CN108226079A - The infrared double spectra devices of metallic graphite carbon alkene multilayer resonance structure enhancing Raman and preparation method - Google Patents

Abstract

A metal-graphene multilayer resonant structure enhanced Raman infrared dual-spectrum device includes a substrate, a metal reflection layer, a dielectric layer, a metal micro-antenna, a graphene film, and metal nanoparticles. The dielectric layer is located between the metal micro-antenna and the metal reflective layer, forming a metal-dielectric-metal reflective micro-antenna structure. The graphene film sits between the metal nanoparticles and the metal micro-antenna, forming a nanogap. Under the irradiation of infrared light, the antenna resonance effect of the metal micro-antenna is excited, and the infrared absorption spectrum signal of trace molecules is enhanced in a wide range of wavelengths. Under the laser irradiation in the visible light band, the local surface plasmons of metal nanoparticles are excited, and a high-intensity local electric field resonance mode is generated in the nano-gap between the metal nanoparticles and the metal micro-antenna, which enhances the Raman of trace molecules. scattered signal. The invention has the advantages of wide enhanced band, high enhanced factor, large-area processing, low cost, wide detection range of substances and the like.

Description

Metal graphene multilayer resonance structure enhanced Raman infrared dual spectrum device and its preparation method

technical field

The invention relates to the technical field of surface-enhanced spectroscopy, in particular to a device capable of achieving double enhancement of surface Raman spectrum and surface infrared absorption spectrum on a single device and a preparation method thereof.

Background technique

Surface-enhanced spectroscopy is a molecular spectroscopy detection technology developed based on the surface plasmon effect. It is a powerful tool for determining important information such as the composition and structure of biomolecules. It is used in food safety, environmental monitoring, chemical analysis and biomedicine. The field has broad application prospects. The most representative techniques are Surface-enhanced Raman scattering (SERS) and Surface-enhanced infrared absorption (SEIRA). Among them, the SERS technology can detect the change information of the polarizability caused by the vibration of the chemical bond in the molecule, and the SEIRA technology can detect the change information of the dipole moment caused by the vibration of the chemical bond in the molecule. Therefore, they are two complementary molecular techniques. Any single technique (SERS or SEIRA) can only detect part of the vibrational modes of molecules, and cannot simultaneously obtain information on the polarizability and dipole moment changes of molecules. In order to comprehensively obtain the structural information of biomolecules with various chemical bond vibration modes, the researchers combined the advantages of these two technologies and proposed a double-enhancement technology of surface Raman and infrared spectroscopy, which can realize the molecular polarizability and molecular polarization on the same substrate. Detection of dipole moment. There are currently two solutions.

One is to prepare metal nanoparticles to generate localized electromagnetic resonance modes in the visible and infrared bands. For the first time, NaomiJ.Halas et al. obtained double enhanced signals of SERS and SEIRA spectra by using the gold nanosphere shell structure array. In order to improve the morphology of nanoparticles, Wen-Bin Cai et al. prepared silver nanoparticle island films and realized the SEIRA and SERS spectral detection of heme. Monica Baia et al. obtained self-assembled gold nanoparticles by continuous deposition method, and realized the SERS and SEIRA spectral signal detection of p-aminothiophenol molecules. Jiannian Yao et al. assembled network-shaped gold nanoparticles, and the SERS enhancement factor for the tested molecules was 10 ⁶ , and the SEIRA enhancement factor was 10 ² . Although this type of method successfully achieves dual enhancement of SERS and SEIRA spectra on the same chip, the enhancement effect of SEIRA in the infrared band is poor, and its enhancement factor is only 10 ² .

The second is to design metal nano-antennas to generate local electromagnetic resonance modes in visible and infrared bands. In 2013, Cristiano D'Andrea et al. used electron beam lithography to design an array of gold nanoantenna structures. By changing the polarization direction of the excitation field, the antenna resonance effect of the antenna is excited in the infrared band, thereby producing a high-intensity sharp local electromagnetic resonance. peak. This method greatly increases the SEIRA enhancement factor of methylene blue molecule to 6×10 ⁵ . However, after the device is fabricated, its resonant frequency is fixed. The narrow spectral enhancement band cannot cover the mid-infrared characteristic fingerprint region, making the device only capable of SEIRA spectral detection for a few molecules. Meanwhile, the SERS enhancement factor of the substrate is only 10 ² .

