Black film, preparation method thereof and optical device
By combining coating technology and dry or wet etching in the preparation of black films, selective etching is solved according to the etching rate of the material, and the problems of complex and high cost of black film preparation in the prior art are solved, achieving high efficiency and low efficiency The cost of the preparation of porous structure black film improves the stability and optical properties of the film layer.
Patent Information
- Application Number
- CN202411225559.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-03
- Publication Date
- 2024-12-13
AI Technical Summary
The existing black film preparation methods have problems such as unstable mechanical properties and uniformity control, complex process, high cost, and difficult to match the interface stability between film layers, especially when preparing high-absorbing film layers with specific wavelengths.
Using coating technology commonly used in industries and laboratories combined with dry or wet etching methods, composite material thin films are deposited and selectively etched to obtain porous black films according to the etching rates of the first and second materials. , high-efficiency and low-cost black films are prepared by cleaning and drying.
It realizes efficient preparation of black films with porous structures without the need to modify the equipment hardware, reducing costs and improving the stability of the optical and mechanical properties of the film layer.
Smart Images
Figure CN119121131A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of optical technology, and in particular to a black film and a preparation method thereof, and an optical device. Background Art
[0002] Black film, due to its extremely high light absorption rate, is widely used in optical sensors for aerospace telescopes, infrared cameras, medical fields, vehicles and mobile devices to reduce stray light and improve precision and signal-to-noise ratio. At present, the main technical difficulty in preparing black film is how to prepare a high-absorption film layer suitable for a specific wavelength (in most cases, the visible light domain) under the condition of ensuring reasonable cost (such as thickness, chemical composition, equipment and process selection).
[0003] Commonly used methods for coating black film include: 1) carbon nanotube ink spraying, which has the problem of unstable control of mechanical properties and uniformity of the obtained black film; 2) surface treatment of the substrate by etching or laser to achieve a texturing effect, and this preparation method has high requirements on the thermal stability of the substrate; 3) changing the surface morphology of the film by adjusting the coating process parameters, which has the problem of more preparation process steps and higher cost; 4) design and vacuum coating of multi-layer films, which has a relatively complex preparation process, and the interface stability between film layers and the optical properties between film layers need to match each other. Summary of the invention
[0004] The purpose of the present invention is to provide a black film and a preparation method thereof, and an optical device. A black film with a porous structure is prepared by combining a coating technology commonly used in industry and laboratories with a dry or wet etching method. There is no need to modify the equipment hardware, and it is efficient and low-cost.
[0005] The embodiment of the present invention is achieved as follows:
[0006] According to a first aspect of an embodiment of the present invention, a method for preparing a black film is provided, the method comprising:
[0007] Depositing a composite material film on a substrate, wherein the composite material film comprises a first material and a second material, and the first material and the second material have different etching rates during dry etching or wet etching;
[0008] Performing dry etching or wet etching on the composite material film to obtain a porous absorption film;
[0009] The porous absorbent membrane is sequentially cleaned and dried.
[0010] As an practicable manner, the step of depositing a composite material film on a substrate includes:
[0011] The composite film is deposited on the substrate by physical vapor deposition, chemical vapor deposition or atomic layer deposition.
[0012] As an practicable manner, the step of dry etching or wet etching the composite material film to obtain a porous absorption film includes:
[0013] The composite material film is dry-etched by etching gas to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
[0014] As an practicable manner, the etching gas is Cl2, BCl3, Ar, N2, CHF3 or C2H4.
[0015] As an practicable manner, the step of dry etching or wet etching the composite material film to obtain a porous absorption film includes:
[0016] The composite material film is wet-etched by an etching solution to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
[0017] As an practicable manner, the etching solution is oxalic acid, hydrofluoric acid, sodium carbonate, sodium hydride, ammonia water or phosphoric acid.
[0018] As an practicable manner, the sequentially cleaning and drying of the porous absorption membrane includes:
[0019] Cleaning the porous absorption membrane by an ultrasonic cleaning machine;
[0020] The porous absorption membrane is dried by a centrifuge or a drying machine, wherein the drying temperature of the drying machine is between 40 and 120°C.
