A fine burning process of OP ring for semiconductor epitaxy

Abstract

This invention belongs to the field of semiconductor technology, and particularly relates to a fine sintering process for OP rings used in semiconductor epitaxy, comprising the following steps: S1: Front-end pretreatment section, which sequentially includes OP material receiving, unloading, water jet cutting, surface grinding, MC fine machining, dewaxing and cleaning, boiling and cleaning, and front-end process inspection; S2: Fire processing core section, which sequentially includes fire processing cleaning, fine sintering, annealing, and final inspection. The fire processing cleaning process first uses a neutral strong degreasing agent for cleaning, and then uses a mixture of nitric acid and hydrofluoric acid for cleaning. The fine sintering process uses a fine sintering machine to generate a flame through the combustion of high-purity hydrogen and oxygen to perform a one-time continuous flame polishing and fine sintering of the OP ring; S3: Post-processing purification and packaging section, where the OP rings completed in S2 are cleaned and packaged. The product surface of this invention is free of impurities, improving the uniformity of fine sintering, enhancing the smoothness, flatness, surface roughness and uniformity of the product surface, and increasing the yield.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and particularly relates to a fine sintering process for OP rings used in semiconductor epitaxy. Background Technology

[0002] In semiconductor manufacturing, epitaxial growth is a core process for achieving semiconductor device performance. It involves growing single-crystal thin films with specific electrical properties, thickness, and crystal structure on a single-crystal substrate, directly determining the performance, reliability, and yield of semiconductor devices. As semiconductor devices evolve towards miniaturization, high performance, and advanced processes, the quality requirements for epitaxial layers are becoming increasingly stringent. The cleanliness of the epitaxial reaction chamber and the surface quality and structural stability of the accompanying quartz components are key factors in ensuring the quality of epitaxial layer growth.

[0003] The 12-inch opaque liner quartz wafer for semiconductor epitaxy is a core component of the epitaxial reactor. Made of white, opaque semiconductor quartz, it possesses excellent radiative and conductive heat insulation properties, making it a high-quality reflector for the epitaxial reactor. Located between the OP flanges of the upper and lower domes of the epitaxial reactor, it plays a crucial role in assembly and connection. The surface uniformity of sintering, the consistency of stress distribution, and the surface cleanliness of this wafer directly affect the operational status of the epitaxial reaction chamber. Uneven sintering and significant differences in roughness distribution can lead to impurities remaining in the reaction chamber, resulting in uneven epitaxial layer thickness and inconsistent doping concentration, thus reducing the epitaxial processing yield. Uneven internal stress distribution can easily cause cracking during use or processing. The high material cost per unit and high scrap rate result in significant production cost losses.

[0004] In existing technologies, the sintering process for 12-inch op-ring semiconductor epitaxial products employs a segmented, intermittent sintering method within an annealing furnace. Specifically, the entire op-ring is divided into quarter- to half segments, which are then placed into the annealing furnace in batches for sintering. This process suffers from significant intervals between sintering periods, the sintering environment is easily affected by changes in the furnace temperature field, and the overall processing time exceeds 8 hours. This existing process has the following unresolved technical drawbacks: 1. Poor surface firing uniformity and low product qualification rate: Intermittent firing in segments leads to inconsistent firing degree in different parts of the product, uneven surface roughness distribution, large consistency error, uneven stress distribution, easy cracking, low product qualification rate, and high scrap rate.

[0005] 2. Excessive surface impurities affect the quality of the epitaxial layer. The existing cleaning process is simple and cannot completely remove impurities such as grease, metal particles, and quartz fragments from the product surface. After fine sintering, impurities remain on the product surface, which can easily cause contamination of the epitaxial reaction chamber after assembly, resulting in a decline in the growth quality of the epitaxial layer. 3. Low processing efficiency, unable to achieve mass production: The total firing time for a single product exceeds 8 hours, and the product quality stability is poor, which cannot meet the domestic semiconductor market's demand for high-quality, large-volume, and stable supply of 12-inch OP large ring products.

