JP6187372B2 - Silicon carbide single crystal manufacturing equipment - Google Patents

Description

  The present invention relates to a silicon carbide (hereinafter referred to as SiC) single crystal manufacturing apparatus.

  Conventionally, as a SiC single crystal manufacturing apparatus for manufacturing a SiC single crystal by gas growth, for example, a manufacturing apparatus having a structure shown in Patent Document 1 has been proposed. In this conventional SiC single crystal manufacturing apparatus, a heating coil is disposed so as to surround a cylindrical vacuum container, and a gas heating container for thermally decomposing a raw material gas and an SiC single crystal growth space are provided inside the vacuum container. The reaction container which comprises is arrange | positioned. The gas heating vessel is formed in a hollow cylindrical shape, and a gas supply port is formed at the center position of the bottom surface and the top surface, and is configured so as to be able to supply the thermally decomposed source gas to the center portion of the growth surface of the SiC single crystal. Yes. The reaction vessel has a bottomed cylindrical shape opened at the bottom, and the upper surface side of the gas heating vessel is inserted into the opening.

  Furthermore, an outer peripheral wall is disposed so as to surround the outer periphery of the gas heating vessel and the crystal growth vessel, and a communication hole for gas discharge is formed at a position below the reaction vessel in the outer peripheral wall. As a result, the raw material gas introduced from the gas heating vessel into the reaction vessel is led to the communication hole in the outer peripheral wall through the space between the outer peripheral surface of the gas heating vessel and the inner peripheral surface of the reaction vessel, and is discharged to the outside through the communication hole. It is like that.

Japanese Patent No. 499965

  Since hydrogen is used when producing an SiC single crystal by gas growth, the graphite member provided in the SiC single crystal production apparatus is thermally etched, and long-term crystal growth cannot be performed. For this reason, in the conventional SiC single crystal manufacturing apparatus, the portion that becomes the path of the source gas in the gas heating vessel or reaction vessel that is heated is tantalum carbide that becomes a refractory metal carbide that does not melt even at the decomposition temperature of the SiC source gas ( TaC) coating is performed, and each container is made of tantalum carbide itself.

  However, even when tantalum carbide coating is performed, the area to be coated is large and the required amount of tantalum carbide increases, and when each container is formed of tantalum carbide itself, the required amount of tantalum carbide increases. In addition, it is difficult to form a tantalum carbide coating on the entire wall surface of a container having a complicated structure or to use tantalum carbide, which also increases manufacturing costs.

  An object of this invention is to provide the SiC single crystal manufacturing apparatus which can reduce the use area of a refractory metal carbide coat in view of the said point.

In order to achieve the above-mentioned object, in the invention according to claims 1 to 5, a crucible (10) configured in a cylindrical shape having a hollow portion, and a SiC single crystal (20) disposed in the hollow portion of the crucible, a pedestal (12) the seed crystal for growth (5) is placed, raw material decomposition chamber components that constitute the cracking chamber and introduced into the path of gas (3a) (7) and the discharge chamber of the unreacted gas of the material gas And a discharge chamber constituting part (8) constituting the discharge path, and a hollow part in the crucible, and the base is arranged by dividing the hollow part into a space in which the base is arranged and a space below the space. And a first support portion (9b) for supporting the decomposition chamber constituting portion and the discharge chamber constituting portion, a crucible, a decomposition chamber constituting portion, and a discharge chamber constituting portion. A heating device (14, 15) for heating the , Cracking chamber components and the discharge chamber forming portion is disposed in a lower position than the base of the crucible, and the cross-sectional area in the horizontal direction is smaller than the base, a portion corresponding to the growth space of the crucible The growth space side surface of the support portion and the inner wall surfaces of the decomposition chamber constituting portion and the discharge chamber constituting portion are formed of a refractory metal carbide or a refractory metal carbide.

  As described above, the inner wall surface of the decomposition chamber constituting portion, the discharge chamber constituting portion, the surface of the first support portion, and the portion constituting the SiC single crystal growth space in the crucible constituting the flow path of the source gas. Is coated with a refractory metal carbide. Alternatively, these portions are made of a refractory metal carbide. Thereby, it becomes possible to suppress the thermal etching of the graphite member in the flow path of the source gas, and it is possible to grow the SiC single crystal by the crystal growth for a long time.

