JP2009051701A - Apparatus and method for producing silicon carbide single crystal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a long high-quality SiC single crystal. <P>SOLUTION: A graphite crucible 1 is arranged such that a central axis R2 of the graphite crucible 1 is shifted by a certain distance L relative to a central axis R1 of a rotating device 5 or a heating device 6, and a region 4b in which screw dislocation can occur in a SiC single crystal substrate 3 is in agreement with the central axis R1 of the rotating device 5 and the heating device 6. Thereby, when growing up a SiC single crystal 4 on the SiC single crystal substrate 3, it is possible to prevent that the region 4b in which screw dislocation can occur in the SiC single crystal 4 have a higher temperature than the region surrounding the above region. Thus, the growth of a long SiC single crystal 4 becomes possible, and it also becomes possible to obtain many high-quality crystals having a large diameter. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an apparatus for manufacturing a silicon carbide (hereinafter referred to as SiC) single crystal that can be used for a material such as a semiconductor or a light emitting diode, and a method for manufacturing the same.

  Conventionally, a sublimation recrystallization method has been widely used as a method for growing a SiC single crystal. This sublimation recrystallization method involves joining a seed crystal to a graphite pedestal placed in a graphite crucible, heating and sublimating the SiC raw material arranged at the bottom of the crucible, and supplying the sublimation gas to the seed crystal. To grow a SiC single crystal.

  As a method for producing an SiC single crystal using such a sublimation recrystallization method, for example, there are methods disclosed in Patent Documents 1 to 4.

  FIG. 2A is a cross-sectional view showing a state in which a SiC single crystal is grown by the technique disclosed in Patent Document 1. FIG. As shown in this figure, a dislocation control seed crystal J3 having a surface inclined at an angle of, for example, 8 ° from the {0001} plane is disposed on a pedestal J2 of the lid portion J1 of the crucible, and the surface of the dislocation control seed crystal J3. An SiC single crystal J4 is grown on the substrate. When such growth is performed, since the position of the c-plane facet J5 can be formed toward the end of the crystal at the initial stage of growth, the c-plane facet J5 can be accommodated in the screw dislocation generation possible region J6. A heterogeneous polymorph or a different orientation crystal does not occur in a desired single polymorph, for example, a 4H single polymorph or a 6H single polymorph SiC single crystal.

  In the technique disclosed in Patent Document 2, a SiC single crystal is formed on the surface of a 6H polymorphic off-angle seed crystal in which a large number of (0001) planes are formed stepwise, The closer to the outermost surface, that is, the amount of sublimation gas supplied is increased in proportion to the height of the growth step.

  In the method disclosed in Patent Document 3, a seed crystal substrate is disposed at a position deviated in one direction from the center of the lid of the reaction furnace, and a temperature gradient extends from one edge of the seed crystal to the other opposite edge. And nucleation is controlled mainly by step growth.

In the method disclosed in Patent Document 4, step-flow growth is realized by using a just-angle seed crystal and providing a low-temperature region at the center of the seed crystal to form an off-angle state substantially at the initial stage of growth. Thus, the generation of defects is suppressed by controlling the generation of growth nuclei.
Japanese Patent No. 3764462 JP-A-4-357824 JP-A-8-245299 Japanese Patent Laid-Open No. 11-278985

  However, in the method shown in Patent Document 1, when the SiC single crystal is grown to be long, the outer peripheral side of the SiC single crystal becomes relatively high with the growth, and as shown in FIG. The growth surface becomes a curved surface, and the c-plane facet J5 gradually moves inward, so that the c-plane facet J5 comes off the spiral dislocation generation possible region J6. Therefore, there is no growth step for inheriting the underlying polymorph, and there is a problem that different polymorphs and different orientation crystals are likely to be newly generated in the SiC single crystal J4. For this reason, the growth length of the SiC single crystal J4 is substantially limited. Therefore, in the method shown in Patent Document 1, since long growth is difficult, a large number of high-quality crystals having a large diameter cannot be obtained.

