Total reflection film and preparation method thereof, and reflective device

Abstract

The present application provides a total reflection film and a preparation method thereof, and a reflective device, wherein the total reflection film includes a fluorine-containing inorganic compound and a fluorine-containing polymer, wherein the fluorine-containing inorganic compound includes oxides of aluminum, magnesium, and silicon; the mass percentage of the fluorine-containing inorganic compound in the total reflection film is m1, and the mass percentage of the fluorine-containing polymer in the total reflection film is m2, 80%≤m1<100%, 0%<m2≤20%, thereby improving the optical performance of the total reflection film while improving its interface adhesion performance.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to a total reflection film and a preparation method thereof, and a reflective device. Background Art

[0002] A liquid-cooled data center is a data center that uses coolant as a cooling medium. The equipment in the data center is immersed in the coolant to remove heat through the coolant. The reflective devices in the equipment (such as the prisms in the equipment) will also be immersed in the coolant for a long time. If the adhesion between the total reflection film on the surface of the reflective device and the reflective device body is not good, it will easily fall off during the long-term immersion in the coolant, making it difficult for the equipment in the liquid-cooled data center to operate normally. Summary of the invention

[0003] In order to solve the above technical problems, the present application discloses a total reflection film and its preparation method, and a reflective device, which reduce the refractive index of the total reflection film while improving its interface adhesion performance, so that the reflective device has higher operating stability in the application scenario of liquid-cooled data center.

[0004] In the first aspect, the present application provides a total reflection film, which includes a fluorine-containing inorganic compound and a fluorine-containing polymer, wherein the fluorine-containing inorganic compound includes oxides of aluminum, magnesium, and silicon; the mass percentage of the fluorine-containing inorganic compound in the total reflection film is m1, and the mass percentage of the fluorine-containing polymer in the total reflection film is m2, 80%≤m1<100%, 0%<m2≤20%.

[0005] In some embodiments of the present application, the fluorine-containing inorganic compound has a chemical formula of MSiFH x O y , wherein M includes aluminum and magnesium, 0<x≤0.5, 1.5≤y≤2.0.

[0006] In some embodiments of the present application, the operating wavelength of the total reflection film is not less than 850 nm.

[0007] In some embodiments of the present application, the operating wavelength of the total reflection film is 1250 nm~2000 nm.

[0008] In some embodiments of the present application, the thickness of the total reflection film is 30nm ~ 200nm.

[0009] In some embodiments of the present application, the total reflection film has a porous structure.

[0010] In some embodiments of the present application, the refractive index of the total reflection film is 1.03~1.23.

[0011] In some embodiments of the present application, the fluorine-containing polymer includes at least one of a fluorine-containing epoxy compound and a fluorine-containing acrylate compound.

[0012] In a second aspect, the present application provides a method for preparing the total reflection film as described in the first aspect, comprising the following steps:

[0013] The precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are introduced into the reaction chamber of the CVD equipment with an inert gas atmosphere, so that the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are polymerized on the surface of the reflective device to be coated to form the total reflection film.

[0014] In some embodiments of the present application, the precursor material of the fluorine-containing inorganic compound includes a metal source and a silicon source, the metal source includes at least one of triethylaluminum, triethoxide aluminum and isopropoxide aluminum, the silicon source includes at least one of hexamethyldisiloxane, tetramethyldisiloxane and octamethylcyclotetrasiloxane, and the precursor material of the fluorine-containing polymer includes at least one of hexafluoropropylene oxide dimer, hexafluoropropylene oxide and perfluoroacrylate.

[0015] In some embodiments of the present application, the metal source further includes at least one of dimethyl magnesium and diethyl magnesium.

[0016] In some embodiments of the present application, the temperature of the reaction chamber is 25° C. to 60° C., the pressure is 0.001 atm to 0.2 atm, and the inert gas is nitrogen or helium.

[0017] In some embodiments of the present application, the method further comprises:

[0018] The coated reflective device is immersed in an acid solution for 15 to 30 minutes to form a total reflective film with a porous structure.

[0019] In a third aspect, the present application provides a reflective device, the surface of which has the total reflection film described in the first aspect.

[0020] In some embodiments of the present application, the material of the reflective device includes at least one of polyetherimide, polymethyl methacrylate, silicon, quartz glass and borosilicate glass.

[0021] In some embodiments of the present application, the reflective device includes a prism.

