Bridgman crystal growing furnace and crystal growing method

Abstract

The invention relates to the technical field of crystal growth, and discloses a Bridgman crystal growing furnace and a crystal growing method.The Bridgman crystal growing furnace comprises a heating furnace and a heat preservation stabilizing device; the heating furnace is internally provided with a crystallization cavity, the crystallization cavity is a cylindrical cavity, the heat preservation and stabilization device is arranged at one end in the crystallization cavity, the heat preservation and stabilization device is in a round tube shape, the heat preservation and stabilization device and the crystallization cavity are coaxially arranged, and the heat preservation and stabilization device is used for allowing a crystallization container to penetrate through and limiting the crystallization container. Due to the cooperation of the heat preservation and stabilization device and the crystallization cavity, the heat preservation and stabilization device mechanically supports and limits the crystallization container in the crystallization growth process of the crystallization container, so that the crystallization container is always located at the central position of the crystallization cavity, and the phenomenon that the crystallization container is bent or deviated under the working conditions of high-temperature heat flow, mechanical vibration and the like is effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of crystal growth technology, and in particular to a Bridgeman crystal growth furnace and a crystal growth method. Background Technology

[0002] The Bridgman crystal growth method is a technique that achieves directional solidification and growth of crystals by controlling the temperature gradient between the melt and the solid phase. The Bridgman method is widely used in the preparation of single crystals for semiconductor materials, optical crystals, and metal alloys. The Bridgman growth method generally requires a growth furnace. The raw material is placed in a quartz tube, and then the quartz tube containing the raw material is placed inside the growth furnace, where the raw material can grow and crystallize. In the process of developing this invention, the inventors discovered at least the following problems: During crystal growth, poor insulation of the growth furnace leads to significant heat loss, affecting the uniformity of the growth temperature and wasting energy. Furthermore, the lack of fixation for the quartz tube causes it to easily shift or deform during crystal growth, resulting in asymmetrical heating on both sides of the quartz tube, affecting the consistency, stability, and quality of crystal growth. Summary of the Invention

[0003] The present invention aims to provide a Bridgman crystal growth furnace and a crystal growth method to solve the technical problem of poor crystal growth quality in the prior art in Bridgman crystal growth furnaces.

[0004] The technical solutions adopted by the embodiments of the present invention to solve their technical problems are as follows: A Bridgman crystal growth furnace is provided, including a heating furnace and a heat preservation and stabilization device; The heating furnace is provided with a crystallization chamber, which is a cylindrical cavity. The heat preservation and stabilization device is located at one end of the crystallization chamber. The heat preservation and stabilization device is cylindrical and is coaxially arranged with the crystallization chamber. The heat preservation and stabilization device is used to allow the crystallization container to pass through and to limit the crystallization container.

[0005] Optionally, the heat preservation and stabilization device includes a circular tube body, which is coaxially arranged with the crystallization cavity. The circular tube body is provided with a limiting cavity and a vacuum cavity. The limiting cavity is a cylindrical cavity and is coaxially arranged with the crystallization cavity. The limiting cavity is used to allow the crystallization container to pass through and to limit the crystallization container. The vacuum cavity is arranged around the limiting cavity.

[0006] Optionally, the vacuum cavity is filled with a heat-insulating medium, which includes at least one of quartz, ceramic, and porous materials.

[0007] Optionally, the main body of the circular tube is a transparent circular tube.

[0008] Optionally, the distance between the outer wall of the circular tube body and the inner wall of the crystallization cavity is D1, where 0 < D1 ≤ 2 mm; The limiting cavity is a cylindrical cavity, the crystallization container includes a quartz tube, and the distance between the inner wall of the limiting cavity and the outer wall of the quartz tube is D2, where 0 < D2 ≤ 1 mm; The ratio of the height of the main body of the circular tube to its outer diameter is R1, and the ratio of the height of the main body of the circular tube to the length of the quartz tube is R2, wherein 1≤R1 and R2≤1 / 2.

[0009] Optionally, the heating furnace includes a furnace body and a heating device, the heating device being disposed on the furnace body, the furnace body including a high-temperature zone and a low-temperature zone, the high-temperature zone being located in the upper part of the furnace body, and the low-temperature zone being located in the lower part of the furnace body.

