Device for growing single-furnace multi-group silicon carbide crystals by liquid phase method and use method of device

Abstract

The invention belongs to the field of silicon carbide single crystal growth, and particularly relates to single crystal growth of a melt liquid pulling method, in particular to a device for growing single-furnace multi-group silicon carbide crystals by a liquid phase method and a use method of the device. The device for growing the single-furnace multi-group silicon carbide crystals by the liquid phase method comprises a graphite crucible, a heating assembly, a driving mechanism and a lifting and rotating mechanism, the graphite crucible comprises a crucible body and a separation ring, the separating ring is arranged in the crucible body and is used for separating the crucible body into an inner groove and an outer groove which are concentric. The structure of the graphite crucible is reset, the crucible body is divided into the inner groove and the outer groove, the cosolvent is placed in the outer groove, and the seed crystal is placed in the inner groove, so that the problem that the cosolvent can melt through the seed crystal when the seed crystal is placed in the crucible in the prior art is solved, and simultaneous growth of multiple groups of silicon carbide crystals in a single furnace is realized; and the growth cost of the silicon carbide crystal is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of silicon carbide single crystal growth, and specifically relates to single crystal growth by a molten liquid pulling method, and in particular to a device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method and a method for using the device. Background Art

[0002] The essence of growing silicon carbide crystals by the liquid phase method is to dissolve the carbon solute through the solvent in the graphite crucible. Driven by the temperature gradient, the solute reaches supersaturation at the seed crystal growth interface, and then silicon carbide crystals are precipitated to achieve epitaxial growth of the crystal.

[0003] In the related art, when growing silicon carbide crystals, only the growth method of single-furnace single crystal can be adopted, which results in excessively high production costs of silicon carbide crystals. If multiple seed crystals are pulled at the same time, the temperature gradients of the pulled and grown seed crystals will conflict, and the low-temperature zones of different seed crystals will overlap or squeeze each other, resulting in disordered temperature gradients and unbalanced melt distribution, affecting the quality of the crystals, such as the appearance of macroscopic steps. Therefore, it is impossible to achieve the growth of multiple silicon carbide crystals in a single furnace by simultaneously pulling multiple seed crystals for crystal growth. If the seed crystals are placed directly at the bottom of the crucible, since the density of the solubilizer is greater than that of silicon (Si), they will sink to the bottom of the molten liquid. During growth, the seed crystals at the bottom of the crucible will contact the solubilizer, causing the seed crystals to melt through. Therefore, it is impossible to set seed crystals at the bottom of the crucible to achieve the growth of multiple groups of silicon carbide crystals in a single furnace.

[0004] Therefore, how to achieve the simultaneous growth of multiple groups of silicon carbide crystals in a single furnace to reduce the growth cost of silicon carbide crystals is a technical problem that needs to be solved urgently.

[0005] It should be noted that the above information disclosed in this background technology section is only used to understand the background technology of the present application concept, and therefore, the above description is not considered to constitute information of the prior art. Summary of the invention

[0006] The embodiments of the present disclosure at least provide a device for growing multiple groups of silicon carbide crystals in a single furnace using a liquid phase method and a method for using the same.

[0007] In a first aspect, an embodiment of the present disclosure provides a device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method, comprising: A graphite crucible, which is used to hold raw materials; A heating assembly, which is arranged around the graphite crucible and is used to heat the raw materials in the crucible; A driving mechanism, which is arranged below the graphite crucible and is used to drive the graphite crucible to rotate; A lifting and rotating mechanism, which is arranged above the graphite crucible, and the bottom of which is used to place seed crystals for crystal growth; Wherein, the graphite crucible comprises: Crucible body and separator ring; The separation ring is disposed in the crucible body and is used to separate the crucible body into a concentric inner groove and an outer groove; The inner tank is used to place Si blocks in the raw materials; the outer tank is used to place the co-solvent; The bottom of the inner tank is provided with a mounting groove; During crystal growth, seed crystals are placed in the mounting groove and at the bottom of the lifting and rotating mechanism, respectively, and a plurality of silicon carbide crystals are grown simultaneously.