[0021] As an practicable manner, the thickness of the composite material film is between 50 and 1000 nm.
[0022] As an practicable manner, the substrate is glass, crystalline silicon, sapphire or plastic.
[0023] As an practicable manner, the first material and the second material are single-element materials or compound materials.
[0024] According to a second aspect of the embodiments of the present invention, a black film is provided, which is prepared by using the above-mentioned black film preparation method.
[0025] According to a third aspect of the embodiments of the present invention, an optical device is provided, comprising the above-mentioned black film.
[0026] The beneficial effects of the embodiments of the present invention include:
[0027] The method for preparing the black film includes: depositing a composite material film on a substrate, wherein the composite material film includes a first material and a second material, and the first material and the second material have different etching rates during dry etching or wet etching; dry etching or wet etching the composite material film to obtain a porous absorption film; and sequentially cleaning and drying the porous absorption film. Compared with several common methods for preparing black films in the prior art, the method for preparing a black film provided in the present application first deposits a composite material film on the surface of a substrate through a coating technology commonly used in industry and laboratories, wherein the composite material film includes a first material and a second material, and then selectively etches away one of the materials while retaining the other material according to the different etching rates of the first material and the second material during dry etching or wet etching, combined with a dry or wet etching method, thereby preparing a black film having a porous structure inside the other material, without the need to modify existing equipment hardware, and having the advantages of high efficiency and low cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.
[0029] Figure 1 One of the flow charts of the method for preparing the black film provided in an embodiment of the present invention;
[0030] Figure 2 The second flowchart of the method for preparing the black film provided by the embodiment of the present invention;
[0031] Figure 3 Flow chart 3 of the method for preparing the black film provided by an embodiment of the present invention;
[0032] Figure 4 Flow chart 4 of the method for preparing a black film provided in an embodiment of the present invention;
[0033] Figure 5 Flow chart 5 of the method for preparing the black film provided in an embodiment of the present invention;
[0034] Figure 6 One of the structural schematic diagrams of the black film provided by an embodiment of the present invention;
[0035] Figure 7 The second structural schematic diagram of the black film provided in the embodiment of the present invention.
[0036] Icon: 100 - black film; 10 - substrate; 20 - composite material film; 21 - first material; 22 - second material. DETAILED DESCRIPTION
[0037] The embodiments set forth below represent information necessary to enable those skilled in the art to practice the embodiments, and illustrate the best mode for practicing the embodiments. After reading the following description with reference to the accompanying drawings, those skilled in the art will understand the concepts of the present disclosure, and will recognize the applications of these concepts not specifically proposed herein. It should be understood that these concepts and applications are within the scope of the present disclosure and the appended claims.
[0038] It should be understood that although the terms first, second, etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.
[0039] It should be understood that when an element (such as a layer, region or substrate) is referred to as "on another element" or "extending onto another element", it can be directly on another element or directly extended onto another element, or there can also be an intervening element. On the contrary, when an element is referred to as "directly on another element" or "directly extending onto another element", there is no intervening element. Similarly, it should be understood that when an element (such as a layer, region or substrate) is referred to as "on another element" or "extending onto another element", it can be directly on another element or directly extended onto another element, or there can also be an intervening element. On the contrary, when an element is referred to as "directly on another element" or "extending directly onto another element", there is no intervening element. It should also be understood that when an element is referred to as "connected" or "coupled" to another element, it can be directly connected or coupled to another element, or there can be an intervening element. On the contrary, when an element is referred to as "directly connected" or "directly coupled" to another element, there is no intervening element.
[0040] Relative terms such as “below” or “above” or “upper” or “lower” or “horizontal” or “vertical” may be used herein to describe the relationship of one element, layer or region to another element, layer or region as shown in the figures.
[0041] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms as well. It should also be understood that when used herein, the term "comprising" indicates the presence of the features, integers, steps, operations, elements, and / or parts, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups of the above.
[0042] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. It should also be understood that the terms used herein should be interpreted as having the same meaning as they do in the context of this specification and the relevant art, and should not be interpreted in an idealized or overly formal sense, unless clearly defined in this article.
