Growth device and method suitable for mass production of crystals by flux method / liquid phase method

Abstract

The invention discloses a growth device and method suitable for mass production of crystals by a fluxing agent method / liquid phase method. The growth method comprises the following steps: putting a seed crystal and a liquid phase growth raw material into a first growth container, putting the seed crystal into a second growth container, keeping the temperature of a first temperature zone at a first temperature T1, keeping the temperature of a second temperature zone at a second temperature T2, keeping the temperature of a third temperature zone at a third temperature T3, other growth conditions required by crystal growth are provided in the growth chamber; and rotating the rotary lifting frame to drive the second growth container and the seed crystal carried by the second growth container to rotate along a selected rotating track, so that the second growth container and the seed crystal carried by the second growth container are repeatedly transferred between the first temperature zone and the second temperature zone and are repeatedly immersed into the liquid phase growth raw material in the first growth container. The method can be used for industrially producing high-quality single crystals such as gallium nitride with different sizes in batches, and the production efficiency and quality are improved.

Description

Technical Field

[0001] The present invention particularly relates to a growth device and method suitable for batch production of crystals using a flux method / liquid phase method, and belongs to the technical field of semiconductor crystal growth. Background Art

[0002] Gallium nitride (GaN) has broad application prospects in optoelectronics and power devices due to its excellent properties, including wide bandgap, high electron mobility, and high breakdown electric field. The flux method has shown significant advantages in preparing large-scale, extremely low dislocation density GaN single crystals.

[0003] However, the current growth of gallium nitride using the flux method is all monolithic growth. In a growth device, a crucible is placed, and a gallium nitride seed crystal is placed in the crucible to conduct a closed growth experiment. This method has a low growth rate, resulting in high time cost and low yield. For example, CN118109897A discloses a crystal growth device for growing nitride single crystals using the flux method, which is equipped with a pulling device on the top of the flux method growth device to pull the crucible in the vertical direction. CN116536758A discloses a device and method for high-pressure flux epitaxial growth of gallium nitride crystals, wherein the heater adopts upper and lower temperature zones for heating, and the crucible containing gallium-sodium mixed metal is placed between the upper and lower heaters. The temperature gradient formed by the upper and lower temperature zones is used to promote the convection of the solution, thereby facilitating the dissolution of nitrogen atoms and their transfer to the substrate at the bottom of the crucible, thereby epitaxially growing a single crystal. CN119041003A discloses a stirring device, growth equipment and growth method for growing GaN single crystals by the flux method. It designs a stirring device for growing crystals by the flux method, and swings the bottom support frame of the crucible along the vertical axis to solve the technical problem that the stirring effect of the existing stirring device for growing GaN single crystals is poor, resulting in a low dissociation rate of N ions and an inability to effectively distribute N ions evenly in the melt. Summary of the Invention

[0004] The main purpose of the present invention is to provide a growth device and method suitable for the flux method / liquid phase method of batch production of crystals, which can industrialize and batch produce high-quality, gallium nitride and other single crystals of different sizes, improve production efficiency and quality, and thus overcome the shortcomings of the existing technology.

[0005] To achieve the aforementioned object of the invention, the technical solutions adopted by the present invention include: A first aspect of an embodiment of the present invention provides a growth apparatus suitable for mass production of crystals using a flux method or a liquid phase method, comprising: A growth chamber, wherein the growth chamber has a first temperature zone, a second temperature zone, and a third temperature zone arranged in sequence from top to bottom along the growth chamber, wherein the first temperature zone has a first temperature T1, the second temperature zone has a second temperature T2, and the third temperature zone has a third temperature T3, where T1<T2>T3; a first growth container with an open top, disposed within the growth chamber, the first growth container being configured to accommodate seed crystals and liquid-phase growth materials, wherein a bottom region of the first growth container is located in the third temperature zone, and a top region of the first growth container is located in the second temperature zone, wherein a temperature difference between the second temperature zone and the third temperature zone can promote convection of the liquid-phase growth materials within the first growth container in a depth direction; A rotating lifting frame and a plurality of second growth containers with open tops are arranged in the growth chamber, and a plurality of second growth containers are arranged on the rotating lifting frame. The second growth containers are used to accommodate seed crystals and liquid-phase growth materials. The rotating lifting frame is used to drive the second growth containers to rotate around its own rotation center, and the second growth containers always maintain a fixed posture during the rotation process, wherein the rotation trajectory of the second growth container is located in the first temperature zone and the second temperature zone, and the size of the second growth container is smaller than that of the first growth container, and the first growth container is located on the rotation trajectory of the second growth container. The second growth container can be repeatedly immersed in the liquid-phase growth material of the first growth container during the rotation process, and while the liquid-phase growth material in the first growth container enters the second growth container, the liquid-phase growth material in the first growth container is disturbed. The first growth container and the seed crystal and liquid-phase growth material located in the first growth container, and the second growth container and the seed crystal and liquid-phase growth material located in the second growth container respectively form independent crystal growth systems.

