Manufacturing method of quartz glass surface high-temperature-resistant coating with high infrared reflectivity

Abstract

The invention relates to the technical field of quartz glass surface treatment, in particular to a manufacturing method of a quartz glass surface high-temperature-resistant coating with high infrared reflectivity, and the method comprises the following steps: (1) preparing a water-based dispersion liquid: mixing deionized water, ethylene glycol, polyethylene glycol and a water reducing agent; (2) preparing coating slurry: mixing quartz glass micro powder, hydrophilic fumed silica particles, a non-metal sintering aid and a water-based dispersion liquid, and carrying out ball milling treatment; (3) carrying out hydrophilization treatment on the quartz glass substrate; (4) coating of a slurry layer: coating the slurry obtained in the step (2) on the surface of the quartz glass substrate treated in the step (3); and (5) sintering the slurry layer: performing high-temperature heat treatment on the quartz glass treated in the step (4) to form the high-temperature-resistant coating. According to the preparation method, the high-temperature-resistant coating with the infrared relative reflectivity of 90% or above can be prepared, and the heating performance and the temperature uniformity of the quartz glass-based reaction cavity are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of quartz glass surface treatment technology, and more specifically, to a method for manufacturing a high-temperature resistant coating on the surface of quartz glass with high infrared reflectivity. Background Technology

[0002] In the semiconductor manufacturing field, quartz glass, with its high purity, excellent high-temperature resistance, and extremely low coefficient of thermal expansion, has become an indispensable key substrate in chip manufacturing processes. It is widely used in wafer carriers, reaction chamber components, and plays a crucial role in precision processes such as photolithography, etching, ion implantation, and heat treatment. However, quartz glass is transparent, with a relative reflectivity of only 30%-40% in the infrared spectrum. This means that during high-temperature processes, a large amount of heat is lost through radiation penetrating the glass surface. This not only increases energy consumption costs but also causes uneven temperature fields inside the reaction chamber, directly affecting the uniformity of chemical processes on the wafer surface and leading to fluctuations in product performance.

[0003] To address these issues, two mainstream technological approaches have emerged within the industry: The first method is the doping modification technology for quartz glass materials. This technology involves introducing functional dopant components (such as...) during the high-temperature preparation stage of molten quartz (typically a melting process at 1700-1800℃). , , Transition metal ions, or , Oxide nanoparticles (such as those used in quartz glass) can be used to selectively scatter and absorb infrared photons, thereby altering the intrinsic optical constants (refractive index) of quartz glass. Extinction coefficient This method improves reflectivity in specific infrared bands (especially the critical 3-14μm mid-to-long-wave infrared region in semiconductor processes). However, this method is complex and introduces metallic elements, which does not meet the stringent purity requirements of the semiconductor industry for quartz glass.

[0004] The second method involves preparing a pure gold infrared reflective coating on the surface of quartz glass. This technology uses processes such as physical vapor deposition (PVD, such as magnetron sputtering and electron beam evaporation), chemical vapor deposition (CVD), or sol-gel to construct a thin or thick pure gold coating on the quartz glass surface. Utilizing the high infrared reflectivity of pure gold, it achieves efficient reflection of infrared wavelengths. However, although this gold coating has an infrared reflectivity of over 95%, its preparation cost is relatively high, and pure gold has a low melting point (1064℃). At high temperatures, the infrared reflectivity of the gold coating decreases significantly with increasing temperature, making it unsuitable for applications above 1000℃.

[0005] Therefore, there is an urgent need for a quartz glass surface treatment method that is simple in process, low in cost, and capable of producing high-temperature resistant and high infrared reflectivity coatings, in order to overcome the shortcomings of existing technologies. Summary of the Invention

[0006] The main objective of this invention is to propose a method for manufacturing a high-temperature resistant coating on the surface of quartz glass with high infrared reflectivity. This method is simple, has low production cost, and can produce a coating that can withstand temperatures above 1000℃ and has an infrared relative reflectivity of over 90%, effectively improving the heating performance and temperature uniformity of the quartz glass-based reaction chamber.

