Kyropoulos method crystal growth device

Abstract

The utility model belongs to the technical field of crystal preparation, and discloses a Kyropoulos method crystal growth device which comprises a hearth, and a heating area is arranged in the hearth; the bearing seat and the crucible are arranged in the heating area; the seed rod extends into the crucible; at least two groups of annular heating assemblies are arranged on the inner wall of the heating area, the at least two groups of heating assemblies are mutually independent and adjacently arranged in the vertical direction, and each group of heating assemblies is provided with a temperature control thermocouple; when the number of the heating assemblies is two, the two heating assemblies are the upper heating assembly and the lower heating assembly respectively, and the crucible is located in the area surrounded by the lower heating assembly. When the number of the heating assemblies is three, the three heating assemblies are the upper heating assembly, the middle heating assembly and the lower heating assembly respectively, and the crucible is located in the area surrounded by the middle heating assembly. The kyropoulos method crystal growing device can avoid polycrystals and internal defects, and can grow crystals with larger sizes.

Description

Technical Field

[0001] The utility model relates to the technical field of crystal preparation, in particular to a Kyropoulos crystal growth device. Background Technique

[0002] Bismuth germanate (BGO) crystal is a scintillation detection material with excellent comprehensive performance, having advantages such as high density, excellent e / γ energy resolution, high refractive index, and no hygroscopicity, and is widely used in various fields, such as high-energy physics, nuclear physics, nuclear medicine, security inspection, environmental monitoring, food detection, oil logging, and so on.

[0003] The raw materials for preparing bismuth germanate crystal are bismuth trioxide and germanium dioxide, which are prepared by mixing bismuth trioxide and germanium dioxide and heating them to a temperature above the melting point for reaction. Currently, the main preparation methods for bismuth germanate crystal are two kinds, one is the Bridgman method, and the other is the Czochralski method. The devices used in the two preparation methods have differences in structure.

[0004] For example, the device adopting the Bridgman method has a publication number of CN102828230B and an application name of a growth device and method for growing wide-plate bismuth germanate crystal by the Bridgman method. By controlling the vertical descent of the alumina pulling crucible and the temperature gradient of the crystal growth interface, the crystal grows. However, the furnace shell size of the Bridgman method growth device is limited, and it is difficult to prepare large-size crystals. During the crystal growth process, direct observation is not possible, and the growth cycle is relatively long.

[0005] For example, the device adopting the Czochralski method has a publication number of JP2001261485A and an application name of a device and method for manufacturing single crystal. After the target diameter is reached but before the target length is reached during crystal growth, the melt is pulled by a pulling mechanism at a constant pulling speed and rotation speed to make the crystal grow; however, the Czochralski method requires controlling a slow pulling rate and a fast rotation rate, which is very disadvantageous for growing large-size crystals for industrial applications.

[0006] The main difference between the Kyropoulos method and the Czochralski method is that during the isodiametric stage, the crystal can be continuously crystallized without pulling the seed crystal upward. It is generally used for sapphire crystal growth and is more suitable for growing large-size crystals. However, the temperature field structure design of the existing Kyropoulos method crystal device is not reasonable enough, not suitable for the growth of multi-component crystals, and situations such as polycrystallization and internal defects are likely to occur. Content of the Utility Model

[0007] The purpose of the utility model is to provide a Kyropoulos crystal growth device with a more reasonable temperature field structure design, suitable for the growth of multi-component crystals, effectively preventing polycrystallization and internal defects, applicable to the growth of multi-component crystals, and capable of growing higher-quality and larger-size multi-component crystals.

[0008] To achieve this purpose, the utility model adopts the following technical solutions:

[0009] The Kyropoulos method crystal growth device includes:

[0010] A furnace chamber, the furnace chamber includes a furnace body and a furnace cover, the furnace cover seals the top opening of the furnace body, and a heating zone surrounded by heat insulation materials is provided inside the furnace body;

[0011] A carrier seat and a crucible, both are arranged in the heating zone, and the crucible is placed above the carrier seat;

[0012] A seed crystal rod, which can be lifted and lowered in the vertical direction and can be inserted into the heating zone to extend into the crucible, and the seed crystal rod is used for crystal seeding;

[0013] At least two groups of annular heating components are arranged on the inner wall of the heating zone, at least two groups of the heating components are independent of each other and are arranged adjacent to each other in the vertical direction, and each group of the heating components is equipped with a temperature control thermocouple;

[0014] When the heating components are set to two groups, the two groups of heating components are respectively an upper heating component and a lower heating component, the crucible is located in the area surrounded by the lower heating component, and the lowest point of the crucible is higher than the lowest point of the lower heating component;

[0015] When the heating components are set to three groups, the three groups of heating components are respectively an upper heating component, a middle heating component and a lower heating component, and the crucible is located in the area surrounded by the middle heating component.