[0022] Compared with the prior art, this application has at least the following beneficial effects:

[0023] The present application provides a total reflection film and a preparation method thereof, and a reflective device, wherein the total reflection film includes a fluorine-containing inorganic compound and a fluorine-containing polymer, wherein the fluorine-containing inorganic compound includes oxides of aluminum, magnesium, and silicon; the mass percentage of the fluorine-containing inorganic compound in the total reflection film is m1, and the mass percentage of the fluorine-containing polymer in the total reflection film is m2, 80%≤m1<100%, 0%<m2≤20%. The total reflection film of the present application includes the above-mentioned fluorine-containing inorganic compound and fluorine-containing polymer, and by regulating the content of the two within the scope of the present application, a total reflection film with a low refractive index and high adhesion performance can be obtained, which improves the optical performance of the total reflection film while improving its interface adhesion performance, and the total reflection film of the present application has good compatibility with the coolant of the liquid-cooled data center, so that the reflective device has higher operating stability in the application scenario of the liquid-cooled data center. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is a schematic structural diagram of a reflective device according to an implementation scheme of the present application.

[0026] Explanation of the reference numerals: reflective device body-1, total reflection film-2. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0029] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0030] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0032] The present application provides a total reflection film, which includes a fluorine-containing inorganic compound and a fluorine-containing polymer. The mass percentage of the fluorine-containing inorganic compound in the total reflection film is m1, and the mass percentage of the fluorine-containing polymer in the total reflection film is m2, 80%≤m1<100%, 0%<m2≤20%.

[0033] The fluorine-containing inorganic compound of the present application is a class of fluorine-containing inorganic compounds, which include oxides of aluminum, magnesium, and silicon, for example, aluminum oxide, magnesium oxide, silicon oxide, etc. The aluminum and magnesium elements in the fluorine-containing inorganic compound are beneficial to reducing the refractive index of the total reflection film; fluorine-containing polymers include but are not limited to fluorine-containing epoxy compounds, fluorine-containing acrylate compounds, etc.

[0034] The inventors have found that when the content of fluorine-containing inorganic compounds in the total reflection film is too low (for example, less than 80%), the content of fluorine-containing polymers in the total reflection film is too high, and the refractive index of the obtained total reflection film is relatively high. The total reflection film of the present application includes the above-mentioned fluorine-containing inorganic compounds and fluorine-containing polymers, and by regulating the content of the two within the scope of the present application, a total reflection film with a low refractive index and high adhesion performance can be obtained, which improves the optical performance of the total reflection film while improving its interface adhesion performance; the inventors have further found that at present, the coolant of the liquid-cooled data center is mainly an organic solvent with low surface energy, such as fluorinated liquid, and the total reflection film of the present application has good compatibility with the coolant of the liquid-cooled data center, so that the optical device containing the total reflection film of the present application can maintain stable performance even if it is immersed in the coolant for a long time, so that the reflective device has higher operating stability in the application scenario of the liquid-cooled data center.

[0035] In an alternative embodiment, the fluorine-containing inorganic compound has the chemical formula MSiFH x O y , wherein M includes aluminum and magnesium, 0<x≤0.5, 1.5≤y≤2.0.

[0036] In an optional embodiment, the operating wavelength of the total reflection film is not less than 850 nm. Preferably, the operating wavelength of the total reflection film is 1250 nm~2000 nm. This is conducive to ensuring the low refractive index characteristics of the total reflection film while maintaining the mechanical strength of the total reflection film.

[0037] In an optional embodiment, the thickness of the total reflection film is not less than 30 nm. Preferably, the thickness of the total reflection film is 50 nm to 120 nm. This is conducive to ensuring the low refractive index characteristics of the total reflection film while maintaining the mechanical strength of the total reflection film.

[0038] In an optional embodiment, the total reflection film has a porous structure. The porous structure is conducive to further reducing the refractive index of the total reflection film, so that the total reflection film has better optical performance.

[0039] In an optional embodiment, the refractive index of the total reflection film is 1.03-1.23, having a low refractive index characteristic.

[0040] In an optional embodiment, the fluorine-containing polymer includes at least one of a fluorine-containing epoxy compound and a fluorine-containing acrylate compound. Specifically, the fluorine-containing epoxy compound may include a fluorine-containing alkylene oxide.

[0041] The present application also provides a method for preparing the total reflection film according to any of the above embodiments, comprising the following steps:

[0042] The precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are introduced into the reaction chamber of the chemical vapor deposition (CVD) equipment with an inert gas atmosphere, so that the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are polymerized on the surface of the reflective device to be coated to form a total reflection film.

