Metal metasurface composite multilayer film compatible with microwave high transmission effect

Abstract

The invention relates to a metal metasurface composite multilayer film compatible with a microwave high transmission effect. According to the technical scheme, the metal metasurface composite multilayer film compatible with the microwave high-transmission effect is formed by compounding an upper-layer metal periodic array structure and a lower-layer multilayer film structure; the structural design expression of the metal metasurface composite multilayer film compatible with the microwave high transmission effect is # imgabs0 #, # imgabs1 # represents a multilayer film structure, n represents the combination number, n is larger than or equal to 1 and smaller than or equal to 4, and n is a positive integer; i represents a combination ordinal number, 1 < = i < = n, and i is a positive integer; a0 represents an A material thin film of a bottom layer in the multi-layer film structure; m represents a metal periodic array structure. The metal periodic array structure is a latticed array formed by arranging the same metal units according to rows and columns at equal intervals. The invention has the characteristics of few layers, thin thickness, high infrared reflectivity, stable infrared reflectivity, wide material selection range and compatible microwave high transmission effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal super-surface composite multilayer films, and specifically relates to a metal super-surface composite multilayer film compatible with microwave high transmittance effect. Background Art

[0002] When electromagnetic waves pass through the atmosphere, they are absorbed and reflected by various gas molecules, water molecules, and even dust in the atmosphere. In the infrared field, most of the infrared radiation in the band is completely absorbed by various substances in the atmosphere, while the 3-5μm and 8-14μm bands still retain a high infrared transmittance. This part of the band is called the "atmospheric window". Because of the existence of the "atmospheric window", the infrared signal of the object in this band cannot be naturally attenuated in the air, and can be detected by various infrared detectors.

[0003] Composite film materials, mainly represented by photonic crystals and multilayer films, can use the periodic structure of photonic crystals to form a photonic bandgap, preventing light waves of specific wavelengths from passing through, thereby achieving high reflection of infrared light; while multilayer films can flexibly control the thickness of two or more materials with different refractive indices and extinction coefficients to achieve high transmittance of specific electromagnetic waves.

[0004] For example, Tong et al. (Tong, H. et al. Achievement of low infrared emissivity photonic crystal design on [CdSe / SiO2]N periodic films. Optics & Laser Technology 156, doi: 10.1016 / j.optlastec.2022.108557 (2022).) proposed a periodic one-dimensional photonic crystal, which consists of a layer of CdSe film and a layer of SiO2 film as a period. The thickness of a period is about 2.44 μm. By superimposing 5 to 9 periods, the reflectivity in the infrared 3-5 μm and 8-14 μm bands exceeds 95%. However, CdSe materials are relatively scarce and are not suitable for mass production.

[0005] Zhu et al. (Zhu, H. et al. Multispectral camouflage for infrared, visible, lasers and microwave with radiative cooling. Nature Communications 12, doi: 10.1038 / s41467-021-22051-0 (2021).) designed a multispectral camouflage device, which is composed of a ZnS / Ge multilayer film and a Cu-ITO-Cu supersurface composite. At 100°C, the band emittance measured in the mid- and far-infrared is 0.11 / 0.12, and the band emittance of the non-atmospheric window (5-8μm) is 0.61. It also has high laser absorption effects at 1.55μm and 10.6μm. However, its laser absorption function at 10.6μm causes low infrared reflection in the adjacent interval. At the same time, the infrared reflectivity of the structure fluctuates greatly at about 4μm, and it is impossible to maintain a stable high reflection interval in the entire working band.

[0006] Another example is the patented technology of "an infrared stealth material" (CN 106383376A). This technology uses ZnSe and YbF3 as high-refractive index materials and low-refractive index materials for alternating coating. The overall film layer reaches 33 layers and the total thickness reaches 21.52μm. After simulation, it is found that although the design has an average emissivity of more than 95% in the 5-7.5μm band, it has too many layers and is too thick, making it difficult to prepare.

[0007] The patented technology of "one-dimensional metal-enhanced film structure with low number of layers and high reflectivity in the mid-to-far infrared" (CN108873111A) is composed of three one-dimensional λ / 4 periodic photonic crystal structures and a metal-enhanced layer structure, with a total of 23 layers. It can achieve a reflectivity between 95% and 99.999% in the infrared bands of 3-5μm and 8-14μm. However, simulation results show that the metal-enhanced layer greatly increases the microwave reflectivity, which is not conducive to concealment in the microwave field. At the same time, the design also has the disadvantages of having a large number of layers and complex processes.

