Growth furnace for growing silicon carbide single crystal by PVT method
By introducing an adjustable regulating plate and aluminosilicate fiber insulation into the silicon carbide single crystal growth furnace, the problem that existing technologies can only produce crystals of a single size has been solved, realizing the flexibility of multi-size production and high-quality growth, while reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2026-03-10
AI Technical Summary
Existing silicon carbide single crystal growth furnaces can only produce crystals of a single size, which limits production efficiency and flexibility.
A growth furnace for growing silicon carbide single crystals using the PVT method was designed. It adopts an adjustable regulating plate and aluminosilicate fiber insulation, which can adapt to the production needs of eight-inch or six-inch crystals. The seed crystal position and angle are adjusted by a rotary motor and a hydraulic telescopic rod, and the crystal growth conditions are optimized by combining induction coil heating.
It improves production flexibility and crystal growth quality, reduces production costs, ensures the stability and accuracy of seed crystals during the growth process, and enhances thermal efficiency and temperature uniformity.
Smart Images
Figure CN223983756U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to silicon carbide production technical field, and specifically relates to a growth furnace for PVT method silicon carbide single crystal growth. BACKGROUND
[0002] Silicon carbide is a kind of wide band gap semiconductor material, because its excellent physical and chemical properties, such as high hardness, high melting point, high thermal conductivity and excellent radiation resistance, is widely used in electronic, photoelectric, photovoltaic and high-temperature structural material and other fields, especially in high-temperature, high-frequency, high-power electronic devices, silicon carbide material shows huge application potential, physical gas phase transmission method (PVT method) is an important method for growing high-quality silicon carbide single crystal, this method is to make silicon carbide raw material sublimate at high temperature, then utilize carrier gas to transmit the sublimated silicon carbide to the area of lower temperature, and then make it recondense into crystal, this process needs to accurately control temperature, pressure, airflow and other parameters to ensure the quality and growth rate of crystal;
[0003] However, the existing growth furnace for silicon carbide single crystal has limitations in the use process, and can only produce single-size crystals, which greatly limits its production efficiency and flexibility, therefore, the utility model provides a growth furnace for PVT method silicon carbide single crystal growth. UTILITY MODEL CONTENT
[0004] The utility model aims at providing a growth furnace for PVT method silicon carbide single crystal growth to solve the problems in the above background.
[0005] To achieve the above object, the utility model provides the following technical scheme: a growth furnace for PVT method silicon carbide single crystal growth, including growth furnace frame, the outside fixed connection of growth furnace frame has top frame, the top of top frame is fixedly connected with rotating electrical machine, the output shaft of rotating electrical machine is fixedly connected with hydraulic telescopic rod, one side of hydraulic telescopic rod towards growth furnace frame is fixedly connected with seed crystal support, the top of seed crystal support is equipped with adjusting disc.
[0006] As a preferred implementation form, the bottom of the inner cavity of the growth furnace frame is fixedly connected with a quartz tube, the inside of the quartz tube is fixedly connected with an insulator, the inside of the insulator is fixedly connected with a graphite crucible, the bottom of the inner cavity of the graphite crucible is fixedly connected with a vapor source, and the vapor source is located directly below the seed crystal support.
[0007] As a preferred implementation form, an induction coil is arranged between the quartz tube and the growth furnace frame.
[0008] As a preferred implementation form, the material of the insulator is aluminum silicate fiber.
[0009] In a preferred embodiment, a seed crystal growth cavity is formed on the side of the seed crystal holder facing the gas source, a connecting groove is formed on the inner wall of the seed crystal growth cavity, and a limiting protrusion adapted to the connecting groove is formed on the outside of the adjusting disk.
[0010] In a preferred embodiment, the limiting protrusion has a deformation cavity inside, the adjusting disk is annular, and the inner wall of the adjusting disk has a sealing angle at the edge that contacts the seed crystal growth cavity.
[0011] In a preferred embodiment, the bottom of the adjustment disc has two force-applying grooves.
[0012] Compared with the prior art, the beneficial effects of this utility model are:
[0013] The growth furnace for growing silicon carbide single crystals using the PVT method can be equipped with an adjustment plate, which can be disassembled and installed according to the production needs of eight-inch or six-inch crystals. Simply replace the adjustment plate of the appropriate size to ensure the stability and accuracy of the seed crystal during the growth process. This design not only improves production flexibility but also reduces production costs because there is no need to purchase completely different growth furnaces for silicon carbide single crystals of different sizes.
[0014] The growth furnace for growing silicon carbide single crystals using the PVT method employs aluminosilicate fiber as the insulation material. Aluminosilicate fiber has excellent high-temperature resistance and thermal insulation properties, which can effectively prevent heat transfer and improve the thermal efficiency and temperature uniformity of the growth furnace. At the same time, the design of the insulation material also optimizes the heat conduction path between the graphite crucible and the gas source, further improving the crystal growth quality. Attached Figure Description
[0015] Fig. 1 This is a front view of the structure of this utility model;
[0016] Fig. 2 This is a partial cross-sectional view of the structure of this utility model;
[0017] Fig. 3 This is a cross-sectional view of the seed crystal holder.