In summary, although the above two methods can achieve the double enhancement effect of the Raman signal and the infrared absorption spectrum signal of the substance to be tested, they are all at the expense of one of the (SERS or SEIRA) enhancement factors , there is no guarantee that both the Raman signal and the infrared spectrum signal have a high enhancement factor.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention proposes a Raman infrared dual-spectrum device based on a metal graphene multilayer resonance structure and a preparation method, which combines metal nanoparticles with metal micro-antennas to respectively excite metal nanoparticles in the visible light band The local plasma effect and the antenna resonance effect of the metal micron antenna in the infrared band can realize the double enhancement effect of the Raman spectrum and the infrared absorption spectrum of the substance to be measured. It has the advantages of one-step detection of unknown molecules and can be used in environmental monitoring, food safety and other fields.

For solving the technical problem of the present invention, the technical scheme adopted is:

The Raman infrared dual-spectrum device based on a metal-graphene multilayer resonance structure includes a substrate, a metal reflective layer, a dielectric layer, a metal micro-antenna, a graphene film, and metal nanoparticles arranged sequentially from bottom to top.

The dielectric layer is located between the metal micro-antenna and the metal reflective layer, forming a metal-dielectric-metal reflective micro-antenna structure, and enhancing the SEIRA performance of the device in the infrared band.

The graphene film is located between the metal nanoparticles and the metal micro-antenna, forming a nano-gap, and enhancing the SERS performance of the device in the visible light band.

The metal micro-antenna is designed by designing micro-antenna arrays in different areas on the dielectric layer, and each area corresponds to a micro-antenna of a specific size, so that the micro-antenna has a specific resonance peak (corresponding to a resonance wavelength of λ). Realize the resonant peak of the antenna by designing multiple micron antenna array regions with incrementally changing parameters (for example: region 1, region 2,..., region 10, corresponding to the resonant wavelengths λ ₁ , λ ₂ ,..., λ ₁₀ , respectively) Distributed in the infrared range of 3-16 μm, it can generate antenna resonance effect under the excitation of infrared light waves, thereby generating a strong local electric field at the edge of the metal micro-antenna. When the resonance frequency of the antenna is consistent with the molecular vibration frequency of the substance to be detected, the electromagnetic field strength in the unit space around the molecule to be detected can be greatly enhanced, thereby realizing selective enhancement and wide-band detection of different vibration modes of the molecule to be detected in different regions . The number of said regions is 2 to 10, and the area of each region ranges from 200μm*200μm to 1mm*1mm; the pattern of the micron antenna array in each region is the same, and the pattern size and period parameters are different, according to the requirements parameter design.

The metal nanoprobe particles can generate localized surface plasmons under the excitation of visible light waves, thereby generating a strong local electric field around the metal nanoparticles, and further utilizing the graphene nano-gap to couple the metal nanoparticles to the metal micro-antenna, Improve the SERS performance of the device.

The dual-enhancement device detects the infrared absorption signal and the Raman scattering signal of the substance to be measured respectively, so as to comprehensively and accurately analyze the molecular structure of the substance to be measured.

Further, the metal micro-antenna is rectangular, square, circular, elliptical, hexagonal or cross-shaped in the transverse direction of the device. The size and period of the metal micro antenna range from 1 μm to 10 μm, and the thickness ranges from 20 to 200 nm.

Further, the graphene thin film has 1-10 layers, and the thickness is less than 5nm.

Further, the particle diameter of the metal nanoparticles ranges from 10 to 300 nm, and the metal material is selected from gold, silver, copper, and aluminum.

Further, the dielectric layer has a thickness ranging from 20 to 1000 nm, and is located between the metal micro-antenna and the metal reflective layer to form a reflective micro-antenna structure. The material of the dielectric layer is an infrared transparent material, which can be selected from: Al ₂ O ₃ , KBr, MgF ₂ , CaF ₂ , BaF ₂ , AgCl, ZnSe, SiO ₂ , and diamond-like carbon film.

The present invention further proposes a preparation method of the above enhanced Raman infrared dual-spectrum device. Include the following steps:

(1) Preparation of the metal reflective layer: a metal layer is deposited on the bottom of the sink by magnetron sputtering or electron beam evaporation as a reflective layer.

