Silicon-based super lens and manufacturing method thereof

Abstract

The invention discloses a silicon-based super lens and a manufacturing method thereof. The manufacturing method comprises the following steps: providing a substrate; photoresist is arranged on the substrate; performing photoetching on the photoresist to form a nano column pattern; etching a plurality of grooves on the surface of the substrate by etching the nano-pillar pattern, so as to form a nano-pillar array structure with high aspect ratio on the substrate; and removing the photoresist to form the silicon-based super lens. The manufacturing method of the silicon-based lens is good in uniformity and simple in technological process, large-area manufacturing is easy, and the manufacturing efficiency of the silicon-based lens is improved by optimizing the side wall perpendicularity of the photoetching pattern, adjusting gas flow distribution, increasing the etching cycle number and prolonging the duration ratio of the inner side wall passivation phase in single cycle. The etching uniformity is obviously improved, the roughness of the side wall of the structural unit is reduced, and the phase regulation and control accuracy of the silicon nanorod is improved.

Description

Technical Field

[0001] This application relates to the field of optical components, and particularly to a silicon-based superlens and a manufacturing method thereof. Background Art

[0002] Traditional lenses rely on the curved surface shape to change the optical path difference to adjust the phase of light waves, so as to achieve functions such as focusing and imaging. However, traditional lenses have problems such as large volume, heavy weight, and complex manufacturing processes. Especially in the application fields of optical systems that require high precision and high integration, the limitations of traditional lenses in terms of system complexity and volume weight are more prominent. In recent years, as an emerging optical modulation means, the metasurface technology precisely modulates the phase, amplitude, and polarization of light waves through sub-wavelength scale nanostructure units, and is easy to prepare ultra-thin and lightweight optical elements. As an important application of the metasurface technology, the superlens has the advantages of thin thickness, light weight, and flexible design, and has gradually become a research hotspot in the optical field, providing a new idea for the development of miniaturized on-chip integrated optics. However, existing superlenses still have some problems, such as limited working bandwidth, low focusing efficiency, complex manufacturing process, and limited size of a single lens.

[0003] Therefore, there is an urgent need for a new manufacturing method of superlenses to solve the above problems, while simplifying the process flow and providing the possibility of wafer-level manufacturing, which can significantly reduce the production cost. The present invention breaks through the size limitation of traditional superlenses and provides a low-cost batch solution for the selective modulation technology of the electromagnetic spectrum, passive radiation receiving systems, and light field cameras for high-precision imaging. Summary of the Invention

[0004] The present invention aims to solve the problems of limited working bandwidth, low focusing efficiency, complex manufacturing process, and limited size of a single lens in the existing superlens preparation methods.

[0005] To achieve the above and other related purposes, an embodiment of the present application provides a manufacturing method of the silicon-based superlens, including: Providing a substrate; Setting a photoresist pattern layer on the substrate; By etching the photoresist pattern layer and the substrate, a plurality of grooves are etched in the area of the substrate surface not protected by the photoresist pattern layer, so as to form a nano-column array structure on the substrate; Removing the photoresist pattern layer to form a silicon-based superlens.

[0006] Optionally, the substrate is float zone single crystal silicon, the refractive index range of the float zone single crystal silicon is 3.4 - 3.6, and the resistivity range of the float zone single crystal silicon is 1000 - 20000 Ω·cm.

[0007] Optionally, the photoresist pattern layer is formed by deep ultraviolet lithography on the photoresist mask barrier layer.

[0008] Optionally, the photoresist mask barrier layer is formed by spin coating on the substrate.

[0009] Optionally, a bottom anti-reflection coating is provided before the photoresist mask barrier layer is provided.

[0010] Optionally, the exposure dose of the lithography process is 250 ± 30 mJ / cm2, and the focal plane offset is 0 ± 0.6 μm.

[0011] Optionally, the etching process is a dry etching process with a high aspect ratio.

[0012] Optionally, the dry etching process with a high aspect ratio is a pulsed etching with an alternating cycle of C4F8 / SF6 gas.

[0013] Optionally, the single gas cycle time in the dry etching process with a high aspect ratio is ≤ 3 seconds.

[0014] Optionally, the flow rate ratio of the sidewall passivation gas to the bottom etching gas in a single cycle of the dry etching process with a high aspect ratio is greater than 2 / 3.

