showed that the diameter of the nanopores increased with increasing silver particle diameter. SEM (Scanning Electron Microscope) images of silver nanoparticles of different diameters and the cross-sections of the etched nanopores are shown below. Figure 5 As shown in (a)-(d).

[0085] The different types of AAO films and their specific parameters are shown in Table 1.

[0086] Table 1. AAO Thin Film Parameters

[0087]

[0088]

[0089] To investigate the effect of etching time on the controllable fabrication of nanopore depth, the specific experimental steps included: First, a silicon wafer with a transferred AAO thin film of 60 nm aperture was selected. The etching solution had a concentration of 94.1%. Etching was performed at room temperature and under indoor lighting conditions for 1 min, 5 min, 10 min, and 15 min, respectively. The results showed that the nanopore depth was linearly positively correlated with the etching time. The cross-section of the silicon nanopore array was as follows: Figure 6 As shown in (a)-(d).

[0090] To investigate the effect of etching temperature on the controllable fabrication of nanopore depth, the specific experimental steps included: using a silicon wafer with a transferred AAO thin film of 60 nm diameter, an etching solution with a concentration of ρ = 94.1%, etching for 5 minutes under indoor light conditions, and setting the reaction temperatures to 0℃, 25℃, 40℃, and 80℃ respectively. The results showed a positive correlation between etching temperature and nanopore depth. The cross-sectional SEM image of the silicon nanopore array is shown below. Figure 7 As shown in (a)-(d).

[0091] To investigate the effect of the etchant density (ρ) on the controllable fabrication of nanopore depth, the specific experimental steps included: using a silicon wafer with a transferred AAO thin film of 60 nm diameter, and preparing etchants with ρ = 96.98%, 94.1%, 88.9%, and 84.3% respectively. The H2O2 concentrations of these four etchants were 0.14 M, 0.28 M, 0.56 M, and 0.84 M, respectively. Etching was performed at room temperature and under indoor light conditions for 10 minutes. The results showed that the only factor directly affecting the morphology and etching rate of the nanopores was the H2O2 concentration. Cross-sectional images of the nanopore array etched under different H2O2 concentrations are shown below. Figure 8 As shown in (a)-(d).

[0092] To investigate the effect of ambient light on the controllable fabrication of nanopore shapes during etching, the specific experimental steps included: using a silicon wafer with a transferred AAO thin film of 60 nm diameter, etching was performed for 5 minutes under the following conditions: etching solution ρ = 94.1% and room temperature, in darkness, indoor light (440 Lux), and xenon lamp (8500 Lux). The average depths of the silicon nanopores measured after the experiments were 3.53 m, 3.56 m, and 4 m, respectively, indicating that the nanopores under xenon lamp irradiation were approximately 13% deeper than those under darkness. Figure 9 As shown in (ac).

[0093] Furthermore, in this embodiment, the silicon nanoarray morphology was best prepared under the conditions of AAO film pore size of 60 nm, dark conditions, room temperature, and etchant p value of 94.1%.

[0094] It is understood that the options in Embodiment 1 above also apply to this embodiment, so they will not be described again here.

[0095] The same or similar labels correspond to the same or similar parts;

[0096] The terms used to describe positional relationships in the accompanying drawings are for illustrative purposes only and should not be construed as limiting this application.

[0097] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0098] In different specific implementations, the methods or systems described in this application can be implemented in software, hardware, or a combination thereof. Furthermore, the order of the method steps can be changed, and various elements can be added, reordered, combined, omitted, or modified.

[0099] Obviously, the above embodiments of this application are merely examples for clearly illustrating this application, and are not intended to limit the implementation of this application, nor are they intended to limit this application. For those skilled in the art, other variations or modifications can be made based on the above description. The separate structural / functional modules or units can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part. The structure and function of the separate components can be implemented as a combined structure or component. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A method for fabricating a silicon nanopore array, characterized in that, include: An AAO film is used as a nanotemplate and transferred onto the surface of a silicon substrate; wherein the AAO film has a highly ordered nanoporous structure. A silver nanoparticle array is deposited on the AAO film to form a large-area ordered arrangement of silver nanoparticles. The AAO film is removed to obtain a silver nanoparticle array on a silicon substrate. The silicon substrate containing silver nanoparticles is then immersed in an etching solution to react, using the silver nanoparticles as a metal catalyst to form a silicon nanopore array.

2. The method for fabricating a silicon nanopore array according to claim 1, characterized in that, The AAO film is supported beneath a PMMA film before being transferred to the silicon substrate surface.

3. The method for fabricating a silicon nanopore array according to claim 2, characterized in that, The process of transferring the AAO thin film onto the surface of a silicon substrate includes: Clean the silicon substrate; The AAO membrane was soaked in acetone solution to remove PMMA and then rinsed in deionized water. The AAO film after PMMA removal is retrieved from the silicon substrate in the ionized water, and the AAO film is adsorbed onto the surface of the silicon substrate.

4. The method for fabricating a silicon nanopore array according to claim 3, characterized in that, The cleaning process for the silicon substrate includes: The silicon substrate is soaked in acetone to remove the adhesive. The silicon substrate was cleaned in a water bath using a piranha solution, and finally rinsed with deionized water.

5. The method for fabricating a silicon nanopore array according to claim 1, characterized in that, Silver nanoparticle arrays were deposited on the surface of the AAO thin film using a magnetron sputtering method, with a deposition thickness of 30 nm-50 nm.

6. The method for fabricating a silicon nanopore array according to claim 1, characterized in that, The controllable preparation parameters in the fabrication process of the silicon nanopore array include the AAO film pore size, ambient light during etching, etching time, etching temperature, and / or the etchant ρ value representing the ratio of HF to H2O2 in the etching solution.

7. The method for fabricating a silicon nanopore array according to claim 6, characterized in that, The preparation process of the etching solution includes: Deionized water was added to a Teflon beaker using a pipette; wherein the Teflon beaker was equipped with a magnetic stir bar. After changing the pipette tip, use the pipette to add HF solution and H2O2 solution into the Teflon beaker; wherein the concentration of HF solution is 3mol / L-5mol / L and the concentration of H2O2 solution is 0.14mol / L-0.84mol / L. After sealing the Teflon beaker with sealing adhesive, the liquid in the Teflon beaker is stirred with a magnetic stirrer to ensure thorough mixing, thus completing the preparation of the etching solution.

8. The method for fabricating a silicon nanopore array according to claim 6, characterized in that, In the fabrication process of the silicon nanopore array, the AAO film with a pore size of 50nm-100nm is used as a nanotemplate, and / or an etching reaction is carried out in an etchant with a p value of 80%-95% in a dark, room temperature environment.

9. A method for fabricating a silicon nanopore array according to any one of claims 1-8, characterized in that, The etching process of the silicon substrate includes: Using Teflon tweezers to hold the edge of the silicon substrate with the side containing silver nanoparticles facing upwards, the silicon substrate is tilted and inserted into the etching solution. After the silicon substrate sinks to the bottom of the etching solution, the Teflon tweezers are released. After a preset etching time, the edge of the silicon substrate is held by the Teflon tweezers and removed from the etching solution, then placed in deionized water for cleaning. The cleaned silicon substrate was immersed in anhydrous ethanol and then dried in a vacuum drying oven to obtain the silicon nanopore array.

10. A silicon nanopore array, characterized in that, Prepared by the preparation method according to any one of claims 1-9.

Images