Gallium oxide crystal growth device and method

Abstract

The invention discloses a gallium oxide crystal growth device and method, and relates to the field of crystal manufacturing. The gallium oxide crystal growth device comprises a closed cavity, and a temperature gradient with the temperature gradually reduced from top to bottom can be formed in the closed cavity; the supporting device is arranged at the bottom of the closed cavity in a penetrating manner; the growth assembly is located in the closed cavity and used for gallium oxide crystal growth, and the growth assembly is arranged on the supporting device and can move up and down; the weighing device is arranged at the bottom of the supporting device and can weigh the growth assembly; the feeding device is arranged at the top of the closed cavity in a penetrating mode, a discharging port of the feeding device is located over the growth assembly, and raw materials can be added into the growth assembly. According to the gallium oxide crystal growth device and method, on the premise of ensuring the yield of gallium oxide crystals, the crucible is prevented from being damaged, and the use cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of crystal manufacturing, and in particular to a gallium oxide crystal growth device and method. Background Art

[0002] As the core technology for gallium oxide crystal growth, the Vertical Bridgman Method (VB) has made significant progress in recent years in breaking through the limitations of the traditional guided mode method (EFG) that relies on precious metal iridium crucibles.

[0003] Currently, the mainstream vertical Bridgman method for growing gallium oxide uses a mechanical method to slowly lower a crucible from a high-temperature zone to a low-temperature crystallization zone below the furnace. During this process, the crystals grow from bottom to top. Because the growth furnace needs to be sealed, the existing vertical Bridgman method uses a one-time feeding method before crystal growth. Raw materials cannot be replenished during crystal growth. Therefore, to increase the yield of gallium oxide crystals, the existing method is to increase the one-time charging amount. However, loading a sufficient amount of gallium oxide raw material at one time or using an uncontrolled one-time feeding method will cause the melt height to be too high, generating greater pressure, forcing excessive deformation on the crucible wall, which can easily lead to crucible damage. Moreover, when the gallium oxide melt height is too high, oxygen deficiency at the bottom of the melt causes the gallium oxide to decompose into gallium, which easily corrodes the crucible and may cause the crucible to leak. Even if leakage does not occur, it will increase crucible wear and tear, increasing the cost of use.

[0004] Therefore, it is urgent to design a technical solution that can ensure the output of gallium oxide crystals while avoiding crucible breakage and reducing the cost of use. Summary of the Invention

[0005] The purpose of the present invention is to provide a gallium oxide crystal growth device and method to solve the problems existing in the above-mentioned prior art, and to avoid crucible damage and reduce the cost of use while ensuring the output of gallium oxide crystals.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a gallium oxide crystal growth device, comprising:

[0008] A closed cavity can form a temperature gradient inside which the temperature gradually decreases from top to bottom;

[0009] A supporting device is provided on the bottom of the sealed cavity;

[0010] A growth assembly, located in the sealed chamber and used for growing gallium oxide crystals, wherein the growth assembly is provided on the support device and is capable of moving up and down;

[0011] a weighing device, disposed at the bottom of the support device, capable of weighing the growing assembly;

[0012] A feeding device is provided on the top of the closed cavity, and its discharge port is located just above the growth component, and can add raw materials into the growth component.

[0013] Preferably, the feeding device includes a feeding pipe vertically passing through the top of the closed cavity, the bottom of the feeding pipe is connected to a curved pipe, and the opening of the curved pipe away from one end of the feeding pipe forms the discharge port.

[0014] Preferably, the feeding tube and the curved tube are integrally formed; the curved tube is an S-shaped structure, and the curved tube is arranged vertically downward away from the opening at one end of the feeding tube.

[0015] Preferably, a heat-insulating layer is provided on the side wall of the sealed cavity; a heating element is passed through the top of the sealed cavity, and the heating end of the heating element is located at an upper position inside the sealed cavity.

[0016] Preferably, a plurality of the heating elements are provided on the top of the sealed cavity, and the plurality of heating elements are circumferentially arranged outside the feeding pipe.

[0017] Preferably, the growth assembly includes a crucible with an open top, the crucible is slidably arranged on the support device, a driving assembly is installed on the support device, and the driving assembly can drive the crucible to move up and down along the support device; a seed crystal is penetrated through the bottom of the crucible.

