Multilayer film infrared stealth device based on germanium-selenium material

Abstract

The invention discloses a multilayer film infrared stealth device based on a germanium-selenium material. The multilayer film infrared stealth device sequentially comprises a substrate, a reflecting layer, a dielectric layer, a functional layer and a protective layer from bottom to top, the functional layer is germanium selenium, the chemical formula of the functional layer is GexSe100-x, x is greater than or equal to 20 and less than or equal to 70, and the thickness of the functional layer ranges from 10 nm to 400 nm; the emissivity of the device in the infrared band of 8-14 microns is smaller than or equal to 0.2, and invisibility can be achieved in the infrared band. Germanium-selenium has excellent thermal stability and can keep stable performance under complex environmental conditions, and emissivity in a specific frequency range is realized by designing a simple multilayer film structure and controlling parameters such as material and thickness of each layer.

Description

Technical Field

[0001] The present invention relates to the technical fields of phase change materials and optical devices, and particularly relates to a multi-layer film infrared stealth device based on germanium selenide materials. Background Art

[0002] The main bands of infrared detection are mid-wave infrared (3 - 5 μm) and long-wave infrared (8 - 14 μm). Since in the range of 8 - 14 μm, infrared signals can penetrate the atmosphere better, enabling long-distance detection. Long-wave infrared detectors can reach 1.5 - 2 times the distance of mid-wave infrared detectors, having unique advantages in infrared detection and being the key working band of various infrared detection systems. In the long-wave infrared band (8 - 14 μm), infrared signals mainly originate from the thermal radiation of the target object, and the signal intensity in this band is closely related to the target temperature and surface emissivity. The main methods of infrared stealth are divided into two categories: controlling temperature and controlling emissivity. The former mainly achieves this by reducing the surface temperature of the target, but this often requires a complex cooling system and has many limitations in practical applications. The latter uses infrared low-emissivity materials to weaken or eliminate the difference in reflected and radiated energy between the target itself and the background environment, blend the infrared target of itself into the background, reduce the recognition of the target, and achieve the effect of confusing detection.

[0003] Existing devices mainly control emissivity by using colorants with low infrared emissivity or incorporating fillers with low infrared emissivity into colored coatings to reduce infrared emissivity. However, the number of existing colorants is very limited, and the physical and mechanical properties and adhesion of the coatings are relatively low, making it difficult to withstand long-term ultraviolet irradiation and atmospheric corrosion. Recent research has proposed an infrared stealth device based on chalcogenide phase change materials, which has the advantages of wide-band low emissivity and phase structure transformation to regulate the emissivity band in the infrared band, and has received extensive attention in the field of infrared stealth materials. However, the crystallization temperature of traditional germanium antimony telluride materials is 150 °C, and crystallization will occur at high temperatures, resulting in a significant change in infrared emissivity and being difficult to maintain a stable state under severe working conditions (such as the surface temperature of an aero-engine usually exceeds 300 °C). Therefore, it is urgent to develop an infrared stealth phase change material with ultra-low emissivity in the long-wave infrared band and high thermal stability of the amorphous phase. Summary of the Invention

[0004] In order to overcome the above defects existing in the prior art, the present invention provides a multi-layer film infrared stealth device based on germanium selenide materials. Germanium selenide has excellent thermal stability and can maintain stable performance under complex environmental conditions. By designing a simple multi-layer film structure and controlling parameters such as the material and thickness of each layer, the emissivity within a specific frequency range can be achieved.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A multilayer infrared stealth device based on germanium selenide material, which successively includes a substrate, a reflective layer, an adhesion layer, a dielectric layer, a functional layer, and a protective layer from bottom to top; the functional layer is germanium selenide with the chemical formula Ge x Se 100-x , where 20 ≤ x ≤ 70, and the thickness range is 10 nm - 400 nm; the emissivity of the device in the 8 - 14 μm infrared band is ≤ 0.2, and it can achieve stealth in the infrared band.

