Czochralski method crystal growth device

Abstract

The embodiment of the utility model provides a Czochralski method crystal growth device, and relates to the technical field of crystal growth. The Czochralski method crystal growth device comprises a furnace body, a crucible, a first magnetic field device, a seed rod and a second magnetic field device, the crucible is arranged in the furnace body, and the first magnetic field device is arranged on the outer side of the crucible in a surrounding mode and located in the furnace body. The seed rod is arranged in the furnace body and is spaced from the crucible; the second magnetic field device is arranged on the seed crystal rod and is positioned in the furnace body; wherein the first magnetic field device is used for generating a magnetic field and acting on a melt in the crucible; the second magnetic field device is used for generating a magnetic field and acting on a growth interface of the melt. The Czochralski method crystal growth device can effectively inhibit convection of melt, so that solute distribution is uniform, and crystal defects are reduced; and the crystal structure can be optimized, and accurate regulation and control of solute are realized, so that the quality and the performance of the crystal are integrally improved.

Description

Technical Field

[0001] This utility model relates to the field of crystal growth technology, and more specifically, to a Czochralski crystal growth apparatus. Background Technology

[0002] The Czochralski method, also known as the Czochralski process, is a traditional single crystal growth method for preparing large-size, high-quality single crystals from a melt. The crystal growth process includes steps such as melting, crystal pulling, shoulder formation, constant diameter formation, and tailing. Common crystals such as silicon single crystals, germanium single crystals, lithium niobate, lithium tantalate, gallium oxide, and sapphire are typically grown using the Czochralski method.

[0003] However, in the traditional Czochralski method for crystal preparation, the distribution of solute is often uneven due to factors such as natural convection and thermal convection of the melt. This leads to problems such as stress and defects inside the crystal. Furthermore, the microstructure of the crystal is difficult to control precisely during the growth process, which is not conducive to maintaining compositional consistency and structural integrity, resulting in poor overall quality and performance of the crystal. Utility Model Content

[0004] The purpose of this invention is to provide a Czochralski crystal growth apparatus that can effectively suppress melt convection, make solute distribution uniform, and reduce crystal defects; and can optimize crystal structure and achieve precise control of solute, thereby improving the overall quality and performance of the crystal.

[0005] The embodiments of this utility model are implemented as follows:

[0006] In a first aspect, this utility model provides a Czochralski crystal growth apparatus, comprising:

[0007] Furnace body;

[0008] A crucible, which is disposed inside the furnace body;

[0009] A first magnetic field device is arranged around the outside of the crucible and located inside the furnace body;

[0010] A seed crystal rod, wherein the seed crystal rod is disposed inside the furnace body and spaced apart from the crucible; and

[0011] A second magnetic field device is disposed on the seed crystal rod and located inside the furnace body;

[0012] The first magnetic field device is used to generate a magnetic field and act on the melt in the crucible; the second magnetic field device is used to generate a magnetic field and act on the growth interface of the melt.

[0013] In an optional embodiment, the second magnetic field device includes a helical coil and a fixed sleeve, the fixed sleeve being fitted onto the end of the seed crystal rod near the crucible, and the helical coil being fitted onto the fixed sleeve.

[0014] In an optional embodiment, the outer wall of the fixed sleeve is provided with a first spiral groove, and the spiral tube coil is disposed in the first spiral groove.

[0015] In an optional embodiment, the second magnetic field device further includes a power line and a signal line, both of which are sleeved on the seed crystal rod and connected to the helical coil.

[0016] In an optional embodiment, a second spiral groove is formed on the outer wall of the seed crystal rod, and the power line is disposed in the second spiral groove; and / or,

[0017] The outer wall of the seed crystal rod is provided with a third spiral groove, and the signal line is disposed in the third spiral groove.

[0018] In an optional embodiment, the distance between the bottom of the second magnetic field device and the top of the crucible is 1cm to 10cm.

[0019] In an optional embodiment, the magnetic field strength produced by the second magnetic field device is 100 Gs to 1000 Gs.

[0020] In an optional embodiment, the Czochralski crystal growth apparatus further includes a heat insulation hood, which is disposed inside the furnace and covers the opening of the crucible to form a crystal growth chamber between the heat insulation hood and the crucible.