[0018] Preferably, the growth assembly includes a crucible with an open top, the crucible is fixed to the top of the support device, the bottom of the support device is connected to a driving assembly, and the driving assembly can drive the support device to move up and down in the closed cavity; a seed crystal is passed through the bottom of the crucible.

[0019] Preferably, a temperature measuring device is provided at a position of the crucible close to the seed crystal, and the temperature measuring device is electrically connected to a display, which is located outside the closed cavity and can display the temperature value measured by the temperature measuring device.

[0020] Preferably, the feeding tube is movable up and down along its position passing through the closed cavity.

[0021] The present invention also provides a gallium oxide crystal growth method, comprising the following steps:

[0022] Add a set amount of raw materials into the crucible, and then place the crucible on a support device in a closed cavity;

[0023] Starting the heating element and detecting the temperature value by the temperature measuring device; when the temperature value is at the point where the raw material in the crucible is melted and the seed crystal is not melted, calculating the remaining space in the crucible according to the value of the weighing device, and adding the raw material into the crucible by the feeding device;

[0024] After the gallium oxide melt level in the crucible reaches a preset height, the crucible is moved downward to grow a single crystal. The feeding device descends synchronously with the crucible and continues to feed until the total weight of the added raw materials equals the weight of the crystal at the seed crystal when it has grown to its limit. Then, the feeding is stopped.

[0025] After all the remaining raw materials in the crucible have completed their growth, the crucible stops moving downward and the feeding device is lifted upward.

[0026] Compared with the prior art, the present invention has achieved the following technical effects:

[0027] The present invention provides a feeding device at the top of the sealed chamber, with the discharge port of the feeding device positioned above the crucible, enabling continuous feeding. Combined with data feedback from a weighing device at the bottom, a small amount of raw material can be initially added to the crucible, and raw material can be continuously added during the crystal growth process. The addition of raw material is stopped when the total weight of the added raw material and the initially added raw material equals the total weight of raw material required for the crystal at the seed crystal to grow to its limit. Compared to the prior art, which can only add a small amount of raw material at a time, the present invention achieves full utilization of the crucible's equal diameter and height. Compared to the prior art, the growth furnace structure provided by the present invention can achieve continuous feeding while maintaining a substantially unchanged growth environment, maximizing crucible utilization, obtaining crystals of larger size and greater effective height, and increasing the yield of gallium oxide single crystals. This solves the problems of low crucible utilization and low yield of single crystals of effective size used in the traditional VB method for growing gallium oxide, thereby reducing the cost of growing gallium oxide single crystals.

[0028] Specifically, the present invention uses an initial small amount of gallium oxide raw material to be added to the crucible to obtain a lower liquid level height, increase the oxygen content at the bottom of the melt, inhibit the decomposition of gallium oxide, and thus reduce the erosion of the crucible. It alleviates the problem of excessive raw material added to the crucible at one time, forming a deeper melt, resulting in oxygen deficiency at the bottom of the melt, and causing gallium oxide decomposition to corrode the crucible. It reduces the risk of crucible leakage and the cost of using the crucible. The present invention uses an initial small amount of material to avoid crucible leakage caused by excessive deformation of the crucible wall due to excessive melt height, thereby ensuring the safety of the crystal growth process. During the crystal growth process, the thermal field stability directly determines the quality of the crystal, and the stable solid-liquid interface position and shape are the key to thermal field stability. The present invention uses a feeding device to continuously feed the crucible during the crystal growth process, controls the melt in the crucible to always remain at a height, ensures that the growth interface of the crystal always remains slightly convex, achieves thermal field stability, and guarantees crystal growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Schematic diagram of the principle of a gallium oxide crystal growth device in one or some embodiments of the present invention.