[0006] Based on the shortcomings of the existing technology, the development of a fine sintering process that can improve the surface uniformity of 12-inch OP large ring products, eliminate internal stress, reduce scrap rate, improve surface cleanliness, and enable mass production has become an urgent need in the semiconductor quartz supporting product processing field. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned technical problems by providing a fine sintering process for OP rings used in semiconductor epitaxy, which improves the surface smoothness, flatness, surface roughness, and uniformity of the product, thereby increasing the yield rate.

[0008] In view of this, the present invention provides a fine sintering process for an OP ring used in semiconductor epitaxy, comprising the following steps: S1: Pre-processing section, which includes OP material receiving, unloading, water jet cutting, surface grinding, MC finishing, dewaxing and cleaning, boiling and cleaning, and pre-processing inspection. S2: Fire processing core section, which includes the fire processing engineering cleaning, fine firing, annealing and final inspection processes in sequence. The fire processing engineering cleaning process first uses a neutral strong degreasing agent to clean, and then uses a mixture of nitric acid and hydrofluoric acid to clean. The fine firing process uses a fine firing machine to generate a flame through the combustion of high-purity hydrogen and oxygen to perform one-time continuous flame polishing and fine firing of the OP ring. S3: Post-purification and packaging section, where the OP rings that have completed S2 are washed and packaged; In this technical solution, the cleaning process of the fire processing engineering uses a neutral and powerful degreasing detergent to thoroughly clean the entire surface of the product without any dead angles. This effectively decomposes various oily impurities adhering to the product surface, leaving no residue and not corroding the quartz product. After thoroughly removing the oily impurities, the product is rinsed clean with pure water. The nitric acid in the mixture of nitric acid and hydrofluoric acid can efficiently dissolve the metal particle impurities on the product surface, while the hydrofluoric acid can precisely remove the small quartz fragments on the product surface. The two work synergistically to achieve the complete removal of non-quartz impurities, solving the problem of impurity residue caused by incomplete cleaning in existing processes. The product surface is free of impurities, which not only improves the uniformity of fine sintering but also avoids contamination of the epitaxial reaction chamber after assembly, thus improving the growth quality of the semiconductor epitaxial layer from the source. The innovative one-time continuous hydrogen-oxygen flame sintering process significantly improves the uniformity of surface sintering. It abandons the traditional method of "segmented division + intermittent annealing furnace sintering" and uses high-purity hydrogen and oxygen to perform uninterrupted flame polishing and sintering on the entire ring of products, achieving a smooth and flat surface with a surface roughness consistency error of ≤0.08μm. This increases the product processing qualification rate from less than 70% to over 95%.

[0009] Furthermore, in S1, the boiling and washing process involves preparing a cleaning solution with a mass concentration of 5%-35% using UTACK powder and RP-28, and then boiling and washing the products for 5-30 minutes.

[0010] In this technical solution, oil stains and residual wax on the surface of OP quartz products can be washed away, achieving basic cleaning of the products.

[0011] Furthermore, in the cleaning process of the S2 fire processing engineering, the volume concentration of nitric acid in the mixture of nitric acid and hydrofluoric acid is 10%-20%, and the volume concentration of hydrofluoric acid is 5%-15%.

[0012] Furthermore, in the cleaning process of the S2 medium-fired processing project, the OP ring is immersed in a mixture of nitric acid and hydrofluoric acid for 5-30 minutes for cleaning.

[0013] This technical solution achieves the complete removal of metal particles and small quartz fragments from the surface of the product.

[0014] Furthermore, in the S2 fine sintering process, the one-time continuous hydrogen-oxygen flame fine sintering includes two continuous stages: precise temperature control at the heating start point and fine flame fine sintering. There is no processing interval between the two stages, and both stages use a flame formed by the combustion of high-purity hydrogen and oxygen for fine sintering.

[0015] Furthermore, in the S2 fine firing process, during the precise temperature control stage of the heating start point, the weakest point of the product's symmetrical structure is selected as the sole heating start point, and the heating temperature is controlled at 1080℃-1150℃, with heat preservation for 5-20 minutes.

[0016] This technical solution can reduce the initial stress of the product during fine firing and avoid cracking in the early stage of fine firing.

[0017] Furthermore, in the S2 fine firing process, during the refined flame firing stage, a combined torch and welding torch are used to form a uniform flame surface, and the fine firing flame temperature is controlled at 1720℃±50℃.