  In addition, in the method shown in Patent Document 2, since it is impossible to precisely control the temperature distribution, it is difficult to precisely control the amount of reaction gas in proportion to the height of the growth step. There is a possibility that nucleation may occur at any place, and nucleation cannot be completely controlled, and 3C polymorphism is mixed. Therefore, the method shown in Patent Document 2 cannot obtain high-quality crystals.

  In addition, the method shown in Patent Document 3 has a problem in that a growth step does not exist in the portion where the temperature is lowest, so that nucleation cannot be controlled, and there is a possibility that polymorphism different from the seed crystal may occur. . Further, since the SiC single crystal grows with a large temperature gradient (30 ° C.) in the radial direction, the shape of the SiC single crystal is large at a position close to the central axis of the crucible and small at a position away from it. Since the shape becomes large and large distortion occurs, many defects are generated. Therefore, high quality crystals cannot be obtained even by the technique shown in Patent Document 3.

  Further, in the method shown in Patent Document 4, since there is no step in the low temperature region as in Patent Document 3 described above, nucleation cannot be controlled, and polymorphism different from the seed crystal may occur. In addition, even if there is a step in the low temperature region by chance, as the growth amount increases, the heat radiation from the growth crystal becomes uniform in the plane, preventing the low temperature at the center and preventing the initial growth. The effect can only be obtained. For this reason, the quality of the crystal when the growth amount is increased is deteriorated. Therefore, even with the technique shown in Patent Document 4, it is impossible to grow a high quality crystal long.

  In view of the above points, an object of the present invention is to provide a SiC single crystal manufacturing apparatus and a manufacturing method thereof capable of growing a high-quality SiC single crystal long.

  To achieve the above object, in the present invention, a crucible body (1a) composed of a bottomed cylindrical member having a bottom and an opening, and a pedestal (1c) on which a SiC single crystal substrate (3) is disposed. A cylindrical crucible (1) having a lid (1b) for sealing the opening of the crucible body (1a), and a heating device (6) disposed on the outer periphery of the crucible (1) The SiC raw material (2) is disposed in the crucible main body (1a), and the pedestal (1c) is inclined by 1 ° or more and 15 ° or less from the {0001} plane as the SiC single crystal substrate (3). Is formed on the SiC single crystal (4) grown on the growth surface, and the screw dislocation generation region (4b) capable of generating screw dislocations (4a) at a higher density than the surroundings is provided in the {0001 } Vect of the normal vector of the surface projected onto the growth surface A seed crystal having an end portion in the offset direction, which is the direction of the steel, and in a region of 50% or less on the growth surface, and heating and sublimating the SiC raw material (2) by the heating device (6) In the SiC single crystal manufacturing apparatus for growing the SiC single crystal (4) on the SiC single crystal substrate (3), the crucible (1) has a pedestal (1c) with respect to the central axis (R1) of the heating apparatus (6). The crucible (1) passing through the center of the crucible (1) is arranged such that the central axis (R2) is shifted by a predetermined distance (L).

  Thus, the crucible (1) is arranged such that the central axis (R2) of the crucible (1) is shifted by a predetermined distance (L) with respect to the central axis (R1) of the heating device (6). In such a structure, if the region (4b) in which the screw dislocations can be generated in the SiC single crystal substrate (3) is aligned with the central axis (R1) of the heating device (6), the SiC single crystal substrate (3) is formed. When the SiC single crystal (4) is grown, it is possible to prevent the region (4b) in which the screw dislocation can be generated in the SiC single crystal (4) from becoming higher temperature than the surrounding region. In other words, in the region (4b) where the screw dislocation can be generated, the growth rate can be made relatively fast and the screw grows by spiral dislocation, so that it is possible to obtain a single polymorph by taking over the underlying polymorph. Become. As a result, the SiC single crystal (4) can be grown long, and a large number of high-quality crystals having a large diameter can be obtained.

