Manufacturing method of optical fiber super-structure lens and optical fiber super-structure lens

Abstract

The invention provides a manufacturing method of an optical fiber super-structure lens and the optical fiber super-structure lens, and the method comprises the steps: arranging a lens substrate on an optical fiber insertion core fixing base, enabling the optical fiber insertion core fixing base to be provided with an optical fiber insertion core limiting hole, enabling the optical fiber insertion core limiting hole to contain an optical fiber insertion core, and enabling the optical fiber insertion core to be provided with an optical fiber transmission channel; performing white light irradiation on the optical fiber transmission channel along the extension direction of the optical fiber transmission channel to form a white light path for propagation in the optical fiber transmission channel, and determining a white light emitting area for emitting light on the lens substrate based on the white light path; and forming a lens nano structure corresponding to the same area on one side, far away from the optical fiber ferrule fixing base, of the lens substrate based on the white light emitting area.

Description

Technical Field

[0001] The present invention relates to semiconductor technology, and in particular to a method for manufacturing an optical fiber meta-lens and an optical fiber meta-lens. Background Art

[0002] The semiconductor industry is gradually entering the post-Moore era, and high-computing-power and low-power photonic chips and photonic sensors have emerged. As an important transmission medium, optical fiber builds a bridge for the conversion of optical and electrical signals, and its efficient, high-reliability, and low-cost integration with planar chips has important research value.

[0003] The essence of vertical coupling between optical fiber and silicon photonic chip is that the optical fiber and chip waveguide are in a mutually perpendicular positional relationship based on the integration of the optical fiber and silicon photonic chip, and the light waves are coupled between the optical fiber and chip waveguide through the diffraction effect of the chip surface.

[0004] Secondly, with the rapid development of micro-nano optics represented by subwavelength nanostructured metasurfaces / superlenses, planar superlenses have gradually replaced traditional bulky lenses with large volume, small numerical aperture, and single functions and become the mainstream of research and industrialization hotspots. A typical example is the fiber superlens with subwavelength nanostructure arrays integrated on the fiber end face. Due to the compatibility of MEMS technology with fiber end processing technology, it is usually integrated with the fiber after the superlens is prepared in a planar manner. In order to ensure the precise coupling of the fiber output light and the superlens, high requirements are placed on the vertical integration accuracy and stability of the fiber and the planar superlens. Summary of the invention

[0005] Based on the above problems, the present invention is proposed to provide a method for manufacturing a fiber metalens and a fiber metalens that overcome the above problems or at least partially solve the above problems.

[0006] According to one aspect of the present invention, a method for manufacturing a fiber meta-lens is provided, comprising the following steps: A lens substrate is arranged on a fiber optic ferrule fixing base, wherein the fiber optic ferrule fixing base is provided with a fiber optic ferrule limiting hole, and the fiber optic ferrule limiting hole accommodates the fiber optic ferrule, wherein the fiber optic ferrule has a fiber optic transmission channel; irradiating the optical fiber transmission channel with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and determining a white light emitting area from the lens substrate based on the white light path; Based on the white light emitting area, a lens nanostructure corresponding to the same area is formed on a side of the lens substrate away from the optical fiber ferrule fixing base.

[0007] Optionally, in the method according to the present invention, irradiating the optical fiber transmission channel with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and determining a white light emission area emitted from the lens substrate based on the white light path, comprising: Spin coating photoresist on the side of the lens substrate away from the optical fiber ferrule fixing base to obtain a photoresist layer; The optical fiber transmission channel is irradiated with white light along the extension direction of the optical fiber transmission channel to form a white light path that propagates in the optical fiber transmission channel, and the photoresist layer is exposed and developed based on the white light path to form a substrate shielding portion corresponding to the white light emitting area on the lens substrate.

[0008] Optionally, in the method according to the present invention, spin coating of photoresist is performed on a side of the lens substrate away from the optical fiber ferrule fixing base, and the obtained photoresist layer is cured, comprising: Performing a first spin coating operation based on photoresist at a preset first spin coating speed for a preset first spin coating time on a side of the lens substrate away from the optical fiber ferrule fixing base; After the first spin coating operation is completed, a second spin coating operation based on photoresist is performed on a side of the lens substrate away from the optical fiber ferrule fixing base at a preset second spin coating speed for a preset second spin coating time; Performing a pre-baking treatment on the photoresist layer obtained based on the first spin coating operation and the second spin coating operation at a preset first baking temperature for a preset first baking time; After the pre-baking treatment is completed, the photoresist layer is subjected to a mid-baking treatment at a preset second baking temperature for a preset second baking time; After the intermediate baking process is completed, the photoresist layer is subjected to a post-baking process at a preset third baking temperature for a preset third baking time to complete the curing of the photoresist layer.

[0009] Optionally, in the method according to the present invention, based on the white light emitting area, a lens nanostructure corresponding to the same area is formed on a side of the lens substrate away from the optical fiber ferrule fixing base, comprising: Based on the base shielding portion, the lens base is away from the side of the optical fiber ferrule fixing base. Etching the remaining area except the white light emitting area to reduce the thickness of the remaining area, thereby forming a substrate step located on the lens substrate and corresponding to the same area as the white light emitting area; Depositing an a-Si:H thin film on the side of the lens substrate away from the optical fiber ferrule fixing base to obtain an a-Si:H thin film layer; The a-Si:H thin film layer is imaged to obtain a lens nanostructure.

[0010] Optionally, in the method according to the present invention, the step of obtaining the a-Si:H thin film layer further comprises: The method of obtaining the a-Si:H thin film layer further comprises: A Cartesian coordinate system is established based on the a-Si:H thin film layer, a tangent line 1 having a tangent relationship with the contour of the a-Si:H thin film layer is established, and a tangent point A corresponding to the tangent line 1 is obtained; Establishing a tangent line 2 which is parallel to the tangent line 1 and has a tangent relationship with the profile of the a-Si:H thin film layer, and obtaining a tangent point B corresponding to the tangent line 2, wherein the tangent line 1 and the tangent line 2 do not overlap; The first point coordinates and the second point coordinates corresponding to the tangent point A and the tangent point B are determined based on the Cartesian coordinate system, and the center coordinate point of the corresponding a-Si:H thin film layer is determined based on the first point coordinates and the second point coordinates.