[0010] Optionally, the Bridgeman crystal growth furnace further includes a heat insulation plug, the crystallization cavity is a cylindrical through hole, the heat insulation plug is detachably disposed at the bottom of the crystallization cavity, the heat preservation and stabilization device is located at the upper part of the crystallization cavity and at the upper part of the crystallization container, and the lower part of the crystallization container is located between the heat preservation and stabilization device and the heat insulation plug.

[0011] Optionally, the Bridgeman crystal growth furnace further includes a settling machine and a settling line, and the heat preservation and stabilization device further includes a fixing part, which is located on the upper part of the circular tube body. The settling machine is located above the heating furnace, one end of the settling line is connected to the settling machine, and the other end of the settling line is connected to the fixing part and the crystallization container.

[0012] Optionally, the fixing part is a ring, the upper end of the crystallization container is provided with a circular hole, and the other end of the settling line passes through the ring and the circular hole in sequence so that the other end of the settling line is connected to the fixing part and the crystallization container.

[0013] Embodiments of the present invention also provide a crystal growth method using the Bridgman crystal growth furnace described above, comprising: Select the corresponding mass of crystallizing raw materials according to the atomic ratio of the desired product molecular formula, mix the crystallizing raw materials evenly, grind them, and place them in the lower part of the crystallization container; The crystallization container containing the crystallization raw material and the heat preservation and stabilization device are placed in the high-temperature zone of the crystallization chamber, wherein the crystallization container passes through the heat preservation and stabilization device, the heat preservation and stabilization device is located above the crystallization container, the lower part of the crystallization container is located below the heat preservation and stabilization device, and the lowest point of the heat preservation and stabilization device is higher than the lowest point of the high-temperature zone. The heating furnace is heated to raise the temperature so that the high-temperature zone reaches a first target temperature and the low-temperature zone reaches a second target temperature; The crystallization container is maintained in the high-temperature zone for a preset time so that the crystallization raw material in the lower part of the crystallization container reaches a molten state; The crystallization container moves from the high-temperature zone to the low-temperature zone at a preset speed. The molten raw material gradually crystallizes after reaching the low-temperature zone. The high-temperature zone is located above the low-temperature zone. Once the raw material in the crystallization container has crystallized, heating of the furnace is stopped, and the furnace is gradually cooled to room temperature.

[0014] Compared with existing technologies, in the Bridgman crystal growth furnace and crystal growth method of the present invention, the crystallization cavity is cylindrical, and the heat preservation and stabilization device is tubular, with the heat preservation and stabilization device and the crystallization cavity coaxially arranged. During crystal growth, the crystallization container passes through the heat preservation and stabilization device. Due to the cooperation between the heat preservation and stabilization device and the crystallization cavity, the heat preservation and stabilization device provides mechanical support and restraint to the crystallization container during crystallization growth, ensuring that the crystallization container remains centered within the crystallization cavity. This effectively prevents the crystallization container from bending or shifting under conditions such as high-temperature heat flow and mechanical vibration. When the crystallization container is a tubular structure such as a quartz tube, it also ensures symmetrical heating on both sides of the crystallization container, resulting in consistent crystal orientation and good centering. Furthermore, since the heat preservation and stabilization device is located at one end of the crystallization cavity, it can seal one end of the crystallization cavity during crystal growth. The heat preservation and stabilization device has a heat preservation and insulation function, reducing heat loss from the heating furnace during crystal growth, saving energy, improving energy efficiency, and preventing uneven crystallization temperature, thus improving the uniformity of crystal growth temperature. In summary, the Bridgeman crystal growth furnace of the present invention, by incorporating a heat preservation and stabilization device, not only supports and limits the crystallization container, ensuring it remains centered within the crystallization chamber during growth, but also provides heat insulation, thus guaranteeing the stability and uniformity of crystal growth. Furthermore, the heating furnace and heat preservation and stabilization device in the Bridgeman crystal growth furnace of the present invention are modular in structure, facilitating easy disassembly, assembly, maintenance, and replacement.

[0015] The crystal growth method of the present invention also has the above-mentioned advantages, which will not be repeated here. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram of the Bridgman crystal growth furnace in one embodiment of the present invention; Figure 2 This is a schematic diagram of the thermal insulation and stabilization device in one embodiment of the present invention; Figure 3 This is a cross-sectional view of a heat preservation and stabilization device according to an embodiment of the present invention.

