Magnetic control type silicon carbide crystal growth equipment
By setting an anode, cathode and magnet disk in the silicon carbide crystal retracting equipment, an electric field and a magnetic field are formed, the silicon carbide crystal retracting efficiency is improved, crystal defects are reduced, and good lattice arrangement and internal stress reduction are achieved.
Patent Information
- Application Number
- CN202421944822.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-13
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-08-13
AI Technical Summary
In the traditional silicon carbide crystal growth process, silicon carbide molecules are in a molecular extreme disturbance state under high temperature environments, resulting in low crystal growth efficiency, large internal stress and many crystal defects.
Magnetically controlled silicon carbide crystal growth equipment is used to set an anode and a cathode in the graphite crucible to ionize the gas, and use a magnet disk to increase the degree of gas ionization to promote the growth of silicon carbide seed crystals.
It improves the crystal growth efficiency, maintains the good lattice arrangement of silicon carbide seeds, reduces the internal stress and defects of the crystal, and even forms superlattice crystals.
Smart Images
Figure CN222948513U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of crystal growth equipment, and in particular to a magnetron silicon carbide crystal growth equipment. Background Art
[0002] In the traditional growth process of silicon carbide seed crystals, a method of heating silicon carbide powder in a crystal growth furnace is generally used for crystal growth. Specifically, the crystal growth furnace is heated, and the silicon carbide powder is sublimated into a gas in the sublimation zone of the crystal growth furnace. At this time, the silicon carbide molecules are in a state of molecular extreme disturbance under a high temperature environment, and reach the crystal growth zone in the crystal growth furnace to form silicon carbide seed crystals. However, it takes a long time for the silicon carbide molecules in a disturbed state to reach the crystal growth zone, and the crystal growth efficiency is low. In addition, during the process of nucleation and formation of silicon carbide seed crystals in the crystal growth zone, severe internal stress will be generated, resulting in lattice dislocation and crystal defects. Utility Model Content
[0003] The purpose of the utility model is to provide a magnetron silicon carbide crystal growth device, which can not only improve the crystal growth efficiency, but also enable the silicon carbide seed crystal to maintain a good lattice arrangement, significantly reduce the internal stress of the crystal, and reduce crystal defects.
[0004] The embodiment of the utility model is achieved as follows:
[0005] The utility model provides a magnetron type silicon carbide crystal growth device, which comprises a graphite crucible, a heater, an anode, a cathode and a magnet disk;
[0006] The bottom of the graphite crucible is used to place silicon carbide powder, a heater is arranged on the periphery of the graphite crucible, the heater is used to heat and gasify the silicon carbide powder, and the top of the graphite crucible is used to grow silicon carbide seed crystals;
[0007] The anode is arranged below the graphite crucible, and the cathode is arranged above the graphite crucible. An electric field is formed between the anode and the cathode to ionize the gas in the graphite crucible and flow to the top of the graphite crucible. The magnet disk is arranged above the cathode and is used to increase the degree of ionization of the gas in the graphite crucible.
[0008] In an optional embodiment, the magnet disk includes a support disk and magnets, the support disk is provided with a plurality of receiving holes, and the magnets are disposed in the receiving holes.
[0009] In an optional embodiment, the magnets are arranged in a ring-like shape with intervals, and magnets of the same polarity are arranged in the same ring, and magnets of different polarities are arranged in two adjacent rings, and all the rings are concentrically arranged.
[0010] In an optional embodiment, the gas filled in the graphite crucible includes argon.
[0011] The beneficial effects of the magnetron silicon carbide crystal growth device provided by the embodiment of the utility model include:
[0012] 1. An anode is set at the bottom of the graphite crucible, and a cathode is set at the top of the graphite crucible. After the anode and the cathode are pressurized, an electric field is formed to ionize the gas in the graphite crucible. A large amount of process gas filled in the graphite crucible will form a large number of positive ions (such as Ar + ), a large number of positive ions will move toward the direction of the cathode, that is, move vertically upward, which will push the gas or ions involved in crystal growth upward, thereby improving the crystal growth efficiency;
[0013] 2. After the anode and cathode are pressurized, the gas generated by the silicon carbide powder in the graphite crucible is ionized into gas-phase plasma, and then the gas-phase plasma grows silicon carbide seed crystals in the crystal growth area, which can maintain a good lattice arrangement of the silicon carbide seed crystals, significantly reduce the internal stress of the crystal, and reduce crystal defects;
[0014] 3. After the large amount of process gas filled in the graphite crucible is ionized, a large amount of electrons (e - ), under the action of the magnetic field formed by the magnet disk, the movement trajectory of electrons in the plasma will be extended, the probability of electrons participating in the collision and ionization process of gas molecules will be increased, the degree of ionization will be increased, the degree of silicon carbide ions will be high, and the internal stress of the crystal will be further reduced, reducing crystal defects, and even forming superlattice crystals. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 A schematic diagram of the structure of a magnetron silicon carbide crystal growth device provided in an embodiment of the utility model;
[0017] Figure 2 for Figure 1 Schematic diagram of the structure of the magnet disk.