(2) Preparing a dielectric layer: depositing a dielectric layer on the metal reflective layer by means of electron beam evaporation, atomic deposition or molecular beam epitaxy.

(3) Preparation of metal micro-antennas: Utilize ultraviolet lithography, laser direct writing and other photolithography technologies, combined with electron beam evaporation, magnetron sputtering, thermal evaporation and other methods to deposit metal micro-antennas on the dielectric layer.

(4) Transfer graphene thin film: use mechanical exfoliation process or chemical vapor deposition method to prepare graphene thin film, and transfer the prepared graphene to the metal micro-antenna. The number of layers of the graphene film is 1-10 layers, and the multi-layer structure can be realized by directly growing multi-layer graphene or multiple transfer methods.

(5) Preparation of metal nanoparticles: deposit metal nanoparticles on the graphene film by electron beam evaporation, magnetron sputtering, thermal evaporation and other methods. Further, the metal nanoparticles can be deposited at a slow rate by electron beam evaporation, magnetron sputtering, thermal evaporation It can be directly obtained by deposition, and the deposited metal thickness ranges from 3 to 20nm; the size of metal nanoparticles can also be controlled by high temperature (300-500°C) annealing, and the particle size range is 10-300nm; the metal material is selected from gold, silver, copper, aluminum.

Compared with the prior art, the present invention has the following advantages:

First, the double-enhanced device of the present invention adopts a bottom-up processing method, and the preparation method of metal micro-antenna and metal nanoparticles is compatible with the standard microlithography process and coating process, and has the advantages of simple processing technology and mass production obvious advantage.

Second, the present invention can accurately control the resonance wavelength of the metal micron antenna in the infrared band by precisely controlling the size and period parameters of the metal micron antenna. The local area of the light wave, so as to achieve the maximum enhancement effect of the infrared spectrum signal of the substance to be measured; at the same time, by designing metal micron antennas with different sizes and period parameters on different regions of the same substrate, it can generate resonance modes, so as to realize the Broadband enhanced detection of matter.

Third, graphene, as a two-dimensional material, has a thickness of only 0.34nm. The present invention uses graphene as a sub-nanometer interlayer, which is sandwiched between metal nanoparticles and metal micro-antennas to form a nano-gap, so that the metal nanoparticles not only There is mode coupling between nanoparticles in the horizontal direction, and coupling between metal nanoparticles and metal micro-antennas in the vertical direction, which can greatly enhance the SERS performance of the device. Meanwhile, the chemical enhancement caused by π-π stacking and charge transfer between graphene and molecules also has a certain promotion effect on SERS.

Fourth, the present invention realizes the measurement of trace molecular Raman spectrum and infrared spectrum signals at the same time in the same device, avoiding the steps of re-making devices and samples when changing the measurement method, and can realize the complete measurement of trace molecular vibration information , to speed up the sample detection speed and improve work efficiency.

It can be seen that the present invention can realize the double enhancement of surface Raman spectrum and surface infrared spectrum at the same time, and has the advantages of high sensitivity, good stability, large-area processing, wide-band enhanced detection, etc., and has broad application prospects.

Description of drawings

Fig. 1 is a schematic diagram of a metal graphene multilayer resonance structure enhanced Raman infrared dual-spectrum device;

Fig. 2 is a schematic diagram including a plurality of different regions on the same device;

Fig. 3 (a)-Fig. 3 (f) are rectangle, square, disc shape, ellipse, hexagon, the metal micron antenna schematic diagram of cross shape;

Fig. 3 (g) is the three-dimensional schematic diagram of the metal micron antenna when the cross section is a square;

Fig. 4 is the preparation flowchart of metal graphene multilayer resonant structure enhanced Raman infrared double spectrum method and device;

Fig. 5 (a) is the SEM picture of micron rectangular gold grating/aluminum oxide/gold reflective layer reflective micron antenna structure;

Fig. 5 (b) is the SEM picture of graphene and silver nanoparticles covering the reflective micro-antenna structure;

Fig. 6 (a) is the particle size distribution figure of silver nanoparticles;

Fig. 6 (b) is the ultraviolet-visible absorption spectrum of different size silver nanoparticles;

Figure 7(a) is the Raman spectrum of the double-enhanced device after silver nanoparticles with different particle sizes;

Fig. 7 (b) is the average Raman spectrum of the rhodamine R6G solution of different molecular concentrations;

Figure 8(a) is the reflectance spectrum of the dual enhancement device under different grating linewidth conditions;

Figure 8(b) is the reflectance spectrum of the double-enhanced device under different grating linewidth conditions after spin-coating ethylene oxide PEO;

Figure 8(c) is the enhanced vibrational signal curve of PEO molecules after baseline treatment.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clear, preferred examples of the present invention will be further described in detail below in conjunction with the accompanying drawings. The same reference numerals in the drawings represent the same or similar components.

