Boron carbide composite ceramic material, method of making and etching components
By pre-sintering and hot-pressing boron carbide, titanium boride, and silicon carbide particles, a dense and uniform boron carbide composite ceramic material is formed, which solves the problem of poor density of traditional boron carbide ceramics and improves its etching resistance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA HUBEI LONGZHONG LABORATORY
- Filing Date
- 2026-05-22
- Publication Date
- 2026-06-23
Smart Images
Figure CN122254891A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of ceramic materials technology, and in particular to boron carbide composite ceramic materials, their preparation methods, and etching components. Background Technology
[0002] In the chip fabrication process of electronic materials, etching equipment is required to etch wafers. Therefore, components such as the cavity, ESC (Electrostatic Chuck), and focusing ring of the etching equipment must meet etching resistance requirements. Traditionally, etching-resistant materials such as alumina or silicon carbide are used to fabricate the internal components of the etching equipment. Among these, chemical vapor deposition of silicon carbide exhibits good etching resistance, but its fabrication process is complex and costly. Boron carbide ceramics possess high hardness, high wear resistance, and impact resistance; however, pure boron carbide ceramics have poor density, making it difficult to meet the etching requirements of etching equipment. Therefore, how to provide a boron carbide ceramic with good etching resistance has become an urgent technical problem to be solved. Summary of the Invention
[0003] Therefore, it is necessary to provide a boron carbide composite ceramic material with good resistance to plasma etching, its preparation method, and the etching component thereof.
[0004] In a first aspect, this application provides a method for preparing a boron carbide composite ceramic material, the method comprising:
[0005] The particles contain boron carbide, titanium boride, and silicon carbide. The particles have a spherical structure and contain boron carbide at a mass ratio of 70% to 90%, titanium boride at a mass ratio of 5% to 25%, and silicon carbide at a mass ratio of 5% to 25%.
[0006] Boron carbide composite ceramic materials were prepared by pre-sintering and hot-pressing the particulate matter sequentially; the pre-sintering temperature was 1200℃~1500℃.
[0007] In some embodiments, the preparation method also satisfies at least one of the following conditions:
[0008] (1) The sphericity of the particles is 0.85~1, and the volume average particle size Dv50 is 50μm~200μm;
[0009] (2) The holding time for pre-sintering is 3h~5h, the heating rate is 1℃ / min~3℃ / min, and the atmosphere is a protective atmosphere or a hydrogen-containing atmosphere.
[0010] (3) The temperature of hot pressing sintering is 1800℃~2000℃, the pressure is 30MPa~50MPa, the holding time is 0.5h~2h, the heating rate is 3℃ / min~5℃ / min, and the vacuum degree is less than 0.01Pa.
[0011] In some embodiments, the method of forming particulate matter includes:
[0012] A slurry containing boron carbide, titanium boride, silicon carbide and a binder is prepared and granulated to form preformed particles;
[0013] Pre-formed granules are prepared by debinding them.
[0014] In some embodiments, the slurry has a solid content of 40% to 60% and a viscosity of 300 cps to 500 cps.
[0015] In some embodiments, the slurry satisfies at least one of the following conditions:
[0016] (1) The slurry is formed by ball milling; the ball-to-material ratio of the ball mill is (4~6):1, the rotation speed is 250rpm~300rpm, and the time is 10h~15h;
[0017] (2) The slurry contains 1% to 3% of the total mass of boron carbide, titanium boride, and silicon carbide as binder;
[0018] (3) The slurry also contains a dispersant, the mass of which is 1% to 3% of the total mass of boron carbide, titanium boride and silicon carbide;
[0019] (4) The volume average particle size Dv50 of boron carbide is 3μm~5μm, the volume average particle size Dv50 of titanium boride is 1μm~3μm, and the volume average particle size Dv50 of silicon carbide is 1μm~3μm.
[0020] In some implementations, preformed granules are formed using spray granulation.
[0021] The feed temperature for spray granulation is 180℃~220℃, the discharge temperature is 100℃~140℃, the atomization frequency is 9000Hz~11000Hz, and the atmosphere is a protective atmosphere.
[0022] In some embodiments, the temperature of the debinding treatment is 500℃~700℃, the time is 10h~15h, and the atmosphere is a hydrogen-containing atmosphere, in which the volume percentage of hydrogen is 10%~30%.
[0023] Secondly, this application provides a boron carbide composite ceramic material, which is prepared using the preparation method of the boron carbide composite ceramic material in the first aspect.