[0018] Icons: 1-graphite crucible; 2-heater; 3-anode; 4-cathode; 5-support plate; 6-magnet; 7-silicon carbide powder; 8-powder sublimation zone; 9-positive ions; 10-silicon carbide seed crystal; 11-magnetic field; 12-magnet disk. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.
[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0022] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0023] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0025] Please refer to Figure 1 This embodiment provides a magnetron silicon carbide crystal growth device, which includes a graphite crucible 1, a heater 2, an anode 3, a cathode 4 and a magnet disk 12.
[0026] The bottom of the graphite crucible 1 is used to place silicon carbide powder 7, and the heater 2 is arranged on the periphery of the graphite crucible 1. The heater 2 is used to heat and vaporize the silicon carbide powder 7. The area where the surface layer of the silicon carbide powder 7 is located is the powder sublimation zone 8, and the top of the graphite crucible 1 is used to grow silicon carbide seed crystals 10.
[0027] The anode 3 is arranged below the graphite crucible 1, and the cathode 4 is arranged above the graphite crucible 1. An electric field is formed between the anode 3 and the cathode 4 to ionize the gas in the graphite crucible 1 and flow toward the top of the graphite crucible 1. The magnet disk 12 is arranged above the cathode 4. The partial magnetic field 11 formed by the magnet disk 12 is as shown in FIG. Figure 1 As shown by the middle dotted line, the magnet disk 12 is used to increase the degree of gas ionization in the graphite crucible 1 .
[0028] For details, please refer to Figure 2 The magnet disk 12 includes a support disk 5 and magnets 6. The support disk 5 is provided with a plurality of receiving holes, and the magnets 6 are arranged in the receiving holes. The magnets 6 are arranged in annular intervals, and magnets 6 of the same polarity are arranged on the same ring, and magnets 6 of different polarities are arranged on two adjacent rings, and all the rings are arranged concentrically.
[0029] In this embodiment, an S-polarity magnet 6 is disposed at the center of the support plate 5, and a circle of N-polarity magnets 6 and S-polarity magnets 6 are sequentially disposed around the S-polarity magnet 6 in the center. In other embodiments, the arrangement of the magnets 6 can be flexibly set according to the required distribution form and strength of the magnetic field 11.
[0030] Of course, the magnetron silicon carbide crystal growth equipment provided in this embodiment also has conventional parts of existing crystal growth equipment, such as a vacuum chamber for accommodating parts such as a graphite crucible 1, a heater 2, a cathode 4, an anode 3, a magnet disk 12, and a gas supply system and a vacuum pumping system connected to the vacuum chamber.
[0031] The working process of the magnetron silicon carbide crystal growth equipment provided in this embodiment is as follows:
[0032] First, the heater 2 heats the silicon carbide powder 7 in the graphite crucible 1. The heated silicon carbide powder 7 generates gas (mainly the silicon carbide powder 7 in the powder sublimation zone 8 generates gas first). The main reactions are as follows:
[0033] SiC(s)=Si(g)+C(s)
[0034] 2SiC(s)=Si(g)+SiC2 (g)
[0035] 2SiC(s)=C(s)+Si 2 C(g)
[0036] The s in the brackets indicates that the substance is in a solid state, and the g in the brackets indicates that the substance is in a gaseous state.
[0037] Then, the anode 3 and the cathode 4 are pressurized (may be several thousand volts) to form an electric field to ionize the gas in the graphite crucible 1. A large amount of process gas (such as Ar) filled in the graphite crucible 1 is ionized to form a large number of positive ions 9 (such as Ar). + ) and electron (e - ), the reaction is as follows:
[0038] Ar=Ar + +e -
[0039] A large number of positive ions 9(Ar + ) will move toward the direction where the cathode 4 is located, that is, move vertically upward, which will push the gas or ions involved in the crystal growth to move upward together, thereby improving the crystal growth efficiency.
