Plasmon metasurface sensor based on aluminum-titanium nitride alternating multi-nanometer lamination

Abstract

A plasmon metasurface sensor based on an aluminum-titanium nitride alternating multi-nanometer lamination relates to the technical field of plasmon metasurfaces and comprises a substrate layer, a plurality of layers of aluminum films and a plurality of layers of titanium nitride films. The aluminum films and the titanium nitride films are alternately arranged from bottom to top and are sequentially compounded on the substrate layer; a periodic nanopore array is formed in the substrate layer; and the number of layers of the aluminum films is consistent with that of the titanium nitride films. Through the aluminum-titanium nitride alternate multi-nano laminated structure design, the optical near field and sensing regulation range in biomolecule detection in a plasmon mode is expanded, the interaction range between light and substances is increased, the substance sensing performance is effectively improved, the biological detection accuracy is improved, and the wide multi-marker detection requirement is met; through the aluminum-titanium nitride alternating multi-nano laminated structure design, the strong dependence of a traditional plasmon sensing material on precious metal is eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of plasmonic metasurfaces, and particularly to a plasmonic metasurface sensor based on an alternating multi-nanometer stack of aluminum-titanium nitride. Background Art

[0002] In recent years, nano plasmonic metasurfaces have shown great application potential in many fields. Especially in the fields of biomedicine, environmental protection, chemical analysis, and disease monitoring, they play a key role as biosensing chips. It can achieve highly sensitive component detection. By capturing changes in optical signals, it can accurately detect the tiny changes generated when the surface binds to biomolecules. This detection method has significant advantages such as label-free, high sensitivity, fast response, and miniaturization, which greatly promotes the technological development and innovation in related fields.

[0003] In the selection of plasmonic metasurface materials, traditional noble metal materials such as gold and silver are widely used due to their good plasmonic properties. However, the high cost of these noble metals limits large-scale applications. At the same time, low-cost materials such as aluminum (Al) and titanium nitride (TiN) have gradually come into the research spotlight. Aluminum exhibits excellent plasmonic properties in the ultraviolet to visible light range and has great application potential in the field of optical sensing; titanium nitride, with its high chemical stability and excellent biocompatibility, is widely used as an anti-oxidation coating in the mechanical industry, which can significantly improve the wear resistance of metals and extend their service life. Previously, some researchers have explored the aluminum-titanium nitride stack structure and found that this structure can effectively solve the problem of easy oxidation of aluminum in the biological environment, bringing a new solution to the field of biosensing. However, the thickness of the titanium nitride layer in this structure is relatively thin, resulting in limited improvement in the anti-oxidation function, and the entire structure has only two thickness degrees of freedom of aluminum and titanium nitride, making it difficult to achieve extensive optical near-field regulation, limiting the sensing regulation range, and difficult to meet the needs of extensive multi-marker detection, thus restricting its performance in practical applications. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems in the prior art, such as low coupling efficiency, low near-field enhancement efficiency, and relatively high cost of plasmonic materials, and to provide a plasmonic metasurface sensor based on an alternating multi-nanometer stack of aluminum-titanium nitride. Through the design of the alternating multi-nanometer stack structure of aluminum-titanium nitride, the optical near-field and sensing regulation range in the detection of biomolecules in the plasmonic mode are expanded, the interaction range between light and matter is increased, the sensing performance of substances is effectively improved, the accuracy of biological detection is improved, and the needs of extensive multi-marker detection are met; through the design of the alternating multi-nanometer stack structure of aluminum-titanium nitride, the strong dependence on noble metals of traditional plasmonic sensing materials is eliminated.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A plasmonic metasurface sensor based on an alternating multi-nanometer stack of aluminum and titanium nitride includes a substrate layer, multiple aluminum thin films, and multiple titanium nitride films; the aluminum thin films and the titanium nitride films are alternately arranged from bottom to top and are sequentially compounded on the substrate layer; a periodic nanohole array is formed in the substrate layer; the number of layers of the aluminum thin films and the titanium nitride films is the same.

[0007] The number of layers of the aluminum thin films and the titanium nitride films is 2 to 4 layers.