[0021] The seed crystal rod is inserted through the heat insulation cover, and at least a portion of the seed crystal rod is located within the crystal growth chamber, while the second magnetic field device is located within the crystal growth chamber.

[0022] In an optional embodiment, the Czochralski crystal growth apparatus further includes a heat-insulating barrel located inside the furnace, the crucible disposed inside the heat-insulating barrel, and the first magnetic field device disposed around the outside of the heat-insulating barrel.

[0023] In an optional embodiment, the Czochralski crystal growth apparatus further includes a particle insulation layer, which is wrapped around the outer wall of the crucible and disposed inside the insulation container.

[0024] The beneficial effects of this utility model embodiment include:

[0025] The Czochralski crystal growth apparatus includes a furnace body, a crucible, a first magnetic field device, a seed crystal rod, and a second magnetic field device. The crucible is disposed inside the furnace body, and the first magnetic field device is disposed around the outside of the crucible and located inside the furnace body. The seed crystal rod is disposed inside the furnace body and spaced apart from the crucible. The second magnetic field device is disposed on the seed crystal rod and located inside the furnace body. The first magnetic field device is used to generate a magnetic field and act on the melt inside the crucible. The second magnetic field device is used to generate a magnetic field and act on the growth interface of the melt.

[0026] The first magnetic field device is used for macroscopic control of crystal growth. Specifically, different magnetic fields can be applied at different stages of crystal growth. This magnetic field can generate Lorentz forces on charged particles in the melt, affecting the convection state of the melt, such as influencing natural convection, thereby effectively suppressing melt convection, making the solute distribution more uniform, and making the temperature distribution in the melt more uniform, reducing crystal growth defects caused by temperature gradients. Simultaneously, the second magnetic field device is used for microscopic control of crystal growth. Specifically, different magnetic fields can be applied at different stages of crystal growth, acting on the crystal growth interface. This magnetic field changes the energy field near the seed crystal, affecting the crystal nucleation process and promoting more ordered crystal growth; it also precisely controls the distribution of solute at the microscale to meet the crystal's specific performance requirements, enabling precise control of doping concentration, thereby optimizing the crystal's microstructure and improving its stability.

[0027] In other words, by working together with the first magnetic field device and the second magnetic field device, the crystal growth process can be optimized at both the macroscopic and microscopic levels, reducing various defects in the crystal and thus improving the overall quality and performance of the crystal. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A schematic diagram of the structure of the Czochralski crystal growth apparatus provided in this embodiment of the present invention;

[0030] Figure 2 A flowchart illustrating the method for controlling the growth of Czochralski crystals according to an embodiment of this utility model;

[0031] Figure 3 for Figure 2 Flowchart of the sub-steps of step S10;

[0032] Figure 4 for Figure 2 Flowchart of the sub-steps of step S20;

[0033] Figure 5 for Figure 4 A schematic diagram of the magnetic field direction in neutron step S21;

[0034] Figure 6 for Figure 4 A schematic diagram of the magnetic field direction in the neutron step S22.

[0035] Icons: 100-Czochralski crystal growth apparatus; 10-Furnace body; 20-Crucible; 30-First magnetic field device; 40-Seed crystal rod; 50-Second magnetic field device; 51-Spiral coil; 52-Fixing sleeve; 521-First spiral groove; 53-Power line; 54-Signal line; 60-Insulation cover; 70-Insulation barrel; 80-Particle insulation layer; 200-Melted material; 300-Crystal; 310-Crystallization face; 400-Seed crystal. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0038] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0039] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and 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 this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0040] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0041] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0042] As described in the background section, in the traditional Czochralski method for crystal preparation, the distribution of solute is often uneven due to factors such as natural convection and thermal convection of the melt. This leads to problems such as stress and defects inside the crystal. Furthermore, the microstructure of the crystal is difficult to control precisely during the growth process, which is not conducive to maintaining compositional consistency and structural integrity, resulting in poor overall quality and performance of the crystal.

[0043] Based on this, please refer to Figures 1-6 This invention provides a Czochralski crystal growth apparatus 100 and a control method thereof, which can effectively improve the aforementioned technical problems. Specifically, it can effectively suppress the convection of the melt 200, make the solute distribution uniform, and reduce defects in the crystal 300; furthermore, it can optimize the structure of the crystal 300 and achieve precise control of the solute, thereby improving the overall quality and performance of the crystal 300. The following will provide a detailed description of the Czochralski crystal growth apparatus 100 and the control method thereof.