[0024] Thirdly, this application provides an etching component, the raw material for which the etching component is prepared includes the boron carbide composite ceramic material of the second aspect.
[0025] In some embodiments, the etching component includes a focusing ring made of boron carbide composite ceramic material.
[0026] Compared with traditional technologies, this application has at least the following beneficial effects:
[0027] This application first pre-sintersects particles containing boron carbide, titanium boride, and silicon carbide. Controlling the pre-sintering temperature allows for slight growth of ceramic grains within the particles, enabling partial bonding between the grains while maintaining sintering activity. This not only improves the structural stability of the spherical particles but also provides good fluidity during hot-pressing, allowing the particles to fill grain boundary defect regions and promoting three-dimensional interconnected growth of the sintering neck during hot-pressing, thus increasing material density. Furthermore, because the sintering activity of the ceramic particles remains unchanged and their fluidity is good, they can effectively fill stacking defects during hot-pressing, thereby preventing the formation of material pores and improving material density, synergistically enhancing the etching resistance of the ceramic material. Further, pre-sintering can also further remove binders from the particles, effectively reducing the residual carbon content in the ceramic material, thus preventing carbon residues at the material interfaces from weakening the bonding strength at the ceramic interfaces, thereby improving etching resistance. Therefore, this application pre-sintering and hot-pressing of particles containing boron carbide, silicon carbide and titanium boride can improve the interface effect (such as improving interfacial mass transfer and grain boundary migration), ensure the formation of a ceramic material with good density, good uniformity and low residual carbon content during hot-pressing sintering, reduce the porosity and impurity defects of boron carbide composite ceramic materials, and effectively improve the etching resistance of composite ceramic materials.
[0028] This application also utilizes the synergistic effect of silicon carbide and titanium boride in particulate matter to significantly improve the sinterability of ceramic materials, inhibit grain growth, reduce porosity at grain boundaries, and enhance density. Specifically, silicon carbide and titanium boride maintain their original states within the boron carbide sintered body, each stably distributed as an independent second phase. During sintering, silicon carbide and titanium boride fill the grain boundary defects of boron carbide, resulting in a dense and uniform microstructure in the composite ceramic material. Furthermore, the good chemical compatibility at the grain boundaries allows for the formation of a three-phase interlocked microstructure of boron carbide, silicon carbide, and titanium boride, physically extending and hindering the diffusion path of the etchant, consuming etching energy, and synergistically improving the etching resistance of the boron carbide ceramic material. Attached Figure Description
[0029] Figure 1 This is a SEM image of the cross-section of the boron carbide composite ceramic material prepared in Example 1 of this application;
[0030] Figure 2 A schematic diagram of the focusing ring provided in one embodiment of this application;
[0031] Figure 3 The XRD pattern of the boron carbide composite ceramic material prepared in Example 1 of this application;
[0032] Figure 4 This is a SEM image of the cross-section of the boron carbide composite ceramic material prepared in Comparative Example 3 of this application. Detailed Implementation
[0033] The present application will be further described in detail below with reference to the embodiments and examples. These embodiments and examples are only for illustrating the present application and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the disclosure of the present application more thorough and comprehensive. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. In addition, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.
[0034] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.
[0035] In this application, the terms "first aspect," "second aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first aspect," "second aspect," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.
[0036] In traditional techniques, research has found that the difficulty in sintering boron carbide makes it prone to creating pores at grain boundaries. The high potential energy at grain boundaries and pores makes them susceptible to erosion by high-energy ions and active gases, thus reducing the material's etching resistance.
[0037] The first aspect of this application provides a method for preparing a boron carbide composite ceramic material, the method comprising:
[0038] The particles contain boron carbide, titanium boride, and silicon carbide. The particles have a spherical structure and contain boron carbide at a mass ratio of 70% to 90%, titanium boride at a mass ratio of 5% to 25%, and silicon carbide at a mass ratio of 5% to 25%.
[0039] Boron carbide composite ceramic materials were prepared by pre-sintering and hot-pressing the particulate matter sequentially; the pre-sintering temperature was 1200℃~1500℃.
[0040] This application can effectively improve the density and uniformity of composite ceramic materials, enhance the interfacial effect during sintering, and synergistically improve the etching resistance of boron carbide ceramic materials. For example... Figure 1 As shown, the boron carbide ceramic material prepared in this application exhibits good density. It is understood that the particulate matter containing boron carbide, titanium boride, and silicon carbide in this application refers to the simultaneous presence of boron carbide, titanium carbide, and silicon carbide in a single particle. It can be formed by the composite of multiple boron carbide particles, multiple titanium boride particles, and multiple silicon carbide particles, resulting in a single particulate matter simultaneously containing boron carbide, titanium boride, and silicon carbide.