[0006] A second aspect of an embodiment of the present invention provides a flux method / liquid phase method for batch production of crystal growth, comprising: Providing the aforementioned growth device suitable for the flux method / liquid phase method batch production of crystals; placing a seed crystal and a liquid growth material in the first growth container, placing a seed crystal in the second growth container, maintaining the temperature of the first temperature zone at a first temperature T1, the temperature of the second temperature zone at a second temperature T2, and the temperature of the third temperature zone at a third temperature T3, where T1 < T2 > T3, and providing other growth conditions required for crystal growth in the growth chamber; The rotating lifting frame is rotated to drive the second growth container and the seed crystal carried by it to rotate along the selected rotation trajectory, so that the second growth container and the seed crystal carried by it are repeatedly transferred between the first temperature zone and the second temperature zone, and repeatedly immersed in the liquid-phase growth raw material in the first growth container. At the same time, the liquid-phase growth raw material in the first growth container is disturbed by the repeatedly immersed second growth container, and crystals are grown on the surfaces of the seed crystals in the first growth container and the second growth container by the flux method / liquid phase method.

[0007] Compared with the prior art, the advantages of the present invention include: An embodiment of the present invention provides a growth device suitable for the flux method / liquid phase method of batch production of crystals. By rotating the lifting structure, multiple second growth containers are driven to be repeatedly immersed in the molten metal and repeatedly transferred between the first temperature zone and the second temperature zone. Multiple crystals of different sizes can be grown simultaneously in the same growth chamber, which is conducive to industrialized and efficient production.

[0008] An embodiment of the present invention provides a growth device suitable for the flux method / liquid phase method of batch production of crystals. By rotating the lifting structure, multiple second growth containers are driven to be repeatedly immersed in the molten metal. While the crystals are growing, the molten metal is disturbed to enhance the efficiency of the nitrogen source being transferred from the upper surface of the molten metal to the lower surface.

[0009] The present invention adopts a pulling method to grow small-sized crystals multiple times, and repeatedly transfers between the first temperature zone and the second temperature zone during the growth process of the small-sized crystals, thereby improving the flatness of the crystal surface, reducing crystal warping and cracking, and improving crystal growth efficiency and quality.

[0010] During the crystal growth process of the present invention, the seed crystal is separated from the metal melt in the heating stage to prevent the seed crystal from dissolving back; and the seed crystal is separated from the melt in the cooling stage to prevent polycrystals from forming on the crystal surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic structural diagram of a growth device suitable for batch production of crystals using a flux method / liquid phase method, provided in a typical embodiment of the present invention; Figure 2 This is a schematic structural diagram of a growth system constructed by a second growth container in a growth apparatus suitable for batch production of crystals using a flux method / liquid phase method, provided in a typical embodiment of the present invention; Figure 3 This is a schematic diagram of a portion of the structure of a growth device suitable for batch production of crystals using a flux method / liquid phase method, provided in a typical embodiment of the present invention; Figure 4 1 is a schematic diagram of a process for crystal growth in a typical embodiment of the present invention; Figure 5 is a structural schematic view of a growth device suitable for batch production of crystals by flux method / liquid phase method according to another exemplary embodiment of the present application; Figure 6 is a schematic view of the crystal growth surface morphology before / after growth parameter adjustment according to an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0012] In view of the deficiencies in the prior art, the present inventors have obtained the technical solution of the present application through long-term research and a large number of practices. The technical solution, its implementation process and principles will be further explained as follows.

[0013] A first aspect of an embodiment of the present application provides a growth device suitable for batch production of crystals by flux method / liquid phase method, comprising: a growth chamber, the growth chamber having a first temperature zone, a second temperature zone and a third temperature zone arranged in sequence from top to bottom along an axis of the growth chamber, the first temperature zone having a first temperature T1, the second temperature zone having a second temperature T2, and the third temperature zone having a third temperature T3, T1 a first growth container with an open top, disposed in the growth chamber, the first growth container being used for accommodating a seed crystal and a liquid phase growth material, and a bottom region of the first growth container being located in the third temperature zone and a top region of the first growth container being located in the second temperature zone, a temperature difference between the second temperature zone and the third temperature zone being capable of causing the liquid phase growth material in the first growth container to convect in a vertical direction; a rotating lifting frame and a plurality of second growth containers with open tops, disposed in the growth chamber, the plurality of second growth containers being disposed on the rotating lifting frame, the second growth containers being used for accommodating a seed crystal and a liquid phase growth material, and the rotating lifting frame being used for driving the second growth containers to rotate around a center of rotation of the rotating lifting frame, the second growth containers always maintaining a fixed posture during rotation, wherein a rotation track of the second growth containers is located in the first temperature zone and the second temperature zone, and a size of the second growth containers is smaller than a size of the first growth container, the first growth container being located on the rotation track of the second growth containers, the second growth containers being capable of repeatedly immersing in the liquid phase growth material in the first growth container during rotation, disturbing the liquid phase growth material in the first growth container while causing the liquid phase growth material in the first growth container to enter the second growth containers, and the first growth container and the seed crystal and the liquid phase growth material located in the first growth container, and the second growth container and the seed crystal and the liquid phase growth material located in the second growth container forming independent crystal growth systems, respectively.

