Preparation method of double-sided metasurface component and double-sided metasurface component

Abstract

The invention provides a preparation method of a double-sided metasurface component and the double-sided metasurface component. The preparation method comprises the following steps: forming a first metasurface structure on a first silicon substrate; forming a second metasurface structure on the first surface of the glass substrate; bonding the first metasurface structure to a second surface, opposite to the first surface, of the glass substrate through a bonding process, so that the first metasurface structure is aligned with the second metasurface structure; after bonding, removing the first silicon substrate to obtain the double-sided super-surface component; high-precision alignment between the first metasurface structure and the second metasurface structure can be directly realized through the alignment mechanism on the bonding equipment, and the optical performance of a final product is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of super surface materials, and in particular to a preparation method of a double-sided super surface component and a double-sided super surface component. Background Art

[0002] Metasurface components are formed by forming subwavelength structures on a plane. Metasurface components have special electromagnetic properties and excellent interface control capabilities. The subwavelength structure design can locally change the amplitude, polarization and phase of the incident light. In addition, metasurface components are small in size and light in weight, which facilitates the realization of compact optical structures. Therefore, the use of metasurface components to prepare optical components has attracted much attention in recent years.

[0003] Metasurface components include single-sided metasurface components and double-sided metasurface components, wherein a single-sided metasurface component refers to a metasurface structure formed only on one side of a substrate, and a double-sided metasurface component refers to a metasurface structure formed on both opposite sides of a substrate. Single-sided metasurface components have aberrations at oblique incidence, which makes them unable to meet the requirements of wide-angle imaging. However, double-sided metasurface components can well overcome the aberration problem of single-sided metasurface components at oblique incidence and can achieve wide-angle imaging. Therefore, double-sided metasurface components have received more and more attention.

[0004] The current effective preparation process for the double-sided metasurface component is to use a photolithography machine to make a layer of overlay marks on the back of the substrate, and then use the photolithography machine to make the metasurface pattern on the back of the substrate, but conventional photolithography machines cannot achieve overlay alignment on both sides; or use the wafer notch as a reference for overlay on the front and back sides, but due to the limitation of the accuracy of the wafer notch, the alignment will be relatively poor. Therefore, it is impossible to achieve high-precision alignment of the metasurface structures on both sides of the double-sided metasurface component, affecting the optical performance of the final double-sided metasurface component. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a high-precision aligned double-sided super-surface component and a double-sided super-surface component.

[0006] To achieve the above-mentioned purpose, the present invention adopts the following technical solution: A method for preparing a double-sided super-surface component comprises the following steps:

[0007] forming a first supersurface structure on a first silicon substrate;

[0008] Forming a second supersurface structure on the first surface of the glass substrate;

[0009] Bonding the first supersurface structure to a second surface of the glass substrate opposite to the first surface through a bonding process, so that the first supersurface structure is aligned with the second supersurface structure;

[0010] After bonding, the first silicon substrate is removed to obtain the double-sided metasurface component.

[0011] As a further improved technical solution of the present invention, “forming a second supersurface structure on the first surface of the glass substrate” specifically includes the following steps:

[0012] forming a second nanorod structure on the first surface of the glass substrate;

[0013] A protective material is filled in the gaps of the second nanorod structures to form a second protective layer.

[0014] As a further improved technical solution of the present invention, “forming a second supersurface structure on the first surface of the glass substrate” specifically includes the following steps:

[0015] forming a second super surface structure on a second silicon substrate;

[0016] The second metasurface structure is bonded to the first surface of the glass substrate through a bonding process.

[0017] As a further improved technical solution of the present invention, after the second supersurface structure is bonded to the first surface of the glass substrate and before the first supersurface structure is bonded to the second surface of the glass substrate opposite to the first surface through a bonding process; or, after the second supersurface structure is bonded to the first surface of the glass substrate through a bonding process and the first supersurface structure is bonded to the second surface of the glass substrate opposite to the first surface through a bonding process, the preparation method also includes the following step: removing the second silicon substrate.

