Method for preparing patterned diamond and patterned diamond semiconductor material
By combining laser ablation and vapor deposition, the problems of mechanical damage to the substrate and poor cost-effectiveness and flexibility in the existing technology are solved, and high-quality patterned diamond preparation is achieved to meet different usage requirements.
Patent Information
- Application Number
- CN202510677388.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-23
- Publication Date
- 2025-09-19
AI Technical Summary
In the existing technology for preparing diamond semiconductor materials, mechanical grinding causes damage to the substrate, the photolithography-etching process is costly and inflexible, the chemical vapor deposition method cannot selectively grow patterned diamonds, and the nanoimprinting equipment is expensive and complex, making large-scale processing difficult.
A highly controllable laser ablation process is used to prepare patterned grooves on the substrate, diamond nanoparticle dispersion is sprayed and patterned diamond is formed by vapor deposition, and a flexible mask and laser ablation are used to reduce mechanical damage and achieve non-contact processing.
The quality and uniformity of patterned diamonds are improved, substrate damage is reduced, preparation costs are lowered, and flexible patterning processing is achieved to adapt to different usage objectives.
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Figure CN120666308A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor material technology, and in particular, to a method for preparing patterned diamond and imaged diamond semiconductor materials. Background Art
[0002] Diamond is a new type of semiconductor material with characteristics such as wide bandgap, high carrier mobility, large carrier saturation drift velocity, high chemical stability, large critical breakdown field strength, high thermal conductivity and excellent optical properties. It is an ideal material for manufacturing high-frequency, high-power, low-power electronic devices, and has great application potential in thermal management, power electronics, communications, optics, quantum information and other fields.
[0003] It should be noted that the above statements are only used to provide background technical information related to this application and do not necessarily constitute prior art. Summary of the Invention
[0004] In a first aspect of the present application, a method for preparing patterned diamond is proposed, comprising: providing a substrate having a mask provided on at least one side; performing patterned laser ablation on the mask to penetrate the mask and prepare a patterned groove on the substrate, wherein the depth of the patterned groove is 0.2 μm-3 μm; spraying a diamond nanoparticle dispersion into the patterned groove to prepare diamond nuclei; mechanically removing the mask, introducing hydrogen and methane, and performing vapor deposition on the diamond nuclei to prepare the patterned diamond.
[0005] The method for producing patterned diamonds proposed in this application utilizes highly controllable, non-contact laser processing to process the substrate surface and mask, minimizing mechanical damage to the substrate and other components on it during the production process. Furthermore, this method is easily controllable and provides excellent processing uniformity, which contributes to improving the quality of the resulting patterned diamonds.
[0006] In some embodiments, the diamond nanoparticles in the diamond nanoparticle dispersant have a Dv50 particle size of 5 nm to 10 nm. Diamond particles with a Dv50 particle size within this range generate high-frequency collisions with the substrate's microstructure during nucleation, thereby promoting van der Waals bonding at the interface between the diamond particles and the substrate.
[0007] In some embodiments, the laser ablation process uses a laser wavelength ranging from 1000 nm to 1100 nm, a laser power ranging from 80 μJ to 160 μJ per pulse, and a laser scanning speed ranging from 100 mm / s to 300 mm / s. Laser ablation laser wavelength, power, and scanning speed within the aforementioned ranges can directly affect the microstructure and roughness of the substrate surface after laser ablation. This can help improve the density of diamond nuclei produced and the bonding strength after growth.
[0008] In some embodiments, the mass-to-volume ratio of diamond nanoparticles to solvent in the diamond nanoparticle dispersant is 5 mg / mL to 10 mg / mL. When the diamond particle concentration in the diamond nanoparticle dispersant is within the aforementioned range, diamond nucleation exhibits strong selectivity, which helps reduce the formation time of diamond nuclei and increase the density of diamond nuclei. This helps improve the quality of the patterned diamond semiconductor material grown.
[0009] In some embodiments, the mask comprises at least one of polyimide, polyacrylonitrile, and polyamide-imide. The materials of the aforementioned masks have excellent stability at room temperature, are easily removed by laser ablation, and are flexible enough to be attached to a substrate as a mask.
[0010] In some embodiments, during the vapor deposition process, the hydrogen flow rate is 150 sccm-200 sccm, the methane flow rate is 10 sccm-15 sccm, and the vapor deposition process time is 1 hour-5 hours. The ratio and size of the hydrogen and methane flow rates during the vapor deposition process within the aforementioned range are beneficial to improving the purity and growth rate of the prepared diamond. The process time within the aforementioned range is beneficial to improving the thickness and stress of the prepared diamond, forming a continuous and uniform thin film of patterned diamond, thereby reducing stress in the prepared patterned diamond and reducing defects such as shedding and fracture of the patterned diamond.