[0031] In the figure: 1-feeding device; 2-gallium oxide particles; 3-heating element; 4-insulation layer; 5-crucible; 6-weighing device; 7-support device; 8-seed crystal; 9-gallium oxide melt; 10-temperature measuring device. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] The purpose of the present invention is to provide a gallium oxide crystal growth device and method to solve the problems existing in the above-mentioned prior art, and to avoid crucible damage and reduce the cost of use while ensuring the output of gallium oxide crystals.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] The present invention mainly relates to an improvement in a scheme for growing gallium oxide crystals using a vertical Bridgman method. When growing gallium oxide crystals using the vertical Bridgman method, raw materials need to be added to a crucible, which is then placed in a sealed growth furnace to achieve growth of the gallium oxide crystals through a temperature gradient. The raw materials are generally gallium oxide particles or gallium oxide blocks. In conventional gallium oxide crystal growth schemes, the gallium oxide particles or gallium oxide blocks need to be placed in a crucible at one time, which is then placed in a sealed growth furnace to melt the raw materials at a high temperature, and the melted raw materials are used to grow gallium oxide crystals. To ensure a constant growth environment, the growth furnace cannot be opened midway after the raw materials are added once. Due to the large density difference between the gallium oxide blocks and the gallium oxide crystals, the volume of the gallium oxide blocks is larger than the volume of the gallium oxide crystals of equal weight. Therefore, after adding the raw materials to a set height in the crucible at one time, the size of the gallium oxide crystals that can be grown is limited, resulting in low crucible utilization and a low yield of single crystals of an effective size, resulting in high crystal growth costs.

[0036] In order to obtain a higher single-time gallium oxide crystal output, it is necessary to continuously increase the crucible's equal diameter height and the growth furnace's hearth height to increase the crucible's depth, and then add more raw materials into the crucible. However, this approach will greatly increase the cost and risk of crystal growth. Filling a sufficient amount of gallium oxide raw materials at one time or an uncontrolled one-time feeding method will make the melt height in the crucible too large, generating greater pressure, forcing the crucible wall to form an excessive deformation, which can easily lead to crucible damage. Moreover, if the gallium oxide melt height is too large, the lack of oxygen at the bottom of the melt will cause gallium oxide to decompose into gallium elemental matter, which can easily corrode the crucible. The crucible may therefore leak. Even if no leakage occurs, the crucible loss will increase, thereby increasing the cost of use. In order to solve this problem, the present invention provides a gallium oxide crystal growth device suitable for growing gallium oxide crystals by the vertical Bridgman method. See attached. Figure 1 As shown, the device includes a closed cavity, inside which a temperature gradient can be formed with the temperature gradually decreasing from top to bottom. The closed cavity is equivalent to a growth furnace; a support device 7 is provided at the bottom of the closed cavity; a growth component is located in the closed cavity and is used for growing gallium oxide crystals. The growth component is provided on the support device 7 and can move up and down; a weighing device 6 is provided at the bottom of the support device 7 and can weigh the growth component; a feeding device 1 is provided at the top of the closed cavity, and its discharge port is located directly above the growth component, and can add raw materials to the growth component.

[0037] The present invention utilizes an initial small amount of gallium oxide raw material to achieve a lower liquid level, increase the oxygen content at the bottom of the melt, inhibit the decomposition of gallium oxide, and thereby reduce corrosion of the crucible 5. This alleviates the problem of excessive addition of raw material to the crucible 5 at once, resulting in a deeper melt and oxygen deficiency at the bottom of the melt, which in turn leads to corrosion of the crucible 5 by gallium oxide decomposition. This reduces the risk of crucible 5 leakage and the cost of using the crucible 5. The present invention utilizes a small initial amount of material to avoid leakage caused by excessive deformation of the crucible 5 caused by excessive melt height, thereby ensuring the safety of the crystal growth process. During crystal growth, thermal field stability directly determines crystal quality, and a stable solid-liquid interface position and shape are key to thermal field stability. The present invention utilizes a feeding device 1 to continuously feed material into the crucible 5 during crystal growth, controlling the melt in the crucible 5 to maintain a constant height, ensuring that the crystal growth interface remains slightly convex, achieving thermal field stability, and guaranteeing crystal growth. The furnace structure of the device of the present invention can realize continuous feeding while maintaining the growth environment basically unchanged. During the crystal growth process, the melt in the crucible 5 gradually decreases. At this time, continuous replenishment of materials is performed to replenish the reduced melt in the crucible 5, so that the gallium oxide crystals can continue to grow, and the melt level in the crucible 5 will not be too high, but always be below the set safety liquid level, thereby maximizing the utilization rate of the crucible 5, obtaining crystals of larger size and larger effective height, and improving the yield of gallium oxide single crystals.