Referring to Fig. 1, the metal graphene multilayer resonant structure enhanced Raman infrared dual-spectrum device designed by the present invention includes a substrate 1, a metal reflective layer 2, a dielectric layer 3, a metal micro-antenna 4, and a graphene Thin films 5 and metal nanoparticles 6 . During the test, the detection substance 7 to be tested is placed on the device by means of spray coating, spin coating or the like. The medium layer 3 is located between the metal micron antenna 4 and the metal reflective layer 2, forming a metal-medium-metal reflective micron antenna structure. The thickness of the medium layer 3 is in the range of 20 to 1000 nm, and the material of the medium layer is an infrared transparent material, which can be Selected from: Al ₂ O ₃ , KBr, MgF ₂ , CaF ₂ , BaF ₂ , AgCl, ZnSe, SiO ₂ , diamond-like carbon film. The number of layers of the graphene film 5 is 1 to 10 layers, located between the metal nanoparticles 6 and the metal micro-antenna 4, forming a nano-gap, coupling the metal nanoparticles and the metal micro-antenna, and improving the SERS performance of the device . The particle size range of the metal nanoparticles 6 is 10-300nm, and the metal material is selected from gold, silver, copper, and aluminum.

In the above structure, the metal micro-antenna 4 can produce an antenna resonance effect under the excitation of infrared light waves, thereby generating a strong local electric field at the edge of the metal micro-antenna 4 . Further, by designing micro-antenna arrays with different structures in different regions on the dielectric layer 3, the resonant peaks of the metal micro-antenna 4 are distributed in the infrared range of 3-16 μm. When the resonance frequency of the antenna is consistent with the molecular vibration frequency of the substance to be detected, the electromagnetic field strength in the unit space around the molecule to be detected can be greatly enhanced, thereby achieving selective enhancement and wide band of different vibration modes of the molecule to be detected in different regions probing. The metal nanoprobe particle 6 can generate localized surface plasmons under the excitation of visible light waves, thereby generating a strong local electric field around the metal nanoparticle 6, and further utilizing the graphene nanogap to make the metal nanoparticle 6 and the metal micro-antenna 4 interact Coupling improves the SERS performance of the device. By separately detecting the infrared vibration signal and the Raman scattering signal of the substance 7 to be measured, the molecular structure of the substance 7 to be measured can be fully and accurately analyzed.

Referring to Figure 2, the number of regions is 2 to 10, and the area of each region ranges from 200μm*200μm to 1mm*1mm; the micron antenna array pattern in each region is the same, and the structure size and period parameters are different. Same. Each area corresponds to a micron antenna of a specific size, so that the micron antenna has a specific resonance peak (corresponding to a resonance wavelength of λ). By designing multiple micron antenna array areas with incrementally changing parameters. For example: area 1, area 2, ..., area 10, respectively corresponding to resonance wavelengths λ ₁ , λ ₂ , ..., λ ₁₀ . To realize the distribution of the resonant peak of the antenna in the infrared range of 3-16 μm.

The shape of the metal micro antenna 4 is selected according to actual needs, and can be one or more combinations of rectangle, square, circle, ellipse, hexagon, cross, etc. Figures 3(a) to 3(f) are cross-sectional views of the metal micro-antenna in the transverse direction of the dual booster device, and Figure 3(g) shows a three-dimensional schematic diagram of the micro-antenna structure with a square cross-section. The size and period of the metal micro antenna range from 1 μm to 10 μm, and the thickness ranges from 20 to 200 nm.

Fig. 4 is the flowchart of preparing metal graphene multilayer resonant structure enhanced Raman infrared dual-spectrum device:

Step S1: preparing a metal reflective layer. A metal layer is deposited on the substrate 1 as the metal reflective layer 2 by means of magnetron sputtering or electron beam evaporation.