[0015] Optionally, the ratio of the sidewall passivation process duration to the bottom etching process duration in a single cycle of the dry etching process with a high aspect ratio is ≥ 1.

[0016] Optionally, the number of cycles in the dry etching process with a high aspect ratio is ≥ 220 times.

[0017] Optionally, the geometric shape of the nanorods is one of silicon columns, elliptical columns, square columns, and triangular prisms.

[0018] Optionally, the height of the nanorods is 10 μm to 15 μm.

[0019] Optionally, the minimum diameter range of the nanorods is 0.5 μm to 0.6 μm, and the maximum diameter range is 2 μm to 4 μm.

[0020] Optionally, the center spacing of the nanorods is 2.6 μm to 5.2 μm.

[0021] Optionally, the maximum aspect ratio of the nanorods is greater than 30:1.

[0022] Optionally, the photoresist removal process is an oxygen plasma dry photoresist removal process.

[0023] Optionally, 8 - 16 nanorods with different diameters form a nanorod group, and n nanorod groups form a nanorod array structure, where n is a positive integer greater than or equal to 1.

[0024] Optionally, the nanocolumn group has different structural dimensions to match lights of different wavelengths.

[0025] Optionally, the nanoarray structure is one of an axisymmetric uniform phase structure, a single helical orbital angular momentum structure, or an eight helical orbital angular momentum structure.

[0026] Optionally, the prepared silicon-based superlens can be used as a repeating unit and extended and combined in a two-dimensional plane to form a wafer-level superlens array with a maximum diameter of 20 cm.

[0027] Another embodiment of the present application provides that the manufacturing method of the silicon-based superlens further includes: A first optical antireflection and antireflection enhancement layer, the first optical antireflection and antireflection enhancement layer is located on the first surface of the silicon-based superlens, and the optical antireflection and antireflection enhancement layer located on the first surface wraps the nanocolumn array structure.

[0028] Optionally, the manufacturing method of the silicon-based superlens further includes: A second optical antireflection and antireflection enhancement layer, the second optical antireflection and antireflection enhancement layer is located on the second surface of the silicon-based superlens.

[0029] Optionally, the first optical antireflection and antireflection enhancement layer is formed by atomic layer deposition.

[0030] Optionally, the first optical antireflection and antireflection enhancement layer is a zinc sulfide thin film.

[0031] Optionally, the second optical antireflection and antireflection enhancement layer is formed by thermal evaporation, electron beam evaporation, or atomic layer deposition.

[0032] Optionally, the second optical antireflection and antireflection enhancement layer is a single-layer or multi-layer composite film formed by one or more of germanium, zinc sulfide, and ytterbium fluoride.

[0033] To achieve the above and other purposes, the present application also provides a silicon-based superlens including: A substrate; A plurality of trenches are etched on the substrate, so as to form a nanocolumn array structure on the substrate; a silicon-based superlens is formed.

[0034] Optionally, the substrate is float zone single crystal silicon, the refractive index range of the float zone single crystal silicon is 3.4 to 3.6, and the resistivity range of the float zone single crystal silicon is 1000 to 20000 Ω·cm.

[0035] Optionally, the geometric shape of the nanocolumn is one of a silicon column, an elliptical column, a square column, and a triangular prism.

[0036] Optionally, the height of the nanocolumn is 10 μm to 15 μm.

[0037] Optionally, the minimum diameter of the nanocolumn ranges from 0.5 μm to 0.6 μm, and the maximum diameter ranges from 2 μm to 4 μm.

[0038] Optionally, the center spacing of the nanocolumns is 2.6 μm to 5.2 μm.

[0039] Optionally, the maximum aspect ratio of the nanocolumn is greater than 30:1.

[0040] Optionally, 8 - 16 nanocolumns with different diameters form a nanocolumn group, and n nanocolumn groups form a nanocolumn array structure, where n is a positive integer greater than or equal to 1.

[0041] Optionally, the nanocolumn group has different structural dimensions to match light of different wavelengths.

[0042] Optionally, the nanoarray structure is one of an axisymmetric uniform phase structure, a single - helix orbital angular momentum structure, or an eight - helix orbital angular momentum structure.

[0043] Optionally, the prepared silicon - based superlens can be used as a repeating unit to extend and combine in a two - dimensional plane into a wafer - level superlens array with a maximum diameter of 20 cm.