[0018] As a further improved technical solution of the present invention, “forming a second super-surface structure on a second silicon substrate” specifically comprises the following steps:

[0019] Depositing a protective material on a surface of the second silicon substrate to form a second protective film;

[0020] forming a second nanorod structure on the second protective film;

[0021] Filling a protective material in the gaps of the second nanorod structures to form a second protective layer;

[0022] Polishing is performed to make the surface of the second protective layer flat.

[0023] As a further improved technical solution of the present invention, “forming a first supersurface structure on a first silicon substrate” specifically includes the following steps:

[0024] Depositing a protective material on a surface of the first silicon substrate to form a first protective film;

[0025] forming a first nanocolumn structure on the first protective film;

[0026] Filling a protective material in the gaps of the first nanorod structures to form a first protective layer;

[0027] Polishing is performed to make the surface of the first protective layer flat.

[0028] As a further improved technical solution of the present invention, the protective material is SiO2 or Al2O3 or SiN x .

[0029] As a further improved technical solution of the present invention, the bonding process comprises the following steps:

[0030] The glass substrate is aligned and bonded with the super surface structure to be bonded, and then an annealing treatment is performed to bond the glass substrate with the super surface structure to be bonded.

[0031] As a further improved technical solution of the present invention, the process parameters of the annealing treatment are: a heating rate of less than 15°C / min, a target temperature of 100°C to 1000°C, and an annealing time of 1h to 5h.

[0032] In order to achieve the above-mentioned purpose of the invention, the present invention also provides a double-sided super-surface component, which is prepared by the above-mentioned preparation method of the double-sided super-surface component.

[0033] The beneficial effects of the present invention are as follows: in the preparation method of the double-sided supersurface component of the present invention, on the basis of forming a second supersurface structure on the first surface of the glass substrate, the first supersurface structure is bonded to the second surface of the glass substrate opposite to the first surface through a bonding process, and high-precision alignment between the first supersurface structure and the second supersurface structure can be directly achieved through the alignment mechanism on the bonding device. The alignment accuracy between the first supersurface structure and the second supersurface structure can reach 50nm or even higher, which greatly improves the optical performance of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a method for preparing a double-sided super-surface component in the first embodiment of the present invention;

[0035] Figure 2 This is a method for preparing a double-sided super-surface component in the second embodiment of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be described in detail below in conjunction with the various embodiments shown in the accompanying drawings. Figure 1 to Figure 2 It is shown as a preferred embodiment of the present invention. However, it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformation or replacement of functions, methods, or structures made by ordinary technicians in the field according to these embodiments shall fall within the protection scope of the present invention.

[0037] Furthermore, it should be understood that although the terms first, second, etc. may be used in this document to describe various elements or structures, these described objects should not be limited by the above terms. The above terms are only used to distinguish these described objects from each other.

[0038] Please refer to Figure 1 As shown, a method for preparing a double-sided super-surface component 10 in a first embodiment of the present invention is shown, and the preparation method comprises the following steps:

[0039] S1, forming a first supersurface structure 2 on a first silicon substrate 1;

[0040] S2, forming a second supersurface structure 4 on the first surface of the glass substrate 3;

[0041] S3, bonding the first supersurface structure 2 to the second surface of the glass substrate 3 opposite to the first surface through a bonding process, so that the first supersurface structure 2 is aligned with the second supersurface structure 4;

[0042] S4. After bonding, the first silicon substrate 1 is removed to obtain the double-sided metasurface component 10.

[0043] It should be noted that the above-mentioned numbers S1, S2, S3, S4 and the numbers used below are all numbers made for the convenience of description and do not limit the order of the steps. For example, steps S1 and S2 can be performed first S1 and then S2, or first S2 and then S1, or steps S1 and S2 can be performed simultaneously.

[0044] In the present invention, on the basis of forming the second supersurface structure 4 on the first surface of the glass substrate 3, the first supersurface structure 2 is bonded to the second surface of the glass substrate 3 opposite to the first surface through a bonding process, and high-precision alignment between the first supersurface structure 2 and the second supersurface structure 4 can be directly achieved through the alignment mechanism on the bonding device, so that the alignment accuracy between the first supersurface structure 2 and the second supersurface structure 4 can reach 50nm or even higher, which greatly improves the optical performance of the final product. At the same time, the preparation process of the double-sided supersurface component 10 is simplified.