  The portion coated with the refractory metal carbide or the portion formed with the refractory metal carbide is only part of the graphite member, specifically, the portion constituting the flow path of the source gas. For this reason, the surface area of the wall surface which comprises a gas inflow / outflow path | route can be made small. Therefore, the area of the portion coated with the refractory metal carbide can be reduced, the required amount of the refractory metal carbide can be reduced, and the manufacturing cost can be reduced.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a figure showing the section composition of SiC single crystal manufacturing device 1 concerning a 1st embodiment of the present invention. It is a figure which shows the cross-sectional structure of the SiC single crystal manufacturing apparatus 1 concerning 2nd Embodiment of this invention. It is a figure which shows the cross-sectional structure of the SiC single crystal manufacturing apparatus 1 concerning 3rd Embodiment of this invention. It is a figure which shows the cross-sectional structure of the SiC single crystal manufacturing apparatus 1 concerning 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
As shown in FIG. 1, the SiC single crystal manufacturing apparatus 1 supplies the source gas 3a from the source gas supply source 3 through the inlet 2 provided at the bottom, and is provided separately from the inlet 2 at the bottom. Unreacted gas in the raw material gas 3 a is discharged through the outlet 4. Then, the SiC single crystal manufacturing apparatus 1 forms an ingot of the SiC single crystal 20 by growing the SiC single crystal 20 on the seed crystal 5 made of the SiC single crystal substrate disposed in the apparatus.

  The SiC single crystal manufacturing apparatus 1 includes a source gas supply source 3, a vacuum vessel 6, a decomposition chamber component 7, a discharge chamber component 8, supports 9a and 9b, a crucible 10, a heat insulating material 11, a pedestal 12, and a rotating pull-up A mechanism 13 and first and second heating devices 14 and 15 are provided.

  The source gas supply source 3 supplies an SiC source gas 3 a containing Si and C together with a carrier gas (for example, a mixed gas of a silane-based gas such as silane and a hydrocarbon-based gas such as propane) from the inlet 2.

  The vacuum vessel 6 is made of quartz glass or the like, has a hollow cylindrical shape, can introduce and lead the carrier gas and the source gas 3a, and accommodates other components of the SiC single crystal manufacturing apparatus 1. The structure is such that the internal space in which it is housed can be depressurized by evacuating it. At the bottom of the vacuum vessel 6, there are provided an inlet 2 for the source gas 3a and an outlet 4 from which unreacted portions of the source gas 3a are discharged.

  The decomposition chamber constituting portion 7 and the discharge chamber constituting portion 8 are constituted by a cylindrical member whose both ends are supported by disk-like support portions 9a and 9b. The decomposition chamber constituting part 7 constitutes a decomposition chamber in which the raw material gas 3a is thermally decomposed and constitutes an introduction path for the raw material gas 3a. The discharge chamber constituting unit 8 constitutes a discharge chamber and a discharge path for discharging the unreacted gas in the raw material gas 3a to the outside of the SiC single crystal manufacturing apparatus 1.

  Both the decomposition chamber component 7 and the discharge chamber component 8 are arranged at a position separated from the central axis of the vacuum vessel 6, that is, a rotation central axis of a pedestal 12 described later, and have a smaller diameter than the pedestal 12. That is, the horizontal sectional area is reduced. In the case of this embodiment, the disassembly chamber component 7 and the discharge chamber component 8 are separated from each other by a predetermined distance at symmetrical positions with the center axes sandwiching the rotation center axis of the pedestal 12, and are configured with the same diameter. . The decomposition chamber constituting portion 7 and the discharge chamber constituting portion 8 are composed of, for example, graphite whose inner wall surface is coated with a refractory metal carbide such as TaC (tantalum carbide) or NbC (niobium carbide), or the whole is made of a refractory metal carbide. Has been. Here, the high melting point metal carbide means a metal carbide that does not melt even at a temperature (for example, about 2300 ° C.) used for the growth of the SiC single crystal 20.