[0043] In the present application, the CVD device may be a plasma enhanced chemical vapor deposition (PECVD) device, which is conducive to depositing a fully reflective film with a more controllable film thickness and better uniformity of film thickness. In the process of introducing the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer, the precursor material of the fluorine-containing inorganic compound may be placed in a first raw material pool, and the precursor material of the fluorine-containing polymer may be placed in a second raw material pool, and then the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are simultaneously introduced into the reaction chamber of the CVD device.

[0044] The present application provides a method for preparing a total reflection film, which is based on a PECVD device to simultaneously introduce a precursor material of a fluorine-containing inorganic compound and a precursor material of a fluorine-containing polymer, and polymerizes them on the surface of a reflective device to be coated to form the total reflection film of the present application. The method has the characteristics of simple preparation process and wide source of raw materials. The prepared total reflection film has excellent optical properties and interface adhesion properties.

[0045] In an optional embodiment, the precursor material of the fluorine-containing inorganic compound includes a metal source and a silicon source, the metal source includes at least one of triethylaluminum, triethoxide aluminum and isopropoxide aluminum, and the metal source also includes at least one of dimethylmagnesium and diethylmagnesium; the silicon source includes at least one of hexamethyldisiloxane, tetramethyldisiloxane and octamethylcyclotetrasiloxane; the precursor material of the fluorine-containing polymer includes at least one of hexafluoropropylene oxide dimer, hexafluoropropylene oxide and perfluoroacrylate. The above precursor materials are conducive to forming the total reflection film of the present application.

[0046] In an optional embodiment, the temperature of the reaction chamber is 25°C to 60°C, the pressure is 0.001atm to 0.2atm, and the inert gas is nitrogen or helium. By regulating the temperature and pressure of the reaction chamber within the above range, the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer can be fully polymerized on the surface of the reflective device to be coated, thereby forming a total reflection film with high adhesion performance, low refractive index and uniform thickness.

[0047] In an optional embodiment, the method further includes:

[0048] The coated reflective device is immersed in an acid solution for 15 minutes to 30 minutes to form a total reflection film with a porous structure. In this way, the refractive index of the total reflection film can be further reduced and the optical performance of the total reflection film can be improved.

[0049] The present application has no particular limitation on the acid solution, as long as the purpose of the present application can be achieved. For example, the acid solution can be one or more of hydrochloric acid, glacial acetic acid and citric acid with a mass concentration of 1% to 20%.

[0050] The present application has no particular restrictions on the flow rate of the precursor material of the fluorine-containing inorganic compound and the flow rate of the precursor material of the fluorine-containing polymer. For example, the flow rate of the precursor material of the fluorine-containing inorganic compound is 0.1 sccm to 200 sccm, and the flow rate of the precursor material of the fluorine-containing polymer is 0.1 sccm to 200 sccm. The present application can control the content of the two materials in the total reflection film by controlling the flow rate of the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer introduced into the reaction chamber.

[0051] Those skilled in the art can adjust the molar content range of H element and O element by controlling the addition ratio and / or the flow rate of each precursor material of the fluorine-containing inorganic compound. Exemplarily, the precursor material of the fluorine-containing inorganic compound includes a metal source and a silicon source, and the metal source and the silicon source can be placed in a raw material pool, and the molar content range of H element and O element can be adjusted by adjusting the ratio of the metal source and the silicon source; or, the metal source and the silicon source can be placed in different raw material pools, and the molar content range of H element and O element can be adjusted by adjusting the flow rate of the metal source and the silicon source.

[0052] The present application has no particular restrictions on the method of regulating the film thickness of the total reflection film. For example, the thickness of the total reflection film generally increases with the increase of the CVD deposition time. Based on this, the present application can regulate the thickness of the total reflection film by regulating the reaction time of the reaction raw materials in the CVD device. Exemplarily, the thickness of the total reflection film of the present application can be regulated to be not less than 30nm, preferably 30nm to 200nm, by regulating the reaction time of the reaction raw materials in the CVD device.

[0053] In an optional embodiment, a silane coupling agent can also be introduced at the same time to further improve the adhesion performance of the total reflection film. The present application has no particular limitation on the silane coupling agent, for example, the silane coupling agent is selected from models such as KH550, KH560, KH570 or KH590.

[0054] The present application also provides a reflective device, the surface of which has the total reflection film described in any of the above embodiments.