  In this case, the predetermined distance (L) is such that the region (4b) where the screw dislocation can be generated is included in the range of the predetermined distance (L) around the central axis (R1) of the heating apparatus (6). It is desirable that it is larger than ½ of the width (D) of the spiral dislocation generation possible region (4b) in the radial direction of the central axis (R1). In addition, the width (D) of the screw dislocation generation possible region (4b) is the end portion in the offset direction which is the direction of the vector obtained by projecting the normal vector of the {0001} plane onto the growth surface of the screw dislocation generation possible region (4b). In addition, since there is the seed crystal in the region of 50% or less on the growth surface as described above, the relationship 2D ≦ Rs is established.

  The predetermined distance (L) is preferably smaller than ½ of the diameter (Rs) of the disc-shaped SiC single crystal substrate (4). By doing in this way, it can prevent that the center axis | shaft (R2) of a crucible (1) is separated too much from the center axis | shaft (R1) of a heating apparatus (6).

  Furthermore, a crucible (1) can be mounted, and a rotating device (5) that eccentrically rotates the crucible (1) with the central axis (R1) and the concentric axis of the heating device (6) as the rotation axis can be provided. By rotating the crucible (1) eccentrically by such a rotating device (5), the temperature distribution at the same distance from the central axis (R1) of the rotating device (5) and the heating device (6) can be made uniform. It becomes possible to plan.

  Although the case where the present invention is grasped as an apparatus for manufacturing an SiC semiconductor device has been described above, the present invention can also be grasped as a method for manufacturing an SiC semiconductor device. That is, the center axis (R2) of the crucible (1) passing through the center of the pedestal (1c) is shifted from the center axis (R1) of the heating device (6) by a predetermined distance (L), and the SiC single crystal substrate By placing the crucible (1) so that the region (4b) in which the screw dislocation can be generated is included in the range of the predetermined distance (L) with the center axis (R1) of the heating device (6) as the center, (4) The long growth of the single crystal (4) becomes possible, and a large number of high-quality crystals having a large diameter can be obtained.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing a state in which a SiC single crystal is grown using the crystal growth apparatus according to the present embodiment.

  As shown in FIG. 1, a cylindrical graphite crucible 1 is used as a container for a crystal growth apparatus. The graphite crucible 1 sublimates the SiC raw material powder (SiC raw material) 2 provided at the bottom of the graphite crucible 1 by heat treatment, and causes the SiC single crystal 4 to grow on the SiC single crystal substrate 3 as a seed crystal. Is.

  The graphite crucible 1 includes a bottomed cylindrical crucible body 1a having an open top surface and a disc-shaped lid 1b that closes the opening of the crucible body 1a. Further, with the portion protruding at the center of the lid 1b constituting the graphite crucible 1 as a pedestal 1c, the SiC single crystal substrate 3 is bonded onto the pedestal 1c via an adhesive (not shown). Pedestal 1c is formed in a cylindrical shape at the center of disc-shaped lid member 1b, and the diameter of pedestal 1c is substantially the same as that of SiC single crystal substrate 3 to be joined. This time, the diameter Rs of the base 1c and the diameter of the SiC single crystal substrate 3 are both 75 mm.

  The graphite crucible 1 is mounted on the rotating device 5. Specifically, the rotating device 5 rotates about a central axis R1 in the figure, and the central axis R2 of the graphite crucible 1 relative to the central axis R1 of the rotating device 5 (of the base 1c). The graphite crucible 1 is mounted so that the center and the center of the SiC single crystal substrate 3 are concentric with each other by a certain distance L. This constant distance L this time is 15 mm. For this reason, when the rotating device 5 is rotated, the graphite crucible 1 is configured to be rotated such that the central axis R2 of the graphite crucible 1 is eccentric with respect to the central axis R1 of the rotating device 5.

