Black film and preparation method and application thereof

Abstract

The invention provides a black film as well as a preparation method and application thereof. The black film comprises at least two laminated film layers which are laminated, the laminated film layer comprises an absorption film and a dielectric film which are laminated; a dielectric film is arranged at the top of the black film, and at least one layer of water-blocking film is arranged between the absorbing film and the dielectric film in the laminated film layer at the top of the black film. According to the invention, at least one layer of water-blocking film is arranged between the absorbing film and the dielectric film in the laminated film layer (the laminated film layer in which light enters and is exposed in the external environment) at the top of the black film, so that corrosion of water vapor to the absorbing film in the laminated film layer at the top of the black film is prevented, and the water vapor corrosion resistance of the black film is enhanced; water failure of the black film in an environment with relatively high humidity is avoided; the black film provided by the invention passes a double-85 environment test and has a wider application range.

Description

Technical Field

[0001] The invention belongs to the technical field of thin films and relates to a black film, in particular to a black film and a preparation method and application thereof. Background Art

[0002] Black film is a thin film material with high light absorption and low reflectivity, which is widely used in the fields of optics, electronics and energy. In optical devices, black film is used to reduce stray light and improve imaging quality; in solar cells, it can enhance light absorption and improve energy conversion efficiency.

[0003] However, the black film disclosed in the prior art has poor stability, is prone to water failure in an environment with high humidity, and is difficult to pass the double 85 environmental test, thereby limiting the scope of use of the black film.

[0004] CN112526663A discloses an absorption film based on atomic layer deposition, which is composed of a substrate and a multilayer absorption film system thereon, wherein the multilayer absorption film system is composed of an absorption film layer and a dielectric film layer alternately, wherein the absorption film layer is the innermost layer and is arranged close to the substrate; the dielectric film layer is the outermost layer; and the multilayer absorption film system is obtained by an atomic layer deposition method. The absorption film prepared by the atomic layer deposition technology in the document has an absorption rate of more than 99% within the designed band, and can have important applications in special fields such as complex optical surfaces with high aspect ratios and optical elements with large curvature, and is expected to be widely used in virtual reality, anti-counterfeiting and other fields. However, the absorption film based on atomic layer deposition is prone to water failure and lacks stability.

[0005] CN103017384A discloses a carbon film-assisted solar selective absorption film system and a preparation method thereof. The carbon film-assisted solar selective absorption film system includes a titanium oxynitride film, an amorphous carbon film, a silicon nitride film, and a silicon dioxide film coated on a metal substrate. The document introduces an amorphous carbon film to make the solar absorption rate of the absorption film system as high as 98.0%, and the emissivity can be as low as 2.3%, with extremely high photothermal conversion efficiency and heat collection efficiency. Similarly, the carbon film-assisted solar selective absorption film system is prone to failure in an environment with high humidity, which limits its scope of use.

[0006] The black films disclosed in the prior art have certain defects, such as being prone to water failure in an environment with high humidity and being difficult to pass the double 85 environmental test, thus limiting the scope of use of the black films. Therefore, it is very important to develop and design a new type of black film and its preparation method. Summary of the invention

[0007] In view of the deficiencies in the prior art, the object of the present invention is to provide a black film and a preparation method and application thereof. In the present invention, at least one water-blocking film is provided between the absorbing film and the dielectric film in the stacked film layer (the stacked film layer into which light is incident and exposed to the external environment) on the top of the black film, thereby preventing water vapor from corroding the absorbing film in the stacked film layer on the top of the black film, thereby enhancing the water vapor corrosion resistance of the black film and avoiding water failure of the black film in an environment with high humidity; the black film provided by the present invention has passed the double 85 environmental test and has a wider range of applications.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a black film, the black film comprising at least two stacked film layers; the stacked film layers comprising an absorption film and a dielectric film stacked;

[0010] The top of the black film is a dielectric film, and at least one layer of water-blocking film is arranged between the absorption film and the dielectric film in the stacked film layers on the top of the black film.

[0011] The materials used as the absorption film in the prior art are often easily ineffective under water vapor erosion, thereby causing the performance of the black film to fail.

