A rotating silicon carbide crystal growth furnace induction heating system and crystal growth furnace

Abstract

The present invention discloses an induction heating system and a crystal growth furnace for a rotating silicon carbide crystal growth furnace, and relates to the technical field of silicon carbide processing. It comprises a furnace body for processing silicon carbide; a heating component installed inside the furnace body for heating silicon carbide raw materials; a trigger component installed on the top of the furnace body for triggering the heating component to operate at different powers during operation; the trigger component comprises: a lifting component installed at one end of the top of the furnace body. The present invention allows the conductive pin to rotate in the limit tube in the heating component when the lifting component in the trigger component is in operation, so that electric energy triggers different sections in the heating resistor, thereby realizing precise heating of the silicon carbide raw materials, which not only improves the heating efficiency, but also can more evenly distribute the temperature field in the furnace by precisely controlling the working sections of the heating resistor, thereby ensuring the temperature stability during the crystal growth process.

Description

Technical Field

[0001] The invention relates to the technical field of silicon carbide processing, in particular to an induction heating system of a rotary silicon carbide crystal growth furnace and a crystal growth furnace. Background Art

[0002] In the field of silicon carbide processing, the crystal growth furnace is the key equipment to achieve high-quality silicon carbide crystal growth. Since the crystal growth furnace usually adopts resistance heating, but this method has problems such as uneven heating, high energy consumption, and slow response speed, in order to overcome these shortcomings, a rotating silicon carbide crystal growth furnace induction heating system and crystal growth furnace are urgently needed.

[0003] After searching, the Chinese invention patent with publication number "CN116770438A" discloses "a rotating silicon carbide crystal growth furnace induction heating system and crystal growth furnace". The application adopts the main shaft in the rotating structure to drive the crucible structure to rotate. When the main shaft rotates, four driven gears drive four L-shaped frames to rotate around the main shaft, so that the horizontal shaft can rotate around the main shaft. At the same time, the horizontal shaft can rotate on its own because of the meshing relationship between the bevel gear ring and the bevel gear. In this way, the first balls at the ends of the multiple stabilizing rods will support the spherical shaft on the main shaft, ensuring the stable rotation of the main shaft and the crucible structure, making the temperature field distribution easier to control during heating, ensuring the temperature uniformity, and ensuring the production quality of the crystal;

[0004] In addition, the Chinese invention patent with publication number "CN114411264A" discloses "a rotating silicon carbide crystal growth furnace induction heating system and crystal growth furnace". The application adjusts the magnetic field of the induction coil by periodic reciprocating rotation of the induction coil, thereby adjusting the distribution of the temperature field. The induction heating equipment replaces the rotation of the crucible with the rotation of the induction coil, avoiding the problem of unstable factors such as vibration in the crystal growth process caused by the rotation of the crucible that affect the growth of the crystal. The problems of complex structure and low stability caused by the rotation of the crucible are optimized.

[0005] However, in actual operation, the above-mentioned patent and similar patents do not have a separate mechanism for controlling the temperature field in the furnace, so that the temperature in the furnace cannot be directly controlled during actual processing, which reduces the stability of the crystal growth process. Summary of the invention

[0006] The object of the present invention is to provide an induction heating system for a rotary silicon carbide crystal growth furnace and a crystal growth furnace to solve the problems raised in the above background technology.

[0007] First aspect. To achieve the above-mentioned purpose, the present invention provides the following technical solution: an induction heating system for a rotating silicon carbide crystal growth furnace, comprising:

[0008] A furnace body for processing silicon carbide;

[0009] A heating assembly, installed inside the furnace body, for heating the silicon carbide raw material;

[0010] A trigger component is installed on the top of the furnace body and is used to trigger the heating component to operate at different powers during operation;

[0011] The trigger component comprises:

[0012] A lifting component is installed at one end of the top of the furnace body. A hole is opened at the center of the top of the furnace body, and a sealing sleeve is installed outside the hole of the furnace body;

[0013] The lifting component is externally connected to a power source, and a conductive rod passing through a sealing sleeve is installed at the lifting end of the lifting component, the bottom of the conductive rod is rotatably connected to a conductive cylinder, and a conductive pin is fixed to the outside of the conductive cylinder;

[0014] The heating assembly comprises:

[0015] Two carrying rings are fixed on the inner wall of the furnace body, and a spiral heating resistor is installed between the two carrying rings. A plurality of staggered conductive arms are fixed at equal angles inside the heating resistor. A limiting tube is fixed together with the plurality of conductive arms. A guide slideway matched with the conductive pin is provided inside the limiting tube. The conductive pin contacts the conductive arm with the help of the guide slideway and triggers the heating resistors of different lengths to work.