[0008] In an optional embodiment, the height of the crucible body is H1; The height of the separation ring is H2; Wherein, H1>H2, and the units of H1 and H2 are mm.

[0009] In an optional embodiment, the radius of the inner groove is R1; The radius of the outer groove is R2; Among them, 1.5R1<R2<2R1, and the units of R1 and R2 are mm.

[0010] In an optional embodiment, the depth of the mounting groove is h; Among them, h<L, where L is the thickness of the seed crystal; Moreover, the range of h is between 0.5 mm and 1 mm.

[0011] In an optional embodiment, the bottom height of the inner groove is higher than the bottom height of the outer groove; When the driving mechanism drives the graphite crucible to rotate, the separation ring blocks the auxiliary solvent from entering the inner tank.

[0012] In an optional embodiment, the outer tank of the graphite crucible is further provided with a plurality of stirring rods; A plurality of stirring rods are arranged along the circumference of the outer tank and connected to the bottom of the outer tank; When the driving mechanism drives the graphite crucible to rotate, the molten liquid in the outer tank is stirred by the stirring rod.

[0013] In an optional embodiment, the stirring rods include multiple groups; The number of stirring rods in each group of stirring rods is two; A guide inclined plate is provided between two stirring rods in each group of stirring rods; Furthermore, the guiding direction of the guiding inclined plate is opposite to the rotation direction of the graphite crucible.

[0014] In an optional embodiment, the guide inclined plate includes a first curved plate and a second curved plate; The outer arc side of the second arc plate is connected to the inner arc side of the first arc plate; Furthermore, the second arc-shaped plate is arranged to be inclined downward, so as to guide the auxiliary solvent downward when the driving mechanism drives the graphite crucible to rotate, thereby facilitating the stratification of the melted carbon and the auxiliary solvent.

[0015] In an optional embodiment, the bottom of the guide inclined plate is lower than the bottom of the inner groove; Furthermore, the top of the guide inclined plate is lower than the top of the separation ring.

[0016] In an optional embodiment, the stirring rod is threadedly connected to the bottom of the outer tank; Two stirring rods in each group of stirring rods are respectively provided with overlapping blocks; A side wall of one of the overlapping blocks is provided with an overlapping groove; One end of the guide inclined plate is inserted into the overlapping groove, and the other end is overlapped with another overlapping block, and the outer side wall of the guide inclined plate is abutted against the side wall of the outer groove; When the inclination angle a of the guide inclined plate needs to be adjusted, the height of the overlap block is adjusted by screwing the corresponding stirring rod to complete the adjustment of the inclination angle of the guide inclined plate.

[0017] In a second aspect, the embodiments of the present disclosure further provide a method for using the above-mentioned device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method, the method comprising: Bonding seed crystals to the bottom of the lifting and rotating mechanism and in the mounting groove respectively; The Si block is placed in the inner tank of the graphite crucible, and the co-solvent is placed in the outer tank; Controlling the heating component to heat the graphite crucible until the solvent is completely melted to obtain a melt; Control the driving mechanism to drive the graphite crucible to rotate; Adjust the position of the high temperature wire of the heating assembly so that the high temperature wire is in the middle of the molten liquid in the inner tank; The pulling and rotating mechanism is controlled to make the seed crystal at the bottom of the pulling and rotating mechanism contact with the melt, and the pulling and rotating mechanism is continuously rotated to make the bottom of the pulling and rotating mechanism and the seed crystal bonded in the installation groove grow simultaneously.

[0018] The beneficial effect of the present invention is that the device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method re-arranges the structure of the graphite crucible, divides the crucible body into an inner groove and an outer groove, places the solvent in the outer groove, and places the seed crystal in the inner groove, thereby solving the problem in the related art that the seed crystal is placed in the crucible and the solvent will melt through the seed crystal, thereby achieving the simultaneous growth of multiple groups of silicon carbide crystals in a single furnace and reducing the growth cost of silicon carbide crystals.