  Further, a heating device 6 such as a heater is provided outside the graphite crucible 1 so as to surround the outer periphery of the graphite crucible 1. The center of the heating device 6 is concentric with the central axis R1 of the rotating device 5, and is shifted from the central axis R1 of the graphite crucible 1 by a predetermined distance L. By controlling the power of the heating device 6 arranged in this way, the temperature in the graphite crucible 1 can be controlled. For example, when the SiC single crystal 4 is grown, the temperature of the SiC single crystal substrate 3 as a seed crystal is lowered by about 100 ° C. from the temperature of the SiC raw material powder 2 by adjusting the power of the heating device 6. Can be kept. Although not shown, the graphite crucible 1 and the rotating device 5 are accommodated in a vacuum vessel into which argon gas can be introduced, and can be heated in this vacuum vessel.

  An SiC single crystal manufacturing process using the crystal growth apparatus configured as described above will be described.

  First, the SiC raw material powder 2 is placed in the crucible main body 1a of the graphite crucible 1, and the SiC single crystal substrate 3 that is a seed crystal is attached to the base 1c of the lid 1b via an adhesive or the like. At this time, the SiC single crystal substrate 3 is the same as the seed crystal (dislocation control seed crystal) shown in Patent Document 1 described above, that is, a plane inclined by 1 ° or more and 15 ° or less from the {0001} plane. A normal vector of the {0001} plane is projected onto the growth plane, which is a growth plane and has a screw dislocation generation region 4b in which the screw dislocations 4a can be generated in the growing SiC single crystal 4 at a higher density than the surroundings. A seed crystal having an end portion in an offset direction which is a vector direction and having a region of 50% or less on the growth surface is prepared.

  Here, the reason why the angle is set to 1 ° or more from the {0001} plane is that the surface where the screw dislocation generation region 4b is being grown in the c-axis direction or the direction perpendicular to the growth surface (hereinafter referred to as “below”) This is because it may be difficult to grow the SiC single crystal 4 so that the region projected onto the intermediate surface) and the c-plane facet 4c overlap. Further, the reason why the angle is set to 15 ° or less from the {0001} plane is that the SiC single crystal 4 must be grown high in the c-axis direction in order to eliminate stacking faults on the plane inclined more than 15 °. Because. In this case, a 4H single polymorphic SiC seed crystal 3 inclined by 8 ° from the {0001} plane is prepared.

  Then, the crucible body 1 a is closed with the lid member 1 b, and the graphite crucible 1 made in this way is mounted on the rotating device 5. At this time, the graphite crucible 1 is mounted such that the central axis R2 of the graphite crucible 1 is shifted by a certain distance L with respect to the central axis R1 of the rotating device 5, and the spiral dislocation generation possible region 4b in the SiC single crystal substrate 3 is provided. Specifically, the spiral dislocation generation possible region 4b is included in a range of a predetermined distance L around the central axis R1 of the heating device 6 so as to coincide with the central axis R1 of the rotating device 5 and the heating device 6. . In other words, when the graphite crucible 1 is eccentrically rotated, the trajectory through which the central axis R2 of the graphite crucible 1 passes includes the substantially all regions 4b where screw dislocations can be generated on the surface of the SiC single crystal substrate 3. The graphite crucible 1 is mounted on the rotating device 5 in alignment.

  Here, the predetermined distance L is a value determined by the relationship between the diameter Rs of the SiC single crystal substrate 3 and the width D of the screw dislocation generation region 4b, and is equal to or less than 1/2 of the diameter Rs and 1 / of the width D. 2 or more. By doing so, the entire region including the screw dislocation generation possible region 4b on the surface of the SiC single crystal substrate 3 is included in the trajectory through which the central axis R2 of the graphite crucible 1 passes when the graphite crucible 1 is eccentrically rotated. In addition, the central axis R2 of the graphite crucible 1 can be prevented from being too far from the central axis R1 of the rotating device 5 and the heating device 6. In this case, as described above, since L = 15 mm, Rs = 75 mm, and the width D of the screw dislocation generation region 4b is 25 mm, the relationship of 1 / 2D <L <1 / 2Rs and 2D ≦ Rs is satisfied. .