[0041] In some embodiments, the pre-sintering temperature may be, for example, 1200°C, 1250°C, 1300°C, 1350°C, 1400°C, 1450°C, or 1500°C. The pre-sintering temperature selected above not only allows for further debinding and removal of binders from the particles but also maintains a stable spherical structure, resulting in good structural stability. If the pre-sintering temperature is relatively low, the ceramic crystals may not grow, leading to poor particle bonding strength. The particles are prone to dispersing before hot pressing and sintering, resulting in uneven powder stacking and the formation of pores during sintering. This affects the uniformity and density of the composite ceramic material, thereby reducing its etching resistance. If the pre-sintering temperature is relatively high, the ceramic grains in the particles will grow completely, reducing the sintering activity of the particles. This makes it difficult to grow and form a dense ceramic material during the subsequent hot pressing sintering process. At the same time, at a high pre-sintering temperature, the particles may crack due to excessively rapid debinding, causing some particles to lose their spherical structure. This results in poor fluidity during the hot pressing sintering process, making it impossible to form a uniform and dense composite ceramic material.
[0042] In some embodiments, the boron carbide content in the particulate matter is 70% to 90% by mass, for example, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, or 90%. The boron carbide content selected above in this application allows the composite ceramic material to possess both high hardness and etching resistance, as well as high thermal conductivity. If the boron carbide content is relatively low, due to the low self-migration rate of silicon carbide, it may not be able to sinter to form a dense ceramic structure, resulting in poor sintering density and thus affecting the etching resistance of the composite ceramic material. If the boron carbide content is relatively high, the boron carbide particle size in the resulting composite ceramic material is relatively large, affecting the uniformity and density of the material, thus worsening the etching resistance. Simultaneously, because boron carbide has low thermal conductivity, it also affects the thermal conductivity of the composite ceramic material. During etching, etching-resistant components such as the focusing ring are prone to excessive surface heat, which can damage the etched wafer.
[0043] In some embodiments, the mass percentage of titanium boride in the particulate matter is 5% to 25%, for example, 5%, 7%, 9%, 11%, 13%, 15%, 17%, 19%, 21%, 23%, or 25%. The titanium boride content selected above in this application can effectively suppress the growth of individual grains in the composite ceramic material, thereby improving the flexural strength of the composite ceramic material and meeting the mechanical properties of the focusing ring. If the titanium boride content is relatively low, it will not only result in a poorer suppression effect on grain growth, leading to larger grain sizes in the composite ceramic material and affecting the density and uniformity of the material, but it will also worsen the bonding strength of the composite ceramic material. If the titanium boride content is relatively high, it may be difficult to sinter a dense and uniform composite ceramic material.
[0044] In some embodiments, the mass percentage of silicon carbide in the particulate matter is 5% to 25%, for example, 5%, 7%, 9%, 11%, 13%, 15%, 17%, 19%, 21%, 23%, or 25%. The silicon carbide content selected above in this application acts as a "skeleton" reinforcement during sintering, and in synergy with titanium boride and boron carbide, it can further improve the density of the material during sintering, reduce defects such as porosity, and form a dense microstructure. If the silicon carbide content is relatively low, the "sintering aid" effect with other components is poor, and more pores may remain in the ceramic material, making it difficult to form a high-density ceramic material. If the silicon carbide content is relatively high, it may not act as a skeleton reinforcement but instead serve as a matrix material, resulting in a significant decrease in the macroscopic Vickers hardness of the ceramic material.
[0045] Optionally, the mass ratio of silicon carbide to titanium boride in the particulate matter is greater than or equal to 1:1. Alternatively, the mass ratio of silicon carbide to titanium boride in the particulate matter is (1~5):1, for example, 1:1, 1:2, 1:3, 1:4 or 1:5. In this application, the amount of silicon carbide added to the raw materials is slightly higher than the amount of titanium boride added. As a softer and tougher phase than boron carbide, when the content of titanium carbide is relatively high, it will dilute the high-hardness boron carbide phase in the matrix, resulting in a significant decrease in the macroscopic Vickers hardness of the composite ceramic material. At the same time, during the friction process on the material surface, the softer titanium carbide phase will preferentially undergo plastic deformation and adhesive wear, thereby forming furrows and material transfer, making processing difficult.