[0016] As a further preferred embodiment of the present technical solution, the lifting component, the conductive rod, the conductive cylinder, the conductive pin, the limit tube, the conductive arm and the heating resistor are electrically connected in sequence;

[0017] A reinforcement cover is fixed to the bottom of the limiting tube, the outer wall of the reinforcement cover is fixed on the inner wall of the furnace body, and the center position of the reinforcement cover is open for sleeve-mounted outside the limiting tube. Several notches are provided around the top of the reinforcement cover for allowing silicon carbide raw materials to enter the bottom of the furnace body.

[0018] As a further preferred embodiment of the present technical solution, the lifting component includes:

[0019] A transmission frame, the bottom of which is fixed to one end of the top of the furnace body, a screw is rotatably connected inside the transmission frame, a rotating motor is installed on the top of the transmission frame, and a driving shaft of the rotating motor passes through the transmission frame and is fixed to one end of the screw; a moving block is screwed outside the screw, and sliding channels are respectively opened on both sides of the transmission frame;

[0020] Limit pins are fixed at both ends of the outside of the moving block, and the limit pins are adapted to the sliding channel. One end of the two limit pins passes through the sliding channel and is fixed with stabilizing arms respectively. A reinforcement rod is fixed to one side of the outside of the moving block, and one end of the reinforcement rod and one end of the stabilizing arm are jointly fixed with a power-on frame, which is the moving end, and the bottom of the power-on frame is fixed to the end of the conductive rod away from the conductive cylinder.

[0021] As a further preferred embodiment of the present technical solution, power supply pins are fixed to the two ends of the transmission frame away from the screw rod, and rotating sleeves are installed at the bottom ends of the two sides of the outside of the transmission frame, and a rotating spring is fixedly installed between the rotating sleeve and the transmission frame;

[0022] A conductive wire harness is sleeved inside the rotating sleeve, one end of which is mounted on one end of the power supply frame, and the power supply pin, transmission frame, rotating sleeve, conductive wire harness and power supply frame are electrically connected in sequence.

[0023] In the second aspect, in order to improve the above technical solution, the present invention proposes a rotary silicon carbide crystal growth furnace, which uses the above rotary silicon carbide crystal growth furnace induction heating system, including:

[0024] A material taking cabinet is installed at the bottom of the furnace body, a discharge funnel is fixed at the bottom end of the furnace body, a discharge valve pipe is fixed at the bottom of the discharge funnel, and the discharge valve pipe is arranged inside the material taking cabinet after passing through the furnace body and the top of the material taking cabinet;

[0025] A telescopic rod is fixed at the bottom of the conductive cylinder, and a sealing plug matched with the discharge valve pipe is fixed at the bottom of the telescopic rod. The sealing plug is separated from the discharge valve pipe when the lifting component moves to the highest point.

[0026] As a further preferred embodiment of the present technical solution, a filling funnel and a monitoring meter are respectively installed on both sides of the top of the furnace body away from the position of the lifting component, and a pressure relief valve pipe for pressure relief gas is fixed on the top of one side of the outside of the furnace body;

[0027] A support frame is installed at a position of the material taking cabinet away from the cabinet door, and an electric air supply box is installed on the top of the support frame. The electric air supply box is connected to the furnace body.