[0016] As an optional technical solution, when the heating components are set to two groups, the height difference between the lowest point of the crucible and the lowest point of the lower heating component is more than 8 cm, and the height difference between the highest point of the crucible and the highest point of the upper heating component is more than 8 cm.

[0017] As an optional technical solution, when the heating components are set to three groups, the height difference between the highest point of the crucible and the highest point of the upper heating component is more than 8 cm but less than 12 cm, and the height difference between the lowest point of the crucible and the highest point of the lower heating component is more than 8 cm but less than 12 cm.

[0018] As an optional technical solution, the gap between two adjacent groups of the heating components does not exceed 1 cm.

[0019] As an optional technical solution, the following are provided inside the furnace body:

[0020] A heat insulation bottom plate;

[0021] A heat insulation surrounding plate, surrounding the outer periphery of the heating component;

[0022] A heat insulation cover plate, covering the top of the heat insulation surrounding plate;

[0023] The heat-insulating bottom plate, the heat-insulating side plate and the heat-insulating cover plate enclose the heating area, the carrier seat, the crucible and the heating assembly are all located in the heating area, and a through hole for the seed crystal rod to pass through is provided in the middle of the heat-insulating cover plate.

[0024] As an alternative technical solution, the heat-insulating side plate is of a double-layer structure.

[0025] As an alternative technical solution, the furnace cover is provided with an observation port, and the heat-insulating cover plate is provided with a first observation hole. Through the observation port and the first observation hole, the melting state of the raw material in the crucible can be observed.

[0026] As an alternative technical solution, the top opening of the crucible is further covered with a crucible cover, and the crucible cover is provided with a second observation hole. The midpoints of the observation port, the first observation hole and the second observation hole are located on the same straight line.

[0027] As an alternative technical solution, the observation port is made of glass.

[0028] As an alternative technical solution, a cooling channel is provided inside the wall of the furnace chamber, and the cooling channel is used to introduce a cooling medium to reduce the temperature of the furnace chamber.

[0029] The beneficial effects of the present utility model:

[0030] The Kyropoulos crystal growth device provided by the present utility model includes a furnace chamber, a carrier seat, a crucible, a heating assembly and a seed crystal rod. The furnace chamber includes a furnace body and a furnace cover. The furnace cover seals the top opening of the furnace body, and a heating area surrounded by heat-insulating materials is provided inside the furnace body; the carrier seat and the crucible are both arranged in the heating area, and the crucible is placed above the carrier seat; the seed crystal rod can be lifted and lowered in the vertical direction and can be inserted into the heating area to extend into the crucible, and the seed crystal rod is used for crystal seeding; at least two groups of annular heating assemblies are arranged on the inner wall of the heating area, and at least two groups of heating assemblies are independent of each other and are arranged adjacent to each other in the vertical direction. Each group of heating assemblies is configured with a temperature control thermocouple; when there are two groups of heating assemblies, the two groups of heating assemblies are respectively an upper heating assembly and a lower heating assembly, and the crucible is located in the area surrounded by the lower heating assembly; when there are three groups of heating assemblies, the three groups of heating assemblies are respectively an upper heating assembly, a middle heating assembly and a lower heating assembly, and the crucible is located in the area surrounded by the middle heating assembly.

[0031] The present utility model arranges at least two groups of annular heating assemblies in the heating area, and each group of heating assemblies is configured with a temperature control thermocouple, so that the heating assemblies can be heated separately to control the temperature of the area corresponding to the heating assembly.

