JP5381957B2 - Silicon carbide single crystal manufacturing apparatus and manufacturing method - Google Patents

Description

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

  2. Description of the Related Art Conventionally, SiC single crystal manufacturing apparatuses that perform SiC single crystal growth by a gas supply method are known. In this SiC single crystal manufacturing apparatus, a heating vessel (crucible) in which crystal growth of SiC single crystal is performed is arranged in a vacuum vessel, and SiC source gas is supplied into the heating vessel and power is supplied from an induction power source. Based on the induction heating based on the induction coil, a SiC single crystal is grown on the surface of the seed crystal disposed in or near the heating vessel.

  An apparatus for manufacturing such a SiC single crystal is disclosed in Patent Document 1. This SiC single crystal manufacturing apparatus has a structure in which the periphery of the heating container is surrounded by a cylindrical heat insulating material so that the temperature in the heating container can be controlled efficiently, and the heat insulating material is perpendicular to the axial direction. The structure is divided into two parts.

Japanese Examined Patent Publication No. 61-47686

  In the SiC single crystal manufacturing apparatus as described above, an induced current flows through the cylindrical heat insulating material due to induction overheating by the induction coil. As a method for suppressing this induced current, it is conceivable to form a structure in which the path of the induced current is blocked by inserting a split surface that divides the cylindrical heat insulating material in parallel to the central axis.

  However, since it is necessary to create a very high temperature atmosphere for growing a SiC single crystal, the power of the induction power source is very high and the induction current is also very large. For this reason, there is a problem that a local discharge phenomenon occurs in a relatively narrow portion of the gap between adjacent heat insulating materials divided on the dividing surface, and the stable supply of induced power is hindered. To do. In addition, spike current flows on the induction power supply side, and the function of the protection circuit provided in the power supply circuit of the induction power supply turns off the induction power supply, making it impossible to realize the high temperature necessary for the growth of the SiC single crystal. The problem also arises.

  In view of the above points, the present invention provides a SiC single crystal that can suppress the occurrence of a discharge phenomenon between adjacent divided heat insulating materials when the cylindrical heat insulating material is divided in parallel to the central axis. An object of the present invention is to provide a manufacturing apparatus and a manufacturing method.

  In order to achieve the above object, in the invention described in claim 1, the heating container (8) arranged on the upstream side of the flow path of the source gas (3) from the pedestal (9) and heats the source gas (3). A heating device (13, 14) for inductively heating the heating container (8), and a cylindrical outer peripheral heat insulating material (10) composed of graphite disposed around the outer periphery of the heating container (8). The outer peripheral heat insulating material (10) includes a plurality of divided portions (10a to 10c) divided by a dividing surface that is divided in a direction along the central axis of the outer peripheral heat insulating material (10), Combining the divided portions (10a to 10c) constitutes a cylindrical shape, and further comprises a material having a lower resistance than graphite constituting the outer peripheral heat insulating material (10), and connects the divided portions (10a to 10c). Adjacent divided parts (10a to 10c) by being fixed to the eyes Is characterized by low resistance member (20) is provided to be connected.

  As described above, the outer peripheral heat insulating material (10) is configured in a cylindrical shape, and has a configuration including the divided portions (10a to 10c) in which the cylindrical shape is divided into a plurality of portions parallel to the central axis, and each divided portion (10a). To 10c), a low resistance member (20) is provided so as to cover the joint portion. Thereby, it is possible to suppress a local discharge phenomenon from occurring in a portion having a relatively narrow width among the gaps between the plurality of divided portions (10a to 10c), and it is possible to stably supply the induced power. .

  In the invention according to claim 2, the low resistance member (20) has a cylindrical shape along the inner peripheral surface or outer peripheral surface of the outer peripheral heat insulating material (10), and the inner peripheral surface or outer peripheral surface of the outer peripheral heat insulating material (10). It is characterized by covering at least a part of.