[0007] To address the aforementioned technical problems, this invention proposes a method for manufacturing a high-temperature resistant coating on the surface of quartz glass with high infrared reflectivity, characterized by comprising the following steps: (1) Preparation of aqueous dispersion: Mix deionized water, ethylene glycol, polyethylene glycol and water-reducing agent evenly; (2) Preparation of coating slurry: Quartz glass micro powder, hydrophilic fumed silica particles, non-metallic sintering aid and aqueous dispersion obtained in step (1) are mixed and then placed in a ball mill jar with grinding balls for ball milling. (3) Hydrophilic treatment of quartz glass substrate surface: The quartz glass is cleaned and dried; then plasma treatment is performed; (4) Coating of slurry layer: The slurry obtained in step (2) is coated on the surface of the quartz glass substrate treated in step (3), and then dried; (5) Sintering of slurry layer: The quartz glass after step (4) is subjected to high temperature heat treatment to make the slurry layer sintered and dense, forming a high temperature resistant coating.

[0008] In the above technical solution, further, in step (1), the proportion of the aqueous dispersion by mass percentage is: 50-70% deionized water, 20-40% ethylene glycol, 8% polyethylene glycol, and 2% water-reducing agent.

[0009] In any of the above technical solutions, further, in step (1), the molecular weight of polyethylene glycol is one or more of 600, 2000, and 6000 g / mol.

[0010] In any of the above technical solutions, further, in step (1), the water-reducing agent is a polycarboxylate ammonium salt dispersant.

[0011] In any of the above technical solutions, further, in step (2), the mass ratio of quartz glass micro powder to hydrophilic fumed silica particles is 10:1-18:1.

[0012] In any of the above technical solutions, further, in step (2), the total silica content in the coating slurry is 50-75% by mass percentage.

[0013] In any of the above technical solutions, further, in step (2), the non-metallic sintering aid is one or more of boric acid, boron oxide, boron carbide, silicon carbide, and silicon nitride.

[0014] In any of the above technical solutions, further, in step (2), the non-metallic sintering aid is 2-10 wt% of the total amount of hydrophilic fumed silica particles.

[0015] In any of the above technical solutions, further, in step (2), the ball milling speed is 200-350 rpm and the ball milling time is 8-16 h.

[0016] In any of the above technical solutions, further, in step (3), the plasma treatment time is 5-10 min.

[0017] In any of the above technical solutions, further, in step (5), the high-temperature heat treatment steps are as follows: the quartz glass is heated from room temperature to 100°C and held at that temperature, then heated to 500°C and held at that temperature, then heated to 800°C, then heated to 1000°C, and finally heated to the sintering temperature and held at that temperature, and then cooled to 150°C in stages and cooled with the furnace.

[0018] In any of the above technical solutions, further, in step (5), the sintering temperature is 1100-1150℃ and the holding time is 1-3h.

[0019] Beneficial effects: Compared with existing technologies, The coating prepared by this invention uses quartz glass micropowder and hydrophilic fumed silica particles as the main raw materials, combined with non-metallic sintering aids, to form a dense inorganic coating structure after high-temperature sintering. This coating can withstand temperatures above 1000℃, and after treatment at 1000℃, its infrared relative reflectivity can still remain above 90%, without cracking or peeling. In contrast, the reflectivity of traditional pure gold coatings drops sharply to about 45% at 1000℃, which cannot meet the requirements of high-temperature processes. This invention effectively solves the defect of poor high-temperature resistance of gold coatings and can be adapted to various high-temperature processes in semiconductor manufacturing.

[0020] By optimizing the slurry composition ratio and sintering process, the coating achieves a relative reflectivity of over 90% in the 800-2000nm infrared band. This efficiently reflects infrared heat, reducing heat loss from the quartz glass substrate and resulting in a more uniform temperature distribution within the reaction chamber. Furthermore, the coating's infrared reflectivity is minimally affected by temperature, exhibiting only slight reflectivity decay over long-term use. This ensures sustained energy savings and precise temperature control, thereby improving the yield and stability of chip manufacturing.