[0018] Figure label: 100. Bridgeman crystal growth furnace; 10. Heating furnace; 12. Crystallization chamber; 20. Heat preservation and stabilization device; 22. Circular tube body; 222. Vacuum chamber; 24. Fixing part; 30. Crystallization container; 32. Circular hole; 40. Heat insulation plug; 50. Settling machine; 60. Settling line. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly on the other element, or one or more intermediate elements may exist between them. The terms "upper," "lower," "left," "right," "upper end," "lower end," "top," and "bottom," etc., used in this specification indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are used only for the convenience of describing the present invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0021] Please refer to Figure 1 One embodiment of the present invention provides a Bridgeman crystal growth furnace 100, including a heating furnace 10 and a heat preservation and stabilization device 20; the heating furnace 10 is provided with a crystallization cavity 12, which is a cylindrical cavity, and the heat preservation and stabilization device 20 is disposed at one end of the crystallization cavity 12. The heat preservation and stabilization device 20 is cylindrical and is coaxially arranged with the crystallization cavity 12. The heat preservation and stabilization device 20 is used to allow the crystallization container 30 to pass through and to limit the crystallization container 30.

[0022] In this embodiment of the Bridgman crystal growth furnace 100, a heating device, which can be an induction coil, surrounds the furnace 10. The induction coil heats the furnace 10, creating a heating zone inside, with a maximum temperature of 1200°C. When the crystallization container 30 is located in the crystallization chamber 12, it contains raw materials for crystallization, allowing the raw materials to grow into single crystals. These raw materials include perovskite source materials such as cesium bromide, lead bromide, cesium iodide, lead iodide, cesium chloride, and lead chloride. The crystallization container 30 can be a quartz tube, preferably a vacuum quartz tube. It is understood that the crystallization container 30 can also be a crucible, etc. The furnace 10 includes a high-temperature zone and a low-temperature zone. The high-temperature zone is located at the upper part of the furnace 10, and the low-temperature zone is located at the lower part. When the crystallization container 30 is located in the crystallization chamber 12, the high-temperature zone keeps the raw materials in a molten state, while the low-temperature zone allows the raw materials to grow into single crystals.

[0023] In the Bridgeman crystal growth furnace 100 of this embodiment, the crystallization cavity 12 is cylindrical, and the heat preservation and stabilization device 20 is tubular, with the two devices coaxially arranged. During crystal growth, the crystallization container 30 passes through the heat preservation and stabilization device 20. Due to the cooperation between the heat preservation and stabilization device 20 and the crystallization cavity 12, the heat preservation and stabilization device 20 provides mechanical support and restraint to the crystallization container 30 during the crystallization growth process, ensuring that the crystallization container 30 remains centered within the crystallization cavity 12. This effectively prevents the crystallization container 30 from bending or shifting under conditions such as high-temperature heat flow and mechanical vibration. When the crystallization container 30 is a tubular structure such as a quartz tube, it also ensures symmetrical heating on both sides, resulting in consistent crystal orientation and good centering. Furthermore, since the heat preservation and stabilization device 20 is located at one end of the crystallization cavity 12, it can seal one end of the crystallization cavity 12 during crystal growth. The heat preservation and stabilization device 20 has a heat preservation and insulation function, reducing heat loss from the heating furnace 10 during crystal growth, saving energy, improving energy efficiency, and preventing uneven crystallization temperature, thus improving the uniformity of crystal growth temperature. In summary, in the Bridgman crystal growth furnace 100 of this embodiment, by setting the heat preservation and stabilization device 20, the crystallization container 30 can be supported and limited, ensuring that the crystallization container 30 is in the center of the crystallization cavity 12 during crystal growth. It also has a heat preservation and insulation effect, thus ensuring the stability and uniformity of crystal growth. In the Bridgman crystal growth furnace 100 of this embodiment, the heating furnace 10 is usually made of high-temperature resistant materials, such as quartz or ceramics, to withstand high-temperature environments. The heating furnace 10 and the heat preservation and stabilization device 20 are modular structures, thus facilitating disassembly, assembly, maintenance, and replacement.