[0044] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the Czochralski crystal growth apparatus 100 provided in this embodiment, combined with... Figure 1 The Czochralski crystal growth apparatus 100 includes a furnace body 10, a crucible 20, a first magnetic field device 30, a seed crystal rod 40, and a second magnetic field device 50. The crucible 20 is disposed inside the furnace body 10, and the first magnetic field device 30 is disposed around the outside of the crucible 20 and located inside the furnace body 10. The seed crystal rod 40 is disposed inside the furnace body 10 and spaced apart from the crucible 20. The second magnetic field device 50 is disposed on the seed crystal rod 40 and located inside the furnace body 10. The first magnetic field device 30 is used to generate a magnetic field and acts on the melt 200 inside the crucible 20. The second magnetic field device 50 is used to generate a magnetic field and acts on the growth interface of the melt 200.

[0045] It should be noted that the first magnetic field device 30 is used to macroscopically control the growth of crystal 300. Specifically, different magnetic fields can be applied to different growth stages of crystal 300. This magnetic field can generate Lorentz force on charged particles in melt 200, affecting the convection state of melt 200, such as affecting the natural convection of melt 200, thereby effectively suppressing the convection of melt 200, making the solute distribution uniform, and making the temperature distribution in melt 200 more uniform, reducing crystal 300 growth defects caused by temperature gradient.

[0046] Meanwhile, the second magnetic field device 50 is used to microscopically control the growth of crystal 300. Specifically, different magnetic fields can be applied to different growth stages of crystal 300, which can act on the growth interface of crystal 300. This magnetic field will change the energy field near seed crystal 400, affect the nucleation process of crystal 300, and promote more orderly growth of crystal 300. Furthermore, it can precisely control the distribution of solute at the microscale to meet the specific performance requirements of crystal 300, and can achieve precise control of doping concentration, thereby optimizing the microstructure of crystal 300 and improving the stability of crystal 300.

[0047] In other words, through the coordinated operation of the first magnetic field device 30 and the second magnetic field device 50, the growth process of the crystal 300 can be optimized at both the macroscopic and microscopic levels, reducing various defects in the crystal 300 and thus improving the overall quality and performance of the crystal 300.

[0048] It should be noted that, in this embodiment, the first magnetic field device 30 may specifically include an induction heating coil. By energizing the induction heating coil, a magnetic field is generated around the crucible 20. Furthermore, different magnetic field magnitudes can be achieved by adjusting the power, thereby corresponding to different growth stages, so as to achieve macroscopic control of the growth of the crystal 300, and work together with the second magnetic field device 50 to improve the quality and performance of the crystal 300 growth.

[0049] Furthermore, it should be noted that the growth interface of crystal 300 refers to the boundary region between crystal 300 and melt 200 during the growth process of crystal 300. This interface is the core region for crystal 300 growth, and its fluctuations and morphology have a significant impact on the quality of crystal 300. Therefore, by applying magnetic fields of different magnitudes and directions to the growth interface at different stages of crystal 300 growth, the quality and performance of crystal 300 growth can be improved.

[0050] Specifically, the second magnetic field device 50 includes a helical coil 51 and a fixing sleeve 52. The fixing sleeve 52 is fitted onto the end of the seed crystal rod 40 near the crucible 20, and the helical coil 51 is fitted onto the fixing sleeve 52. It is easy to understand that the helical coil 51 can be connected to an external power source. By changing the direction and magnitude of the current through the power source, the magnitude and direction of the magnetic field can be flexibly adjusted to meet the different magnetic field requirements at different growth stages. At the same time, by setting the fixing sleeve 52, the helical coil 51 can be easily fixed, improving the stability of the magnetic field generated by the helical coil 51.

[0051] It should be noted that the material of the fixing sleeve 52 can be ceramic, which has the characteristics of chemical corrosion resistance, high temperature resistance, wear resistance, high strength, stability and toughness, and can better meet the usage environment of crystal 300 growth.

[0052] In order to better fix the helical coil 51 and further improve the stability of the magnetic field generated by the helical coil 51, in this embodiment, a first helical groove 521 is provided on the outer wall of the fixing sleeve 52, and the helical coil 51 is disposed in the first helical groove 521.