[0021] The raw materials used in this invention are all non-metallic, and no metal elements are introduced into the entire process, ensuring the high purity of the quartz glass substrate and fully meeting the purity requirements of the semiconductor industry for quartz glass components. Compared with existing doping modification technologies, this invention avoids the risk of metal impurities contaminating the semiconductor process and is applicable to quartz glass components throughout the entire semiconductor process. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a comparison of the relative reflectance of the quartz glass product obtained in Example 1 of the present invention before and after heat preservation at 1000℃ for 1 hour; Figure 2 This is a comparison of the relative reflectance of the quartz glass product obtained in Example 2 of the present invention before and after heat preservation at 1000℃ for 1 hour; Figure 3 This is a comparison of the relative reflectance of the quartz glass product obtained in Example 3 of the present invention before and after heat preservation at 1000℃ for 1 hour; Figure 4 This is a comparison of the relative reflectance of the quartz glass product obtained in Comparative Example 1 of this invention before and after heat preservation at 1000℃ for 1 hour; Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0026] A method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity, the method comprising the following steps: (1) Preparation of aqueous dispersion: Mix deionized water, ethylene glycol, polyethylene glycol and water-reducing agent evenly according to the set mass percentage. Among them, polyethylene glycol can improve the molding stability of the slurry as a binder, ethylene glycol can adjust the viscosity and fluidity of the dispersion, and water-reducing agent can enhance the dispersion performance of solid particles in the slurry, avoid particle agglomeration, and ensure the uniformity of the slurry.

[0027] (2) Preparation of coating slurry: Quartz glass micro powder, hydrophilic fumed silica particles, non-metallic sintering aid and aqueous dispersion obtained in step (1) are mixed in a set ratio, and then placed in a ball mill jar with grinding balls for ball milling. Ball milling can improve the sintering activity of particles, making it easier for the slurry layer to form a dense structure in the subsequent sintering process, while ensuring that the components are mixed evenly.

[0028] (3) Hydrophilic treatment of quartz glass substrate surface: First, the quartz glass is ultrasonically cleaned and dried with deionized water and alcohol to remove surface oil, impurities and other contaminants; then it is plasma treated to enhance the hydrophilicity and activity of the quartz glass surface through the activation effect of plasma, thereby enhancing the bonding force between the subsequent slurry layer and the substrate and preventing the coating from falling off.

[0029] (4) Coating of slurry layer: The slurry obtained in step (2) is coated on the surface of the quartz glass substrate after step (3) using a suitable coating method. After coating, the substrate is dried to remove moisture and volatile components from the slurry and form a stable solid slurry layer.

[0030] (5) Sintering of the slurry layer: The quartz glass treated in step (4) is subjected to high-temperature heat treatment. The specific process is as follows: the quartz glass is heated from room temperature to 100°C and kept at that temperature to further remove residual moisture in the slurry layer; then the temperature is raised to 500°C and kept at that temperature to remove organic components (such as polyethylene glycol) in the slurry; then the temperature is raised to 800°C and kept at that temperature to initially promote the bonding between particles; then the temperature is raised to 1000°C and kept at that temperature to lay the foundation for subsequent densification sintering; finally the temperature is raised to the set sintering temperature and kept at that temperature to fully sinter and densify the slurry layer; then the temperature is lowered to 150°C in stages and cooled to room temperature with the furnace to finally form a high-temperature resistant coating.

[0031] It should be noted that the ratio of the aqueous dispersion is deionized water: ethylene glycol: polyethylene glycol: water-reducing agent = 50-70: 40-20: 8: 2wt%; where the water-reducing agent is polycarboxylate ammonium salt.

[0032] The polyethylene glycol used in the aqueous dispersion has a molecular weight of one or more of 600, 2000, and 6000 g / mol, with 2000 and 6000 g / mol being preferred.

[0033] The total silica content in the slurry is 50-70 wt%, more preferably 65 wt%-75 wt%.

[0034] The quartz glass powder in the slurry is high-purity amorphous quartz glass powder with a particle size of 100-350 mesh. The particle mass ratio of high-purity amorphous quartz glass micropowder to hydrophilic fumed silica particles in the slurry is 10:1-18:1.

[0035] The non-metallic sintering aid in the slurry is one or more of boric acid, boron oxide, boron carbide, silicon carbide, and silicon nitride, preferably boron oxide or boron carbide.

[0036] The amount of non-metallic sintering aid in the slurry is 2wt% to 10wt% of the total amount of silica particles. When the sintering aid is boron oxide, it is 8wt% and when the sintering aid is boron carbide, it is preferably 2wt%.

[0037] The ball milling speed is 200-350 rpm, preferably 250-300 rpm, and the ball milling time is 8-16 hours, preferably 12 hours.

[0038] The activation process for the quartz glass substrate surface is plasma cleaning activation, wherein the plasma cleaning power is 250-300W, preferably 280W, and the plasma cleaning activation time is 5-10min, preferably 8min.

[0039] The coating methods for slurry include brushing, scraping, spraying, and other methods.

