Diamond film and preparation method thereof

Abstract

The embodiment of the invention provides a preparation method of a diamond film. The preparation method comprises the following steps that an organic molecule source is heated, and organic molecules are evaporated into a reaction cavity; the organic molecules in the reaction cavity are cracked through microwaves to form hydrocarbon free radicals; and depositing the hydrocarbon free radicals on a high-temperature substrate for nucleation so as to grow and form the diamond film. According to the preparation method of the diamond film provided by the embodiment of the invention, the solid organic molecules are used as the carbon source, and the diamond is grown through the microwave plasma technology, so that the preparation process is simplified and the cost is reduced while the excellent performance of the diamond is maintained. The embodiment of the invention further provides the diamond film.

Description

Technical Field

[0001] This application belongs to the technical field of material manufacturing, and particularly relates to a diamond film and a preparation method thereof. Background Art

[0002] Due to its excellent physical and chemical properties, such as extremely high hardness, high thermal conductivity, excellent electrical insulation, and chemical stability, diamond has a wide range of applications in industries, electronics, optics, and jewelry. However, natural diamond resources are limited and costly, so the technology of artificial diamond synthesis has become a research hotspot.

[0003] Currently, the main methods for artificial diamond synthesis include the high-pressure high-temperature method (HPHT) and the chemical vapor deposition method (CVD). The high-pressure high-temperature method requires extremely high pressure and temperature, with complex equipment and high costs; although the chemical vapor deposition method can be carried out at lower pressure, the growth rate is slow and the requirements for substrate materials are high. Summary of the Invention

[0004] In view of the problems existing in the above related technologies, the present invention provides a diamond film and a preparation method thereof, which use solid organic molecules as carbon sources and grow diamonds through microwave plasma technology, so as to simplify the preparation process and reduce costs while maintaining the excellent properties of diamonds.

[0005] In a first aspect, an embodiment of the present application provides a method for preparing a diamond film, including the following steps:

[0006] Heating an organic molecular source and evaporating the organic molecules into the reaction chamber;

[0007] Cracking the organic molecules in the reaction chamber through microwaves to form hydrocarbon radicals; and

[0008] Depositing the hydrocarbon radicals onto a high-temperature substrate for nucleation to grow and form a diamond film.

[0009] Further, after depositing the hydrocarbon radicals onto a high-temperature substrate for nucleation to grow and form a diamond film, it further includes:

[0010] Cooling the diamond film to stabilize the diamond film.

[0011] Further, the cooling the diamond film to stabilize the diamond film includes:

[0012] Quickly cooling the diamond film through cooling circulating water to stabilize the diamond film.

[0013] Further, the heating an organic molecular source and evaporating the organic molecules into the reaction chamber includes:

[0014] Use a k-cell molecular beam evaporation source to heat the organic molecular source and evaporate the organic molecules into the reaction chamber.

[0015] Further, the frequency of the microwave is 2.45 GHz.

[0016] Further, the frequency of the microwave is 915 MHz.

[0017] Further, the heating temperature of the substrate is between 800 °C and 900 °C.

[0018] Further, the organic molecular source includes, but is not limited to, pentacene, hexabenzocoronene, rubrene, and PTCDA.

[0019] Further, the substrate is diamond, silicon, or graphite.

[0020] In a second aspect, an embodiment of the present application provides a diamond film, which is made by the method described in any one of the above.

[0021] In the method for preparing a diamond film provided by the embodiment of the present application, first, the organic molecular source is heated to the evaporation temperature by a heating device, so that the organic molecules enter the reaction chamber in a gaseous form. Subsequently, the organic molecules are cracked in the reaction chamber by using microwave energy to form hydrocarbon radicals. These radicals are the key precursors for the growth of the diamond film. In the growth stage of the diamond film, the hydrocarbon radicals are guided to a high-temperature substrate. The high-temperature substrate provides the appropriate temperature and surface conditions required for the growth of the diamond film. On the substrate, the hydrocarbon radicals adsorb, nucleate, and gradually grow to form a continuous diamond film. This process is not only efficient but also can ensure the quality and uniformity of the diamond film. The method for preparing a diamond film provided by the embodiment of the present application has the advantages of simple process, easy control, strong adaptability, low preparation cost, etc., providing strong support for the wide application of diamond films. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for the description of the embodiments or related technologies. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0023] Figure 1 It is a schematic flow chart of the method for preparing a diamond film provided by the embodiment of the present application;

[0024] Figure 2 It is a schematic structural diagram of the preparation equipment used in the method for preparing a diamond film provided by the embodiment of the present application.