[0028] As a further preferred embodiment of the present technical solution, a reinforcement seat is fixed to the bottom of the material collection cabinet, a power distribution cabinet is provided at one end outside the material collection cabinet, a control panel is installed on the top of one side outside the power distribution cabinet, and the control panel, power distribution cabinet, electric air supply box and rotating motor are electrically connected in sequence.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The rotary silicon carbide crystal growth furnace induction heating system and the crystal growth furnace enable the conductive pin to rotate in the limit tube in the heating component when the lifting component in the trigger component is in operation, so that the electric energy triggers different sections in the heating resistor, thereby realizing accurate heating of the silicon carbide raw material, which not only improves the heating efficiency, but also can more evenly distribute the temperature field in the furnace by accurately controlling the working sections of the heating resistor, thereby ensuring the temperature stability during the crystal growth process;

[0031] It should also be added that by synchronizing the electric energy to the inside of the lifting component and transmitting it to the inside of the heating component through the conductive pin, the entire system structure is made more compact, reducing the heat loss and electromagnetic interference that may be generated by the external line connection, and further improving the stability and reliability of the system;

[0032] In addition, in actual applications, since the design of the heating components and trigger components takes modularity into consideration, the corresponding components can be quickly replaced when maintenance or upgrades are required without having to dismantle the entire system on a large scale. At the same time, through the setting of monitoring tables and control panels, operators can monitor key parameters such as furnace temperature and pressure in real time to ensure the safety and controllability of the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is an isometric view of the present invention;

[0034] Figure 2 It is a left and right isometric view of the present invention;

[0035] Figure 3 is a main cross-sectional view of the present invention;

[0036] Figure 4 It is a structural composition diagram of the furnace body of the present invention;

[0037] Figure 5 It is a structural diagram of the trigger component of the present invention;

[0038] Figure 6 It is a structural composition diagram of the heating component of the present invention.

[0039] In the figure: 1, power distribution cabinet; 2, material cabinet; 3, reinforcement seat; 4, furnace body; 5, monitoring meter; 6, filling funnel; 7, pressure relief valve pipe; 8, trigger assembly; 801, sealing plug; 802, telescopic rod; 803, conductive cylinder; 804, conductive pin; 805, rotating sleeve; 806, conductive rod; 807, power pin; 808, transmission frame; 809, stabilizing arm; 810, sliding channel; 811 , rotating motor; 812, moving block; 813, power-on frame; 9, sealing sleeve; 10, control panel; 11, electric air supply box; 12, supporting frame; 13, discharge valve pipe; 14, discharge funnel; 15, heating assembly; 1501, guide slide; 1502, supporting ring; 1503, limit tube; 1504, heating resistor; 1505, notch; 1506, reinforcement cover; 1507, conductive arm. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0041] The rotating silicon carbide crystal growth furnace is a device for producing high-quality silicon carbide crystals. The key lies in the precise control of the heating process to ensure the stability of crystal growth. It should be added that in this application, the rotating feature is mainly reflected in the conductive cylinder 803.

[0042] As a preferred embodiment, Figure 1-Figure 6 The present invention provides a technical solution: an induction heating system for a rotating silicon carbide crystal growth furnace, comprising: a furnace body 4 for processing silicon carbide, a heating component 15 installed inside the furnace body 4 for heating the silicon carbide raw material, and a trigger component 8 installed on the top of the furnace body 4 for triggering the heating component 15 to operate at different powers during operation.

[0043] It should be noted that, in this embodiment, the trigger assembly 8 includes: a lifting component installed at one end of the top of the furnace body 4, a hole is opened at the center of the top of the furnace body 4, a sealing sleeve 9 is installed outside the hole of the furnace body 4, the lifting component is externally connected to the power supply, and a conductive rod 806 passing through the sealing sleeve 9 is installed at the lifting end of the lifting component, the bottom of the conductive rod 806 is rotatably connected to a conductive cylinder 803, and a conductive pin 804 is fixed to the outside of the conductive cylinder 803.

[0044] It should be added that, in the present embodiment, the heating assembly 15 includes: two supporting rings 1502, the two supporting rings 1502 are fitted and fixed on the inner wall of the furnace body 4, and a spiral heating resistor 1504 is installed between the two supporting rings 1502, and a plurality of staggered conductive arms 1507 are fixed at equal angles inside the heating resistor 1504, and a limiting tube 1503 is fixed together by the plurality of conductive arms 1507, and a guide slide 1501 adapted to the conductive pin 804 is provided inside the limiting tube 1503, and the conductive pin 804 contacts the conductive arm 1507 with the help of the guide slide 1501, and triggers the heating resistors 1504 of different lengths to work.