[0024] Please refer to the above as well. Figures 1 to 3In one embodiment, the heat preservation and stabilization device 20 includes a circular tube body 22, which is coaxially arranged with the crystallization cavity 12. The circular tube body 22 contains a limiting cavity 222 and a vacuum cavity 224. The limiting cavity 222 is a cylindrical cavity, coaxially arranged with the crystallization cavity 12. The limiting cavity 222 allows the crystallization container 30 to pass through and limits its position. The vacuum cavity 224 surrounds the limiting cavity 222. Specifically, the vacuum cavity 224 is provided within the tube wall of the circular tube body 22. The diameter of the limiting cavity 222 is smaller than the diameter of the vacuum cavity 224. The limiting cavity 222 accommodates and limits the crystallization container 30. Through the cooperation of the circular tube body 22 and the cylindrical crystallization cavity 12, the crystallization container 30 is confined to the center position of the crystallization cavity 12 during crystal growth. Because the tube body 22 has a vacuum cavity 224 in its wall, the tube body 22 has a good thermal insulation effect, which can prevent heat loss from the crystallization cavity 12. It is understood that in some other embodiments, other structural forms can also be used as the thermal insulation structure of the tube body 22, such as ceramic structures, ceramic porous structures, etc., which will not be listed here.

[0025] The main body of the circular tube 22 can be made of quartz material.

[0026] In one embodiment, the vacuum cavity 224 is filled with a heat-insulating medium. By filling the vacuum cavity 224 with a heat-insulating medium, the heat insulation effect of the circular tube body 22 can be further improved.

[0027] Specifically, in one embodiment, the heat insulation medium includes at least one of quartz, ceramic, and porous materials. For example, quartz particles, ceramic sheets, porous materials, or a mixture of any two or more of quartz, ceramic, and porous materials can be filled into the vacuum chamber 224. By filling with the above-mentioned heat insulation medium, the heat insulation effect of the circular tube body 22 can be further improved.

[0028] In one embodiment, the method for manufacturing the circular tube body 22 includes: obtaining a top cover and a base, both of which can be made of quartz material. The base has a receiving groove and a first through hole, the receiving groove surrounding the first through hole, the first through hole being located at the center of the base, and the top cover having a second through hole at its center, the diameters of the first and second through holes being equal. Then, a heat-insulating medium such as quartz, ceramic, or porous material is placed into the receiving groove. The top cover is then placed on the base, aligning the first and second through holes. Finally, the top cover and base are fused together. After the top cover and base are fused and sealed, a vacuum cavity 224 is formed between the receiving groove and the top cover, and the first and second through holes merge to form a limiting cavity 222. Since the melting points of quartz, ceramic, and porous materials are not lower than the melting points of the top cover and base, the state of the heat-insulating medium is not affected during the fusion connection of the top cover and base.

[0029] To enable real-time monitoring of the crystallization process, in one embodiment, the main body 22 of the circular tube is a transparent circular tube. By using a transparent circular tube, the crystal growth state can be observed in real time, and remedial measures can be taken promptly if unexpected situations occur during the experiment. For example, the transparent circular tube allows for real-time observation of whether gas leakage occurs during the crystallization process; if gas leakage occurs, relevant remedial measures can be taken to avoid greater losses.

[0030] Before crystal growth, the circular tube body 22 and quartz tube need to be pre-placed into the crystallization cavity 12. If the distance between the outer wall of the circular tube body 22 and the crystallization cavity 12 is too large, it will affect the heat insulation effect. If the distance between the outer wall of the circular tube body 22 and the crystallization cavity 12 is too small, it may cause collisions during the placement of the circular tube body 22 into the crystallization cavity 12, resulting in damage to the circular tube body 22 and the inner wall of the crystallization cavity 12. Therefore, in one embodiment, the distance between the outer wall of the circular tube body 22 and the inner wall of the crystallization cavity 12 is less than or equal to 2 mm, and the distance between the outer wall of the circular tube body 22 and the inner wall of the crystallization cavity 12 is greater than zero. Preferably, the distance between the outer wall of the circular tube body 22 and the inner wall of the crystallization cavity 12 is 2 mm. This ensures that the circular tube body 22 can be smoothly slid and disassembled along the inner wall of the crystallization cavity 12, facilitating replacement and maintenance, while also ensuring the heat insulation effect of the circular tube body 22.