[0014] In a more specific embodiment, the growth device suitable for flux method / liquid phase method batch production of crystals includes: a growth furnace, a first heat source, a second heat source, a third heat source and an insulation mechanism. The growth furnace has a closed growth chamber inside. The first heat source, the second heat source, and the third heat source are arranged on the inner wall of the growth chamber in sequence from top to bottom along the axial direction of the growth chamber. The insulation mechanism is arranged between the second heat source and the first heat source and the third heat source, and separates the second heat source from the first heat source and the third heat source. The spaces corresponding to the growth chamber and the first heat source, the second heat source, and the third heat source respectively form the first temperature zone, the second temperature zone, and the third temperature zone.

[0015] Furthermore, the growth device suitable for flux method / liquid phase method batch production of crystals also includes a growth material supply mechanism, which is used to provide liquid phase growth material to the first growth container and provide vapor phase growth material to the growth chamber.

[0016] Furthermore, the first heat source, the second heat source, the third heat source, and the heat insulation mechanism are all annular structures arranged along the circumference of the growth chamber.

[0017] Furthermore, the inner wall surface of the growth chamber is a heat-insulating structure.

[0018] Furthermore, the rotating lifting frame includes a rotating shaft and multiple rotating arms, the rotating arms are fixedly connected to the rotating shaft, the multiple rotating arms are radially distributed with the rotating shaft as the center, the second growth container is rotatably connected to the rotating arms, and the rotating lifting frame can rotate around the rotating shaft.

[0019] Furthermore, the second growth container is connected to the rotary arm via a hinge or pivot connection.

[0020] Furthermore, the axial direction of the rotation axis is parallel to the radial direction of the growth chamber.

[0021] Furthermore, the sizes of the plurality of second growth containers are the same or different, and the sizes include volumes.

[0022] In a more typical embodiment, the growth device suitable for flux method / liquid phase method batch production of crystals also includes: an in-situ monitoring mechanism and a control mechanism, the in-situ monitoring mechanism is arranged outside the growth chamber, and is used to obtain the growth thickness distribution and surface defect distribution of the crystal surface grown in the second growth container, the control mechanism is connected to the in-situ monitoring mechanism, the rotating lifting frame, the first heat source, the second heat source, the third heat source, and the growth raw material supply mechanism, and is used to adjust at least one of the rotation speed of the rotating lifting frame, the temperature field distribution in the growth chamber, and the concentration of the vapor phase growth raw material in the growth chamber.

[0023] Furthermore, the growth furnace is provided with a high-temperature resistant optical window, and the in-situ monitoring mechanism includes a structured light full-field scanner. The structured light full-field scanner scans the crystal growing in the second growth container through the high-temperature resistant optical window, and obtains the growth thickness distribution, surface uniformity and surface defect distribution of the crystal surface.

[0024] A second aspect of an embodiment of the present invention provides a flux method / liquid phase method for batch production of crystal growth, comprising: Providing the aforementioned growth device suitable for the flux method / liquid phase method batch production of crystals; placing a seed crystal and a liquid growth material in the first growth container, placing a seed crystal in the second growth container, maintaining the temperature of the first temperature zone at a first temperature T1, the temperature of the second temperature zone at a second temperature T2, and the temperature of the third temperature zone at a third temperature T3, where T1 < T2 > T3, and providing other growth conditions required for crystal growth in the growth chamber; The rotating lifting frame is rotated to drive the second growth container and the seed crystal carried by it to rotate along the selected rotation trajectory, so that the second growth container and the seed crystal carried by it are repeatedly transferred between the first temperature zone and the second temperature zone, and repeatedly immersed in the liquid-phase growth raw material in the first growth container. At the same time, the liquid-phase growth raw material in the first growth container is disturbed by the repeatedly immersed second growth container, and crystals are grown on the surfaces of the seed crystals in the first growth container and the second growth container by the flux method / liquid phase method.

[0025] Furthermore, the first temperature T1, the second temperature T2, and the third temperature T3∈(700°C~1000°C).

[0026] Furthermore, the flux method / liquid phase method for batch production of crystal growth also includes: changing the growth rate of the crystal by changing the rotation speed of the rotating lifting frame and / or the residence time of the second growth container and the seed crystal carried by it in the liquid phase growth raw material in the first growth container.

[0027] Furthermore, the flux / liquid phase method for batch production of crystal growth includes: adjusting the growth conditions in the growth chamber to change the growth thickness distribution and at least one of the surface defects of the crystal to grow a crystal with uniform thickness distribution and no defects, wherein the growth conditions include the temperature field distribution in the growth chamber, the pressure in the growth chamber, the concentration of the vapor phase growth raw material in the growth chamber, and the residence time of the second growth container and the seed crystal carried by it in the liquid phase growth raw material in the first growth container.

[0028] Furthermore, the flux method / liquid phase method for batch production of crystal growth specifically includes: measuring and obtaining a growth thickness distribution cloud map of the crystal, and adjusting the growth conditions in the growth chamber according to the growth thickness distribution cloud map to grow a crystal with uniform thickness distribution and no defects; Furthermore, the growth method specifically includes: constructing a growth database that shows the correspondence between crystal growth conditions and crystal growth rate, morphology and quality, and adjusting the growth conditions based on the growth thickness distribution data of the crystal obtained by actual measurement.