[0032] When there are two sets of heating components, the two sets of heating components are the upper heating component and the lower heating component respectively. The crucible is located in the area surrounded by the lower heating component. The temperature of the area surrounded by the lower heating component is higher than that of the area surrounded by the upper heating component. The height difference between the lowest point of the crucible and the lowest point of the lower heating component is more than 8 cm, and the crucible is located in the area surrounded by the lower heating component. When there are three sets of heating components, the three sets of heating components are the upper heating component, the middle heating component and the lower heating component respectively. The temperature of the area surrounded by the three heating components increases gradually from top to bottom. The crucible is located in the area surrounded by the middle heating component. Through the above structural design, both the upper and lower parts of the crucible are protected by a stable temperature field, avoiding the interference of the external environment on the temperature field of the crucible, forming a stable temperature gradient in the crucible, reducing the occurrence of polycrystals or internal defects, and growing high-quality and large-sized crystals, especially crystals with a size of more than 5 inches. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 FIG. is a schematic structural diagram of the Kyropoulos crystal growth apparatus of the present invention when there are three sets of heating components;

[0034] Figure 2 is Figure 1 a partial enlarged view of position A in FIG.;

[0035] Figure 3 FIG. is a schematic structural diagram of the Kyropoulos crystal growth apparatus of the present invention when there are two sets of heating components;

[0036] Figure 4 is Figure 3 a partial enlarged view of position B in FIG.

[0037] In the figure:

[0038] 1. Furnace chamber; 11. Furnace body; 111. Cooling channel; 12. Furnace cover; 121. Observation port; 13a. Upper heating zone; 13b. Middle heating zone; 13c. Lower heating zone; 14. Heat preservation bottom plate; 15. Heat preservation enclosure panel; 16. Heat preservation cover plate; 161. First observation hole; 17. Air inlet; 18. Air outlet;

[0039] 2. Carrier seat;

[0040] 3. Crucible;

[0041] 4a. Upper heating component; 4b. Middle heating component; 4c. Lower heating component;

[0042] 5. Seed crystal rod;

[0043] 6. Temperature control thermocouple;

[0044] 7. Crucible cover; 71. Second observation hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present utility model, rather than limiting the present utility model. Additionally, it should be noted that for the sake of description, only the parts related to the present utility model rather than all the structures are shown in the drawings.

[0046] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0047] In the present utility model, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0048] In the description of this embodiment, the orientation or positional relationships such as "up", "down", "right", etc. are based on the orientation or positional relationships shown in the drawings. It is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0049] Embodiment

[0050] As Figures 1 to 4As shown in the figure, the Kyropoulos crystal growth apparatus provided in this embodiment includes a furnace chamber 1, a carrier 2, a crucible 3, at least two sets of annular heating components, a seed crystal rod 5, and a temperature control thermocouple 6. The furnace chamber 1 includes a furnace body 11 and a furnace lid 12. The furnace lid 12 seals the top opening of the furnace body 11. Inside the furnace body 11, there is a heating zone surrounded by heat insulation materials. The carrier 2 and the crucible 3 are both arranged in the heating zone. The crucible 3 is placed above the carrier 2. The seed crystal rod 5 can be lifted and lowered in the vertical direction and can be inserted into the heating zone to extend into the crucible 3. The seed crystal rod 5 is used for crystal seeding. The lifting control and rotation control mechanisms of the seed crystal rod 5 are prior arts, so no further description will be given here. At least two sets of annular heating components are arranged on the inner wall of the heating zone. The at least two sets of heating components are independent of each other and are arranged adjacent to each other in the vertical direction. Each set of heating components is equipped with a temperature control thermocouple 6.

[0051] As Figure 3 and Figure 4 shown, in one embodiment, the heating components are set to two sets, which are the upper heating component 4a and the lower heating component 4c respectively. The crucible 3 is located in the area surrounded by the lower heating component 4c; the height difference between the lowest point of the crucible 3 and the lowest point of the lower heating component 4c is more than 8 cm.

[0052] When the heating components are set to two sets, the area surrounded by the lower heating component 4c is the lower heating zone 13c, and the area surrounded by the upper heating component 4a is the upper heating zone 13a. The crucible 3 is located in the lower heating zone 13c.

[0053] As Figure 1 and Figure 2 shown, in another embodiment, the heating components are set to three sets, which are the upper heating component 4a, the middle heating component 4b, and the lower heating component 4c respectively. The crucible 3 is located in the area surrounded by the middle heating component 4b.