[0040] At the same time, the gas generated by the silicon carbide powder 7 will also be ionized into gas phase plasma, and then the silicon carbide seed crystal 10 will be grown in the crystal growth area by the gas phase plasma, so that the silicon carbide seed crystal 10 can maintain a good lattice arrangement, significantly reduce the internal stress of the crystal, and reduce crystal defects.
[0041] Under the action of the magnetic field 11 formed by the magnet disk 12, a large number of electrons (e - )The trajectory of electron movement in the plasma will be extended, because the direction of the Lorentz force exerted on the electron at every moment is always perpendicular to its current direction of movement, which increases the probability of electrons participating in the collision and ionization process of gas molecules, increases the degree of ionization, and increases the degree of silicon carbide ions, further reducing the internal stress of the crystal, reducing crystal defects, and even forming superlattice crystals.
[0042] The beneficial effects of the magnetron silicon carbide crystal growth device provided by the embodiment of the utility model include:
[0043] 1. An anode 3 is arranged below the graphite crucible 1, and a cathode 4 is arranged above the graphite crucible 1. After the anode 3 and the cathode 4 are pressurized, an electric field is formed to ionize the gas in the graphite crucible 1. A large amount of process gas filled in the graphite crucible 1 is ionized to form a large amount of positive ions 9 (such as Ar + ), a large number of positive ions 9 will move toward the direction where the cathode 4 is located, that is, move vertically upward, which will push the gas or ions involved in the crystal growth to move upward together, thereby improving the crystal growth efficiency;
[0044] 2. After the anode 3 and the cathode 4 are pressurized, the gas generated by the silicon carbide powder 7 in the graphite crucible 1 is ionized into gas-phase plasma, and then the silicon carbide seed crystal 10 is grown in the crystal growth area by the gas-phase plasma, so that the silicon carbide seed crystal 10 can maintain a good lattice arrangement, significantly reduce the internal stress of the crystal, and reduce crystal defects;
[0045] 3. After the large amount of process gas filled into the graphite crucible 1 is ionized, a large amount of electrons (e - ), under the action of the magnetic field 11 formed by the magnet disk 12, the movement trajectory of electrons in the plasma will be extended, the probability of electrons participating in the collision and ionization process of gas molecules will be increased, the degree of ionization will be increased, the degree of silicon carbide ions will be high, and the internal stress of the crystal will be further reduced, the crystal defects will be reduced, and even superlattice crystals can be formed.
[0046] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A magnetron silicon carbide crystal growth device, characterized in that: The magnetron silicon carbide crystal growth device comprises a graphite crucible (1), a heater (2), an anode (3), a cathode (4) and a magnet disk (12); The bottom of the graphite crucible (1) is used to place silicon carbide powder (7), the heater (2) is arranged on the periphery of the graphite crucible (1), the heater (2) is used to heat and gasify the silicon carbide powder (7), and the top of the graphite crucible (1) is used to grow silicon carbide seed crystals (10); The anode (3) is arranged below the graphite crucible (1), and the cathode (4) is arranged above the graphite crucible (1). An electric field is formed between the anode (3) and the cathode (4) to ionize the gas in the graphite crucible (1) and flow toward the top of the graphite crucible (1). The magnet disk (12) is arranged above the cathode (4). The magnet disk (12) is used to increase the degree of ionization of the gas in the graphite crucible (1).
2. The magnetron silicon carbide crystal growth equipment according to claim 1, characterized in that: The magnet disk (12) comprises a support disk (5) and a magnet (6); a plurality of accommodating holes are provided on the support disk (5), and the magnet (6) is arranged in the accommodating holes.
3. The magnetron silicon carbide crystal growth equipment according to claim 2, characterized in that: The magnets (6) are arranged in annular shapes at intervals, and the magnets (6) of the same polarity are arranged in the same ring, and the magnets (6) of different polarities are arranged in two adjacent rings, and all the rings are arranged concentrically.
4. The magnetron silicon carbide crystal growth equipment according to claim 1, characterized in that: The gas filled in the graphite crucible (1) includes argon gas.