High-efficiency silicon carbide single crystal growth device

Abstract

The invention relates to the field of silicon carbide crystal growth, in particular to a high-efficiency silicon carbide single crystal growth device which comprises a crucible body, the crucible body is divided into a high-temperature area and a low-temperature area from top to bottom according to temperature area distribution, and the high-temperature area and the low-temperature area are communicated with each other; wherein a powder starter used for containing a silicon carbide powder source is arranged in the high-temperature area, and a carbon powder area used for containing carbon powder is further arranged at the top of the high-temperature area; a seed crystal for depositing a silicon carbide crystal is arranged at the bottom of the low-temperature area in a bonding manner; a filtering device for filtering solid particles falling to the surface of the seed crystal is also arranged in the crucible main body. By changing the setting directions of the high-temperature area and the low-temperature area in the crucible main body, the diffusion direction and the distribution mode of gas for silicon carbide single crystal deposition are effectively changed, so that the crystal growth rate is increased.

Description

Technical Field

[0001] The invention relates to the field of silicon carbide crystal growth, and in particular to a high-efficiency silicon carbide single crystal growth device. Background Art

[0002] Silicon carbide is a typical wide bandgap semiconductor material and is the third generation semiconductor material after silicon and gallium arsenide. Compared with silicon and gallium arsenide, silicon carbide has excellent properties such as high thermal conductivity, high breakdown field strength, and high saturated electron drift rate, and has application prospects in high temperature, high frequency, high power and radiation-resistant devices.

[0003] At present, the common method for preparing silicon carbide single crystals is physical vapor transport (PVT). That is, silicon carbide powder is placed at the bottom of a closed graphite crucible, and a silicon carbide seed crystal is placed at the center of the top of the crucible. For example, a crucible for growing large-sized silicon carbide single crystals with publication number CN213172678U is designed in this way. This type of crucible reasonably designs the thermal field distribution of the single crystal furnace so that the temperature of the powder source area is higher than the temperature of the seed crystal area, and the powder source area reaches the sublimation temperature point of the silicon carbide powder source. Si, C, Si2C, SiC2, SiC and other molecules generated by the sublimation of the silicon carbide powder source are transported to the vicinity of the seed crystal area through diffusion or convection effects. Due to the low temperature in the seed crystal area, the above atmosphere forms a certain degree of supercooling and crystallizes into SiC crystals on the surface of the seed crystal.

[0004] Since the silicon carbide powder source produces non-stoichiometric sublimation at high temperature, the volatilized atmosphere is mainly silicon-rich atmosphere. The powder will gradually become carbon-rich as the growth process proceeds. During the growth of a single crystal, a silicon-enriched atmosphere will accumulate near the growth surface. According to the crystal growth chemical reaction equilibrium equation, the forward reaction process of crystal growth will be inhibited under the condition of a silicon-rich atmosphere near the growth surface. As the growth proceeds, the silicon enrichment effect intensifies. The crystal growth rate gradually decreases. Therefore, the method of increasing the crystal thickness by increasing the growth time is inefficient.

[0005] At present, the thickness of silicon carbide single crystals (8 inches) grown at home and abroad is generally around 2-3cm, which is much lower than the crystal growth length of a single furnace of first-generation semiconductor Si or second-generation semiconductor GaAs materials. The growth rate of SiC crystals is generally 5-10 days / furnace, and the average growth rate is generally not higher than 0.5mm / h. With the development of the SiC industry, in the process of SiC crystal size gradually transitioning from 4 and 6 inches to 8 and 12 inches, the above-mentioned silicon enrichment effect will cause more significant crystal growth inhibition. Therefore, the manufacturing cost and competitiveness of SiC single crystal materials are limited. Summary of the invention

[0006] The present application aims to overcome the defect of low efficiency of the growth device for growing silicon carbide crystals in the prior art in the process of growing large-sized silicon carbide crystals, and provides a high-efficiency silicon carbide single crystal growth device to overcome the above-mentioned shortcomings.