[0038] To maintain the growth environment within the sealed chamber as unchanged as possible and prevent it from being disrupted during the feeding process, in one embodiment, the feeding device 1 is designed as a feeding tube vertically extending through the top of the sealed chamber. The feeding tube is made of a 30-40 wt% Pt-Rh alloy, a binary alloy primarily composed of platinum (Pt) and rhodium (Rh). "Wt%" means "weight percentage" or "mass fraction," representing the proportion of a component's mass to the total mass of a mixture. In the present invention, the weight percentage of the Pt-Rh alloy in the feeding tube is 30-40%. The crucible 5 of this embodiment is made of a 10-30 wt% Pt-Rh alloy. The bottom of the feeding tube is connected to a curved tube integrally formed with the feeding tube. The opening at one end of the curved tube, away from the feeding tube, forms a discharge port. The curved tube has an S-shaped structure, resembling two U-shaped tubes butted together, with the opening at the other end of the curved tube extending vertically downward. The present invention designs the bottom of the feeding tube as a curved tube structure, and gallium oxide particles can be added to the feeding tube from the outside of the closed cavity. The gallium oxide particles accumulate at the curved tube, and because the curved tube is located at the upper part of the closed cavity and is at a position with a higher temperature gradient, the gallium oxide particles accumulated at the curved tube are heated and turned into gallium oxide melt 9, thereby achieving a sealing effect on the feeding tube, preventing the closed cavity from communicating with the outside through the feeding tube, and ensuring that the growth environment in the closed cavity remains unchanged; when the crucible 5 needs to be supplemented with material, gallium oxide particles are continuously added to the feeding tube from the outside, and the gallium oxide melt is heated. The particles squeeze the melt within the curved tube. Specifically, when gallium oxide melt 9 accumulates to a certain level within the curved tube, the newly added gallium oxide particles, squeezed by the pressure differential, enter the U-shaped structure at the upper portion of the curved tube and flow toward the discharge port, from which they fall into the crucible 5. By calculating the liquid level of the gallium oxide melt 9 formed by the melted gallium oxide material within the U-shaped tube, real-time control of the amount of gallium oxide melt 9 added to the crucible 5 is achieved. This ensures that gallium oxide melt 9 is always present in the lower U-shaped tube structure, sealing the feed tube and preventing disruption to the growth environment within the sealed cavity. This allows for continuous growth while maintaining a substantially unchanged growth environment, resulting in larger crystals and increased yield. Furthermore, it effectively reduces wear and tear on the crucible 5.

[0039] In order to form the required temperature gradient, in one embodiment, an insulation layer 4 is provided on the side wall of the closed cavity; a heating element 3 is provided on the top of the closed cavity, and the heating end of the heating element 3 is located at the upper position inside the closed cavity. The insulation layer 4 of this embodiment is made of two layers of insulation bricks, the inner insulation brick is zirconia fiber brick, and the outer insulation brick is alumina fiber brick. The closed space surrounded by the two layers of insulation bricks serves as a crystal growth space; the heating element 3 of this embodiment is a silicon-molybdenum rod, the cold end of the silicon-molybdenum rod is placed in the top insulation layer 4, and the heating end of the silicon-molybdenum rod is suspended in the closed space, and the silicon-molybdenum rod is externally connected to a power supply, which can realize the heating of the closed space inside the closed cavity. Since the heating end of the silicon-molybdenum rod is located in the middle and upper part of the closed space, there will be a temperature difference between the middle and lower part and the middle and upper part of the closed space, thereby forming a temperature gradient. In order to achieve more uniform heating of the raw materials in the crucible 5, in one embodiment, a plurality of heating elements 3 are provided on the top of the closed cavity, and the plurality of heating elements 3 are circumferentially arranged on the outside of the feeding tube and the crucible 5, so as to achieve an all-round heating effect on the crucible 5 and the curved tube of the feeding tube.