[0008] In summary, the prior art has the following technical defects: thick layers, complex processes, narrow material selection, low infrared reflectivity, unstable reflectivity, and the use of metal materials resulting in excessive microwave reflectivity. Summary of the invention

[0009] The present invention aims to overcome the defects of the prior art and aims to provide a metal super-surface composite multilayer film with few layers, thin thickness, simple process, high infrared reflectivity, stable infrared reflectivity, wide material selection and compatibility with microwave high transmittance effect.

[0010] To achieve the above object, the technical solution adopted by the present invention is:

[0011] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0012] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0013]

[0014] In formula (1):

[0015] Represents a multilayer film structure, where:

[0016] A0 represents the bottom A material film in the multilayer film structure;

[0017] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i Thin material

[0018] The upper surface of the membrane is close to A i the lower surface of the material film;

[0019] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0020] B i represents the B material film of the ith combination in the multilayer film structure;

[0021] A i represents the A material film of the ith combination in the multilayer film structure;

[0022] n represents the number of combinations, 1≤n≤4, n is a positive integer;

[0023] i represents the combination ordinal number, 1≤i≤n, i is a positive integer;

[0024] M represents a metal periodic array structure.

[0025] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing; the shape of the metal units is one of a circle, a polygon and a ring, and the spacing is 0.05 to 5 mm.

[0026] The area of ​​the metal unit is 0.1 to 10 mm 2 .

[0027] The metal in the metal periodic array structure is one of Au, Cu, Pt, Ag, Ti and Mo.

[0028] The thickness of the metal periodic array structure is 0.01-2 μm.

[0029] The material of the A material film in the multi-layer film structure is one of Ge and Si.

[0030] The material of the B material film in the multi-layer film structure is one of SiO2, ZnO and ZnS.

[0031] The A i The thickness of the material film is 0.01 to 1 μm.

[0032] The thickness of the A material film of the bottom layer is 0.01-1 μm.

[0033] The B i The thickness of the material film is 0.01 to 1 μm.

[0034] Due to the adoption of the above technical solution, the present invention has the following positive effects compared with the prior art:

[0035] 1. The present invention aims to solve the problem that existing non-metallic multilayer film materials need to have large thickness and high number of layers to achieve high infrared reflectivity. The present invention introduces a metal material with stable high infrared reflectivity as the upper layer material. When electromagnetic waves are incident on the upper metal material containing a large number of free electrons, the changing magnetic field will generate an electric field, which will cause the vibration of the free electrons to generate infrared radiation and achieve high infrared reflectivity. The simulation results show that when the thickness of the upper metal periodic array structure is 0.1μm, the infrared reflectivity of the overall structure can be greatly increased to more than 85% and the effect is stable, which can significantly improve the infrared reflectivity and stability of the metal super-surface composite multilayer film compatible with microwave high transmittance.

[0036] 2. In order to address the shortcoming of metal materials in the prior art that they can cause high microwave reflection, the present invention adopts a metal periodic array structure, that is, there are sub-wavelength intervals of microwaves between adjacent metal units. Such sub-wavelength intervals increase the transmittance of microwaves, that is, due to the coupling effect between surface plasmons and light, light can pass through these sub-wavelength gaps with a higher transmittance, thus overcoming the high reflection shortcoming of existing metal materials in the microwave field and significantly improving the microwave transmission and infrared reflection effects of the metal super-surface composite multilayer film that is compatible with high microwave transmission effects.

[0037] 3. The upper metal periodic array structure of the present invention can achieve high infrared reflection effect, and the material selection of the lower multilayer film structure can be selected from low-cost common materials, and is no longer limited to precious and scarce materials such as Si, SiO2, ZnO and ZnS. These materials have good mechanical properties and temperature resistance. Therefore, they can not only significantly improve the mechanical properties and temperature resistance of the metal super-surface composite multilayer film compatible with microwave high transmittance effect, but also have a wider range of material selection.

[0038] 4. The thickness of the upper metal periodic array structure used in the present invention is 0.01-2 μm, the lower multilayer film structure is 0.09-9 μm, the maximum thickness of the metal supersurface composite multilayer film is 11 μm, and the maximum number of layers is 10. Therefore, the present invention has a small number of layers and a thin thickness, which simplifies the process. Simulation results show that the infrared reflectivity of the present invention in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of more than 95% for 2-18 GHz microwaves.