[0012] In the present invention, at least one water-blocking film is provided between the absorbing film and the dielectric film in the stacked film layer (the stacked film layer into which light is incident and exposed to the external environment) on the top of the black film, thereby preventing water vapor from corroding the absorbing film in the stacked film layer on the top of the black film, thereby enhancing the water vapor corrosion resistance of the black film and avoiding water failure of the black film in an environment with high humidity; the black film provided by the present invention has passed the double 85 environmental test and has a wider range of applications.

[0013] Since a dielectric film with a lower refractive index needs to be used on the top of the black film, and the absorption film in the stacked film layer on the top of the black film needs to avoid erosion by water vapor; therefore, the water-blocking film can only be set between the dielectric film and the absorption film on the top of the black film, which not only enhances the water resistance of the black film, but also avoids affecting the light absorption performance of the black film.

[0014] Preferably, the refractive index of the absorption film in each layer of the stacked film is higher than that of the dielectric film.

[0015] Based on the principle of optical design, the provided black film includes at least two stacked film layers, each of which is stacked with a dielectric film with a lower refractive index and an absorption film with a higher refractive index, and the absorption film is located on the side where light is incident, thereby reducing the reflection of light by the black film and improving the light absorption performance of the black film.

[0016] Preferably, the refractive index of the absorption film in each layer of the stacked film is independently 2 to 2.5, and the absorption coefficient is independently not less than 1.

[0017] The absorption film in each layer of the stacked film in the present invention also has a relatively high light absorption coefficient, which also enables the black film to have better light absorption performance, thereby further improving the performance of the black film.

[0018] In the present invention, the refractive index of the absorption film in each layer of the stacked film layer is independently 2 to 2.5, for example, it can be 2, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45 or 2.5, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] Preferably, the refractive index of the dielectric film in each layer of the stacked film is independently 1.35 to 1.7, for example, it can be 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.68, 1.69, 1.695, 1.7 or 1.7, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] The light absorption coefficient of the dielectric film in each layer of the stacked film in the present invention is not limited, and is preferably a dielectric film with light absorption performance.

[0021] The refractive index of the dielectric film in each layer of the stacked film layer in the present invention is independently 1.35-1.7, for example, it can be 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, 1.50, 1.51, 1.52, 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, 1.59, 1.60, 1.61, 1.62, 1.63, 1.64, 1.65, 1.66, 1.67, 1.68, 1.69 or 1.70, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Preferably, the thickness of the absorption film in each layer of the stacked film is independently 15 to 200 nm, for example, it can be 15 nm, 20 nm, 40 nm, 60 nm, 80 nm, 100 nm, 120 nm, 140 nm, 160 nm, 180 nm or 200 nm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0023] Preferably, the material of the absorption film in each layer of the stacked film layer independently includes any one of TiAlC, TiN or TiAlN, or a combination of at least two of them. Typical but non-limiting combinations include a combination of TiAlC and TiN, a combination of TiN and TiAlN, a combination of TiAlC and TiAlN, or a combination of TiAlC, TiN and TiAlN, preferably TiAlC.

[0024] Preferably, the thickness of the dielectric film in each layer of the stacked film layer is independently 30 to 100 nm, for example, it can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm or 100 nm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0025] Preferably, the material of the dielectric film in each layer of the stacked film layer independently includes any one of SiO2, MgF or Al2O3 or a combination of at least two of them. Typical but non-limiting combinations include a combination of SiO2 and MgF, a combination of MgF and Al2O3, a combination of SiO2 and Al2O3, or a combination of SiO2, MgF and Al2O3, preferably SiO2.

[0026] In the present invention, the material of the absorption film is preferably TiAlC, and the material of the dielectric film is preferably SiO2. The TiAlC absorption film can serve as a good absorption layer, which can absorb light in a specific wavelength range. In combination with the SiO2 dielectric film, it can achieve efficient absorption of a wide wavelength range from visible light to near-infrared light. In addition, in solar cells, the TiAlC absorption film can effectively absorb light energy, and the SiO2 dielectric film can optimize the transmission and reflection of light. The synergistic effect of the two can improve the conversion efficiency of light energy to electrical energy.