[0011] Optionally, in the method according to the present invention, the a-Si:H thin film layer is subjected to image processing to obtain a lens nanostructure, comprising: Spin coating electron beam glue on the side of the a-Si:H thin film layer away from the lens substrate, and patterning the obtained electron beam glue layer to obtain a sub-wavelength nanostructure corresponding to the white light emitting area and a thin film shielding portion corresponding to the remaining area; Performing Cr-based thin film deposition on a side of the lens substrate away from the optical fiber ferrule fixing base to obtain a Cr thin film layer; The Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure are peeled off to obtain a Cr nanostructure corresponding to the white light emitting area; Etching the a-Si:H thin film layer to obtain a composite nanostructure corresponding to the white light emitting area, wherein the composite nanostructure includes an a-Si:H nanostructure located on the substrate step and a Cr nanostructure located on the a-Si:H nanostructure; The Cr nanostructure is removed to obtain a lens nanostructure consisting of the substrate step and the a-Si:H nanostructure.

[0012] Optionally, in the method according to the present invention, the Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure are peeled off, comprising: The lens substrate is placed in an acetone solution corresponding to a preset solution temperature, and the Cr film layer, the electron beam gel layer, and the sub-wavelength nanostructure on the lens substrate are peeled off based on ultrasound.

[0013] Optionally, in the method according to the present invention, removing the Cr nanostructure comprises: The Cr nanostructure is rinsed with an etching solution formed by mixing ammonium cerium nitrate, glacial acetic acid and deionized water.

[0014] Optionally, in the method according to the present invention, etching the a-Si:H thin film layer to obtain a composite nanostructure corresponding to the white light emitting region comprises: The a-Si:H thin film layer is subjected to gas etching using SF6 etching gas to obtain a composite nanostructure corresponding to the white light emitting region.

[0015] According to another aspect of the present invention, there is provided a fiber metalens manufactured based on the manufacturing method of the fiber metalens, comprising: Lens substrates and lens nanostructures; Wherein, the lens substrate is arranged on an optical fiber fixing base, and the lens nanostructure is arranged on a side of the lens substrate away from the optical fiber core fixing base.

[0016] According to the solution of the present invention, the present invention successfully prepares an optical fiber meta-lens with high-precision nanostructure by setting a lens substrate on a fiber optic core fixing base and determining the white light emitting area on the lens substrate based on the white light optical path. The method ensures the precise alignment and efficient light transmission of the nanostructure through adaptive exposure technology, and significantly improves the coupling efficiency between the optical fiber and the lens. Specifically, the formation of the lens nanostructure is based on the adaptive exposure of the white light optical path, which avoids the light transmission loss caused by alignment errors in traditional processes and improves the performance of optical devices. In addition, the invention ensures the high precision and large-area uniformity of the nanostructure through processes such as spin coating, exposure, development, thin film deposition, and etching of photoresist, improves the preparation efficiency and consistency, and is suitable for the integrated application of high-precision optical devices and photonic chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A flow chart showing a method for manufacturing a fiber meta-lens according to an embodiment of the present invention is shown; Figure 2-Figure 14 A manufacturing process diagram of each sub-step of the manufacturing method of the corresponding optical fiber meta-lens in this embodiment is shown; Fig.15 A physical diagram of the optical fiber ferrule fixing base in this embodiment is shown; Fig.16 A physical diagram showing that the lens substrate and the optical fiber ferrule fixing base in this embodiment are integrally formed based on femtosecond laser bonding; Fig.17An interface diagram of femtosecond laser bonding of a lens base and an optical fiber ferrule fixing base in this embodiment is shown; Fig.18 A physical diagram of the optical fiber ferrule fixed on the optical fiber ferrule fixing base in this embodiment is shown; Fig.19 The microscope result diagram showing the white light emitting area in this embodiment is formed on the side of the lens substrate away from the optical fiber ferrule fixing base and corresponding to the same area; Fig. 20 The microscope result image of the substrate step corresponding to the white light emitting area in the present embodiment is shown; Fig.21 The microscope result diagram showing the coincidence of the center of the substrate step and the center of the lens using the "parallel line tangent point centering method" in this embodiment is shown; Fig. 22 The SEM image of the corresponding lens nanostructure in this embodiment is shown. DETAILED DESCRIPTION

[0018] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0019] In order to solve the problems existing in the above-mentioned background technology, an embodiment of the present invention provides a method for manufacturing a fiber meta-lens.

[0020] Figure 1 FIG. 1 is a flow chart showing a method for manufacturing a fiber meta-lens according to an embodiment of the present invention. Figure 1 As shown, the manufacturing method of the optical fiber metalens proposed in this embodiment begins with step S101. In step S101, the following contents are included: A lens substrate is arranged on a fiber optic ferrule fixing base, wherein the fiber optic ferrule fixing base is provided with a fiber optic ferrule limiting hole, and the fiber optic ferrule is accommodated in the fiber optic ferrule limiting hole, wherein the fiber optic ferrule has a fiber optic transmission channel.

[0021] For example, in this embodiment, Figure 2As shown, the corresponding optical fiber ferrule fixing base is provided with a corresponding optical fiber ferrule through a corresponding optical fiber ferrule limiting hole, wherein the optical fiber ferrule is mainly used for the optical fiber unit to be inserted, so that the optical data output by the optical fiber unit can be transmitted in the optical fiber ferrule fixing base, and the lens substrate arranged on the optical fiber ferrule fixing base is used to form a corresponding lens nanostructure in a subsequent step, so that the optical data can be further transmitted based on the lens nanostructure. Furthermore, in order to achieve corresponding fixation between the optical fiber ferrule and the optical fiber ferrule fixing base, it can be fixed based on a corresponding high-temperature adhesive layer.