[0031] In one embodiment, the limiting cavity 222 is a cylindrical cavity, and the crystallization container 30 includes a quartz tube with a conical bottom end. Similarly, when the quartz tube is passed through the limiting cavity 222 of the cylindrical tube body 22, if the gap between the quartz tube and the inner wall of the limiting cavity 222 is too large, it will affect the limiting effect of the inner wall of the limiting cavity 222 on the quartz tube. If the gap between the quartz tube and the inner wall of the limiting cavity 222 is too small, it may cause collisions or other phenomena during the insertion of the quartz tube into the limiting cavity 222, resulting in damage to the cylindrical tube body 22 and the quartz tube. The distance between the inner wall of the limiting cavity 222 and the outer wall of the quartz tube is less than or equal to 1 mm, and the distance between the inner wall of the limiting cavity 222 and the outer wall of the quartz tube is greater than zero. Preferably, the distance between the inner wall of the limiting cavity 222 and the outer wall of the quartz tube is 1 mm. This ensures that the quartz tube is centered in the crystallization cavity 12 and avoids damage to the quartz tube and the main body 22 of the circular tube during installation. Furthermore, since the limiting cavity 222 is cylindrical and coaxially arranged with the crystallization cavity 12, the fit between the quartz tube and the inner wall of the limiting cavity 222 further facilitates ensuring that the quartz tube is centered in the crystallization cavity 12.

[0032] In one embodiment, the heating furnace 10 includes a furnace body and a heating device (not shown in the figure). The heating device is disposed on the furnace body, and a crystallization chamber 12 is provided inside the furnace body. The furnace body includes a high-temperature zone and a low-temperature zone. The high-temperature zone is located in the upper part of the furnace body, and the low-temperature zone is located in the lower part of the furnace body. The heat preservation and stabilization device 20 is located in the high-temperature zone. The temperature of the high-temperature zone is slightly higher than the melting point of the raw material to be crystallized, and the temperature of the low-temperature zone is slightly lower than the melting point of the raw material to be crystallized. The heating device is an induction coil, which is wrapped around the perimeter of the furnace body and close to the upper part of the furnace body, i.e., close to the high-temperature zone. The induction coil is connected to a power supply device, which is equipped with a PLC program control system for controlling the heating power of the induction coil.

[0033] The circular tube body 22 is circular in shape, and the ratio of its height to its outer diameter affects the limiting and heat insulation effects of the quartz tube. Generally, during crystal growth, the circular tube body 22 is located at the upper part of the crystallization cavity 12. The circular tube body 22 can limit the upper part of the quartz tube, reducing its radial sway. If the height of the circular tube body 22 is too low, it will affect the limiting and heat insulation effects on the quartz tube. In one embodiment, the ratio of the height to the outer diameter of the circular tube body 22 is R1, and the ratio of the height of the circular tube body 22 to the length of the quartz tube is R2, where 1≤R1 and R2≤1 / 2. This setting ensures that when 1≤R1, the projected area of ​​the circular tube body 22 on the quartz tube is large, and the circular tube body 22 can cover a large portion of the quartz tube, thus providing a better radial limiting effect on the quartz tube. Furthermore, since the height of the circular tube body 22 is relatively larger than its outer diameter, the circular tube body 22 has a better heat insulation effect when the heat inside the crystallization cavity 12 is conducted upward along its axis. In addition, when R2≤1 / 2, that is, when the height of the circular tube body 22 does not exceed 1 / 2 of the length of the quartz tube, this setting can avoid the circular tube body 22 covering the quartz tube too much, thereby avoiding affecting the crystal growth of the raw materials inside the quartz tube.

[0034] The crystallization cavity 12 can be a cylindrical through-hole or a cylindrical blind hole. When the crystallization cavity 12 is a cylindrical blind hole, the bottom of the crystallization cavity 12 is closed, and the cylindrical tube body 22 is located at the upper part of the crystallization cavity 12. During installation, the heating furnace 10 needs to be disassembled and moved, and then the cylindrical tube body 22 and the quartz tube are installed from above the heating furnace 10 into the crystallization cavity 12. To make the installation of the cylindrical tube body 22 and the quartz tube from the crystallization cavity 12 more convenient, and to ensure the heat insulation effect of the crystallization cavity 12, in one embodiment, the Bridgeman crystal growth furnace 100 also includes a heat insulation plug 40. The crystallization cavity 12 is a cylindrical through-hole, the heat insulation plug 40 is detachably disposed at the bottom of the crystallization cavity 12, the heat insulation stabilizing device 20 is located at the upper part of the crystallization cavity 12, and the heat insulation stabilizing device 20 is located at the upper part of the crystallization container 30, with the lower part of the crystallization container 30 located between the heat insulation stabilizing device 20 and the heat insulation plug 40. The heat insulation plug 40 can provide heat insulation for the bottom of the crystallization chamber 12. At the same time, after the heat insulation plug 40 is removed from the bottom of the crystallization chamber 12, the round tube body 22 and the quartz tube can also be installed into the crystallization chamber 12 from the bottom of the crystallization chamber 12 without moving or disassembling the heating furnace 10. Therefore, it is convenient to install and remove.