[0045] It should be emphasized that, when this embodiment is used specifically, a rotating mechanism can be installed at the bottom of the furnace body 4, and the rotating mechanism includes a rotating motor and a connecting frame. The rotating motor is connected to the bottom end of the surface of the furnace body 4 through the connecting frame. In this way, it can further ensure that the silicon carbide crystal is subjected to a uniform thermal field during the growth process, thereby improving the quality and growth rate of the crystal.

[0046] As a preferred embodiment, in this embodiment, the lifting component, the conductive rod 806, the conductive cylinder 803, the conductive pin 804, the limiting tube 1503, the conductive arm 1507 and the heating resistor 1504 are electrically connected in sequence. It should be noted that in this embodiment, a reinforcement cover 1506 is fixed to the bottom of the limiting tube 1503, and the outer wall of the reinforcement cover 1506 is fitted and fixed on the inner wall of the furnace body 4, and the center position of the reinforcement cover 1506 is an open design, which is used to be put on the outside of the limiting tube 1503, and a number of notches 1505 are opened around the top of the reinforcement cover 1506, and the notches 1505 are used to allow the silicon carbide raw material to enter the bottom of the furnace body 4.

[0047] As a preferred embodiment, in this embodiment, the lifting component includes: a transmission frame 808, the bottom of the transmission frame 808 is fixed to one end of the top of the furnace body 4, the transmission frame 808 is rotatably connected inside, a rotating motor 811 is installed on the top of the transmission frame 808, and the driving shaft of the rotating motor 811 passes through the transmission frame 808 and is fixed to one end of the screw; a moving block 812 is screwed outside the screw, and sliding channels 810 are respectively opened on both sides of the transmission frame 808, and limiting pins are respectively fixed at the two ends of the outside of the moving block 812, and the limiting pins and the sliding channels 810 are adapted to each other, and one end of the two limiting pins passes through the sliding channels 810 and is respectively fixed with stabilizing arms 809, and a reinforcement rod is fixed to one side of the outside of the moving block 812, and one end of the reinforcement rod and one end of the stabilizing arm 809 are jointly fixed with a power-on frame 813, and the power-on frame 813 is a moving end, and the bottom of the power-on frame 813 is fixed to the end of the conductive rod 806 away from the conductive cylinder 803.

[0048] It should be noted that, in this embodiment, the surface of the conductive cylinder 803 is coated with an insulating material to ensure that no short circuit occurs between the conductive cylinder 803 and the furnace body 4 in a high temperature environment.

[0049] As a preferred embodiment, in this embodiment, power supply pins 807 are fixed at both ends of the transmission frame 808 away from the screw rod, and rotating sleeves 805 are installed at the bottom ends of the two sides of the outside of the transmission frame 808, and a rotating spring is fixedly installed between the rotating sleeve 805 and the transmission frame 808 (shown in the attached figure). It should be supplemented that a conductive wire harness is sleeved inside the rotating sleeve 805, and one end of the conductive wire harness is installed at one end of the power supply frame 813. The power supply pin 807, the transmission frame 808, the rotating sleeve 805, the conductive wire harness and the power supply frame 813 are electrically connected in sequence.

[0050] It should be noted that, in this embodiment, the power-on rack 813 is connected to the power supply through a conductive wire harness to ensure that the entire transmission system can obtain a stable current supply. The design of the power-on rack 813 takes into account mechanical strength and conductivity. Its material is selected as a highly conductive metal, such as copper or aluminum, and is specially treated to improve corrosion resistance and wear resistance. In addition, in order to ensure the stable operation of the transmission system, the material of the transmission frame 808 is selected as high-strength alloy steel, which has good mechanical properties and anti-fatigue characteristics. The shape of the transmission frame 808 is designed to be a rectangular frame structure to ensure that it has sufficient rigidity and strength when subjected to torque.