[0046] Optionally, the pre-sintering holding time is 3h to 5h, for example, 3.0h, 3.2h, 3.4h, 3.6h, 3.8h, 4.0h, 4.2h, 4.4h, 4.6h, 4.8h, or 5.0h. The pre-sintering heating rate is 1℃ / min to 3℃ / min, for example, 1.0℃ / min, 1.2℃ / min, 1.4℃ / min, 1.6℃ / min, 1.8℃ / min, 2.0℃ / min, 2.2℃ / min, 2.4℃ / min, 2.6℃ / min, 2.8℃ / min, or 3.0℃ / min.
[0047] Optionally, the pre-sintering atmosphere is a protective atmosphere or a hydrogen-containing atmosphere. The protective atmosphere refers to a gas that does not react with the raw materials, such as an argon atmosphere. Optionally, the volume percentage of hydrogen in the hydrogen-containing atmosphere is 10% to 30%, for example, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, or 30%. This application introduces hydrogen during the pre-sintering process, thereby effectively removing surface oxides (such as boron oxide) from the material and further reducing the influence of oxygen on the density of boron carbide ceramic materials.
[0048] The above-mentioned pre-sintering process parameters are selected to further improve the fluidity and structural stability of the particles during the sintering process, thereby ensuring the formation of a composite ceramic material with good density and uniformity during hot pressing sintering, and effectively improving the etching resistance of the composite ceramic material.
[0049] In some embodiments, the hot-pressing sintering temperature is 1800℃~2000℃, for example, 1800℃, 1850℃, 1900℃, 1950℃, or 2000℃. The hot-pressing sintering temperature selected above in this application ensures the compactness of the sintered material while avoiding excessive grain growth. If the sintering temperature is relatively low, the material may have poor compactness and reduced etching resistance. If the hot-pressing sintering temperature is relatively high, excessive grain growth may occur, increasing the total amount of grain boundary sliding. Furthermore, an inhomogeneous microstructure can lead to localized stress concentration in the material, making it prone to crack initiation under high temperature and long-term loads, reducing the high-temperature creep strength and creep life of the composite ceramic material, and making it difficult to meet the high-temperature requirements of plasma etching processes.
[0050] Optionally, the pressure for hot pressing sintering is 30MPa to 50MPa, for example, it can be 30MPa, 32MPa, 34MPa, 36MPa, 38MPa, 40MPa, 42MPa, 44MPa, 46MPa, 48MPa or 50MPa.
[0051] Optionally, the holding time for hot pressing sintering is 0.5h to 2h, for example, it can be 0.5h, 0.8h, 1.0h, 1.1h, 1.4h, 1.5h, 1.7h or 2.0h.
[0052] The heating rate for hot pressing sintering is 3℃ / min to 5℃ / min, for example, it can be 3.0℃ / min, 3.5℃ / min, 4.0℃ / min, 4.5℃ / min or 5.0℃ / min. The vacuum level is below 0.01Pa.
[0053] The above-mentioned hot pressing sintering process parameters are selected to improve the material density and avoid excessive grain growth, thereby effectively improving the material's etching resistance.
[0054] In some embodiments, the sphericity of the particles is 0.85 to 1, for example, 0.85, 0.90, 0.95, or 1.00. It is understood that sphericity is the ratio of the actual surface area of the particles to the surface area of an ideal sphere of the same volume, and its value ranges from 0 to 1; the closer to 1, the more spherical the particles. The particles with the above-mentioned sphericity of this application exhibit good fluidity during sintering, improving the density and uniformity of the sintering process.
[0055] The volume average particle size Dv50 of the particulate matter is 50 μm to 200 μm, for example, it can be 50 μm, 60 μm, 80 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm or 200 μm. It can be selected as 100 μm to 200 μm.
[0056] In some embodiments, the method for forming particulate matter includes: preparing a slurry containing boron carbide, titanium boride, silicon carbide and a binder, granulating it to form preformed particles; and then subjecting the preformed particles to a debinding treatment to prepare particulate matter.
[0057] Optionally, the solid content of the slurry is 40% to 60%, for example, it can be 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, or 60%. 50% to 60% is an option.
[0058] Optionally, the viscosity of the slurry is 300 cps to 500 cps, for example, 300 cps, 350 cps, 400 cps, 450 cps, or 500 cps. The viscosity of the slurry refers to its viscosity at room temperature (25°C). By controlling the viscosity of the slurry as described above, this application can avoid the formation of hollow particles, thereby enabling the formation of dense and regularly shaped spherical particles during the granulation process, synergistically improving the flowability of the particles.
