High heat-resistant device and method for manufacturing the same
By oxidizing a tantalum substrate to form a tantalum carbide layer through a carbonization process, the method enhances the heat resistance and stability of silicon carbide crystal growth equipment, addressing corrosion and peeling issues in conventional coatings.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- IND TECH RES INST
- Filing Date
- 2024-11-27
- Publication Date
- 2026-05-22
AI Technical Summary
The manufacturing process of silicon carbide single crystals is hindered by corrosion, cracking, and delamination of carbon substrates due to high temperatures and carrier gases, and conventional tantalum carbide coatings suffer from poor crystalline properties and thermal shock-induced peeling.
A method involving oxidation of a tantalum substrate to form a tantalum oxide layer, followed by a carbonization reaction to convert it into a tantalum carbide layer, which is then used as a protective coating for high-temperature applications.
The method produces a high-heat-resistant tantalum carbide layer with improved uniformity, density, and peel resistance, suitable for high-temperature processes, and addresses the issues of peeling and poor crystalline properties of conventional coatings.
Smart Images
Figure 2026085208000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a high-temperature resistant apparatus, and more particularly to a high-temperature resistant apparatus suitable for the synthesis of growing high-purity semi-insulating silicon carbide powder, and a method for manufacturing the same. [Background technology]
[0002] Silicon carbide (SiC) possesses excellent physicochemical properties and is suitable for applications in semiconductor processes, wireless communications, and power module-related industries. However, the manufacturing process of SiC single crystals requires high temperatures of over 1800°C and necessitates the use of carrier gases such as hydrogen (H2), argon (Ar), ammonia (NH3), and hydrocarbon compounds. Because Si2N4 is produced by the reaction with ammonia, SiC on a carbon substrate is prone to corrosion, cracking, or delamination after vaporization at high temperatures above 1500°C.
[0003] To reduce crystal growth or epitaxial defects, a protective layer is typically formed by coating a graphite crucible with tantalum carbide (TaC), and a high-density crystalline TaC coating is obtained using chemical vapor deposition (CVD). However, the crystalline properties of TaC produced by CVD are poor because it grows only in specific directions. As a result, when the TaC-coated graphite crucible is subjected to thermal shock, cracks and delamination occur, and NH3, H2, and other substances in the carrier gas can rapidly corrode the carbon substrate. [Overview of the project] [Problems that the invention aims to solve]
[0004] The present invention provides a high-temperature resistant device and a method for manufacturing the same, which can produce tantalum carbide, which has high heat resistance under normal pressure and is resistant to peeling, as a surface protective layer for the high-temperature resistant device. [Means for solving the problem]
[0005] The present invention provides a method for manufacturing a high heat-resistant device, comprising: providing a tantalum substrate as the device body; oxidizing the tantalum substrate in an oxygen-containing environment to form a tantalum oxide layer on the surface of the tantalum substrate, wherein the temperature of the oxidation treatment is between 100°C and 1100°C; and subsequently burying the oxidized tantalum substrate in a carbon-containing material and carrying out a carbonization reaction in an inert gas to convert the tantalum oxide layer into a carbide tantalum layer.
[0006] In one embodiment of the present invention, the oxygen-containing environment described above includes oxygen, water vapor, an inert gas, or a combination thereof.
[0007] In one embodiment of the present invention, the pressure of the oxidation treatment described above is atmospheric pressure.
[0008] In one embodiment of the present invention, the time for the oxidation treatment described above is between 15 and 120 minutes.
[0009] In one embodiment of the present invention, the tantalum oxide layer described above has the chemical formula Ta x O y It is expressed as follows, and y / x is between 0.5 and 2.5.
[0010] In one embodiment of the present invention, the inert gas described above includes argon gas, helium gas, or a combination thereof.
[0011] In one embodiment of the present invention, the pressure of the carbonization reaction described above is atmospheric pressure, the reaction temperature is between 1500°C and 2100°C, and the reaction time is between 15 minutes and 2 hours.
[0012] In one embodiment of the present invention, the carbon-containing substance described above includes carbon powder, graphite powder, activated carbon, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), sucrose, glucose, or a combination thereof.