[0007] To achieve the above-mentioned purpose, the present invention is implemented by the following technical solutions: In a first aspect, the present invention first provides a high-efficiency silicon carbide single crystal growth device, It comprises a crucible body, which is divided into a high temperature zone and a low temperature zone from top to bottom according to the temperature zone distribution, and the high temperature zone and the low temperature zone are interconnected; wherein, A powder material area for containing silicon carbide powder source is provided in the high temperature area, and a carbon powder area for containing carbon powder is also provided on the top of the high temperature area; A seed crystal for depositing silicon carbide crystals is bonded to the bottom of the low temperature zone; A filtering device for filtering solid particles falling onto the surface of the seed crystal is also arranged inside the crucible body.

[0008] Generally speaking, the temperature at the bottom of the existing silicon carbide growth device is higher than the temperature at the top, so the gas formed by the silicon carbide powder source after gasification will gradually diffuse upward, thereby crystallizing at the seed crystal at the top to form a silicon carbide single crystal. Compared with the prior art, the present application adopts a completely different thermal field distribution setting. In the present application, the upper part of the crucible body is a high-temperature zone, and the lower part of the crucible body is a low-temperature zone. Therefore, after silicon carbide sublimates in the high-temperature zone, the growth atmosphere generated by its volatilization is gradually transported from the upper end of the crucible body to the seed crystal area at the bottom of the crucible body by diffusion or convection, and forms a supersaturated atmosphere to complete crystal growth.

[0009] The reason for this setting is closely related to the thermal decomposition, volatilization and crystallization of silicon carbide powder source. Many years of theoretical and experimental research on the preparation of SIC crystal materials ("Silicon Carbide Crystal Growth and Defects", Shi Erwei, Science Press) pointed out: The equations for the decomposition reaction of sic powder in the powder area mainly include: The equations for the SIC crystallization reaction in the seed crystal area mainly include: .

[0010] From the above equations and PVT growth theory, it can be seen that the silicon carbide powder area reacts (1)(2)(3), resulting in the volatile gas phase component being rich in Si and residual solid C particles. The above atmosphere crystallizes in the seed crystallization area, and finally obtains SiC crystals with a stoichiometric ratio of 1:1, that is, the residual Si atmosphere is in the gas phase, which leads to the enrichment of silicon atmosphere. From the chemical reaction equation (4), it can be seen that excess Si (g) (increased partial pressure) will affect the forward reaction rate of (4); from the chemical reaction equation (5), it can be seen that excess Si (g) (increased partial pressure) will also affect the forward reaction rate of (5). Therefore, the Si-rich atmosphere is the root cause of the reduced crystal growth rate during the growth process.

[0011] In addition, the density of Si(g) atmosphere in the system is lower than that of Si2C(g) and SiC2(g). Therefore, in the thermal field structure of the present application, the Si atmosphere accumulated during the SiC deposition process will tend to diffuse and distribute at the top of the crucible, and the Si2C(g) and SiC2(g) atmospheres volatilized from the powder will tend to distribute at the bottom of the crucible, that is, the C / Si ratio of the atmosphere in the seed crystal area is higher than that of the traditional structure. This distribution of atmosphere components is completely different from that under the traditional PVT structure. In this atmosphere distribution method, the surface of the single crystal growth seed crystal will not be overly enriched with Si, that is, the growth rate will remain at a higher level in the initial stage. At the same time, the Si atmosphere enriched at the top will continue to react with the high-purity carbon powder stored in the carbon powder area at the top of the crucible body, thereby increasing the C concentration in the gas phase component, which is further transported to the crystal area and increases the crystal growth rate.

[0012] Preferably, the silicon carbide powder area includes a powder crucible surrounding the inner wall of the crucible body for storing silicon carbide powder source, and an air flow channel for gas circulation is also provided at the center of the powder crucible.

[0013] The design of the powder crucible surrounding the inner wall of the crucible body in the present application greatly increases the contact area between the silicon carbide powder source and the high temperature environment. The larger contact area allows the silicon carbide powder source to be heated more fully, accelerates the volatilization rate, and provides more sufficient gas phase raw materials for subsequent deposition on the seed crystal in the low temperature zone, which helps to increase the growth rate of the silicon carbide single crystal.