[0045] In addition, in the present invention, for the first supersurface structure 2, the first silicon substrate 1 is directly used to manufacture the supersurface structure, and the preparation of the supersurface structure using the silicon substrate is a mature process, which is easier to produce and can reduce costs.

[0046] Furthermore, step S1 is specifically as follows:

[0047] S11, depositing a protective material on a surface of the first silicon substrate 1 to form a first protective film 21;

[0048] S12, forming a first nanorod structure 22 on the first protective film 21;

[0049] S13, filling the gaps of the first nanorod structures 22 with a protective material to form a first protective layer 23;

[0050] Polishing is performed to make the surface of the first protective layer 23 flat.

[0051] The forming process of the first nanorod structure 22 in step S12, the filling process of the protective material in step S13 and the final polishing process can all use the forming process of the super surface structure in the prior art, and will not be described in detail here.

[0052] Specifically, in step S11, a protective material can be deposited on one surface of the first silicon substrate 1 by PVD or CVD to form a protective film. The protective film can serve as an etching stopper for the subsequent formation of the first nanocolumn structure 22; at the same time, when the first silicon substrate 1 is removed in the subsequent step S4, the protective film can also protect the first nanocolumn structure 22; and in the final double-sided metasurface component 10 product, the protective film can also serve as an anti-reflection film layer to further improve the optical performance of the final product.

[0053] Furthermore, “polishing to make the surface of the first protective layer 23 flat” means that the flatness and smoothness of the side of the first protective layer 23 away from the first silicon substrate 1 meet the preset requirements, so as to facilitate the subsequent bonding of the side of the first supersurface structure 2 away from the first silicon substrate 1 with the second surface of the glass substrate 3.

[0054] Specifically, the side of the first protective layer 23 away from the first silicon substrate 1 satisfies Ra<1nm, TTV<5um, and correspondingly, the second surface of the glass substrate 3 also needs to satisfy Ra<1nm, TTV<5um, so that the side of the first protective layer 23 away from the first silicon substrate 1 and the second surface of the glass substrate 3 both achieve a high degree of flatness and smoothness, so as to facilitate the subsequent bonding of the first supersurface structure 2 to the second surface of the glass substrate 3.

[0055] It is known that the second surface of the glass substrate 3 can meet the above-mentioned flatness and smoothness requirements through the processing technology of the glass itself (such as polishing technology).

[0056] In a specific embodiment, the protective material is SiO2. Of course, this is not limited to this. In other embodiments, the protective material can also be Al2O3 or SiN x .

[0057] In this embodiment, combined with Figure 1 As shown, step S2 specifically includes the following steps:

[0058] S21, forming a second nanorod structure 41 on the first surface of the glass substrate 3;

[0059] S22 , filling the gaps of the second nanorod structures 41 with a protective material to form a second protective layer 42 .

[0060] The forming process of the second nanorod structure 41 in step S21 and the filling process of the protective material in step S22 can both use the forming process of the super surface structure in the prior art, and will not be described in detail here.

[0061] In a specific embodiment, the protective material is SiO 2. Of course, it is not limited to this. In other embodiments, the protective material can also be Al 2 O 3 or SiN x.

[0062] Further, after step S22, step S2 further includes the following steps:

[0063] Polishing can make the surface of the second protective layer 42 flat, thereby improving the optical performance of the final product.

[0064] Specifically, the material of the glass substrate 3 can be selected from common glass, such as soda-lime glass, borosilicate glass, quartz glass, etc., and can be selected according to the requirements of the final product to improve the flexibility of the final product and reduce the cost.

[0065] Furthermore, the thickness of the glass substrate 3 is 210 um to 2000 um. It is known that the thickness of the glass substrate 3 can also be selected according to the requirements of the final product.