  The support portions 9 a and 9 b are provided in the hollow portion of the crucible 10 so as to be divided into two vertically. One support portion 9 a corresponds to the second support portion and is disposed at the lower end of the crucible 10. The other support portion 9b corresponds to the first support portion, and is a space where the pedestal 12 is arranged by dividing the hollow portion into a space where the pedestal 12 is arranged and a space below the space. A growth space 10a of SiC single crystal 20 is formed. The support portions 9a and 9b are disk-shaped as described above, and circular holes are formed at positions corresponding to the decomposition chamber constituting portion 7 and the discharge chamber constituting portion 8, and the decomposition chamber constituting portions are formed in the respective circular holes. 7 and the discharge chamber component 8 are connected. The outer diameters of the support portions 9a and 9b are made to coincide with the inner diameter of the crucible 10 formed in a cylindrical shape as will be described later, and the support portions 9a and 9b are in close contact with each other on the inner wall surface of the crucible 10. The support portions 9a and 9b are made of graphite or the like, and only the surface on the pedestal 12 side of the support portion 9b located on the pedestal 12 side of the support portions 9a and 9b is TaC (tantalum carbide) or NbC (niobium carbide). ) And other high melting point metal carbides. Or only the support part 9b is comprised with the refractory metal carbide.

  The crucible 10 is a part constituting a reaction vessel constituted by a cylindrical member, and is arranged coaxially with the central axis of the vacuum vessel 6. The decomposition chamber constituting portion 7, the discharge chamber constituting portion 8, and the support portions 9a and 9b are disposed at a lower position in the hollow portion of the crucible 10, and a pedestal 12 is disposed at a position higher than that. Then, the SiC single crystal 20 is crystal-grown using the space formed between the support portion 9b and the pedestal 12 in the crucible 10 as the growth space 10a. The crucible 10 is also made of graphite, but only the inner wall surface of the portion constituting the growth space 10a, that is, the portion that is higher in temperature than the growth surface of the SiC single crystal 20, is TaC (tantalum carbide) or NbC (niobium carbide). It is coated with a refractory metal carbide such as. Or only the part which comprises the growth space 10a among the crucible 10 is comprised with a refractory metal carbide, and the upper part and the lower part are comprised with graphite.

  Thus, the inner wall surface of the decomposition chamber constituting part 7 and the discharge chamber constituting part 8, the surface of the support part 9b and the inner wall surface of the crucible 10 constituting the growth space 10a are coated with a refractory metal carbide, The portion is made of a refractory metal carbide. For this reason, the thermal etching in the said part can be suppressed.

  The second heat insulating material 11 constitutes an outer peripheral heat insulating material surrounding the outer periphery of the crucible 10 or the pedestal 12, is constituted by a cylindrical member, and is arranged coaxially with the central axis of the vacuum vessel 6. The second heat insulating material 11 is made of, for example, graphite.

  The pedestal 12 is configured by a plate-like member that is disposed coaxially with the central axis of the crucible 10. For example, the pedestal 12 is configured by graphite. Seed crystal 5 is affixed to the lower surface of pedestal 12, and SiC single crystal 20 is grown on the surface of seed crystal 5. The base 12 has a shape corresponding to the shape of the seed crystal 5 to be grown, for example, a disk shape. Further, the upper surface of the pedestal 12, that is, the surface opposite to the surface on which the seed crystal 5 is disposed, is connected to a pipe-like support shaft 13 a provided in the rotary pulling mechanism 13.

  The rotary pulling mechanism 13 rotates and pulls up the pedestal 12 via a pipe-like support shaft 13a. One end of the support shaft 13 a is connected to the surface of the pedestal 12 on the side opposite to the attaching surface of the seed crystal 5, and the other end is connected to the main body of the rotary pulling mechanism 13. The support shaft 13a is also made of graphite, for example. With such a configuration, the pedestal 12, the seed crystal 5 and the SiC single crystal 20 can be rotated and pulled together with the support shaft 13a, and the growth surface of the SiC single crystal 20 has a desired temperature distribution. The growth surface temperature can always be adjusted to a temperature suitable for growth.