Step S2: preparing a medium layer. The dielectric layer 3 is deposited on the metal reflective layer 2 by means of electron beam evaporation, atomic deposition or molecular beam epitaxy.

Step S3: preparing the metal micro-antenna. Using micro-lithography techniques such as ultraviolet lithography and laser direct writing, combined with methods such as electron beam evaporation, magnetron sputtering, and thermal evaporation, the metal micro-antenna 4 is deposited on the dielectric layer. The shape of the metal micro antenna 4 can be selected from one or more combinations of rectangle, square, circle, ellipse, hexagon, cross, etc. The size and period of the metal micro antenna range from 1 μm to 10 μm, and the thickness range is 20-200nm.

Step S4: transferring the graphene film. Graphene thin film 5 is prepared by mechanical exfoliation process or chemical vapor deposition method, and the prepared graphene is transferred to the metal micro antenna 4; the number of layers of graphene thin film 5 is 1 to 10 layers, and the multilayer structure can be directly grown Realized by multi-layer graphene or multiple transfer methods;

Step S5: preparing metal nanoparticles. Metal nanoparticles 6 are deposited on the graphene film 5 by means of electron beam evaporation, magnetron sputtering, thermal evaporation and the like. Metal nanoparticles 6 can be deposited at a slow rate by electron beam evaporation, magnetron sputtering, thermal evaporation It is directly obtained by deposition, and the thickness of the deposited metal is in the range of 3-20nm. The size of the metal nanoparticles 6 can also be controlled by high-temperature (300-500°C) annealing. The particle size ranges from 10-300nm, and the metal material is selected from gold and silver. , copper, aluminum.

Step S6: placing the substance to be tested 7 on the device by means of spray coating, spin coating, or the like.

The implementation principles and expected effects of the present invention will be further described below in conjunction with the embodiments. However, the present invention is not limited to the exemplary embodiments disclosed below, and those skilled in the relevant art can implement it in various forms. The essence of the description is only to help those skilled in the relevant art comprehensively understand the specific details of the present invention.

In this example, taking micron rectangular gold gratings and silver nanoparticles as examples, 50nm Au and 300nm Al ₂ O ₃ were first deposited on a Si substrate based on magnetron sputtering, and then prepared on the same substrate by standard photolithography and electron beam evaporation. Rectangular gold gratings with different line widths are used to obtain a micron rectangular gold grating-aluminum oxide-gold reflective layer reflective micron antenna structure. The period of the grating is fixed at 6 μm, the line width is gradually increased from 2.0 μm to 3.6 μm in steps of 0.4 μm, and the thickness of the grating is 20 nm. Figure 5(a) shows the SEM image of a grating with a period of P=6 μm and a line width of w=3 μm. Single-layer graphene was then grown on Cu foil by chemical vapor deposition (CVD), and poly(methyl methacrylate) (PMMA) was used as a transfer agent to transfer the graphene to the surface of the reflective micron antenna grating structure. Finally, with The evaporation rate of silver nanoparticles was deposited on graphene, and the particle size of silver nanoparticles was controlled by controlling the deposition time. Figure 5(b) is the SEM image of the substrate after 5nm silver was evaporated. It can be seen from the figure that silver does not form a continuous film, but forms island-shaped nanoparticles.

Fig. 6(a) is a particle size distribution diagram of the silver nanoparticles on the surface of the substrate. By counting the diameters of about 300 silver nanoparticles in the SEM images, we calculated that the average diameter of the silver nanoparticles on the surface of the substrate was about 45 nm. Using the same method, silver nanoparticles with particle sizes of 35nm and 55nm were obtained. The ultraviolet-visible absorption spectrum of the prepared silver nanoparticles on the quartz substrate is shown in Fig. 6(b). It can be seen from the figure that the silver nanoparticles generate localized surface plasmons under the excitation of visible light waves, resulting in strong absorption in the visible light band. With the increase of the particle size of silver nanoparticles, its resonance wavelength red shifts. When the average diameter of silver nanoparticles is 45nm, the plasmon peak of silver nanoparticles is the closest to the Raman test laser wavelength of 532nm, so it can be used in the spectrum test. Maximize the Raman activity of the device.