[0014] In addition, the powder crucible is distributed around the inner wall, so that the powder source is heated relatively evenly in the circumferential direction, which is conducive to the uniform volatilization of the silicon carbide powder source. This is crucial for forming a uniform vapor deposition on the surface of the seed crystal and then growing high-quality and uniform silicon carbide single crystals.

[0015] Preferably, an annular support plate is provided on the inner wall of the high temperature zone, and the powder crucible is arranged on the upper end of the annular support plate.

[0016] Preferably, there is a gap between the top of the silicon carbide powder area and the carbon powder area, thereby forming a silicon carbide evaporation area.

[0017] Under high temperature environment, silicon carbide powder begins to volatilize in the powder area, and the evaporation area allows silicon carbide enough space to fully evaporate and transform into gas phase. Compared with the situation without a dedicated evaporation area, this design can avoid the inability of silicon carbide powder to completely evaporate due to limited space, improve the evaporation efficiency of silicon carbide, and provide sufficient gas phase raw materials for subsequent crystal growth.

[0018] Preferably, the crucible body comprises, from top to bottom, a crucible top cover, a crucible tube and a seed crystal cover; The carbon powder area is arranged below the crucible top cover, and the seed crystal is bonded to the top of the seed crystal cover.

[0019] Preferably, the exterior of the crucible body is coated with a layer of heat-insulating material; The thickness of the heat-insulating material in the top region of the crucible top cover is greater than the thickness of the heat-insulating material in the bottom region of the seed crystal cover.

[0020] During the growth of silicon carbide single crystals, the high-temperature zone needs to maintain a high and stable temperature to promote the volatilization and reaction of raw materials such as silicon carbide powder source and carbon powder. The insulation material in the top area of ​​the crucible top cover is thicker, which can effectively reduce the heat loss from the high-temperature zone to the outside through the top, ensure that the temperature of the high-temperature zone is maintained within a suitable range, and provide a stable high-temperature environment for the volatilization and reaction of the raw materials, which is conducive to improving the efficiency and consistency of the reaction. The insulation material in the bottom area of ​​the seed crystal cover is relatively thin, so that the low-temperature zone (the area where the seed crystal is located) can have a certain amount of heat exchange with the external environment, thereby forming a suitable temperature gradient from the high-temperature zone to the low-temperature zone in the crucible. This temperature gradient is very critical for guiding the transportation of gas-phase raw materials from the high-temperature zone to the low-temperature zone and the deposition and growth on the surface of the seed crystal. It can promote the growth of silicon carbide crystals in the expected direction and manner, and improve the growth quality and integrity of the crystal.

[0021] This application provides more stable thermodynamic conditions for the growth of silicon carbide single crystals by optimizing temperature distribution and reducing heat fluctuations. Stable growth conditions are conducive to the uniform growth of crystals and reduce crystal defects caused by temperature changes, such as stress concentration and lattice distortion, thereby improving the quality and performance consistency of silicon carbide single crystals.

[0022] Preferably, the heat-insulating material is provided with a heat-dissipating hole connected to the seed crystal cover at the center of the bottom of the seed crystal cover.

[0023] The heat dissipation holes provide additional heat dissipation channels for the seed crystal cover and the seed crystal area, which helps to more effectively dissipate the heat generated during the seed crystal growth process. Since silicon carbide crystal growth is very sensitive to temperature, precise control of the seed crystal temperature is crucial to the quality and growth direction of the crystal. The heat dissipation holes can prevent the seed crystal area from being overheated due to heat accumulation, ensure that the seed crystal is within the appropriate growth temperature range, and help improve the quality and stability of crystal growth.

[0024] Preferably, the filtering device comprises an upper filter plate arranged at the bottom of the carbon powder area and a lower filter plate arranged between the powder crucible and the seed crystal.