[0013] In one embodiment of the present invention, the carbonization reaction described above may be further followed by carbon removal.
[0014] The high heat-resistant device of the present invention includes a tantalum substrate and a tantalum carbide layer. The tantalum carbide layer is a layer formed on the surface of the tantalum substrate, and the thickness of the tantalum carbide layer is between 2 μm and 100 μm.
[0015] In another embodiment of the present invention, the specific surface area of the tantalum carbide layer described above is 0.1 cm². 2 / g~2cm 2 It is between / g.
[0016] In another embodiment of the present invention, the high-temperature resistant apparatus described above includes a crucible, aerospace equipment, high-temperature reaction vessel equipment, or crystal growth equipment. [Effects of the Invention]
[0017] As described above, the present invention provides a method for producing high heat-resistant equipment by generating TaC from an in-situ reaction of carbon by subjecting a tantalum substrate to a high-temperature thermal reaction in an atmospheric furnace. This method has advantages such as a simple process, being environmentally friendly and non-toxic, allowing for adjustment of film thickness, high uniformity, high density of the film layer, and high reusability. Furthermore, it can solve the problem of coating peeling caused by using conventional TaC coating methods.
[0018] To make the above-mentioned features and advantages of the present invention easier to understand, examples are given below and described in detail with accompanying drawings. [Brief explanation of the drawing]
[0019] [Figure 1] This is a flowchart illustrating the manufacturing process of a high-temperature resistant device according to one embodiment of the present invention. [Figure 2A] Figure 1 is a simplified diagram of the oxidation treatment in step 110. [Figure 2B] It is a schematic diagram of the carbonization reaction in step 120 of FIG. 1. [Figure 3] It is a scanning electron microscope (SEM) image of the sample of Experimental Example 3 of the present invention. [Figure 4] It is an SEM image of the sample of Experimental Example 27 of the present invention. [Figure 5] It is an SEM image of the sample of Experimental Example 4 of the present invention. [Figure 6] It is an SEM image of the sample of Experimental Example 14 of the present invention. [Figure 7] It is an SEM image of the sample of Comparative Example 1. [Figure 8] It is an SEM image of the sample of Comparative Example 2.
Embodiments for Carrying Out the Invention
[0020] FIG. 1 is a flowchart diagram of a manufacturing process of a high heat-resistant device according to one embodiment of the present invention.
[0021] Referring to FIG. 1, first, in step 100, a tantalum substrate is provided as the device body. Here, the tantalum substrate refers to a substrate whose entire material is tantalum, and it may be a sheet-like substrate, a strip-like substrate, a spherical substrate, or a substrate processed into a specific structure.
[0022] Next, in step 110, the above-described tantalum substrate is oxidized in an oxygen-containing environment to form an oxide layer of tantalum on the surface of the tantalum substrate. Here, the oxide of tantalum has the chemical formula Ta x O yThe expression is given by y / x, where y / x is between 0.5 and 2.5. Under low-oxygen conditions, y / x = 0.5, and under high-oxygen conditions, y / x = 2.5. The oxygen-containing environment described above includes oxygen, water vapor, inert gas, or a combination thereof, for example, a combination of oxygen and an inert gas, or water vapor and an inert gas. In one embodiment, the aforementioned oxygen-containing environment refers to an environment with an oxygen content of 1 vol% to 100 vol%. In one embodiment, the temperature of the oxidation treatment described above is between 100°C and 1100°C, for example, between 120°C and 1100°C, between 500°C and 1100°C, or between 120°C and 500°C. In one embodiment, the pressure of the oxidation treatment described above is atmospheric pressure, for example, 1 atm. In one embodiment, the duration of the oxidation treatment described above is between 15 minutes and 120 minutes, for example, between 30 minutes and 120 minutes. Figure 2A shows a simplified diagram of the oxidation treatment in step 110, and the above oxidation treatment can be performed by placing the tantalum substrate 200 inside the alumina vessel 210.