[0053] Furthermore, to facilitate the connection of the helical coil 51 to an external power supply and other devices, the second magnetic field device 50 also includes a power line 53 and a signal line 54. Both the power line 53 and the signal line 54 are sleeved on the seed crystal rod 40 and connected to the helical coil 51. It is easy to understand that the power line 53 is used for connection to the power supply, and the signal line 54 is used for transmitting control signals, ensuring a secure connection and good insulation performance to prevent leakage that could affect the growth of the crystal 300.

[0054] Furthermore, to precisely control the current output by the power supply, the Czochralski crystal growth apparatus 100 also includes a controller (not shown in the figure), which is electrically connected to the power supply. It is understood that the controller can be a computer-programmed power controller capable of sending corresponding instructions according to the growth stage of the crystal 300, thereby precisely controlling the power supply to change the magnitude and direction of the current.

[0055] Similarly, in order to better install the power line 53 and the signal line 54, in this embodiment, the outer side wall of the seed crystal rod 40 is provided with a second spiral groove and a third spiral groove (not shown in the figure), the power line 53 is disposed in the second spiral groove, and the signal line 54 is disposed in the third spiral groove.

[0056] It should be noted that the second and third spiral grooves can be connected to form a single spiral groove, and the power line 53 and signal line 54 are both located within this spiral groove; of course, the second and third spiral grooves can also be spaced apart, and the power line 53 and signal line 54 can be installed independently without affecting each other.

[0057] Optionally, the distance between the bottom of the second magnetic field device 50 and the top of the crucible 20 is 1cm to 10cm. Specifically, in this embodiment, the distance between the bottom of the helical coil 51 and the top of the crucible 20 is 1cm to 10cm. For example, the distance between them can be 1cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm, 9cm, 10cm, etc. Within this range, the magnetic field generated by the second magnetic field device 50 has a better effect on the melt 200, that is, the quality and performance of the crystal 300 growth are better.

[0058] Optionally, the magnetic field strength produced by the second magnetic field device 50 is between 100 Gs and 1000 Gs. For example, the specific magnetic field strength can be 100 Gs, 200 Gs, 300 Gs, 400 Gs, 500 Gs, 600 Gs, 700 Gs, 800 Gs, 900 Gs, 1000 Gs, etc. Within this range, the magnetic field generated by the second magnetic field device 50 has a better effect on the melt 200, that is, the quality and performance of the crystal 300 growth are better.

[0059] Please continue to combine Figure 1 The Czochralski crystal growth apparatus 100 also includes a heat insulation cover 60, which is disposed inside the furnace body 10 and covers the opening of the crucible 20 to form a crystal growth chamber 300 between the heat insulation cover 60 and the crucible 20; wherein, the seed crystal rod 40 passes through the heat insulation cover 60, and at least a portion of the seed crystal rod 40 is located inside the crystal growth chamber 300, and the second magnetic field device 50 is located inside the crystal growth chamber 300.

[0060] By setting up the heat insulation cover 60, the heat insulation function can be achieved, which ensures the temperature stability during the pulling and rotating of the crystal 300, reduces the problem of crystal 300 growth defects caused by temperature gradient during the pulling process, and thus improves the quality and performance of crystal 300 growth.

[0061] Furthermore, the Czochralski crystal growth apparatus 100 also includes a heat-insulating container 70, which is located inside the furnace body 10. The crucible 20 is placed inside the heat-insulating container 70, and the first magnetic field device 30 is arranged around the outside of the heat-insulating container 70. It is easy to understand that by setting up the heat-insulating container 70, the crucible 20 can be kept warm, preventing the heat of the melt 200 inside the crucible 20 from being lost, thereby ensuring the stable growth of the crystal 300.

[0062] Based on the above, the Czochralski crystal growth apparatus 100 provided in this embodiment also includes a particle insulation layer 80, which is wrapped around the outer wall of the crucible 20 and disposed inside the insulation barrel 70.