[0039] Therefore, the present invention has the characteristics of few layers, thin thickness, simple process, high infrared reflectivity, stable infrared reflectivity, wide material selection and compatibility with high microwave transmittance effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of the structure of a metal super-surface composite multilayer film compatible with microwave high transmittance effect of the present invention;

[0041] Figure 2 for Figure 1 The infrared reflectivity simulation comparison diagram of the metal super-surface composite multilayer film compatible with microwave high transmittance effect and its underlying multilayer film structure;

[0042] Figure 3 for Figure 1 The microwave transmittance simulation effect diagram of the metal supersurface composite multilayer film compatible with high microwave transmittance effect is shown. DETAILED DESCRIPTION

[0043] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods, but is not intended to limit the protection scope of the present invention.

[0044] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0045] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0046] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0047]

[0048] In formula (1):

[0049] Represents a multilayer film structure, where:

[0050] A0 represents the bottom A material film in the multilayer film structure;

[0051] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i Thin material

[0052] The upper surface of the membrane is close to A i the lower surface of the material film;

[0053] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0054] B i represents the B material film of the ith combination in the multilayer film structure;

[0055] A i represents the A material film of the ith combination in the multilayer film structure;

[0056] n represents the number of combinations, 1≤n≤4, n is a positive integer;

[0057] i represents the combination ordinal number, 1≤i≤n, i is a positive integer;

[0058] M represents a metal periodic array structure.

[0059] For the sake of simplicity, the “metal super-surface composite multilayer film compatible with microwave high transmittance effect” is referred to as “metal super-surface composite multilayer film” (the same below);

[0060] When n=1, the metal super surface composite multilayer film has 4 layers, and the metal super surface composite multilayer film structure is

[0061] The calculation expression is:

[0062]

[0063] When n=2, the metal super surface composite multilayer film has 6 layers, and the metal super surface composite multilayer film structure is

[0064] The calculation expression is:

[0065]

[0066] When n=3, the metal super surface composite multilayer film has 8 layers, and the metal super surface composite multilayer film structure is

[0067] The calculation expression is:

[0068]

[0069] When n=4, the metal super surface composite multilayer film has 10 layers, and the metal super surface composite multilayer film structure is

[0070] The calculation expression is:

[0071]

[0072] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is one of a circle, a polygon and a ring, and the spacing is 0.05 to 5 mm.

[0073] The metal in the metal periodic array structure is one of Au, Cu, Pt, Ag, Ti and Mo.

[0074] The thickness of the metal periodic array structure is 0.01-2 μm.

[0075] The material of the A material film in the multi-layer film structure is one of Ge and Si.

[0076] The material of the B material film in the multi-layer film structure is one of SiO2, ZnO and ZnS.

[0077] The A i The thickness of the material film is 0.01 to 1 μm.

[0078] The thickness of the A material film of the bottom layer is 0.01-1 μm.

[0079] The B i The thickness of the material film is 0.01 to 1 μm.

[0080] Example 1

[0081] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0082] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0083] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0084]

[0085] In formula (1):

[0086] Represents a multilayer film structure, where:

[0087] A0 represents the bottom A material film in the multilayer film structure;

[0088] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i Thin material

[0089] The upper surface of the membrane is close to A i the lower surface of the material film;

[0090] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0091] B i represents the B material film of the ith combination in the multilayer film structure;

[0092] A i represents the A material film of the ith combination in the multilayer film structure;

[0093] n represents the number of combinations, n=4;

[0094] i represents the combination ordinal number, 1≤i≤n, i is a positive integer;

[0095] M represents a metal periodic array structure.

[0096] In this embodiment, n=4. From formula (1), the structural design expression of the metal supersurface composite multilayer film is:

[0097]

[0098] In formula (2):

[0099] A0 represents the bottom A material film in the multilayer film structure;

[0100] B1 represents the B material film of the first group in the multilayer film structure;

[0101] A1 represents the A material film of the first group in the multilayer film structure;

[0102] B2 represents the B material film of the second group in the multilayer film structure;

[0103] A2 represents the A material film of the second group in the multilayer film structure;

[0104] B3 represents the B material film of the third group in the multilayer film structure;

[0105] A3 represents the A material film of the third group in the multilayer film structure;

[0106] B4 represents the B material film of the 4th group in the multilayer film structure;

[0107] A4 represents the A material film of the 4th group in the multilayer film structure;

[0108] M represents a metal periodic array structure.