[0023] Next, in step 120, the tantalum substrate after oxidation treatment is embedded in a carbon-containing material and a carbonization reaction is carried out in an inert gas to convert the tantalum oxide layer described above into a tantalum carbide layer. Here, the carbon-containing material described above is, for example, carbon powder, graphite powder, activated carbon, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), sucrose, glucose, or a combination thereof, but the present invention is not limited to these. In one embodiment, the inert gas described above includes argon gas, helium gas, or a combination thereof. In one embodiment, the pressure of the carbonization reaction described above is atmospheric pressure, for example, 1 atm. In one embodiment, the reaction temperature described above is between 1500°C and 2100°C. In one embodiment, the reaction time described above is between 15 minutes and 2 hours. Figure 2B shows a simplified diagram of the carbonization reaction in step 120. The carbonization reaction can be carried out by placing the oxidized tantalum substrate 200a inside a graphite torch 220 containing the carbon-containing substance 230.
[0024] After step 120, further, step 130 can be executed to perform carbon removal. For example, the remaining carbon-containing substances can be removed by high-temperature treatment. Here, the temperature of the high-temperature treatment is about 800°C to 900°C, and in an atmospheric environment, the holding time is about 1 hour to 2 hours, but the present invention is not limited thereto.
[0025] Another embodiment of the present invention is a high heat-resistant device formed using the above manufacturing process. Therefore, the high heat-resistant device includes a tantalum substrate and a tantalum carbide layer, and the tantalum carbide layer is a layer formed on the surface of the tantalum substrate. Such a high heat-resistant device can also be used at temperatures exceeding 1000°C. For example, it can be used as a device for a crucible, an aerospace accessory, an accessory for a high-temperature reaction vessel, or an accessory for crystal growth. In this embodiment, the thickness of the tantalum carbide layer is, for example, between 2 μm and 100 μm. When the thickness of the tantalum carbide layer is 2 μm or more, the requirement of uniformity can be satisfied. When the thickness of the tantalum carbide layer is 100 μm or less, the probability of film layer separation can be reduced. In this embodiment, the specific surface area of the tantalum carbide layer is 0.1 cm 2 / g to 2 cm 2 / g. When the specific surface area of the tantalum carbide layer is 0.1 cm 2 / g or less, the gas adsorption effect may deteriorate. When the specific surface area of the tantalum carbide layer is 2 cm 2 / g or more, the film layer structure may become unstable and the mechanical strength may decrease.
[0026] The following lists experiments for verifying the implementation effects of the present invention, but the present invention is not limited to these contents.
[0027] 〈Raw materials〉
[0028] 〈Experimental Examples 1 to 29〉
[0029] First, a sheet-like tantalum substrate was prepared. Next, the tantalum substrate was placed in an alumina vessel and subjected to the oxidation treatment shown in Table 1 under atmospheric pressure. Here, the oxidation treatment was carried out in an atmospheric furnace. Next, the tantalum substrate after oxidation (with a tantalum oxide layer formed on the surface) was embedded in a graphite vessel filled with carbon powder (purchased from SEC Carbon, average particle size 20 μm), and the carbon powder was used as the carbon-containing material. The carbonization reaction shown in Table 1 was carried out under atmospheric pressure. Here, the inert gas for the carbonization reaction was argon gas or helium gas. Finally, carbon removal was performed under conditions of 800°C, and ultimately, samples for Experimental Examples 1 to 29 were obtained.
[0030] <Comparative Examples 1-2>
[0031] Carbonization was performed using the same process as in the experimental example above, except for the oxidation treatment. Please refer to Table 1 for the carbonization conditions.
[0032] Scanning electron microscope (SEM) analysis: The thickness of the tantalum oxide layer formed after oxidation treatment in Experimental Examples 1-29 was observed using an SEM scale bar, and the measurement results are shown in Table 1 below. The cross-sections of the samples in Experimental Examples 1-29 and Comparative Examples 1-2 were observed using an SEM, and the thickness of the tantalum carbide layer was obtained based on the SEM scale bar, and the measurement results are shown in Table 1 below.
[0033] [Table 1-1] [Table 1-2] In Table 1, under "Whether or not water vapor was introduced," O indicates that water vapor was introduced, and X indicates that water vapor was not introduced. In Table 1, an "O" in "Peel Resistance" indicates excellent peel resistance, while an "X" indicates poor peel resistance.