[0011] In some embodiments, the microwave power of the vapor deposition process is 4000W-5000W, and the pressure of the vapor deposition process is 150mbar-180mbar. The power and pressure of the vapor deposition process within the aforementioned ranges facilitate control of the orientation of the patterned diamond produced during the preparation process, thereby improving heat dissipation performance and reducing the generation of graphite phase impurities.
[0012] In some embodiments, the substrate is made of at least one of single crystal silicon, gallium arsenide, and gallium nitride.
[0013] In some embodiments, the solvent in the diamond nanoparticle dispersant includes at least one of H2O, ethylene glycol, and ethanol. The solvent is selected within the aforementioned range and has advantages such as low cost, chemical stability, and minimal harm to the human body. Furthermore, the selected solvent exhibits good adsorption properties to the substrate, thereby facilitating the formation of patterned diamonds on the substrate surface.
[0014] In a second aspect of the present application, the present application proposes an imaged diamond semiconductor material, which is prepared using the method proposed in the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0016] Figure 1 A schematic diagram of the process of preparing patterned diamond proposed in this application;
[0017] Figure 2 This is a photograph of a patterned groove surface prepared by laser ablation in one embodiment of the present application;
[0018] Figure 3 This is a photograph of a cross section of a patterned groove prepared by laser ablation in one embodiment of the present application;
[0019] Figure 4 This is a photograph of a patterned diamond prepared in one example of the present application.
[0020] Description of reference numerals:
[0021] Substrate 1; mask 2; diamond nanoparticles 3; patterned diamond 4. DETAILED DESCRIPTION
[0022] The following describes the embodiments of the present application in detail. Examples of the embodiments are shown in the accompanying drawings, but unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of substantially identical structures may be omitted. This is to avoid unnecessary lengthiness in the following description and to facilitate understanding by those skilled in the art. In addition, the drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.
[0023] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application; unless otherwise specified, the numerical values of the various parameters mentioned in this application can be measured using various measurement methods commonly used in the art (for example, they can be tested according to the methods given in the embodiments of this application).
[0024] The terms "include" and "have" in the description and claims of this application and any variations thereof are open expressions, that is, including the contents specified in this application but not excluding other contents.
[0025] In the description of this application, regardless of whether the word "about" or "approximately" is used, all numbers disclosed herein are approximate values. The value of each number may vary by less than 10% or by a reasonable difference considered by a person skilled in the art, such as 1%, 2%, 3%, 4% or 5%.
[0026] " range " disclosed in the present application is limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and can be arbitrarily combined, that is, any lower limit can form a range with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range value 1 and 2 are listed, and if the maximum range value 3,4 and 5 are listed, then the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.
[0027] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.
[0028] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.
[0029] In the related art, the main methods for preparing diamonds are high temperature and high pressure method and chemical vapor deposition method. Among them, chemical vapor deposition method is the main way to achieve the growth of high-quality diamond semiconductor materials. Before using chemical vapor deposition method to grow diamonds, it is often necessary to use mechanical grinding to treat diamond nanoparticles on the surface of the substrate so that they form a microstructure on the surface of the substrate to promote the nucleation of diamond nanoparticles. However, the surface microstructure formed by mechanical grinding has the problem of being difficult to control and having poor uniformity, which affects the growth quality of the diamond film. Moreover, mechanical grinding is a contact grinding of the entire substrate wafer, which is difficult to process selectively and regionally. Therefore, mechanical damage will be caused to the substrate or the components prepared thereon during the grinding process.
[0030] In addition, diamonds usually need to be patterned when used in semiconductor devices. Chemical vapor deposition cannot selectively grow patterned diamonds. In the prior art, diamond patterning is mainly achieved by photolithography-etching process. Although the photolithography-etching process can accurately achieve patterned diamonds, the expensive photolithography and etching equipment and cumbersome process steps cause the existing diamond patterning process to have problems of high cost and low efficiency. In addition, nanoimprinting can also be used to achieve patterned porous diamonds. However, this technical method requires specially customized templates, poor processing flexibility, and the imprinting process equipment is expensive, the process is complicated, and large-scale processing cannot be performed.
[0031] The method for producing patterned diamonds proposed in this application utilizes highly controllable, non-contact laser processing to process the substrate surface and mask, minimizing mechanical damage to the substrate and other components on it during the production process. Furthermore, this method is easily controllable and provides excellent processing uniformity, which contributes to improving the quality of the resulting patterned diamonds.