[0022] In step S102, the following contents are included: The optical fiber transmission channel is irradiated with white light along its extension direction to form a white light path propagating in the optical fiber transmission channel, and a white light emitting area emitting from the lens substrate is determined based on the white light path.

[0023] For example, in this embodiment, in order to form a lens nanostructure for transmitting optical data based on a lens substrate, it is necessary to determine the transmission range of the corresponding optical data. Therefore, the optical fiber transmission channel can be irradiated with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and the white light emission area where the white light path is emitted from the lens substrate can be further determined.

[0024] Further, in this embodiment, the above-mentioned “irradiating the optical fiber transmission channel with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and determining a white light emitting area for emitting from the lens substrate based on the white light path” may also include the following steps: Spin coating photoresist on the side of the lens substrate away from the optical fiber ferrule fixing base, and curing the obtained photoresist layer; The optical fiber transmission channel is irradiated with white light along the extension direction of the optical fiber transmission channel to form a white light path that propagates in the optical fiber transmission channel, and the photoresist layer is exposed and developed based on the white light path to form a substrate shielding portion corresponding to the white light emitting area on the lens substrate.

[0025] For example, in this embodiment, Figure 3 as well as Figure 4As shown, in order to determine the corresponding white light emitting area on the lens substrate, the corresponding photoresist can be firstly spin-coated on the side of the lens substrate away from the optical fiber core fixing base to form a corresponding photoresist layer, and further form a white light path propagating in the optical fiber transmission channel, and the photoresist layer is exposed and developed based on the white light path to form a substrate shielding portion corresponding to the white light emitting area on the lens substrate, so that the area corresponding to the substrate shielding portion corresponds to the white light emitting area, so that the corresponding lens nanostructure can be subsequently formed on the lens substrate based on the white light emitting area.

[0026] Furthermore, in this embodiment, the above-mentioned “spin coating the photoresist on the side of the lens substrate away from the optical fiber ferrule fixing base, and curing the obtained photoresist layer” may also include the following steps: Performing a first spin coating operation based on photoresist at a preset first spin coating speed for a preset first spin coating time on a side of the lens substrate away from the optical fiber ferrule fixing base; After the first spin coating operation is completed, a second spin coating operation based on photoresist is performed on a side of the lens substrate away from the optical fiber ferrule fixing base at a preset second spin coating speed for a preset second spin coating time; Performing a pre-baking treatment on the photoresist layer obtained based on the first spin coating operation and the second spin coating operation at a preset first baking temperature for a preset first baking time; After the pre-baking treatment is completed, the photoresist layer is subjected to a mid-baking treatment at a preset second baking temperature for a preset second baking time; After the intermediate baking process is completed, the photoresist layer is subjected to a post-baking process at a preset third baking temperature for a preset third baking time to complete the curing of the photoresist layer.

[0027] For example, in this embodiment, during the formation of the photoresist layer, the following contents may be described: First, a first spin coating operation based on photoresist can be performed on a side of the lens substrate away from the optical fiber ferrule fixing base at a preset first spin coating speed for a preset first spin coating time; Next, after the corresponding first spin coating operation is completed, a second spin coating operation based on photoresist can be performed again at a preset second spin coating speed for a preset second spin coating time on the side of the lens substrate away from the optical fiber ferrule fixing base; Finally, after completing the corresponding first spin coating operation and the second spin coating operation in sequence, the obtained photoresist layer can be subjected to corresponding baking operations. Here, the baking operations are divided into pre-baking treatment, intermediate baking treatment and post-baking treatment. First, the photoresist layer can be subjected to pre-baking treatment at a preset first baking temperature for a preset first baking time. After completing the corresponding pre-baking treatment, the photoresist layer needs to be further subjected to intermediate baking treatment at a preset second baking temperature for a preset second baking time. After completing the corresponding intermediate baking treatment, the photoresist layer needs to be subjected to post-baking treatment at a preset third baking temperature for a preset third baking time again, thereby completing the curing of the photoresist layer.

[0028] In step S103, the following contents are also included: Based on the white light emitting area, a lens nanostructure corresponding to the same area is formed on a side of the lens substrate away from the optical fiber ferrule fixing base.

[0029] For example, in this embodiment, after the corresponding white light emission area is determined, a lens nanostructure corresponding to the same area can be further formed on the side of the lens substrate away from the optical fiber ferrule fixing base based on the white light emission area, so that when the subsequent optical fiber unit is inserted into the optical fiber ferrule, the optical data output by the optical fiber unit can be transmitted in integrity based on the lens nanostructure.

[0030] Furthermore, in this embodiment, the above-mentioned “forming a lens nanostructure corresponding to the same area on the side of the lens substrate away from the optical fiber ferrule fixing base based on the white light emitting area” may also include the following contents: Based on the base shielding portion, the lens base is away from the side of the optical fiber ferrule fixing base. Etching the remaining area except the white light emitting area to reduce the thickness of the remaining area, thereby forming a substrate step located on the lens substrate and corresponding to the same area as the white light emitting area; Depositing an a-Si:H thin film on the side of the lens substrate away from the optical fiber ferrule fixing base to obtain an a-Si:H thin film layer; The a-Si:H thin film layer is imaged to obtain a lens nanostructure.

[0031] For example, in this embodiment, based on the above content, after the photoresist layer is exposed and developed, Figure 5 As shown, a base shielding portion corresponding to the white light emitting area can be formed, and then a lens nanostructure corresponding to the base shielding portion can be formed through the following specific process: First, if Figure 6As shown, based on the substrate shielding portion, the remaining area of ​​the lens substrate away from the optical fiber ferrule fixing base, except for the white light emitting area, can be etched; this step is intended to reduce the thickness of the remaining area, thereby forming a substrate step on the lens substrate corresponding to the white light emitting area and having the same shape; Then, if Figure 7 As shown, on the side of the lens substrate away from the optical fiber ferrule fixing base, a thin film deposition operation based on amorphous silicon hydrogenation (a-Si:H) is performed to obtain a uniform a-Si:H thin film layer, wherein the specific thin film deposition operation can utilize PECVD equipment, the corresponding process gas used is SiH4 / Ar, and the deposition thickness is about 1μm; wherein the corresponding process parameters may include: SiH4 25sccm, Ar 475sccm, reaction pressure 100mTorr, and process temperature 150°C.