[0034] Uniformity Analysis: Based on SEM images, the difference between the maximum and minimum thicknesses of the microstructure of the same film layer was used as evaluation data for uniformity. The measurement results showed that experimental examples 1-4 and 26-27 had the best uniformity (thickness difference within 3 μm), and experimental examples 9, 14-17 and 28-29 also showed good uniformity (thickness difference of 5 μm to 10 μm). On the other hand, in comparative example 1, a tantalum carbide layer was basically not formed, and the thickness difference in comparative example 2 was 10 μm.
[0035] Density: The density of the tantalum carbide layer is determined using a relative method based on the specific surface area. A lower specific surface area value indicates better density.
[0036] As can be seen from the measurement data, the specific surface area of the tantalum carbide layers in experimental examples 6-17 is approximately 0.13 cm². 2 / g~1.60cm 2 With a density of / g, excellent density, and superior peel resistance, it is a favorable choice in terms of heat conduction efficiency and usability in high-temperature processes at the backend. The specific surface area of the tantalum carbide layers in Experimental Examples 1-5 is approximately 3.74 cm². 2 / g~6.94cm 2 The value is / g, and the specific surface area of the tantalum carbide layer in Comparative Example 2 is approximately 3.45 cm². 2 Because of its low density ( / g), it is not suitable for backend applications. In particular, Comparative Example 2 has poor density and an excessively long production time, resulting in relatively poor thermal conductivity.
[0037] High-temperature resistance analysis: The melting point of tantalum carbide is 3880°C, while the typical crystal growth process temperature is between 2000°C and 2300°C. Because the material itself is hotter than the process temperature, it can withstand high-temperature processes regardless of thickness, uniformity, or density, without problems such as delamination, cracking, or damage.
[0038] Analysis of peel resistance: Test specimens were fixed, and the surface layer of tantalum carbide was peeled off using a highly adhesive polymer thin film. The degree of peeling when force was applied instantaneously was observed. The detailed results are as follows: Experimental examples 1-17, 19-20, and 23 showed good peel resistance, while the other experimental examples showed relatively poor peel resistance. Among these, the tantalum carbide layer treated at 600°C was very unstable and brittle, and completely peeled off at 1100°C. Comparative examples 1-2 showed poor peel resistance because no oxidation treatment was performed.
[0039] Figures 3 and 4 are SEM images of the samples from Experimental Example 3 and Experimental Example 27, respectively. As can be seen from Table 1, Figures 3 and 4 above, the thickness of the tantalum oxide layer can be increased from 8 μm to 50 μm by raising the oxidation temperature from 120°C to 1100°C. Figures 5 and 6 are SEM images of the samples from Experimental Example 4 and Experimental Example 14. As can be seen from Table 1, Figures 5 and 6 above, the only difference between Experimental Example 4 and Experimental Example 14 is the oxidation treatment time, so the length of the oxidation treatment time also affects the thickness of the tantalum carbide layer.
[0040] Furthermore, comparing Experimental Example 4 and Experimental Example 9, it was found that the thickness of the tantalum oxide layer could be increased from 8 μm to 68 μm when water vapor was introduced. Therefore, it can be verified that the thickness of the tantalum oxide layer is affected by oxidation temperature, oxidation time, and water vapor, and that the thickness of the tantalum oxide layer increases with increasing oxidation temperature, increasing oxidation time, or introducing water vapor.
[0041] Comparing Experimental Example 15 and Experimental Example 16, increasing the carbonization temperature from 1500°C to 2100°C increases the thickness of the tantalum carbide layer from 75 μm to 80 μm. Comparing Experimental Example 28 and Experimental Example 29, increasing the carbonization time from 60 minutes to 120 minutes increases the thickness of the tantalum carbide layer from 94 μm to 100 μm. Therefore, when the thickness of the tantalum carbide layer is the same as the thickness of the tantalum oxide layer, it is mainly affected by the carbonization temperature, but the degree of change is not large. On the other hand, comparing Experimental Example 3 and Experimental Example 17, at the same carbonization temperature of 2100°C and carbonization time of 60 minutes, the thickness of the tantalum carbide layer increased from 8 μm to 88 μm, while the original thickness of the tantalum oxide layer was 4 μm and 75 μm, respectively. Therefore, it can be verified that the thickness of the tantalum carbide formation is more susceptible to the thickness of the tantalum oxide layer.
