阅读说明：本技术 一种反应烧结碳化硅大舟托的制备方法 (Preparation method of reaction sintered silicon carbide boat support ) 是由 王兴龙 赵金 皇甫丙臣 杨凯 王新波 于 2021-08-10 设计创作，主要内容包括：一种反应烧结碳化硅大舟托的制备方法,素坯分开制作,干燥后精加工,后进行拼接,拼接过程中需要使用工装,烧结过程的变形控制：使用工装进行约束,烧成后的使用白刚玉24-60目的材料进行粗喷,检测并标记有冷凝硅的地方,精细精品处理。本方案采用反应烧结碳化硅材料代替石英舟托盘,大大的延长了舟托的使用寿命,减少了停机更换频次；碳化硅材质较石英材质的强度高、导热性能好,对产品扩散性更好。素坯精细加工后进行卯榫结构拼接再烧结,使用石墨仿形工装进行支撑和约束,最终达到低成本生产高精度、高性能的反应烧结碳化硅材料的舟托。目前已在市场上批量应用。(A preparation method of a reaction sintering silicon carbide boat support comprises the following steps of separately manufacturing a biscuit, drying the biscuit, finely processing the biscuit, splicing the biscuit, using a tool in the splicing process, and controlling the deformation of the sintering process: restraining by using a tool, carrying out coarse spraying by using a white corundum 24-60 mesh material after sintering, detecting and marking a place with condensed silicon, and carrying out fine product treatment. According to the scheme, the quartz boat tray is replaced by the reaction sintered silicon carbide material, so that the service life of the boat tray is greatly prolonged, and the frequency of shutdown and replacement is reduced; the silicon carbide material has higher strength, better heat-conducting property and better product diffusivity than the quartz material. And after the biscuit is finely processed, the mortise and tenon structure is spliced and then sintered, and a graphite profiling tool is used for supporting and restraining, so that the boat support for producing the reaction sintered silicon carbide material with high precision and high performance at low cost is finally achieved. Is applied in batch in the market at present.)

1. A preparation method of a reaction sintering silicon carbide boat support is characterized by comprising the following steps: a

Step 1), weighing 55-90 parts of silicon carbide, 5-10 parts of graphite powder, 2-5 parts of carbon black and 2-4 parts of an auxiliary agent according to the mass part ratio, adding 5-15 parts of water after uniformly stirring, continuously stirring uniformly, and then aging to obtain pug;

step 2), putting the material obtained in the step 1) into a forming extrusion device, and extruding each part of the forming tray;

step 3), cutting each formed part according to the allowance, and then drying in a drying room to obtain a biscuit;

step 4), carrying out finish machining on the biscuit obtained in the step 3) by using a finishing carving machine;

step 5), using a tool to splice the biscuit, and using a mortise and tenon structure for splicing;

step 6), loading a fixed boat support biscuit by using a copying tool, adding 45-65% of metal silicon, and sintering at 1700-1750 ℃ according to a sintering process to obtain a sintered boat support;

and 7) carrying out coarse blasting on the boat support obtained in the step 6) by using a white corundum 24-60 mesh material, then carrying out rechecking, marking a place with condensed silicon, and carrying out fine blasting to obtain a finished large boat support of silicon carbide.

2. The method for preparing a reaction-sintered silicon carbide boat rest as claimed in claim 1, wherein the splicing is carried out by using slurry for preparing slurry.

3. The method of claim 1, wherein the profiling fixture is made of graphite.

4. The method of claim 1, wherein the additive is selected from the group consisting of polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone, and carboxymethylcellulose.

Technical Field

The invention belongs to the technical field of new reaction sintering silicon carbide materials, and particularly relates to a preparation method of a reaction sintering silicon carbide boat support.

Background

The reaction sintering big boat support is used on a photovoltaic semiconductor, a quartz boat is supported, a silicon wafer is placed on the quartz boat, the silicon wafer is used for a diffusion process, the quartz boat is easy to break in the using process, and the using times are few (the quartz boat needs to be replaced in 15 days).

At present, the service life of the silicon carbide boat can reach more than 3 years. However, the existing manufacturing method of the silicon carbide sample strip has the defects of extremely high required precision, easy deformation during sintering, high finished product strength and difficult processing.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a preparation method of a reaction sintering silicon carbide boat support, which solves the problem that the existing material is fragile, and simultaneously achieves the characteristics of producing the reaction sintering silicon carbide boat support with high precision and high performance at low cost.