[0032] Furthermore, in this embodiment, the above-mentioned “obtaining an a-Si:H thin film layer” may further include the following steps: The method of obtaining the a-Si:H thin film layer further comprises: A Cartesian coordinate system is established based on the a-Si:H thin film layer, a tangent line 1 having a tangent relationship with the contour of the a-Si:H thin film layer is established, and a tangent point A corresponding to the tangent line 1 is obtained; Establishing a tangent line 2 which is parallel to the tangent line 1 and has a tangent relationship with the profile of the a-Si:H thin film layer, and obtaining a tangent point B corresponding to the tangent line 2, wherein the tangent line 1 and the tangent line 2 do not overlap; The first point coordinates and the second point coordinates corresponding to the tangent point A and the tangent point B are determined based on the Cartesian coordinate system, and the center coordinate point of the corresponding a-Si:H thin film layer is determined based on the first point coordinates and the second point coordinates.

[0033] For example, in this embodiment, in order to improve the position accuracy of the lens nanostructure in the actual production process, the center position corresponding to the a-Si:H thin film layer can be determined by the "parallel line tangent point centering method" to form the lens nanostructure based on the center position in the subsequent process, wherein the specific method steps include: First, the operation interface of the electron beam exposure equipment (which can also be established based on the a-Si:H thin film layer) can be positioned as a Cartesian coordinate system, with the up-down direction being the y-axis and the left-right direction being the x-axis; Next, add a tangent line 1 parallel to the Y axis in the operation interface, move the sample stage of the electron beam exposure equipment to make the left contour of the a-Si:H film layer tangent to the tangent line 1, and obtain the corresponding tangent point A(x1,y1) at the same time; Finally, based on the right contour of the a-Si:H thin film layer, a tangent line 2 parallel to the tangent line 1 can be drawn, and the tangent point B (x2, y2) can be found in the same way. At this time, the line connecting the tangent points A and B is the diameter, and the center of the line segment is the center position of the a-Si:H thin film layer.

[0034] It can be explained that this method is simple and accurate, while another method is often used in the prior art, such as obtaining the outer contour of the base a-Si:H thin film layer and finding the center point through a computer algorithm. This method requires making a new mark in the sample, selecting the mark as the origin of the coordinate system, obtaining the outer contour of the re-mark and the base step, and determining the relative position of the center of the base step and the mark through an algorithm. This method is complicated and was not adopted in this project.

[0035] In addition, in this embodiment, the above-mentioned “performing image processing on the a-Si:H thin film layer to obtain a lens nanostructure” may also include the following steps: Spin coating electron beam glue on the side of the a-Si:H thin film layer away from the lens substrate, and patterning the obtained electron beam glue layer to obtain a sub-wavelength nanostructure corresponding to the white light emitting area and a thin film shielding portion corresponding to the remaining area; Performing Cr-based thin film deposition on a side of the lens substrate away from the optical fiber ferrule fixing base to obtain a Cr thin film layer; The Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure are peeled off to obtain a Cr nanostructure corresponding to the white light emitting area; Etching the a-Si:H thin film layer to obtain a composite nanostructure corresponding to the white light emitting area, wherein the composite nanostructure includes an a-Si:H nanostructure located on the substrate step and a Cr nanostructure located on the a-Si:H nanostructure; The Cr nanostructure is removed to obtain a lens nanostructure consisting of the substrate step and the a-Si:H nanostructure.

[0036] Then, if Figure 8 as well as Fig. 9As shown, the electron beam glue is spin-coated on the side of the a-Si:H thin film layer away from the lens substrate; and the obtained electron beam glue layer is further patterned to form a sub-wavelength nanostructure corresponding to the white light emitting area, and a thin film shielding portion corresponding to the remaining area, wherein the material of the corresponding electron beam glue can be PMMA (specifically spin-coated PMMA, wherein the PMMA model can be 495A5, and the spin coating parameters are: 2000 rpm, 180°C hot plate baking for 1 min, and a target thickness of 300 nm); and for the patterning of the electron beam glue layer, an electron beam exposure machine can be used to modify the electron beam glue, and it can be dissolved based on the corresponding developer, wherein the exposure dose needs to be 1000 μC / cm2, the developer ratio MIBK:IPA=1:3, the development time is 40s, and the additional rinsing in IPA is 30s, thereby forming a sub-wavelength nanostructure corresponding to the white light emitting area, and a thin film shielding portion corresponding to the remaining area; Afterwards, if Fig.10 As shown, a chromium (Cr)-based thin film deposition is performed on the side of the lens substrate away from the optical fiber core fixing base (wherein the corresponding parameters of the thin film deposition may include: vacuum degree <10^-6Torr, metal Cr, thickness 30nm), to obtain a Cr thin film layer, wherein the deposition of the Cr thin film layer may be achieved by a magnetron sputtering process, and the thickness of the corresponding Cr thin film layer generally needs to be less than half of the thickness of the corresponding electron beam gel layer; Then, if Fig.11 As shown, the Cr thin film layer, the electron beam gel layer and the sub-wavelength nanostructure are subjected to a stripping treatment (wherein the stripping treatment may specifically include 65°C hot acetone ultrasound for 5 minutes, and then corresponding room temperature anhydrous ethanol ultrasound for 2 to 3 times) to retain the Cr nanostructure corresponding to the white light emitting area; Then, if Fig.12 As shown, the a-Si:H thin film layer is etched to remove the portion covered by the thin film shielding portion, thereby obtaining a composite nanostructure corresponding to the white light emitting area. The composite nanostructure includes an a-Si:H nanostructure located on the substrate step, and a Cr nanostructure located on the a-Si:H nanostructure; Finally, if Fig.13 As shown, the Cr nanostructure is removed to obtain a lens nanostructure composed of a substrate step and an a-Si:H nanostructure.