[0054] When the heating components are set to three sets, the area surrounded by the lower heating component 4c is the lower heating zone 13c, the area surrounded by the middle heating component 4b is the middle heating zone 13b, and the area surrounded by the upper heating component 4a is the upper heating zone 13a. The crucible 3 is located in the middle heating zone 13b.

[0055] Optionally, the furnace chamber 1 is provided with an air inlet 17 and an air outlet 18. Gas is input into the interior of the furnace chamber 1 from the air inlet 17 and discharged from the air outlet 18.

[0056] Optionally, the material of the crucible 3 is platinum.

[0057] Optionally, the heating component is a nickel-cadmium-aluminum heating element.

[0058] Optionally, the material of the carrier 2 is alumina.

[0059] When there are two sets of heating components, the height difference between the highest point of the crucible 3 and the highest point of the upper heating component 4a is more than 8 cm, and the height difference between the lowest point of the crucible 3 and the lowest point of the lower heating component 4c is more than 8 cm. The highest point of the crucible 3 is at least 8 cm lower than the highest point of the upper heating component 4a, and the lowest point of the crucible 3 is at least 8 cm higher than the lowest point of the lower heating component 4c. The areas above and below the crucible 3 can both be heated to the preset temperature, preventing temperature mutations in the areas above and below the crucible 3. For example, if the area above the crucible 3 rapidly drops from a higher temperature to a lower temperature due to uncontrollable temperature, the heat in the area where the crucible 3 is located accelerates and diffuses to the area above the crucible 3, and the temperature in the area where the crucible 3 is located rapidly decreases, which will affect the crystallization quality of the raw materials in the crucible 3.

[0060] Optionally, when there are three sets of heating components, the height difference between the highest point of the crucible 3 and the highest point of the upper heating component 4a is more than 8 cm but less than 12 cm, and the height difference between the lowest point of the crucible 3 and the highest point of the lower heating component 4c is more than 8 cm but less than 12 cm. The areas above and below the crucible 3 can both be heated to the preset temperature, preventing temperature mutations in the areas above and below the crucible 3.

[0061] Optionally, when there are three sets of heating components, the gap between adjacent two sets of heating components does not exceed 1 cm, so as to form a better temperature gradient in the heating zone. The crucible 3 is completely located in the area surrounded by the middle heating component 4b, and the gap between adjacent two sets of heating components is misaligned with the crucible 3, reducing the influence of this gap on the crystallization of the melt in the crucible 3.

[0062] Optionally, when there are two sets of heating components, the gap between adjacent two sets of heating components does not exceed 1 cm. The crucible 3 is completely located in the area surrounded by the lower heating component 4c, and the gap between the upper heating component 4a and the lower heating component 4c is misaligned with the crucible 3, reducing the influence of this gap on the crystallization of the melt in the crucible 3.

[0063] Optionally, a heat-insulating bottom plate 14, a heat-insulating enclosing plate 15 and a heat-insulating cover plate 16 are provided inside the furnace body 11. The heat-insulating enclosing plate 15 surrounds the outer periphery of the heating component; the heat-insulating cover plate 16 is covered on the top of the heat-insulating enclosing plate 15; the heat-insulating bottom plate 14, the heat-insulating enclosing plate 15 and the heat-insulating cover plate 16 enclose a heating zone, and the bearing seat 2, the crucible 3 and the heating component are all located in the heating zone. A through hole for the seed crystal rod 5 to pass through is provided in the middle of the heat-insulating cover plate 16.

[0064] In this embodiment, the thermal insulation enclosure 15 is provided with a double-layer structure. The height of the inner thermal insulation board is lower than that of the outer thermal insulation board. A stepped structure is formed between the top of the outer thermal insulation board and the top of the inner thermal insulation board. The thermal insulation cover plate 16 is embedded in the stepped structure. The bottom surface of the thermal insulation cover plate 16 is closely attached to the top surface of the inner thermal insulation board, and the side surface of the thermal insulation cover plate 16 is closely attached to the inner side surface of the outer thermal insulation board.

[0065] Optionally, the materials of the thermal insulation bottom plate 14, the thermal insulation enclosure 15, and the thermal insulation cover plate 16 are mullite or alumina.

