阅读说明：本技术 一种高纯碳化硅制备方法及对应的高纯碳化硅 (Preparation method of high-purity silicon carbide and corresponding high-purity silicon carbide ) 是由 陈鹏磊 徐所成 王亚哲 姚秋鹏 程周鹏 皮孝东 于 2021-09-29 设计创作，主要内容包括：本申请公开了一种高纯碳化硅制备方法,包括以下步骤：S1、将高纯碳粉置于石墨坩埚内,使用高温真空的方法提纯高纯碳粉；S2、将块状硅放入石墨坩埚内,加热使块状硅融化,旋转石墨坩埚使高纯碳粉和块状硅混合均匀,反应合成高纯碳化硅。本申请使用块状硅代替硅粉,块状硅的纯度远高于硅粉末；在块状硅融化成液体硅后,通过石墨坩埚高速旋转,使硅溶液内部形成对流,高纯碳粉可均匀的分布在硅溶液中,冷却后可形成高纯度,高合成度的高纯碳化硅,高纯碳化硅的纯度普遍高于99.999％。(The application discloses a preparation method of high-purity silicon carbide, which comprises the following steps: s1, placing the high-purity carbon powder in a graphite crucible, and purifying the high-purity carbon powder by using a high-temperature vacuum method; and S2, putting the blocky silicon into a graphite crucible, heating to melt the blocky silicon, rotating the graphite crucible to uniformly mix the high-purity carbon powder and the blocky silicon, and reacting to synthesize the high-purity silicon carbide. According to the method, silicon powder is replaced by massive silicon, and the purity of the massive silicon is far higher than that of silicon powder; after the massive silicon is melted into liquid silicon, the graphite crucible rotates at a high speed, convection is formed inside the silicon solution, high-purity carbon powder can be uniformly distributed in the silicon solution, high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, and the purity of the high-purity silicon carbide is generally higher than 99.999%.)

1. The preparation method of the high-purity silicon carbide is characterized by comprising the following steps:

s1, placing the high-purity carbon powder in a graphite crucible, and purifying the high-purity carbon powder by using a high-temperature vacuum method;

and S2, putting the blocky silicon into a graphite crucible, heating to melt the blocky silicon, rotating the graphite crucible to uniformly mix the high-purity carbon powder and the blocky silicon, and reacting to synthesize the high-purity silicon carbide.

2. The method for preparing high purity silicon carbide according to claim 1, wherein the purity of the high purity carbon powder is 99.999% and the purity of the bulk silicon is 12N to 13N.

3. The method for producing high purity silicon carbide according to claim 1, wherein the step S1 includes the steps of:

s11, placing the graphite crucible in a heating furnace with a heat insulation material, and placing high-purity carbon powder in the graphite crucible;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by using a heating furnace, heating the interior to 800-1200 ℃, then heating to more than 2000 ℃, and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is always kept below 10^ -3Pa in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set rate;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder.

4. The method for producing high purity silicon carbide according to claim 1, wherein the step S2 includes the steps of:

s21, placing the blocky silicon in a graphite crucible, and placing the blocky silicon and the purified carbon powder together, wherein the molar ratio of the blocky silicon to the purified carbon powder is 1: 1;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace, heating the interior to 1500-2000 ℃, and completely melting the bulk silicon;

s25, keeping the temperature unchanged, and rotating the graphite crucible for 2-5 hours at the speed of 5-50 prm;

and S26, continuously rotating the graphite crucible at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

5. The preparation method of the high-purity silicon carbide is characterized by comprising the following steps:

s1, placing the high-purity carbon powder in a graphite lifting crucible, and purifying the high-purity carbon powder by using a high-temperature vacuum method;

s2, placing the blocky silicon into a graphite crucible, heating to melt the blocky silicon, descending a graphite lifting crucible to mix purified high-purity carbon powder with the silicon, and rotating the graphite crucible and the graphite lifting crucible at a differential speed to mix the high-purity carbon powder with the blocky silicon, wherein the molar ratio of the high-purity carbon powder to the blocky silicon is 1: 1, lifting the graphite lifting crucible, and cooling to obtain the high-purity silicon carbide.

6. The method for preparing high purity silicon carbide according to claim 5, wherein the purity of the high purity carbon powder is 99.999%.

7. The method for producing high purity silicon carbide according to claim 5, wherein the bulk silicon has a purity of 12N to 13N.

