阅读说明：本技术 一种碳化硅薄壁结构件的制备方法 (Preparation method of silicon carbide thin-wall structural member ) 是由 杨金 于 2019-11-22 设计创作，主要内容包括：本发明公开了一种碳化硅薄壁结构件的制备方法,包括以下步骤：S1、利用石墨基材制作模具；S2、采用化学气相沉积法在石墨基材表面生长碳化硅；S3、从工件的边缘处切割碳化硅包裹部分使内部的石墨基材重新裸露出来；S4、将工件中的石墨基材完全与氧气进行反应,获得固体碳化硅工件。本发明具有碳化硅薄壁结构件具有较高的纯度,有利于避免高温、污染、氧化、腐蚀等问题,有助于提高设备工艺能力和稳定性的优点。(The invention discloses a preparation method of a silicon carbide thin-wall structural member, which comprises the following steps: s1, manufacturing a mold by using the graphite substrate; s2, growing silicon carbide on the surface of the graphite substrate by adopting a chemical vapor deposition method; s3, cutting the silicon carbide wrapping part from the edge of the workpiece to expose the graphite substrate inside again; and S4, completely reacting the graphite base material in the workpiece with oxygen to obtain the solid silicon carbide workpiece. The silicon carbide thin-wall structural member has the advantages of higher purity, contribution to avoiding the problems of high temperature, pollution, oxidation, corrosion and the like, and contribution to improving the process capability and stability of equipment.)

1. A preparation method of a silicon carbide thin-wall structural member is characterized by comprising the following steps: the method comprises the following steps:

s1, manufacturing a mold by using the graphite substrate;

s2, growing silicon carbide on the surface of the graphite substrate by adopting a chemical vapor deposition method;

s3, cutting the silicon carbide wrapping part from the edge of the workpiece to expose the graphite substrate inside again;

and S4, completely reacting the graphite base material in the workpiece with oxygen to obtain the solid silicon carbide workpiece.

2. The method for preparing the silicon carbide thin-walled structure according to claim 1, wherein: the detailed step of S2 is:

s2.1, placing the graphite substrate into chemical vapor deposition equipment, and vacuumizing the chemical vapor deposition equipment and replacing gas;

s2.2, introducing nitrogen, preheating and heating to 600-800 ℃, wherein the heating rate is 1-15 ℃/min;

s2.3, introducing nitrogen and hydrogen, continuously heating to 1400-1600 ℃, wherein the heating rate is 1-10 ℃/min;

and S2.4, after the temperature field is stabilized, starting to introduce raw material gas, hydrogen and argon, and growing at a rate of 10-200 mu m/h.

3. The method for manufacturing a silicon carbide thin-walled structure according to claim 2, wherein: the detailed step of S2 further includes:

s2.5, cooling when the thickness of the silicon carbide grows to be 200-500 mu m, and rotating and/or inverting the workpiece;

s2.6, repeating the steps S2.1 to S2.5 until the total growth thickness of the silicon carbide reaches the target requirement.

4. The method for manufacturing a silicon carbide thin-walled structure according to claim 2, wherein: in step S2.4, the raw material gas is trichloromethylsilane.

5. The method for preparing the silicon carbide thin-walled structure according to claim 1, wherein: and step S4, placing the workpiece into a high-temperature oxidation furnace, heating to 900-1200 ℃, introducing oxygen, reacting the graphite substrate with the oxygen at high temperature, discharging generated carbon dioxide, and obtaining the solid silicon carbide workpiece after the graphite substrate completely reacts.

6. The method for producing a silicon carbide thin-walled structure according to any one of claims 1 to 5, characterized in that: further comprising the steps of:

and S5, polishing and grinding the solid silicon carbide workpiece and adjusting the secondary size according to the requirements of the target size and the surface topography.

7. The method for manufacturing a silicon carbide thin-walled structure according to claim 6, wherein: further comprising the steps of:

and S6, cleaning by using 10% hydrofluoric acid, and then washing by using ultrasonic waves and deionized water to obtain a finished product.

8. The method for producing a silicon carbide thin-walled structure according to any one of claims 1 to 5, characterized in that: in step S1, the graphite substrate has a thickness of 2-50 mm and a surface finish of 500-1000nm, and is purified after being processed into a mold.

Technical Field

The invention relates to a preparation method of an internal coating of semiconductor equipment, in particular to a preparation method of a silicon carbide thin-wall structural member.