[0037] Furthermore, in this embodiment, the above-mentioned “peeling off the Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure” may also include the following steps: The lens substrate is placed in an acetone solution corresponding to a preset solution temperature, and the Cr film layer, the electron beam gel layer, and the sub-wavelength nanostructure on the lens substrate are peeled off based on ultrasound.

[0038] For example, in this embodiment, the preset solution temperature may correspond to 65°C.

[0039] Similarly, in this embodiment, the above-mentioned “removing the Cr nanostructure” may also include the following steps: The Cr nanostructure is rinsed with an etching solution formed by mixing ammonium cerium nitrate, glacial acetic acid and deionized water.

[0040] In addition, in this embodiment, the above-mentioned “etching the a-Si:H thin film layer to obtain a composite nanostructure corresponding to the white light emitting area” may further include the following steps: The a-Si:H thin film layer is subjected to gas etching using SF6 etching gas to obtain a composite nanostructure corresponding to the white light emitting region.

[0041] For example, in this embodiment, for the gas etching of the a-Si:H thin film layer, the corresponding SF6 can be used as the etching gas and the etching is performed based on ICP plasma, wherein the corresponding etching temperature is 23°C, the gas flow rate is 50sccm, the reaction pressure is 10mtorr, the RF Power is 40~60W, and the ICP Power is 700~800W. After the etching is completed, the remaining Cr mask can be further removed using a Cr etching solution (cerium ammonium nitrate: glacial acetic acid: water = 22:8:70), and the rinsing time is 2~5s.

[0042] Here, if Fig.14 As shown, after the formation of the corresponding lens nanostructure is completed, the corresponding optical fiber meta-lens can be obtained. If it needs to be used, the corresponding optical fiber monomer can be inserted into the corresponding optical fiber ferrule through the optical fiber transmission channel to abut the corresponding end of the optical fiber monomer against the lens base.

[0043] Furthermore, in order to prevent the optical fiber monomer from maintaining its position after being inserted into the optical fiber ferrule, the corresponding high-temperature ceramic glue can be used to bond the optical fiber monomer to the optical fiber transmission channel, and after the high-temperature ceramic glue completes the corresponding curing, the obtained optical fiber meta-lens needs to be naturally cooled accordingly.

[0044] It should be noted that after the formation of the lens nanostructure is completed based on the above method steps, since the structural parameters of the lens nanostructure determine the subsequent use effect, in order to determine whether the lens nanostructure is qualified, a corresponding evaluation process is required to ensure that the produced lens nanostructure has a good use effect; therefore, in this embodiment, the above-mentioned "forming a lens nanostructure corresponding to the same area on the side of the lens substrate away from the optical fiber ferrule fixing base based on the white light emitting area" can also include the following steps: Placing a test collection board on a side of the lens nanostructure away from the lens substrate, and irradiating the optical fiber transmission channel with light based on the test light along the extension direction of the optical fiber transmission channel; Controlling the acquisition unit to acquire images from the test acquisition board to obtain a test image corresponding to the test acquisition board; Performing pixel processing on the test image to obtain each image pixel constituting the test image, and obtaining each image pixel value corresponding to each image pixel; Compare each image pixel value with the retrieved test pixel interval of the corresponding test light, and determine all image pixel points whose corresponding image pixel values ​​are located in the test pixel interval as target pixel points; Connecting each target pixel point based on the point positions between adjacent positions to obtain each test area located in the test image and corresponding to each lens nano unit included in the lens nano structure; Calculate the mean value of each target pixel point constituting the same test area based on the pixel value to obtain the pixel value of each area corresponding to each test area; Comparing the pixel value of each region with the retrieved standard pixel value corresponding to the test light, and determining the length defect value corresponding to the lens nanostructure based on the comparison result; Obtaining the number of target pixels corresponding to each target pixel point constituting the same test area, and comparing each target pixel number with the retrieved standard pixel number corresponding to the test light, and determining the width defect value corresponding to the lens nanostructure based on the comparison result; The length defect value and the width defect value are summed and calculated, and the obtained comprehensive defect value is compared with the retrieved preset evaluation threshold; In response to the comprehensive defect value being less than the preset evaluation threshold, determining the lens nanostructure as qualified; In response to the comprehensive defect value being greater than or equal to the preset evaluation threshold, the lens nanostructure is determined to be unqualified.