[0040] The sintering temperature of the coating is 1000-1200℃, preferably 1100-1150℃, and the holding time is 1-3h, preferably 1h.

[0041] The coating prepared by this invention uses quartz glass micropowder and hydrophilic fumed silica particles as the main raw materials, combined with non-metallic sintering aids, to form a dense inorganic coating structure after high-temperature sintering. This coating can withstand temperatures above 1000℃, and after treatment at 1000℃, its infrared relative reflectivity can still remain above 90%, without cracking or peeling. In contrast, the reflectivity of traditional pure gold coatings drops sharply to about 45% at 1000℃, which cannot meet the requirements of high-temperature processes. This invention effectively solves the defect of poor high-temperature resistance of gold coatings and can be adapted to various high-temperature processes in semiconductor manufacturing.

[0042] To make the above-mentioned objectives, features and advantages of this method more apparent and understandable, the following examples and comparative examples will be used to describe in detail the method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity.

[0043] Example 1: This embodiment describes the process and effect of preparing a high-temperature resistant infrared reflective coating on the surface of quartz glass using the method of the present invention.

[0044] The method is as follows: Preparation of aqueous dispersion: Select 50g of deionized water, 40g of ethylene glycol, 8g of polyethylene glycol (PEG6000) with a molecular weight of 6000g / mol and 2g of polycarboxylic acid ammonium salt, mix them evenly and set aside.

[0045] Ethylene glycol, as a humectant, can adjust the viscosity of the dispersion and prevent the slurry from drying too quickly before coating; PEG6000, as a binder, has a large molecular weight and excellent bonding performance, which can improve the molding stability of the slurry after drying; and ammonium polycarboxylate, as a dispersant, can reduce the agglomeration force between particles, ensure the uniform dispersion of the subsequent slurry system, and make the slurry more uniform and easier to coat.

[0046] Preparation of coating slurry: Weigh 24g of 325-mesh high-purity amorphous quartz glass micro powder and 2g of hydrophilic fumed silica particles; add 14g of boron oxide as a non-metallic sintering aid; add 14g of the above-prepared aqueous dispersion, mix, place the mixture in a ball mill jar, add grinding balls, seal well, and place it in a planetary ball mill for ball milling at a speed of 250 rpm for 12 hours to obtain a slurry with a silica content of 65wt%.

[0047] During the ball milling process, the impact and grinding action of the grinding balls can refine the particle size and improve the surface activity of the particles, while making boron oxide uniformly dispersed in the slurry, laying the foundation for subsequent sintering and densification; 325-mesh quartz glass micro powder takes into account both coating density and processing fluidity, and hydrophilic fumed silica particles can enhance the wetting ability of the slurry and the substrate.

[0048] Hydrophilic treatment of quartz glass substrate surface: The quartz glass substrate is ultrasonically cleaned sequentially with deionized water and alcohol (power 280W, time 15 minutes) to remove surface oil, dust and other impurities; after cleaning, it is dried with high-purity nitrogen and placed in a plasma cleaner for 8 minutes at 280W power.

[0049] Plasma treatment can break the Si-O-Si bonds on the surface of quartz glass and introduce polar groups such as hydroxyl (-OH), which significantly improves the surface hydrophilicity, allowing the subsequent slurry coating to spread quickly and avoiding defects such as edge shrinkage and pinholes.

[0050] (4) Coating of slurry layer: The slurry after ball milling is coated on the surface of the hydrophilic quartz glass substrate by spraying. The spraying pressure is controlled at 0.3MPa and the spraying distance is 20cm to ensure uniform coating thickness. After coating, it is naturally dried for 24 hours to allow the moisture and volatile components in the slurry to evaporate slowly and form a stable solid slurry layer.

[0051] (5) Sintering of the slurry layer: The quartz glass with the solid slurry layer is placed in a high-temperature electric furnace and heat-treated according to the following steps: The temperature is increased from room temperature to 100°C at a rate of 1°C / min and held for 1 hour to further remove residual free moisture from the slurry. Then, the temperature is increased to 500°C at a rate of 10°C / min and held for 1 hour to completely decompose and remove organic components such as polyethylene glycol, preventing the carbonization of organic matter during high-temperature sintering from affecting the coating performance. The temperature is then increased to 800°C at a rate of 10°C / min, followed by an increase to 1000°C at a rate of 2°C / min. Finally, the temperature is increased to 1100°C at a rate of 1°C / min and held for 1 hour to allow boron oxide to act as a sintering aid, reducing the sintering temperature between particles, promoting particle diffusion and fusion, and forming a dense structure. The temperature is then decreased to 500°C at a rate of 1°C / min, followed by a decrease to 150°C at a rate of 2°C / min, and then cooled to room temperature with the furnace to finally obtain a quartz glass plate product with high temperature resistance and high infrared relative reflectivity.