[0035] In this embodiment, the heat insulation plug 40 and the bottom of the crystallization cavity 12 can be interference-fitted, so that the heat insulation plug 40 can be directly inserted into the bottom of the crystallization cavity 12. It is understood that in some embodiments, the heat insulation plug 40 can be cylindrical, with external threads on the outer surface of the heat insulation plug 40 and internal threads on the bottom of the crystallization cavity 12. Through the cooperation of the external and internal threads, the heat insulation plug 40 and the bottom of the crystallization cavity 12 can be detachably connected, making disassembly and assembly convenient.

[0036] Among them, the heat insulation plug 40 can be a ceramic alumina plug.

[0037] In one embodiment, the Bridgeman crystal growth furnace 100 further includes a settling machine 50 and a settling line 60. The heat preservation and stabilization device 20 also includes a fixing part 24, which is located on the upper part of the circular tube body 22. The settling machine 50 is located above the heating furnace 10. One end of the settling line 60 is connected to the settling machine 50, and the other end of the settling line 60 is connected to the fixing part 24 and the crystallization container 30. The settling machine 50 can be a uniform speed settling machine, and the settling line 60 can be a high-temperature iron-chromium-aluminum wire. The settling machine 50 can pull one end of the settling line 60, and the settling machine 50 is located above the heating furnace 10. With this configuration, the settling machine 50 can pull the settling line 60, which in turn pulls the fixing part 24 and the crystallization container 30, allowing it to be installed from below the crystallization chamber 12 into the crystallization chamber 12. The crystallization container 30 is a quartz tube. By setting the fixing part 24, the other end of the settlement line 60 can be connected to the upper part of the circular tube body 22, and the other end of the settlement line 60 passes through the upper part of the circular tube body 22 and the upper part of the quartz tube in sequence, so that the other end of the settlement line 60 connects the upper part of the circular tube body 22 and the upper part of the quartz tube in series.

[0038] During the crystallization process, the portion of the raw material in the high-temperature zone within the crystallization chamber 12 of the quartz tube melts after a period of time, while the portion in the low-temperature zone gradually crystallizes. During crystallization, the settling machine 50 gradually lowers the circular tube body 22 and the quartz tube via the settling line 60, allowing the molten raw material in the high-temperature zone to enter the low-temperature zone and gradually crystallize. This process yields high-quality single-crystal crystals and improves crystallization efficiency.

[0039] The fixing part 24 and the circular tube body 22 can be integrally formed. When the fixing part 24 and the circular tube body 22 are integrally formed, both the fixing part 24 and the circular tube body 22 can be made of quartz material. Alternatively, the fixing part 24 and the circular tube body 22 can be detachably connected or fixedly connected. The fixing part 24 is used to connect to the other end of the settling line 60. Specifically, the fixing part 24 is used to connect to the lower end of the settling line 60, and the upper end of the settling line 60 is used to connect to the settling machine 50. The fixing part 24 can be a variety of structures that can connect to the settling line 60. In order to reduce the manufacturing cost and installation efficiency of the fixing part 24, in one embodiment, the fixing part 24 is a ring, and the upper end of the crystallization container 30 is provided with a circular hole 32. The other end of the settling line 60 passes through the ring and the circular hole 32 in sequence so that the other end of the settling line 60 is connected to the fixing part 24 and the crystallization container 30. The crystallization container 30 is a quartz tube. When the fixing part 24 is a ring, the mold opening is more convenient when manufacturing the mold for the fixing part 24, thus reducing the manufacturing cost of the fixing part 24. In addition, the upper end of the quartz tube is provided with a circular hole 32, and the lower end of the settling line 60 can pass smoothly through the circular hole 32 and the ring. The lower end of the settling line 60 is connected to the circular tube body 22 through the ring, and the lower end of the settling line 60 is also connected to the upper end of the quartz tube through the circular hole 32, which makes disassembly and assembly convenient.