[0045] For example, in this embodiment, when determining whether the structural parameters of the lens nanostructure meet the standards, the light transmittance of the lens nanostructure may be evaluated, and the corresponding process may be as follows: First, the corresponding test acquisition board can be set on the side of the lens nanostructure away from the lens substrate, and the channel can be irradiated with test light along the extension path of the optical fiber transmission channel. Here, the color of the test light can be preset, such as blue, yellow, red, etc.; Next, a collection unit (such as a camera) may be started to perform an image capture operation on the test collection board to obtain a test image associated with the test collection board. Here, it can be explained that since the lens nanostructure has the function of transmitting light data, when the test light is used to irradiate along the optical fiber transmission channel, the generated light data will be transmitted to the corresponding test collection board via the lens nanostructure. Therefore, after completing the image collection of the test collection board, an image area corresponding to the light data can be obtained on the test collection board; Next, pixel processing is performed on the captured test image to parse out the individual image pixels constituting the test image, and the image pixel value corresponding to each image pixel is collected; Afterwards, each image pixel value is compared with the pre-acquired test pixel interval of the corresponding test light one by one, and all image pixel points whose image pixel values ​​fall into the test pixel interval are identified and confirmed as target pixel points. Here, since the test light will produce a visual color change based on the structural length of the lens nanostructure (which can also be understood as the structural height of the corresponding lens nanostructure) during the propagation process, for example, the smaller the structural length, the greater the distance between the lens nanostructure and the test acquisition board, and the corresponding light area of ​​the corresponding test light collected by the test acquisition board will be darker, and when the structural length is longer, the lens nanostructure and the test acquisition board will be closer. The closer the distance between the boards is, the brighter the color of the light area corresponding to the test light collected by the test acquisition board will be. Therefore, in order to be able to identify all the light areas collected by the test acquisition board, the test pixel interval of the corresponding test light can be set, wherein the test pixel interval can be based on the test pixel value of the corresponding test light as the center value to generate a pixel area with a certain pixel range. For example, when the test pixel value is 100, the corresponding test pixel interval can be [95, 105]; that is, when the image pixel value corresponding to any image pixel point falls into the test pixel interval, it can be determined that the generation of the image pixel point is based on the irradiation of the test light; Then, according to the adjacent position relationship between each target pixel point, a point connection operation is performed, so as to define the test areas corresponding to each lens nano unit arranged in an array and included in the lens nano structure in the test image. Here, each test area can be understood as a light area formed on the test acquisition board when the test light is transmitted through different lens nano units during the transmission process; Then, for each test area, the average value of the pixel values ​​of each target pixel point constituting the area is calculated to obtain the area pixel value corresponding to each test area; Afterwards, the pixel value of each region is compared with the preset standard pixel value of the corresponding test light, and the length defect value of the lens nanostructure is evaluated and obtained according to the comparison result. Here, it can be explained that the standard pixel value can be understood as the pixel value corresponding to the light area that can be formed on the test acquisition board under the transmission effect of the test light when the structural parameters of the corresponding nanostructure unit are correct. When there is a deviation between the regional pixel value corresponding to any test area and the standard pixel value, it indicates that the structural parameters of the corresponding nanostructure unit are defective. Therefore, the length defect value of the corresponding lens nanostructure can be determined based on the comparison results between the pixel values ​​of each region and the standard pixel values. The calculation process of the corresponding length defect value can be specifically as follows:

[0046] in, is the length defect value, is the length defect coefficient, is the pixel difference, where the pixel difference can be obtained by summing up the absolute differences between the pixel value of each region and the standard pixel value, and the absolute difference can be understood as the absolute value of the difference; At the same time, the number of target pixels constituting the same test area, i.e., the target pixel number, is counted and obtained, and the target pixel number is compared with the preset standard pixel number of the corresponding test light. The width defect value of the lens nanostructure is evaluated and obtained according to the comparison result. Here, it can be explained that the standard pixel number can be understood as the number of pixels corresponding to the light area that can be formed on the test acquisition board based on the transmission of the test light on the nanostructure unit when the structural parameters of the corresponding nanostructure unit are correct. By comparing the target pixel number with the standard pixel number of the corresponding test light, it can be determined whether the area size of the test area corresponding to each nanostructure unit has defects. It can be understood that when the target pixel number is different from the standard pixel number, it indicates that the structural parameters of the nanostructure unit also have defects, which are specifically reflected in the corresponding structural width. It can be explained that the larger the structural width, the larger the corresponding light area formed on the test acquisition board, and the smaller the corresponding structural width, the smaller the corresponding light area formed on the test acquisition board should be. Therefore, the width defect value of the corresponding lens nanostructure can be determined based on the comparison result between the target pixel number and the standard pixel number, wherein the calculation process of the corresponding width defect value can be specifically as follows:

[0047] in, is the width defect value, is the width defect coefficient, is the quantity difference, where the quantity difference can be obtained by summing up the absolute differences between each target pixel quantity and the standard pixel quantity, and the absolute difference can be understood as the absolute value of the difference; Finally, after the length defect value and the width defect value are obtained, the two can be summed to obtain a comprehensive defect value of the corresponding lens nanostructure, and the comprehensive defect value is compared with a preset evaluation threshold; If the comprehensive defect value is greater than or equal to the preset evaluation threshold, the lens nanostructure is determined to be unqualified, which means that the lens nanostructure cannot be used normally and needs to be scrapped.

[0048] Furthermore, in order to enable the identification of each nanostructure unit having defects in the corresponding structural parameters, in this embodiment, it can be achieved based on the following steps: Establishing a test display model based on the test image, and obtaining a standard length and a standard width corresponding to the lens nano-unit; In response to any area pixel value being different from the standard pixel value, determining the lens nano-unit corresponding to the area pixel value as having a length abnormality attribute, and obtaining a pixel value ratio between the area pixel value and the standard pixel value; Adjusting the standard length based on the pixel value ratio to obtain an abnormal length corresponding to the lens nano-unit; Based on the abnormal length, generating a length abnormal nano-sub-model corresponding to the lens nano-unit in the test display model, and performing pixel rendering based on a preset first color on the length abnormal nano-sub-model; In response to any target pixel number being different from the standard pixel number, determining the lens nanometer unit corresponding to the pixel value of the area as a width abnormality attribute, and obtaining a pixel number ratio between the target pixel number and the standard pixel number; Adjusting the standard width based on the pixel number ratio to obtain an abnormal width corresponding to the lens nanometer unit; generating a width abnormal nano-sub-model corresponding to the lens nano-unit in the test display model based on the abnormal width, and performing pixel rendering based on a preset second color on the width abnormal nano-sub-model; In response to the completion of the generation of all length-abnormal nano-models and width-abnormal nano-models, normal nano-models corresponding to all other lens nano-units except the corresponding length-abnormal attributes and width-abnormal attributes are generated in the test display model based on the standard length and standard width, and pixel rendering based on a preset third color is performed on each normal nano-model.