[0052] The coating obtained in this embodiment has a smooth and flat surface, free from cracking and peeling. Testing showed that its relative reflectivity in the 800-2000nm infrared band is ≥90.4%. This high reflectivity stems from the dense structure of the coating; after high-temperature sintering, the quartz glass micropowder and fumed silica particles are fully integrated to form a continuous silica matrix, which strongly reflects infrared photons. The addition of boron oxide not only lowers the sintering temperature but also fills the tiny pores between particles, further improving the reflection efficiency.

[0053] like Figure 1As shown, in the high-temperature resistance test, after the sample was heat-treated in air at 1000℃ for 1 hour, the infrared relative reflectance was still ≥90.2%, with only a slight decrease, which is far superior to the traditional gold coating (the reflectance dropped to 45.4% after treatment at 1000℃). This is because the core component of the coating is silicon dioxide, which has a melting point as high as about 1713℃. It is chemically stable and will not undergo melting, oxidation, or other reactions at high temperatures, thus maintaining its structural integrity.

[0054] Furthermore, this embodiment uses an aqueous dispersion system, which eliminates the volatilization of organic solvents and is environmentally friendly; all raw materials are non-metallic, without introducing any metallic impurities, and the purity of the quartz glass substrate remains unchanged, fully meeting the strict requirements of the semiconductor industry for substrate purity; the spraying method is suitable for processing large-area, complex-shaped quartz glass components, resulting in high production efficiency.

[0055] Example 2: This embodiment describes the process and effect of preparing a high-temperature resistant infrared reflective coating on the surface of quartz glass using the method of the present invention.

[0056] The method is as follows: (1) Preparation of aqueous dispersion: Select 60g of deionized water, 30g of ethylene glycol, 8g of polyethylene glycol (PEG2000) with a molecular weight of 2000g / mol and 2g of polycarboxylic acid ammonium salt and mix them evenly.

[0057] Among them, PEG2000 has a moderate molecular weight, combining adhesion and fluidity, which allows the slurry to adhere better to the substrate surface during the coating process and is less prone to sagging; the higher proportion of deionized water can further improve the dispersibility of the slurry and facilitate brush coating.

[0058] (2) Preparation of coating slurry: Weigh 24g of 325-mesh high-purity amorphous quartz glass micro powder and 2g of hydrophilic fumed silica particles; add 2.08g of boron oxide as a non-metallic sintering aid; add 12.03g of the above aqueous dispersion, mix, place the mixture in a ball mill jar, add grinding balls, seal it well and place it in a planetary ball mill for ball milling treatment, ball milling at a speed of 280 rpm for 12 hours to obtain a slurry with a silica content of 68wt%.

[0059] Among these advantages, higher ball milling speed can further refine particles and improve slurry uniformity; a total silica content of 68% results in higher slurry solid content, making the coating thickness easier to control and giving it greater densification potential.

[0060] (3) Hydrophilic treatment of quartz glass substrate surface: Same as in Example 1, that is, after ultrasonic cleaning and drying with high-purity nitrogen, it is subjected to plasma treatment with 280W power for 8 minutes to ensure that the hydrophilicity of the substrate surface meets the standard.

[0061] (4) Coating of slurry layer: The slurry after ball milling is coated on the surface of quartz glass substrate by brushing. The brushing direction is consistent to avoid generating air bubbles. After coating, it is naturally dried for 24 hours to form a uniform solid slurry layer.

[0062] The brush coating method is simple to operate, requires no special equipment, is suitable for processing small batches of irregularly shaped quartz glass parts, and can precisely control the local thickness of the coating.

[0063] (5) Sintering of slurry layer: The sintering steps are as follows: The sample is further dried by heating from room temperature to 100℃ at 1℃ / min and holding for 1h, then heating to 500℃ at 10℃ / min and holding for 1h, then heating to 800℃ at 10℃ / min, then heating to 1000℃ at 2℃ / min, and finally heating to 1100℃ at 1℃ / min and holding for 1h, then cooling to 500℃ at 1℃ / min, then cooling to 150℃ at 2℃ / min, and then cooling to room temperature with the furnace to finally obtain a quartz glass plate product with high temperature resistance and high infrared relative reflectivity.