  Thus, the low resistance member (20) can be arranged so as to cover at least a part of the inner peripheral surface or the outer peripheral surface of the cylindrical outer peripheral heat insulating material (10). In this way, the raw material gas (3) permeates the inner peripheral surface or the outer peripheral surface of the outer peripheral heat insulating material (10) in the portion covered with the low resistance member (20) while obtaining the effect of claim 1. It becomes possible to suppress precipitation of solid SiC by doing.

  In invention of Claim 3, a low resistance member (20) is made into the cylindrical shape along the inner peripheral surface or outer peripheral surface of an outer periphery heat insulating material (10), and the inner peripheral surface and outer peripheral surface of an outer peripheral heat insulating material (10). It is characterized by covering the whole area of at least one of the above.

  Thus, you may arrange | position the low resistance member (20) so that the inner peripheral surface of the cylindrical outer peripheral heat insulating material (10) or the whole outer peripheral surface may be covered. In this way, it is possible to suppress the precipitation of solid SiC due to the penetration of the raw material gas (3) into the inner peripheral surface or the outer peripheral surface of the outer peripheral heat insulating material (10) while obtaining the effect of claim 1. It becomes possible.

  In the invention according to claim 4, in the low resistance member (20), the raw material gas (3) flowing between the pedestal (9) and the heating vessel (8) in the outer peripheral heat insulating material (10) collides first. It is characterized by covering the position to perform.

  With such a configuration, the place where solid SiC is most likely to precipitate can be covered with the low-resistance member (20), so that it is possible to suppress the precipitation of solid SiC.

  The low resistance member (20) described here is made of, for example, a graphite sheet or a refractory metal carbide as described in claim 5.

  In the above claims 1 to 5, the case where the present invention is grasped as an invention of an apparatus for producing a SiC single crystal has been described. However, as described in claim 6, the present invention is grasped as a method for producing an SiC single crystal. You can also.

  Specifically, as described in claim 6, a cylinder is formed so as to surround the outer periphery of the heating vessel (8), with the hollow portion of the heating vessel (8) configured by a hollow cylindrical member as a gas supply path. The outer peripheral heat insulating material (10) having a shape is arranged, and the outer peripheral heat insulating material (10) is divided into a plurality of divided portions (10a) divided by a dividing surface that is divided in a direction along the central axis of the outer peripheral heat insulating material (10). -10c), and a plurality of divided portions (10a to 10c) are combined to form a cylindrical shape, and a plurality of divided portions (10a) constituting the outer peripheral heat insulating material (10) To 10c), the adjacent divided portions (10a to 10c) are fixed by fixing a low resistance member (20) made of a material having a lower resistance than graphite constituting the outer peripheral heat insulating material (10). Is connected, and in this state, add the heating container (8). Introducing the source gas (3) from one end side of the heating vessel (8) and deriving the source gas (3) from the other end side of the heating vessel (8) while induction heating with the apparatus (13, 14). By supplying to the seed crystal (5) and growing a silicon carbide single crystal, the same effect as in the first aspect 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.

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 the figure which showed the 1st outer periphery heat insulating material 10 and the low resistance member 20 which are shown in FIG. 1, (a) is a top view, (b) is a perspective view. It is the figure which showed the 1st outer periphery heat insulating material 10 and the low resistance member 20 with which the SiC single crystal manufacturing apparatus 1 concerning 2nd Embodiment of this invention is equipped, (a) is a top view, (b) is a perspective view. is there. 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 the figure which showed the 1st outer periphery heat insulating material 10 and the low resistance member 20 which are shown in FIG. 4, (a) is a top view, (b) is a perspective view. It is the figure which showed the 1st outer periphery heat insulating material 10 and the low resistance member 20 with which the SiC single crystal manufacturing apparatus 1 concerning 4th Embodiment of this invention is equipped, (a) is a top view, (b) is a perspective view. is there.

  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)
In FIG. 1, sectional drawing of the SiC single crystal manufacturing apparatus 1 of this embodiment is shown. Hereinafter, the structure of SiC single crystal manufacturing apparatus 1 will be described with reference to FIG.