8. The method for producing high purity silicon carbide according to claim 5, wherein the step S1 includes the steps of:

s11, placing a graphite crucible in a heating furnace with a heat insulation material, placing a graphite lifting crucible in the heating furnace and above the graphite crucible, and placing high-purity carbon powder in the graphite lifting crucible;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by using a heating furnace, heating the interior to 800-1200 ℃, then heating to more than 2000 ℃, and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is always kept below 10^ -3Pa in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set speed;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder.

9. The method for producing high purity silicon carbide according to claim 8, wherein the step S2 includes the steps of:

s21, placing the massive silicon in a graphite crucible;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace, heating the interior to 1500-2000 ℃, and completely melting the blocky silicon of the graphite crucible;

s25, maintaining the temperature unchanged, descending the graphite lifting crucible to mix the purified high-purity carbon powder with the silicon liquid, controlling the graphite crucible and the graphite lifting crucible to rotate at a speed of 5-50 prm for 1-3 h, wherein the rotation directions of the graphite crucible and the graphite lifting pot are opposite, and then moving the graphite lifting crucible upwards;

and S26, continuously rotating the graphite crucible at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

10. A high purity silicon carbide produced by the method of producing a high purity silicon carbide according to any one of claims 1 to 9.

Technical Field

The invention relates to the field of silicon carbide manufacturing, in particular to a preparation method of high-purity silicon carbide and corresponding high-purity silicon carbide.

Background

The development and progress of semiconductor materials are key technologies related to national fate and international influence. As one of the important representatives of the third generation semiconductor materials, the silicon carbide single crystal material becomes a great hot gate of the future semiconductor materials due to the characteristics of large forbidden band width, high saturated electron mobility, strong breakdown field, high thermal conductivity and the like; therefore, the synthesis of high-purity silicon carbide powder is one of the key technologies at core.

The mainstream synthesis method of high-purity silicon carbide powder at present mainly adopts a high-temperature self-propagating method and a gas phase method. The high-temperature self-propagating method is to utilize high temperature to give initial heat to reactants to start chemical reaction, and then utilize self chemical reaction heat to enable unreacted substances to continue to complete the chemical reaction. However, since the chemical reaction of Si and C generates a small amount of heat, other additives must be added to maintain the self-propagating reaction, so that the introduction of impurity elements is inevitable, and the method is liable to cause reaction nonuniformity. The silicon carbide powder synthesized by the gas phase method has high purity and small particle size, but the synthesis method has high cost and low yield and is not suitable for batch production.

In addition to the above problems, the existing methods include the following drawbacks:

(1) the purity of the silicon powder is generally 6N and is far lower than 12N-13N of the bulk silicon raw material, so that the purity of the synthesized silicon carbide powder is lower and the purification difficulty is higher; at present, silicon powder and carbon powder are used for synthesizing silicon carbide powder, and the highest purity is 5N.

(2) In the existing method for synthesizing silicon carbide powder by using silicon powder and carbon powder, the silicon powder and the carbon powder are mixed by using a physical mixing method before reaction; the silicon powder and the carbon powder have non-uniform particle sizes, so that the physical mixing is difficult to achieve sufficient uniformity, and the silicon carbide powder synthesized by reaction is mixed with more unreacted carbon powder.

(3) At present, the silicon carbide powder generally needs high-temperature reaction at the temperature of more than 2000 ℃, consumes more energy and is not beneficial to environmental protection.

Disclosure of Invention

The invention overcomes at least one defect aiming at the problems and provides a preparation method of high-purity silicon carbide.

The technical scheme adopted by the invention is as follows:

a preparation method of high-purity silicon carbide comprises the following steps:

s1, placing the high-purity carbon powder in a graphite crucible, and purifying the high-purity carbon powder by using a high-temperature vacuum method;

and S2, putting the blocky silicon into a graphite crucible, heating to melt the blocky silicon, rotating the graphite crucible to uniformly mix the high-purity carbon powder and the blocky silicon, and reacting to synthesize the high-purity silicon carbide.

According to the method, silicon powder is replaced by massive silicon, and the purity of the massive silicon is far higher than that of silicon powder; after the massive silicon is melted into liquid silicon, the graphite crucible rotates at a high speed, convection is formed inside the silicon solution, high-purity carbon powder can be uniformly distributed in the silicon solution, high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, and the purity of the high-purity silicon carbide is generally higher than 99.999%.