[0027] Preferably, the thickness of the water-blocking film is 5 to 20 nm, for example, 5 nm, 7 nm, 9 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm or 20 nm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] Preferably, the material of the water-blocking film includes any one of Al2O3, ZrO2 or TiO2, or a combination of at least two of them. Typical but non-limiting combinations include a combination of Al2O3 and ZrO2, a combination of ZrO2 and TiO2, a combination of Al2O3 and TiO2, or a combination of Al2O3, ZrO2 and TiO2, preferably Al2O3.

[0029] In a second aspect, the present invention provides a method for preparing the black film according to the first aspect, the preparation method comprising:

[0030] On the surface of the substrate, an absorption film and a dielectric film are repeatedly deposited in sequence by atomic layer deposition;

[0031] When the absorption film is deposited for the last time, at least one layer of water-blocking film is first deposited on the surface of the obtained absorption film by atomic layer deposition, and then the dielectric film is deposited.

[0032] Preferably, the temperature when the absorption film, the dielectric film and the water-blocking film are deposited by atomic layer deposition is independently 350-500°C, for example, it can be 350°C, 355°C, 360°C, 365°C, 370°C, 375°C, 380°C, 385°C, 390°C, 395°C, 400°C, 405°C, 410°C, 415°C, 420°C, 425°C, 430°C, 435°C, 440°C, 445°C, 450°C, 455°C, 460°C, 465°C, 470°C, 475°C, 480°C, 485°C, 490°C, 495°C or 500°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0033] Preferably, when the material of the absorption film is TiAlC, when the absorption film is deposited by atomic layer deposition, the precursors used include Al(CH3)3 and TiCl4.

[0034] Preferably, when the material of the dielectric film is SiO2, when the dielectric film is deposited by atomic layer deposition, the precursors used include diisopropylaminosilane and O3.

[0035] Preferably, when the material of the water-blocking film is Al2O3, when the water-blocking film is deposited by atomic layer deposition, the precursors used include Al(CH3)3 and O3.

[0036] In a third aspect, the present invention provides an application of the black film described in the first aspect, wherein the black film is used in the fields of optics, electronics or energy.

[0037] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] In the present invention, at least one water-blocking film is provided between the absorbing film and the dielectric film in the stacked film layer (the stacked film layer into which light is incident and exposed to the external environment) on the top of the black film, thereby preventing water vapor from corroding the absorbing film in the stacked film layer on the top of the black film, thereby enhancing the water vapor corrosion resistance of the black film and avoiding water failure of the black film in an environment with high humidity; the black film provided by the present invention has passed the double 85 environmental test and has a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a curve showing the change of reflectivity of the black film with wavelength in the initial state, after 600h of double 85 test and after 1000h of double 85 test.

[0041] Figure 2 Schematic diagram of the structure of the black film on the substrate in Example 1.

[0042] Among them, 1-first stacked film layer; 2-second stacked film layer; 3-third stacked film layer; 4-fourth stacked film layer; 5-first TiAlC absorption film; 6-first SiO2 dielectric film; 7-second TiAlC absorption film; 8-second SiO2 dielectric film; 9-third TiAlC absorption film; 10-third SiO2 dielectric film; 11-fourth TiAlC absorption film; 12-fourth SiO2 dielectric film; 13-Al2O3 water-blocking film. DETAILED DESCRIPTION

[0043] It should be understood that, in the description of the present invention, the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0044] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0045] Example 1

[0046] This embodiment provides a Figure 2The black film shown includes a first laminated film layer 1, a second laminated film layer 2, a third laminated film layer 3, and a fourth laminated film layer 4 (light enters the black film from a surface of the fourth laminated film layer 4 away from the third laminated film layer 3);

[0047] The first stacked film layer 1 includes a first TiAlC absorption film 5 with a thickness of 130 nm and a first SiO2 dielectric film 6 with a thickness of 21 nm.

[0048] The second stacked film layer 2 includes a second TiAlC absorption film 7 with a thickness of 130 nm and a second SiO2 dielectric film 8 with a thickness of 21 nm.

[0049] The third stacked film layer 3 includes a third TiAlC absorption film 9 with a thickness of 130 nm and a third SiO2 dielectric film 10 with a thickness of 21 nm.