[0008] The thickness of the aluminum thin film is 10 to 50 nm.

[0009] The thickness of the titanium nitride film is 5 to 8 nm.

[0010] The diameter of the nanohole is 200 to 300 nm.

[0011] The depth of the nanohole is 200 to 300 nm.

[0012] The material of the substrate layer is a silicon substrate.

[0013] The size of the plasmonic metasurface sensor based on the alternating multi-nanometer stack of aluminum and titanium nitride is 10 mm × 10 mm to 50 mm × 50 mm.

[0014] For the plasmonic metasurface sensor based on the alternating multi-nanometer stack of aluminum and titanium nitride provided by the present invention, its preparation method adopts mature technologies such as nickel imprinting, deep silicon etching, electron beam evaporation, and magnetron sputtering.

[0015] Compared with the prior art, the beneficial effects achieved by the technical solution of the present invention are:

[0016] The plasmonic metasurface sensor based on the alternating multi-nanometer stack of aluminum and titanium nitride provided by the present invention avoids the defects that the coupling efficiency between the incident light and the plasmon mode is low, which affects the near-field enhancement efficiency, and the interference between multiple modes weakens the local hot spots, thereby reducing the coupling efficiency. Through the design of the alternating multi-nanometer stack structure of aluminum and titanium nitride, the optical near-field and sensing regulation range in the detection of biomolecules in the plasmon mode are expanded, the interaction range between light and matter is increased, the sensing performance of substances is effectively improved, the accuracy of biological detection is improved, the demand for extensive multi-marker detection is met, and the limitation of the oxidation characteristics of the aluminum surface on the biomolecular sensing performance is overcome, effectively avoiding the serious dependence on precious metals of traditional plasmonic sensing materials. Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of the plasmonic metasurface sensor based on the alternating multi-nanometer stack of aluminum and titanium nitride described in Embodiment 1;

[0018] Figure 2 Schematic cross-sectional view of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 1;

[0019] Figure 3 Reflectivity spectrum diagram of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 1;

[0020] Figure 4 Normalized transverse electric field intensity distribution diagrams of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 1 at resonance valleys located at 232 nm, 360 nm, and 447 nm respectively;

[0021] Figure 5 Reflectivity spectrum diagram of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 2;

[0022] Figure 6 Normalized transverse electric field intensity distribution diagrams of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 2 at resonance valleys located at 229 nm, 357 nm, and 446 nm respectively;

[0023] Figure 7 Reflectivity spectrum diagram of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 3;

[0024] Figure 8 Normalized transverse electric field intensity distribution diagrams of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 3 at resonance valleys located at 227 nm, 352 nm, and 443 nm respectively;

[0025] Figure 9 Reflectivity spectrum diagram of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 4;

[0026] Figure 10 Normalized transverse electric field intensity distribution diagrams of the plasmonic metasurface sensor based on alternating aluminum-titanium nitride multi-nanometer stacks described in Example 4 at resonance valleys located at 276 nm, 431 nm, and 545 nm respectively. Detailed implementation manners

[0027] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] Example 1

[0029] Refer toFigure 1 and Figure 2 As shown in Figure 2 , this embodiment discloses a plasmonic metasurface sensor based on an alternating multi-nanometer stack of aluminum-titanium nitride, with a size of 40 mm × 40 mm, including a substrate layer, multiple aluminum thin films, and multiple titanium nitride films; the aluminum thin films and titanium nitride films are alternately arranged from bottom to top and are sequentially compounded on the substrate layer; a periodic nanohole array is formed on the substrate layer.

[0030] In this embodiment, the substrate layer uses a silicon substrate.

[0031] For the periodic nanohole array, the shape of the nanohole is a cylindrical structure, the diameter r of the nanohole is 200 nm, and the depth h2 of the nanohole is 200 nm.

[0032] The thickness h3 of the aluminum thin film is 50 nm, the thickness h4 of the titanium nitride film is 5 nm, and the number of layers of the aluminum thin film and the titanium nitride film is the same, both being 3 layers.