[0066] Optionally, an oxygen channel is provided inside the furnace chamber 1, and the oxygen channel communicates with the heating zone.

[0067] Optionally, the furnace cover 12 is provided with an observation port 121, and the thermal insulation cover plate 16 is provided with a first observation hole 161. Through the observation port 121 and the first observation hole 161, the melting state of the raw material in the crucible 3 can be observed, which is convenient for the operator to control the crystallization of the raw material in a timely manner. The first observation hole 161 is provided with a light-transmitting and heat-insulating member such as glass. Through the glass, the inside of the furnace chamber 1 can be observed, and the glass can prevent the rapid escape of heat.

[0068] Optionally, the top opening of the crucible 3 is further covered with a crucible cover 7, and the crucible cover 7 is provided with a second observation hole 71. The midpoints of the observation port 121, the first observation hole 161, and the second observation hole 71 are located on the same straight line. The second observation hole 71 is provided with a light-transmitting and heat-insulating member such as glass. Through the glass, the inside of the furnace chamber 1 can be observed, and the glass can prevent the rapid escape of heat.

[0069] Optionally, the observation port 121 is made of glass. Through the glass, the inside of the furnace chamber 1 can be observed, and the glass can prevent the rapid escape of heat.

[0070] Optionally, a cooling channel 111 is provided inside the wall body of the furnace chamber 1. The cooling channel 111 is used to introduce a cooling medium to reduce the temperature of the furnace chamber 1 and prevent scalding the operator or burning other equipment.

[0071] Optionally, the material of the furnace chamber 1 is stainless steel.

[0072] Experimental Example 1

[0073] Use Figure 3 And 4 The Bridgman method crystal growth device of the embodiment is used to prepare bismuth germanate crystals. Bismuth trioxide and germanium dioxide are put into the crucible 3 according to a mass ratio of 2:3. After evacuating the crucible 3, oxygen is continuously introduced, the volatiles are shielded from diffusion, and crystal growth is started, including the following steps:

[0074] Heating: Control the heating zone to heat up. Stop heating up after the raw materials melt into a melt. The melting temperature of the raw materials is 1050°C. Therefore, in this step, the middle temperature zone 13b should be heated up to 5 - 10°C higher than 1050°C. At this time, the seed crystal rod rotates at a speed of 3 - 5 rpm.

[0075] Seeding: Control the seed crystal rod 5 to descend. After the seed crystal touches the liquid surface of the melt, lift the seed crystal rod 5 upward. The lifting speed of the seed crystal rod 5 is controlled at 3 - 5 mm / h, and the rotation speed is 3 - 5 rpm until the diameter of the grown crystal reaches 8 cm.

[0076] Shoulder formation: Reduce the lifting speed of the seed crystal rod 5 to 0.1 - 1 mm / h, and the rotation speed is 3 - 5 rpm to expand the diameter of the crystal to 140 cm.

[0077] Shoulder turning: Increase the lifting speed of the seed crystal rod 5 to 3 - 5 mm / h, and the rotation speed is 3 - 5 rpm until the diameter of the crystal growth stabilizes at 140 cm.

[0078] Constant diameter growth: Stop lifting the seed crystal rod 5 upward, but the rotation speed remains at 3 - 5 rpm. Control the upper heating zone 13a and the lower heating zone 13c to cool down at a speed of 0.1 - 2°C / h to make the melt crystallize downward until the crystal reaches the preset weight.

[0079] Tail shrinking: Continue to lift the seed crystal rod 5 upward, increase the lifting speed to 3 - 5 mm / h, and the rotation speed is 5 - 8 rpm to shrink the diameter of the crystal tail into a point.

[0080] Cooling: Control the heating zone to cool down evenly until room temperature, and then take out the crystal.

[0081] In steps S2 - S7, the radial temperature gradient in the heating zone is 0.5 - 1 K / cm, and the axial temperature gradient is 0.1 - 1.5 K / cm.

[0082] The diameter of the crystal grown in this experimental example is 140 mm, without cracking, colorless and transparent, and there is no light path when irradiated with a helium-neon laser pen.

[0083] Experimental Example 2

[0084] The difference from Experimental Example 1 is that the crucible 3 moves upward, a part of the crucible 3 is located in the upper heating zone 13a, and a part of the crucible 3 is located in the lower heating zone 13c. The diameter of the crystal grown in this experimental example is 140 mm, but there are bubbles inside the grown size, and there is an obvious light path under the irradiation of a helium-neon laser pen.