  Thereafter, after the inside of the vacuum vessel (not shown) is made an argon gas atmosphere, the temperature of the SiC raw material powder 2 is heated to 2000 to 2500 ° C. by the heating device 6, and the SiC single crystal substrate 3 is adjusted by adjusting the heating device 6. A temperature gradient is provided in the graphite crucible 1 so that the temperature of is lower than the temperature of the SiC raw material powder 2. At this time, the center position of the heating device 6 is the farthest distance from the heating device 6, so that the structurally dislocation-producible region 4 b of the surface of the SiC single crystal substrate 3 is structurally compared with other regions. And it becomes low temperature.

  Next, by adjusting the degree of vacuum of the vacuum device, the pressure in the graphite crucible 1 is set to 13.3 Pa to 26.7 kPa, and when sublimation growth is started, the SiC raw material powder 2 is sublimated to become sublimation gas, and SiC. The SiC single crystal 4 grows on the surface of the SiC single crystal substrate 3 that reaches the single crystal 4 and is at a relatively lower temperature than the SiC raw material powder 2 side.

  Thereafter, the SiC single crystal 4 is grown while making the amount of reduction of the SiC raw material powder 2 substantially constant. For example, the temperature distribution in the graphite crucible 1 can be adjusted by adjusting the power of the heating device 6. By doing so, the silicon / carbon ratio in the crucible 1 can be stabilized, and the SiC single crystal 4 can be grown long.

  At this time, as described above, the structurally possible region 4b of the screw dislocations in the surface of the SiC single crystal substrate 3 has a lower temperature than other regions, so that when the SiC single crystal 4 grows, It can be prevented that the region 4b in which the screw dislocation can be generated in the SiC single crystal 4 becomes higher in temperature than the surrounding region. For this reason, as shown in FIG. 1, the locus of the c-plane facet 4c extends substantially along the growth direction of the SiC single crystal 4, and the c-plane facet 4c is included in the screw dislocation generation possible region 4b. It becomes a state. That is, in the outer peripheral portion of the SiC single crystal 4 including the region 4b where the screw dislocation can be generated in the SiC single crystal 4, the growth surface becomes a curved surface as in the conventional case, so that the c-plane facet 4c gradually moves inward. It is possible to prevent the phenomenon that the c-plane facet 4cJ5 is detached from the spiral dislocation generation possible region 4b.

  Therefore, a growth step for inheriting the underlying polymorph can be secured, and it is possible to prevent the heterogeneous polymorph and different orientation crystal from being easily generated in the SiC single crystal 4. For this reason, the SiC single crystal 4 can be grown long, and a large number of high-quality crystals can be obtained. This time, the 4H single polymorphic SiC single crystal 4 can be grown in a diameter of 45 mm and a diameter of φ90 mm, and the screw dislocation generation region 4 b is removed based on the following formula to obtain a diameter of φ50 to φ65 mm. It becomes possible to obtain a large number of high-quality SiC single crystal 4 wafers.

(Equation 1)
75−25 = 50 ((diameter size of SiC single crystal substrate 3) − (width D of spiral dislocation generation region 4b) = (diameter size of high quality portion of SiC single crystal 4))
(Equation 2)
90−25 = 65 ((Diameter size of SiC single crystal 4) − (Width D of spiral dislocation generation possible region 4b) = (Diameter size of high quality portion of SiC single crystal 4))
As described above, in the present embodiment, the graphite crucible 1 is disposed so that the central axis R2 of the graphite crucible 1 is shifted by a certain distance L with respect to the central axis R1 of the rotating device 5 and the heating device 6, and SiC A region 4 b where the screw dislocation can be generated in the single crystal substrate 3 is made to coincide with the central axis R 1 of the rotating device 5 and the heating device 6. For this reason, when the SiC single crystal 4 is grown on the SiC single crystal substrate 3, it is possible to prevent the region 4 b in which the screw dislocations can be generated in the SiC single crystal 4 from becoming higher temperature than the surrounding region. As a result, the SiC single crystal 4 can be grown long, and a large number of high-quality crystals can be obtained.