[0019] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, this article specifically cites preferred embodiments and provides detailed descriptions as follows in conjunction with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method provided in the embodiment of the present disclosure; Figure 2 A schematic diagram of the structure of a graphite crucible provided in an embodiment of the present disclosure; Figure 3 A cross-sectional view of a graphite crucible provided in an embodiment of the present disclosure; Figure 4 A cross-sectional view of a graphite crucible from another perspective provided in an embodiment of the present disclosure; Figure 5 A schematic diagram of the structure of the guide inclined plate provided in the embodiment of the present disclosure; Figure 6 A flow chart of a method for growing multiple groups of silicon carbide crystals in a single furnace using a liquid phase method according to an embodiment of the present disclosure; Figure 7 A schematic diagram of the overlap between a group of stirring rods and a guide ramp of a graphite crucible provided in an embodiment of the present disclosure.

[0023] In the figure: 100, graphite crucible; 110, crucible body; 120, separator ring; 130, inner groove; 131, mounting groove; 140, outer groove; 141, stirring rod; 141a, overlapping block; 141b, overlapping groove; 142, guide inclined plate; 142a, first arc plate; 142b, second arc plate; 200, heating assembly; 300, driving mechanism; 400, pulling and rotating mechanism; 500, seed crystal. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0025] After research, it was found that there are two single-furnace multi-group seed crystal growth methods in the related technology. The first method, which uses the method of pulling multiple seed crystals at the same time, will lead to temperature gradient conflicts in the pulled growing seed crystals. The low-temperature zones of different seed crystals will overlap or squeeze each other, resulting in temperature gradient disorder and unbalanced melt distribution. The multiple silicon carbide crystals generated have obvious macroscopic steps and cannot meet the use requirements. The second method, which uses the method of placing the seed crystals at the bottom of the crucible, will cause the seed crystals to be melted through by the solvent, and silicon carbide crystals cannot be obtained.

[0026] Based on the above research, an embodiment of the present disclosure provides a device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method and a method of using the device. By improving the structure of the crucible, the graphite crucible 100 is divided into two grooves, and the solvent and the seed crystal 500 are placed in different grooves at the same time. Without affecting the growth of the seed crystal 500 at the bottom of the pulling and rotating mechanism 400, multiple silicon carbide crystals can be generated. The silicon carbide crystals grown from the seed crystal 500 in the crucible can meet the use requirements after proper cutting, thereby realizing the simultaneous growth of multiple groups of silicon carbide crystals in a single furnace.

[0027] The defects existing in the above solutions are the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the present invention in this article for the above problems should be the contributions made by the inventor to the present invention during the disclosure process.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0030] See also Figure 1 and Figure 2 At least one embodiment provides a device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method, comprising the following structure: The graphite crucible 100 is used to hold the raw material. The graphite in the graphite crucible 100 is dissolved by the solvent in the raw material to provide carbon (C) to the melt.

[0031] Among them, the solvent is one or more of Cr, Al, Sc, Co, Ti, Fe, and Sn.

[0032] The heating assembly 200 is disposed around the graphite crucible 100 and is used to heat the raw materials in the crucible.

[0033] Among them, the heating component 200 includes an insulation layer, a heating coil and a lifting mechanism; the insulation layer 210 is wrapped around the graphite crucible 100; the heating coil is wrapped around the insulation layer and is used to heat the graphite crucible 100, and the middle of the heating coil is the hottest point, that is, the high temperature line of the heating component 200 is located in the middle of the heating coil; the lifting mechanism is used to drive the heating coil to extend and retract, and the lifting speed of the lifting mechanism is the same as the lifting speed of the lifting and rotating mechanism 400.