[0029] Furthermore, the size of the seed crystal in the first growth container is larger than the size of the seed crystal in the second growth container.

[0030] Furthermore, the seed crystals in the plurality of second growth containers have the same or different sizes.

[0031] The following will further explain the technical solution, its implementation process and principles with reference to the accompanying drawings and specific implementation cases.

[0032] Example 1 See also Figure 1-Figure 3 A growth device suitable for mass production of crystals using a flux method or liquid phase method includes: a growth furnace 100, a first heat source 210, a second heat source 220, a third heat source 230, a heat insulation mechanism 300, a rotating lifting frame 400, a first growth container 510 with an open top, a plurality of second growth containers 520 with open tops, and a growth material supply mechanism. The growth furnace 100 includes a sealed growth chamber 110. A first heat source 210, a second heat source 220, and a third heat source 230 are sequentially spaced from top to bottom on the inner wall of the growth chamber 110 along the axial direction of the growth chamber 110 (the axial direction of the growth furnace 100 in the working state is roughly parallel to the direction of gravity). A heat insulation mechanism 300 is disposed between the second heat source 220 and the first heat source 210 and the third heat source 230, and separates the second heat source 220 from the first heat source 210 and the third heat source 230. The spaces corresponding to the growth chamber 110 and the first heat source 210, the second heat source 220, and the third heat source 230 respectively form a first temperature zone 111, a second temperature zone 112, and a third temperature zone 113. The first temperature zone 111 has a first temperature T1, the second temperature zone 112 has a second temperature T2, and the third temperature zone 113 has a third temperature T3, where T1<T2>T3. The rotating lifting frame 400, the first growth container 510, and the plurality of second growth containers 520 are all arranged in the growth chamber 110. The growth material supply mechanism is connected to the growth furnace 100 and is used to input the growth material into the growth chamber 110. The growth material includes liquid growth material and vapor growth material. The first growth container 510 is used to accommodate the seed crystal A and the liquid growth material. The second growth container 520 is used to accommodate the seed crystal A and can accommodate a small amount of liquid growth material. The bottom area of ​​the first growth container 510 is located in the third temperature zone 113 and the top area is located in the second temperature zone 112. The temperature difference between the second temperature zone 112 and the third temperature zone 113 can promote the convection of the liquid growth material in the first growth container 510 in the depth direction. The rotating lifting frame 400 is located in the first temperature zone 113 and the top area is located in the second temperature zone 112. The temperature difference between the second temperature zone 112 and the third temperature zone 113 can promote the convection of the liquid growth material in the first growth container 510 in the depth direction. The temperature zone 111 and the second temperature zone 112, and multiple second growth containers 520 are arranged on the rotating lifting frame 400. The second growth containers 520 can rotate around the rotation center of the rotating lifting frame 400 under the drive of the rotating lifting frame 400, and repeatedly transfer between the first temperature zone 111 and the second temperature zone 112, and repeatedly immerse in the liquid growth material in the first growth container 510. The second growth container 520 always maintains a fixed posture during the rotation process. The fixed posture means that the opening at the top always remains upward in the direction of gravity. The first growth container 510 and the seed crystal A and liquid growth material located in the first growth container 510, the second growth container 520 and the seed crystal A and liquid growth material located in the second growth container 520 respectively form independent crystal growth systems.

[0033] It should be noted that the liquid-phase growth feedstock is in a molten state and includes a molten metal, a nitrogen source, and additives. As known to those skilled in the art, the liquid-phase growth feedstock required for flux-based liquid-phase epitaxial growth of gallium nitride single crystals includes fluxes such as metallic gallium and metallic sodium, and optional additives such as carbon. The specific composition of the liquid-phase growth feedstock is not a target for improvement in the present invention and is therefore not specifically described. It can adopt a ratio and composition known in the art. The vapor-phase growth feedstock can be nitrogen or ammonia, for example. Furthermore, it should be emphasized that the improvement in the present invention primarily addresses the main growth stage suitable for mass production of gallium nitride crystals using the flux method.

[0034] Of course, the growth device also includes other functional mechanisms that are necessary and unnecessary to support the flux-based liquid phase epitaxial growth of gallium nitride single crystals, such as functional mechanisms for maintaining high temperature and high pressure in the growth chamber 110. These are all known to those skilled in the art and are not the direction of improvement of the present invention, so no specific limitations or explanations are given.

[0035] Specifically, the growth furnace 100 can employ structures known in the art. To enhance the stability of the temperature environment required for growth within the growth chamber 110, the inner wall surface of the growth chamber 110 can be provided with an insulation structure. The specific structure and equipment model of the growth furnace 100 are not limited herein. The aforementioned closed structure of the growth chamber 110 means that the growth chamber 110 can remain sealed during operation. The growth furnace 100 is of course provided with a furnace door for the entry and exit of the seed crystal A and the growth container. This is common knowledge among those skilled in the art and will not be elaborated upon here.