[0018] In this technical solution, the entire ring of the product is fully covered by flame polishing without dead angles or interruptions through the precise movement of the welding torch, so that the surface of the product is smooth and flat, and the uniformity of surface firing is improved.

[0019] Furthermore, the total time for the fine firing process in S2 does not exceed 3 hours.

[0020] Furthermore, in the S2 annealing process, a low-temperature annealing furnace is used, with the annealing temperature controlled at 1030℃-1080℃, and the temperature difference in the furnace during the annealing process ≤±5℃.

[0021] This technical solution can efficiently remove internal stress from a product while ensuring that the product structure does not deform, thereby improving the uniformity of stress distribution.

[0022] Furthermore, S3 sequentially includes degreasing and cleaning, pure water cleaning, nitric acid cleaning, pure water cleaning, HF cleaning, pure water cleaning, Class 1000 cleaning and packaging, and warehousing. The soaking time for nitric acid cleaning and HF cleaning is 5-30 minutes, and after each chemical cleaning step, pure water cleaning is used until no cleaning agent residue remains. Class 1000 cleaning and packaging is completed in a Class 1000 clean environment.

[0023] The beneficial effects of this invention are: 1. Improved cleaning process for heat treatment engineering to achieve thorough surface cleaning of products: A two-step method of neutral strong degreasing cleaning followed by precise cleaning with a mixture of nitric acid and hydrofluoric acid is adopted to thoroughly remove grease, metal particles, and small quartz fragments from the product surface, solving the problem of impurity residue caused by incomplete cleaning in existing processes; the absence of impurity residue on the product surface not only improves the uniformity of fine sintering but also avoids contamination of the epitaxial reaction chamber after assembly, thus improving the quality of semiconductor epitaxial layer growth from the source.

[0024] 2. The unique one-time continuous hydrogen-oxygen flame polishing process significantly improves the uniformity of surface polishing: Abandoning the segmented and intermittent polishing method, high-purity hydrogen and oxygen are used to perform uninterrupted flame polishing and polishing of the entire ring product. Combined with the precise flame control of the collection gun and welding gun, the surface of the product is smooth and flat, with a surface roughness consistency error of ≤0.08μm, increasing the product processing qualification rate from less than 70% to more than 95%.

[0025] 3. Precise temperature control combined with continuous processing achieves low-stress molding of products: Precise temperature control at the heating start point reduces initial stress, uninterrupted continuous fine firing avoids stress fluctuations, and precise low-temperature annealing in a high-purity annealing furnace removes residual stress. These three stress control methods achieve uniform distribution of internal stress in the products, reducing the product cracking and scrap rate from over 30% to below 5%. Based on a monthly output of 50EA, this can reduce scrap costs by 620,000 yuan and increase monthly output value by 2.53 million yuan, significantly reducing production costs.

[0026] 4. Significantly improved processing efficiency, enabling stable mass production: The total firing time of the product has been reduced from more than 8 hours under the existing technology to less than 3 hours. Furthermore, the process parameters of the core fire processing section have been standardized and made more precise, resulting in a significant improvement in product quality stability. This meets the domestic semiconductor market's demand for high-quality, large-volume, and stable supply of 12-inch OP large-ring products, and enhances the level of domestic processing of this type of semiconductor quartz supporting products. Attached Figure Description