[0040] The growth component is a mature existing technical structure, so it will not be described in detail; the growth component of this embodiment includes a crucible 5 with an open top, and a seed crystal 8 is penetrated at the bottom of the crucible 5 for growing gallium oxide crystals; the crucible 5 of this embodiment is slidably arranged on the support device 7 through a slider structure, and a driving component is installed on the support device 7, and the driving component can drive the crucible 5 to move up and down along the support device 7; the driving component of this embodiment can be a cylinder or a hydraulic cylinder arranged on the support device 7, and its cylinder body is vertically fixed on the support device 7, and the end of the cylinder rod is connected to the crucible 5, and the up and down movement of the crucible 5 is achieved by the extension and contraction of the cylinder rod; the driving component can also adopt a screw nut pair, the screw is rotatably connected to the support device 7, and one end of the screw is connected to the screw motor, the nut is arranged on the screw, and the nut is fixedly connected to the crucible 5, and the screw rotates, and the nut can drive the crucible 5 to move up and down along the screw.

[0041] In another embodiment, the crucible 5 is fixed on the top of the support device 7, and the support device 7 adopts a mature support frame or support rod structure. The upper part of the support device 7 has a space that will not interfere with the arrangement of the seed crystal 8 and the growth of the gallium oxide crystal. The lower part of the support device 7 adopts a sealed columnar structure or block structure. The lower part of the support device 7 passes through the bottom of the closed cavity, which can ensure the sealing at the penetration position. The bottom of the support device 7 is connected to a driving component, and the driving component can adopt a cylinder or a screw nut substructure, which can drive the support device 7 to move up and down in the closed cavity, thereby realizing the function of driving the crucible 5 to move up and down synchronously. In this embodiment, a sealing gasket structure is provided at the position where the support device 7 passes through the bottom of the closed cavity. When the support device 7 moves up and down along the penetration position of the bottom of the closed cavity, it can ensure that this position is always in a sealed state, that is, the support device 7 and the bottom of the closed cavity are connected by a sliding seal, which ensures that the growth environment inside the closed cavity will not be destroyed.

[0042] In one embodiment, in order to facilitate the replenishment of raw materials, the feeding tube can move up and down along the position where it passes through the closed cavity. A sealing ring is also provided at the position where the feeding tube passes through the closed cavity to ensure good sealing performance. The outside of the feeding tube is connected to a cylinder, a hydraulic cylinder or a screw nut substructure, which can realize the up and down movement control of the feeding tube. The feeding tube can be manually adjusted to make its movement speed the same as or different from that of the crucible 5, and the specific setting can be based on needs.

[0043] Since the melting temperature of the gallium oxide raw material is lower than the melting temperature of the seed crystal 8, when growing gallium oxide crystals, it is necessary to ensure that the temperature value is in a state where the gallium oxide raw material is melted and the seed crystal 8 is not melted. In order to be able to accurately control this temperature value range, in one embodiment, a temperature measuring device 10 is provided at a position of the crucible 5 near the seed crystal 8. The temperature measuring device 10 adopts a temperature measuring thermocouple. The temperature measuring device 10 is electrically connected to a display. The display is located outside the closed cavity and can display the temperature value measured by the temperature measuring device 10 to ensure that the temperature is between the melting temperature value of the gallium oxide raw material and the melting temperature value of the seed crystal 8.

[0044] The present invention also provides a gallium oxide crystal growth method, comprising the following steps:

[0045] Add a set amount of raw materials into the crucible 5, and then place the crucible 5 on the support device 7 in the closed cavity;

[0046] The heating element 3 is started, and the temperature value is detected by the temperature measuring device 10. When the temperature value is when the raw material in the crucible 5 is melted and the seed crystal 8 is not melted, the remaining space in the crucible 5 is calculated according to the value of the weighing device 6, and the raw material is added through the feeding device 1. The raw material in this embodiment is gallium oxide particles 2; the added gallium oxide particles 2 will melt into gallium oxide melt 9 at the lower U-shaped tube. As the gallium oxide particles 2 in the feeding tube are continuously added, the pressure in the curved tube increases, driving the melt therein to fall into the crucible 5, thereby continuously adding gallium oxide melt 9 to the crucible 5; the weighing device 6 is provided at the bottom of the supporting device 7, which can weigh the supporting device 7, crucible 5 and seed crystal 8 at the same time. Since the weight of the supporting device 7, crucible 5 and seed crystal 8 is fixed, the weight of the supporting device 7, crucible 5 and seed crystal 8 is fixed. The weight of the gallium oxide raw material in the crucible 5 is fixed and unchanged, so the value after subtracting the weight of the supporting device 7, crucible 5 and seed crystal 8 is the weight of the gallium oxide raw material in the crucible 5; the weight of the gallium oxide melt 9 in the crucible 5 when it is added to the maximum value without damaging the crucible 5 is calculated as weight one. When the initial amount of material added to the crucible 5 exceeds weight one, the height of the gallium oxide melt 9 in the crucible 5 is too large, which may cause damage to the crucible 5. The weight one can be calculated by weighing in advance before crystal growth; the present invention initially adds a small amount of raw material to the crucible 5. According to the weight of the added raw material and the internal space size of the crucible 5, the existing calculation method can be used to calculate the difference between the liquid level of the melt in the crucible 5 and the liquid level in the crucible 5 at weight one. This difference is the remaining space in the crucible 5;