[0032] In a first aspect of the present application, a method for preparing patterned diamond is proposed, comprising: providing a substrate having a mask provided on at least one side; performing patterned laser ablation on the mask to penetrate the mask and prepare a patterned groove on the substrate, wherein the depth of the patterned groove is 0.2 μm-3 μm; spraying a diamond nanoparticle dispersion into the patterned groove to prepare diamond nuclei; mechanically removing the mask, introducing hydrogen and methane, and performing vapor deposition on the diamond nuclei to prepare the patterned diamond.
[0033] The method proposed in this application refers to Figure 1 , by setting a mask 2 on the substrate 1, including attaching a flexible mask. Laser ablation is used to remove the mask 2 in the area where diamond is to be grown, and a patterned structure is constructed at the micron level. At the same time, a patterned groove with a microstructure is processed on the surface of the substrate 1. The morphology of the patterned groove can be referred to Figure 2 、 Figure 3 A diamond nanoparticle dispersion is sprayed into the patterned grooves. The remaining mask on substrate 1 provides a shielding effect, ensuring that diamond nanoparticles 3 are only filled in the shallow grooves with microstructures during diamond nucleation. Furthermore, patterned diamond 4 is grown via vapor phase chemical deposition, ensuring that patterned diamond grows only in the patterned grooves during the diamond nucleation process, thereby achieving the production of patterned diamond.
[0034] Therefore, through laser ablation processing, a patterned groove with a uniform microstructure on the inner surface can be prepared on the substrate while penetrating the mask. The nanoscale microstructure thereon can promote the uniformity and stability of diamond nucleation, thereby obtaining high-quality patterned diamonds consistent with the nucleation window pattern defined by the patterned groove during the diamond growth process by vapor phase chemical deposition.
[0035] In some embodiments, the diamond nanoparticles in the diamond nanoparticle dispersant have a Dv50 particle size of 5 nm to 10 nm. Diamond particles with a Dv50 particle size within this range generate high-frequency collisions with the substrate's microstructure during nucleation, thereby promoting van der Waals bonding at the interface between the diamond particles and the substrate.
[0036] In some embodiments, the laser ablation process uses a laser wavelength ranging from 1000 nm to 1100 nm, a laser power ranging from 80 μJ to 160 μJ per pulse, and a laser scanning speed ranging from 100 mm / s to 300 mm / s. Laser ablation laser wavelength, power, and scanning speed within the aforementioned ranges can directly affect the microstructure and roughness of the substrate surface after laser ablation. This can help improve the density of diamond nuclei produced and the bonding strength after growth.
[0037] In some embodiments, the mass-to-volume ratio of diamond nanoparticles to solvent in the diamond nanoparticle dispersant is 5 mg / mL to 10 mg / mL. When the diamond particle concentration in the diamond nanoparticle dispersant is within the aforementioned range, diamond nucleation exhibits strong selectivity, which helps reduce the formation time of diamond nuclei and increase the density of diamond nuclei. This helps improve the quality of the patterned diamond semiconductor material grown.
[0038] In some embodiments, the mask comprises at least one of polyimide, polyacrylonitrile, and polyamide-imide. The materials of the aforementioned masks have excellent stability at room temperature, are easily removed by laser ablation, and are flexible enough to be attached to a substrate as a mask.
[0039] In some embodiments, during the vapor deposition process, the flow rate of hydrogen is 150 sccm-200 sccm, the flow rate of methane is 10 sccm-15 sccm, and the time of the vapor deposition process is 1 hour-5 hours.
[0040] In some embodiments, the microwave power of the vapor deposition process is 4000W-5000W, and the pressure of the vapor deposition process is 150mbar-180mbar. The ratio and size of the hydrogen and methane flow rates in the vapor deposition process within the aforementioned ranges are beneficial for improving the purity and growth rate of the prepared diamond. The treatment time within the aforementioned ranges is beneficial for improving the thickness and stress of the prepared diamond, forming a continuous and uniform thin film of patterned diamond, thereby reducing stress in the prepared patterned diamond and reducing defects such as shedding and fracture of the patterned diamond.
[0041] In some embodiments, the substrate is made of at least one of single crystal silicon, gallium arsenide, and gallium nitride.
[0042] In some embodiments, the solvent in the diamond nanoparticle dispersant includes at least one of H2O, ethylene glycol, and ethanol. The power and pressure of the vapor deposition process are within the aforementioned ranges, which facilitates control of the orientation of the patterned diamonds produced during the preparation process, thereby improving heat dissipation and reducing the generation of graphite phase impurities.
[0043] In a second aspect of the present application, a patterned diamond semiconductor material is provided, which is prepared using the method provided in the present application. The pattern of the patterned diamond semiconductor material has a flexible variation space, which is conducive to adapting to the needs of different application targets.