Further, the wall surface of the support shaft 13a is provided with at least one gas introduction hole 13b, and a purge gas containing an inert gas such as Ar or an etching gas such as H ₂ can be introduced through the gas introduction hole 13b. ing.

  The first and second heating devices 14 and 15 are constituted by heating coils (induction heating coils and direct heating coils), and are arranged to surround the vacuum vessel 6. In the case of this embodiment, the 1st, 2nd heating apparatuses 14 and 15 are comprised by the coil for induction heating. The first and second heating devices 14 and 15 are configured to be able to independently control the temperature, and the first heating device 14 is disposed at a position corresponding to the lower side of the crucible 10, and the second heating device 15 is arranged at a position corresponding to the arrangement place of the base 12 above the crucible 10. Therefore, the temperature of the lower part of the crucible 10 can be controlled by the first heating device 14, and the temperature around the pedestal 12, the seed crystal 5 and the SiC single crystal 20 can be controlled by the second heating device 15.

  With this structure, the SiC single crystal manufacturing apparatus 1 according to the present embodiment is configured. Then, the manufacturing method of the SiC single crystal 20 using the SiC single crystal manufacturing apparatus 1 concerning this embodiment is demonstrated.

  First, the seed crystal 5 is attached to the pedestal 12 and installed in the crucible 10. And the 1st, 2nd heating apparatuses 14 and 15 are controlled and desired temperature distribution is attached. That is, the temperature at which the sublimation rate is higher than the recrystallization rate in other parts of the crucible 10 while the SiC single crystal 20 grows by recrystallization of the source gas 3a on the surface of the seed crystal 5. To be.

In addition, while bringing the vacuum vessel 6 to a desired pressure, a carrier gas containing an inert gas such as Ar or He or an etching gas such as H ₂ or HCl is introduced into the decomposition chamber component 7 from the inlet 2 as necessary. The source gas 3a is introduced. As a result, the source gas 3a flows as indicated by the arrows in FIG. 1, is thermally decomposed in the heated decomposition chamber constituting section 7 and then supplied to the seed crystal 5, and SiC is deposited on the surface of the seed crystal 5. A single crystal 20 is grown. Further, the unreacted gas in the raw material gas 3 a is discharged from the outlet 4 to the outside of the SiC single crystal manufacturing apparatus 1 through the discharge chamber constituting portion 8. The base 12, the seed crystal 5, and the SiC single crystal 20 are rotated by the rotary pulling mechanism 13 through the support shaft 13 a while being pulled up according to the growth rate of the SiC single crystal 20. Thereby, the height of the growth surface of the SiC single crystal 20 is kept substantially constant, and the temperature distribution of the growth surface temperature can be controlled with good controllability, so that the SiC single crystal 20 is grown with good crystallinity. Is possible.

  In addition, the decomposition chamber component 7 for introducing the raw material gas 3a is arranged at a predetermined distance from the rotation center axis of the pedestal 12, and the SiC single crystal 20 is rotated while the pedestal 12 is rotated by the rotary pulling mechanism 13. Since it is grown, the source gas 3a is uniformly supplied to the growth surface of the SiC single crystal 20. Therefore, SiC single crystal 20 can be grown at a uniform growth rate in the plane.

At this time, because it contains the etching gas such as H ₂ in a carrier gas is flowed together with the raw material gas 3a, made of graphite member during flow path of the raw material gas 3a from being thermally etched when exposed. However, the portion constituting the growth space 10a of the SiC single crystal 20 in the surface of the decomposition chamber constituting portion 7, the discharge chamber constituting portion 8, the support portion 9b and the crucible 10 constituting the flow path of the source gas 3a. Is coated with a refractory metal carbide. Alternatively, these portions are made of a refractory metal carbide. For this reason, it becomes possible to suppress that these surfaces are thermally etched.

Further, since a purge gas such as Ar or H ₂ is introduced through the gas introduction hole 13 b formed in the wall surface of the support shaft 13 a, the source gas 3 a does not flow above the pedestal 12, and is higher than the pedestal 12. It can suppress that a SiC polycrystal is produced | generated in the part used as a comparatively low temperature.