[0025] The realization, functional features and advantages of the present application will be further described in conjunction with the embodiments with reference to the accompanying drawings. Specific Embodiments

[0026] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0027] It should be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0028] It should also be understood that the terms used in this specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in this specification of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present application according to specific circumstances.

[0029] Referring to Figure 1 and Figure 2 , an embodiment of the present application provides a method for preparing a diamond film, including the following steps:

[0030] S101: Heating an organic molecular source and evaporating the organic molecules into a reaction chamber;

[0031] S102: Cracking the organic molecules in the reaction chamber by microwaves to form hydrocarbon radicals; and

[0032] S103: Depositing the hydrocarbon radicals on a high-temperature substrate to nucleate and grow to form a diamond film.

[0033] In the method for preparing a diamond film provided by an embodiment of the present application, first, an organic molecular source is heated to the evaporation temperature by a heating device, so that the organic molecules enter the reaction chamber in a gaseous form. Subsequently, the organic molecules are cracked in the reaction chamber by using microwave energy to form hydrocarbon radicals. These radicals are the key precursors for the growth of the diamond film. In the growth stage of the diamond film, the hydrocarbon radicals are guided to a high-temperature substrate. The high-temperature substrate provides the appropriate temperature and surface conditions required for the growth of the diamond film. On the substrate, the hydrocarbon radicals adsorb, nucleate, and gradually grow to form a continuous diamond film. This process is not only efficient but also can ensure the quality and uniformity of the diamond film.

[0034] The method for preparing a diamond film provided by an embodiment of the present application has the following remarkable advantages: First, the microwave cracking technology improves the cracking efficiency and purity of the organic molecules, thereby ensuring the high quality of the diamond film. Second, the application of the high-temperature substrate helps to stably form the diamond phase, further improving the performance of the diamond film. Finally, by selecting a suitable organic molecular source, the composition and structure of the diamond film can be regulated to meet the requirements of different application fields.

[0035] In summary, the method for preparing a diamond film provided by an embodiment of the present application has the advantages of simple process, easy control, strong adaptability, low preparation cost, etc., providing strong support for the wide application of diamond films.

[0036] Refer to Figure 2 The preparation equipment adopted by the method for preparing a diamond film provided by an embodiment of the present application includes a microwave generator, a waveguide, a reaction chamber, an organic molecular source inlet channel, a sample stage, a cooling system, and a control system. Among them, the organic molecular source enables the organic molecules to evaporate into the reaction chamber through the organic molecular source inlet channel. The microwave generator generates microwave energy and transmits it to the reaction chamber through the waveguide, so that the organic molecules in the reaction chamber are cracked to form hydrocarbon radicals. A sample stage is provided in the reaction chamber for placing the substrate, and the hydrocarbon radicals are deposited on the high-temperature substrate to nucleate and grow to form a diamond film. The cooling system is used to rapidly cool the sample, and the control system is used to adjust the microwave frequency, temperature, and reaction time.

[0037] Further, in some embodiments of the present application, after the hydrocarbon radicals are deposited on the high-temperature substrate to nucleate and grow to form a diamond film, it further includes:

[0038] Cool the diamond film to stabilize the diamond film.

[0039] Specifically, after the growth of the diamond film is completed, in order to ensure the stability of its structure and the durability of its performance, a cooling process is also required. The cooling process is achieved through appropriate cooling equipment, which can effectively reduce the temperature of the diamond film, stabilize its crystal structure, and prevent structural deformation or performance degradation caused by high temperature.

[0040] Furthermore, in some embodiments of the present application, cooling the diamond film to stabilize the diamond film includes:

[0041] Rapidly cooling the diamond film through cooling circulating water to stabilize the diamond film.

[0042] Specifically, after the reaction ends, the diamond film is rapidly cooled through a cooling circulating water system. Rapid cooling helps to stabilize the structure of the diamond film and prevent film cracking or peeling caused by sudden temperature changes. During the cooling process, the water temperature should be controlled within an appropriate range to ensure the quality of the diamond film.

[0043] In addition, the cooled diamond film can be further post-processed, such as surface polishing, cutting, or doping treatment, to meet the requirements of different applications. For example, doping with boron or nitrogen can change the electrical properties of the diamond film and make it suitable for electronic devices or sensors.

[0044] Furthermore, in some embodiments of the present application, heating the organic molecular source and evaporating the organic molecules into the reaction chamber includes:

[0045] Using a k-cell molecular beam evaporation source to heat the organic molecular source and evaporate the organic molecules into the reaction chamber.

[0046] Specifically, the organic molecular source is heated by a k-cell molecular beam evaporation source, and the organic molecules are evaporated into the reaction chamber in the form of a molecular beam. The k-cell molecular beam evaporation source ensures the effective evaporation of organic molecules and the smooth progress of subsequent reactions with its characteristics of high precision, high stability, and high purity.