[0055] In an optional embodiment, the material of the reflective device includes at least one of polyetherimide, polymethyl methacrylate, silicon, quartz glass and borosilicate glass. The above materials can be used as the substrate of the reflective device.

[0056] In an optional embodiment, the reflective device includes a prism. Figure 1 , Figure 1 This is a schematic diagram of the structure of a reflective device according to an embodiment of the present application. In the figure, the reflective device includes a reflective device body 1, and the surface of the reflective device body 1 has a total reflection film 2, and the total reflection film 2 can fully reflect light.

[0057] In an alternative embodiment, see Figure 1 The reflective device of the present application includes a prism. In addition, the reflective device of the present application may also include a plane reflector, an aspherical mirror, etc.

[0058] In an optional embodiment, the reflective device is immersed in the cooling liquid. The optical device with the total reflection film of the present application can maintain stable performance even if it is immersed in the cooling liquid for a long time, so that the reflective device has higher operating stability in the application scenario of the liquid cooling data center.

[0059] Example

[0060] The total reflection film and the preparation method thereof of the embodiment of the present application will be further described below in conjunction with more specific embodiments.

[0061] Example 1

[0062] N2 was introduced into the reaction chamber (film casting chamber) of the PECVD equipment, and the temperature of the reaction chamber was adjusted to 50°C and the pressure to 1 atm; the fluorine-containing inorganic compound MSiFH x O y The precursor material triethylaluminum is placed in the first raw material pool, hexamethyldisiloxane (HMDSO) is placed in the second raw material pool, and the precursor material hexafluoropropylene oxide dimer of the fluorinated polymer is placed in the third raw material pool. Then, the above three materials are introduced into the reaction chamber at the same time, and the flow rate of triethylaluminum is controlled to be 1sccm, and the flow rate of HMDSO is controlled to be 15sccm (i.e., MSiFH x O y The total flow rate of the precursor material is 16 sccm), and the flow rate of the fluorine-containing polymer precursor material is 4 sccm to regulate the MSiFH in the total reflection film. x O y and fluorine-containing polymer content; the above two materials are polymerized on the surface of the prism to be coated, and after reacting for 10 hours, a total reflection film with a thickness of 80nm is formed.

[0063] Embodiment 2~embodiment 3

[0064] In addition to regulating the fluorine-containing inorganic compound MSiFH according to Table 1 x O yThe flow rate of the precursor material and the flow rate of the fluorine-containing polymer precursor material are used to regulate the MSiFH in the total reflection film. x O y Except for the content of fluorine-containing polymer, the rest is the same as Example 1.

[0065] Embodiment 4~embodiment 5

[0066] Except for adjusting the reaction time according to Table 1 to adjust the thickness of the total reflection film, the rest is the same as Example 1.

[0067] Embodiment 6 to Embodiment 8

[0068] In addition to regulating the fluorine-containing inorganic compound MSiFH according to Table 2 x O y Except for the types of precursor materials and fluorine-containing polymer precursor, the rest is the same as Example 1.

[0069] Example 9

[0070] The process is the same as that of Example 1 except that the total reflection film prepared in Example 1 is immersed in hydrochloric acid with a mass concentration of 10% for 20 minutes to form a total reflection film with a porous structure.

[0071] Comparative Example 1

[0072] In addition to regulating the fluorine-containing inorganic compound MSiFH according to Table 1 x O y The flow rate of the precursor material and the flow rate of the fluorine-containing polymer precursor material are used to regulate the MSiFH in the total reflection film. x O y Except for the content of fluorine-containing polymer, the rest is the same as Example 1.

[0073] Test methods and equipment

[0074] Total reflection film adhesion test:

[0075] Adopt the 100-grid test method, use a utility knife to draw a 1mm*1mm cross and vertical small grid on the surface of the test area, each line should be deep enough to reach the substrate, stick 3M tape on the grid, and then press the tape on the lens with your fingers, let it stand for 1 minute, and then tear off the tape steadily at an angle as close to 45° as possible; judgment standard: 0 = ASTM grade 5B; the edge of the cut is completely smooth, and there is no peeling inside the grid for passing, otherwise it is unqualified.

[0076] Total reflection film refractive index test:

[0077] The refractive index of the total reflection film was tested by an Abbe refractometer (ATAGO model: NAR-1T SOLID).