In addition, the method is low in reaction temperature (the reaction temperature is lower than that of the existing synthesis method), simple in steps, and free of introducing dangerous and expensive gases such as hydrogen and silane during reaction, so that the method is beneficial to reducing cost, saving energy, reducing emission and protecting environment.

The purchased high purity carbon powder may cause variation in the content of impurities in the high purity carbon powder due to long-term storage and possible contamination during transportation. Before the high-purity carbon powder is used for synthesizing the raw material, the high-purity carbon powder is purified again, which is beneficial to reducing impurities of the synthetic raw material and improving the purity.

In one embodiment of the present invention, the purity of the high purity carbon powder is 99.999%.

In one embodiment of the present invention, the bulk silicon has a purity of 12N to 13N.

N is a few "9" in percent purity, e.g., 99.999% indicates a purity of 5N.

In one embodiment of the present invention, the step S1 includes the following steps:

s11, placing the graphite crucible in a heating furnace with a heat insulation material, and placing high-purity carbon powder in the graphite crucible;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by using a heating furnace, heating the interior to 800-1200 ℃, then heating to more than 2000 ℃, and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is always kept below 10^ -3Pa in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set speed;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder.

In S13, it is preferable that the pressure is always kept at 10^ -3Pa or less. In practice, the inert gas may be argon. The set rate of S14 may be a rate of natural cooling.

In one embodiment of the present invention, the step S2 includes the following steps:

s21, placing the blocky silicon in a graphite crucible, and placing the blocky silicon and the purified carbon powder together, wherein the molar ratio of the blocky silicon to the purified carbon powder is 1: 1;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace, heating the interior to 1500-2000 ℃, and completely melting the bulk silicon;

s25, keeping the temperature unchanged, and rotating the graphite crucible for 2-5 hours at the speed of 5-50 prm;

and S26, continuously rotating the graphite crucible at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

prm means revolutions per minute; in practical application, the high-purity silicon carbide obtained from S26 can be ground by a grinder to obtain high-purity silicon carbide powder, and the high-purity silicon carbide powder can provide powder for PVT method silicon carbide single crystal growth.

In practice, the rotation may be reciprocating for better mixing.

During actual use, the graphite crucible can be driven to rotate by the rotary supporting mechanism, and even the graphite crucible can be driven to rotate by driving the heating furnace to rotate.

The application also discloses another preparation method of high-purity silicon carbide, which comprises the following steps:

s1, placing the high-purity carbon powder in a graphite lifting crucible, and purifying the high-purity carbon powder by using a high-temperature vacuum method;

s2, placing the blocky silicon into a graphite crucible, heating to melt the blocky silicon, descending the graphite lifting crucible to mix the purified high-purity carbon powder with the silicon, wherein the molar ratio of the high-purity carbon powder to the blocky silicon is 1: and 1, rotating the graphite crucible and the graphite lifting crucible at a differential speed to mix high-purity carbon powder and massive silicon, lifting the graphite lifting crucible, and cooling to obtain the high-purity silicon carbide.

According to the method, silicon powder is replaced by massive silicon, and the purity of the massive silicon is far higher than that of silicon powder; after the massive silicon is melted into liquid silicon, convection can be formed inside the silicon solution through high-speed rotation of the graphite crucible and the graphite lifting crucible, high-purity carbon powder can be uniformly distributed in the silicon solution, high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, and the purity of the high-purity silicon carbide is generally higher than 99.999%.

In one embodiment of the present invention, the purity of the high purity carbon powder is 99.999%.

In one embodiment of the present invention, the bulk silicon has a purity of 12N to 13N.

In one embodiment of the present invention, the step S1 includes the following steps:

s11, placing a graphite crucible in a heating furnace with a heat insulation material, placing a graphite lifting crucible in the heating furnace and above the graphite crucible, and placing high-purity carbon powder in the graphite lifting crucible;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by using a heating furnace, heating the interior to 800-1200 ℃, then heating to more than 2000 ℃, and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is always kept below 10^ -3Pa in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set rate;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder.

In one embodiment of the present invention, the step S2 includes the following steps:

s21, placing the massive silicon in a graphite crucible;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace, heating the interior to 1500-2000 ℃, and completely melting the blocky silicon of the graphite crucible;

s25, maintaining the temperature unchanged, descending the graphite lifting crucible to mix the purified high-purity carbon powder with the silicon liquid, controlling the graphite crucible and the graphite lifting crucible to rotate at a speed of 5-50 prm for 1-3 h, wherein the rotation directions of the graphite crucible and the graphite lifting pot are opposite, and then moving the graphite lifting crucible upwards;

and S26, continuously rotating the graphite crucible at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

In practice, the rotation may be reciprocating for better mixing.