Figure 7(a) shows the Raman spectrum of the double-enhanced device after evaporating silver nanoparticles with different particle sizes. From the figure, the Raman characteristic peaks of graphene can be clearly observed: the G peak at 1580cm ^-1 , the G peak at 2685cm 2D peak at ⁻¹ , and D peak at 1334 cm ⁻¹ . The ratio of the 2D peak to the G peak is about 2, and the D peak is not obvious, indicating that the graphene in the device is a single-layer graphene, and no large defects are introduced due to the deposition of silver nanoparticles on its surface. At the same time, it can be seen from the figure that when the average diameter of the silver nanoparticles is about 45nm, the enhancement effect of the silver nanoparticles on the Raman characteristic peaks of graphene is the greatest.

Example Rhodamine 6G (R6G), a typical organic analyte, was used as a probe molecule, its aqueous solution was sprayed onto the sample, and then dried in air for 2 minutes to immobilize the molecule on the surface of the device. Figure 7(b) shows the average Raman spectra of R6G solutions with different molecular concentrations sprayed on the double-enhancement device, and the average diameter of silver nanoparticles is 45 nm. Various Raman characteristic peaks of R6G can be observed from the figure, including: 1650, 1574, 1509, 1362, 1312, 1182, 772 and 612cm ^-1 , which are consistent with the results reported in the literature. At the same time, when the molecular concentration is as low as 10 ^-12 M, the Raman signal of R6G can still be observed, and the calculated SERS enhancement factor can reach 10 ⁷ , which indicates that the prepared double-enhanced device has a good Raman enhancement effect.

Figure 8(a) shows the reflectance spectra of the dual-enhancement device with different grating linewidths. It can be seen from the figure that the gold rectangular grating produces an antenna resonance effect under the excitation of infrared light waves, resulting in strong absorption in the infrared region; as the line width w gradually increases from 2.0 μm to 3.6 μm, the plasmon peak increases from 1350 cm ^-1 (7.4μm) red shifted to 1050cm ^-1 (9.5μm). Figure 8(b) shows the reflectance spectrum of the double-enhanced device when polyethylene oxide (PEO) is used as the probe molecule. It can be seen from the figure that the spectral curve of the device after spin-coating PEO on the surface has a small red shift relative to the spectral curve of the bare device. At the same time, some obvious protrusions can be seen on the resonance peaks, which represent various molecular vibration modes of PEO molecules. Further through the baseline processing, the enhanced vibration signal curve of the PEO molecule itself is obtained, as shown in Fig. 8(c). It can be seen from the figure that the prepared dual-enhancement device can enhance each vibration mode of PEO molecules in the frequency range of 800-1500 cm ^-1 , and when the vibration frequency of PEO molecules is close to the resonant frequency of the metal micro-antenna, the double-enhancement device It has the greatest effect on enhancing the vibration signal of PEO molecules. For example, for the vibration mode at 1278cm ^- 1, when the grating line width is 2.4um, the plasmon resonance frequency is consistent with this vibration mode, and the enhancement effect of the double enhancement device on this mode is the largest. As the linewidth of the grating increases, the resonance peak is red-shifted, causing the plasmon resonance frequency to move away from the vibration mode, and the enhancement effect gradually decreases. Therefore, by controlling the parameters of the grating structure, the vibrational modes of PEO molecules can be selectively enhanced to achieve broadband detection. It is calculated that the enhancement factor of the double enhancement device to the PEO infrared spectrum signal can reach up to 8×10 ⁵ .

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not limit them. Although the present invention has been described in detail through the above embodiments, those skilled in the art should understand that the description and embodiments are only considered as Rather, various changes may be made in form and detail, and the true scope and spirit of the invention are defined by the claims.