[0044] The present invention will be described below by way of specific examples. It should be noted that the following examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. Where specific techniques or conditions are not specified in the examples, they are determined according to the techniques or conditions described in the literature in this area or according to the product specifications. Reagents or instruments not specified by manufacturer are all commercially available conventional products.
[0045] Example 1
[0046] 1) A 4-inch silicon wafer with a thickness of 350 μm was used as a substrate, cleaned and dried, and a 25 μm thick semiconductor polyimide film was attached to the surface as a mask;
[0047] 2) Using a wavelength of 1064nm and an energy density of 0.51J / cm 2An infrared laser with a scanning speed of 200 mm / s and a scanning pitch of 10 μm scans the mask according to the designed processing path to perform laser ablation to remove the polyimide film. While removing the polyimide film on the scanning path, a 1 μm deep patterned groove with a microstructure is also processed on the surface of the silicon substrate.
[0048] 3) A dispersion containing diamond nanoparticles with a particle diameter of 3 nm is sprayed into the diamond nucleation window by a spraying process and dried so that the diamond nanoparticles are densely filled in the shallow grooves on the surface of the silicon substrate to prepare diamond nuclei.
[0049] 4) Mechanically remove the residual polyimide film on the surface of the silicon substrate.
[0050] 5) The silicon substrate with diamond nuclei prepared and the polyimide film removed was placed in a microwave plasma vapor deposition system, and diamond growth was carried out for 2 hours under the process parameters of hydrogen flow rate 200 sccm, methane flow rate 12 sccm, microwave power 4500 W, and pressure 170 mbar. A patterned diamond film with a thickness of 10 μm was obtained in the shallow grooves on the surface of the silicon substrate, as shown in FIG. Figure 4 shown. Figure 4 The prepared patterned diamond has good continuity and density, and has a high bonding strength with the substrate and is not easy to fall off. The diamond particle size in the middle area of the microgroove is larger, indicating that there are relatively few defects.
[0051] In the description of the present application, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact with each other, or the first and second features being in contact with each other not directly but via another feature therebetween.
[0052] In the description of this application, a first feature “on”, “above” and “above” a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.
[0053] In the description of this application, "A and / or B" may include the case of A alone, the case of B alone, or any of the cases of A and B, where A and B are only used for example, and may be any technical feature connected by "and / or" in this application.
[0054] In this application, the writing order of each step does not mean a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of this application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or steps (b) and (a) performed sequentially. For example, it is mentioned that the method may also include step (c), indicating that step (c) can be added to the method in any order. For example, the method may include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.
[0055] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.
Claims
1. A method for preparing patterned diamond, characterized in that: include: providing a substrate having a mask disposed on at least one side; Performing patterned laser ablation on the mask to penetrate the mask and form a patterned groove on the substrate, wherein the depth of the patterned groove is 0.2 μm-3 μm; spraying a diamond nanoparticle dispersion into the patterned groove to prepare diamond nuclei; The mask is mechanically removed, hydrogen and methane are introduced, and the diamond nuclei are vapor-deposited to prepare the patterned diamond.
2. The method according to claim 1, characterized in that In the diamond nanoparticle dispersant, the Dv50 particle size of the diamond nanoparticles is 5 nm to 10 nm.
3. The method according to claim 1, characterized in that The laser wavelength range of the laser ablation treatment is 1000nm-1100nm, the laser power of the laser ablation treatment is 80μJ-160μJ per single pulse, and the scanning speed of the laser ablation treatment is 100mm / s-300mm / s.
4. The method according to claim 1, wherein In the diamond nanoparticle dispersant, the mass volume ratio of the diamond nanoparticles to the solvent is 5 mg / mL-10 mg / mL.
5. The method according to claim 1, wherein The mask includes at least one of polyimide, polyacrylonitrile, and polyamide-imide.
6. The method according to any one of claims 1 to 5, characterized in that During the vapor deposition process, the flow rate of the hydrogen is 150 sccm-200 sccm, the flow rate of the methane is 10 sccm-15 sccm, and the time of the vapor deposition process is 1 hour-5 hours.
7. The method according to any one of claims 1 to 5, characterized in that The microwave power of the vapor deposition process is 4000W-5000W, and the pressure of the vapor deposition process is 150mbar-180mbar.
8. The method according to any one of claims 1 to 5, characterized in that The material of the substrate includes at least one of single crystal silicon, gallium arsenide, and gallium nitride.
9. The method according to any one of claims 1 to 5, characterized in that In the diamond nanoparticle dispersant, the solvent includes at least one of H2O, ethylene glycol, and ethanol.
10. A patterned diamond semiconductor material, characterized in that: The method according to any one of claims 1 to 9 is used for preparation.