During actual use, the graphite crucible can be driven to rotate by the rotary supporting mechanism, and even the graphite crucible can be driven to rotate by driving the heating furnace to rotate.

The application also discloses the high-purity silicon carbide prepared by the preparation method.

The invention has the beneficial effects that: according to the method, silicon powder is replaced by massive silicon, and the purity of the massive silicon is far higher than that of silicon powder; after the massive silicon is melted into liquid silicon, the graphite crucible rotates at a high speed, convection is formed inside the silicon solution, high-purity carbon powder can be uniformly distributed in the silicon solution, high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, and the purity of the high-purity silicon carbide is generally higher than 99.999%.

Description of the drawings:

FIG. 1 is a schematic diagram of a process for producing high purity silicon carbide according to example 1;

FIG. 2 is a schematic view of a process for producing high purity silicon carbide according to example 2.

The figures are numbered:

1. a thermal insulation material; 2. lifting the crucible by graphite; 3. a graphite crucible; 4. high-purity carbon powder; 5. bulk silicon; 6. and a rotation supporting mechanism.

The specific implementation mode is as follows:

the present invention will be described in detail below with reference to the accompanying drawings.

Example 1

As shown in fig. 1, a method for preparing high purity silicon carbide comprises the following steps:

s1, placing the high-purity carbon powder 4 in a graphite crucible 3, and purifying the high-purity carbon powder 4 by using a high-temperature vacuum method;

s2, putting the blocky silicon 5 into the graphite crucible 3, heating to melt the blocky silicon 5, rotating the graphite crucible 3 to uniformly mix the high-purity carbon powder 4 and the blocky silicon 5, and reacting to synthesize the high-purity silicon carbide.

According to the method, the silicon powder is replaced by the massive silicon 5, and the purity of the massive silicon 5 is far higher than that of the silicon powder; after the massive silicon 5 is melted into liquid silicon, the graphite crucible 3 rotates at a high speed to form convection in the silicon solution, high-purity carbon powder 4 can be uniformly distributed in the silicon solution, and high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, wherein the purity of the high-purity silicon carbide is generally higher than 99.999%.

In addition, the method is low in reaction temperature (the reaction temperature is lower than that of the existing synthesis method), simple in steps, and free of introducing dangerous and expensive gases such as hydrogen and silane during reaction, so that the method is beneficial to reducing cost, saving energy, reducing emission and protecting environment.

The purchased high purity carbon powder may cause variation in the content of impurities in the high purity carbon powder due to long-term storage and possible contamination during transportation. Before the high-purity carbon powder is used for synthesizing the raw material, the high-purity carbon powder is purified again, which is beneficial to reducing impurities of the synthetic raw material and improving the purity.

In this embodiment, the purity of the high purity carbon powder 4 is 99.999%.

In this example, the purity of bulk silicon 5 is 12N to 13N.

N is a few "9" in percent purity, e.g., 99.999% indicates a purity of 5N.

In this embodiment, step S1 includes the following steps:

s11, placing the graphite crucible 3 in a heating furnace with a heat insulation material 1, and placing high-purity carbon powder 4 in the graphite crucible 3;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by a heating furnace, heating the interior to 800-1200 ℃ (preferably 1000 ℃), then heating to more than 2000 ℃ (preferably 2000 ℃) and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is kept below 10^ -3Pa all the time in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set speed;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder 4.

In S13, it is preferable that the pressure is always kept at 10^ -3Pa or less. In practice, the inert gas may be argon. The set rate of S14 may be a rate of natural cooling.

In this embodiment, step S2 includes the following steps:

s21, placing the block silicon 5 in the graphite crucible 3, and placing the block silicon and the purified carbon powder together, wherein the molar ratio of the block silicon to the purified carbon powder is 1: 1;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace to raise the temperature inside to 1500-2000 ℃ so as to completely melt the massive silicon 5;

s25, keeping the temperature unchanged, and rotating the graphite crucible 3 at the speed of 5-50 prm for 2-5 h;

and S26, continuously rotating the graphite crucible 3 at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

prm means revolutions per minute; in practical use, the high-purity silicon carbide obtained in S26 can be pulverized by a pulverizer to obtain high-purity silicon carbide powder, and the high-purity silicon carbide powder can provide powder for PVT method silicon carbide single crystal growth.