[0050] The fourth stacked film layer 4 includes a fourth TiAlC absorption film 11 with a thickness of 130 nm and a fourth SiO2 dielectric film 12 with a thickness of 21 nm.

[0051] The refractive index of the first TiAlC absorption film 5, the second TiAlC absorption film 7, the third TiAlC absorption film 9, and the fourth TiAlC absorption film 11 is 2.3, and the absorption coefficient is 1.3;

[0052] The refractive index of the first SiO2 dielectric film 6, the second SiO2 dielectric film 8, the third SiO2 dielectric film 10, and the fourth SiO2 dielectric film 12 is 1.46;

[0053] The bottom of the black film is the first TiAlC absorption film 5, and the top is the fourth SiO2 dielectric film 12. A 10nm thick Al2O3 water-blocking film 13 is arranged between the fourth TiAlC absorption film 11 and the fourth SiO2 dielectric film 12 in the stacked film layers on the top of the black film.

[0054] The preparation method of the black film comprises:

[0055] On the surface of the substrate, atomic layer deposition is sequentially performed to obtain a first TiAlC absorption film 5, a first SiO2 dielectric film 6, a second TiAlC absorption film 7, a second SiO2 dielectric film 8, a third TiAlC absorption film 9, a third SiO2 dielectric film 10, a fourth TiAlC absorption film 11, an Al2O3 water-blocking film 13 and a fourth SiO2 dielectric film 12;

[0056] The temperature during the atomic layer deposition of the first TiAlC absorption film 5, the first SiO2 dielectric film 6, the second TiAlC absorption film 7, the second SiO2 dielectric film 8, the third TiAlC absorption film 9, the third SiO2 dielectric film 10, the fourth TiAlC absorption film, the Al2O3 water-blocking film 13 and the fourth SiO2 dielectric film is 400°C;

[0057] When the first TiAlC absorption film 5, the second TiAlC absorption film 7, the third TiAlC absorption film 9 and the fourth TiAlC absorption film are deposited by atomic layer deposition, the precursors used include Al(CH3)3 and TiCl4;

[0058] When the first SiO2 dielectric film 6, the second SiO2 dielectric film 8, the third SiO2 dielectric film 10 and the fourth SiO2 dielectric film are deposited by atomic layer deposition, the precursors used include diisopropylaminosilane and O3;

[0059] When the Al2O3 water-blocking film 13 is deposited by atomic layer deposition, the precursors used include Al(CH3)3 and O3.

[0060] Example 2

[0061] This embodiment provides a black film, which includes a first stacked film layer, a second stacked film layer, a third stacked film layer, a fourth stacked film layer, a fifth stacked film layer, and a sixth stacked film layer (light enters the black film from a surface of the sixth stacked film layer away from the fifth stacked film layer);

[0062] The first stacked film layer includes a first TiAlC absorption film with a thickness of 200 nm and a first SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0063] The second stacked film layer includes a second TiAlC absorption film with a thickness of 200 nm and a second SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0064] The third stacked film layer includes a third TiAlC absorption film with a thickness of 200 nm and a third SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0065] The fourth stacked film layer includes a fourth TiAlC absorption film with a thickness of 200 nm and a fourth SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0066] The fifth stacked film layer includes a fifth TiAlC absorption film with a thickness of 200 nm and a fifth SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0067] The sixth stacked film layer includes a sixth TiAlC absorption film with a thickness of 200 nm and a sixth SiO2 dielectric film with a thickness of 30 nm which are stacked;

[0068] The refractive index of the first TiAlC absorption film, the second TiAlC absorption film, the third TiAlC absorption film, the fourth TiAlC absorption film, the fifth TiAlC absorption film and the sixth TiAlC absorption film is 2.3, and the absorption coefficient is 1.3;

[0069] The refractive index of the first SiO2 dielectric film, the second SiO2 dielectric film, the third SiO2 dielectric film, the fourth SiO2 dielectric film, the fifth SiO2 dielectric film and the sixth SiO2 dielectric film is 1.45;

[0070] The bottom of the black film is the first TiAlC absorption film, and the top is the sixth SiO2 dielectric film. Between the sixth TiAlC absorption film and the sixth SiO2 dielectric film in the stacked film layer on the top of the black film, there are arranged a first Al2O3 water-blocking film with a thickness of 15nm and a second ZrO2 water-blocking film with a thickness of 5nm.