[0043] There are many existing methods for preparing black (high absorption) films or coatings: for example, ink or powder spraying, which has the problems of thick film layer, poor bonding with the substrate, unstable mechanical properties and uniformity control of the obtained black film, and environmentally unfriendly preparation process; another example is the surface treatment of the substrate by etching or laser to achieve a texturing effect, and this preparation method has high requirements on the thermal stability of the substrate; another example is the preparation of surface microstructure to achieve high absorption of the material, but it will face the problems of complex process and high cost in production, preparation and application; another example is vacuum plating of multi-layer films, which has the problems of complex structure and high difficulty in material matching.
[0044] To solve the above problems, please refer to Figures 1 to 7 The present application provides a black film 100 and a preparation method thereof, and an optical device. The black film 100 with a porous structure is prepared by combining the coating technology commonly used in industry and laboratories with a dry or wet etching method. There is no need to modify the equipment hardware, and it is efficient and low-cost.
[0045] Specifically, Figure 1 , Figure 6 and Figure 7 As shown, in a first aspect of an embodiment of the present application, a method for preparing a black film 100 is provided, the method comprising:
[0046] S110, depositing a composite material film 20 on the substrate 10, wherein the composite material film 20 includes a first material 21 and a second material 22, and the first material 21 and the second material 22 have different etching rates during dry etching or wet etching;
[0047] It should be noted that, first of all, Figure 1 and Figure 6As shown, a substrate 10 is provided, and the substrate 10 is used as a material basis for thin film deposition, wherein the surface of the substrate 10 needs to be smooth, dry, and clean, so as to facilitate thin film deposition on the surface of the substrate 10 in subsequent steps; secondly, please continue to refer to Figure 1 and Figure 6 A composite material film 20 is deposited on a substrate 10, wherein the composite material film 20 includes a first material 21 and a second material 22, and the first material 21 and the second material 22 have different etching rates when the etched medium is selectively etched during dry etching or wet etching. Regarding the actual selection of the first material 21 and the second material 22, those skilled in the art should be able to make reasonable selections and designs according to actual conditions, and no specific restrictions are made here.
[0048] S210, performing dry etching or wet etching on the composite material film 20 to obtain a porous absorption film;
[0049] S310, sequentially washing and drying the porous absorption membrane.
[0050] It should be noted that, again, please refer to Figure 7 , the composite material film 20 is dry-etched or wet-etched. Since the first material 21 and the second material 22 have different etching rates during dry etching or wet etching, one of the materials can be selectively etched away while retaining the other material when the composite material film 20 is dry-etched or wet-etched, thereby obtaining a porous absorption film having the other material; finally, the porous absorption film is sequentially cleaned and dried to remove the etching medium or the generated by-products remaining on the surface of the porous absorption film, and then dried to prepare a black film 100 with a porous structure.
[0051] For example, Figure 6 and Figure 7 As shown, in this embodiment, the etching medium may selectively etch away the second material 22 while retaining the first material 21, thereby obtaining a porous absorption membrane having the first material 21; of course, in other embodiments, the etching medium may selectively etch away the first material 21 while retaining the second material 22, thereby obtaining a porous absorption membrane having the second material 22. Regarding which material to selectively etch away while retaining another material in the actual preparation process, those skilled in the art should be able to make reasonable choices and designs according to actual conditions, and no specific restrictions are made here. The following explanation is given by taking the selective etching away of the second material 22 while retaining the first material 21, thereby obtaining a porous absorption membrane having the first material 21 as an example.
[0052] Regarding the actual size of the difference in etching rate between the first material 21 and the second material 22 during dry etching or wet etching, those skilled in the art should be able to make reasonable selections and designs according to actual conditions, and no specific restrictions are made here. It should be understood that, although the etching rates of the first material 21 and the second material 22 during dry etching or wet etching are different, the second material 22 can be selectively etched while retaining the first material 21, but it is inevitable that part of the first material 21 away from the substrate 10 is etched away, while part of the second material 22 close to the substrate 10 is not etched away. This is because the etching medium will first contact and react with the side away from the substrate 10, and then it can pass through the pores that have been formed inside the composite film 20 and contact and react with the side close to the substrate 10, but this does not affect the main purpose of obtaining a porous absorption film through the etching process. It should be noted that the etching medium cannot etch the composite film 20 through the surface of the substrate 10.