[0034] The lifting mechanism can use a lifting cylinder or a push rod motor to push the lifting plate to lift the heating coil, so as to change the position of the high-temperature line of the heating coil.

[0035] The driving mechanism 300 is disposed below the graphite crucible 100 and is used to drive the graphite crucible 100 to rotate. The driving mechanism 300 can realize the rotation of the graphite crucible 100 by means of a rotating motor and a rotating table.

[0036] The lifting and rotating mechanism 400 is disposed above the graphite crucible 100 , and the bottom of the lifting and rotating mechanism 400 is used to place a seed crystal 500 for crystal growth.

[0037] The structure of the lifting and rotating mechanism 400 is a prior art. Specifically, a linkage structure of a lifting cylinder and a rotating motor can be used to realize rotation and lifting.

[0038] Please continue reading Figure 1 and 2, wherein the graphite crucible 100 includes: a crucible body 110 and a separator ring 120; the separator ring 120 is arranged in the crucible body 110, and is used to separate the crucible body 110 into a concentric inner groove 130 and an outer groove 140; the inner groove 130 is used to place Si blocks in the raw material; the outer groove 140 is used to place the solvent; the bottom of the inner groove 130 is provided with a mounting groove 131; when the crystal grows, the seed crystal 500 is respectively placed in the mounting groove 131 and the bottom of the pulling and rotating mechanism 400, and multiple silicon carbide crystals are grown at the same time.

[0039] By re-arranging the structure of the graphite crucible 100, the crucible body 110 is divided into an inner groove 130 and an outer groove 140, the flux is placed in the outer groove 140, and the seed crystal 500 is placed in the inner groove 130, thereby solving the problem in the related art that the flux will melt through the seed crystal 500 when the seed crystal 500 is placed in the crucible, thereby achieving the simultaneous growth of multiple groups of silicon carbide crystals in a single furnace, and reducing the growth cost of silicon carbide crystals.

[0040] See also Figure 3 , the height of the crucible body 110 is H1; the height of the separation ring 120 is H2; wherein H1>H2, and the units of H1 and H2 are mm. Since the height H2 of the separation ring 120 is lower than the height H1 of the crucible body 110, the melted carbon enters the inner groove 130 for crystal growth.

[0041] The radius of the inner groove 130 is R1; the radius of the outer groove 140 is R2; 1.5R1<R2<2R1, and the units of R1 and R2 are mm. By reasonably setting the sizes of R1 and R2, the carbon dissolution rate is limited so that the carbon dissolution rate meets the growth requirements of multiple seed crystals 500.

[0042] It should be noted that the depth of the mounting groove 131 is h, where h<L, where L is the thickness of the seed crystal 500, and h is in the range of 0.5 mm to 1 mm. The thickness of the seed crystal 500 is greater than the depth of the mounting groove 131, so that crystal growth on the surface of the seed crystal 500 is facilitated.

[0043] In a preferred embodiment, the bottom height of the inner tank 130 is higher than the bottom height of the outer tank 140; when the driving mechanism 300 drives the graphite crucible 100 to rotate, the separation ring blocks the flux from entering the inner tank 130. By deepening the depth of the outer tank 140 to reduce the liquid level of the melted flux, the amount of the flux entering the inner tank 130 during rotation is reduced, further preventing the seed crystal 500 from being melted through.

[0044] See also Figures 2 to 4The outer tank 140 of the graphite crucible 100 is also provided with a plurality of stirring rods 141; the plurality of stirring rods 141 are arranged along the circumference of the outer tank 140 and connected to the bottom of the outer tank 140; when the driving mechanism 300 drives the graphite crucible 100 to rotate, the stirring rods 141 are used to stir the molten liquid in the outer tank 140. The stirring rods 141 accelerate the stratification of the co-solvent and the molten carbon. Since the density of the co-solvent is relatively large, it will gradually sink to the bottom during stirring, and the molten carbon will be located above the molten liquid, which is convenient for the growth of silicon carbide.