[0027] Figure 1 This is a process flow diagram of the present invention; Figure 2 This is a schematic diagram of an OP ring; Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0029] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0030] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0031] It should be noted that in the description of this application, the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0032] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0033] A 12-inch op-ring semiconductor epitaxy process, comprising a front-end pretreatment section, a core heat treatment section, and a back-end purification and packaging section, with specific process steps and parameters for each section as follows: S1: Pre-processing section. The pre-processing section includes OP material requisition, material unloading, waterjet cutting, surface grinding, MC finishing, dewaxing and cleaning, boiling and cleaning, and pre-processing inspection. The specific processes for each step are as follows: OP Material Requisition: The production planner requisitions OP materials based on the product manufacturing number, processing drawings, and POR. The requisitioned material is white opaque semiconductor quartz OP material, which has excellent radiation and conduction insulation properties. The material type and purity meet the production requirements of 12-inch semiconductor epitaxial OP large ring products. Records are made after material requisition. Blanking: The OP material is initially blanked by crystal drilling and ring cutting to obtain a rough blank, ensuring that the dimensional allowance of the rough blank meets the requirements of subsequent processing; Waterjet cutting: The rough blank is processed to a rough machining state using waterjet cutting equipment to form a prototype of the product and ensure the basic dimensional accuracy of the prototype. Surface grinding (rough and fine): Rough grinding and fine grinding are performed in sequence to improve the flatness and thickness of the product prototype to the medium-finish state, ensuring the basic structural accuracy of the product. MC precision machining: The product is precision machined by the MC machining center to make the parts of the product meet the design precision machining dimensions and structural requirements, and meet the assembly standards; Dewaxing and cleaning: Cleaning with a special dewaxing agent removes the wax and wax residue that adhered to the surface of the product during the MC processing, thus preventing wax residue from affecting the subsequent cleaning effect; Boiling and cleaning: Use Jiuzhong Electric, UTACK powder and RP-28 to prepare a cleaning solution with a mass concentration of 5%-35%. Boil and clean the products for 5-30 minutes to thoroughly remove oil and residual wax from the surface of OP quartz products and achieve basic cleaning of the products. Pre-process inspection: The quality department conducts a comprehensive inspection and confirmation of the dimensions and geometric tolerances of the products completed in the cold working process. Only qualified products can enter the core fire processing section, thus controlling the product structural accuracy from the source.

[0034] S2: Fire processing core section, which includes the fire processing engineering cleaning, fine firing, annealing and final inspection processes in sequence. The fire processing engineering cleaning process first uses a neutral strong degreasing agent to clean, and then uses a mixture of nitric acid and hydrofluoric acid to clean. The fine firing process uses a fine firing machine to generate a flame through the combustion of high-purity hydrogen and oxygen to perform one-time continuous flame polishing and fine firing of the OP ring. Among them, the cleaning process of the fire processing engineering abandons the conventional single cleaning method and adopts a two-step cleaning process of neutral strong degreasing cleaning, followed by soaking and cleaning with a mixture of nitric acid and hydrofluoric acid. This process can completely remove grease, metal particles and small quartz fragments from the surface of the product, providing a high-cleanliness surface foundation for the subsequent fine firing process. The specific steps are: (1) Neutral strong degreasing cleaning: The product is cleaned with a neutral strong degreasing cleaning agent to remove oil and grease from the entire surface without dead corners. This cleaning agent can efficiently decompose various oily impurities attached to the surface of the product, and leaves no residue and is non-corrosive. After thoroughly removing grease and impurities from quartz products, rinse them with pure water. (2) Soak and clean with a mixture of nitric acid and hydrofluoric acid: Prepare a special mixed cleaning solution with a volume concentration of 10%-20% for nitric acid and 5%-15% for hydrofluoric acid. Soak and clean the products in the mixed cleaning solution for 5-30 minutes. Nitric acid can efficiently dissolve metal particle impurities on the surface of the products, and hydrofluoric acid can accurately remove small quartz particles from the surface of the products. The two work together to completely remove non-quartz impurities. After soaking, rinse with pure water until there is no acid residue on the surface of the products.

[0035] The fine firing process abandons the existing technology of "segmented division + intermittent fine firing in annealing furnace". Instead, it uses a flame formed by the combustion of high-purity hydrogen and oxygen to perform uninterrupted and full-coverage overall flame polishing and fine firing of 12-inch OP large ring products. The total fine firing time does not exceed 3 hours, which fundamentally solves the problems of poor uniformity and uneven stress caused by segmented fine firing. Specifically, it is divided into two continuous stages without any processing interval: (1) Precise temperature control at the heating start point: Select the weakest point of the symmetrical structure of the product as the only heating start point. Use a high-purity hydrogen and oxygen flame to heat the position at a temperature of 1080℃-1150℃ for 5-20 minutes. Through precise preheating at a single point, the local temperature of the product is gradually increased and the product temperature is reduced. The initial stress of fine firing avoids stress concentration cracking caused by sudden overall temperature rise, and lays the stress foundation for subsequent ring fine firing; (2) Refined flame fine firing: After the preheating at the heating start point is completed, the 39# collection gun is immediately used in conjunction with the 0 and 1 welding guns to form a uniform and stable flame surface, and the fine firing flame temperature is precisely controlled at 1720℃±50℃; through the uniform and precise movement of the welding gun, the entire ring of the product is fully covered, without dead angles and without interruption of flame polishing fine firing, so that the surface of the quartz product melts and flattens quickly, and the surface of the product is smooth and flat, greatly improving the surface fine firing uniformity; the entire fine firing process is a continuous operation without any pauses or intervals, avoiding stress unevenness caused by temperature fluctuations.