(Second Embodiment)
A second embodiment of the present invention will be described. In this embodiment, the size of the SiC single crystal manufacturing apparatus is changed from that of the first embodiment. The other aspects are the same as those in the first embodiment, and only different parts will be described.

This time, the diameter Rs of the base 1c and the diameter of the SiC single crystal substrate 3 are both 75 mm,
The constant distance L is 15 mm, and the width D of the screw dislocation generation possible region 4b is 15 mm, and satisfies the relationship of 1 / 2D <L <1 / 2Rs and 2D ≦ Rs.

  With such a dimension, the 4H single polymorphic SiC single crystal 4 can grow to have a length of 45 mm and a diameter of φ90 mm, and based on the following formula, the screw dislocation generation region 4b is removed, It is also possible to obtain a large number of high-quality SiC single crystal 4 wafers having a diameter of φ60 to φ75 mm.

(Equation 3)
75-15 = 60 ((Diameter size of SiC single crystal substrate 3)-(Width D of spiral dislocation generation possible region 4b) = (Diameter size of high quality portion of SiC single crystal 4))
(Equation 4)
90-15 = 75 ((Diameter dimension of SiC single crystal 4)-(Width D of spiral dislocation generation possible region 4b) = (Diameter dimension of high quality portion of SiC single crystal 4))
Thus, even if the width D of the screw dislocation generation possible region 4b is reduced to 15 mm as compared with the first embodiment (the width D of the screw dislocation generation possible region 4b is equal to the {0001} plane of the screw dislocation generation possible region 4b. As described above, it is the end crystal in the offset direction which is the direction of the vector projected onto the growth plane and the seed crystal in the region of 50% or less on the growth plane. In short, it is more effective to increase the diameter of the high-quality portion of the SiC single crystal 4 by reducing the ratio of the screw dislocation generation possible region 4b.), SiC single crystal substrate 3, when the SiC single crystal 4 is grown, it is possible to prevent the region 4 b of the SiC single crystal 4 from generating a high temperature compared to the surrounding region. Therefore, the diameter of the high quality portion of the SiC single crystal 4 can be increased, and a large number of high quality crystals having a large diameter can be obtained.

(Other embodiments)
In the above embodiment, the graphite crucible 1 is taken as an example of the crucible, but this is merely an example, and not all of the crucible may be made of graphite. For example, the inner wall surface may be coated with Ta (tantalum) or the like.

  In the above embodiment, the graphite crucible 1 is rotated using the rotating device 5. However, in order to make the temperature distribution uniform at a location equidistant from the central axis R 1 of the rotating device 5 and the heating device 6. It is not always necessary to rotate.

  In the above-described embodiment, the width D of the screw dislocation generation region 4b is exemplified by two dimensions. However, not only the width D but also other dimensions are not limited to the above, and any values are applicable. Is possible. In addition, by setting the constant distance L to a large value and the width D of the screw dislocation generation possible region 4b to be as small as possible, a large-diameter crystal can be efficiently obtained. That is, when the SiC single crystal 4 is grown on the SiC single crystal substrate 3, the constant distance L is set to a large value that the spiral dislocation generation possible region 4b of the SiC single crystal 4 becomes higher in temperature than the surrounding region. It is because it makes it easy to prevent. By doing so, the growth rate can be relatively increased in the region (4b) where the screw dislocation can be generated, and the spiral growth is caused by the screw dislocation, so that the single polymorph can be obtained by taking over the underlying polymorph. It becomes possible.