[0036] Specifically, the first heat source 210, the second heat source 220, the third heat source 230, and the thermal insulation mechanism 300 are all annular structures arranged along the circumference of the growth chamber 110. The first heat source 210, the second heat source 220, and the third heat source 230 can be conventional electric heating mechanisms or other heating mechanisms. The thermal insulation mechanism 300 can be made of organic or inorganic thermal insulation materials known in the art, such as ceramic fiber materials. The radial widths of the first heat source 210, the second heat source 220, the third heat source 230, and the thermal insulation mechanism 300 can be the same. It should be noted that the first temperature zone 111, the second temperature zone 112, and the third temperature zone 113 can be the spaces enclosed by the first heat source 210, the second heat source 220, and the third heat source 230, respectively. The axial height of the thermal insulation mechanism 300 is less than the axial height of the first growth container 510, and the specific height is not specifically limited. The axial heights of the first temperature zone 111, the second temperature zone 112, and the third temperature zone 113 only need to be able to completely accommodate the first growth container 510, and the second temperature zone 112 and the first temperature zone 111 can be used to accommodate the rotating lifting rack 400, multiple second growth containers 520, and the rotation of multiple second growth containers 520. No specific volume values ​​are limited here.

[0037] Specifically, the volume of first growth container 510 is also greater than the volume of second growth container 520. Specifically, the diameter and height of first growth container 510 are respectively greater than the diameter and height of second growth container 520. Similarly, the area of ​​seed crystal A held in first growth container 510 is also greater than the area of ​​seed crystal A held in second growth container 520. That is, the size of the gallium nitride single crystal grown by the growth system composed of first growth container 510 is greater than the size of the gallium nitride single crystal grown by the growth system composed of second growth container 520. Exemplarily, first growth container 510 and second growth container 520 may be crucibles, etc. The volumes of multiple second growth containers 520 may be the same or different. By using second growth containers 520 of different sizes and multiple seed crystals A of different sizes, gallium nitride single crystals of a wider range of sizes can be grown in batches.

[0038] Specifically, the rotating lifting frame 400 includes a rotating shaft 410 and a plurality of rotating arms 420. The rotating arms 420 are fixedly connected to the rotating shaft 410 and are radially distributed about the rotating shaft 410. The axial direction of the rotating shaft 410 is parallel to the radial direction of the growth chamber 110. The rotating shaft 410 is rotatably coupled to the growth furnace 100. The second growth container 520 is rotatably connected to the rotating arms 420, specifically via a hinge 430. The rotating lifting frame 400 is capable of rotating about the rotating shaft 410. It is understood that the rotation of the rotating lifting frame 400 can be driven by an external power source such as a drive motor through a transmission structure, such as a gear transmission structure. The specific structure of the transmission structure is not limited herein. Specifically, the second growth container 520 and the rotating arms 420 can be connected via a hinge or pivot connection. As a typical implementation scheme, the rotating lifting frame 400 is driven by gears, which makes it convenient for an external power source to provide stable power for rotation and also facilitates the control of the rotation speed. The rotating lifting frame 400 is driven and rotated via gear meshing, so that it rotates clockwise or counterclockwise around the central support position, and the second growth container 520 also rotates clockwise with the rotating lifting frame 400. The rotating lifting frame 400 and the second growth container 520 are connected by a hinge, so that during the rotation process, the second growth container 520 always keeps its opening vertically upward, so that small-sized crystals can grow stably.

[0039] In a more specific embodiment, the process of growing a single crystal by liquid phase epitaxy using the growth apparatus suitable for mass production of crystals by the flux method / liquid phase method specifically includes: A large seed crystal A is placed in a first growth container 510, and smaller seed crystals A are placed in multiple second growth containers 520 (the sizes of the multiple smaller seed crystals A can be the same or different, and the number and arrangement of the seed crystals A in the first growth container 510 and the second growth container 520 are not limited). The seed crystal A is 2-8 inches in size. A metal melt, such as gallium-sodium, is placed in the first growth container 510. The growth chamber 110 is sealed, and the temperature of the first temperature zone 111 is maintained at a first temperature T1, the temperature of the second temperature zone 112 is maintained at a second temperature T2, and the temperature of the third temperature zone 113 is maintained at a third temperature T3, where T1<T2>T3, the first temperature T1, the second temperature T2, and the third temperature T3 are ∈ (700°C-1000°C), and / or the first temperature T1, the second temperature T2, and the third temperature T3 are ∈ (700°C-850°C), the pressure in the growth chamber 110 is adjusted to a pressure required for growing a gallium nitride single crystal, and a nitrogen source is introduced into the growth chamber 110; Drive the rotating lifting frame 400 to rotate, taking one of the second growth containers 520 as an example, Figure 4As shown, the second growth container 520 containing the small-sized seed crystal A enters the second temperature zone 112 from the first temperature zone 111 and is immersed in the metal melt in the first growth container 510 to grow the gallium nitride single crystal. After a certain period of time, as the rotating lifting frame 400 rotates, the second growth container (together with the metal melt, seed crystal A, and grown crystal contained therein) is lifted out of the metal melt, and then enters the first temperature zone 111 from the second temperature zone 112, and is then immersed in the metal melt in the first growth container 510 again. This cycle is repeated multiple times until the growth of the gallium nitride crystal is completed.