[0007] The adhesion layer is used to enhance the adhesion between the thin film and the substrate; the reflective layer is used to provide specular reflection; the dielectric is used to regulate the reflectivity of the device; the functional layer is used to regulate the reflectivity of the device; the protective layer is located above the functional layer to prevent oxidation or surface damage. The adhesion layer is Cr, Al, and the reflective layer is a thin film with a reflectivity ≥ 90%, including but not limited to Pt, Au, etc.; the dielectric layer is ITO; the protective layer is any one of ITO and SiO2.

[0008] The thickness of the adhesion layer is 3 - 10 nm; the thickness of the reflective layer ≥ 50 nm; the thickness of the dielectric layer is 20 - 200 nm; the thickness of the functional layer is 20 - 300 nm; the thickness of the protective layer is 20 - 200 nm.

[0009] The reflective layer, dielectric layer, functional layer, and protective layer are prepared by one - time stacking, and the preparation methods include but are not limited to magnetron sputtering, chemical vapor deposition, atomic deposition, or electron beam evaporation.

[0010] The crystallization temperature of the functional layer germanium selenide can reach ≥ 350 °C, and it can maintain stable performance under harsh working condition temperatures.

[0011] The emissivity is adjusted by adjusting the phase structure of the functional layer, and the peak of the emissivity undergoes a red - shift with the crystallization of the functional layer;

[0012] When the thickness of the dielectric layer is 150 nm, the thickness of the functional layer is 300 nm and it is in the amorphous phase, the emissivity of the device in the 8 - 14 μm infrared band is ≤ 0.2, and at this time, the peak of the emissivity appears at 3 - 5 μm; when the functional layer thin film of the device is crystallized by external excitation drive, the device still maintains a similar ultra - low emissivity in the 8 - 14 μm infrared band as before crystallization, but at this time, the peak of the emissivity appears in the non - atmospheric window band (5 - 8 μm), which is used to simultaneously achieve heat dissipation in the non - atmospheric window band and stealth in the infrared band, so it can simultaneously achieve heat dissipation and stealth in the infrared detection band.

[0013] The phase structure adjustment of the functional layer is achieved by external excitation drive, and the external excitation includes but is not limited to laser pulses, electrical pulses, or heating.

[0014] The emissivity of the device can be adjusted by adjusting the thicknesses of the dielectric layer and the functional layer, and the peak position of the emissivity undergoes a red shift with the increase in the thicknesses of the dielectric layer and the functional layer.

[0015] Advantages of the present invention:

[0016] The infrared stealth device based on germanium selenide material proposed by the present invention has an ultra-low emissivity in the long-wave infrared band (8 - 14 μm), and thus has a good infrared stealth effect; the crystallization temperature of the germanium selenide material is ≥350 °C, having excellent thermal stability and being able to maintain stable low-emission performance under severe working condition temperatures.

[0017] The infrared stealth device based on germanium selenide material proposed by the present invention can achieve emissivity tuning of the device in the infrared band through the switching between the amorphous phase and the crystalline phase of the functional layer, as well as the thickness control of the dielectric layer and the functional layer, thereby simultaneously realizing heat dissipation in the non-atmospheric window band and the stealth effect in the infrared band, enabling the detected object to dissipate heat synchronously and be stealthy in the infrared detection band.

[0018] The preparation process of the infrared stealth device based on germanium selenide material proposed by the present invention can be prepared by one-time stacking. The bonding force between the multi-layers is strong, and the adhesion to the substrate is good, effectively suppressing the peeling phenomenon and ensuring the durability of the device in a complex environment. Description of the drawings

[0019] Figure 1 It is a schematic structural diagram of an infrared stealth multi-layer film device based on germanium selenide material.

[0020] Figure 2 It is an emissivity spectrogram of the multi-layer film device proposed by the present invention in the range of 8 - 14 μm.

[0021] Figure 3 It is a schematic diagram of the effect of the device sample under visible light.

[0022] Figure 4 It is a schematic diagram of the effect of the device sample under an infrared camera. Detailed implementation manners

[0023] The present invention will be further described in detail below with reference to the drawings.

[0024] Figure 1 It is a structural diagram of an infrared stealth multi-layer film device based on germanium selenide material. The thickness of the adhesion layer 102 is 5 nm; the thickness of the reflection layer 103 is above 100 nm; the thickness of the dielectric layer 104 is 20 - 200 nm; the thickness of the functional layer 105 is 20 - 300 nm; the thickness of the protection layer 106 is 20 nm.