[0047] After the liquid level of the gallium oxide melt 9 in the crucible 5 reaches a preset height, which is lower than the liquid level in the crucible 5 at weight one, the crucible 5 is moved downward to grow gallium oxide crystals. The melt in the crucible 5 gradually grows into gallium oxide crystals at the seed crystal 8, and the melt in the crucible 5 gradually decreases. The maximum size of gallium oxide crystals grows at the seed crystal 8, and the weight of the melt in the crucible 5 at this time is zero, which is calculated as weight two. For ease of calculation, weight one and weight two are both values ​​after deducting the weight of the crucible 5, the supporting device 7, and the seed crystal 8. The feeding device 1 descends synchronously with the crucible 5 and continues to feed. A physical reaction occurs during the growth of gallium oxide crystals, and only the volume changes, while the weight does not change. Therefore, during the growth of gallium oxide crystals, the feeding tube continues to add material, and the weight value at the weighing device 6 gradually increases and gradually approaches the weight of two. When the total weight of the added raw materials is equal to the weight value when there is no raw material in the crucible 5 and the crystal at the seed crystal 8 has grown to its limit, the feeding is stopped. At this time, the weight of the remaining raw materials in the crucible 5 and the total weight of the grown crystals are weight two; the remaining raw materials in the crucible 5 continue to grow into crystals, and since no more materials are added, the total weight no longer changes.

[0048] After all the remaining raw materials in the crucible 5 have completed growth, the crucible 5 stops moving downward and the feeding device 1 is lifted to prevent it from staying in the high-temperature area for too long and causing damage. Since the density of gallium oxide crystals is greater than the density of the melt, the crystals have a volume shrinkage relative to the melt. The space of the crucible 5 can be fully utilized by continuously adding materials. At the same time, the VB method can also achieve the growth of gallium oxide single crystals with different crystal planes by adjusting the crystal orientation of the seed crystal 8.

[0049] Since the height of the initial addition of material in the present invention is lower than the height at weight one, the problem caused by the excessive height of the melt in the crucible 5 is avoided. During the subsequent crystal growth process, the melt in the crucible 5 gradually decreases, and the reduced melt in the crucible 5 is replenished by continuously adding material until weight two, at which time it is stopped. At this time, the remaining raw materials in the crucible 5 can continue to grow crystals, so that the crystal size is maximized. Under the premise of not changing the equal diameter height of the crucible 5 and the furnace height, the space of the crucible 5 is fully utilized to achieve efficient growth of large-sized gallium oxide single crystals.

[0050] The present invention uses a small amount of initial feeding to form a melt layer with a low liquid level, increases the oxygen content at the bottom of the melt, inhibits the decomposition of gallium oxide, and further reduces corrosion to the crucible 5, thereby avoiding leakage of the crucible 5 due to corrosion by the melt; the use of a small amount of initial feeding avoids leakage of the crucible 5 caused by excessive deformation of the crucible 5 wall due to excessive melt height, thereby ensuring the safety of the crystal growth process. In the existing VB method for growing gallium oxide crystals, since it is impossible to add more materials, the melt in the crucible is constantly decreasing, and the crystals at the bottom are constantly increasing, resulting in a continuous decrease in the temperature gradient at the solid-liquid interface between the melt and the crystal. The solid-liquid interface will change from a slightly convex interface to a flat interface or even a concave interface, which will lead to a sharp increase in the probability of polycrystals and twins. The present invention continuously adds materials through a feeding tube to control the melt to always remain within a certain height range, thereby ensuring that the growth interface of the crystal always remains in a slightly convex state, avoiding the formation of polycrystals and twins, and improving the quality of the crystal; the curved tube at the bottom of the feeding tube adopts two The crucible 5 is formed by a U-shaped tube structure arranged vertically. Utilizing the operating principle of the U-shaped tube structure, the diameter of the U-shaped tube is known, so the volume of the melt that can be accommodated therein can be calculated. By calculating the liquid level of the gallium oxide melt 9 formed by the melting of the introduced gallium oxide material within the U-shaped tube, the weight of the introduced gallium oxide raw material can be calculated using existing techniques. Based on the tube diameter, the liquid level within the tube, and the melt density, the melt weight can be calculated. The calculation method is existing and will not be described in detail. This enables the feeding tube to control the weight of the gallium oxide melt 9 added to the crucible 5 in real time. For ease of control, a solenoid valve can be provided on the upper portion of the feeding tube to facilitate on / off adjustment of the feeding tube, thereby achieving on / off control of the feeding process.