[0071] The preparation method of the black film comprises:

[0072] On the surface of the substrate, atomic layer deposition is sequentially performed to obtain a first TiAlC absorption film, a first SiO2 dielectric film, a second TiAlC absorption film, a second SiO2 dielectric film, a third TiAlC absorption film, a third SiO2 dielectric film, a fourth TiAlC absorption film, a fourth SiO2 dielectric film, a fifth TiAlC absorption film, a fifth SiO2 dielectric film, a sixth TiAlC absorption film, a first Al2O3 water-blocking film, a second Al2O3 water-blocking film and a sixth SiO2 dielectric film;

[0073] The temperature during the atomic layer deposition of the first TiAlC absorption film, the first SiO2 dielectric film, the second TiAlC absorption film, the second SiO2 dielectric film, the third TiAlC absorption film, the third SiO2 dielectric film, the fourth TiAlC absorption film, the fourth SiO2 dielectric film, the fifth TiAlC absorption film, the fifth SiO2 dielectric film, the sixth TiAlC absorption film, the first Al2O3 water-blocking film, the second Al2O3 water-blocking film and the sixth SiO2 dielectric film is 350-500°C;

[0074] When the first TiAlC absorption film, the second TiAlC absorption film, the third TiAlC absorption film, the fourth TiAlC absorption film, the fifth TiAlC absorption film and the sixth TiAlC absorption film are deposited by atomic layer deposition, the precursors used include Al(CH3)3 and TiCl4;

[0075] When the first SiO2 dielectric film, the second SiO2 dielectric film, the third SiO2 dielectric film, the fourth SiO2 dielectric film, the fifth SiO2 dielectric film and the sixth SiO2 dielectric film are deposited by atomic layer deposition, the precursors used include diisopropylaminosilane and O3;

[0076] When the first Al2O3 water-blocking film and the second Al2O3 water-blocking film are deposited by atomic layer deposition, the precursors used include Al(CH3)3 and O3.

[0077] Example 3

[0078] This embodiment provides a black film, which includes a first stacked film layer, a second stacked film layer, a third stacked film layer, a fourth stacked film layer, a fifth stacked film layer, a sixth stacked film layer and a seventh stacked film layer (light enters the black film from a surface of the seventh stacked film layer away from the sixth stacked film layer);

[0079] The first stacked film layer includes a first TiAlC absorption film with a thickness of 15 nm and a first SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0080] The second stacked film layer includes a second TiAlC absorption film with a thickness of 15 nm and a second SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0081] The third stacked film layer includes a third TiAlC absorption film with a thickness of 15 nm and a third SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0082] The fourth stacked film layer includes a fourth TiAlC absorption film with a thickness of 15 nm and a fourth SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0083] The fifth stacked film layer includes a fifth TiAlC absorption film with a thickness of 15 nm and a fifth SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0084] The sixth stacked film layer includes a sixth TiAlC absorption film with a thickness of 15 nm and a sixth SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0085] The seventh stacked film layer includes a seventh TiAlC absorption film with a thickness of 15 nm and a seventh SiO2 dielectric film with a thickness of 100 nm which are stacked;

[0086] The refractive index of the first TiAlC absorption film, the second TiAlC absorption film, the third TiAlC absorption film, the fourth TiAlC absorption film, the fifth TiAlC absorption film, the sixth TiAlC absorption film and the seventh TiAlC absorption film is 2.3, and the absorption coefficient is 1.3;

[0087] The refractive index of the first SiO2 dielectric film, the second SiO2 dielectric film, the third SiO2 dielectric film, the fourth SiO2 dielectric film, the fifth SiO2 dielectric film, the sixth SiO2 dielectric film and the seventh SiO2 dielectric film is 1.46;

[0088] The bottom of the black film is the first TiAlC absorption film, the top is the sixth SiO2 dielectric film, and an Al2O3 water-blocking film with a thickness of 5 nm is arranged between the seventh TiAlC absorption film and the seventh SiO2 dielectric film in the stacked film layer on the top of the black film.