[0025] The adhesion layer is used to enhance the adhesion between the thin film and the substrate; the reflective layer 103 is used for specular reflection. The dielectric layer 104 is used to adjust the reflectivity of the device. The functional layer 105 is made of germanium selenide material and can be used to adjust the reflectivity of the device. The protective layer 106 is used to prevent oxidation or damage of the functional layer, etc.

[0026] Figure 2 This is the emissivity spectrogram of the multi-layer film device proposed by the present invention in the 8-14 μm band. Based on Figure 1 For the multi-layer film device described above, the substrate 101 is selected as Si material, the adhesion layer 102 is made of Cr with a thickness of 5 nm, the reflective layer 103 is made of Pt with a thickness of 100 nm, the dielectric layer 104 is made of ITO with a thickness of 50 nm, the functional layer 105 is made of GeSe thin film with a thickness of 60 nm, and the protective layer 106 is made of ITO with a thickness of 20 nm. The emissivity of the device in the 8-14 μm range is close to 0.

[0027] Figure 3 This is a schematic diagram of the effect of the sample under visible light. The star-shaped area in the figure is the multi-layer film device, and the rest is the background area. Under visible light, the device has an obvious contrast with the background area at 300 °C.

[0028] Figure 4 This is a schematic diagram of the effect of the sample under an infrared camera. Under a long-wave infrared (8-14 μm) camera, the contrast between the device and the background at 300 °C is extremely small and difficult to distinguish, indicating that the multi-layer film device has excellent stealth performance in the long-wave infrared band, can effectively reduce the thermal radiation difference between the high-temperature target and the background, and thus achieve the effect of infrared stealth. This stealth effect is not only applicable to static targets but can also be extended to dynamic environments, providing a reliable solution for stealth applications in complex scenarios.

[0029] The following further illustrates the present invention with specific embodiments as examples.

[0030] Embodiment 1

[0031] This embodiment is a multi-layer film infrared stealth device based on germanium selenide material, and the specific process is as follows:

[0032] A multi-layer film infrared stealth device made of germanium selenide material was prepared using a magnetron sputtering device. As Figure 1 shown, the adhesion layer 102 is made of Cr with a thickness of 5 nm, the reflective layer 103 selects Pt material with a thickness of 100 nm, the dielectric layer 104 selects ITO with a thickness of 50 nm, the functional layer 105 selects GeSe material with a thickness of 60 nm, and the protective layer 106 selects ITO with a thickness of 20 nm.

[0033] The emissivity of the infrared stealth device based on germanium selenide material was measured using a time-resolved infrared spectrometer, and the results are asFigure 2 As shown, the emissivity of the device in the 8 - 14μm band is extremely low, approaching 0.

[0034] The infrared stealth device based on germanium selenide material has the following effect under visible light Figure 3 As shown, under visible light, when the sample is heated to 300°C, the sample can be distinguished from the normal background by the naked eye.

[0035] The infrared stealth device based on germanium selenide material has the following effect under an infrared camera Figure 4 As shown, under a long - wave infrared (8 - 14μm) camera, the contrast between the sample at 300°C and the background is small, and it can hardly be distinguished by the infrared camera. This phenomenon indicates that this multilayer film device has excellent stealth performance in the long - wave infrared band, can effectively reduce the thermal radiation difference between the high - temperature target and the background, so as to achieve the effect of infrared stealth.

[0036] Implementation Case 2

[0037] This implementation case is a multilayer film infrared stealth device based on germanium selenide material, and the specific process is as follows:

[0038] The multilayer film infrared stealth device based on germanium selenide material is a layered structure, prepared by magnetron sputtering. As Figure 1 shown, the specific design is as follows: The adhesion layer 102 uses Al with a thickness of 7nm, the reflection layer 103 selects Pt material with a thickness of 100nm, the dielectric layer 104 selects ITO with a thickness of 150nm, the functional layer 105 selects GeSe material with a thickness of 300nm, and the protective layer 106 selects ITO with a thickness of 20nm.