Claims (10)

1. A metal graphene multilayer resonant structure enhanced Raman infrared dual-spectrum device is characterized in that: it comprises a substrate, a metal reflection layer, a dielectric layer, a metal micro-antenna, a graphene thin film, and a metal layer that are arranged successively from bottom to top. nanoparticles; The dielectric layer is located between the metal micro-antenna and the metal reflective layer, forming a metal-medium-metal reflective micro-antenna structure, and enhancing the infrared spectrum performance of the surface of the device in the infrared band; The graphene film is located between the metal nanoparticles and the metal micro-antenna, forming a nano-gap, and enhancing the Raman spectrum performance of the surface of the device in the visible band; The metal micro-antenna is a micro-antenna array with different structures designed in different regions on the dielectric layer, so that the resonant peaks of the metal micro-antenna are distributed in the wide-band infrared range, and the metal micro-antenna generates an antenna resonance effect under the excitation of infrared light waves, Therefore, a strong local electric field is generated at the edge of the metal micro-antenna. When the resonance frequency of the antenna is consistent with the molecular vibration frequency of the substance to be detected, the vibration signal strength of the measured molecule is greatly enhanced; the pattern of the micro-antenna array in each area is the same , the specific size and period parameters change linearly and incrementally, so as to achieve selective enhancement and wide-band detection of different vibration modes of the molecules to be tested in different regions; The metal nano-probe particles generate local surface plasmons under the excitation of visible light waves, thereby generating a strong local electric field around the metal nanoparticles, and further utilize graphene nano-gap to couple the metal nanoparticles to the metal micro-antenna , to further improve the surface-enhanced Raman spectroscopy performance of the device. 2. The enhanced Raman infrared dual-spectrum device according to claim 1, characterized in that: the metal micro-antenna is rectangular, square, circular, elliptical, hexagonal or cross-shaped in the transverse direction of the device ; The size and period of the metal micro-antenna range from 1 μm to 10 μm, and the thickness range from 20 to 200 nm. 3. the enhanced Raman infrared dual-spectrum device according to claim 1, characterized in that: the micron antenna arrays of different regions are designed on the dielectric layer, and each region corresponds to a micron antenna of a size, so that the micron antenna has a The corresponding resonant peak, the resonant wavelength is λ, and the resonant peak of the antenna is distributed in the infrared range of 3-16 μm by designing multiple micron antenna array areas with incrementally changing parameters; the number of said areas is 2-10, each The area of the region ranges from 200 μm*200 μm to 1 mm*1 mm. 4. The enhanced Raman infrared dual-spectrum device according to claim 1, characterized in that: the graphene thin film has 1-10 layers. 5 . The enhanced Raman infrared dual-spectrum device according to claim 1 , characterized in that: the particle size range of the metal nanoparticles is 10-300 nm, and the metal material is selected from gold, silver, copper, and aluminum. 6. The enhanced Raman infrared dual-spectrum device according to claim 1, characterized in that: the thickness range of the dielectric layer is: 20-1000nm, and it is located between the metal micro-antenna and the metal reflective layer to form a reflective micro-antenna structure ; The material of the dielectric layer is an infrared transparent material selected from: Al ₂ O ₃ , KBr, MgF ₂ , CaF ₂ , BaF ₂ , AgCl, ZnSe, SiO ₂ , and diamond-like carbon film. 7. the preparation method of the enhanced Raman infrared dual-spectrum device of claim 1, is characterized in that, comprises the step: (1) Prepare metal reflective layer: deposit a layer of metal layer on the substrate as reflective layer; (2) Preparing a dielectric layer: depositing a dielectric layer on the metal reflective layer; (3) Preparation of metal micro-antenna: adopt photolithography technology to prepare metal micro-antenna on the dielectric layer; (4) transfer graphene film: the prepared graphene is transferred to the metal micron antenna; (5) Preparation of metal nanoparticles: deposit metal nanoparticles on the graphene film. 8. the preparation method of enhanced Raman infrared dual-spectrum device according to claim 7, is characterized in that: described metal micro-antenna utilizes photolithography technologies such as ultraviolet lithography, laser direct writing, combines electron beam evaporation, magnetic Controlled sputtering, thermal evaporation and other methods obtained. 9. the preparation method of enhanced Raman infrared dual-spectrum device according to claim 7, is characterized in that: described graphene thin film utilizes mechanical exfoliation process or chemical vapor deposition method to prepare; The number of layers of described graphene thin film It can be achieved by direct growth of multilayer graphene or multiple transfer methods. 10. the preparation method of enhanced Raman infrared dual-spectrum device according to claim 7, is characterized in that: described metal nanoparticle is evaporated by electron beam, magnetron sputtering, thermal evaporation at a slow rate The deposition is directly obtained; the metal nano particles are further controlled by 300-500° annealing to control the size of the metal nanoparticles.