[0089] The preparation method of the black film comprises:

[0090] On the surface of the substrate, atomic layer deposition is sequentially performed to obtain a first TiAlC absorption film, a first SiO2 dielectric film, a second TiAlC absorption film, a second SiO2 dielectric film, a third TiAlC absorption film, a third SiO2 dielectric film, a fourth TiAlC absorption film, a fourth SiO2 dielectric film, a fifth TiAlC absorption film, a fifth SiO2 dielectric film, a sixth TiAlC absorption film, a sixth SiO2 dielectric film, a seventh TiAlC absorption film, an Al2O3 water-blocking film and a seventh SiO2 dielectric film;

[0091] The temperature during the atomic layer deposition of the first TiAlC absorption film, the first SiO2 dielectric film, the second TiAlC absorption film, the second SiO2 dielectric film, the third TiAlC absorption film, the third SiO2 dielectric film, the fourth TiAlC absorption film, the fourth SiO2 dielectric film, the fifth TiAlC absorption film, the fifth SiO2 dielectric film, the sixth TiAlC absorption film, the sixth SiO2 dielectric film, the seventh TiAlC absorption film, the Al2O3 water-blocking film and the seventh SiO2 dielectric film is 350-500°C;

[0092] When the first TiAlC absorption film, the second TiAlC absorption film, the third TiAlC absorption film, the fourth TiAlC absorption film, the fifth TiAlC absorption film, the sixth TiAlC absorption film and the seventh TiAlC absorption film are deposited by atomic layer deposition, the precursors used include Al(CH3)3 and TiCl4;

[0093] When the first SiO2 dielectric film, the second SiO2 dielectric film, the third SiO2 dielectric film, the fourth SiO2 dielectric film, the fifth SiO2 dielectric film, the sixth SiO2 dielectric film and the seventh SiO2 dielectric film are deposited by atomic layer deposition, the precursors used include diisopropylaminosilane and O3;

[0094] When Al2O3 water-blocking film is deposited by atomic layer deposition, the precursors used include Al(CH3)3 and O3.

[0095] Example 4

[0096] This embodiment provides a black film, except that the first TiAlC absorption film, the second TiAlC absorption film, the third TiAlC absorption film and the fourth TiAlC absorption film are replaced by the first TiN absorption film, the second TiN absorption film, the third TiN absorption film and the fourth TiN absorption film of the same thickness respectively;

[0097] The first TiN absorption film, the second TiN absorption film, the third TiN absorption film and the fourth TiN absorption film have a refractive index of 2.2 and an absorption coefficient of 0.5, and the rest are the same as those in Example 1.

[0098] Example 5

[0099] This embodiment provides a black film, except that the first SiO2 dielectric film, the second SiO2 dielectric film, the third SiO2 dielectric film, and the fourth SiO2 dielectric film are replaced by the first MgF dielectric film, the second MgF dielectric film, the third MgF dielectric film, and the fourth MgF dielectric film of the same thickness respectively;

[0100] Except that the refractive index of the first MgF dielectric film, the second MgF dielectric film, the third MgF dielectric film and the fourth MgF dielectric film is 1.35, the rest are the same as those in the first embodiment.

[0101] Example 6

[0102] This embodiment provides a black film, in addition to replacing the first TiAlC absorption film and the second TiAlC absorption film with the first TiN absorption film and the second TiN absorption film of the same thickness, and replacing the first SiO2 dielectric film and the second SiO2 dielectric film with the first MgF dielectric film and the second MgF dielectric film of the same thickness;

[0103] The refractive index of the first TiN absorption film and the second TiN absorption film is 2.2, and the absorption coefficient is 0.5; and the refractive index of the first MgF dielectric film and the second MgF dielectric film is 1.35, and the rest is the same as that of the first embodiment.

[0104] Example 7

[0105] This embodiment provides a black film, which is the same as Embodiment 1 except that the Al2O3 water-blocking film is replaced by ZrO2 of the same thickness.

[0106] Example 8

[0107] This embodiment provides a black film, which is the same as that of Embodiment 1 except that the thickness of the Al2O3 water-blocking film is 2 nm.