[0109] In this embodiment, the multilayer film structure is a 9-layer structure consisting of a bottom A material film and 4 combinations, and the metal supersurface composite multilayer film is 10 layers.

[0110] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is square, and the spacing is 0.1 mm.

[0111] The area of ​​the metal unit is 0.25 mm 2 .

[0112] The metal in the metal periodic array structure is Au.

[0113] The thickness of the metal periodic array structure is 0.1 μm.

[0114] The material of the A material film in the multi-layer film structure is Ge.

[0115] The material of the B material film in the multi-layer film structure is ZnO.

[0116] The thickness of the A1 material film is 0.546 μm.

[0117] The thickness of the A2 material film is 0.114 μm.

[0118] The thickness of the A3 material film is 0.3 μm.

[0119] The thickness of the A4 material film is 0.286 μm.

[0120] The thickness of the A material film of the bottom layer is 0.054 μm.

[0121] The thickness of the B1 material film is 0.45 μm.

[0122] The thickness of the B2 material film is 0.29 μm.

[0123] The thickness of the B3 material film is 0.8 μm.

[0124] The thickness of the B4 material film is 0.126 μm.

[0125] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0126] Example 2

[0127] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0128] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0129] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0130]

[0131] In formula (1):

[0132] Represents a multilayer film structure, where:

[0133] A0 represents the bottom A material film in the multilayer film structure;

[0134] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i Thin material

[0135] The upper surface of the membrane is close to A i the lower surface of the material film;

[0136] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0137] B i represents the B material film of the ith combination in the multilayer film structure;

[0138] A i represents the A material film of the ith combination in the multilayer film structure;

[0139] n represents the number of combinations, n = 2;

[0140] i represents the combination ordinal number, 1≤i≤n, i is a positive integer;

[0141] M represents a metal periodic array structure.

[0142] In this embodiment, n=2, and from formula (1), the structural design expression of the metal supersurface composite multilayer film is:

[0143]

[0144] In formula (2):

[0145] A0 represents the bottom A material film in the multilayer film structure;

[0146] B1 represents the B material film of the first group in the multilayer film structure;

[0147] A1 represents the A material film of the first group in the multilayer film structure;

[0148] B2 represents the B material film of the second group in the multilayer film structure;

[0149] A2 represents the A material film of the second group in the multilayer film structure;

[0150] M represents a metal periodic array structure.

[0151] In this embodiment, the multilayer film structure is a 5-layer structure consisting of a bottom A material film and two combinations, and the metal supersurface composite multilayer film is 6 layers.

[0152] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is ring-shaped, and the spacing is 0.05 mm.

[0153] The area of ​​the metal unit is 0.2 mm 2 .

[0154] The metal in the metal periodic array structure is Cu.

[0155] The thickness of the metal periodic array structure is 0.03 μm.

[0156] The material of the A material film in the multi-layer film structure is Si.

[0157] The material of the B material film in the multi-layer film structure is ZnO.

[0158] The thickness of the Al material film is 0.03 μm.

[0159] The thickness of the A2 material film is 0.02 μm.

[0160] The thickness of the A material film of the bottom layer is 0.03 μm.

[0161] The thickness of the B1 material film is 0.04 μm.

[0162] The thickness of the B2 material film is 0.03 μm.

[0163] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0164] Example 3

[0165] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0166] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0167] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0168]

[0169] In formula (1):

[0170] Represents a multilayer film structure, where:

[0171] A0 represents the bottom A material film in the multilayer film structure;

[0172] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i Thin material

[0173] The upper surface of the membrane is close to A i the lower surface of the material film;

[0174] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0175] B i represents the B material film of the ith combination in the multilayer film structure;

[0176] A i represents the A material film of the ith combination in the multilayer film structure;

[0177] n represents the number of combinations, n=3;

[0178] i represents the combination ordinal number, 1≤i≤n, i is a positive integer;

[0179] M represents a metal periodic array structure.