[0085] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present utility model. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present utility model shall be included within the protection scope of the claims of the present utility model.

Claims

1. The Kyropoulos method crystal growth apparatus, characterized in that Comprising: A furnace chamber (1), the furnace chamber (1) includes a furnace body (11) and a furnace cover (12), the furnace cover (12) seals the top opening of the furnace body (11), and an inner part of the furnace body (11) is provided with a heating zone surrounded by heat-insulating materials; A carrier seat (2) and a crucible (3), both are arranged in the heating zone, and the crucible (3) is placed above the carrier seat (2); A seed crystal rod (5), which can be lifted and lowered in the vertical direction and can be inserted into the heating zone to extend into the crucible (3), and the seed crystal rod (5) is used for crystal seeding; At least two sets of annular heating components are arranged on the inner wall of the heating zone, at least two sets of the heating components are independent of each other and are arranged adjacent to each other in the vertical direction, and each set of the heating components is configured with a temperature control thermocouple (6); When the heating components are two sets, the two sets of heating components are respectively an upper heating component (4a) and a lower heating component (4c), the crucible (3) is located in the area surrounded by the lower heating component (4c), and the lowest point of the crucible (3) is higher than the lowest point of the lower heating component (4c); When the heating components are three sets, the three sets of heating components are respectively an upper heating component (4a), a middle heating component (4b) and a lower heating component (4c), and the crucible (3) is located in the area surrounded by the middle heating component (4b).

2. The Kyropoulos method crystal growth apparatus according to claim 1, wherein When the heating components are two sets, the height difference between the lowest point of the crucible (3) and the lowest point of the lower heating component (4c) is more than 8 cm, and the height difference between the highest point of the crucible (3) and the highest point of the upper heating component (4a) is more than 8 cm.

3. The Kyropoulos method crystal growth apparatus according to claim 1, wherein, When the heating components are three sets, the height difference between the highest point of the crucible (3) and the highest point of the upper heating component (4a) is more than 8 cm but less than 12 cm, and the height difference between the lowest point of the crucible (3) and the highest point of the lower heating component (4c) is more than 8 cm but less than 12 cm.

4. The Kyropoulos method crystal growth apparatus according to claim 1, wherein, The gap between two adjacent sets of the heating components does not exceed 1 cm.

5. The Kyropoulos crystal growth apparatus according to any one of claims 1-4, characterized in that, The inner part of the furnace body (11) is provided with: A heat-insulating bottom plate (14); A heat-insulating surrounding plate (15), surrounding the outer periphery of the heating components; A heat-insulating cover plate (16), covering the top of the heat-insulating surrounding plate (15); The heat-insulating bottom plate (14), the heat-insulating surrounding plate (15) and the heat-insulating cover plate (16) enclose the heating zone, the carrier seat (2), the crucible (3) and the heating components are all located in the heating zone, and a through hole for the seed crystal rod (5) to pass through is provided in the middle of the heat-insulating cover plate (16).

6. The Kyropoulos crystal growth apparatus according to claim 5, wherein, The heat-insulating surrounding plate (15) is of a double-layer structure.

7. The Kyropoulos method crystal growth device according to claim 6, characterized in that, The furnace cover (12) is provided with an observation port (121), and the heat-insulating cover plate (16) is provided with a first observation hole (161), and the melting state of the raw material in the crucible (3) can be observed through the observation port (121) and the first observation hole (161).

8. The Kyropoulos method crystal growth apparatus according to claim 7, wherein The top opening of the crucible (3) is also covered with a crucible lid (7), and the crucible lid (7) is provided with a second observation hole (71), and the midpoints of the observation port (121), the first observation hole (161), and the second observation hole (71) are located on the same straight line.

9. The Kyropoulos method crystal growth apparatus according to claim 7, characterized in that, The observation port (121) is made of glass.

10. The Kyropoulos method crystal growth apparatus according to any one of claims 1-4, characterized in that, A cooling channel (111) is provided inside the wall of the furnace chamber (1), and the cooling channel (111) is used to introduce a cooling medium to reduce the temperature of the furnace chamber (1).

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