[0047] Furthermore, in some embodiments of the present application, the frequency of the microwave is 2.45 GHz.

[0048] Specifically, microwaves are generated by a microwave generator, and the frequency of the microwaves can be selected as 2.45 GHz. The microwave energy cleaves the organic molecules to form hydrocarbon radicals, and the hydrocarbon radicals deposit on the high-temperature substrate to nucleate and grow to form a diamond film.

[0049] Furthermore, the frequency of the microwave is 915 MHz.

[0050] Specifically, microwaves are generated by a microwave generator, and the frequency of the microwaves can be selected as 915 MHz to adapt to different cavity sizes and power requirements. The microwave energy cleaves organic molecules to form hydrocarbon radicals, and the hydrocarbon radicals deposit on a high-temperature substrate to nucleate and grow to form a diamond film.

[0051] Furthermore, in some embodiments of the present application, the heating temperature of the substrate is between 800 °C and 900 °C.

[0052] Specifically, the processed substrate is heated to a temperature between 800 °C and 900 °C, and this temperature range has been proven to be one of the optimal conditions for diamond film growth. At this temperature, hydrocarbon radicals are guided to the substrate, start to adsorb, nucleate, and gradually grow to form a continuous diamond film. The high-temperature substrate not only provides a suitable temperature environment for the growth of the diamond film but also helps the stable formation of the diamond phase, ensuring the high quality and uniformity of the diamond film.

[0053] Furthermore, in some embodiments of the present application, the organic molecular source includes but is not limited to pentacene, hexabenzocoronene, rubrene, and PTCDA (3,4,9,10-Perylenetetracarboxylic Dianhydride).

[0054] Introducing organic molecular sources such as pentacene, hexabenzocoronene, rubrene, and PTCDA into the preparation method of diamond films not only enriches the selection range of carbon sources but also may provide unique advantages and properties for the growth of diamond films.

[0055] Furthermore, in some embodiments of the present application, the substrate is diamond, silicon, or graphite.

[0056] Specifically, when selecting diamond, silicon, or graphite as the substrate material, factors such as the growth conditions of the diamond film, application fields, and costs need to be considered. Diamond substrates are suitable for application scenarios that require high-quality diamond films with low defect density; silicon substrates are suitable for application scenarios that require cost reduction and compatibility with semiconductor processes; graphite substrates are suitable for application scenarios that require high electrical conductivity and good mechanical properties.

[0057] In addition, different substrate materials may affect the growth rate, crystal structure, and properties of the diamond film. Therefore, in practical applications, it is necessary to select a suitable substrate material according to specific experimental conditions and requirements and optimize the growth parameters to obtain the best diamond film performance.

[0058] In addition, an embodiment of the present application further provides a diamond film, which is made by the method described in any one of the above. For the specific preparation method of this diamond film, refer to the above embodiments. Since the specific preparation method of the diamond film adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here one by one.

[0059] As described above, the above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present application, and these modifications or substitutions should be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for preparing a diamond film, characterized in that, Comprising the following steps: Heating an organic molecular source and causing the organic molecules to evaporate into the reaction chamber; Cracking the organic molecules in the reaction chamber by microwaves to form hydrocarbon radicals; and Nucleating the hydrocarbon radicals deposited on a high-temperature substrate to grow and form a diamond film.

2. The method according to claim 1, wherein After the hydrocarbon radicals are deposited on the high-temperature substrate to nucleate and grow to form a diamond film, it further includes: Cooling the diamond film to stabilize the diamond film.

3. The method according to claim 2, characterized in that The cooling the diamond film to stabilize the diamond film includes: Rapidly cooling the diamond film by circulating cooling water to stabilize the diamond film.

4. The method according to claim 1, wherein The heating the organic molecular source and causing the organic molecules to evaporate into the reaction chamber includes: Using a k-cell molecular beam evaporation source to heat the organic molecular source and cause the organic molecules to evaporate into the reaction chamber.

5. The method according to claim 1, characterized in that, The frequency of the microwaves is 2.45 GHz.

6. The method according to claim 1, characterized in that, The frequency of the microwaves is 915 MHz.

7. The method according to claim 1, wherein The heating temperature of the substrate is between 800 °C and 900 °C.

8. The method according to claim 1, characterized in that, The organic molecular source includes but is not limited to pentacene, hexabenzocoronene, rubrene, and PTCDA.

9. The method according to claim 1, characterized in that The substrate is diamond, silicon, or graphite.

10. A diamond film, characterized in that, The diamond film is made by the method according to any one of claims 1 to 9.

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