[0108] Example 9

[0109] This embodiment provides a black film, which is the same as that of Embodiment 1 except that the thickness of the Al2O3 water-blocking film is 30 nm.

[0110] Comparative Example 1

[0111] This comparative example provides a black film, which is the same as Example 1 except that the Al2O3 water-blocking film arranged between the fourth TiAlC absorption film and the fourth SiO2 dielectric film in the stacked film layer on the top of the black film is omitting, and an Al2O3 water-blocking film of the same thickness is added between the third TiAlC absorption film and the third SiO2 dielectric film.

[0112] Comparative Example 2

[0113] This comparative example provides a black film, which is the same as Example 1 except that the Al2O3 water-blocking film disposed between the fourth TiAlC absorption film and the fourth SiO2 dielectric film in the stacked film layer on the top of the black film is omitted.

[0114] The initial reflective performance test of the black film provided in the above embodiment and comparative example was carried out, and the reflectivity of the black film at a wavelength of 400nm, a wavelength of 600nm and a wavelength of 800nm ​​in the initial state was obtained as shown in Table 1; wherein, the curve of the reflectivity of the black film provided in Example 1 changing with the wavelength is shown in Figure 1 shown.

[0115] The black films provided in the above embodiments and comparative examples were subjected to a 600-hour double 85 test (the black films were placed in an environment with a temperature of 85° C. and a humidity of 85%), and then the reflective performance of the black films after the 600-hour double 85 test was tested. The reflectivity of the black films at a wavelength of 400 nm, at a wavelength of 600 nm, and at a wavelength of 800 nm after the 600-hour double 85 test was obtained as shown in Table 2; wherein, the curve of the reflectivity of the black film provided in Example 1 after the 600-hour double 85 test as a function of wavelength is shown in Table 2. Figure 1 shown.

[0116] The black films provided in the above embodiments and comparative examples were subjected to a 1000-hour double 85 test (the black films were placed in an environment with a temperature of 85°C and a humidity of 85%), and the reflective performance of the black films after the 1000-hour double 85 test was tested. The reflectivity of the black films at a wavelength of 400nm, 600nm, and 800nm ​​after the 1000-hour double 85 test was obtained as shown in Table 3; wherein, the curve of the reflectivity of the black film provided in Example 1 after the 1000-hour double 85 test as a function of wavelength is shown in Table 3. Figure 1 shown.

[0117] Table 1

[0118]

[0119] Table 2

[0120]

[0121] Table 3

[0122]

[0123]

[0124] From Tables 1 to 3 and Figure 1 We can get:

[0125] (1) The black films provided in Examples 1 to 6 of the present invention all exhibited low reflectivity and excellent light absorption performance in the initial state, after 600 hours of double 85 test, and after 1000 hours of double 85 test;

[0126] (2) By comparing Example 1 with Example 7, it can be seen that, compared with ZrO2, using Al2O3 as the constituent material of the water-blocking film can make the black film show more excellent stability and show lower reflectivity after the double 85 test. This is because the aluminum oxide mainly composed of α-Al2O3 has a stable hexagonal crystal structure. This structure is relatively compact, the atoms inside the crystal are arranged regularly, and there are fewer pores and defects. It is difficult for water molecules to find a large enough channel or gap to penetrate, so the water barrier performance is better; in addition, the Al-O bond has a strong ionic bond component and a large bond energy. When water molecules come into contact with the Al2O3 surface, it is difficult to break the Al-O bond and enter the water-blocking film. At the same time, due to the effect of chemical bonds, the Al2O3 surface has relatively weak adsorption and binding capabilities for water molecules, which is not conducive to the diffusion and transmission of water molecules in the water-blocking film, thus showing better water-blocking performance. Although the Zr-O bond also has a certain bond energy and can have a certain water-blocking performance, compared with the Al-O bond, its chemical bond characteristics make the ZrO2 surface likely to have a certain adsorption effect on water molecules, making it easier to form diffusion channels in the film, thereby reducing its water-blocking performance; therefore, using Al2O3 as the material of the water-blocking film is better than ZrO2;