[0059] In some embodiments, a slurry is formed by ball milling. Optionally, the ball-to-material ratio is (4~6):1, for example, 4:1, 5:1, or 6:1; the rotation speed is 250 rpm~300 rpm, for example, 250 rpm, 260 rpm, 270 rpm, 280 rpm, 290 rpm, or 300 rpm; and the time is 10 h~15 h, for example, 10 h, 11 h, 12 h, 13 h, 14 h, or 15 h. Boron carbide balls can be used as the milling media. The ball milling method described above effectively ensures the uniform dispersion of materials in the slurry.
[0060] In some embodiments, the slurry contains 1% to 3% of the total mass of boron carbide, titanium boride, and silicon carbide, for example, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, 2.0%, 2.2%, 2.4%, 2.6%, 2.8%, or 3.0% of the binder. The binder content in the slurry selected above ensures that the slurry has a suitable viscosity and guarantees the formation of preformed particles with a dense structure and good sphericity.
[0061] The binder includes at least one of polyvinyl alcohol (PVA), polyethylene glycol (PEG), and PVAC (polyvinyl acetate).
[0062] In some embodiments, the slurry further contains a dispersant, the mass of which is 1% to 3% of the total mass of boron carbide, titanium boride, and silicon carbide, for example, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, 2.0%, 2.2%, 2.4%, 2.6%, 2.8%, or 3.0%. This application improves the flowability and stability of the slurry by adding a dispersant, effectively reducing material agglomeration.
[0063] The dispersant includes at least one of BYK180, BYK181 and KAOCER 2020.
[0064] Understandably, other additives can be added to the slurry to ensure its performance. For example, defoamers can be added to the slurry to reduce bubbles generated during ball milling. Optionally, defoamers include BYK022.
[0065] In some embodiments, the volume average particle size Dv50 of boron carbide is 3 μm to 5 μm, for example, it can be 3.0 μm, 3.2 μm, 3.4 μm, 3.6 μm, 3.8 μm, 4.0 μm, 4.2 μm, 4.4 μm, 4.6 μm, 4.8 μm, or 5.0 μm; the volume average particle size Dv50 of titanium boride is 1 μm to 3 μm, for example, it can be 1.0 μm, 1.2 μm, 1.4 μm, or 5.0 μm. The particle sizes are 1 μm, 1.6 μm, 1.8 μm, 2.0 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, or 3.0 μm; the volume average particle size (Dv50) of silicon carbide is 1 μm to 3 μm, for example, it can be 1.0 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2.0 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, or 3.0 μm.
[0066] The particle sizes of boron carbide, titanium boride, and silicon carbide selected in this application not only improve the dispersion uniformity of the material, but also, through particle size matching, further promote the three-dimensional interconnected growth of the sintering neck during sintering, increase the sintering density of the material, and effectively improve the etching resistance of the material. If the particle size is relatively large, there may be problems such as poor sintering density and low powder sintering activity.
[0067] In some embodiments, preformed granules are formed by spray granulation. For example, spray granulation is performed using an ultrasonic atomizing granulation device.
[0068] Optionally, the feed temperature for spray granulation is 180℃~220℃, for example, 180℃, 185℃, 190℃, 195℃, 200℃, 205℃, 210℃, 215℃, or 220℃; the discharge temperature is 100℃~140℃, for example, 110℃, 115℃, 120℃, 125℃, 130℃, 135℃, or 140℃; the atomization frequency is 9000Hz~11000Hz, for example, 9000Hz, 9500Hz, 10000Hz, 10500Hz, or 11000Hz; and the atmosphere is a protective atmosphere. The protective atmosphere refers to a gas that does not react with the raw materials, such as an argon atmosphere.
[0069] This application uses spray granulation as described above to form pre-formed particles, ensuring that the formed pre-formed particles have high sphericity and dense structure.
[0070] In some embodiments, the temperature for the adhesive removal process is 500℃~700℃, for example, 500℃, 520℃, 540℃, 560℃, 580℃, 600℃, 620℃, 640℃, 660℃, 680℃, or 700℃; the time is 10h~15h, for example, 10h, 11h, 12h, 13h, 14h, or 15h; the heating rate is 0.3℃ / min~1℃ / min, for example, 0.3℃ / min, 0.4℃ / min, 0.5℃ / min, 0.6℃ / min, 0.7℃ / min, 0.8℃ / min, 0.9℃ / min, or 1.0℃ / min. The adhesive removal temperature selected above ensures that the adhesive and other organic matter are volatilized and discharged from the pre-formed particles, and ensures that the formed particles have a dense structure, avoiding problems such as cracking or breakage of the particles.