  An SiC single crystal manufacturing apparatus 1 shown in FIG. 1 includes an SiC source gas 3 containing Si and C together with a carrier gas through an inlet 2 provided at the bottom (for example, a silane-based gas such as silane and a hydrocarbon such as propane). A SiC single crystal is grown on a seed crystal 5 made of a SiC single crystal substrate disposed in the SiC single crystal manufacturing apparatus 1 by supplying a gas (mixed gas of the system gas) and discharging it through the upper outlet 4 It is.

  The SiC single crystal production apparatus 1 includes a vacuum vessel 6, a first heat insulating material 7, a heating vessel 8, a pedestal 9, a first outer peripheral heat insulating material 10, a rotary pulling mechanism 11, a second outer peripheral heat insulating material 12, a first and a first Two heating devices 13 and 14 are provided.

  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 3, and houses 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. An inlet 2 for the source gas 3 is provided at the bottom of the vacuum vessel 6, and an outlet 4 for the source gas 3 is provided at the upper part (specifically, the position above the side wall).

  The first heat insulating material 7 has a cylindrical shape, is disposed coaxially with respect to the vacuum vessel 6, and constitutes a raw material gas introduction pipe 7 a with a hollow portion. The first heat insulating material 7 is made of, for example, graphite or graphite whose surface is coated with TaC (tantalum carbide).

  The heating vessel 8 constitutes a reaction chamber for growing a SiC single crystal on the surface of the seed crystal 5, and is made of, for example, graphite or graphite whose surface is coated with TaC (tantalum carbide), etc. The gas 3 is disposed on the upstream side of the flow path. By this heating container 8, the raw material gas 3 is decomposed while excluding particles contained in the raw material gas 3 until the raw material gas 3 supplied from the inlet 2 is led to the seed crystal 5.

  Specifically, the heating container 8 has a structure having a hollow cylindrical member, and in the case of the present embodiment, the heating container 8 is composed of a bottomed cylindrical member. The heating container 8 is provided with a gas introduction port 8a that communicates with the hollow portion of the first heat insulating material 7 at the bottom, and the source gas 3 that has passed through the hollow portion of the first heat insulating material 7 is heated through the gas introduction port 8a. It is introduced into the container 8.

  The pedestal 9 has, for example, a cylindrical shape, is disposed coaxially with the central axis of the heating container 8, and is made of, for example, graphite or graphite whose surface is coated with TaC (tantalum carbide). A seed crystal 5 having a diameter of the same dimension is attached to this pedestal 9, and an SiC single crystal is grown on the surface of the seed crystal 5.

  The first outer peripheral heat insulating material 10 guides the remainder of the raw material gas 3 guided to the pedestal 9 side to the outlet 4 side while surrounding the outer periphery of the heating container 8 and the pedestal 9. Specifically, the remainder of the source gas 3 after being supplied to the seed crystal 5 passes through the gap between the pedestal 9 and the first outer peripheral heat insulating material 10 and is led to the outlet 4. A low resistance member 20 described later is provided on the inner peripheral surface of the first outer peripheral heat insulating material 10. Detailed structures of the first outer peripheral heat insulating material 10 and the low resistance member 20 will be described later.

  The rotary pulling mechanism 11 rotates and pulls up the pipe material 11a. One end of the pipe material 11 a is connected to the surface of the base 9 opposite to the surface to which the seed crystal 5 is attached, and the other end is connected to the main body of the rotary pulling mechanism 11. With such a structure, the pedestal 9, the seed crystal 5 and the SiC single crystal can be rotated and pulled together with the pipe material 11a, and the growth surface of the SiC single crystal has a desired temperature distribution, while the SiC single crystal is grown. Along with this, the temperature of the growth surface can always be adjusted to a temperature suitable for growth. The pipe material 11a is also made of, for example, graphite or graphite whose surface is coated with TaC (tantalum carbide). Note that the pipe material 11a may be a simple rod-shaped member or the like as long as it serves as a rotating shaft or a pulling-up shaft.