[0025] The setting of the upper filter plate can ensure that carbon particles cannot fall from the pores of the upper filter plate, while the lower filter plate can prevent the powder, carbon particles and other accidental particles on the upper part of the crucible from falling and forming inclusions in the silicon carbide single crystal at the bottom of the crucible and inducing defects such as polycrystalline, polymorphic, microtubules, dislocations, etc. Therefore, the present application makes the substances involved in crystal growth purer and the airflow more uniform and stable through the synergistic effect of the upper filter plate and the lower filter plate, thereby ensuring the consistency of the composition and structure of the silicon carbide crystal during the growth process.

[0026] Preferably, a support pad for supporting the upper filter plate and the lower filter plate is arranged inside the crucible body.

[0027] Preferably, the inner wall surface of the crucible body is provided with an anti-corrosion coating.

[0028] During the growth of silicon carbide single crystals, substances such as carbon powder and silicon carbide powder in the crucible may react chemically with the inner wall of the crucible at high temperatures, causing corrosion to the crucible. Anti-corrosion coatings can act as a barrier to prevent these substances from directly contacting the inner wall of the crucible, reducing the occurrence of chemical erosion and thus extending the service life of the crucible. If the inner wall of the crucible is corroded, the corrosion products may be mixed into the silicon carbide powder or the growth environment, becoming impurities and affecting the purity and quality of the silicon carbide crystals. Anti-corrosion coatings can effectively avoid this situation, ensure the purity of the crystal growth environment, and help grow high-quality, low-defect silicon carbide crystals.

[0029] Therefore, this application has the following beneficial effects: The present application effectively changes the diffusion direction and distribution mode of the gas used for silicon carbide single crystal deposition by changing the setting direction of the high-temperature zone and the low-temperature zone inside the crucible body, so that Si will not be excessively enriched on the surface of the seed crystal, thereby improving the crystal growth rate and ensuring that the single crystal growth rate is always maintained at a high level at the initial stage of deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of the high-efficiency silicon carbide single crystal growth device of the present invention.

[0031] Figure 2 Schematic diagram of the structure of a traditional growth furnace in a comparative application example.

[0032] Wherein: crucible body 1, high temperature zone 2, low temperature zone 3, silicon carbide powder zone 4, carbon powder zone 5, seed crystal 6, filtering device 7, powder crucible 8, air flow channel 9, silicon carbide evaporation zone 10, crucible tube 12, seed crystal cover 13, thermal insulation material 14, heat dissipation holes 15, upper filter plate 16, lower filter plate 17, support pad 18, annular support plate 19, upper seed crystal cover 20, lower crucible body 21. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with specific embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only embodiments of a part of the present invention, rather than all embodiments. Therefore, based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work should fall within the scope of protection of the present invention.

[0034] Example 1 like Figure 1 As shown, the present application provides a high-efficiency silicon carbide single crystal growth device, which includes a crucible body 1 made of isostatic graphite, and the crucible body 1 is composed of a crucible top cover 11, a crucible tube 12 and a seed crystal cover 13 connected by threaded tight fit from top to bottom. In addition, the outside of the crucible body 1 is also coated with a layer of heat-insulating material 14.

[0035] Different from the prior art, in this embodiment, the thickness of the heat-insulating material 14 at the top area of ​​the crucible top cover 11 is greater than the thickness at the bottom area of ​​the seed crystal cover 13, so that the heat-insulating effect above the crucible body 1 near the crucible top cover 11 is better than the heat-insulating effect below the crucible body 1 near the seed crystal cover 13. With such an arrangement, when the silicon carbide single crystal growth device is heated by an external heat source during operation, the inside of the crucible body 1 can be divided into a high-temperature zone 2 near the top of the crucible body 1 and a low-temperature zone 3 near the bottom of the crucible body 1 from top to bottom according to the temperature zone distribution.

[0036] In order to further increase the temperature difference between the low temperature zone 3 and the high temperature zone 2, in another preferred embodiment of the present application, a heat dissipation hole 15 connected to the seed crystal cover 13 is provided at the center of the bottom of the seed crystal cover 13 on the thermal insulation material 14, thereby improving the heat dissipation efficiency of the low temperature zone 3 and facilitating improving the quality and stability of crystal growth.