[0071] Optionally, the debinding treatment atmosphere is a hydrogen-containing atmosphere, in which the volume percentage of hydrogen is 10% to 30%, for example, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, or 30%. This application performs debinding treatment in a hydrogen-containing atmosphere, utilizing hydrogen to efficiently remove the oxide layer on the surface of boron carbide particles, thereby significantly improving the sintering activity of the material, lowering the sintering temperature, and facilitating the formation of composite materials with high density and excellent mechanical properties.
[0072] Exemplarily, a method for preparing the above-mentioned boron carbide composite ceramic material is provided, comprising the following steps:
[0073] The raw materials are prepared by mixing boron carbide with a particle size of 3μm~5μm at a mass ratio of 70%~90%, titanium boride with a particle size of 1μm~3μm at a mass ratio of 5%~25%, and silicon carbide with a particle size of 1μm~3μm at a mass ratio of 5%~25%. Optionally, the raw materials can be stirred and mixed first. A binder, dispersant, defoamer, and solvent are added to the above raw materials and ball milling is performed to obtain a slurry. The amount of binder added is 1%~3% of the raw material mass, the amount of dispersant added is 1%~3% of the raw material mass, the solid content of the slurry is 40%~60%, and the viscosity is 300cps~500cps. The ball-to-material ratio of ball milling is (4~6):1, the rotation speed is 250rpm~300rpm, and the time is 10h~15h.
[0074] The slurry is prepared into pre-formed granules by spray granulation. The feed temperature of spray granulation is 180℃~220℃, the discharge temperature is 100℃~140℃, the atomization frequency is 9000Hz~11000Hz, and the atmosphere is a protective atmosphere.
[0075] Under a hydrogen-containing atmosphere, the preformed particles are first debinded at 500℃~700℃ for 10h~15h; then the temperature is raised to 1200℃~1500℃ for pre-sintering for 3h~5h, with a heating rate of 1℃ / min~3℃ / min, to obtain particles with a volume average particle size Dv50 of 50μm~200μm. The pre-sintering atmosphere can be a protective atmosphere or a hydrogen-containing atmosphere.
[0076] The above-mentioned particles were hot-pressed and sintered at 1800℃~2000℃, vacuum degree below 0.01Pa, and pressure of 30MPa~50MPa for 0.5h~2h, with a heating rate of 3℃ / min~5℃ / min, to prepare boron carbide composite ceramic materials.
[0077] The second aspect of this application provides a boron carbide composite ceramic material, which is prepared using the preparation method of the boron carbide composite ceramic material of the first aspect.
[0078] The third aspect of this application provides an etching component, the raw material for which the etching component is prepared includes the boron carbide composite ceramic material of the second aspect.
[0079] It is understood that the etching components may include at least one of the following: a cavity, an ESC (Electrostatic Chuck), and a focusing ring, all made of the boron carbide composite ceramic material of this application.
[0080] In some embodiments, such as Figure 2 As shown, the etching component includes a focusing ring made of boron carbide composite ceramic material.
[0081] The embodiments of this application will be described in detail below with reference to examples. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. For experimental methods in the following embodiments where specific conditions are not specified, please refer to the guidelines given in this application, or follow experimental manuals or conventional conditions in the art, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the art.
[0082] In the following examples and comparative examples, boron carbide was purchased from Zhongbo Technology Co., Ltd.; titanium carbide was purchased from Aladdin Materials Co., Ltd.; and silicon carbide was purchased from Xi'an Boer New Materials Co., Ltd.
[0083] The milling media were boron carbide balls, and the binder was PVA. The dispersant was HTA8, brand name DISPERBYK-180. The defoamer was BYK022.
[0084] Example 1
[0085] The raw materials were prepared by mixing boron carbide (4μm Dv50) at 70% by mass, titanium boride (2μm Dv50) at 15% by mass, and silicon carbide (2μm Dv50) at 15% by mass at 250 rpm for 12 hours. A binder, dispersant, defoamer, and water were then added to the raw materials, followed by ball milling to obtain a slurry. The binder, dispersant, and defoamer were each added at 1% of the raw material mass, and the defoamer was added at 0.5% of the raw material mass. The resulting slurry had a solid content of 60% and a viscosity of 500 cps. The ball-to-material ratio was 5:1, the milling speed was 250 rpm, and the time was 12 hours.