[0045] In order to accelerate the sinking of the solvent, the stirring rods 141 include multiple groups; the number of stirring rods 141 in each group of the stirring rods 141 is two; a guide inclined plate 142 is arranged between the two stirring rods 141 in each group of the stirring rods 141; and the guide direction of the guide inclined plate 142 is opposite to the rotation direction of the graphite crucible 100.

[0046] The molten liquid at the bottom of the outer tank 140 is lifted by the guide inclined plate 142, so as to promote the separation of the flux and the melted carbon.

[0047] The rotation direction of the graphite crucible 100 is as follows: Figure 2 As shown in F1, the diversion direction of the diversion inclined plate 142 is as follows: Figure 2 As shown in F2.

[0048] See also Figure 5 The guide inclined plate 142 includes a first curved plate 142a and a second curved plate 142b; the outer curved side of the second curved plate 142b is connected to the inner curved side of the first curved plate 142a; and the second curved plate 142b is tilted downward so that when the driving mechanism 300 drives the graphite crucible 100 to rotate, the auxiliary solvent is guided downward, thereby facilitating the stratification of the melted carbon and the auxiliary solvent.

[0049] See also Figure 3 The bottom of the guide plate 142 is lower than the bottom of the inner tank 130, and the top of the guide plate 142 is lower than the top of the separation ring 120. By limiting the position of the guide plate 142, the guide plate 142 is prevented from introducing the co-solvent into the inner tank 130, thereby reducing the amount of the co-solvent entering the inner tank 130.

[0050] See also Figure 3 and Figure 7In order to adapt to the pulling and growing requirements of seed crystals 500 of different sizes, the stirring rod 141 is threadedly connected to the bottom of the outer trough 140; two stirring rods 141 in each group of the stirring rods 141 are respectively provided with overlapping blocks 141a; a side wall of one of the overlapping blocks 141a is provided with an overlapping groove 141b; one end of the guide inclined plate 142 is inserted into the overlapping groove 141b, and the other end is overlapped with another overlapping block 141a, and the outer side wall of the guide inclined plate 142 is abutted against the side wall of the outer trough 140; when the inclination angle a of the guide inclined plate 142 needs to be adjusted, the height of the overlapping block 141a is adjusted by screwing the corresponding stirring rod 141 to complete the adjustment of the inclination angle a of the guide inclined plate 142.

[0051] By adjusting the inclination angle a of the guide inclined plate 142 , the carbon content entering the inner tank 130 is adjusted, thereby meeting the pulling growth requirements of seed crystals 500 of different sizes.

[0052] Among them, the range of a is between 15°-50°.

[0053] See also Figure 6 At least one embodiment further provides a method for using the above-mentioned device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method, the method comprising: Step S1, bonding the seed crystal 500 to the bottom of the lifting and rotating mechanism 400 and the mounting groove 131 respectively; Step S2, placing the Si block in the inner tank 130 of the graphite crucible 100, and placing the co-solvent in the outer tank 140; Step S3, controlling the heating assembly 200 to heat the graphite crucible 100 until the solvent is completely melted to obtain a melt; Step S4, controlling the driving mechanism 300 to drive the graphite crucible 100 to rotate; Step S5, adjusting the position of the high temperature line of the heating assembly 200 so that the high temperature line reaches the middle of the molten liquid in the inner tank; Step S6, controlling the lifting and rotating mechanism 400 to make the seed crystal 500 at the bottom of the lifting and rotating mechanism 400 contact with the melt, and continuously rotating and lifting, so that the seed crystal 500 bonded to the bottom of the lifting and rotating mechanism and the mounting groove 131 simultaneously grows.

[0054] Example 1: Multiple groups of silicon carbide crystals are grown according to the above-mentioned device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method and its using method.