[0042] Figures 7 and 8 are SEM images of the samples from Comparative Example 1 and Comparative Example 2, respectively. As can be seen from Table 1, Figures 7 and 8 above, in Comparative Example 1, almost no tantalum carbide was formed, and in Comparative Example 2, the density of the tantalum carbide layer was poor.
[0043] As described above, the present invention first generates tantalum oxide on the surface of a tantalum substrate by oxidation treatment, and then performs a carbonization reaction to convert the aforementioned tantalum oxide into tantalum carbide. Therefore, compared to methods that directly carbonize tantalum at higher temperatures and for longer periods, it is possible to generate TaC from an in-situ reaction of carbon at lower temperatures and in a shorter time. Thus, the process is simple, environmentally friendly and non-toxic, the film thickness can be adjusted, it has high uniformity, the film layer is densely packed, and it has a high reusability rate. Furthermore, it can solve the problem of coating peeling caused by conventional methods of forming TaC coatings on the surface of graphite crucibles.
[0044] Although the present invention has been disclosed by the above embodiments, these do not limit the invention. A person with ordinary skill in the art may make some modifications and improvements without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention shall be defined by the claims described below. [Industrial applicability]
[0045] The high heat-resistant apparatus and its manufacturing method of the present invention can be used for the manufacture of crucibles, aerospace equipment, high-temperature reaction vessel equipment, or crystal growth equipment. [Explanation of symbols]
[0046] 100, 110, 120, 130 I 200 Tantalum base material 200a Tantalum substrate after oxidation treatment 210 Aluminum Oxide Crucible 220 Graphite Turtle 230 Carbon-containing substances
Claims
1. To provide a tantalum substrate as the main body of the device, The tantalum substrate is oxidized in an oxygen-containing environment to form a tantalum oxide layer on the surface of the tantalum substrate, and the temperature of the oxidation treatment is between 100°C and 1100°C. The tantalum substrate after the oxidation treatment is embedded in a carbon-containing material, and a carbonization reaction is carried out in an inert gas to convert the tantalum oxide layer into a tantalum carbide layer. A method for manufacturing a high-temperature resistant device, including the device itself.
2. The method for manufacturing a high heat-resistant device according to claim 1, wherein the oxygen-containing environment includes oxygen, water vapor, an inert gas, or a combination thereof.
3. The method for manufacturing a high heat-resistant device according to claim 1, wherein the pressure of the oxidation treatment is atmospheric pressure.
4. The method for manufacturing a high heat-resistant device according to claim 1, wherein the oxidation treatment time is between 15 minutes and 120 minutes.
5. The tantalum carbide layer has the chemical formula Ta ｘ O ｙ A method for manufacturing a high heat-resistant device according to claim 1, wherein the equation is expressed as and y / x is between 0.5 and 2.
5.
6. The method for manufacturing a high heat-resistant apparatus according to claim 1, wherein the inert gas includes argon gas, helium gas, or a combination thereof.
7. A method for manufacturing a high heat-resistant device according to claim 1, wherein the pressure of the carbonization reaction is atmospheric pressure, the reaction temperature is between 1500°C and 2100°C, and the reaction time is between 15 minutes and 2 hours.
8. A method for manufacturing a high heat-resistant apparatus according to claim 1, wherein the carbon-containing substance comprises carbon powder, graphite powder, activated carbon, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), sucrose, glucose, or a combination thereof.
9. A method for manufacturing a high heat-resistant device according to claim 1, further comprising removing carbon after the carbonization reaction.
10. Tantalum base material and The tantalum carbide layer is a layer formed on the surface of the tantalum substrate, A high heat-resistant device comprising the above, wherein the thickness of the tantalum carbide layer is between 2 μm and 100 μm.
11. The specific surface area of the tantalum carbide layer is 0.1 cm². ２ / g to 2cm ２ The high heat-resistant device according to claim 10, wherein the value is between / g.
12. The high heat-resistant device according to claim 10, wherein the high heat-resistant device includes a crucible, an aerospace accessory, a high-temperature reaction vessel accessory, or a crystal growth accessory.