[0066] Furthermore, the bonding process in step S3 includes the following steps:

[0067] The second surface of the glass substrate 3 and the first supersurface structure 2 are first aligned and bonded, and then an annealing treatment is performed to bond the second surface of the glass substrate 3 and the first supersurface structure 2 .

[0068] After the second surface of the glass substrate 3 and the first supersurface structure 2 are aligned and bonded, the first supersurface structure 2 and the second supersurface structure 4 are aligned with high precision. At this time, van der Waals force is formed between the second surface of the glass substrate 3 and the first supersurface structure 2, so that the second surface of the glass substrate 3 and the first supersurface structure 2 are adsorbed and bonded together. The subsequent annealing treatment can increase the bonding force between the second surface and the first supersurface structure 2, eliminate the air in the bonding gap, and achieve the bonding between the first supersurface structure 2 and the glass substrate 3.

[0069] Specifically, the process parameters of the annealing treatment are: a heating rate of less than 15°C / min, a target temperature of 100°C to 1000°C, and an annealing time of 1h to 5h. During the annealing treatment, slowly heating up the temperature is more conducive to the discharge of air in the bonding gap, thereby improving the bonding performance between the first metasurface structure 2 and the glass substrate 3.

[0070] It is known that the specific target temperature and annealing time can be selected according to the heat resistance of the material of the glass substrate 3, silicon substrate, etc.

[0071] Furthermore, step S4 is specifically as follows: after the first supersurface structure 2 is bonded to the glass substrate 3, the first silicon substrate 1 can be removed by wet etching to transfer the first supersurface structure 2 to the glass substrate 3, or the thickness of the first silicon substrate 1 can be thinned to a few microns or more than ten microns by a conventional thinning process, and then the remaining first silicon substrate 1 can be removed by dry etching or wet etching to transfer the first supersurface structure 2 to the glass substrate 3.

[0072] Specifically, process parameters of wet etching, thinning process, dry etching, etc. can be set according to specific needs, and will not be described in detail here.

[0073] Please combine Figure 2 As shown, it is a method for preparing a double-sided super-surface component 10' in the second embodiment of the present invention. The difference between the method for preparing a double-sided super-surface component 10' in the second embodiment of the present invention and the method for preparing a double-sided super-surface component 10 in the first embodiment is that step S2' in this embodiment is specifically:

[0074] S21', forming a second super surface structure 4' on the second silicon substrate 5;

[0075] S22', bonding the second metasurface structure 4' to the first surface of the glass substrate 3 through a bonding process.

[0076] In this embodiment, the first supersurface structure 2 and the second supersurface structure 4' are both made of silicon substrates. The preparation of supersurface structures using silicon substrates is a mature process, which is easier to produce, can reduce costs and improve yields.

[0077] Specifically, step S21' includes the following steps:

[0078] S211, depositing a protective material on a surface of the second silicon substrate 5 to form a second protective film 43;

[0079] S212, forming a second nanorod structure 41 on the second protective film 43;

[0080] S213, filling the gaps of the second nanorod structures 41 with a protective material to form a second protective layer 42;

[0081] Polishing is performed to make the surface of the second protection layer 42 flat.

[0082] Among them, the forming process of the second nanorod structure in step S212, the filling process of the protective material in step S213 and the final polishing process can all use the forming process of the super surface structure in the prior art, and will not be repeated here.

[0083] Specifically, in step S211, a protective material can be deposited on one surface of the second silicon substrate 5 by PVD or CVD to form a protective film. The protective film can serve as an etching stopper for the subsequent formation of the second nanorod structure 41; at the same time, when the second silicon substrate 5 is removed later, the protective film can also protect the second nanorod structure 41; and in the final double-sided metasurface component 10' product, the second protective film 43 can also serve as an anti-reflection film layer to further improve the optical performance of the final product.

[0084] Furthermore, “polishing to make the surface of the second protective layer 42 flat” means that the flatness and smoothness of the side of the second protective layer 42 away from the second silicon substrate 5 meet the preset requirements, so as to facilitate the subsequent bonding of the side of the second supersurface structure 4' away from the second silicon substrate 5 with the first surface of the glass substrate 3.