[0051] As a preferred embodiment, refer to Figure 1-Figure 6 It can also be known that the present embodiment discloses a rotating silicon carbide crystal growth furnace. It should be noted that the rotating silicon carbide crystal growth furnace disclosed in the present embodiment uses a rotating silicon carbide crystal growth furnace induction heating system disclosed in the above embodiment, and includes: a material collection cabinet 2, which is installed at the bottom of the furnace body 4, and a discharge funnel 14 is fixed to the bottom end of the furnace body 4, and a discharge valve tube 13 is fixed to the bottom of the discharge funnel 14. After passing through the furnace body 4 and the top of the material collection cabinet 2, the discharge valve tube 13 is arranged inside the material collection cabinet 2, and a telescopic rod 802 is fixed to the bottom of the conductive cylinder 803, and a sealing plug 801 adapted to the discharge valve tube 13 is fixed to the bottom of the telescopic rod 802. The sealing plug 801 is separated from the discharge valve tube 13 when the lifting component runs to the highest point.

[0052] It should be added that, in the present embodiment, a filling funnel 6 and a monitoring meter 5 are respectively installed on both sides of the top of the furnace body 4 away from the position of the lifting component, a pressure relief valve pipe 7 for pressure relief gas is fixed on the top of one side of the outside of the furnace body 4, a support frame 12 is installed at a position away from the cabinet door of the material cabinet 2, and an electric air supply box 11 is installed on the top of the support frame 12, and the electric air supply box 11 and the furnace body 4 are connected. In addition, it should be noted that, in the present embodiment, a reinforcement seat 3 is fixed to the bottom of the material cabinet 2, a distribution cabinet 1 is provided at one end of the outside of the material cabinet 2, and a control panel 10 is installed on the top of one side of the outside of the distribution cabinet 1, and the control panel 10, the distribution cabinet 1, the electric air supply box 11 and the rotating motor 811 are electrically connected in sequence.

[0053] Finally, it should be emphasized that in the present embodiment, the monitoring meter 5 is an electronic detection meter, which is used to monitor the temperature, pressure, concentration and other data in the furnace in real time to ensure the stability of the environment during the growth of silicon carbide crystals. The monitoring meter 5 is connected to the control unit through a wire. The control unit automatically adjusts the power output of the heating component 15 according to the data provided by the monitoring meter 5 to maintain the temperature in the furnace within a set range. In addition, the electric gas supply box 11 is used to transport protective gas into the furnace body 4 to ensure the purity of the environment during the growth of silicon carbide crystals. The electric gas supply box 11 is connected to the gas inlet inside the furnace body 4 through a pipeline, and the control unit also controls the gas flow and pressure of the electric gas supply box 11 to meet the demand for protective gas at different growth stages.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rotary silicon carbide crystal growth furnace induction heating system, characterized in that: include: A furnace body (4) for processing silicon carbide; A heating assembly (15) is installed inside the furnace body (4) and is used to heat the silicon carbide raw material; A trigger component (8) is installed on the top of the furnace body (4) and is used to trigger the heating component (15) to operate at different powers during operation; The trigger component (8) comprises: A lifting component is installed at one end of the top of the furnace body (4); a hole is opened at the center of the top of the furnace body (4); and a sealing sleeve (9) is installed outside the hole of the furnace body (4); The lifting component is connected to an external power source, and a conductive rod (806) passing through a sealing sleeve (9) is installed at the lifting end of the lifting component, the bottom of the conductive rod (806) is rotatably connected to a conductive cylinder (803), and a conductive pin (804) is fixed to the outside of the conductive cylinder (803); The heating component (15) comprises: Two supporting rings (1502) are fixedly attached to the inner wall of the furnace body (4), and a spiral heating resistor (1504) is installed between the two supporting rings (1502). A plurality of staggered conductive arms (1507) are fixed at equal angles inside the heating resistor (1504). The plurality of conductive arms (1507) are jointly fixed with a limiting tube (1503). A guide slideway (1501) adapted to the conductive pin (804) is provided inside the limiting tube (1503). The conductive pin (804) contacts the conductive arm (1507) with the help of the guide slideway (1501) and triggers the heating resistors (1504) of different lengths to work.