[0040] It is understood that the fixing part 24 can be a triangular frame structure or other shapes of fixing structure, which will not be listed here.

[0041] In one embodiment, in the manufacturing method of the circular tube body 22, a fixing part 24 is provided on the upper cover, and the upper cover and the fixing part 24 can be integrally formed.

[0042] In some embodiments, preferably, the ring is connected to the top end of the circular tube body 22. This arrangement facilitates the alignment of the ring and the circular hole 32 without interference. It is understood that in some embodiments, the ring may also be located at other positions on the circular tube body 22.

[0043] In some embodiments, preferably, there are two rings, located at opposite ends of the circular tube body 22, with the upper part of the quartz tube situated between the two rings, and the circular hole 32 also situated between the two rings. The other end of the settling line 60 passes sequentially through one of the rings, the circular hole 32, and the other ring. The other end of the settling line 60 is connected to the circular tube body 22 via the two rings, and also connects to the quartz tube via the circular hole 32, bringing the upper parts of the circular tube body 22 and the upper parts of the quartz tube close together and coaxially arranged. Therefore, it also serves to fix the circular tube body 22 and the quartz tube. Furthermore, the symmetrical arrangement of the two rings makes the forces on both sides of the circular tube body 22 and the quartz tube more balanced, further ensuring that the quartz tube is centered in the crystallization cavity 12 during crystallization.

[0044] In one embodiment, the crystallization method using the Bridgeman crystal growth furnace 100 provided in the above embodiments includes the following steps: S1. Select the corresponding mass of crystallizing raw materials according to the atomic ratio of the desired product molecular formula, mix the crystallizing raw materials evenly, grind them and place them in the lower part of the crystallization container 30; in a specific embodiment, the atomic ratio of the desired product molecular formula is 1:1, the crystallizing raw materials are PbBr2 and CsBr, and the mass ratio of PbBr2 and CsBr is 36.7g:21.2g.

[0045] S2. Place the crystallization container 30 containing the raw materials and the heat preservation and stabilization device 20 in the high temperature zone of the crystallization chamber 12, wherein the crystallization container 30 passes through the heat preservation and stabilization device 20, the heat preservation and stabilization device 20 is located above the crystallization container 30, the lower part of the crystallization container 30 is located below the heat preservation and stabilization device 20, and the lowest point of the heat preservation and stabilization device 20 is higher than the lowest point of the high temperature zone. S3. The heating device heats the furnace body to raise the temperature so that the high temperature zone reaches the first target temperature within 8 hours and the low temperature zone reaches the second target temperature within 8 hours; in a specific embodiment, the first target temperature of the high temperature zone can be 650°C and the second target temperature of the low temperature zone can be 600°C.

[0046] S4. The crystallization container 30 is kept in the high-temperature zone for a preset time so that the crystallization raw material in the lower part of the crystallization container 30 reaches the molten state; in a specific embodiment, the preset time can be 24 hours.

[0047] S5. The crystallization container 30 moves from the high temperature zone to the low temperature zone at a preset speed. The molten raw material gradually crystallizes after reaching the low temperature zone, wherein the high temperature zone is located above the low temperature zone. In a specific embodiment, the preset speed can be 1 mm / h.

[0048] S6. After the raw material in the crystallization container 30 crystallizes, the induction coil stops heating the furnace body and allows the furnace body to gradually cool down to room temperature.

[0049] Throughout the crystallization process, the heat-insulating and stabilizing device 20 remains in the high-temperature zone, thus preventing excessive movement of the quartz tube within the crystallization chamber 12 and ensuring effective crystallization. Figure 1 As shown, Figure 1 The diagram shows the non-initial state of the heat preservation and stabilization device 20 and the crystallization container 30. That is, in... Figure 1 In this process, the lower part of the crystallization container 30 has moved to the low-temperature zone. The crystal growth method of this embodiment also has the advantages mentioned above, which will not be repeated here.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A Bridgeman crystal growth furnace, characterized in that, Includes heating furnace and heat preservation and stabilization device; The heating furnace is provided with a crystallization chamber, which is a cylindrical cavity. The heat preservation and stabilization device is located at one end of the crystallization chamber. The heat preservation and stabilization device is cylindrical and is coaxially arranged with the crystallization chamber. The heat preservation and stabilization device is used to allow the crystallization container to pass through and to limit the crystallization container.