[0085] Specifically, the side of the second protective layer 42 away from the second silicon substrate 5 satisfies Ra<1nm, TTV<5um, and correspondingly, the first surface of the glass substrate 3 also needs to satisfy Ra<1nm, TTV<5um, so that the side of the second protective layer 42 away from the second silicon substrate 5 and the first surface of the glass substrate 3 both achieve high flatness and smoothness, so as to facilitate the subsequent bonding of the side of the second supersurface structure 4' away from the second silicon substrate 5 with the first surface of the glass substrate 3.

[0086] It is known that the first surface of the glass substrate 3 can meet the above-mentioned flatness and smoothness requirements through the processing technology of the glass itself (such as polishing technology).

[0087] In a specific embodiment, the protective material is SiO2. Of course, this is not limited to this. In other embodiments, the protective material can also be Al2O3 or SiN x .

[0088] Furthermore, the bonding process in step S22' includes the following steps:

[0089] The first surface of the glass substrate 3 and the second supersurface structure 4 ′ are first aligned and bonded, and then an annealing treatment is performed to bond the first surface of the glass substrate 3 and the second supersurface structure 4 ′.

[0090] After the first surface of the glass substrate 3 and the second supersurface structure 4' are aligned and bonded, a van der Waals force is formed between the first surface of the glass substrate 3 and the second supersurface structure 4', so that the first surface of the glass substrate 3 and the second supersurface structure 4' are adsorbed and bonded together. The bonding force between the first surface and the second supersurface structure 4' can be increased by annealing treatment, and the air in the bonding gap can be eliminated, so as to achieve bonding between the second supersurface structure 4' and the glass substrate 3.

[0091] Specifically, the process parameters of the annealing treatment are: a heating rate of less than 15°C / min, a target temperature of 100°C to 1000°C, and an annealing time of 1h to 5h. During the annealing treatment, slowly heating up the temperature is more conducive to the discharge of air in the bonding gap, thereby improving the bonding performance between the second metasurface structure 4' and the glass substrate 3.

[0092] It is known that the specific target temperature and annealing time can be selected according to the heat resistance of the materials of the glass substrate 3 , the second silicon substrate 5 , etc.

[0093] Furthermore, in a specific embodiment, after the second supersurface structure 4' is bonded to the first surface of the glass substrate 3 by a bonding process, and before the first supersurface structure 2 is bonded to the second surface of the glass substrate 3 opposite to the first surface by a bonding process, the preparation method also includes S23', removing the second silicon substrate 5; at this time, the second silicon substrate 5 can be removed by wet etching to transfer the second supersurface structure 4' to the glass substrate 3, or the thickness of the second silicon substrate 5 can be first thinned to several microns or more than ten microns by a conventional thinning process, and then the remaining second silicon substrate 5 is removed by dry etching or wet etching to transfer the second supersurface structure 4' to the glass substrate 3. Of course, this is not limited to this. In other embodiments, after the second supersurface structure 4' is bonded to the first surface of the glass substrate 3 and the first supersurface structure 2 is bonded to the second surface of the glass substrate 3, the second silicon substrate 5 and the first silicon substrate 1 can be removed. At this time, the second silicon substrate 5 and the first silicon substrate 1 can be removed simultaneously by wet etching to transfer the second supersurface structure 4' and the first supersurface structure 2 to the glass substrate 3 simultaneously. Alternatively, one side (the second silicon substrate 5 or the first silicon substrate 1) can be thinned by a conventional thinning process, and then the other side (the first silicon substrate 1 or the second silicon substrate 5) can be thinned. Finally, the remaining first silicon substrate 1 and the second silicon substrate 5 can be removed by dry etching or wet etching to transfer the second supersurface structure 4' and the first supersurface structure 2 to the glass substrate 3 simultaneously.

[0094] The method for preparing the double-sided super-surface component 10 ′ in the second embodiment of the present invention is the same as the method for preparing the double-sided super-surface component 10 in the first embodiment except for the above-mentioned differences, and will not be described in detail here.