[0049] For example, in this embodiment, the identification of nanostructure units with defective structural parameters can be achieved based on the following content: First, a test display model for displaying the state of the lens nano-unit can be constructed according to the test image, and the standard length and standard width of the lens nano-unit can be obtained. It should be noted that the standard length and standard width can be understood as the specific length and specific width of the lens nano-unit with no defects in the corresponding structural parameters; Next, if the pixel value of any area of ​​the corresponding test image does not match the preset standard pixel value, it is determined that the lens nano-unit corresponding to the pixel value of the area has an abnormal length attribute, and the ratio between the pixel value of the abnormal area and the standard pixel value can be further calculated. Based on the above pixel value ratio, the standard length of the lens nano-unit is adjusted accordingly to obtain the abnormal length of the lens nano-unit; Next, in the test display model, a length abnormal nano sub-model corresponding to the lens nano unit can be generated at a relative position corresponding to the lens nano unit according to the abnormal length, and pixel rendering is performed on the model using a preset first color; Then, each test area in the test image is traversed in the same manner. If the target pixel number of a test area is inconsistent with the preset standard pixel number, it is determined that the lens nanometer unit corresponding to the area has an abnormal width attribute, and the ratio between the target pixel number and the standard pixel number can be calculated. Based on the above pixel number ratio, the standard width of the lens nanometer unit is adjusted accordingly to obtain the abnormal width of the lens nanometer unit. Then, in the test display model, a width abnormal nano-sub-model corresponding to the lens nano-unit can be generated at a relative position corresponding to the lens nano-unit according to the abnormal length, and pixel rendering is performed on the model using a preset second color; Finally, after completing the generation of all length-abnormal nano-models and width-abnormal nano-models, for all other lens nano-units except those with length-abnormal properties or width-abnormal properties, their corresponding normal nano-models can be generated in the test display model according to the standard length and standard width obtained above, and the above normal nano-models can be pixel rendered using a preset third color.

[0050] It should be noted that, through the above method, abnormal detection and visual display of lens nano units are realized, which is convenient for quickly identifying and distinguishing the abnormal length and width of lens nano units, as well as the normal state; in addition, since the minimum size of the lens nano structure (structure length and width or structure gap) is smaller than the working wavelength of the metasurface, it has exceeded the diffraction limit. Therefore, in order to realize the detection of the processing quality of the lens nano structure based on the above method steps, it is necessary to ensure that the working wavelength of the above test light and the test acquisition board is smaller than the minimum size of the lens nano structure.

[0051] In summary, according to the scheme of this embodiment, this embodiment successfully prepares a fiber meta-lens with high-precision nanostructure by setting a lens substrate on a fiber optic ferrule fixing base and determining the white light emitting area on the lens substrate based on the white light optical path. This method ensures the precise alignment and efficient light transmission of the nanostructure through adaptive exposure technology, and significantly improves the coupling efficiency between the optical fiber and the lens. Specifically, the formation of the lens nanostructure is based on the adaptive exposure of the white light optical path, which avoids the light transmission loss caused by alignment errors in traditional processes and improves the performance of optical devices. In addition, the invention ensures the high precision and large-area uniformity of the nanostructure through processes such as spin coating, exposure, development, thin film deposition, and etching of photoresist, improves the preparation efficiency and consistency, and is suitable for the integrated application of high-precision optical devices and photonic chips.

[0052] Another embodiment of the present invention provides a fiber metalens manufactured based on the above-mentioned fiber metalens manufacturing method. Figure 2 As shown in the corresponding structural block diagram, the optical fiber meta-lens includes: Lens substrates and lens nanostructures; Wherein, the lens substrate is arranged on an optical fiber fixing base, and the lens nanostructure is arranged on a side of the lens substrate away from the optical fiber core fixing base.

[0053] For example, in this embodiment, in order to further illustrate the structure of the optical fiber meta-lens, this embodiment also shows a plurality of physical pictures, for example, Fig.15 A physical diagram of the optical fiber ferrule fixing base in this embodiment is shown; Fig.16 A physical diagram showing that the lens substrate and the optical fiber ferrule fixing base in this embodiment are integrally formed based on femtosecond laser bonding; Fig.17 An interface diagram of femtosecond laser bonding of a lens base and an optical fiber ferrule fixing base in this embodiment is shown; Fig.18 A physical diagram of the optical fiber ferrule fixed on the optical fiber ferrule fixing base in this embodiment is shown; Fig.19 The microscope result diagram showing the white light emitting area in this embodiment is formed on the side of the lens substrate away from the optical fiber ferrule fixing base and corresponding to the same area; Fig. 20 The microscope result image of the substrate step corresponding to the white light emitting area in the present embodiment is shown; Fig.21 The microscope result diagram showing the coincidence of the center of the substrate step and the center of the lens using the "parallel line tangent point centering method" in this embodiment is shown; Fig. 22 The SEM image of the corresponding lens nanostructure in this embodiment is shown.

[0054] In the description provided herein, algorithms and displays are not inherently related to any particular computer, virtual system or other device. Various general purpose systems can also be used together with the examples of the present invention. According to the above description, it is obvious that the structure required for constructing such systems. In addition, the present invention is not directed to any specific programming language either. It should be understood that various programming languages ​​can be utilized to implement the content of the present invention described herein, and the above description of specific languages ​​is for the purpose of disclosing the preferred embodiment of the present invention.

[0055] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0056] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof.

[0057] Those skilled in the art will appreciate that the modules or units or components of the devices in the examples disclosed herein may be arranged in the devices described in the embodiment, or alternatively may be located in one or more devices different from the devices in the examples. The modules in the foregoing examples may be combined into one module or may be divided into multiple submodules.

[0058] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and furthermore may be divided into a plurality of submodules or subunits or subcomponents.

[0059] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present invention and to form different embodiments.

[0060] In addition, some of the embodiments are described herein as methods or combinations of method elements that can be implemented by a processor of a computer system or by other devices that perform the functions. Therefore, a processor with necessary instructions for implementing the method or method elements forms a device for implementing the method or method elements. In addition, the elements described herein of the device embodiments are examples of devices for implementing the functions performed by the elements for the purpose of implementing the invention.

[0061] As used herein, unless otherwise specified, the use of ordinal numbers "first," "second," "third," etc. to describe common objects merely indicates that different instances of similar objects are involved, and is not intended to imply that the objects so described must have a given order in time, space, order, or in any other manner.

[0062] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is primarily selected for readability and instructional purposes, rather than for explaining or limiting the subject matter of the present invention.