[0063] It should be noted that, firstly, the granular insulation layer 80 can further prevent heat conduction and reduce the paths for heat loss; secondly, there may be localized temperature unevenness inside the insulation container 70, and the granular insulation layer 80 can fill the gap between the insulation container 70 and the crucible 20, making the temperature distribution more uniform and playing a fine-tuning role in the temperature field, compensating for any temperature distribution defects that may occur in the insulation container 70; in addition, the granular insulation layer 80 has a buffering effect. During the operation of the growth device, there may be slight displacement or vibration due to factors such as thermal expansion. The granular insulation layer 80 can buffer these effects and avoid significant interference with the crystal 300 growth environment; thereby further improving the quality and performance of crystal 300 growth.

[0064] Please refer to Figure 2 , Figure 2 This is a flowchart of the Czochralski crystal growth control method provided in this embodiment, combined with... Figure 2 The method for controlling the growth of Czochralski crystals is implemented using a Czochralski crystal growth apparatus 100, which includes:

[0065] Step S10: Activate the first magnetic field device 30 to apply a magnetic field to the melt 200 inside the crucible 20;

[0066] Step S20: Start the second magnetic field device 50 to apply a magnetic field to the growth interface of the melt 200.

[0067] As is easily understood, this Czochralski crystal growth control method, by simultaneously setting magnetic field devices around the crucible 20 and near the growth interface of the crystal 300, can work in synergy. The area around the crucible 20 provides a stable macroscopic environment, suppressing the overall convection of the melt 200 and the macroscopic inhomogeneity of the solute, while the magnetic field at the growth interface optimizes the growth process of the crystal 300 at the microscopic level. It can jointly optimize the growth process of the crystal 300 at both the macroscopic and microscopic levels, stabilize the growth interface of the crystal 300, reduce various defects of the crystal 300, optimize the microstructure of the crystal 300, and thus improve the overall quality and performance of the crystal 300.

[0068] For details, please refer to Figure 3 , Figure 3 for Figure 2 The flowchart of the sub-steps of step S10, combined with... Figure 3 Step S10 includes:

[0069] Sub-step S11: During the polycrystalline material melting stage, the first magnetic field device 30 is activated to apply a magnetic field of the first magnetic field strength to the polycrystalline material to obtain melt 200.

[0070] Sub-step S12: During the shoulder formation stage of the crystal, the first magnetic field device 30 is activated, and based on the first magnetic field strength, a gradually increasing magnetic field strength is applied to the melt 200 until the magnetic field strength at the end of the shoulder formation is the second magnetic field strength.

[0071] Sub-step S13: During the constant diameter stage of the crystal, the first magnetic field device 30 is activated to apply a magnetic field of the second magnetic field strength to the melt 200;

[0072] Sub-step S14: In the final stage of crystal formation, the first magnetic field device 30 is activated to apply a magnetic field of the third magnetic field strength to the melt 200.

[0073] The first magnetic field strength is less than the second magnetic field strength, and the second magnetic field strength is greater than the third magnetic field strength.

[0074] In other words, during the polycrystalline material melting stage of the crystal, the first magnetic field strength acts on the polycrystalline material. Under the action of the magnetic field, the eddy currents generated inside will melt the polycrystalline material. Then, during the shoulder formation stage of the crystal, the magnetic field strength is continuously increased based on the first magnetic field strength. A slightly stronger magnetic field will generate a larger Lorentz force on the charged particles in the melt 200, thereby accelerating the convection of the melt 200, making the temperature distribution more uniform, which is conducive to the uniform shoulder formation of the crystal 300. Until the end of the shoulder formation stage, the magnetic field will increase to the second magnetic field strength.

[0075] During the constant diameter stage of the crystal, the magnetic field strength remains consistent with that during the shoulder formation stage, ensuring a stable growth environment that allows the solute to be transported to the crystal 300 growth interface at a stable rate, enabling the crystal 300 to grow continuously and uniformly.

[0076] It should be noted that the third magnetic field strength can be set by gradually decreasing the magnetic field strength based on the second magnetic field strength. In this way, by gradually reducing the magnetic field strength in the final stage of crystal formation, the convection of the melt 200 can be slowed down. This can prevent tail defects of the crystal 300 caused by excessive convection or excessive temperature in the final stage, thereby ensuring the quality and performance of the prepared crystal 300.