[0040] Specifically, by installing three different heat sources within growth chamber 110, separated by thermal insulation 300, three distinct temperature zones are formed, thereby achieving a large internal temperature gradient to promote crystal growth. Specifically, the upper surface temperature of the molten metal in first growth vessel 510 is relatively high (second temperature T2), which facilitates the dissolution of the nitrogen source. After exiting the molten metal, second growth vessel 520 enters first temperature zone 111 (first temperature T1), which has a relatively low temperature. This increases the nitrogen supersaturation in the molten metal in second growth vessel 520, thereby enhancing the crystal growth rate. The bottom of first growth vessel 510 is located in third temperature zone 113, which has a relatively low third temperature T3. The temperature gradient between the upper and lower sides of the molten metal in first growth vessel 510 acts as a driving force for the transport of the nitrogen source, thereby promoting the growth of large crystals within first growth vessel 510.

[0041] Specifically, the second growth container 520 will first be immersed in the molten metal in the first growth container 510 as the rotating lifting frame 400 rotates, and will be pulled out of the molten metal after growing for a period of time. The growth time needs to be determined by testing growth devices of different sizes to determine the optimal rotation speed and corresponding growth time. At this time, there may be defects such as unmerged areas or pits caused by crystal dissolution during the growth process. Therefore, after the second growth container 520 pulls out the molten metal, there will be residual molten metal in the pits, so that the crystal continues to grow, thereby making the defective growth interface further grow into a smoother surface. As the second growth container 520 is repeatedly immersed in and pulled out of the molten metal, the growth quality of the crystal can be effectively improved. At the same time, since the nitrogen source dissolves on the upper surface of the molten metal, in order to effectively transfer it to the bottom of the molten metal, the second growth container 520 rotates under the drive of the rotating lifting frame 400, so that the second growth container 520 can be repeatedly immersed in the molten metal and disturb the molten metal, thereby accelerating the transmission rate of the nitrogen source from the surface of the molten metal to the surface of the seed crystal A, thereby increasing the crystal growth rate.

[0042] It should be noted that during the heating stage of the growth chamber 110, all second growth containers 520 and the seed crystals A therein do not contact the molten metal to avoid the seed crystals A from dissolving back. When the temperature reaches the set value and stabilizes, the second growth containers 520 are driven to rotate and immersed in the molten metal for crystal growth, and repeatedly enter and exit the molten metal to improve the growth quality. After the growth is completed, all small-sized second growth containers 520 are taken out of the molten metal and wait for the crystal to stop growing. At this time, there will not be a large number of poor-quality polycrystals on the surface due to cooling, thereby improving the raw material utilization rate and crystal quality.

[0043] While current flux-based growth methods can only achieve the up-and-down pulling operation during the growth of a single crystal, the present invention enables the simultaneous growth of multiple crystals while ensuring uniform crystal growth. Furthermore, the present invention enables the simultaneous growth of multiple crystals and crystals of varying sizes using a single device. By disturbing the molten metal during the growth vessel's rotation, nitrogen source from the upper surface of the molten metal is effectively transferred to the seed crystal A at the bottom of the molten metal, improving the growth rate and quality of large-sized crystals, increasing crystal yield and yield, and contributing to accelerated industrial development.

[0044] Example 2 See also Figure 5 In this embodiment, the structure of a growth device suitable for mass production of crystals using a flux method / liquid phase method is basically the same as that in Example 1. The identical parts between the two will not be described here. The difference is that: the growth device in this embodiment also includes an in-situ monitoring mechanism (also referred to as an in-situ monitoring system, the same below) 600 and a control mechanism. The in-situ monitoring mechanism 600 is arranged outside the growth chamber 110 and is used to obtain the growth thickness distribution and surface defect distribution of the crystal surface grown in the second growth container 520. The control mechanism is connected to the in-situ monitoring mechanism, the rotating lifting frame 400, the first heat source 210, the second heat source 220, the third heat source 230, and the growth material supply mechanism, and is used to adjust at least one of the rotation speed of the rotating lifting frame 400, the temperature field distribution in the growth chamber 110, and the concentration of the vapor phase growth material in the growth chamber 110. Specifically, the in-situ monitoring mechanism 600 and the control mechanism can be integrated.

[0045] Specifically, a high-temperature optical window is provided on the side of the growth furnace 100. An in-situ monitoring mechanism monitors the crystal in the second growth container 520 located in the growth chamber 110 through the high-temperature optical window. Specifically, the in-situ monitoring mechanism 600 is a structured light full-field scanner. When the second growth container 520 and the crystal growth system it comprises move to a designated position corresponding to the high-temperature optical window, a specific geometric pattern (such as sinusoidal stripes or Gray code) is projected onto the crystal surface using structured light projection technology. The specific geometric pattern deforms due to changes in the crystal surface height. A binocular camera or a monocular camera is used to capture the deformed pattern through multi-angle photography. The three-dimensional coordinates (X / Y / Z) of each pixel are calculated based on the principle of triangulation. Ultimately, the crystal thickness is calculated based on the height difference between the upper and lower surfaces, generating a full-field thickness distribution cloud map. Because liquid-phase gallium nitride crystal growth occurs in a high-temperature, high-pressure environment, and the melt is highly corrosive, high cleanliness requirements are placed on the internal growth environment. Therefore, the in-situ monitoring and control mechanisms are configured as an automated detection system. Combined with high-speed scanning, this system tracks thickness changes during crystal growth in real time, obtaining the growth thickness distribution, surface uniformity, and surface defect distribution of the crystal surface. Specifically, an anti-reflective coating is applied to the exterior of the high-temperature optical window to eliminate interference from specular reflections. A structured light full-field scanner is installed at the in-situ monitor position. By installing the in-situ monitoring mechanism outside the growth chamber 110 and enabling in-situ measurement through a vacuum-sealed interface, contamination of the growth environment is avoided.