[0039] The emissivity of the infrared stealth device based on germanium selenide material is measured by a time - resolved infrared spectrometer. When the GeSe material of the functional layer 104 is in the amorphous phase, the device has an ultra - low emissivity in the long - wave infrared band (8 - 14μm); when the GeSe material of the device functional layer 104 is transformed into the crystalline phase by heating and annealing, the device not only maintains an ultra - low emissivity in the long - wave infrared band (8 - 14μm), but also has a relatively high emissivity in the non - atmospheric window (5 - 8μm). This non - atmospheric window can be used for heat dissipation, thus realizing both the heat dissipation of the detected object and the stealth effect in the infrared detection band.

Claims

1. A multi-layer film infrared stealth device based on germanium selenide material, characterized in that, From bottom to top, there are a substrate (101), an adhesion layer (102), a reflective layer (103), a dielectric layer (104), a functional layer (105), and a protective layer (106) in sequence; the functional layer (105) is germanium selenide with the chemical formula Ge x Se 100-x , where 0 ≤ x ≤ 70 and the thickness range is 10 nm - 400 nm; the emissivity of the device in the 8 - 14 μm infrared band is ≤ 0.2 to achieve stealth.

2. The multi-layer film infrared stealth device based on germanium selenide material according to claim 1, wherein The adhesion layer (102) is used to enhance the adhesion between the thin film and the substrate; the reflective layer (103) is used to provide specular reflection; the dielectric layer (104) is used to regulate the reflectivity of the device; the functional layer (105) is used to regulate the reflectivity of the device; the protective layer (106) is located above the functional layer to prevent oxidation or surface damage.

3. The multi-layer film infrared stealth device based on germanium selenide material according to claim 1, characterized in that, The adhesion layer (102) is Cr, Al; the reflective layer (103) is a thin film with a reflectivity ≥ 90%, including but not limited to Pt, Au; the dielectric layer (104) is ITO; the protective layer (106) is any one of ITO, SiO2.

4. A multilayer film infrared stealth device based on germanium selenide material according to claim 1, characterized in that The thickness of the adhesion layer (102) is 3 - 10 nm; the thickness of the reflective layer (103) ≥ 50 nm; the thickness of the dielectric layer (104) is 20 - 200 nm; the thickness of the functional layer (105) is 20 - 300 nm; the thickness of the protective layer (106) is 20 - 200 nm.

5. The multi-layer film infrared stealth device based on germanium selenide material according to claim 1, characterized in that, The adhesion layer (102), reflective layer (103), dielectric layer (104), functional layer (105) and protective layer (106) are prepared by one-time stacking.

6. The multilayer film infrared stealth device based on germanium selenide material according to claim 1, wherein The crystallization temperature of germanium selenide in the functional layer (105) reaches ≥ 350 °C, and it can maintain stable performance under harsh working condition temperatures.

7. A multilayer film infrared stealth device based on germanium selenide material according to claim 1, characterized in that, The emissivity of the device is adjusted by adjusting the phase structure of the functional layer (105), and the peak of the emissivity redshifts with the crystallization of the functional layer (105); When the thickness of the dielectric layer (104) is 150 nm, the thickness of the functional layer (105) is 300 nm and it is in the amorphous phase, the emissivity of the device in the 8 - 14 μm infrared band ≤ 0.2, and at this time the peak of the emissivity appears at 3 - 5 μm; when the functional layer thin film of the device is crystallized by external excitation drive, the device still maintains a near - ultra - low emissivity in the 8 - 14 μm infrared band similar to that before crystallization, but at this time the peak of the emissivity appears in the non - atmospheric window band of 5 - 8 μm, which is used to simultaneously achieve heat dissipation in the non - atmospheric window band and stealth in the infrared band, synchronously realizing heat dissipation and stealth in the infrared band.

8. The multi-layer film infrared stealth device based on germanium selenide material according to claim 1, characterized in that, The phase structure adjustment of the functional layer (105) is achieved by external excitation drive, and the external excitation is one of laser pulse, electrical pulse or heating.

9. The multi-layer film infrared stealth device based on germanium selenide material according to claim 1, wherein, The emissivity is adjusted by adjusting the thicknesses of the dielectric layer (104) and the functional layer (105), and the peak position of the emissivity redshifts with the increase in the thicknesses of the dielectric layer (104) and the functional layer (105).

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