[0086] The slurry was prepared into preformed particles by spray granulation under argon protection. The feed temperature of spray granulation was 200℃, the discharge temperature was 120℃, and the rotation speed was 10000Hz.
[0087] Under a hydrogen-containing atmosphere, the preformed particles were first debinded at 600℃ for 12 hours, with a hydrogen to argon volume flow rate ratio of 2:8 and a heating rate of 0.5℃ / min. Then, the temperature was increased to 1200℃ at a rate of 2℃ / min for pre-sintering for 4 hours to obtain particles with a Dv50 of 100μm. During the pre-sintering process, hydrogen and argon gas with a volume flow rate ratio of 2:8 were still introduced.
[0088] The above-mentioned particles were hot-pressed and sintered at 1900℃, vacuum degree below 0.001Pa, and pressure of 40MPa for 1 hour, with a heating rate of 5℃ / min. The resulting cross-sectional image is shown below. Figure 1 The boron carbide composite ceramic material shown has the following XRD pattern: Figure 3 As shown in the XRD pattern, the boron carbide composite ceramic material is composed of boron carbide, titanium boride, and silicon carbide, with no other phases formed.
[0089] Example 2
[0090] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that the mass percentage of boron carbide in the raw materials was 90%, titanium boride was 5%, and silicon carbide was 5%. The volumetric flow rate ratio of hydrogen and argon was 1:9 during the debinding and pre-sintering processes.
[0091] Example 3
[0092] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that the mass percentage of boron carbide in the raw materials was 70%, titanium boride was 25%, and silicon carbide was 5%; the amount of defoamer added to the slurry was 1% of the mass of the raw materials. Argon gas protection was used only during the pre-sintering process.
[0093] Example 4
[0094] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that the amount of binder added to the slurry was 3% of the raw material mass, the amount of dispersant added was 3% of the raw material mass, the amount of defoamer added was 1.5% of the raw material mass, and the resulting slurry viscosity was 300 cps.
[0095] Example 5
[0096] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that only argon gas was used for protection during the debinding and pre-sintering processes, and the pre-sintering temperature was 1500°C.
[0097] Comparative Example 1
[0098] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that titanium boride was replaced with an equal mass of silicon carbide.
[0099] Comparative Example 2
[0100] Boron carbide composite ceramic materials were prepared according to the method of Example 1, except that silicon carbide was replaced with an equal mass of titanium boride.
[0101] Comparative Example 3
[0102] Boron carbide composite ceramic materials were prepared according to the method in Example 1, the difference being that the particles were not pre-sintered, but rather the debinding particles were directly hot-pressed and sintered. The cross-sectional SEM image of the resulting boron carbide composite ceramic material is shown below. Figure 4 As shown.
[0103] Comparative Example 4
[0104] Boron carbide ceramic materials were prepared by hot pressing and sintering at 2050℃ using only boron carbide as raw material.
[0105] Comparative Example 5
[0106] Silicon carbide prepared by commercially available chemical vapor deposition.
[0107] Comparative Example 6
[0108] Boron carbide composite ceramic materials were prepared according to the method of Example 2, except that the volume flow ratio of hydrogen and argon during the debinding process was 2:8, only argon was used for protection during the pre-sintering process, and the pre-sintering temperature was 1800℃.
[0109] The etching rates of the materials prepared in the above embodiments and comparative examples were tested, and the test methods included:
[0110] The sample was etched using an ICP inductively coupled plasma etching system. The etching gases were CF4 (20 sccm) and Ar (10 sccm). The coil power was 800 W, the bias power was 200 W, the chamber pressure was 10 Pa, and the etching time was 30 min. After etching, the etching rate was calculated based on the mass difference before and after the analysis balance. The test results are shown in Table 1.
[0111] Table 1
[0112]
[0113] As can be seen from the table above:
[0114] (1) Compared with Example 4, Example 1 shows that by controlling the viscosity of the slurry, this application ensures the formation of dense particles during the granulation process, avoids the formation of hollow particles and particle cracking, and reduces the introduction of carbon elements in the material, thereby improving the density and uniformity of the material during sintering, and effectively improving the etching resistance and stability.
[0115] (2) Compared with Example 5, it can be seen that by introducing hydrogen gas during the debinding process or pre-sintering process, this application can remove oxides (such as boron oxide) contained in the material, effectively avoid oxygen residue, and improve the etching resistance of the material.