[0036] After precise temperature-controlled annealing and sintering, the product is immediately placed in a high-purity annealing furnace for low-temperature annealing. The annealing temperature is precisely controlled between 1030℃ and 1080℃, and the temperature difference in the furnace is controlled within ±5℃ during the annealing process. This annealing process can efficiently and uniformly remove residual stress inside the product while ensuring that the product structure does not deform, further improving the uniformity of stress distribution and fundamentally reducing the risk of product cracking.

[0037] The final inspection of the heat treatment process involves a comprehensive dimensional and visual inspection of the annealed products, with a focus on checking the surface smoothness, flatness, absence of cracks, and absence of impurities to ensure that the products are dimensionally and visually qualified and meet the final assembly requirements. Only qualified products can proceed to the subsequent purification and packaging section.

[0038] S3: Post-process purification and packaging section. The post-process purification and packaging section includes degreasing and washing, pure water washing, nitric acid washing, pure water washing, HF washing, pure water washing, Class 1000 cleaning and packaging, and warehousing. The soaking time for nitric acid washing and HF washing is 5-30 minutes, and pure water washing is used after each chemical cleaning step to thoroughly remove cleaning agent residues. Class 1000 cleaning and packaging is completed in a Class 1000 clean environment to avoid contamination by external impurities. Finally, the qualified packaged products are sent to the warehouse for storage.

[0039] The OP material used is all white opaque semiconductor quartz, and the specification is 12-inch semiconductor epitaxial OP large ring type, with a single piece material cost of 40,000 yuan; the surface roughness is detected by a laser roughness meter, and the average value and consistency error are calculated by taking the roughness values ​​of 5 different detection points on the product surface; the pass rate is the proportion of products that meet the requirements of size, appearance and surface quality after processing to the total number of processed products; the scrap rate is the proportion of scrapped products due to cracking to the total number of processed products.

[0040] Comparative Example 1 The 12-inch OP large-ring product was divided into four equal parts. Before heat treatment, it was only subjected to conventional degreasing and cleaning followed by 10 minutes of cleaning with hydrofluoric acid (10% concentration). Intermittent fine firing was performed in an annealing furnace at 1100℃, with 1-hour intervals between firing stages, for a total firing time of 8.5 hours. Annealing was carried out in a standard annealing furnace at 950℃, with a temperature difference of ±30℃ within the furnace. A total of 50 products were processed, and the relevant data were tested and statistically analyzed. The results are shown in Table 1.

[0041] Example 1 Pre-treatment section: Boiling and washing process with a cleaning solution concentration of 15% for 15 minutes; Core section of fire processing: After cleaning with a neutral, strong degreasing detergent, the fire processing process involves soaking and cleaning in a mixture of 15% nitric acid and 10% hydrofluoric acid for 15 minutes; the heating start point of the continuous hydrogen-oxygen flame fine firing is controlled at 1100℃ / 10 minutes, the fine flame fine firing temperature is 1720℃, and the total fine firing time is 2.5 hours; the precise temperature control annealing temperature is 1050℃; Post-processing purification and packaging: The soaking time for nitric acid washing and HF washing was 15 minutes each. A total of 50 products were processed, and the relevant data were tested and statistically analyzed. The results are shown in Table 1.

[0042] Example 2 Pre-treatment section: Boiling and washing process with a cleaning solution concentration of 5% for 30 minutes; Core section of fire processing: After cleaning with a neutral, strong degreasing detergent, the fire processing process involves soaking and cleaning with a mixture of 10% nitric acid and 5% hydrofluoric acid for 30 minutes; the heating start point of the continuous hydrogen-oxygen flame fine firing is controlled at 1080℃ for 20 minutes, the fine flame fine firing temperature is 1670℃, and the total fine firing time is 3 hours; the precise temperature control annealing temperature is 1030℃; Post-processing purification and packaging: Soaking time for both nitric acid washing and HF washing was 30 minutes. A total of 50 products were processed, and relevant data were tested and statistically analyzed. The results are shown in Table 1.