[0018] In the diagram: 1. Growth furnace frame; 2. Top frame; 3. Rotary motor; 4. Hydraulic telescopic rod; 5. Induction coil; 6. Insulation body; 7. Graphite crucible; 8. Gas source; 9. Seed crystal holder; 901. Seed crystal growth cavity; 902. Connecting groove; 903. Adjusting plate; 904. Limiting protrusion; 905. Deformation cavity; 906. Force application groove; 907. Sealing angle. Detailed Implementation
[0019] The present invention will be further described below with reference to the embodiments.
[0020] The following embodiments are used to illustrate the present invention, but should not be used to limit the scope of protection of the present invention. The conditions in the embodiments can be further adjusted according to specific conditions, and simple improvements to the method of the present invention under the premise of the concept of the present invention are all within the scope of protection claimed by the present invention.
[0021] Please see Figs. 1-3 This utility model provides a growth furnace for growing silicon carbide single crystals using the PVT method. It includes a furnace frame 1, a top frame 2 fixedly connected to the outside of the furnace frame 1, a rotary motor 3 fixedly connected to the top of the top frame 2, a hydraulic telescopic rod 4 fixedly connected to the output shaft of the rotary motor 3, a seed crystal holder 9 fixedly connected to the side of the hydraulic telescopic rod 4 facing the furnace frame 1, an adjustment plate 903 on the top of the seed crystal holder 9, a quartz tube fixedly connected to the bottom of the inner cavity of the furnace frame 1, an insulation body 6 fixedly connected inside the quartz tube, a graphite crucible 7 fixedly connected inside the insulation body 6, a gas source 8 fixedly connected to the bottom of the inner cavity of the graphite crucible 7, the gas source 8 being located directly below the seed crystal holder 9, and an induction coil 5 between the quartz tube and the furnace frame 1. An appropriate induction coil 5 is selected according to the required size of the silicon carbide single crystal to be produced. The adjusting plate 903 is installed on the seed crystal holder 9, ensuring that the seed crystal is correctly fixed on the adjusting plate 903. The induction coil 5 is activated, heating the graphite crucible 7 and the silicon carbide raw material therein through the principle of electromagnetic induction. As the temperature rises, the silicon carbide raw material begins to sublimate, forming a gas phase. The sublimated silicon carbide gas phase is transported to the seed crystal on the seed crystal holder 9 through the space inside the quartz tube under the action of the carrier gas. At the seed crystal on the seed crystal holder 9, the sublimated silicon carbide gas phase re-condenses into a crystal. Through the coordinated action of the rotary motor 3 and the hydraulic telescopic rod 4, the position, angle and height of the seed crystal can be adjusted, thereby optimizing the crystal growth conditions. When the crystal growth reaches the predetermined size and quality, the induction coil 5 is turned off, allowing the growth furnace to cool naturally or using a forced cooling method. After cooling, the growth furnace frame 1 is opened, and the grown silicon carbide single crystal is taken out.
[0022] Among them, the material of the heat insulation body 6 is aluminum silicate fiber. The use of aluminum silicate fiber as the material of the heat insulation body 6 has excellent high temperature resistance and heat insulation performance, which can effectively prevent heat transfer and improve the thermal efficiency and temperature uniformity of the growth furnace. At the same time, the design of the heat insulation body 6 also optimizes the heat conduction path between the graphite crucible 7 and the gas source 8, further improving the growth quality of the crystal.
[0023] In this embodiment, a seed crystal growth cavity 901 is formed on the side of the seed crystal holder 9 facing the gas source 8. A connecting groove 902 is formed on the inner wall of the seed crystal growth cavity 901. A limiting protrusion 904 adapted to the connecting groove 902 is formed on the outside of the adjusting disk 903. A deformation cavity 905 is formed inside the limiting protrusion 904. The adjusting disk 903 is annular. A sealing angle 907 is provided at the edge where the inner wall of the adjusting disk 903 contacts the seed crystal growth cavity 901. Two force-applying grooves 906 are formed at the bottom of the adjusting disk 903. According to the required silicon carbide single crystal size, a suitable adjusting disk 903 is selected. The limiting protrusion 904 of the adjusting disk 903 is aligned with the connecting groove 902 on the seed crystal holder 9, and gently rotated and pressed to make the adjusting disk 903 fit tightly with the seed crystal holder 9. During the installation process, the deformation cavity 905 undergoes slight deformation to adapt to the shape of the connecting groove 902, thereby ensuring the stable installation of the adjusting plate 903. The seed crystal is placed in the seed crystal growth chamber 901, ensuring that its contact surface with the adjusting plate 903 is flat and tight. By adjusting the position and angle of the adjusting plate 903, the growth conditions of the seed crystal can be further optimized. Following the previously described workflow, the heating, transmission, and condensation growth stages of the growth furnace are started. During the crystal growth process, the position, angle, and height of the seed crystal can be adjusted through the synergistic action of the rotary motor 3 and the hydraulic telescopic rod 4. When the crystal growth reaches the predetermined size and quality, the growth furnace is closed and allowed to cool naturally or by forced cooling. After cooling, the growth furnace frame 1 is opened, and the grown silicon carbide single crystal is taken out.