In practice, the rotation may be reciprocating for better mixing.

During practical use, the graphite crucible 3 can be driven to rotate by rotating the supporting mechanism 6, and even the graphite crucible 3 can be driven to rotate by driving the heating furnace to rotate.

The embodiment also discloses the high-purity silicon carbide prepared by the preparation method of the high-purity silicon carbide.

Example 2

As shown in fig. 2, the present embodiment discloses a method for preparing high purity silicon carbide, which comprises the following steps:

s1, placing the high-purity carbon powder 4 in a graphite lifting crucible 2, and purifying the high-purity carbon powder 4 by using a high-temperature vacuum method;

s2, placing the blocky silicon 5 into the graphite crucible 3, heating to melt the blocky silicon 5, descending the graphite lifting crucible 2 to mix the purified high-purity carbon powder 4 with the silicon, rotating the graphite crucible 3 and the graphite lifting crucible 2 to mix the high-purity carbon powder 4 with the blocky silicon 5, wherein the molar ratio of the high-purity carbon powder to the blocky silicon is 1: 1, lifting the graphite lifting crucible 2, and cooling to obtain the high-purity silicon carbide.

According to the method, the silicon powder is replaced by the massive silicon 5, and the purity of the massive silicon 5 is far higher than that of the silicon powder; after the massive silicon 5 is melted into liquid silicon, convection can be formed inside the silicon solution through high-speed rotation of the graphite crucible 3 and the graphite lifting crucible 2, high-purity carbon powder 4 can be uniformly distributed in the silicon solution, high-purity silicon carbide with high purity and high synthesis degree can be formed after cooling, and the purity of the high-purity silicon carbide is generally higher than 99.999%.

In this embodiment, the purity of the high purity carbon powder 4 is 99.999%.

In this example, the purity of bulk silicon 5 is 12N to 13N.

In this embodiment, step S1 includes the following steps:

s11, placing a graphite crucible 3 in a heating furnace with a heat insulation material 1, placing a graphite lifting crucible 2 in the heating furnace and above the graphite crucible 3, and placing high-purity carbon powder 4 in the graphite lifting crucible 2;

s12, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s13, heating by a heating furnace, heating the interior to 800-1200 ℃ (preferably 1000 ℃), then heating to more than 2000 ℃ (preferably 2000 ℃) and keeping for 5-10 h, wherein the vacuum degree of the heating furnace is kept below 10^ -3Pa all the time in the heating process;

s14, cooling the interior of the heating furnace to room temperature at a set speed;

and S15, after the temperature reduction is finished, introducing inert gas into the heating furnace to carry out back pressure protection on the high-purity carbon powder 4.

In this embodiment, step S2 includes the following steps:

s21, placing the block-shaped silicon 5 in the graphite crucible 3;

s22, vacuumizing the heating furnace to 10^ -6Pa under the state of a cold furnace;

s23, introducing inert gas into the heating furnace until the pressure in the heating furnace rises to 0.5-1.1 atm;

s24, heating by a heating furnace to raise the temperature inside to 1500-2000 ℃ so as to completely melt the blocky silicon 5 of the graphite crucible 3;

s25, maintaining the temperature unchanged, descending the graphite lifting crucible 2 to mix the purified high-purity carbon powder 4 with the silicon liquid, controlling the graphite crucible 3 and the graphite lifting crucible 2 to rotate at the speed of 5-50 prm for 1-3 h, wherein the rotation directions of the graphite crucible 3 and the graphite lifting crucible are opposite, and then moving the graphite lifting crucible 2 upwards;

and S26, continuously rotating the graphite crucible 3 at the speed of 5-50 prm, and cooling the heating furnace to room temperature to obtain the high-purity silicon carbide.

In this embodiment, the graphite crucible 3 and the graphite lifting pot rotate in opposite directions, and the stirring effect is the best. In other embodiments, one of the graphite crucible 3 and the graphite lifting pot may rotate, and the other may not rotate, to perform stirring.

In practice, the rotation may be reciprocating for better mixing.

During practical use, the graphite crucible 3 can be driven to rotate by rotating the supporting mechanism 6, and even the graphite crucible 3 can be driven to rotate by driving the heating furnace to rotate.

The embodiment also discloses the high-purity silicon carbide prepared by the preparation method of the high-purity silicon carbide.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent structural changes made by using the contents of the present specification and the drawings, which are directly or indirectly applied to other related technical fields, are included in the scope of the present invention.