  The 2nd outer periphery heat insulating material 12 is arrange | positioned along the side wall surface of the vacuum vessel 6, and has comprised the hollow cylinder shape. This 2nd outer periphery heat insulating material 12 and the 1st outer periphery heat insulating material 10 are arrange | positioned coaxially with the central axis of the heating container 8, and these are arrange | positioned concentrically. The second outer peripheral heat insulating material 12 substantially surrounds the first heat insulating material 7, the heating container 8, the pedestal 9, the first outer peripheral heat insulating material 10, and the like. The second outer peripheral heat insulating material 12 is also made of, for example, graphite or graphite whose surface is coated with TaC (tantalum carbide).

  The first and second heating devices 13 and 14 are constituted by induction heating coils for receiving the power supply from the induction power source driven by the power supply circuit and induction heating the heating vessel 8, and around the vacuum vessel 6. It is arranged to surround. These 1st, 2nd heating apparatuses 13 and 14 are comprised so that temperature control can be carried out independently, respectively. For this reason, finer temperature control can be performed. The first heating device 13 is disposed at a position corresponding to the heating container 8. The second heating device 14 is disposed at a position corresponding to the base 9. Due to this arrangement, the temperature distribution on the growth surface of the SiC single crystal can be adjusted to a temperature suitable for the growth of the SiC single crystal by controlling the first and second heating devices 13 and 14.

  Next, the detailed structure of the 1st outer periphery heat insulating material 10 and the low resistance member 20 is demonstrated. 2A and 2B are views showing the first outer peripheral heat insulating material 10 and the low-resistance member 20, in which FIG. 2A is a top view and FIG. 2B is a perspective view.

  As shown in FIG. 2, the 1st outer periphery heat insulating material 10 is carrying out the cylindrical shape, and is set as the structure provided with several division part 10a-10c divided by the division surface parallel to a central axis. The plurality of divided portions 10a to 10c are made of graphite having an electrical specific resistance of about several hundreds to 1000 mΩ · cm, such as graphite having a porous or fibrous structure. A cylindrical shape is configured by combining the plurality of divided portions 10a to 10c.

  Regarding the circumferential dimension of each divided portion 10a to 10c, in other words, the angle formed by the line drawn toward the divided portion of each divided portion 10a to 10c with the central axis as the center when the first outer peripheral heat insulating material 10 is viewed from the upper surface. May be different, but in the present embodiment, they have the same dimensions. Each divided surface has a stepped shape, the divided surfaces of the divided portions 10a to 10c mesh with each other, the inner peripheral surfaces and the outer peripheral surfaces of the divided portions 10a to 10c form a cylindrical surface, and have a predetermined thickness. This constitutes a cylindrical shape.

  Moreover, the low resistance member 20 is being fixed so that the location of the joint of each division | segmentation part 10a-10c among the 1st outer periphery heat insulating materials 10 may be covered. The low resistance member 20 is connected to the adjacent divided portions 10a to 10c by being fixed to a joint portion of the divided portions 10a to 10c directly or via an adhesive or the like. Further, the low resistance member 20 is made of a material having a lower relative efficiency than the graphite constituting the first outer peripheral heat insulating material 10. For example, the low resistance member 20 is made of a graphite sheet, a high melting point metal carbide such as TaC (tantalum carbide) or TiC (titanium carbide). In the case of a graphite sheet, it is composed of the same graphite as the divided portions 10a to 10c. However, there are graphites having various crystal structures, for example, a low ratio of 700 μΩ · m like Nika Film (registered trademark). What has resistance can be applied as the low resistance member 20.

  And about each thickness (diameter direction dimension) and specific resistance about each division | segmentation part 10a-10c and low resistance member 20 with which the 1st outer periphery heat insulating material 10 comprised in this way was established, the following relationship is materialized. Has been designed. That is, assuming that the thickness of the low resistance member 20 is t1, the thickness of each divided portion 10a to 10c is t2, the specific resistance of the low resistance member 20 is ρ1, and the specific resistance of each divided portion 10a to 10c is ρ2, t1 <t2. In addition, t1 · ρ1 <t2 · ρ2 is established.