[0051] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A gallium oxide crystal growth device, characterized in that: include: A closed cavity can form a temperature gradient inside which the temperature gradually decreases from top to bottom; A supporting device is provided on the bottom of the sealed cavity; A growth assembly, located in the sealed chamber and used for growing gallium oxide crystals, wherein the growth assembly is provided on the support device and is capable of moving up and down; a weighing device, disposed at the bottom of the support device, capable of weighing the growing assembly; A feeding device is provided on the top of the closed cavity, and its discharge port is located just above the growth component, and can add raw materials into the growth component.

2. The gallium oxide crystal growth device according to claim 1, wherein: The feeding device includes a feeding pipe vertically passing through the top of the closed cavity, the bottom of the feeding pipe is connected to a curved pipe, and the opening of the curved pipe away from one end of the feeding pipe forms the discharge port.

3. The gallium oxide crystal growth device according to claim 2, wherein: The feeding pipe and the curved pipe are integrally formed; the curved pipe is an S-shaped structure, and the curved pipe is arranged vertically downward away from the opening at one end of the feeding pipe.

4. The gallium oxide crystal growth apparatus according to claim 1, wherein: The side wall of the sealed cavity is provided with a heat-insulating layer; the top of the sealed cavity is penetrated by a heating element, and the heating end of the heating element is located at an upper position inside the sealed cavity.

5. The gallium oxide crystal growth device according to claim 4, wherein: A plurality of heating elements are provided on the top of the sealed cavity, and the plurality of heating elements are circumferentially arranged outside the feeding pipe.

6. The gallium oxide crystal growth device according to claim 1, wherein: The growth assembly includes a crucible with an open top, the crucible is slidably arranged on the support device, a driving assembly is installed on the support device, and the driving assembly can drive the crucible to move up and down along the support device; a seed crystal is passed through the bottom of the crucible.

7. The gallium oxide crystal growth apparatus according to claim 1, wherein: The growth assembly includes a crucible with an open top, which is fixed to the top of the support device. The bottom of the support device is connected to a driving assembly, which can drive the support device to move up and down in the closed cavity; a seed crystal is passed through the bottom of the crucible.

8. The gallium oxide crystal growth device according to claim 6 or 7, characterized in that: A temperature measuring device is provided at a position of the crucible close to the seed crystal. The temperature measuring device is electrically connected to a display. The display is located outside the closed cavity and can display the temperature value measured by the temperature measuring device.

9. The gallium oxide crystal growth device according to claim 2, wherein: The feeding tube can move up and down along its position passing through the closed cavity.

10. A method for growing gallium oxide crystals, characterized in that: The steps include: Add a set amount of raw materials into the crucible, and then place the crucible on a support device in a closed cavity; Starting the heating element and detecting the temperature value by the temperature measuring device; when the temperature value is at the point where the raw material in the crucible is melted and the seed crystal is not melted, calculating the remaining space in the crucible according to the value of the weighing device, and adding the raw material into the crucible by the feeding device; After the gallium oxide melt level in the crucible reaches a preset height, the crucible is moved downward to grow a single crystal. The feeding device descends synchronously with the crucible and continues to feed until the total weight of the added raw materials equals the weight of the crystal at the seed crystal when it has grown to its limit. Then, the feeding is stopped. After all the remaining raw materials in the crucible have completed their growth, the crucible stops moving downward and the feeding device is lifted upward.

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