[0037] The middle and upper part of the crucible tube 12 is provided with a powder crucible 8 for storing silicon carbide powder source around the inner wall of the crucible body 1, which is also made of isostatic graphite, so the area where the powder crucible 8 is located is named as silicon carbide powder area 4. In order to allow the silicon carbide sublimation gas generated in the silicon carbide powder area 4 to flow out quickly, there is a certain distance between the top of the silicon carbide powder area 4 and the carbon powder area 5 in this embodiment, thereby forming a silicon carbide evaporation area 10. At the same time, in order to stably fix the powder crucible 8 inside the crucible body 1, in another preferred embodiment, the inner wall of the high temperature zone 2 is provided with an annular support plate 19, so that the powder crucible 8 can be fixedly mounted on the upper end of the annular support plate 19.

[0038] In addition, in a preferred embodiment of the present application, a gas flow channel 9 is provided at the center of the powder crucible 8 to allow the gas in the high temperature zone 2 and the low temperature zone 3 to communicate with each other, so that the sublimation gas formed by the silicon carbide powder in the powder crucible 8 after high temperature sublimation can enter the low temperature zone 3 from the high temperature zone 2 along the gas flow channel 9. At the same time, in order to adapt to the flow direction of the silicon carbide sublimation gas, a seed crystal 6 is provided on the top of the seed crystal cover 13 located at the bottom of the crucible body 1 in this embodiment, so that after the silicon carbide sublimation gas flows to the area where the seed crystal 6 is located, it can gradually deposit silicon carbide crystals on the surface of the seed crystal 6.

[0039] In addition, since the volatile gas volatilized in the powder crucible 8 contains different gases such as Si gas, SiC2 gas, Si2C gas, and since the density of Si gas is lower than that of SiC2 gas and Si2C gas, respectively, in the thermal field structure of this embodiment, the Si atmosphere accumulated during the silicon carbide deposition process will tend to diffuse and distribute at the crucible top cover 11, and the Si2C and SiC2 atmospheres volatilized by the powder tend to distribute at the seed crystal cover 13 at the bottom of the crucible. Therefore, the atmosphere in the area where the seed crystal 6 is located in this application has a higher C / Si ratio than the traditional structure. This distribution mode of atmosphere components is completely different from the distribution mode under the traditional PVT structure. Under this atmosphere distribution mode, it can maintain that the surface of the single crystal growth seed crystal will not be overly enriched with Si gas, that is, the growth rate can always be maintained at a high level at the initial stage of silicon carbide crystal deposition.

[0040] At the same time, in order to better utilize the Si atmosphere enriched at the crucible top cover 11, in a preferred embodiment of the present application, a carbon powder area 5 for containing carbon powder is provided below the crucible top cover 11. Therefore, the Si atmosphere enriched at the crucible top cover 11 can react with the high-purity carbon powder placed in the crucible to form SiC2 gas and Si2C gas, thereby increasing the C concentration in the gas phase component, which is further transported to the crystal area and the crystal growth rate is improved.

[0041] Since silicon carbide powder and carbon powder are easily dropped onto the surface of the seed crystal along with the airflow during the sublimation of silicon carbide, they are thus wrapped by the silicon carbide single crystal and induce defects such as polycrystalline, polymorphic, microtubes, and dislocations. Therefore, in a preferred embodiment of the present application, a filtering device 7 for filtering solid particles dropped onto the surface of the seed crystal 6 is further provided inside the crucible body 1.

[0042] Specifically, the filtering device 7 includes two parts: an upper filter plate 16 disposed at the bottom of the carbon powder area 5 and a lower filter plate 17 disposed between the powder crucible 8 and the seed crystal, both of which are disposed on the upper end of the support pad 18 inside the crucible body 1. The porosity of the upper filter plate 16 is much smaller than the particle size of the carbon powder to ensure that the carbon particles cannot fall from the pores of the upper filter plate. The lower filter plate 17 is disposed at a distance of 3-10 cm from the seed crystal cover, and the distance can be adjusted according to the expected crystal growth thickness to reserve sufficient space. At the same time, the lower filter plate 17 can prevent the powder, carbon particles and other accidental particles on the upper part of the crucible from falling.