[0180] In this embodiment, n=3, and from formula (1), the structural design expression of the metal supersurface composite multilayer film is:

[0181]

[0182] In formula (2):

[0183] A0 represents the bottom A material film in the multilayer film structure;

[0184] B1 represents the B material film of the first group in the multilayer film structure;

[0185] A1 represents the A material film of the first group in the multilayer film structure;

[0186] B2 represents the B material film of the second group in the multilayer film structure;

[0187] A2 represents the A material film of the second group in the multilayer film structure;

[0188] B3 represents the B material film of the third group in the multilayer film structure;

[0189] A3 represents the A material film of the third group in the multilayer film structure;

[0190] M represents a metal periodic array structure.

[0191] In this embodiment, the multilayer film structure is a 7-layer structure consisting of a bottom A material film and three combinations, and the metal supersurface composite multilayer film is 8 layers.

[0192] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is circular, and the spacing is 0.08 mm.

[0193] The area of ​​the metal unit is 0.3 mm 2 .

[0194] The metal in the metal periodic array structure is Pt.

[0195] The thickness of the metal periodic array structure is 0.05 μm.

[0196] The material of the A material film in the multi-layer film structure is Ge.

[0197] The material of the B material film in the multi-layer film structure is ZnS.

[0198] The thickness of the Al material film is 0.05 μm.

[0199] The thickness of the A2 material film is 0.04 μm.

[0200] The thickness of the A3 material film is 0.03 μm.

[0201] The thickness of the A material film of the bottom layer is 0.05 μm.

[0202] The thickness of the B1 material film is 0.06 μm.

[0203] The thickness of the B2 material film is 0.05 μm.

[0204] The thickness of the B3 material film is 0.04 μm.

[0205] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0206] Example 4

[0207] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0208] The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure.

[0209] The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is:

[0210]

[0211] In formula (1):

[0212] Represents a multilayer film structure, where:

[0213] A0 represents the bottom A material film in the multilayer film structure;

[0214] (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i The upper surface of the material film is close to A i the lower surface of the material film;

[0215] It represents the continuous multiplication of n combinations, where each combination is close to each other;

[0216] B i represents the B material film of the ith combination in the multilayer film structure;

[0217] A i represents the A material film of the ith combination in the multilayer film structure;

[0218] n represents the number of combinations, n = 1;

[0219] i represents the combination ordinal number, i=1;

[0220] M represents a metal periodic array structure.

[0221] In this embodiment, n=1, and from formula (1), the structural design expression of the metal supersurface composite multilayer film is:

[0222]

[0223] In formula (2):

[0224] A0 represents the bottom A material film in the multilayer film structure;

[0225] B1 represents the B material film of the first group in the multilayer film structure;

[0226] A1 represents the A material film of the first group in the multilayer film structure;

[0227] M represents a metal periodic array structure.

[0228] In this embodiment, the multilayer film structure is a three-layer structure consisting of a bottom A material film and 1 combination, and the metal supersurface composite multilayer film is a four-layer structure.

[0229] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is square, and the spacing is 1.5 mm.

[0230] The area of ​​the metal unit is 0.1 mm 2 .

[0231] The metal in the metal periodic array structure is Ag.

[0232] The thickness of the metal periodic array structure is 0.01 μm.

[0233] The material of the A material film in the multi-layer film structure is Ge.

[0234] The material of the B material film in the multi-layer film structure is SiO2.

[0235] The thickness of the Al material film is 0.01 μm.

[0236] The thickness of the A material film of the bottom layer is 0.01 μm.

[0237] The thickness of the B1 material film is 0.01 μm.

[0238] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0239] Example 5

[0240] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0241] Except for the following technical parameters, the rest of this embodiment is the same as that of Embodiment 4.

[0242] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is circular, and the spacing is 2 mm.

[0243] The area of ​​the metal unit is 2mm 2 .

[0244] The metal in the metal periodic array structure is Ti.

[0245] The thickness of the metal periodic array structure is 0.5 μm.

[0246] The material of the A material film in the multi-layer film structure is Si.

[0247] The material of the B material film in the multi-layer film structure is SiO2.

[0248] The thickness of the Al material film is 0.3 μm.

[0249] The thickness of the A material film of the bottom layer is 0.3 μm.

[0250] The thickness of the B1 material film is 0.4 μm.

[0251] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0252] Example 6

[0253] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0254] Except for the following technical parameters, the rest of this embodiment is the same as that of Embodiment 2.