[0044] Optionally, the silicon - based superlens further includes: A first optical antireflection and antireflection enhancement layer, which is located on the first surface of the silicon - based superlens, and the optical antireflection and antireflection enhancement layer on the first surface wraps the nanocolumn array structure.

[0045] Optionally, the silicon - based superlens further includes: A second optical antireflection and antireflection enhancement layer, which is located on the second surface of the silicon - based superlens.

[0046] Optionally, the first optical antireflection and antireflection enhancement layer is a zinc sulfide thin film.

[0047] Optionally, the second optical antireflection and antireflection enhancement layer is a single - layer or multi - layer composite film formed by one or more of germanium, zinc sulfide, and ytterbium fluoride.

[0048] A silicon - based superlens and its manufacturing method provided by the present application set a series of periodic nanostructure units with a high aspect ratio on a substrate. By constructing a quantization model of the geometric parameters and phase response of the cylinder array structure unit, the phase control of electromagnetic waves in the radiation band of the atmospheric window is realized.

[0049] Furthermore, a silicon-based superlens and its manufacturing method provided by the present application can significantly improve the etching uniformity, reduce the sidewall roughness of structural units, and enhance the accuracy of phase regulation of silicon nanocolumns by optimizing the sidewall perpendicularity of lithography patterns, adjusting the gas flow distribution, increasing the number of etching cycles, and prolonging the duration ratio of the sidewall passivation phase in a single cycle. The wafer-level manufacturing method of this superlens has the advantages of good uniformity, simple process flow, and easy large-area manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Through the following description of the embodiments of the present application with reference to the accompanying drawings, the above and other objects, features, and advantages of the present application will become clearer. In the drawings: Figures 1a - 1e It is the wafer-level process manufacturing flow of a silicon-based superlens according to the present invention.

[0051] Figure 2 It is the schematic diagram of the geometric structure of an eight-level superlens according to the present invention.

[0052] Figures 3a - 3d It is the physical diagram and different structural design diagrams of a silicon-based superlens according to the present invention.

[0053] Figure 4 It is the array structure diagram of a silicon-based superlens according to the present invention.

[0054] Figure 5 It is the cross-sectional view of a silicon-based superlens according to the present invention.

[0055] Figure 6 It is the perspective view of a silicon-based superlens according to the present invention.

[0056] Figures 7a - 7c It is the manufacturing process of the front and back optical antireflection and antireflective coatings of a silicon-based superlens according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] The various embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. In each drawing, the same or similar reference numerals are used for the same elements. For clarity, the various parts in the drawings are not drawn to scale. In addition, some well-known parts may not be shown. For simplicity, a semiconductor structure obtained after several steps may be described in one drawing.

[0058] Unless otherwise defined, all technical and scientific terms used in the present disclosure have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the description of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used in the present disclosure includes any and all combinations of one or more of the related listed items.

[0059] The following further describes in detail the specific implementation manners of the present disclosure in conjunction with the accompanying drawings and embodiments.

[0060] Figures 1a to 1e A cross-sectional schematic diagram of a silicon-based superlens in each step according to an embodiment of the present application is shown.

[0061] As Figure 1a shown, a substrate 100 is provided.

[0062] Exemplarily, the substrate is selected as an 8-inch high-resistivity zone-melted single-crystalline silicon wafer with a resistivity > 1000 Ω·cm, a (100) crystal plane, a thickness of 600 - 750 μm, and double-sided polishing, and is cleaned and reserved for use.

[0063] As Figure 1b shown, a photoresist mask barrier layer 200 is provided on the surface of the substrate 100.

[0064] Exemplarily, UV135G with a thickness of 1.3 μm is selected as the photoresist mask barrier layer before etching in this experiment.

[0065] Furthermore, a 600 Å bottom anti-reflection coating (BARC, DUV44 - 6) needs to be spin-coated first before spin-coating the photoresist to reduce ultraviolet reflection and improve the photoresist morphology.

[0066] As Figure 1c shown, photolithography is performed on the photoresist mask barrier layer 200 on the surface of the substrate 100 to form a nano-column pattern 300.