[0053] Compared with several common black film preparation methods in the prior art, the black film preparation method 100 provided in the present application first deposits a composite material film 20 on the surface of the substrate 10 through the coating technology commonly used in industry and laboratories, wherein the composite material film 20 includes a first material 21 and a second material 22, and then according to the different etching rates of the first material 21 and the second material 22 during dry etching or wet etching, combined with the dry or wet etching method, one of the materials is selectively etched away while retaining the other material, thereby preparing a black film 100 with a porous structure inside the other material, without the need to modify the existing equipment hardware, and has the advantages of high efficiency and low cost.
[0054] like Figure 2 and Figure 6 As shown, as an practicable manner, S110, depositing a composite material film 20 on a substrate 10 includes:
[0055] S111 , depositing a composite material film 20 on the substrate 10 by physical vapor deposition, chemical vapor deposition or atomic layer deposition.
[0056] It should be noted that the above-mentioned physical vapor deposition includes vacuum evaporation coating, vacuum sputtering coating and vacuum ion coating. Regarding the actual selection of the coating technology used to deposit the composite material film 20, those skilled in the art should be able to make reasonable selections and designs according to actual conditions, and no specific restrictions are made here.
[0057] like Figure 3 and Figure 7 As shown, as an practicable method, S210, dry etching or wet etching the composite material film 20 to obtain a porous absorption film includes:
[0058] S211, dry-etching the composite material film 20 with an etching gas to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
[0059] As an practicable method, the etching gas is Cl2, BCl3, Ar, N2, CHF3 or C2H4 etc. Regarding the actual selection of etching gas, those skilled in the art should be able to make reasonable selection and design according to the actual situation, and no specific limitation is made here.
[0060] like Figure 4 and Figure 7 As shown, as an practicable method, S210, dry etching or wet etching the composite material film 20 to obtain a porous absorption film includes:
[0061] S212, wet-etching the composite material film 20 with an etching solution to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
[0062] As an practicable method, the etching solution is a compound such as oxalic acid, hydrofluoric acid, sodium carbonate, sodium hydride, ammonia water or phosphoric acid. Regarding the actual selection of the etching solution, those skilled in the art should be able to make a reasonable selection and design according to the actual situation, and no specific limitation is made here.
[0063] like Figure 5 As shown, as an implementable method, S310, sequentially cleaning and drying the porous absorption membrane includes:
[0064] S311, cleaning the porous absorption membrane by an ultrasonic cleaning machine;
[0065] S312, drying the porous absorption membrane by a centrifuge or a drying machine, wherein the drying temperature of the drying machine is between 40 and 120°C.
[0066] It should be noted that, since the above-mentioned etching process will leave etching medium or generate by-products on the surface of the porous absorption membrane, the obtained porous absorption membrane needs to be cleaned first. For example, in this embodiment, an ultrasonic cleaning machine is used to clean the porous absorption membrane to ensure that the surface of the porous absorption membrane can be cleaned. Since water stains will remain on the surface of the porous absorption membrane after cleaning, the cleaned porous absorption membrane needs to be dried again. For example, the porous absorption membrane can be spun dry by a centrifuge or dried by a dryer. It should be noted that the drying temperature should not be too high. Optionally, the drying temperature is between 40 and 120°C, such as 40°C, 60°C, 80°C, 100°C or 120°C, so as to avoid damage to the porous absorption membrane and cause the porous absorption membrane to become brittle and break easily.
[0067] like Figure 6 and Figure 7 As shown, as an practicable manner, the thickness of the composite film 20 is between 50 and 1000 nm. For example, the thickness of the composite film 20 is 50 nm, 100 nm, 200 nm, 500 nm, 800 nm or 1000 nm. The performance of the composite film 20 can be adjusted accordingly by the actual selection of the first material 21 and the second material 22 and the ratio of the first material 21 and the second material 22.