[0255] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is hexagonal, and the spacing is 2.5 mm.

[0256] The area of ​​the metal unit is 3mm 2 .

[0257] The metal in the metal periodic array structure is Mo.

[0258] The thickness of the metal periodic array structure is 1 μm.

[0259] The material of the A material film in the multi-layer film structure is Si.

[0260] The material of the B material film in the multi-layer film structure is ZnS.

[0261] The thickness of the Al material film is 0.5 μm.

[0262] The thickness of the A2 material film is 0.4 μm.

[0263] The thickness of the A material film of the bottom layer is 0.5 μm.

[0264] The thickness of the B1 material film is 0.6 μm.

[0265] The thickness of the B2 material film is 0.5 μm.

[0266] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0267] Example 7

[0268] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0269] Except for the following technical parameters, the rest of this embodiment is the same as that of Embodiment 3.

[0270] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is ring-shaped, and the spacing is 3 mm.

[0271] The area of ​​the metal unit is 8mm 2 .

[0272] The metal in the metal periodic array structure is Au.

[0273] The thickness of the metal periodic array structure is 1.5 μm.

[0274] The material of the A material film in the multi-layer film structure is Ge.

[0275] The material of the B material film in the multi-layer film structure is SiO2.

[0276] The thickness of the Al material film is 0.8 μm.

[0277] The thickness of the A2 material film is 0.7 μm.

[0278] The thickness of the A3 material film is 0.6 μm.

[0279] The thickness of the A material film of the bottom layer is 0.8 μm.

[0280] The thickness of the B1 material film is 0.7 μm.

[0281] The thickness of the B2 material film is 0.6 μm.

[0282] The thickness of the B3 material film is 0.5 μm.

[0283] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0284] Example 8

[0285] A metal super-surface composite multilayer film compatible with high microwave transmittance effect.

[0286] Except for the following technical parameters, the rest of this embodiment is the same as that of Embodiment 1.

[0287] The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing. The shape of the metal units is octagonal, and the spacing is 5 mm.

[0288] The area of ​​the metal unit is 10 mm 2 .

[0289] The metal in the metal periodic array structure is Ti.

[0290] The thickness of the metal periodic array structure is 2 μm.

[0291] The material of the A material film in the multi-layer film structure is Si.

[0292] The material of the B material film in the multi-layer film structure is ZnO.

[0293] The thickness of the Al material film is 1 μm.

[0294] The thickness of the A2 material film is 1 μm.

[0295] The thickness of the A3 material film is 1 μm.

[0296] The thickness of the A4 material film is 1 μm.

[0297] The thickness of the A material film of the bottom layer is 1 μm.

[0298] The thickness of the B1 material film is 1 μm.

[0299] The thickness of the B2 material film is 1 μm.

[0300] The thickness of the B3 material film is 1 μm.

[0301] The thickness of the B4 material film is 1 μm.

[0302] The infrared reflectivity of this embodiment in the 3-5 μm and 8-14 μm bands is greater than 85%, and it is compatible with a high transmittance of greater than 95% for 2-18 GHz microwaves.

[0303] Due to the adoption of the above technical solution, this specific implementation has the following positive effects compared with the prior art:

[0304] 1. This specific implementation method aims to solve the problem that existing non-metallic multilayer film materials need to have large thickness and high number of layers to achieve high infrared reflectivity. Metal materials with stable high infrared reflectivity are introduced as upper layer materials. When electromagnetic waves are incident on the upper metal material containing a large number of free electrons, the changing magnetic field will generate an electric field, which will cause the vibration of free electrons to generate infrared radiation and achieve high infrared reflectivity. The simulation results show that when the thickness of the upper metal periodic array structure is 0.1μm, the infrared reflectivity of the overall structure can be greatly increased to more than 85% and the effect is stable. Therefore, the infrared reflectivity and stability of the metal super-surface composite multilayer film compatible with microwave high transmittance can be significantly improved.

[0305] 2. In order to address the shortcoming of metal materials in the prior art that they can cause high microwave reflection, this specific embodiment adopts a metal periodic array structure, that is, there are sub-wavelength intervals of microwaves between adjacent metal units. This sub-wavelength interval increases the transmittance of microwaves, that is, due to the coupling effect between surface plasmons and light, light can pass through these sub-wavelength gaps with a higher transmittance, thus overcoming the high reflection shortcoming of existing metal materials in the microwave field and significantly improving the microwave transmission and infrared reflection effects of the metal super-surface composite multilayer film that is compatible with high microwave transmission effects.