2. The Bridgeman crystal growth furnace according to claim 1, characterized in that, The heat preservation and stabilization device includes a circular tube body, which is coaxially arranged with the crystallization cavity. The circular tube body is provided with a limiting cavity and a vacuum cavity. The limiting cavity is a cylindrical cavity and is coaxially arranged with the crystallization cavity. The limiting cavity is used to allow the crystallization container to pass through and to limit the crystallization container. The vacuum cavity is arranged around the limiting cavity.

3. The Bridgeman crystal growth furnace according to claim 2, characterized in that, The vacuum cavity is filled with a heat-insulating medium, which includes at least one of quartz, ceramic, and porous materials.

4. The Bridgeman crystal growth furnace according to claim 2, characterized in that, The main body of the tube is a transparent tube.

5. The Bridgeman crystal growth furnace according to claim 2, characterized in that, The distance between the outer wall of the circular tube body and the inner wall of the crystallization cavity is D1, where 0 < D1 ≤ 2 mm; The limiting cavity is a cylindrical cavity, the crystallization container includes a quartz tube, and the distance between the inner wall of the limiting cavity and the outer wall of the quartz tube is D2, where 0 < D2 ≤ 1 mm; The ratio of the height of the main body of the circular tube to its outer diameter is R1, and the ratio of the height of the main body of the circular tube to the length of the quartz tube is R2, wherein 1≤R1 and R2≤1 / 2.

6. The Bridgeman crystal growth furnace according to claim 1, characterized in that, The heating furnace includes a furnace body and a heating device. The heating device is installed on the furnace body. The furnace body is provided with the crystallization chamber. The furnace body includes a high-temperature zone and a low-temperature zone. The high-temperature zone is located in the upper part of the furnace body, and the low-temperature zone is located in the lower part of the furnace body.

7. The Bridgeman crystal growth furnace according to claim 1, characterized in that, It also includes a heat insulation plug, the crystallization cavity is a cylindrical through hole, the heat insulation plug is detachably disposed at the bottom of the crystallization cavity, the heat preservation and stabilization device is located at the upper part of the crystallization cavity and at the upper part of the crystallization container, and the lower part of the crystallization container is located between the heat preservation and stabilization device and the heat insulation plug.

8. The Bridgeman crystal growth furnace according to claim 2, characterized in that, It also includes a settling machine and a settling line. The heat preservation and stabilization device also includes a fixing part, which is located on the upper part of the circular tube body. The settling machine is located above the heating furnace. One end of the settling line is connected to the settling machine, and the other end of the settling line is connected to the fixing part and the crystallization container.

9. The Bridgeman crystal growth furnace according to claim 8, characterized in that, The fixing part is a ring, and the upper end of the crystallization container is provided with a circular hole. The other end of the settling line passes through the ring and the circular hole in sequence so that the other end of the settling line is connected to the fixing part and the crystallization container.

10. A crystal growth method using the Bridgeman crystal growth furnace according to claim 1, characterized in that, include: Select the corresponding mass of crystallizing raw materials according to the atomic ratio of the desired product molecular formula, mix the crystallizing raw materials evenly, grind them, and place them in the lower part of the crystallization container; The crystallization container containing the crystallization raw material and the heat preservation and stabilization device are placed in the high-temperature zone of the crystallization chamber, wherein the crystallization container passes through the heat preservation and stabilization device, the heat preservation and stabilization device is located above the crystallization container, the lower part of the crystallization container is located below the heat preservation and stabilization device, and the lowest point of the heat preservation and stabilization device is higher than the lowest point of the high-temperature zone. The heating furnace is heated to raise the temperature so that the high-temperature zone reaches a first target temperature and the low-temperature zone reaches a second target temperature; The crystallization container is maintained in the high-temperature zone for a preset time so that the crystallization raw material in the lower part of the crystallization container reaches a molten state; The crystallization container moves from the high-temperature zone to the low-temperature zone at a preset speed. The molten raw material gradually crystallizes after reaching the low-temperature zone. The high-temperature zone is located above the low-temperature zone. Once the raw material in the crystallization container has crystallized, heating of the furnace is stopped, and the furnace is gradually cooled to room temperature.

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