[0067] Exemplarily, a deep ultraviolet DUV lithography machine of Nikon or Canon is used to set lithography parameters with an exposure energy of 240 - 280 mJ / cm2 and a focal length of 0 - (-0.6) μm. After development, a photoresist pattern of periodic nanostructure units is obtained on the silicon substrate, where the structural units of the photoresist are cylinders, and the side walls thereof need to satisfy a vertical angle of 85 - 90° with the silicon substrate.

[0068] As Figure 1d shown, deep silicon etching is performed on the substrate and the nano-column pattern 300, and a plurality of grooves are etched on the surface of the substrate 100, thereby forming a nano-column array structure 400 on the substrate.

[0069] Exemplarily, the photoresist pattern is transferred onto the silicon substrate through the Bosch deep trench etching process to form silicon nanocylinder structural units of different sizes. First, a BARC of 600 Å is etched away by a mixed gas of C4F8 and O2 in a certain proportion to expose the silicon substrate surface. Secondly, in the process parameter setting of the main etching step, the etching selectivity between the photoresist and the substrate silicon wafer needs to be optimized according to the etching depth, and the etching uniformity and the sidewall roughness of the cylindrical structural units need to be considered. To improve the etching uniformity, the flow distribution of the etching gas at the center and the edge of the wafer needs to be adjusted to improve the gradient uniformity of the etching gas distribution: the protective gas is selected as C4F8, and the gas flow rates at the center and the edge are set to 150 and 70 sccm respectively, and the powers at the center and the edge corresponding to the SRF inductive self-resonant frequency are set to 1800 W and 500 W respectively; the etching gas is selected as SF6, and the gas flow rates at the center and the edge are set to 300 and 50 sccm respectively, and the powers at the center and the edge corresponding to the SRF inductive self-resonant frequency are set to 2200 W and 600 W respectively. To reduce the sidewall roughness of the cylindrical structural units, in the present invention, the single-cycle time is compressed to ≤3 seconds, the number of etching cycles is increased to 250 times and above, and the proportion of the sidewall passivation phase duration in a single cycle is extended to ≥50%, that is, the residence time of the protective gas is 1.5 - 1.6 seconds, and the residence time of the etching gas is 1.4 - 1.5 seconds. The chamber pressure during etching is set to 30 mtorr.

[0070] Furthermore, the structural dimensions of the nanocolumn group can be optimized for light of different wavelengths.

[0071] Furthermore, Figure 2 For the first silicon-based superlens structure, a maximum of 8 levels of phase are adopted, the total etching depth is 12 μm, the minimum diameter of the nanocolumn group is 0.56 μm, the maximum diameter is 2.04 μm, and the period (center distance between cylinders) is 2.6 μm. Furthermore, the diameters of the individual nanocolumns in the nanocolumn group are 0.56 μm, 0.92 μm, 1.16 μm, 1.36 μm, 1.56 μm, 1.72 μm, 1.88 μm, 2.04 μm.

[0072] Furthermore, for the second silicon-based superlens structure, a maximum of 16 levels of phase are adopted, the total etching depth is 13.5 μm, the minimum diameter of the nanocolumn group is 0.5 μm, the maximum diameter is 3 μm, and the period (center distance between cylinders) is 4 μm.

[0073] Furthermore, the diameters of the individual nanocolumns in the nanocolumn group are 0.5 μm, 0.74 μm, 0.96 μm, 1.24 μm, 1.4 μm, 1.56 μm, 1.7 μm, 1.84 μm, 1.98 μm, 2.12 μm, 2.26 μm, 2.4 μm, 2.54 μm, 2.7 μm, 2.84 μm, 3 μm.

[0074] Furthermore, for the silicon-based metalens structure III, a maximum of 16 levels of phase are adopted, the total etching depth is 15 μm, the minimum diameter of the nano-pillar group is 0.6 μm, the maximum diameter is 4 μm, and the period (center distance between cylinders) is 5.2 μm.

[0075] Furthermore, the diameters of the individual nano-pillars in the nano-pillar group are 0.6 μm, 0.88 μm, 1.06 μm, 1.48 μm, 1.82 μm, 2.02 μm, 2.24 μm, 2.42 μm, 2.6 μm, 2.8 μm, 2.96 μm, 3.12 μm, 3.4 μm, 3.58 μm, 3.76 μm, and 4 μm.

[0076] Furthermore, the above etching parameters can achieve a height and diameter uniformity of the cylindrical structural unit > 95% and a reduction of the height difference of the corrugations on the cylindrical sidewall to ≤ 10 nm on an 8-inch wafer-level silicon wafer.