[0068] As an practicable manner, the substrate 10 is glass, crystalline silicon, sapphire or plastic. Regarding the actual selection of the substrate 10, those skilled in the art should be able to make reasonable selections and designs according to actual conditions, and no specific restrictions are made here. As an practicable manner, the first material 21 and the second material 22 are single-substance materials or compound materials, wherein the single-substance materials may be Si, Ge, Au, Cr, Ni, W, Al, Mo, Pt, Ag or Ti, etc., and the compound materials may be nitrides, oxides or carbides. Regarding the actual selection of single-substance materials and compound materials, those skilled in the art should be able to make reasonable selections and designs according to actual conditions, and no specific restrictions are made here.
[0069] like Figure 6 and Figure 7 As shown, in a second aspect of an embodiment of the present application, a black film 100 is provided, and the black film 100 is prepared by using the above-mentioned method for preparing the black film 100.
[0070] It should be noted that the specific structure of the black film 100 provided in this embodiment is the same as the preparation method of the black film 100 in the previous text. Those skilled in the art can infer the specific structure of the black film 100 based on the description of the preparation method of the black film 100 in the previous text, and this application will not repeat the description. Since the black film 100 provided in this embodiment is prepared by the preparation method of the black film 100 described above, the black film 100 has the same beneficial effects as the preparation method of the black film 100 described above, and will not be repeated here.
[0071] According to a third aspect of the embodiments of the present application, an optical device is provided, and the optical device includes the above-mentioned black film 100. Since the structure and beneficial effects of the black film 100 have been described in detail in the above-mentioned embodiments, they will not be described in detail here.
[0072] The above description is only an optional embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
[0073] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.
Claims
1. A method for preparing a black film, characterized in that: The method comprises: Depositing a composite material film on a substrate, wherein the composite material film comprises a first material and a second material, and the first material and the second material have different etching rates during dry etching or wet etching; Performing dry etching or wet etching on the composite material film to obtain a porous absorption film; The porous absorbent membrane is sequentially cleaned and dried.
2. The method for preparing the black film according to claim 1, characterized in that: The step of depositing a composite material film on a substrate comprises: The composite film is deposited on the substrate by physical vapor deposition, chemical vapor deposition or atomic layer deposition.
3. The method for preparing the black film according to claim 1, characterized in that: The step of dry etching or wet etching the composite material film to obtain a porous absorption film comprises: The composite material film is dry-etched by etching gas to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
4. The method for preparing the black film according to claim 3, characterized in that: The etching gas is Cl2, BCl3, Ar, N2, CHF3 or C2H4.
5. The method for preparing the black film according to claim 1, characterized in that: The step of dry etching or wet etching the composite material film to obtain a porous absorption film comprises: The composite material film is wet-etched by an etching solution to obtain a porous absorption film, wherein the etching temperature is between 20 and 150°C.
6. The method for preparing the black film according to claim 5, characterized in that: The etching solution is oxalic acid, hydrofluoric acid, sodium carbonate, sodium hydride, ammonia water or phosphoric acid.
7. The method for preparing a black film according to claim 1, characterized in that: The sequentially cleaning and drying of the porous absorption membrane comprises: Cleaning the porous absorption membrane by an ultrasonic cleaning machine; The porous absorption membrane is dried by a centrifuge or a drying machine, wherein the drying temperature of the drying machine is between 40 and 120°C.
8. The method for preparing a black film according to claim 1, characterized in that: The thickness of the composite material film is between 50 and 1000 nm.
9. The method for preparing a black film according to claim 1, characterized in that: The substrate is glass, crystalline silicon, sapphire or plastic.
10. The method for preparing a black film according to claim 1, characterized in that: The first material and the second material are single-element materials or compound materials.
11. A black film, characterized in that: The black film is prepared by the method for preparing the black film according to any one of claims 1 to 10.
12. An optical device, characterized in that: Comprising the black film as claimed in claim 11.