It is a figure which shows the cross-sectional structure of the graphite crucible in 1st Embodiment of this invention. (A) is sectional drawing which showed a mode that the SiC single crystal was grown by the conventional method, (b) is a mode when the SiC single crystal was further grown long from the state of (a). It is sectional drawing shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Graphite crucible, 1a ... Main body, 1b ... Cover material, 1c ... Base, 2 ... SiC raw material powder,
3 ... single crystal substrate, 4 ... SiC single crystal, 5 ... rotating device, 6 ... heating device

Claims (5)

A crucible body (1a) composed of a bottomed cylindrical member having a bottom and an opening, and a pedestal (1c) on which a silicon carbide single crystal substrate (3) is disposed, the crucible body (1a) A cylindrical crucible (1) having a lid (1b) for sealing the opening, and a heating device (6) disposed on the outer periphery of the crucible (1),
The silicon carbide raw material (2) is disposed in the crucible body (1a), and the pedestal (1c) is inclined by 1 ° or more and 15 ° or less from the {0001} plane as the silicon carbide single crystal substrate (3). A screw dislocation generation possible region (4b) capable of generating screw dislocations (4a) at a higher density than the surroundings in the silicon carbide single crystal (4) having a surface as a growth surface and growing on the growth surface. Disposing a seed crystal having an end portion in an offset direction, which is a vector direction obtained by projecting a normal vector of the {0001} plane onto the growth plane, and having a region of 50% or less on the growth plane;
In the silicon carbide single crystal manufacturing apparatus for growing the silicon carbide single crystal (4) on the silicon carbide single crystal substrate (3) by heating and sublimating the silicon carbide raw material (2) with the heating device (6). ,
In the crucible (1), the central axis (R2) of the crucible (1) passing through the center of the pedestal (1c) is shifted from the central axis (R1) of the heating device (6) by a predetermined distance (L). An apparatus for producing a silicon carbide single crystal, wherein The heating device such that the predetermined distance (L) includes the region (4b) in which the screw dislocation can be generated within a range of the predetermined distance (L) around the central axis (R1) of the heating device (6). 2. The silicon carbide according to claim 1, wherein the silicon carbide is larger than ½ of a width (D) of the spiral dislocation generation possible region (4 b) in the radial direction of the central axis (R 1) of (6). Single crystal manufacturing equipment. The said predetermined distance (L) is smaller than 1/2 of the diameter (Rs) of the said disk-shaped silicon carbide single crystal substrate (4), The manufacturing apparatus of the silicon carbide single crystal of Claim 1 characterized by the above-mentioned. . The crucible (1) is mounted, and a rotating device (5) for rotating the crucible (1) eccentrically with a central axis (R1) and a concentric axis of the heating device (6) as rotation axes is provided. The apparatus for producing a silicon carbide single crystal according to any one of claims 1 to 3. A crucible body (1a) composed of a bottomed cylindrical member having a bottom and an opening, and a pedestal (1c) on which a silicon carbide single crystal substrate (3) is disposed, the crucible body (1a) A cylindrical crucible (1) having a lid (1b) for sealing the opening and a heating device (6) arranged on the outer periphery of the crucible (1) are prepared,
The silicon carbide raw material (2) is disposed in the crucible body (1a), and the pedestal (1c) is inclined by 1 ° or more and 15 ° or less from the {0001} plane as the silicon carbide single crystal substrate (3). A region (4b) capable of generating screw dislocations in a silicon carbide single crystal (4) having a surface as a growth surface and capable of generating screw dislocations (4a) at a higher density than the surroundings. Disposing a seed crystal having an end portion in an offset direction, which is a vector direction obtained by projecting a normal vector of the {0001} plane onto the growth plane, and having a region of 50% or less on the growth plane;
In the method for producing a silicon carbide single crystal, the silicon carbide single crystal (4) is grown on the silicon carbide single crystal substrate (3) by heating and sublimating the silicon carbide raw material (2) with the heating device (6). ,
The center axis (R2) of the crucible (1) passing through the center of the pedestal (1c) is shifted from the center axis (R1) of the heating device (6) by a predetermined distance (L), and the silicon carbide single unit The crucible (1) is placed so that the crystal dislocation generation possible region (4b) is included in the range of the predetermined distance (L) centering on the central axis (R1) of the heating device (6). A method for producing a silicon carbide single crystal comprising disposing the silicon carbide single crystal.

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