[0055] Here are the steps: Step 1: glue a 6-inch seed crystal 500 to the bottom of the seed crystal 500 rod of the lifting and rotating mechanism 400 , and glue three 2-inch seed crystals 500 to the central bottom mounting groove 131 of the graphite crucible 100 .

[0056] Step 2, after assembling the experimental device, close the furnace chamber, perform vacuum treatment, and then fill the furnace chamber with inert gas, place the Si block above the 2-inch seed crystal 500 in the inner groove 130 of the graphite crucible 100, and place the Cr block in the outer groove 140 of the graphite crucible 100, and heat the raw materials to completely melt.

[0057] Step 3: The graphite crucible 100 is rotated at a speed of 15 rpm.

[0058] Step 4, move the heating coil of the heating assembly 200 and adjust the high temperature line to the middle of the molten liquid in the inner tank; Step 5, lower the seed crystal 500 rod, and after the 6-inch seed crystal 500 contacts the liquid surface, it begins to grow by rotating and pulling at 30 rpm.

[0059] Finally, the 6-inch silicon carbide single crystal grown had a small number of steps on its surface, but no solvent inclusions; the three 2-inch silicon carbide crystals at the bottom were obtained after proper cutting, the growth surface was effectively melted back, and the whole was a single crystal without solvent inclusions, meeting the usage requirements.

[0060] Example 2: Multiple groups of silicon carbide crystals are grown according to the above-mentioned device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method and its using method.

[0061] Step 1: glue a 6-inch seed crystal 500 to the bottom of the seed crystal 500 rod of the lifting and rotating mechanism 400 , and glue three 2-inch seed crystals 500 to the central bottom mounting groove 131 of the graphite crucible 100 .

[0062] Step 2, after assembling the experimental device, close the furnace chamber, perform vacuum treatment, and then fill the furnace chamber with inert gas, place the Si block above the 2-inch seed crystal 500 in the inner groove 130 of the graphite crucible 100, and place the Cr block and the Al block in the outer groove 140 of the graphite crucible 100, and heat the raw materials to completely melt.

[0063] Step 3: The graphite crucible 100 is rotated at a speed of 15 rpm.

[0064] Step 4, move the heating coil of the heating assembly 200 and adjust the high temperature line to the middle of the molten liquid in the inner tank; Step 5, lower the seed crystal 500 rod, and after the 6-inch seed crystal 500 contacts the liquid surface, it begins to grow by rotating and pulling at 30 rpm.

[0065] Finally, the surface of the 6-inch silicon carbide single crystal grown was smooth without obvious macroscopic steps. The three 2-inch silicon carbide crystals at the bottom were obtained after proper cutting, and the growth surface was effectively melted back. The whole was a single crystal without solvent inclusions.

[0066] Through Examples 1 and 2, the effectiveness of the device for growing multiple groups of silicon carbide crystals in a single furnace using the liquid phase method and the method of using the device for growing multiple groups of silicon carbide crystals in a single furnace was verified.

[0067] In comparative example 1, the experimental steps are substantially the same as those in example 2, except that the rotation speed of the graphite crucible 100 is 20 rpm.

[0068] Finally, before the seed crystal rod 500 touched the liquid surface, a large number of silicon carbide floating crystals floated on the liquid surface, and the 6-inch silicon carbide crystal finally grown had a large number of polycrystalline attachments. The bottom 2-inch silicon carbide crystal was obtained after proper cutting, and the growth surface was effectively melted back, and the whole was a single crystal without solvent inclusions. This phenomenon shows that the rotation of the graphite crucible at 20rpm increased the heat dissipation of the liquid surface, increasing the risk of silicon carbide grains appearing on the free liquid surface, but had almost no effect on the growth of the bottom crystal.

[0069] In Comparative Example 2, the experimental steps are substantially the same as those of Example 2, except that the placement position of the raw materials in the graphite crucible 100 is different.

[0070] In Comparative Example 2, Si blocks and Cr blocks were mixed uniformly in advance and then placed in the inner and outer rings of the crucible.