[0078] Table 1 Preparation parameters of Examples 1 to 5 and Comparative Example 1

[0079]

[0080] Table 2 Preparation parameters of Example 1, Example 6 to Example 8

[0081]

[0082] Table 3 Performance data of various embodiments and comparative examples

[0083]

[0084] Combined with Table 3, it can be seen from Examples 1 to 9 and Comparative Example 1 that the total reflection film of the present application has good interface adhesion with the reflective device (such as a prism) and a low refractive index, and has excellent total reflection performance.

[0085] The content of the fluorine-containing inorganic compound, the content of the fluorine-containing polymer, and the thickness of the total reflection film usually also have an impact on the performance of the total reflection film. It can be seen from Examples 1, 4, and 5 that by adjusting the above parameters within the scope of this application, the total reflection film of the present application exhibits excellent interface adhesion performance and low reflectivity.

[0086] In the process of forming the total reflection film, the type of the precursor material of the fluorine-containing inorganic compound and the type of the fluorine-containing polymer precursor will usually also affect the performance of the total reflection film. It can be seen from Examples 1 and 6 to 8 that by adjusting the above parameters within the scope of this application, it is beneficial to obtain a total reflection film with excellent interface adhesion performance and low reflection performance.

[0087] It can also be seen from Example 1 and Example 9 that by soaking the total reflection film in acid solution, the refractive index of the total reflection film can be further reduced, which is beneficial to improving the total reflection performance of the total reflection film.

[0088] The above is a detailed introduction to a total reflection film and a preparation method thereof, a reflective device and a preparation method thereof disclosed in the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core inventions of the embodiments of the present application. At the same time, for general technicians in this field, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A total reflection film, characterized in that: The total reflection film comprises a fluorine-containing inorganic compound and a fluorine-containing polymer, wherein the mass percentage of the fluorine-containing inorganic compound in the total reflection film is m1, and the mass percentage of the fluorine-containing polymer in the total reflection film is m2, 80%≤m1<100%, 0%<m2≤20%; the fluorine-containing inorganic compound has a chemical formula of MSiFH x O y , wherein M includes aluminum and magnesium, 0<x≤0.5, 1.5≤y≤2.0, and the total reflection film is obtained based on PECVD.

2. The total reflection film according to claim 1, characterized in that: The working wavelength of the total reflection film is not less than 850nm.

3. The total reflection film according to claim 2, characterized in that: The working wavelength of the total reflection film is 1250 nm~2000 nm.

4. The total reflection film according to claim 1, characterized in that: The thickness of the total reflection film is 30nm~200nm.

5. The total reflection film according to claim 1, characterized in that: The total reflection film has a porous structure.

6. The total reflection film according to claim 1, characterized in that: The refractive index of the total reflection film is 1.03-1.

23.

7. The total reflection film according to claim 1, characterized in that: The fluorine-containing polymer includes at least one of a fluorine-containing epoxy compound and a fluorine-containing acrylate compound.

8. A method for preparing a total reflection film according to any one of claims 1 to 7, characterized in that: The following steps are involved: The precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are introduced into the reaction chamber of the CVD equipment with an inert gas atmosphere, so that the precursor material of the fluorine-containing inorganic compound and the precursor material of the fluorine-containing polymer are polymerized on the surface of the reflective device to be coated to form the total reflection film.

9. The preparation method according to claim 8, characterized in that: The precursor material of the fluorine-containing inorganic compound includes a metal source and a silicon source, the metal source includes at least one of triethylaluminum, triethoxide aluminum and isopropoxide aluminum, the silicon source includes at least one of hexamethyldisiloxane, tetramethyldisiloxane and octamethylcyclotetrasiloxane, and the precursor material of the fluorine-containing polymer includes at least one of hexafluoropropylene oxide dimer, hexafluoropropylene oxide and perfluoroacrylate.

10. The preparation method according to claim 9, characterized in that: The metal source also includes at least one of dimethyl magnesium and diethyl magnesium.

11. The preparation method according to claim 8, characterized in that: The temperature of the reaction chamber is 25° C. to 60° C., and the inert gas is nitrogen or helium.

12. The preparation method according to claim 8, characterized in that: The method further comprises: The coated reflective device is immersed in an acid solution for 15 to 30 minutes to form a total reflective film with a porous structure.

13. A reflective device, characterized in that: The surface of the reflective device has the total reflection film according to any one of claims 1 to 7.

14. The reflective device according to claim 13, characterized in that: The material of the reflective device includes at least one of polyetherimide, polymethyl methacrylate, silicon, quartz glass and borosilicate glass.

15. The reflective device according to claim 13, characterized in that: The light reflecting device includes a prism.

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