[0033] In this embodiment, when visible light is incident on the plasmonic metasurface sensor of the present invention from directly above, it will cause the metasurface to excite the plasmon resonance phenomenon, and the plasmon resonance is further enhanced through the aluminum thin film and the titanium nitride film, expanding the optical near field and sensing regulation range in the detection of biomolecules in the plasmon mode, increasing the interaction range between light and matter, effectively improving the perception performance of substances, improving the accuracy of biological detection, and meeting the needs of a wide range of multi-marker detections. As Figure 3 shown, the resonance valleys are respectively located at positions of 232 nm, 360 nm, and 447 nm, and at the same time have a narrow full width at half maximum and a good quality factor, and have the strongest coupling efficiency at the position of 447 nm. As Figure 4 shown in (a) of Figure 4 shown in (b) of Figure 4 shown in (c) of , the electric field distributions in the plasmon resonance modes at wavelengths of 232 nm, 360 nm, and 447 nm, the electric field at 447 nm is tightly bound to the surface of the metal sensing area and is enhanced the most. Thus, it can be seen that the plasmonic metasurface sensor based on the alternating multi-nanometer stack of aluminum-titanium nitride can achieve multi-marker detection of substances on the metasurface.

[0034] Embodiment 2

[0035] Different from Embodiment 1, the thickness h3 of the aluminum thin film is 35 nm, and the thickness h4 of the titanium nitride film is 5 nm.

[0036] Referring to Figure 5 shown, the resonance valleys are respectively located at positions of 229 nm, 357 nm, and 446 nm, and at the same time have a narrow full width at half maximum and a good quality factor, and have the strongest coupling efficiency at the position of 446 nm. AsFigure 6 as shown in (a) of Figure 6 in (b) of Figure 6 and (c) of ,

[0037] Example 3

[0038] Different from Example 1, the thickness h3 of the aluminum thin film is 20 nm, and the thickness h4 of the titanium nitride film is 5 nm.

[0039] Refer to Figure 7 as shown in , Figure 8 the resonance valleys are respectively located at 227 nm, 352 nm, and 443 nm, and at the same time have a relatively narrow full width at half maximum and a good quality factor, and the strongest coupling efficiency is at 443 nm. As Figure 8 in (a) of Figure 8 in (b) of

[0040] and (c) of

[0041] Example 4

[0042] Refer to Figure 9 as shown in , Figure 10 the resonance valleys are respectively located at 276 nm, 431 nm, and 545 nm, and at the same time have a relatively narrow full width at half maximum and a good quality factor, and the strongest coupling efficiency is at 545 nm. As Figure 10 in (a) of Figure 10 in (b) of

[0043] In summary, the present invention solves the problem of limited optical near-field and sensing regulation range, thereby enhancing the detection ability of the sensor, meeting the wide demand for multi-marker detection, and opening up a broader application prospect in the field of optical sensing.

Claims

1. A plasmonic metasurface sensor based on alternating multi-nanometer stacks of aluminum-titanium nitride, characterized in that: It includes a substrate layer, multiple aluminum thin films, and multiple titanium nitride films; the aluminum thin films and the titanium nitride films are alternately arranged from bottom to top and are sequentially laminated on the substrate layer; periodic nanohole arrays are formed on the substrate layer; the number of layers of the aluminum thin films and the titanium nitride films is the same.

2. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The number of layers of the aluminum thin films and the titanium nitride films is 2 to 4 layers.

3. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The thickness of the aluminum thin film is 10 to 50 nm.

4. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The thickness of the titanium nitride film is 5 to 8 nm.

5. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The diameter of the nanohole is 200 to 300 nm.

6. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The depth of the nanohole is 200 to 300 nm.

7. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanometer stack as claimed in claim 1, wherein: The material of the substrate layer is a silicon substrate.

8. The plasmonic metasurface sensor based on an aluminum-titanium nitride alternating multi-nanolayer stack as claimed in claim 1, wherein: The size of the plasmonic metasurface sensor based on the aluminum-titanium nitride alternating multi-nano stack is 10 mm × 10 mm to 50 mm × 50 mm.

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