[0024] By setting the adjustment plate 903, the production of eight-inch or six-inch silicon carbide single crystals can be easily adjusted according to production needs. This reduces production costs because there is no need to purchase completely different growth furnaces for silicon carbide single crystals of different sizes. The tight fit between the adjustment plate 903 and the seed crystal holder 9, as well as the design of the sealing angle 907, ensures the stability of the seed crystal during the growth process, which helps to improve the growth quality and production efficiency of the crystal. The matching design of the limiting protrusion 904 and the connecting groove 902, as well as the setting of the deformation cavity 905 and the force application groove 906, make the disassembly and replacement of the adjustment plate 903 simple and quick, which reduces the difficulty of operation and time costs.
[0025] The working principle and usage process of this utility model are as follows: First, select a suitable adjusting plate 903 according to the required silicon carbide single crystal size. Align the limiting protrusion 904 of the adjusting plate 903 with the connecting groove 902 on the seed crystal holder 9, and gently rotate and press to ensure a tight fit between the adjusting plate 903 and the seed crystal holder 9. During installation, the deformation cavity 905 will undergo slight deformation to adapt to the shape of the connecting groove 902, thereby ensuring the stable installation of the adjusting plate 903. Place the seed crystal in the seed crystal growth cavity 901, ensuring that its contact surface with the adjusting plate 903 is flat and tight. By adjusting the position and angle of the adjusting plate 903, the growth conditions of the seed crystal can be further optimized. Start the induction coil 5. The graphite crucible 7 and the silicon carbide raw material therein are heated by electromagnetic induction. As the temperature rises, the silicon carbide raw material begins to sublimate and form a gas phase. The sublimated silicon carbide gas phase is transported to the seed crystal on the seed crystal holder 9 through the space inside the quartz tube under the action of the carrier gas. At the seed crystal on the seed crystal holder 9, the sublimated silicon carbide gas phase re-condenses into a crystal. Through the coordinated action of the rotary motor 3 and the hydraulic telescopic rod 4, the position, angle and height of the seed crystal can be adjusted, thereby optimizing the crystal growth conditions. When the crystal grows to the predetermined size and quality, the induction coil 5 is turned off, and the growth furnace is allowed to cool naturally or by forced cooling. After cooling, the growth furnace frame 1 is opened and the grown silicon carbide single crystal is taken out.
[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A growth furnace for growing silicon carbide single crystals by the PVT method, comprising a growth furnace frame (1), characterized in that: The outer part of the growth furnace frame (1) is fixedly connected with a top frame (2), the top of the top frame (2) is fixedly connected with a rotary motor (3), the output shaft of the rotary motor (3) is fixedly connected with a hydraulic telescopic rod (4), one side of the hydraulic telescopic rod (4) facing the growth furnace frame (1) is fixedly connected with a seed crystal holder (9), and the top of the seed crystal holder (9) is provided with an adjusting disc (903).
2. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 1, characterized in that: The bottom of the inner cavity of the growth furnace frame (1) is fixedly connected with a quartz tube, the inside of the quartz tube is fixedly connected with an insulator (6), the inside of the insulator (6) is fixedly connected with a graphite crucible (7), the bottom of the inner cavity of the graphite crucible (7) is fixedly connected with a gas phase source (8), and the gas phase source (8) is located directly below the seed crystal holder (9).
3. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 2, characterized in that: An induction coil (5) is arranged between the quartz tube and the growth furnace frame (1).
4. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 2, characterized in that: The material of the insulator (6) is aluminum silicate fiber.
5. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 2, characterized in that: One side of the seed crystal holder (9) facing the gas phase source (8) is provided with a seed crystal growth cavity (901), the inner wall of the seed crystal growth cavity (901) is provided with a connecting groove (902), and the outer part of the adjusting disc (903) is provided with a limiting protrusion (904) matched with the connecting groove (902).
6. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 5, characterized in that: The inside of the limiting protrusion (904) is provided with a deformation cavity (905), the adjusting disc (903) is in the shape of a ring, and the edge of the inner wall of the adjusting disc (903) in contact with the seed crystal growth cavity (901) is provided with a sealing corner (907).
7. The growth furnace for growing silicon carbide single crystal by PVT method according to claim 6, characterized in that: The bottom of the adjusting disc (903) is provided with two force applying grooves (906).