In order to achieve the purpose, the invention adopts the technical scheme that:

a preparation method of a reaction sintering silicon carbide boat support comprises the following steps: a

Step 1), weighing 55-90 parts of silicon carbide, 5-10 parts of graphite powder, 2-5 parts of carbon black and 2-4 parts of an auxiliary agent according to the mass part ratio, adding 5-15 parts of water after uniformly stirring, continuously stirring uniformly, and then aging to obtain pug;

step 2), putting the material obtained in the step 1) into a forming extrusion device, and extruding each part of the forming tray;

step 3), cutting each formed part according to the allowance, and then drying in a drying room to obtain a biscuit;

step 4), carrying out finish machining on the biscuit obtained in the step 3) by using a finishing carving machine;

step 5), using a tool to splice the biscuit, and using a mortise and tenon structure for splicing;

step 6), loading a fixed boat support biscuit by using a copying tool, adding 45-65% of metal silicon, and sintering at 1700-1750 ℃ according to a sintering process to obtain a sintered boat support;

and 7) carrying out coarse blasting on the boat support obtained in the step 6) by using a white corundum 24-60 mesh material, then carrying out rechecking, marking a place with condensed silicon, and carrying out fine blasting to obtain a finished large boat support of silicon carbide.

The splicing adopts slurry bonding for manufacturing mud.

The profiling tool is made of graphite.

The auxiliary agent is polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone or carboxymethyl cellulose.

The invention has the beneficial effects that:

according to the scheme, the quartz boat tray is replaced by the reaction sintered silicon carbide material, so that the service life of the boat tray is greatly prolonged, and the frequency of shutdown and replacement is reduced; the silicon carbide material has higher strength, better heat-conducting property and better product diffusivity than the quartz material. But the reaction sintering silicon carbide finished product is extremely difficult to process, so the invention adopts the following steps: the invention uses the graphite profiling tool for supporting and restraining, and finally achieves the purpose of producing the boat support of the reaction sintering silicon carbide material with high precision and high performance at low cost. Is applied in batch in the market at present.

Drawings

FIG. 1 is a schematic view of a silicon carbide boat.

FIG. 2 is a schematic view of a silicon carbide boat holder assembly.

FIG. 3 is a graph of the polished surface of the example with a smooth surface, uniform texture, and no visible pores or silicon spots.

FIG. 4 is a 200-fold metallographic microstructure observation of the example.

FIG. 5 is a 500-fold metallographic microstructure observation of the example.

Detailed Description

The invention is further described with reference to the following figures and examples.

As shown in fig. 1 and 2, a method for preparing a reaction sintered silicon carbide boat support comprises the following steps: a

Step 1), weighing 55-90 parts of silicon carbide, 5-10 parts of graphite powder, 2-5 parts of carbon black and 2-4 parts of an auxiliary agent according to the mass part ratio, adding 5-15 parts of water after uniformly stirring, continuously stirring uniformly, and then aging to obtain pug;

step 2), putting the material obtained in the step 1) into a forming extrusion device, and extruding each part of the forming tray;

step 3), cutting each formed part according to the allowance, and then drying in a drying room to obtain a biscuit;

step 4), carrying out finish machining on the biscuit obtained in the step 3) by using a finishing carving machine;

step 5), using a tool to splice the biscuit, and using a mortise and tenon structure for splicing;

step 6), loading a fixed boat support biscuit by using a copying tool, adding 45-65% of metal silicon, and sintering at 1700-1750 ℃ according to a sintering process to obtain a sintered boat support;

and 7) carrying out coarse blasting on the boat support obtained in the step 6) by using a white corundum 24-60 mesh material, then carrying out rechecking, marking a place with condensed silicon, and carrying out fine blasting to obtain a finished large boat support of silicon carbide.

The splicing adopts slurry bonding for manufacturing mud.

The profiling tool is made of graphite.

The auxiliary agent is polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone or carboxymethyl cellulose.

Examples

The strength and fracture toughness of the test groups of 4 groups prepared according to the above material compositions and preparation methods are shown in the following table:

and taking the group with the best effect for detection:

the polished surface has smooth surface, uniform tissue and no visible pores or silicon spots as shown in figure 3. And (3) metallographic microstructure observation: the material is compact at 200 times and 500 times without obvious air holes and abnormal phenomena; the residual silicon content was about 16.27% by volume, see fig. 4, 5.

In conclusion, the silicon carbide boat support prepared by the method meets the technical requirements.