2. The induction heating system for a rotating silicon carbide crystal growth furnace according to claim 1, characterized in that: The lifting component, the conductive rod (806), the conductive cylinder (803), the conductive pin (804), the position limiting tube (1503), the conductive arm (1507) and the heating resistor (1504) are electrically connected in sequence; A reinforcement cover (1506) is fixed to the bottom of the limiting tube (1503), the outer wall of the reinforcement cover (1506) is fixed to the inner wall of the furnace body (4), and the center position of the reinforcement cover (1506) is open for sleeve-mounted outside the limiting tube (1503), and a plurality of notches (1505) are provided around the top of the reinforcement cover (1506), and the notches (1505) are used to allow the silicon carbide raw material to enter the bottom of the furnace body (4).

3. The induction heating system for a rotating silicon carbide crystal growth furnace according to claim 1, characterized in that: The lifting component comprises: A transmission frame (808), wherein the bottom of the transmission frame (808) is fixed to one end of the top of the furnace body (4), a screw is rotatably connected inside the transmission frame (808), a rotating motor (811) is installed on the top of the transmission frame (808), and a driving shaft of the rotating motor (811) passes through the transmission frame (808) and is fixed to one end of the screw; a moving block (812) is screwed outside the screw, and sliding channels (810) are respectively opened on both sides of the transmission frame (808); Limit pins are fixed at both ends of the outside of the moving block (812), the limit pins are adapted to the sliding channel (810), one end of the two limit pins passes through the sliding channel (810) and is fixed with a stabilizing arm (809), a reinforcing rod is fixed to one side of the outside of the moving block (812), one end of the reinforcing rod and one end of the stabilizing arm (809) are jointly fixed with a power-on frame (813), the power-on frame (813) is the moving end, and the bottom of the power-on frame (813) is fixed to one end of the conductive rod (806) away from the conductive cylinder (803).

4. The induction heating system for a rotating silicon carbide crystal growth furnace according to claim 3, characterized in that: Power supply pins (807) are fixed to the two ends of the transmission frame (808) away from the screw rod, and rotating sleeves (805) are installed at the bottom ends of the two sides of the outside of the transmission frame (808), and a rotating spring is fixedly installed between the rotating sleeve (805) and the transmission frame (808); A conductive wire bundle is sleeved inside the rotating sleeve (805), one end of which is mounted on one end of the power supply frame (813), and the power supply pin (807), the transmission frame (808), the rotating sleeve (805), the conductive wire bundle and the power supply frame (813) are electrically connected in sequence.

5. A rotary silicon carbide crystal growth furnace, using the rotary silicon carbide crystal growth furnace induction heating system according to any one of claims 1 to 4, characterized in that: include: A material taking cabinet (2) is installed at the bottom of the furnace body (4); a discharge funnel (14) is fixed at the bottom end of the furnace body (4); a discharge valve pipe (13) is fixed at the bottom of the discharge funnel (14); the discharge valve pipe (13) is arranged inside the material taking cabinet (2) after passing through the furnace body (4) and the top of the material taking cabinet (2); A telescopic rod (802) is fixed at the bottom of the conductive cylinder (803), and a sealing plug (801) adapted to the discharge valve tube (13) is fixed at the bottom of the telescopic rod (802). The sealing plug (801) is separated from the discharge valve tube (13) when the lifting component moves to the highest point.

6. The rotary silicon carbide crystal growth furnace according to claim 5, characterized in that: A filling funnel (6) and a monitoring meter (5) are respectively installed on both sides of the top of the furnace body (4) away from the lifting component, and a pressure relief valve pipe (7) for relieving pressure gas is fixed on the top of one side outside the furnace body (4); A support frame (12) is installed at a position of the material taking cabinet (2) away from the cabinet door, and an electric air supply box (11) is installed on the top of the support frame (12). The electric air supply box (11) and the furnace body (4) are connected.

7. The rotary silicon carbide crystal growth furnace according to claim 6, characterized in that: A reinforcement seat (3) is fixed at the bottom of the material taking cabinet (2), a power distribution cabinet (1) is arranged at one end outside the material taking cabinet (2), a control panel (10) is installed at the top of one side outside the power distribution cabinet (1), and the control panel (10), the power distribution cabinet (1), the electric air supply box (11) and the rotating motor (811) are electrically connected in sequence.

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