[0064] The coating obtained in this embodiment has no obvious brush marks on its surface and has a dense structure. Its relative reflectivity in the 800-2000nm infrared band is ≥91.6%, which is slightly higher than that in Example 1. This is due to the higher silica solid content, which makes the coating denser, the scattering and reflection paths of infrared photons more concentrated, and the reflection efficiency further improved.

[0065] like Figure 2 As shown, after heat treatment at 1000℃ for 1 hour, the infrared relative reflectance of the coating remained at 91.6%, without any attenuation, demonstrating superior high-temperature stability. This is because the brush coating method allows for more thorough contact between the slurry and the substrate, resulting in a stronger bond and reducing the likelihood of interfacial delamination at high temperatures. Simultaneously, the higher solids content reduces internal porosity in the coating, preventing performance degradation caused by pore expansion at high temperatures.

[0066] In practical applications, the brush coating process does not require complex equipment, has lower production costs, and is suitable for small-batch trial production in the laboratory or processing of irregularly shaped parts; the water-based dispersion system has no environmental pollution and meets the requirements of green production; the coating has no metallic impurities and can be directly used on core components such as semiconductor reaction chambers, which can effectively reduce heat loss, reduce energy consumption, and improve chip manufacturing yield.

[0067] Example 3: This embodiment describes the process and effect of preparing a high-temperature resistant infrared reflective coating on the surface of quartz glass using the method of the present invention.

[0068] The method is as follows: (1) Preparation of aqueous dispersion: Select 50g of deionized water, 40g of ethylene glycol, 8g of polyethylene glycol (PEG2000) with a molecular weight of 2000g / mol and 2g of polycarboxylic acid ammonium salt and mix them evenly.

[0069] The combination of PEG2000's fluidity advantage and the moisturizing effect of a high proportion of ethylene glycol can effectively prevent high-solids content slurries from drying out and clumping before coating.

[0070] (2) Preparation of coating slurry: Weigh 24g of 325-mesh high-purity amorphous quartz glass micro powder and 2g of hydrophilic fumed silica particles, add 2.08g of boron oxide as a non-metallic sintering aid; then add 8.66g of the above aqueous dispersion, mix, place the mixture in a ball mill jar, add grinding balls, seal it well and place it in a planetary ball mill for ball milling treatment, ball milling at 300 rpm for 12 hours to obtain a slurry with 75wt% silica content.

[0071] The high silica content of 75% brings the slurry solid content to its peak, resulting in closer contact between particles; the maximum ball milling speed of 300 rpm can refine the particles to the maximum extent, improve particle activity, and provide a guarantee for sintering densification.

[0072] (3) Hydrophilic treatment of quartz glass substrate surface: consistent with Examples 1 and 2, to ensure the hydrophilicity of the substrate surface.

[0073] (4) Coating of slurry layer: The slurry after ball milling is coated onto the surface of quartz glass substrate by scraping; after coating, it is naturally dried for 24 hours to remove moisture and volatile components.

[0074] Among them, the scraping method can precisely control the coating thickness, making it suitable for scenarios with strict requirements on coating thickness, and can avoid the uneven thickness problems that may occur with spraying and brushing.

[0075] (5) Sintering of slurry layer: The sample is placed in a high-temperature electric furnace and heated from room temperature to 100°C at 1°C / min and held for 1 hour. Then, the temperature is increased to 500°C at 10°C / min and held for 1 hour. Then, the temperature is increased to 800°C at 10°C / min and then increased to 1000°C at 2°C / min. Finally, the temperature is increased to 1150°C at 1°C / min and held for 1 hour. Then, the temperature is decreased to 500°C at 1°C / min and then decreased to 150°C at 2°C / min. Finally, the temperature is cooled to room temperature with the furnace to obtain a quartz glass plate product with high temperature resistance and high infrared relative reflectivity.

[0076] The sintering temperature of 1150℃ is higher than that of the previous two embodiments, which can further promote particle diffusion and fusion and improve the coating density.