[0077] As Figure 1e shown, a silicon-based metalens is formed by removing the photoresist mask barrier layer 200 above the nano-pillar array structure 400.

[0078] Figures 3a - 3d These are different structure diagrams of the silicon-based metalens provided in this embodiment.

[0079] As Figure 3a described, this is a physical diagram of the actually fabricated metalens of this application.

[0080] Furthermore, as Figure 3b described, this is a structural design of the silicon-based metalens provided in this application, which is an axisymmetric uniform phase structure Figure 3a obtained from the design drawing according to Figure 3b .

[0081] Furthermore, as Figure 3c described, this is another structural design of the silicon-based metalens provided in this application, which is a single spiral orbital angular momentum structure.

[0082] Furthermore, as Figure 3d described, this is another structural design of the silicon-based metalens provided in this application, which is an eight spiral orbital angular momentum structure.

[0083] Figure 4 This is the structure diagram of the silicon-based metalens array of this application.

[0084] Exemplarily, by extending and combining the provided silicon-based metalens as a repeating unit on a two-dimensional plane, a large-sized silicon-based metalens can be obtained on an 8-inch wafer with a diameter of 20 cm.

[0085] Figure 5 This is the cross-sectional view of the silicon-based metalens of this application.

[0086] Figure 6 This is an oblique view of the silicon-based superlens of the present application.

[0087] Figures 7a to 7c Shows a cross-sectional schematic diagram of the silicon-based superlens of another embodiment of the present application at various steps.

[0088] As Figure 7b described, a first optical antireflection and antireflection enhancement thin film 500 is provided on the nano-column array structure 400.

[0089] Exemplarily, on the first surface of the superlens having a high aspect ratio periodic nano-array structure, by atomic layer deposition technology (ALD), using diethylzinc (DEZ) and hydrogen sulfide (H2S) as precursors, atomic-level uniform coating of the ZnS thin film on the high aspect ratio nano-silicon columns is achieved at 150 - 200 °C.

[0090] Further, the specific process parameters are as follows: The superlens substrate is heated to 180 °C, a DEZ pulse is introduced for 0.1 s, and then nitrogen is purged for 15 s to remove unadsorbed DEZ residues. A H2S pulse is introduced for 0.2 s, and nitrogen is purged for 20 s to remove unreacted H2S residues on the surface, completing a single cycle (growth rate 0.12 nm / cycle). Repeat 3000 - 5000 cycles to obtain a ZnS film with a thickness of 360 - 600 nm.

[0091] As Figure 7c described, a second optical antireflection and antireflection enhancement thin film 600 is provided on the second surface of the substrate 100.

[0092] Exemplarily, the back surface of the superlens is an unstructured polished surface, and the optical antireflection and antireflection enhancement film layer is formed by thermal evaporation or electron beam evaporation or atomic layer deposition. The thin film material can be selected from one, two, or three of Ge, ZnS, and YbF3. When Ge is deposited on the silicon wafer surface by electron beam evaporation, the deposition rate of Ge can be set to 3 - 4 Å / s. When ZnS and YbF3 are deposited on the silicon wafer surface by thermal evaporation, the deposition rate of ZnS can be set to 2.5 - 3.0 Å / s, and the deposition rate of YbF3 can be set to 1.5 - 2 Å / s. The temperature of the equipment cavity during evaporation can be set to 80 - 220 °C, and the Ar plasma purge mode of the equipment can be turned on during the evaporation of YbF3 or ZnS to increase the adhesion of the film layer.

[0093] Further, if a single thin film material of ZnS is selected as the optical antireflection and antireflection enhancement film, a ZnS thin film with a total evaporation thickness of 2 μm is deposited on the back surface of the unstructured silicon substrate.

[0094] Furthermore, if two thin film materials, Ge and ZnS, are selected as the antireflection composite film, the total evaporation thickness of the back side of the unstructured silicon substrate is 2 μm, where the thickness of Ge is 0.8 - 1 μm and the thickness of ZnS is 1 - 1.2 μm.