[0116] (3) Compared with Comparative Examples 1-5, Example 1 shows that the introduction of titanium boride and silicon carbide into boron carbide in this application not only reduces the sintering temperature of boron carbide but also improves the etching resistance of the material. Furthermore, during the sintering process, this application first uses particles containing boron carbide, titanium boride, and silicon carbide for pre-sintering, improving the fluidity of the raw materials. This promotes the three-dimensional interconnected growth of the sintering neck during hot pressing, effectively increasing the material density and ensuring good material uniformity, thereby synergistically improving the etching resistance of the boron carbide ceramic material. Among them, such as... Figure 1 and Figure 4 As shown, the ceramic material prepared in Example 1 has good density and no pores, and has good etching resistance. In contrast, the ceramic material prepared in Comparative Example 3 has obvious pores, and the etching rate of different regions is different during the etching process, which significantly reduces the etching resistance.
[0117] (4) Compared with Comparative Example 6, it can be seen that because the pre-sintering temperature of Example 6 is higher, the particles break before hot pressing sintering, which leads to uneven distribution of particles during hot pressing sintering. The sintered ceramic material has many pores and poor sintering density. During the etching process, the etching rate of each region is different, which significantly reduces the etching resistance.
[0118] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0119] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.
Claims
1. A method for preparing a boron carbide composite ceramic material, characterized in that, The preparation method includes: Particulate matter containing boron carbide, titanium boride, and silicon carbide is formed. The particulate matter has a spherical structure. The particulate matter contains 70% to 90% boron carbide by mass, 5% to 25% titanium boride by mass, and 5% to 25% silicon carbide by mass. The boron carbide composite ceramic material is prepared by sequentially pre-sintering and hot-pressing the particles; the pre-sintering temperature is 1200℃~1500℃.
2. The method for preparing boron carbide composite ceramic material as described in claim 1, characterized in that, The preparation method also satisfies at least one of the following conditions: (1) The sphericity of the particles is 0.85~1, and the volume average particle size Dv50 is 50μm~200μm; (2) The holding time for the pre-sintering is 3h~5h, the heating rate is 1℃ / min~3℃ / min, and the atmosphere is a protective atmosphere or a hydrogen-containing atmosphere. (3) The hot pressing sintering temperature is 1800℃~2000℃, the pressure is 30MPa~50MPa, the holding time is 0.5h~2h, the heating rate is 3℃ / min~5℃ / min, and the vacuum degree is less than 0.01Pa.
3. The method for preparing boron carbide composite ceramic material as described in claim 1 or 2, characterized in that, The method for forming the particulate matter includes: A slurry containing the boron carbide, the titanium boride, the silicon carbide, and a binder is prepared, and then granulated to form preformed particles; The pre-formed granules are degummed to prepare the granules.
4. The method for preparing boron carbide composite ceramic material as described in claim 3, characterized in that, The slurry has a solid content of 40% to 60% and a viscosity of 300 cps to 500 cps.
5. The method for preparing boron carbide composite ceramic material as described in claim 3, characterized in that, The slurry satisfies at least one of the following conditions: (1) The slurry is formed by ball milling; the ball-to-material ratio of the ball milling is (4~6):1, the rotation speed is 250rpm~300rpm, and the time is 10h~15h; (2) The slurry contains 1% to 3% of the total mass of the binder, the titanium boride, and the silicon carbide; (3) The slurry also contains a dispersant, the mass of which is 1% to 3% of the total mass of the boron carbide, the titanium boride and the silicon carbide; (4) The volume average particle size Dv50 of the boron carbide is 3μm~5μm, the volume average particle size Dv50 of the titanium boride is 1μm~3μm, and the volume average particle size Dv50 of the silicon carbide is 1μm~3μm.
6. The method for preparing boron carbide composite ceramic material as described in claim 3, characterized in that, The preformed granules are formed by spray granulation. The feed temperature of the spray granulation is 180℃~220℃, the discharge temperature is 100℃~140℃, the atomization frequency is 9000Hz~11000Hz, and the atmosphere is a protective atmosphere.
7. The method for preparing boron carbide composite ceramic material as described in claim 3, characterized in that, The debinding treatment is performed at a temperature of 500℃~700℃ for 10h~15h in a hydrogen-containing atmosphere, where the volume percentage of hydrogen is 10%~30%.
8. A boron carbide composite ceramic material, characterized in that, The boron carbide composite ceramic material is prepared using the preparation method of boron carbide composite ceramic material according to any one of claims 1-7.
9. An etching component, characterized in that, The raw materials for preparing the etched component include the boron carbide composite ceramic material as described in claim 8.
10. The etching component as claimed in claim 9, characterized in that, The etching component includes a focusing ring made of the boron carbide composite ceramic material.