[0077] The coating obtained in this embodiment has the highest density, a mirror-like surface, and no pores or defects were found. Its relative reflectance in the 800-2000nm infrared band is ≥92.8%, reaching the optimal level of this invention. The core reason for the high reflectance is that the high silica content of 75% results in a high particle density within the coating, a short infrared photon penetration path, and a high reflection probability; the high-temperature sintering at 1150℃ forms strong Si-O-Si covalent bonds between the particles, resulting in an exceptionally dense coating structure with almost no infrared photon transmission channels.

[0078] like Figure 3 As shown, after heat treatment at 1000℃ for 1 hour, the relative infrared reflectance of the coating still remained at 92.8%, with no attenuation, demonstrating optimal high-temperature stability. This is because the high-density coating effectively blocks the erosion of external factors such as oxygen and moisture, and its structure remains unchanged at high temperatures; at the same time, the coating thickness formed by the scraping method is uniform, and the thermal stress is evenly distributed, preventing cracking and peeling at high temperatures.

[0079] In terms of application scenarios, the coating of this embodiment is suitable for semiconductor core components with extremely high requirements for infrared reflectivity and high temperature resistance, such as wafer carriers and reaction chamber walls. Although the production cost is slightly higher than the previous two embodiments, it is still much lower than that of gold coating. It is also environmentally friendly and free of metal pollution, fully meeting the stringent requirements of the semiconductor industry.

[0080] Comparative Example 1 Gold-coated quartz glass products are obtained by spraying hydrophilicated quartz glass plates at room temperature under isobaric pressure, followed by drying and heat treatment, using commercially purchased gold pigments.

[0081] like Figure 4 As shown, the gold-coated quartz glass product obtained has a relative reflectance of ≥100.7% in the 800-2000nm range, and the relative reflectance of the obtained sample decreased to ≥45.4% after heat treatment at 1000℃ in air atmosphere for 1h.

[0082] Table 1 is compiled based on Examples 1-3 and Comparative Example 1. Table 1. Comparison of relative reflectance of quartz glass products before and after heat preservation in Examples 1-3 and Comparative Example 1. The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for manufacturing a high-temperature resistant coating on the surface of quartz glass with high infrared reflectivity, characterized in that, Includes the following steps: (1) Preparation of aqueous dispersion: Mix deionized water, ethylene glycol, polyethylene glycol and water-reducing agent evenly; (2) Preparation of coating slurry: Quartz glass micro powder, hydrophilic fumed silica particles, non-metallic sintering aid and aqueous dispersion obtained in step (1) are mixed and then placed in a ball mill jar with grinding balls for ball milling. (3) Hydrophilic treatment of quartz glass substrate surface: Clean and dry the quartz glass; Then perform plasma treatment; (4) Coating of slurry layer: The slurry obtained in step (2) is coated on the surface of the quartz glass substrate treated in step (3), and then dried; (5) Sintering of slurry layer: The quartz glass after step (4) is subjected to high temperature heat treatment to make the slurry layer sintered and dense, forming a high temperature resistant coating.

2. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (1), the aqueous dispersion is prepared by mass percentage as follows: 50-70% deionized water, 20-40% ethylene glycol, 8% polyethylene glycol, and 2% water-reducing agent.

3. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (1), the molecular weight of the polyethylene glycol is one or more of 600, 2000, and 6000 g / mol.

4. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (1), the water-reducing agent is a polycarboxylic acid ammonium salt dispersant.

5. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (2), the mass ratio of the quartz glass micro powder to the hydrophilic fumed silica particles is 10:1-18:

1.

6. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (2), the total silica content in the coating slurry is 50-75% by mass percentage.

7. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (2), the non-metallic sintering aid is one or more of boric acid, boron oxide, boron carbide, silicon carbide, and silicon nitride.

8. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (2), the non-metallic sintering aid is 2-10 wt% of the total amount of hydrophilic fumed silica particles.

9. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (2), the ball milling speed is 200-350 rpm and the ball milling time is 8-16 h.

10. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (3), the plasma treatment time is 5-10 min.

11. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 1, characterized in that, In step (5), the high-temperature heat treatment process is as follows: the quartz glass is heated from room temperature to 100°C and held at that temperature, then heated to 500°C and held at that temperature, then heated to 800°C, then heated to 1000°C, and finally heated to the sintering temperature and held at that temperature, and then cooled to 150°C in stages and cooled with the furnace.

12. The method for manufacturing a high-temperature resistant coating on a quartz glass surface with high infrared reflectivity as described in claim 11, characterized in that, In step (5), the sintering temperature is 1100-1150℃ and the holding time is 1-3h.

Images