Background

At present, in the field of semiconductor equipment, because various environments such as corrosive chemical atmosphere, high temperature, ionization, particle deposition and the like exist inside a reaction chamber of equipment, in order to improve the process capability and the process stability of the equipment, 214LD quartz pieces, reactive sintered silicon carbide ceramics and silicon carbide coated graphite are selected materials which are generally applied inside the reaction chamber of the equipment. Because the internal temperature of the reaction cavity of some equipment needs to reach or even exceed 1300 ℃, the traditional 214LD semiconductor grade quartz piece can be softened at high temperature and cannot meet the use requirement; the reactive sintered silicon carbide ceramic is formed by mixing and sintering additive materials such as silicon carbide powder, other binders and the like, the content of metal impurities of the materials is difficult to control, high-precision semiconductor devices are easily polluted, and the yield is caused to be problematic; the silicon carbide coating graphite has high purity and good high-temperature corrosion resistance, but under the impact of temperature rise and temperature drop, the coating is easy to fall off, so that the equipment process is unstable.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a preparation method of a silicon carbide thin-wall structural member, which has higher purity, is beneficial to avoiding the problems of high temperature, pollution, oxidation, corrosion and the like and is beneficial to improving the process capability and stability of equipment.

In order to solve the technical problems, the invention adopts the following technical scheme:

a preparation method of a silicon carbide thin-wall structural member comprises the following steps:

s1, manufacturing a mold by using the graphite substrate;

s2, growing silicon carbide on the surface of the graphite substrate by adopting a chemical vapor deposition method;

s3, cutting the silicon carbide wrapping part from the edge of the workpiece to expose the graphite substrate inside again;

and S4, completely reacting the graphite base material in the workpiece with oxygen to obtain the solid silicon carbide workpiece.

As a further improvement of the above technical solution: the detailed step of S2 is:

s2.1, placing the graphite substrate into chemical vapor deposition equipment, and vacuumizing the chemical vapor deposition equipment and replacing gas;

s2.2, introducing nitrogen, preheating and heating to 600-800 ℃, wherein the heating rate is 1-15 ℃/min;

s2.3, introducing nitrogen and hydrogen, continuously heating to 1400-1600 ℃, wherein the heating rate is 1-10 ℃/min;

and S2.4, after the temperature field is stabilized, starting to introduce raw material gas, hydrogen and argon, and growing at a rate of 10-200 mu m/h.

As a further improvement of the above technical solution: the detailed step of S2 further includes:

s2.5, cooling when the thickness of the silicon carbide grows to be 200-500 mu m, and rotating and/or inverting the workpiece;

s2.6, repeating the steps S2.1 to S2.5 until the total growth thickness of the silicon carbide reaches the target requirement.

As a further improvement of the above technical solution: in step S2.4, the raw material gas is trichloromethylsilane.

As a further improvement of the above technical solution: and step S4, placing the workpiece into a high-temperature oxidation furnace, heating to 900-1200 ℃, introducing oxygen, reacting the graphite substrate with the oxygen at high temperature, discharging generated carbon dioxide, and obtaining the solid silicon carbide workpiece after the graphite substrate completely reacts.

As a further improvement of the above technical solution: the preparation method of the silicon carbide thin-wall structural member further comprises the following steps: and S5, polishing and grinding the solid silicon carbide workpiece and adjusting the secondary size according to the requirements of the target size and the surface topography.

As a further improvement of the above technical solution: the preparation method of the silicon carbide thin-wall structural member further comprises the following steps: further comprising the steps of: and S6, cleaning by using 10% hydrofluoric acid, and then washing by using ultrasonic waves and deionized water to obtain a finished product.

In step S1 of the method for manufacturing a silicon carbide thin-walled structure, the graphite substrate has a thickness of 2-50 mm and a surface finish of 500-1000nm, and is purified after being processed into a mold.

Compared with the prior art, the invention has the advantages that: the invention discloses a preparation method of a silicon carbide thin-wall structural member, which adopts an all-solid-state deposition silicon carbide material to prepare the structural member, the purity can reach 99.9999 percent, metal impurities such as Fe, Al, Cu, Zn and the like can be reduced to ppb (parts per billion) level, the problems of high temperature, pollution, oxidation, corrosion, material strength and the like can be effectively avoided by combining the material characteristics of silicon carbide, and the method can be widely applied to key parts of SiC oxidation furnace equipment, SiC epitaxial equipment, high-temperature MOCVD equipment and the like, and the process capability and the process stability of the equipment are effectively improved.

Drawings

FIG. 1 is a schematic flow chart of a method for manufacturing a thin-walled silicon carbide structural member according to the present invention.