  As described above, in the SiC single crystal manufacturing apparatus 1 according to the present embodiment, the decomposition chamber constituting portion 7, the discharge chamber constituting portion 8, the surface of the support portion 9b, and the crucible 10 constituting the flow path of the source gas 3a. The inner wall surface of the portion constituting the growth space 10a of the SiC single crystal 20 is coated with a refractory metal carbide. Alternatively, these portions are made of a refractory metal carbide. As a result, thermal etching of the graphite member in the flow path of the source gas 3a can be suppressed, and the SiC single crystal 20 can be grown by crystal growth for a long time.

  The portion coated with the refractory metal carbide or the portion composed of the refractory metal carbide is a part of the graphite member, specifically, only the portion constituting the flow path of the raw material gas 3a. Therefore, as in Patent Document 1, the gas heating vessel corresponding to the decomposition chamber is made larger than the surface area of the growth surface of the grown crystal, or the crystal growth vessel is formed so as to surround the outer periphery of the gas heating vessel, and the discharge path is formed. Compared with the case where it comprises, the surface area of the wall surface which comprises a gas inflow / outflow path | route can be made small. Therefore, the area of the portion coated with the refractory metal carbide can be reduced, the required amount of the refractory metal carbide can be reduced, and the manufacturing cost can be reduced.

  Further, the decomposition chamber constituting part 7 and the discharge chamber constituting part 8 constituting the flow path of the raw material gas 3a coated with the refractory metal carbide are made smaller in diameter than the pedestal 12, that is, the horizontal sectional area is grown. The surface area of the growth surface of the SiC single crystal 20 is smaller. For this reason, the area of the part coated with the refractory metal carbide can be reduced, the required amount of the refractory metal carbide can be reduced, and the manufacturing cost can be reduced. Furthermore, the decomposition chamber component 7, the discharge chamber component 8, and the like can be configured only with a refractory metal carbide, instead of being coated with a refractory metal carbide on the surface of graphite. However, the same effect as described above can be obtained.

(Second Embodiment)
A second embodiment of the present invention will be described. The present embodiment is obtained by changing the configuration of the decomposition chamber constituting unit 7, the discharge chamber constituting unit 8, and the like with respect to the first embodiment, and is otherwise the same as the first embodiment, and therefore the first embodiment. Only different parts will be described.

  As shown in FIG. 2, in this embodiment, the intermediate heat insulating material 16 is arrange | positioned between the support parts 9a and 9b. The intermediate heat insulating material 16 insulates between the support part 9a side and the support part 9b side, makes the support part 9b side (growth space 10a side) high temperature, and if it leaves | separates from the growth space 10a, it will be low temperature from the temperature in the growth space 10a. To be. Specifically, the intermediate heat insulating material 16 has a circular hole formed at a position corresponding to the decomposition chamber component 7 and the discharge chamber component 8, and the decomposition chamber component 7 and the discharge chamber component 8 are formed in each circular hole. Is inserted.

  The decomposition chamber component 7 is extended to the support portion 9a located below, and only the upper inner wall surface from the intermediate heat insulating material 16 is coated with refractory metal carbide, or by refractory metal carbide. It is configured. The discharge chamber constituting portion 8 is formed only between the intermediate heat insulating material 16 and the support portion 9b, and has an inner wall surface coated with a refractory metal carbide or a refractory metal carbide. Further, a discharge space 17 having a horizontal cross-sectional area wider than that of the discharge chamber constituting portion 8 is formed below the intermediate heat insulating material 16, and the unreacted gas in the raw material gas 3a is more easily discharged. It is supposed to be.

  Thus, in order to reduce the portion of the decomposition chamber component 7 and the discharge chamber component 8 where the inner wall surface is coated with the refractory metal carbide or the portion formed of the refractory metal carbide, the support portion 9a, You may make it arrange | position the intermediate heat insulating material 16 between 9b. Thereby, the required amount of refractory metal carbide can be reduced, and the manufacturing cost can be further reduced.