[0043] Example 3 Pre-treatment section: Boiling and washing process with a cleaning solution concentration of 35% for 5 minutes; Core section of fire processing: After cleaning with a neutral, strong degreasing detergent, the fire processing process involves soaking and cleaning in a mixture of 20% nitric acid and 15% hydrofluoric acid for 5 minutes; the heating start point of the continuous hydrogen-oxygen flame fine firing is controlled at 1150℃ for 5 minutes, the fine flame fine firing temperature is 1770℃, and the total fine firing time is 2 hours; the precise temperature control annealing temperature is 1080℃; Post-processing purification and packaging: Soaking time for both nitric acid washing and HF washing was 5 minutes. A total of 50 products were processed, and relevant data were tested and statistically analyzed. The results are shown in Table 1.

[0044] Table 1: Performance Data Comparison between Example 1 and Examples 1 to 3 The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A fine sintering process for an OP ring used in semiconductor epitaxy, characterized in that... This includes the following steps: S1: Pre-processing section, which includes OP material receiving, unloading, water jet cutting, surface grinding, MC finishing, dewaxing and cleaning, boiling and cleaning, and pre-processing inspection. S2: Fire processing core section, which includes the fire processing engineering cleaning, fine firing, annealing and final inspection processes in sequence. The fire processing engineering cleaning process first uses a neutral strong degreasing agent to clean, and then uses a mixture of nitric acid and hydrofluoric acid to clean. The fine firing process uses a fine firing machine to generate a flame through the combustion of high-purity hydrogen and oxygen to perform one-time continuous flame polishing and fine firing of the OP ring. S3: The post-purification and packaging section washes and packages the OP rings that have completed S2.

2. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, In S1, the boiling and washing process involves preparing a cleaning solution with a mass concentration of 5%-35% using UTACK powder and RP-28, and then boiling and washing the products for 5-30 minutes.

3. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, In the cleaning process of S2 fire processing engineering, the volume concentration of nitric acid in the mixed solution of nitric acid and hydrofluoric acid is 10%-20%, and the volume concentration of hydrofluoric acid is 5%-15%.

4. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, In the cleaning process of the S2 medium-fired processing project, the OP ring is immersed in a mixture of nitric acid and hydrofluoric acid for 5-30 minutes.

5. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, In the S2 fine sintering process, the one-time continuous hydrogen-oxygen flame fine sintering includes two continuous stages: precise temperature control at the heating start point and fine flame fine sintering. There is no processing interval between the two stages, and both stages use a flame formed by the combustion of high-purity hydrogen and oxygen for fine sintering.

6. The sintering process for an OP ring used in semiconductor epitaxy according to claim 5, characterized in that, In the S2 fine firing process, during the precise temperature control stage of the heating start point, the weakest point of the product's symmetrical structure is selected as the sole heating start point, and the heating temperature is controlled at 1080℃-1150℃, with heat preservation for 5-20 minutes.

7. The sintering process for an OP ring used in semiconductor epitaxy according to claim 5, characterized in that, In the S2 fine firing process, during the refined flame firing stage, a combined torch and welding torch are used to form a uniform flame surface, and the fine firing flame temperature is controlled at 1720℃±50℃.

8. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, The total time for the fine firing process in S2 does not exceed 3 hours.

9. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, In the S2 annealing process, a low-temperature annealing furnace is used, with the annealing temperature controlled at 1030℃-1080℃. During the annealing process, the temperature difference in the furnace is ≤±5℃.

10. The sintering process for an OP ring used in semiconductor epitaxy according to claim 1, characterized in that, S3 sequentially includes degreasing and cleaning, pure water cleaning, nitric acid cleaning, pure water cleaning, HF cleaning, pure water cleaning, Class 1000 cleaning and packaging, and warehousing. The soaking time for nitric acid cleaning and HF cleaning is 5-30 minutes, and after each chemical cleaning step, pure water is used to clean until there is no cleaning agent residue. Class 1000 cleaning and packaging is completed in a Class 1000 clean environment.

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