[0043] In order to enable the upper filter plate 16 and the lower filter plate 17 to be able to be used for a long time in a SiC crystal growth atmosphere, the materials thereof may include but are not limited to TaC porous materials or other high temperature resistant and corrosion resistant carbides, nitrides and other materials, such as tungsten carbide, hafnium carbide, etc. At the same time, in some preferred embodiments, the inner wall of the crucible body 1 is coated with corrosion resistant materials, including but not limited to tantalum carbide coating, so as to further inhibit the pollution of carbon particles.

[0044]

Application examples

[0045] Step 2: In a Class 100 clean room, assemble the seed crystal cover 13 and the crucible tube 12; the surface of the crucible tube 12 has been pre-prepared with an anti-corrosion coating, including but not limited to TaC coating material, and the coating thickness is not less than 20 microns; the surface of the seed crystal 6 bonded to the surface of the seed crystal cover 13 has completed deep cleanliness treatment.

[0046] Step 3: Assemble the lower filter plate 17 to form a clean chamber in the space where the seed crystal 6 is located.

[0047] Step 4: In a Class 1000 clean room, the raw materials mixed with carbon powder and silicon carbide powder are loaded into the powder crucible 8. The weight ratio of carbon powder to SiC powder is in the range of 1% to 10%; the particle size of carbon powder is 50 to 150 microns; the particle size of SiC is 500 to 2000 microns. The purity of SiC powder and C powder is better than 6N. Carbon powder and SiC powder use a two-level mesh screen to strictly control the particle size range of the powder.

[0048] Step 5: In a Class 1000 clean room, assemble the powder crucible 8 in 4 and the crucible carrying the seed crystal 6 in the low temperature zone 3 .

[0049] Step 6: Based on step 5, load the filter plate 16.

[0050] Step 7: Load the carbon powder on the top of the crucible based on step 6. The particle size of the carbon powder is 50~500 microns, and the purity is better than 6N. Among them, the carbon powder uses a two-level mesh screen to strictly control the particle size distribution range of the powder. The amount of carbon powder is obtained according to the chamber volume and the tap density of the carbon powder, and the general amount is 0.1~1kg.

[0051] Step 8: Based on step 7, assemble the crucible top cover 11.

[0052] Step 9: Assemble the heat-insulating material 14 and design the thickness of the heat-insulating material 14 to ensure that the temperature at the top of the crucible body 1 is higher than the temperature at the bottom of the crucible body 1 , and the typical temperature gradient is 30-200 degrees Celsius.

[0053] Step 10: According to the traditional SIC crystal growth process, the crystal growth rate needs to be adjusted during the initial crystal growth process, the temperature of the seed crystal cover 13 is controlled at 2000-2250 degrees Celsius, and the growth pressure is controlled at 1-20 mbar. The crystal growth adjustment time is 5-20 hours.

[0054] Step 11: After the crystal growth is completed, measure the crystal weight and estimate the crystal growth rate based on the result.

[0055] Step 12: Formal growth. The growth time can be estimated based on the powder loading, the distance between the lower filter plate 17 and the seed crystal, and the crystal growth rate in step 11. The crystal growth step repeats the above steps 1 to 11, except that high-quality seed crystals are required in step 2, and the formal crystal growth time in step 10 is generally 80 to 150 hours.

[0056]

Comparative application example

[0057] Under this traditional PVT growth furnace structure, the crystal growth method operation steps are as follows: Step 1: Filling silicon carbide powder source particles into the lower crucible body 21; Step 2: Evacuate the inside of the growth furnace, open the vacuum port and the vacuum pump, and close the vacuum pump and the vacuum port valve after the vacuum degree inside the growth furnace reaches the required level; Step 3: Set the heater heating strategy, turn on the electromagnetic coil to heat the crucible, control the temperature of the upper seed crystal cover 20 at 2100° C., control the growth gas pressure at 15 mbar, and the bottom temperature of the lower crucible body 21 is higher than 2250° C.; Step 4: After the crystal has grown stably for 10 hours, turn off the power of the electromagnetic coil, allow the crystal to cool naturally in the furnace, and calculate the crystal growth rate.