[0046] Specifically, by pre-measuring and obtaining the crystal growth rate, crystal morphology, and quality obtained under different growth conditions, numerical calculations are used to obtain the temperature field distribution and nitrogen source concentration distribution results within the metal melt corresponding to each growth condition, thereby establishing a relatively comprehensive growth database and control strategy. When uneven crystal growth thickness is detected, the growth results are quickly matched with the database based on the experience of the growth database and combined with artificial intelligence algorithms. The corresponding possible growth environment and control scheme are displayed on the computer interface. The temperature field distribution, component distribution, flow conditions, etc. within the melt are inferred based on the measurement results, and the current growth parameters, such as temperature, pressure, and rotation rate, are then adjusted to promote the crystal to grow into a smoother surface after entering the melt, avoid warping and cracking caused by uneven stress, and facilitate the production of thicker gallium nitride bulk single crystals. For example, if a crack is detected in the crystal, the rotation rate can be adjusted to quickly skip the crystal, thereby reducing the time and material waste due to ineffective growth. It should be noted that the control mechanism, its circuit structure, data processing system, etc. are all known in the art, and the specific data processing process and logic are not limited here.

[0047] The embodiments of the present invention can combine numerical simulation and artificial intelligence to obtain crystal growth conditions under different states. Based on the measured growth data, the overall situation of the current internal growth environment can be inferred, so that the growth process can be visualized, thereby growing high-quality gallium nitride single crystals.

[0048] The present invention provides a growth device suitable for mass production of crystals using the flux / liquid phase method. This device can monitor the crystal growth process in situ, without affecting the crystal growth environment, to determine the crystal's thickness, uniformity, growth rate, and the presence of defects such as cracks. Furthermore, combined with the rapid matching capabilities of artificial intelligence, the device can reverse-solve the growth results to determine the current growth environment within the melt, which can be displayed on a computer in the form of a graphical interface, making the growth process more clearly controllable.

[0049] The embodiment of the present invention provides a growth device suitable for the flux method / liquid phase method of batch production of crystals. The growth parameters can be adjusted in real time according to the actual growth conditions. The growth conditions of each crystal are different, but they can be monitored one by one, effectively improving the growth quality of each crystal, and improving the controllability and repeatability of the crystal growth process, thereby increasing crystal yield.

[0050] It should be understood that the above embodiments are merely illustrative of the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent variations or modifications made in accordance with the spirit and substance of the present invention are intended to be encompassed within the scope of protection of the present invention.

Claims

1. A growth device suitable for mass production of crystals by flux method / liquid phase method, characterized in that: include: A growth chamber, wherein the growth chamber has a first temperature zone, a second temperature zone, and a third temperature zone arranged in sequence from top to bottom along the growth chamber, wherein the first temperature zone has a first temperature T1, the second temperature zone has a second temperature T2, and the third temperature zone has a third temperature T3, where T1<T2>T3; a first growth container with an open top, disposed within the growth chamber, the first growth container being configured to accommodate seed crystals and liquid-phase growth materials, wherein a bottom region of the first growth container is located in the third temperature zone, and a top region of the first growth container is located in the second temperature zone, wherein a temperature difference between the second temperature zone and the third temperature zone can promote convection of the liquid-phase growth materials within the first growth container in a depth direction; A rotating lifting frame and a plurality of second growth containers with open tops are arranged in the growth chamber, and a plurality of second growth containers are arranged on the rotating lifting frame. The second growth containers are used to accommodate seed crystals and liquid-phase growth materials. The rotating lifting frame is used to drive the second growth containers to rotate around its own rotation center, and the second growth containers always maintain a fixed posture during the rotation process, wherein the rotation trajectory of the second growth container is located in the first temperature zone and the second temperature zone, and the size of the second growth container is smaller than that of the first growth container, and the first growth container is located on the rotation trajectory of the second growth container. The second growth container can be repeatedly immersed in the liquid-phase growth material of the first growth container during the rotation process, and while the liquid-phase growth material in the first growth container enters the second growth container, the liquid-phase growth material in the first growth container is disturbed. The first growth container and the seed crystal and liquid-phase growth material located in the first growth container, and the second growth container and the seed crystal and liquid-phase growth material located in the second growth container respectively form independent crystal growth systems.