[0127] (3) By comparing Example 1 with Examples 8 and 9, it can be seen that the thickness of the water-blocking film in the present invention affects the performance of the black film; when the thickness of the water-blocking film is 5 to 20 nm, the black film exhibits lower reflectivity and better water resistance. This is because: when the water-blocking film is too thick, since the refractive index of Al2O3 is higher than that of SiO2, it will bring about an unfavorable interference effect, resulting in a higher overall reflectivity; when the water-blocking film is too thin, Al2O3 is difficult to form a continuous film, and the water-blocking effect is poor;

[0128] (4) By comparing Example 1 with Comparative Examples 1 and 2, it can be seen that in the present invention, at least one water-blocking film is arranged between the absorbing film and the dielectric film in the laminated film layer on the top of the black film (the laminated film layer where light is incident and exposed to the external environment), thereby preventing water vapor from corroding the absorbing film in the laminated film layer on the top of the black film, thereby enhancing the water vapor corrosion resistance of the black film and avoiding water failure of the black film in an environment with high humidity; the black film provided by the present invention has passed the double 85 environmental test and has a wider range of applications; in addition, since a dielectric film with a lower refractive index needs to be used on the top of the black film, and the absorbing film in the laminated film layer on the top of the black film needs to avoid water vapor corrosion; therefore, the water-blocking film can only be arranged between the dielectric film and the absorbing film on the top of the black film, which not only achieves the enhancement of the water resistance of the black film, but also avoids affecting the light absorption performance of the black film.

[0129] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A black film, characterized in that: The black film comprises at least two stacked film layers; the stacked film layers comprise an absorption film and a dielectric film which are stacked; The top of the black film is a dielectric film, and at least one layer of water-blocking film is arranged between the absorption film and the dielectric film in the stacked film layers on the top of the black film.

2. The black film according to claim 1, characterized in that: The refractive index of the absorption film in each of the stacked film layers is higher than that of the dielectric film.

3. The black film according to claim 1 or 2, characterized in that: The refractive index of the absorption film in each layer of the stacked film is independently 2 to 2.5, and the absorption coefficient is independently not less than 1.

4. The black film according to any one of claims 1 to 3, characterized in that: The refractive index of the dielectric film in each layer of the stacked film is independently 1.35 to 1.

7.

5. The black film according to any one of claims 1 to 4, characterized in that: The thickness of the absorption film in each layer of the stacked film is independently 15 to 200 nm; Preferably, the material of the absorption film in each layer of the stacked film layer independently includes any one of TiAlC, TiN or TiAlN or a combination of at least two of them, preferably TiAlC.

6. The black film according to any one of claims 1 to 5, characterized in that: The thickness of the dielectric film in each layer of the stacked film is independently 30 to 100 nm; Preferably, the material of the dielectric film in each layer of the stacked film layer independently includes any one of SiO2, MgF or Al2O3 or a combination of at least two of them, preferably SiO2.

7. The black film according to any one of claims 1 to 6, characterized in that: The thickness of the water-blocking film is 5 to 20 nm; Preferably, the material of the water-blocking film includes any one of Al2O3, ZrO2 or TiO2 or a combination of at least two thereof, preferably Al2O3.

8. A method for preparing the black film according to any one of claims 1 to 7, characterized in that: The preparation method comprises: On the surface of the substrate, an absorption film and a dielectric film are repeatedly deposited in sequence by atomic layer deposition; When the absorption film is deposited for the last time, at least one layer of water-blocking film is first deposited on the surface of the obtained absorption film by atomic layer deposition, and then the dielectric film is deposited.

9. An application of the black film according to any one of claims 1 to 7, characterized in that: The black film is used in the fields of optics, electronics or energy.

10. The use according to claim 9, characterized in that: The black film is used in the optical field as a component of an optical device or a glass curtain wall; The optical device includes an optical microscope and an optical laser, and the black film is placed on the inner wall of the cavity of the optical microscope and the optical laser; The black film is used as a light-absorbing film for the glass curtain wall; Preferably, the black film is used in the field of electronics as a component of a light-absorbing cover in a space probe; Preferably, the black film is used in the energy field as a heat absorbing material in a solar water heater.

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