[0095] Furthermore, if three thin film materials, Ge, ZnS, and YbF3, are selected to be alternately deposited in a gradient refractive index combination to form the antireflection composite film, the total evaporation thickness of the back side of the unstructured silicon substrate is 2.2 μm, and 0.06 μm of Ge, 0.28 μm of ZnS, 0.16 μm of Ge, 0.64 μm of ZnS, 0.86 μm of YbF3, and 0.2 μm of ZnS are deposited in sequence to further improve the optical transmission efficiency.

[0096] As described above according to the embodiments of the present application, these embodiments do not describe all the details in detail, nor do they limit the application to only the specific embodiments described. Obviously, many modifications and variations can be made according to the above description. The present specification selects and specifically describes these embodiments to better explain the principle and practical application of the present application, so that those skilled in the art can make good use of the present application and its modifications based on the present application. The present application is only limited by the claims and their full scope and equivalents.

Claims

1. A manufacturing method of a silicon-based superlens, characterized in that, Comprising: Providing a substrate; Setting a photoresist pattern layer on the substrate; By etching the photoresist pattern layer and the substrate, a number of trenches are etched in the area of the substrate surface not protected by the photoresist pattern layer, and the trenches extend from the substrate surface into the substrate, thereby forming a nano-pillar array structure on the substrate; Removing the photoresist pattern layer to form a silicon-based superlens.

2. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that The substrate is float-zone single-crystalline silicon, the refractive index range of the float-zone single-crystalline silicon is 3.4 - 3.6, and the resistivity range of the float-zone single-crystalline silicon is 1000 - 20000 Ω·cm.

3. The manufacturing method of the silicon-based superlens according to claim 1, wherein, The photoresist pattern layer is formed by deep ultraviolet lithography through a photoresist mask barrier layer.

4. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, A bottom anti-reflection coating is set before setting the photoresist mask barrier layer.

5. The manufacturing method of the silicon-based superlens according to claim 3, characterized in that, The exposure dose of the lithography process is 250 ± 30 mJ / cm 2 , and the focal plane offset is 0 ± 0.6 μm.

6. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The etching process is a dry etching process with a high aspect ratio.

7. The manufacturing method of the silicon-based superlens according to claim 6, wherein The dry etching process with a high aspect ratio is carried out by pulsed etching with alternating cycles of C4F8 / SF6 gas.

8. The manufacturing method of the silicon-based superlens according to claim 6, wherein, In the dry etching process with a high aspect ratio, the single gas cycle time ≤ 3 seconds.

9. The manufacturing method of the silicon-based superlens according to claim 6, characterized in that, In the dry etching process with a high aspect ratio, the flow rate ratio of the sidewall passivation gas to the bottom etching gas in a single cycle is greater than 2 / 3.

10. The manufacturing method of the silicon-based superlens according to claim 6, characterized in that, In the dry etching process with a high aspect ratio, the ratio of the sidewall passivation process duration to the bottom etching process duration in a single cycle ≥ 1.

11. The manufacturing method of the silicon-based superlens according to claim 6, characterized in that, In the dry etching process with a high aspect ratio, the number of cycles ≥ 220 times.

12. The manufacturing method of the silicon-based superlens according to claim 1, wherein The geometric shape of the nano-pillars is one of silicon pillars, elliptical cylinders, square pillars, and triangular prisms.

13. The manufacturing method of the silicon-based superlens according to claim 1, wherein The height of the nano-pillars is 10 μm - 15 μm.

14. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The minimum diameter range of the nano-pillars is 0.5 μm - 0.6 μm, and the maximum diameter range is 2 μm - 4 μm.

15. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The center spacing of the nano-pillars is 2.6 μm - 5.2 μm.

16. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The maximum aspect ratio of the nano-pillars is greater than 30:

1.

17. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The photoresist removal process is an oxygen plasma dry photoresist removal process.

18. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, 8 - 16 nano-pillars with different diameters form a nano-pillar group, and n nano-pillar groups form a nano-pillar array structure, where n is a positive integer greater than or equal to 1.

19. The manufacturing method of the silicon-based superlens according to claim 18, wherein, The nano-pillar groups have different structural dimensions to match light of different wavelengths.

20. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The nano-array structure is one of an axisymmetric uniform phase structure, a single spiral orbital angular momentum structure, or an eight-spiral orbital angular momentum structure.

21. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, The prepared silicon-based superlens can be used as a repeating unit to be extended and combined in a two-dimensional plane into a wafer-level superlens array with a maximum diameter of 20 cm.