[0058] The crystal growth rates of silicon carbide crystals in the application examples and the comparative application examples are shown in Table 1 below.

[0059] Table 1 project Crystal growth rate Crystal defects Crystal limit thickness Application Examples ~0.3mm / h <![CDATA[EPD~2000ea / cm 2 ]]> >4cm Comparative Application Examples ~0.15mm / h <![CDATA[EPD~3000ea / cm 2 ]]> <3cm (increasing thickness will result in a decrease in crystal quality) It can be seen from the data in the above table that the high-efficiency silicon carbide single crystal growth device in the present application can effectively increase the growth rate of silicon carbide crystals and effectively reduce the defect rate of the grown silicon carbide crystals.

[0060] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A high-efficiency silicon carbide single crystal growth device, characterized in that: The crucible body (1) comprises a crucible main body (1), wherein the crucible main body (1) is divided into a high temperature zone (2) and a low temperature zone (3) from top to bottom according to temperature zone distribution, and the high temperature zone (2) and the low temperature zone (3) are interconnected; wherein: A silicon carbide powder material area (4) for containing a silicon carbide powder source is provided in the high temperature area (2), and a carbon powder area (5) for containing carbon powder is also provided on the top of the high temperature area (2); A seed crystal (6) for depositing silicon carbide crystals is bonded to the bottom of the low temperature zone (3); A filtering device (7) for filtering solid particles that fall onto the surface of the seed crystal (6) is also provided inside the crucible body (1).

2. A high-efficiency silicon carbide single crystal growth device according to claim 1, characterized in that: The silicon carbide powder area (4) comprises a powder crucible (8) surrounding the inner wall of the crucible body (1) for storing a silicon carbide powder source, and a gas flow channel (9) for gas circulation is also provided at the center of the powder crucible (8).

3. A high-efficiency silicon carbide single crystal growth device according to claim 2, characterized in that: An annular support plate (19) is provided on the inner wall of the high temperature zone (2), and the powder crucible (8) is arranged on the upper end of the annular support plate (19).

4. A high-efficiency silicon carbide single crystal growth device according to claim 1, 2 or 3, characterized in that: There is a gap between the top of the silicon carbide powder area (4) and the carbon powder area (5), thereby forming a silicon carbide evaporation area (10).

5. The high-efficiency silicon carbide single crystal growth device according to claim 1, characterized in that: The crucible body (1) comprises, from top to bottom, a crucible top cover (11), a crucible tube (12) and a seed crystal cover (13); The carbon powder area (5) is arranged below the crucible top cover (11), and the seed crystal (6) is bonded to the top of the seed crystal cover (13).

6. A high-efficiency silicon carbide single crystal growth device according to claim 1 or 5, characterized in that: The exterior of the crucible body (1) is coated with a layer of heat-insulating material (14); The thickness of the heat-insulating material (14) located in the top area of ​​the crucible top cover (11) is greater than the thickness of the heat-insulating material located in the bottom area of ​​the seed crystal cover (13).

7. A high-efficiency silicon carbide single crystal growth device according to claim 6, characterized in that: The heat-insulating material (14) is provided with a heat-dissipating hole (15) at the center of the bottom of the seed crystal cover (13) and is connected to the seed crystal cover (13).

8. The high-efficiency silicon carbide single crystal growth device according to claim 1, characterized in that: The filtering device (7) comprises an upper filtering plate (16) arranged at the bottom of the carbon powder area (5) and a lower filtering plate (17) arranged between the powder crucible (8) and the seed crystal.

9. The high-efficiency silicon carbide single crystal growth device according to claim 8, characterized in that: A support pad (18) for supporting an upper filter plate (16) and a lower filter plate (17) is arranged inside the crucible body (1).

10. The high-efficiency silicon carbide single crystal growth device according to claim 1, characterized in that: The inner wall surface of the crucible body (1) is provided with an anti-corrosion coating.

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