[0077] For details, please refer to Figure 4 , Figure 4 for Figure 2 The flowchart of the sub-steps in step S20, combined with... Figure 4 Step S20 includes:

[0078] Sub-step S21: In the seed crystal introduction stage, the second magnetic field device 50 is activated to apply a magnetic field of the fourth magnetic field strength to the growth interface of the melt 200, and the direction of the magnetic field is away from the growth interface.

[0079] Sub-step S22: During the crystal growth stage, the second magnetic field device 50 is activated to apply a magnetic field of the fifth magnetic field strength to the growth interface of the melt 200, and the direction of the magnetic field is close to the growth interface.

[0080] The fourth magnetic field strength is less than the fifth magnetic field strength, and the growth stages include the shoulder formation stage, the constant diameter stage, and the finishing stage. In other words, the magnetic field strength is increased from the seed crystal introduction stage to the crystal growth stage, and the magnetic field directions are opposite in the two stages.

[0081] Specifically, please refer to Figure 5 and Figure 6 , Figure 5 for Figure 4 A schematic diagram of the magnetic field direction in the neutron step S21. Figure 6 for Figure 4 A schematic diagram of the magnetic field direction in the neutron step S22, which is easy to understand. Figure 5 The direction of the magnetic field shown is away from the crystal plane 310, which can also be understood as the upward direction; Figure 6 The direction of the magnetic field shown is close to the crystal plane 310, which can also be understood as the downward direction.

[0082] Combination Figures 4-6 During the seed crystal introduction stage, by setting a smaller magnetic field strength, it is possible to avoid excessive interference from the magnetic field to the seed crystal 400. At the same time, by setting this upward magnetic field, that is, the direction of the magnetic field is away from the crystal plane 310, it is possible to accelerate solute convection, so that the solute can quickly accumulate at the growth interface and promote the rapid growth of crystal 300.

[0083] During the crystal growth stage, by setting a larger magnetic field strength, the crystal lattice structure of crystal 300 can grow more orderly under a suitable magnetic field. Simultaneously, by setting this downward magnetic field, i.e., changing the direction of the magnetic field to move it towards the crystallization plane 310, convection of melt 200 can be suppressed, which is beneficial for the stable growth of crystal 300. It is easy to understand that the combined effect of sub-steps S21 and S22 can further improve the quality and performance of the prepared crystal 300.

[0084] In summary, the embodiments of this utility model provide a Czochralski crystal growth apparatus 100 and a control method. The Czochralski crystal growth apparatus 100 includes a furnace body 10, a crucible 20, a first magnetic field device 30, a seed crystal rod 40, and a second magnetic field device 50. The crucible 20 is disposed inside the furnace body 10, and the first magnetic field device 30 is disposed around the outside of the crucible 20 and located inside the furnace body 10. The seed crystal rod 40 is disposed inside the furnace body 10 and spaced apart from the crucible 20. The second magnetic field device 50 is disposed on the seed crystal rod 40 and located inside the furnace body 10. The first magnetic field device 30 is used to generate a magnetic field and acts on the melt 200 inside the crucible 200. The second magnetic field device 50 is used to generate a magnetic field and acts on the growth interface of the melt 200.

[0085] The first magnetic field device 30 is used for macroscopic control of crystal 300 growth. Specifically, different magnetic fields can be applied to different growth stages of crystal 300. This magnetic field can generate Lorentz forces on charged particles in melt 200, affecting the convection state of melt 200, such as affecting natural convection, thereby effectively suppressing convection in melt 200, making the solute distribution more uniform, and making the temperature distribution in melt 200 more uniform, reducing crystal 300 growth defects caused by temperature gradients. Simultaneously, the second magnetic field device 50 is used for microscopic control of crystal 300 growth. Specifically, different magnetic fields can be applied to different growth stages of crystal 300, acting on the growth interface of crystal 300. This magnetic field changes the energy field near seed crystal 400, affecting the nucleation process of crystal 300, promoting more orderly growth of crystal 300; and precisely controlling the distribution of solute at the microscale to meet the specific performance requirements of crystal 300, enabling precise control of doping concentration, thereby optimizing the microstructure of crystal 300 and improving its stability. In other words, through the coordinated operation of the first magnetic field device 30 and the second magnetic field device 50, the growth process of the crystal 300 can be optimized at both the macroscopic and microscopic levels, reducing various defects in the crystal 300 and thus improving the overall quality and performance of the crystal 300.