Fig. 2 is a schematic flow chart of the method for preparing the plane thin-wall structural member.

FIG. 3 is a schematic flow chart of the method for preparing the non-planar special-shaped thin-wall structural member.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples of the specification.

Fig. 1 to 3 show an embodiment of the present invention, and the method for manufacturing a thin-walled silicon carbide structural member of the embodiment includes the following steps:

s1, manufacturing a mold by using the graphite substrate;

planning the size, shape and processing of the graphite mould according to the size of the structural part required to be manufactured, wherein the graphite mould can be a plane equal-thickness thin plate structural part generally or a non-plane special-shaped structural part such as a cylindrical thin-wall tube, a bell-type crucible, an MOCVD (metal organic chemical vapor deposition) tray and the like; the dimension planning of the planar equal-thickness sheet structural member is to obtain two structural members with two reference surfaces symmetrical by respectively taking the surface of the graphite substrate as a reference and taking the outward growth thickness as the structural thickness dimension; the size planning of the non-planar special-shaped thin-wall structural member can be achieved by taking the inner surface or the outer surface of the graphite substrate as a reference and the inward or outward growth thickness as the structural thickness, and taking the structural member growing in the direction of the corresponding reference surface as the final product;

s2, growing silicon carbide on the surface of the graphite substrate by adopting a Chemical Vapor Deposition (CVD) method;

s3, cutting the silicon carbide wrapping part from the edge of the workpiece to expose the graphite substrate inside again;

and S4, completely reacting the graphite base material in the workpiece with oxygen to obtain the solid silicon carbide workpiece.

The preparation method of the silicon carbide thin-wall structural member adopts the all-solid-state deposition silicon carbide material to prepare the structural member, the purity can reach 99.9999 percent, the metal impurities of Fe, Al, Cu, Zn and the like can be reduced to ppb (parts per billion) level, the problems of high temperature, pollution, oxidation, corrosion, material strength and the like can be effectively avoided by combining the material characteristics of silicon carbide, and the method can be widely applied to the key parts of SiC oxidation furnace equipment, SiC epitaxial equipment, high-temperature MOCVD equipment and the like, and the equipment process capability and the process stability are effectively improved.

Further, in this embodiment, the detailed step of S2 is:

s2.1, placing the graphite substrate into chemical vapor deposition equipment, and vacuumizing the chemical vapor deposition equipment and replacing gas;

s2.2, introducing nitrogen, preheating and heating to 600-800 ℃, wherein the heating rate is 1-15 ℃/min;

s2.3, introducing nitrogen and hydrogen, continuously heating to 1400-1600 ℃, wherein the heating rate is 1-10 ℃/min;

s2.4, after the temperature field is stabilized, introducing raw material gases of trichloromethylsilane (or the like), hydrogen and argon, and growing at a rate of 10-200 mu m/h.

Further, in this embodiment, the detailed step of S2 further includes:

s2.5, cooling when the thickness of the silicon carbide grows to be 200-500 mu m, and rotating and/or inverting the workpiece;

s2.6, repeating the steps S2.1 to S2.5 until the total growth thickness of the silicon carbide reaches the target requirement. Namely, a mode of repeated growth is adopted for many times, the workpiece is rotated by a certain angle and inverted after each growth, and the silicon carbide films on the same surface of the workpiece are kept uniform everywhere and the silicon carbide films on the inner surface and the outer surface of the workpiece are kept uniform and consistent.

Furthermore, in this embodiment, in step S4, the workpiece is placed in a high temperature oxidation furnace, the temperature is raised to 900 to 1200 ℃, oxygen is introduced to react the graphite substrate with oxygen at a high temperature, carbon dioxide is generated and discharged, and the solid silicon carbide workpiece is obtained after the graphite substrate completely reacts.

Further, in this embodiment, the method for manufacturing a silicon carbide thin-walled structural member further includes the steps of:

and S5, polishing and grinding the solid silicon carbide workpiece and adjusting the secondary size according to the requirements of the target size and the surface topography.

Furthermore, in this embodiment, the method for manufacturing a silicon carbide thin-walled structural member further includes the steps of:

and S6, cleaning by using 10% hydrofluoric acid, and then washing by using ultrasonic waves and deionized water to obtain a finished product.

Further, in this embodiment, in step S1, the graphite substrate has a thickness of 2-50 mm and a surface finish of 500-1000nm, and is processed into a mold and then subjected to a purification treatment, such as a high temperature purification treatment.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.