[0306] 3. In this specific implementation, since the upper metal periodic array structure can achieve high infrared reflection effect, the material selection of the lower multilayer film structure can choose low-cost common materials, and is no longer limited to precious and scarce materials such as Si, SiO2, ZnO and ZnS. These materials have good mechanical properties and temperature resistance. Therefore, they can not only significantly improve the mechanical properties and temperature resistance of the metal supersurface composite multilayer film compatible with microwave high transmittance effect, but also have a wider range of material selection.

[0307] 4. This specific implementation is shown in the accompanying drawings. Figure 1is a schematic structural diagram of a metal super-surface composite multilayer film having a high microwave transmittance effect according to Example 1, Figure 2 for Figure 1 The infrared reflectivity simulation comparison diagram of the metal super surface composite multilayer film and its underlying multilayer film structure is shown; Figure 3 for Figure 1 The microwave transmittance simulation effect of the metal super surface composite multilayer film is shown in Figure 2. Figure 1 It can be seen that the multilayer film structure is a 9-layer structure composed of a bottom A material film and 4 combinations, the metal super surface composite multilayer film is 10 layers, and the upper layer is a metal periodic array structure; the layer thickness of the metal periodic array structure is 0.1μm, the multilayer film structure is 2.966μm, the bottom A material film thickness is 0.054μm, and the thickness of the metal super surface composite multilayer film compatible with microwave high transmittance effect is 3.066μm, so this specific implementation has a small number of layers and a thin thickness, which simplifies the process. Figure 2 It can be seen that the superimposed upper metal periodic array structure has a very significant effect on improving the infrared reflectivity, reaching an infrared reflectivity of more than 85% in the 3-5μm and 8-14μm bands. Figure 3 It can be seen that the metal super-surface composite multilayer film compatible with microwave high transmittance effect not only has the advantage of high infrared reflection, but also has a high transmittance effect of more than 95% for 2-18GHz microwaves, that is, it is compatible with microwave high transmittance effect.

[0308] Therefore, this specific implementation has the characteristics of few layers, thin thickness, simple process, high infrared reflectivity, stable infrared reflectivity, wide material selection and compatibility with high microwave transmittance effect.

Claims

1. A metal super-surface composite multilayer film compatible with microwave high transmittance effect, characterized in that: The metal super-surface composite multilayer film compatible with microwave high transmittance effect is composed of an upper layer and a lower layer; the upper layer is a metal periodic array structure, and the lower layer is a multilayer film structure; The structural design expression of the metal supersurface composite multilayer film compatible with microwave high transmittance effect is: In formula (1): Represents a multilayer film structure, where: A0 represents the bottom A material film in the multilayer film structure; (B i A i ) indicates that B i Material film and A i The i-th combination of material films, in which B i The upper surface of the material film is close to A i the lower surface of the material film; It represents the continuous multiplication of n combinations, where each combination is close to each other; B i represents the B material film of the ith combination in the multilayer film structure; A i represents the A material film of the ith combination in the multilayer film structure; n represents the number of combinations, 1≤n≤4, n is a positive integer; i represents the combination ordinal number, 1≤i≤n, i is a positive integer; M represents a metal periodic array structure; The metal periodic array structure is a grid array in which the same metal units are arranged in rows and columns with equal spacing; the shape of the metal units is one of a circle, a polygon and a ring, and the spacing is 0.05 to 5 mm.

2. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The area of ​​the metal unit is 0.1 to 10 mm 2 .

3. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The metal in the metal periodic array structure is one of Au, Cu, Pt, Ag, Ti and Mo.

4. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The thickness of the metal periodic array structure is 0.01-2 μm.

5. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The material of the A material film in the multi-layer film structure is one of Ge and Si.

6. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The material of the B material film in the multi-layer film structure is one of SiO2, ZnO and ZnS.

7. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The A i The thickness of the material film is 0.01 to 1 μm.

8. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: The thickness of the A material film of the bottom layer is 0.01-1 μm.

9. The metal super-surface composite multilayer film compatible with microwave high transmittance effect according to claim 1, characterized in that: B i The thickness of the material film is 0.01 to 1 μm.

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