  Further, the discharge chamber constituting portion 8 is formed from the growth space 10 a to the position of the intermediate heat insulating material 16, and a discharge space 17 having a horizontal sectional area wider than that of the discharge chamber constituting portion 8 is formed below the discharge chamber constituting portion 8. I try to do it. Since the temperature is gradually lowered when leaving the growth space 10a, there is a possibility that SiC polycrystal is generated. However, since the cross-sectional area of the discharge chamber constituting portion 8 is reduced, the discharge opening constituting portion 8 is moved to. There is a possibility of clogging due to adhesion of SiC polycrystal. However, if the discharge chamber constituting portion 8 is shortened to form the discharge space 17 as in the present embodiment, even if the SiC polycrystal is generated, the discharge chamber constituting portion 8 is blocked by the SiC polycrystal. It becomes possible to suppress being done.

(Third embodiment)
A third embodiment of the present invention will be described. The present embodiment is also obtained by changing the configuration of the decomposition chamber constituting unit 7, the discharge chamber constituting unit 8, and the like with respect to the first embodiment, and is otherwise the same as the first embodiment, and therefore the first embodiment. Only different parts will be described.

  As shown in FIG. 3, in this embodiment, the diameter of the discharge chamber constituting portion 8 is made larger than that of the decomposition chamber constituting portion 7, and the decomposition chamber constituting portion 7 and the discharge chamber constituting portion 8 are arranged coaxially, that is, the decomposition chamber. The discharge chamber constituting part 8 is arranged so as to surround the outer periphery of the constituting part 7. Thus, a discharge chamber is configured around the decomposition chamber. Thus, the discharge chamber may be arranged so as to surround the outer periphery of the decomposition chamber.

(Fourth embodiment)
A fourth embodiment of the present invention will be described. This embodiment is also a modification of the configuration of the decomposition chamber constituting portion 7, the discharge chamber constituting portion 8, the support portion 9b and the like with respect to the first embodiment, and the other is the same as the first embodiment, Only parts different from the first embodiment will be described.

  As shown in FIG. 4, in the present embodiment, the support portion 9 b has a tapered shape in which the inner diameter gradually increases from the bottom to the top, that is, from the decomposition chamber constituting portion 7 toward the pedestal 12 side. Thereby, the diameter becomes larger as the growth space 10a is directed upward.

  Moreover, about the decomposition chamber structure part 7 and the discharge chamber structure part 8, similarly to 3rd Embodiment, the diameter of the discharge chamber structure part 8 is made larger than the decomposition chamber structure part 7, and the decomposition chamber structure part 7 and the discharge chamber structure The discharge chamber constituting portion 8 is arranged so that the portion 8 is coaxially arranged, that is, surrounds the outer periphery of the decomposition chamber constituting portion 7. Thus, a discharge chamber is configured around the decomposition chamber.

  Further, as in the second embodiment, the intermediate heat insulating material 16 is disposed between the support portions 9a and 9b, and the support portion 9b side is insulated by insulating the space between the support portion 9a side and the support portion 9b side. The structure is such that the temperature is high and the temperature in the growth space 10a is lower than the temperature in the growth space 10a when separated from the growth space 10a. Specifically, the intermediate heat insulating material 16 has a circular hole formed at a position corresponding to the discharge chamber constituting portion 8, and the discharge chamber constituting portion 8 is inserted through the circular hole. The decomposition chamber component 7 is extended to the support portion 9a located below, and only the upper inner wall surface from the intermediate heat insulating material 16 is coated with refractory metal carbide, or by refractory metal carbide. It is configured. The discharge chamber constituting portion 8 is formed only between the intermediate heat insulating material 16 and the support portion 9b, and has an inner wall surface coated with a refractory metal carbide or a refractory metal carbide. Further, a discharge space 17 having a horizontal cross-sectional area wider than that of the discharge chamber constituting portion 8 is formed below the intermediate heat insulating material 16, and the unreacted gas in the raw material gas 3a is more easily discharged. It is supposed to be.

  By setting it as such a structure, the effect demonstrated in 1st-3rd embodiment can be acquired. Further, by forming the support portion 9b in a tapered shape, it is not necessary to coat the inner wall surface of the crucible 10 with a refractory metal carbide, or it is possible to coat only a small area. Therefore, the required amount of the refractory metal carbide can be reduced, and the manufacturing cost can be reduced.

(Other embodiments)
The present invention is not limited to the embodiment described above, and can be appropriately changed within the scope described in the claims.