2. The growth device suitable for mass production of crystals by flux method / liquid phase method according to claim 1, characterized in that: include: A growth furnace, a first heat source, a second heat source, a third heat source, and a thermal insulation mechanism, wherein the growth furnace has a closed growth chamber therein, the first heat source, the second heat source, and the third heat source being sequentially spaced apart from each other along the axial direction of the growth chamber from top to bottom on the inner wall of the growth chamber, the thermal insulation mechanism being disposed between the second heat source and the first heat source and the third heat source, and isolating the second heat source from the first heat source and the third heat source, and the spaces corresponding to the growth chamber and the first heat source, the second heat source, and the third heat source forming the first temperature zone, the second temperature zone, and the third temperature zone, respectively; And / or, the growth device suitable for flux method / liquid phase method batch production of crystals also includes a growth material supply mechanism, which is used to provide liquid phase growth material to the first growth container and provide vapor phase growth material to the growth chamber.

3. The crystal growth device suitable for flux / liquid phase batch production according to claim 2, characterized in that: The first heat source, the second heat source, the third heat source, and the heat insulation mechanism are all annular structures arranged along the circumference of the growth chamber; and / or, the plurality of second growth containers have the same or different sizes, wherein the sizes include volumes; And / or, the inner wall surface of the growth chamber is a heat-insulating structure.

4. The crystal growth device suitable for flux / liquid phase batch production according to claim 2, characterized in that: The rotating lifting frame includes a rotating shaft and a plurality of rotating arms, wherein the rotating arms are fixedly connected to the rotating shaft, the plurality of rotating arms are radially distributed with the rotating shaft as the center, the second growth container is rotatably connected to the rotating arms, and the rotating lifting frame can rotate around the rotating shaft; and / or, the second growth container is connected to the rotary arm via a hinge or pivot connection; And / or, the axial direction of the rotation axis is parallel to the radial direction of the growth chamber.

5. The growth device suitable for mass production of crystals by flux method / liquid phase method according to claim 2, characterized in that: Also includes: an in-situ monitoring mechanism and a control mechanism, wherein the in-situ monitoring mechanism is disposed outside the growth chamber and is used to obtain a growth thickness distribution and a surface defect distribution of the crystal surface grown in the second growth container; and the control mechanism is connected to the in-situ monitoring mechanism, the rotary lifting frame, the first heat source, the second heat source, the third heat source, and the growth material supply mechanism, and is used to adjust at least one of the rotation speed of the rotary lifting frame, the temperature field distribution in the growth chamber, and the concentration of the vapor phase growth material in the growth chamber; And / or, the growth furnace is provided with a high-temperature resistant optical window, and the in-situ monitoring mechanism includes a structured light full-field scanner, which scans the crystal growing in the second growth container through the high-temperature resistant optical window and obtains the growth thickness distribution, surface uniformity and surface defect distribution of the crystal surface.

6. A method for growing crystals in batches using a flux method or a liquid phase method, characterized in that: include: Provide a growth device suitable for mass production of crystals by flux method / liquid phase method as described in any one of claims 1 to 5; placing a seed crystal and a liquid growth material in the first growth container, placing a seed crystal in the second growth container, maintaining the temperature of the first temperature zone at a first temperature T1, the temperature of the second temperature zone at a second temperature T2, and the temperature of the third temperature zone at a third temperature T3, where T1 < T2 > T3, and providing other growth conditions required for crystal growth in the growth chamber; The rotating lifting frame is rotated to drive the second growth container and the seed crystal carried by it to rotate along the selected rotation trajectory, so that the second growth container and the seed crystal carried by it are repeatedly transferred between the first temperature zone and the second temperature zone, and repeatedly immersed in the liquid-phase growth raw material in the first growth container. At the same time, the liquid-phase growth raw material in the first growth container is disturbed by the repeatedly immersed second growth container, and crystals are grown on the surfaces of the seed crystals in the first growth container and the second growth container by the flux method / liquid phase method.

7. The method for mass production of crystal growth by flux method / liquid phase method according to claim 6, characterized in that: The first temperature T1, the second temperature T2, and the third temperature T3∈(700°C~1000°C).

8. The method for mass production of crystal growth by flux method / liquid phase method according to claim 6 or 7, characterized in that: include: The growth conditions in the growth chamber are adjusted to change at least one of the growth thickness distribution and surface defects of the crystal to grow a crystal with uniform thickness distribution and no defects. The growth conditions include the temperature field distribution in the growth chamber, the pressure in the growth chamber, the concentration of the vapor phase growth raw material in the growth chamber, and the residence time of the second growth container and the seed crystal carried by the second growth container in the liquid phase growth raw material in the first growth container.

9. The method for mass production of crystal growth by flux method / liquid phase method according to claim 8, characterized in that: Specifically include: Measuring and obtaining a growth thickness distribution cloud map of the crystal, and adjusting the growth conditions in the growth chamber according to the growth thickness distribution cloud map to grow a crystal with uniform thickness distribution and no defects; And / or, the growth method specifically includes: A growth database is constructed to show the corresponding relationship between crystal growth conditions and crystal growth rate, morphology and quality, and the growth conditions are adjusted according to the growth thickness distribution data of the crystal obtained by actual measurement.

10. The method for mass production of crystal growth by flux method / liquid phase method according to claim 6, characterized in that: The size of the seed crystal in the first growth container is larger than the size of the seed crystal in the second growth container; And / or, the seed crystals in the plurality of second growth containers have the same or different sizes.

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