[0095] Furthermore, the present invention also provides a double-sided super-surface component 10, 10' prepared by the preparation method of the double-sided super-surface component 10, 10'. The preparation method of the double-sided super-surface component 10, 10' can adopt the preparation method of the double-sided super-surface component 10 in the first embodiment described above, and can also adopt the preparation method of the double-sided super-surface component 10' in the second embodiment described above, and no further description is given here.

[0096] Compared with the prior art, in the preparation method of the double-sided supersurface component 10 in the present invention, on the basis of forming the second supersurface structure 4 on the first surface of the glass substrate 3, the first supersurface structure 2 is bonded to the second surface of the glass substrate 3 opposite to the first surface through a bonding process, and high-precision alignment between the first supersurface structure 2 and the second supersurface structure 4 can be directly achieved through the alignment mechanism on the bonding device. The alignment accuracy between the first supersurface structure 2 and the second supersurface structure 4 can reach 50nm or even higher, which greatly improves the optical performance of the final product.

[0097] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0098] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a double-sided super-surface component, characterized in that: The steps include: forming a first supersurface structure on a first silicon substrate; Forming a second supersurface structure on the first surface of the glass substrate; Bonding the first supersurface structure to a second surface of the glass substrate opposite to the first surface through a bonding process, so that the first supersurface structure is aligned with the second supersurface structure; After bonding, the first silicon substrate is removed to obtain the double-sided metasurface component.

2. The method for preparing a double-sided super-surface component according to claim 1, characterized in that: “Forming a second super-surface structure on the first surface of the glass substrate” specifically includes the following steps: forming a second nanorod structure on the first surface of the glass substrate; A protective material is filled in the gaps of the second nanorod structures to form a second protective layer.

3. The method for preparing a double-sided super-surface component according to claim 1, characterized in that: “Forming a second super-surface structure on the first surface of the glass substrate” specifically includes the following steps: forming a second super surface structure on a second silicon substrate; The second metasurface structure is bonded to the first surface of the glass substrate through a bonding process.

4. The method for preparing a double-sided super-surface component according to claim 3, characterized in that: After bonding the second supersurface structure to the first surface of the glass substrate and before bonding the first supersurface structure to the second surface of the glass substrate opposite to the first surface through a bonding process; or, after bonding the second supersurface structure to the first surface of the glass substrate through a bonding process and bonding the first supersurface structure to the second surface of the glass substrate opposite to the first surface through a bonding process, the preparation method further includes the following step: removing the second silicon substrate.

5. The method for preparing a double-sided super-surface component according to claim 3, characterized in that: “Forming a second super surface structure on a second silicon substrate” specifically includes the following steps: Depositing a protective material on a surface of the second silicon substrate to form a second protective film; forming a second nanorod structure on the second protective film; Filling a protective material in the gaps of the second nanorod structures to form a second protective layer; Polishing is performed to make the surface of the second protective layer flat.

6. The method for preparing a double-sided super-surface component according to claim 1, characterized in that: “Forming a first supersurface structure on a first silicon substrate” specifically includes the following steps: Depositing a protective material on a surface of the first silicon substrate to form a first protective film; forming a first nanocolumn structure on the first protective film; Filling a protective material in the gaps of the first nanorod structures to form a first protective layer; Polishing is performed to make the surface of the first protective layer flat.

7. The method for preparing a double-sided super-surface component according to claim 2, 5 or 6, characterized in that: The protective material is SiO2 or Al2O3 or SiN x .

8. The method for preparing a double-sided super-surface component according to claim 1 or 3, characterized in that: The bonding process comprises the following steps: The glass substrate is aligned and bonded with the super surface structure to be bonded, and then an annealing treatment is performed to bond the glass substrate with the super surface structure to be bonded.

9. The method for preparing a double-sided super-surface component according to claim 8, characterized in that: The process parameters of the annealing treatment are: a heating rate of less than 15°C / min, a target temperature of 100°C to 1000°C, and an annealing time of 1h to 5h.

10. A double-sided metasurface component, characterized in that: The double-sided super-surface component is prepared by the preparation method of the double-sided super-surface component described in any one of claims 1 to 9.

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