22. The manufacturing method of the silicon-based superlens according to claim 1, wherein, Also comprising: A first optical anti-reflection and anti-reflection enhancement layer, the first optical anti-reflection and anti-reflection enhancement layer is located on the first surface of the silicon-based superlens, and the optical anti-reflection and anti-reflection enhancement layer located on the first surface wraps the nano-pillar array structure.

23. The manufacturing method of the silicon-based superlens according to claim 1, characterized in that, Also comprising: A second optical anti-reflection and anti-reflection enhancement layer, the second optical anti-reflection and anti-reflection enhancement layer is located on the second surface of the silicon-based superlens.

24. The manufacturing method of the silicon-based superlens according to claim 22, characterized in that, The first optical anti-reflection and anti-reflection enhancement layer is formed by atomic layer deposition.

25. The manufacturing method of the silicon-based superlens according to claim 22, characterized in that, The first optical anti-reflection and anti-reflection enhancement layer is a zinc sulfide thin film.

26. The manufacturing method of the silicon-based superlens according to claim 25, characterized in that, The second optical anti-reflection and anti-reflection enhancement layer is formed by thermal evaporation or electron beam evaporation or atomic layer deposition.

27. The manufacturing method of the silicon-based superlens according to claim 25, characterized in that, The second optical anti-reflection and anti-reflection enhancement layer is a single-layer or multi-layer composite film formed by one or more of germanium, zinc sulfide, and ytterbium fluoride.

28. A silicon-based superlens, characterized in that, Comprising: A substrate; A number of trenches are etched in the substrate, thereby forming a nano-pillar array structure on the substrate; Form a silicon-based superlens.

29. The silicon-based superlens according to claim 28, wherein The substrate is float-zone single-crystalline silicon, the refractive index range of the float-zone single-crystalline silicon is 3.4 - 3.6, and the resistivity range of the float-zone single-crystalline silicon is 1000 - 20000 Ω·cm.

30. The silicon-based superlens according to claim 28, wherein The geometric shape of the nanocolumn is one of a silicon column, an ellipsoidal column, a square column, and a triangular prism.

31. The silicon-based superlens according to claim 30, characterized in that, The height of the nanocolumn is 10 μm - 15 μm.

32. The silicon-based superlens according to claim 30, wherein, The minimum diameter range of the nanocolumn is 0.5 μm - 0.6 μm, and the maximum diameter range is 2 μm - 4 μm.

33. The silicon-based superlens according to claim 30, wherein, The center spacing of the nanocolumns is 2.6 μm - 5.2 μm.

34. The silicon-based superlens according to claim 30, wherein, The maximum aspect ratio of the nanocolumn is greater than 30:

1.

35. The silicon-based superlens according to claim 30, characterized in that, 8 - 16 nanocolumns with different diameters form a nanocolumn group, and n nanocolumn groups form a nanocolumn array structure, where n is a positive integer greater than or equal to 1.

36. The silicon-based superlens according to claim 30, wherein, The said nanocolumn group has different structural dimensions to match lights of different wavelengths.

37. The silicon-based superlens according to claim 28, characterized in that, The nanocolumn array structure is one of an axisymmetric uniform phase structure, a single helical orbital angular momentum structure, or an eight-helical orbital angular momentum structure.

38. The silicon-based superlens according to claim 28, wherein, The prepared silicon-based superlens can be used as a repeating unit to extend and combine in a two-dimensional plane to form a wafer-level superlens array with a maximum diameter of 20 cm.

39. The silicon-based superlens according to claim 28, wherein It also includes: A first optical antireflection and antireflection enhancement layer, which is located on the first surface of the silicon-based superlens, and the optical antireflection and antireflection enhancement layer on the first surface wraps the nanocolumn array structure.

40. The silicon-based superlens according to claim 28, wherein It also includes: A second optical antireflection and antireflection enhancement layer, which is located on the second surface of the silicon-based superlens.

41. The silicon-based superlens according to claim 39, characterized in that, The first optical antireflection and antireflection enhancement layer is a zinc sulfide thin film.

42. The silicon-based superlens according to claim 40, wherein The second optical antireflection and antireflection enhancement layer is a single-layer or multi-layer composite film formed by one or more of germanium, zinc sulfide, and ytterbium fluoride.

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