[0071] Results Due to the high density of Cr in the process of smelting, it sank to the bottom of the crucible, causing the bottom seed crystal 500 to melt through, making it impossible to grow multiple groups of silicon carbide crystals in a single furnace at the same time.

[0072] In comparative example 3, the experimental steps are basically the same as those in example 2, except that the high temperature line is placed at the bottom of the graphite crucible 100 .

[0073] The surface of the 6-inch silicon carbide single crystal grown was smooth without obvious macroscopic steps, and the three 2-inch silicon carbide crystals at the bottom were completely dissolved under the action of high temperature.

[0074] From the above-mentioned Examples 1, 2 and Comparative Examples 1-3, it can be concluded that the device for growing multiple groups of silicon carbide crystals in a single furnace by the liquid phase method and the method of using the device can place the seed crystal 500 in the graphite crucible 100 to grow multiple silicon carbide crystals simultaneously, and will not affect the crystal growth of the seed crystal 500 pulled by the pulling rotating mechanism 400.

[0075] The beneficial effect of the present invention is that the present invention provides a device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method and a method for using the same, wherein the device for growing multiple groups of silicon carbide crystals in a single furnace by a liquid phase method comprises: a graphite crucible 100, which is used to hold raw materials; a heating assembly 200, which is arranged around the graphite crucible 100 and is used to heat the raw materials in the crucible; a driving mechanism 300, which is arranged below the graphite crucible 100 and is used to drive the graphite crucible 100 to rotate; a lifting and rotating mechanism 400, which is arranged above the graphite crucible 100 and has a bottom for placing seed crystals 5 00 for crystal growth; wherein the graphite crucible 100 includes: a crucible body 110 and a separator ring 120; the separator ring 120 is arranged in the crucible body 110, and is used to separate the crucible body 110 into a concentric inner groove 130 and an outer groove 140; the inner groove 130 is used to place Si blocks in the raw material; the outer groove 140 is used to place the solvent; the bottom of the inner groove 130 is provided with a mounting groove 131; when the crystal grows, the seed crystal 500 is respectively placed in the mounting groove 131 and the bottom of the pulling and rotating mechanism 400, and a plurality of silicon carbide crystals are grown at the same time. By re-arranging the structure of the graphite crucible 100, the crucible body 110 is divided into an inner groove 130 and an outer groove 140, the flux is placed in the outer groove 140, and the seed crystal 500 is placed in the inner groove 130, thereby solving the problem in the related art that the flux will melt through the seed crystal 500 when the seed crystal 500 is placed in the crucible, thereby achieving the simultaneous growth of multiple groups of silicon carbide crystals in a single furnace, and reducing the growth cost of silicon carbide crystals.

[0076] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method, characterized in that: include: A graphite crucible (100) for containing raw materials; A heating component (200) disposed around the graphite crucible (100) and used to heat the raw material in the crucible; A driving mechanism (300) disposed below the graphite crucible (100) and used to drive the graphite crucible (100) to rotate; A lifting and rotating mechanism (400) is arranged above the graphite crucible (100), and a bottom thereof is used to place a seed crystal (500) for crystal growth; Wherein, the graphite crucible (100) comprises: A crucible body (110) and a separation ring (120); The separation ring (120) is arranged in the crucible body (110) and is used to separate the crucible body (110) into concentric inner grooves (130) and outer grooves (140); The inner tank (130) is used to place Si blocks in the raw material; the outer tank (140) is used to place the solvent; The bottom of the inner tank (130) is provided with a mounting groove (131); When the crystal is growing, the seed crystal (500) is placed in the installation groove (131) and at the bottom of the lifting and rotating mechanism (400), respectively, and a plurality of silicon carbide crystals are grown simultaneously.

2. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 1, characterized in that: The crucible body (110) has a height H1; The height of the separation ring (120) is H2; Wherein, H1>H2, and the units of H1 and H2 are mm.

3. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 1, characterized in that: The radius of the inner groove (130) is R1; The radius of the outer groove (140) is R2; Among them, 1.5R1<R2<2R1, and the units of R1 and R2 are mm.

4. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 1, characterized in that: The depth of the mounting groove (131) is h; Among them, h<L, where L is the thickness of the seed crystal (500); Moreover, the range of h is between 0.5 mm and 1 mm.

5. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 1, characterized in that: The height of the bottom of the inner groove (130) is higher than the height of the bottom of the outer groove (140); When the driving mechanism (300) drives the graphite crucible (100) to rotate, the separation ring blocks the auxiliary solvent from entering the inner tank (130).

6. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 5, characterized in that: The outer tank (140) of the graphite crucible (100) is further provided with a plurality of stirring rods (141); A plurality of stirring rods (141) are arranged along the circumference of the outer tank (140) and connected to the bottom of the outer tank (140); When the driving mechanism (300) drives the graphite crucible (100) to rotate, the molten liquid in the outer tank (140) is stirred by the stirring rod (141).

7. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 6, characterized in that: The stirring rods (141) include multiple groups; The number of stirring rods (141) in each group of stirring rods (141) is two; A flow guide inclined plate (142) is provided between two stirring rods (141) in each group of stirring rods (141); Furthermore, the flow guiding direction of the flow guiding inclined plate (142) is opposite to the rotation direction of the graphite crucible (100).

8. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 7, characterized in that: The guide inclined plate (142) comprises a first curved plate (142a) and a second curved plate (142b); The outer arc side of the second arc-shaped plate (142b) is connected to the inner arc side of the first arc-shaped plate (142a); Furthermore, the second arc-shaped plate (142b) is arranged to be tilted downward, so as to guide the auxiliary solvent downward when the driving mechanism (300) drives the graphite crucible (100) to rotate, thereby facilitating the separation of melted carbon and auxiliary solvent.

9. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 7, characterized in that: The bottom of the guide inclined plate (142) is lower than the bottom of the inner groove (130); Furthermore, the top of the guide inclined plate (142) is lower than the top of the separation ring (120).

10. The device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method according to claim 7, characterized in that: The stirring rod (141) is threadedly connected to the bottom of the outer tank (140); Two stirring rods (141) in each group of stirring rods (141) are respectively provided with overlapping blocks (141a); A side wall of one of the overlapping blocks (141a) is provided with an overlapping groove (141b); One end of the guide inclined plate (142) is inserted into the overlapping groove (141b), and the other end is overlapped with another overlapping block (141a), and the outer side wall of the guide inclined plate (142) is in contact with the side wall of the outer groove (140); When the inclination angle a of the guide inclined plate (142) needs to be adjusted, the height of the overlap block (141a) is adjusted by screwing the corresponding stirring rod (141) to complete the adjustment of the inclination angle of the guide inclined plate (142).

11. A method for using the device for growing multiple groups of silicon carbide crystals in a single furnace by liquid phase method as claimed in claim 1, characterized in that: The method of use includes: The seed crystal (500) is bonded to the bottom of the lifting and rotating mechanism (400) and in the mounting groove (131) respectively; The Si block is placed in an inner tank (130) of a graphite crucible (100), and the auxiliary solvent is placed in an outer tank (140); Controlling the heating component (200) to heat the graphite crucible (100) until the flux is completely melted to obtain a melt; Controlling the driving mechanism (300) to drive the graphite crucible (100) to rotate; Adjusting the position of the high temperature line of the heating component (200) so that the high temperature line reaches the middle of the molten liquid in the inner tank; The lifting and rotating mechanism (400) is controlled to make the seed crystal (500) at the bottom of the lifting and rotating mechanism (400) contact the molten liquid, and the pulling and rotating mechanism (400) is continuously rotated, so that the bottom of the lifting and rotating mechanism (400) and the seed crystal (500) bonded in the installation groove (131) simultaneously grow crystals.

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