Claims

1. A method for manufacturing a fiber meta-lens, characterized in that: include: A lens substrate is arranged on a fiber optic ferrule fixing base, wherein the fiber optic ferrule fixing base is provided with a fiber optic ferrule limiting hole, and the fiber optic ferrule limiting hole accommodates the fiber optic ferrule, wherein the fiber optic ferrule has a fiber optic transmission channel; irradiating the optical fiber transmission channel with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and determining a white light emitting area from the lens substrate based on the white light path; Based on the white light emitting area, a lens nanostructure corresponding to the same area is formed on a side of the lens substrate away from the optical fiber ferrule fixing base.

2. The method for manufacturing a fiber metalens according to claim 1, characterized in that: The optical fiber transmission channel is irradiated with white light along the extension direction of the optical fiber transmission channel to form a white light path propagating in the optical fiber transmission channel, and a white light emission area emitted from the lens substrate is determined based on the white light path, including: Spin coating photoresist on the side of the lens substrate away from the optical fiber ferrule fixing base, and curing the obtained photoresist layer; The optical fiber transmission channel is irradiated with white light along the extension direction of the optical fiber transmission channel to form a white light path that propagates in the optical fiber transmission channel, and the photoresist layer is exposed and developed based on the white light path to form a substrate shielding portion corresponding to the white light emitting area on the lens substrate.

3. The method for manufacturing a fiber metalens according to claim 2, characterized in that: Spin coating photoresist on a side of the lens substrate away from the optical fiber ferrule fixing base, and curing the obtained photoresist layer, comprising: Performing a first spin coating operation based on photoresist at a preset first spin coating speed for a preset first spin coating time on a side of the lens substrate away from the optical fiber ferrule fixing base; After the first spin coating operation is completed, a second spin coating operation based on photoresist is performed on a side of the lens substrate away from the optical fiber ferrule fixing base at a preset second spin coating speed for a preset second spin coating time; Performing a pre-baking treatment on the photoresist layer obtained based on the first spin coating operation and the second spin coating operation at a preset first baking temperature for a preset first baking time; After the pre-baking treatment is completed, the photoresist layer is subjected to a mid-baking treatment at a preset second baking temperature for a preset second baking time; After the intermediate baking process is completed, the photoresist layer is subjected to a post-baking process at a preset third baking temperature for a preset third baking time to complete the curing of the photoresist layer.

4. The method for manufacturing a fiber metalens according to claim 2, characterized in that: Based on the white light emitting area, a lens nanostructure corresponding to the same area is formed on a side of the lens substrate away from the optical fiber ferrule fixing base, including: Based on the base shielding portion, the lens base is away from the side of the optical fiber ferrule fixing base. Etching the remaining area except the white light emitting area to reduce the thickness of the remaining area, thereby forming a substrate step located on the lens substrate and corresponding to the same area as the white light emitting area; Depositing an a-Si:H thin film on the side of the lens substrate away from the optical fiber ferrule fixing base to obtain an a-Si:H thin film layer; The a-Si:H thin film layer is imaged to obtain a lens nanostructure.

5. The method for manufacturing a fiber metalens according to claim 4, characterized in that: The method of obtaining the a-Si:H thin film layer further comprises: A Cartesian coordinate system is established based on the a-Si:H thin film layer, a tangent line 1 having a tangent relationship with the contour of the a-Si:H thin film layer is established, and a tangent point A corresponding to the tangent line 1 is obtained; Establishing a tangent line 2 which is parallel to the tangent line 1 and has a tangent relationship with the profile of the a-Si:H thin film layer, and obtaining a tangent point B corresponding to the tangent line 2, wherein the tangent line 1 and the tangent line 2 do not overlap; The first point coordinates and the second point coordinates corresponding to the tangent point A and the tangent point B are determined based on the Cartesian coordinate system, and the center coordinate point of the corresponding a-Si:H thin film layer is determined based on the first point coordinates and the second point coordinates.

6. The method for manufacturing a fiber metalens according to claim 4, characterized in that: The a-Si:H thin film layer is imaged to obtain a lens nanostructure, including: Spin coating electron beam glue on the side of the a-Si:H thin film layer away from the lens substrate, and patterning the obtained electron beam glue layer to obtain a sub-wavelength nanostructure corresponding to the white light emitting area and a thin film shielding portion corresponding to the remaining area; Performing Cr-based thin film deposition on a side of the lens substrate away from the optical fiber ferrule fixing base to obtain a Cr thin film layer; The Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure are peeled off to obtain a Cr nanostructure corresponding to the white light emitting area; Etching the a-Si:H thin film layer to obtain a composite nanostructure corresponding to the white light emitting area, wherein the composite nanostructure includes an a-Si:H nanostructure located on the substrate step and a Cr nanostructure located on the a-Si:H nanostructure; The Cr nanostructure is removed to obtain a lens nanostructure consisting of the substrate step and the a-Si:H nanostructure.

7. According to the claim 6 The method for manufacturing the optical fiber meta-lens is characterized in that: The Cr thin film layer, the electron beam gel layer, and the sub-wavelength nanostructure are peeled off, including: The lens substrate is placed in an acetone solution corresponding to a preset solution temperature, and the Cr film layer, the electron beam gel layer, and the sub-wavelength nanostructure on the lens substrate are peeled off based on ultrasound.

8. The method for manufacturing a fiber metalens according to claim 6, characterized in that: Removing the Cr nanostructure comprises: The Cr nanostructure is rinsed with an etching solution formed by mixing ammonium cerium nitrate, glacial acetic acid and deionized water.

9. The method for manufacturing a fiber metalens according to claim 6, characterized in that: The a-Si:H thin film layer is etched to obtain a composite nanostructure corresponding to the white light emitting region, including: The a-Si:H thin film layer is subjected to gas etching using SF6 etching gas to obtain a composite nanostructure corresponding to the white light emitting region.

10. A fiber metalens manufactured by the method for manufacturing a fiber metalens according to any one of claims 1 to 9, characterized in that: include: Lens substrates and lens nanostructures; Wherein, the lens substrate is arranged on an optical fiber fixing base, and the lens nanostructure is arranged on a side of the lens substrate away from the optical fiber core fixing base.

Images