  For example, in the first and second embodiments, the decomposition chamber component 7 and the discharge chamber component 8 are both arranged at positions shifted from the rotation center axis of the pedestal 12. You may make it correspond on a central axis. In the first and second embodiments, the decomposition chamber constituting portion 7 and the discharge chamber constituting portion 8 may be configured to have different diameters instead of the same diameter. In the third embodiment as well, the disassembly chamber component 7 and the discharge chamber component 8 are arranged at positions shifted from the rotation center axis of the pedestal 12, but these center axes coincide with the rotation center axis of the pedestal 12. May be.

  Further, in each of the above embodiments, the crucible 10 has a cylindrical shape having a hollow portion, but is not limited to a cylindrical shape, and may be a cylindrical shape, a structure integrated with any of the support portions 9a and 9b, The structure may be divided into a plurality of parts. In this case, for example, the crucible 10 is divided into a lower part than the support part 9b and an upper part from the support part 9b, and the lower part is integrated with the support part 9a, while the upper part is integrated with the support part 9b. Also good.

  Moreover, it is good also as a structure which integrated the support parts 9a and 9b, the decomposition chamber structure part 7, the discharge chamber structure part 8, etc. by arbitrary combinations.

DESCRIPTION OF SYMBOLS 1 SiC single crystal manufacturing apparatus 5 Seed crystal 7 Decomposition chamber structural part 8 Discharge chamber structural part 9a, 9b Support part 10 Crucible 10a Growth space 12 Pedestal 14, 15 Heating device 16 Intermediate heat insulating material 17 Discharge space 20 SiC single crystal

Claims (5)

A crucible (10) configured in a cylindrical shape having a hollow portion;
A pedestal (12) disposed in the hollow portion of the crucible and provided with a seed crystal (5) for growing a silicon carbide single crystal (20);
Cracking chamber and cracking chamber components that constitute the introduction path (7) and the discharge chamber structure portion constituting the discharge chamber and the discharge path of the unreacted gas of the source gas of the raw material gas (3a) and (8),
Growth of the silicon carbide single crystal in the space where the pedestal is arranged by partitioning the hollow portion into a space where the pedestal is arranged and a space below the space, which is provided in the hollow portion of the crucible A first support portion (9b) that constitutes the space (10a) and supports the decomposition chamber component and the discharge chamber component;
A heating device (14, 15) for heating the crucible, the decomposition chamber component, and the discharge chamber component;
The decomposition chamber component and the discharge chamber component are disposed at a lower position than the pedestal in the crucible, and a horizontal cross-sectional area is smaller than the pedestal.
The portion of the crucible corresponding to the growth space, the surface on the growth space side of the first support portion, and the inner wall surfaces of the decomposition chamber constituting portion and the discharge chamber constituting portion are coated or coated with a high melting point metal carbide. A silicon carbide single crystal manufacturing apparatus comprising a melting point metal carbide.   The crucible is formed to be lower than the first support portion, and an intermediate heat insulating material (16) is provided in a hollow portion of the crucible at a position below the first support portion, The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein heat insulation is performed between the growth space side of the hollow portion and a portion below the intermediate heat insulating material.   Of the decomposition chamber component, only the portion above the intermediate heat insulating material is made of a coating with a refractory metal carbide or a refractory metal carbide, and below the intermediate heat insulating material is made of graphite. The silicon carbide single crystal manufacturing apparatus according to claim 2. Of the hollow portion in the crucible, provided below the intermediate heat insulating material, has a second support portion (9a) that supports the decomposition chamber constituting portion together with the first support portion,
The discharge chamber constituent part is provided between the first support part and the intermediate heat insulating material, and the discharge chamber constituent part is not provided below the intermediate heat insulating material, whereby the intermediate heat insulating material and the second heat insulating material are provided. The silicon carbide single crystal manufacturing apparatus according to claim 3, wherein a discharge space (17) having a cross-sectional area larger than that of the discharge chamber constituting portion in the horizontal direction is formed between the support portion and the support portion.   5. The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein the discharge chamber constituting portion is provided so as to surround an outer periphery of the decomposition chamber constituting portion.

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