[0086] The Czochralski crystal growth control method utilizes a Czochralski crystal growth apparatus 100, comprising: activating a first magnetic field device 30 and applying a magnetic field to the melt 200 within the crucible 20; and activating a second magnetic field device 50 and applying a magnetic field to the growth interface of the melt 200. This Czochralski crystal growth control method, by simultaneously placing magnetic field devices around the crucible 20 and near the crystal 300 growth interface, enables coordinated operation. The area around the crucible 20 provides a stable macroscopic environment, suppressing overall convection of the melt 200 and macroscopic inhomogeneities of the solute. The magnetic field at the growth interface optimizes the crystal 300 growth process at the microscopic level. This method optimizes the crystal 300 growth process at both the macroscopic and microscopic levels, stabilizes the crystal 300 growth interface, reduces various defects in the crystal 300, optimizes the microstructure of the crystal 300, and thus improves the overall quality and performance of the crystal 300.

[0087] The above description is merely a specific embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A Czochralski crystal growth apparatus, characterized in that, include: Furnace body (10); A crucible (20) is disposed inside the furnace body (10); A first magnetic field device (30) is arranged around the outside of the crucible (20) and located inside the furnace body (10); Seed crystal rod (40), the seed crystal rod (40) is disposed inside the furnace body (10) and spaced apart from the crucible (20); as well as The second magnetic field device (50) is disposed on the seed crystal rod (40) and located inside the furnace body (10); The first magnetic field device (30) is used to generate a magnetic field and act on the melt (200) in the crucible (20); the second magnetic field device (50) is used to generate a magnetic field and act on the growth interface of the melt (200).

2. The Czochralski crystal growth apparatus according to claim 1, characterized in that, The second magnetic field device (50) includes a helical coil (51) and a fixed sleeve (52). The fixed sleeve (52) is sleeved on one end of the seed crystal rod (40) near the crucible (20), and the helical coil (51) is sleeved on the fixed sleeve (52).

3. The Czochralski crystal growth apparatus according to claim 2, characterized in that, The outer wall of the fixed sleeve (52) is provided with a first spiral groove (521), and the spiral tube coil (51) is disposed in the first spiral groove (521).

4. The Czochralski crystal growth apparatus according to claim 2, characterized in that, The second magnetic field device (50) also includes a power line (53) and a signal line (54), both of which are sleeved on the seed crystal rod (40) and are connected to the helical coil (51).

5. The Czochralski crystal growth apparatus according to claim 4, characterized in that, The outer wall of the seed crystal rod (40) is provided with a second spiral groove, and the power line (53) is disposed in the second spiral groove; and / or, The outer wall of the seed crystal rod (40) is provided with a third spiral groove, and the signal line (54) is disposed in the third spiral groove.

6. The Czochralski crystal growth apparatus according to claim 1, characterized in that, The distance between the bottom of the second magnetic field device (50) and the top of the crucible (20) is 1cm to 10cm.

7. The Czochralski crystal growth apparatus according to claim 1, characterized in that, The magnetic field strength produced by the second magnetic field device (50) is 100Gs to 1000Gs.

8. The Czochralski crystal growth apparatus according to claim 1, characterized in that, The Czochralski crystal growth apparatus (100) further includes a heat insulation cover (60), which is disposed inside the furnace body (10) and covers the opening of the crucible (20) to form a crystal (300) growth chamber between itself and the crucible (20). The seed crystal rod (40) is inserted through the heat insulation cover (60), and at least a portion of the seed crystal rod (40) is located in the crystal (300) growth chamber, and the second magnetic field device (50) is located in the crystal (300) growth chamber.

9. The Czochralski crystal growth apparatus according to claim 1, characterized in that, The Czochralski crystal growth apparatus (100) also includes a heat preservation barrel (70), which is located inside the furnace body (10). The crucible (20) is disposed inside the heat preservation barrel (70), and the first magnetic field device (30) is disposed around the outside of the heat preservation barrel (70).

10. The Czochralski crystal growth apparatus according to claim 9, characterized in that, The Czochralski crystal growth apparatus (100) further includes a particle insulation layer (80), which is wrapped around the outer wall of the crucible (20) and disposed inside the insulation barrel (70).

Images