  The SiC single crystal manufacturing apparatus 1 is configured by the structure as described above. Then, the manufacturing method of the SiC single crystal using the SiC single crystal manufacturing apparatus 1 comprised in this way is demonstrated.

  First, the first and second heating devices 13 and 14 are controlled to give a desired temperature distribution. That is, the source gas 3 is recrystallized on the surface of the seed crystal 5, so that the SiC single crystal grows and the sublimation rate becomes higher in the heating vessel 8 than the recrystallization rate. To do.

  Further, the raw material gas 3 is introduced through the raw material gas introduction pipe 7a while introducing a carrier gas or an etching gas such as hydrogen with an inert gas such as Ar gas as necessary while keeping the vacuum vessel 6 at a desired pressure. Thereby, as shown by the arrow in FIG. 1, the source gas 3 flows and is supplied to the seed crystal 5 so that a SiC single crystal can be grown.

  At this time, the heating container 8 is induction-heated based on the power supply to the induction heating coils constituting the first and second heating devices 13 and 14, but at this time, the first outer peripheral heat insulating material 10 is also used. An induced current flows. Although this induced current tends to flow in the circumferential direction of the first outer peripheral heat insulating material 10, as described above, the graphite portion of the first outer peripheral heat insulating material 10 is divided in the circumferential direction by the dividing portions 10a to 10c. For this reason, it becomes difficult for the air to flow due to a gap existing between the divided portions 10a to 10c. For this reason, it is possible to suppress the induced current.

  However, in such a configuration that is simply divided by the divided portions 10a to 10c, a local discharge phenomenon occurs in a relatively narrow portion of the gap between the divided portions 10a to 10c, and the induced power is stable. Supply can be hindered.

  On the other hand, in this embodiment, since the low resistance member 20 is provided so as to cover the joints of the divided portions 10a to 10c, an induced current flows around the low resistance member 20. Is allowed, and a discharge phenomenon can be prevented. Further, if the thickness of the low resistance member 20 is too thick, it may not be possible to suppress the induced current flowing in the first outer peripheral heat insulating material 10 as compared with the case where the low resistance member 20 is not provided. In the embodiment, t1 <t2 and t1 · ρ1 <t2 · ρ2 are established. For this reason, it is possible to allow the induced current to flow to some extent while appropriately suppressing the induced current. As a result, the occurrence of a local discharge phenomenon can be suppressed, and the induced power can be stably supplied.

  As described above, in the present embodiment, the first outer peripheral heat insulating material 10 is configured in a cylindrical shape, and has a configuration including the divided portions 10a to 10c that are divided into a plurality of cylindrical shapes parallel to the central axis, and It has the structure provided with the low resistance member 20 so that the location of the joint of each division | segmentation part 10a-10c may be covered. Thereby, it is possible to suppress a local discharge phenomenon from occurring in a relatively narrow portion of the gaps between the plurality of divided portions 10a to 10c, and it is possible to stably supply induced power.

(Second Embodiment)
A second embodiment of the present invention will be described. In the present embodiment, the configuration of the low-resistance member 20 is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only the parts different from the first embodiment will be described.

  FIG. 3 is a view showing the first outer peripheral heat insulating material 10 and the low-resistance member 20 provided in the SiC single crystal manufacturing apparatus 1 according to the present embodiment. FIG. 3 (a) is a top view, and FIG. 3 (b). Is a perspective view.

  As shown in FIG. 3, in this embodiment, the low resistance member 20 disposed on the inner peripheral surface side of the first outer peripheral heat insulating material 10 has a cylindrical shape along the inner peripheral surface, and the inner periphery of the first outer peripheral heat insulating material 10. The entire surface is covered with the low resistance member 20. The low resistance member 20 is fixed to at least each of the divided portions 10a to 10c directly or via an adhesive or the like, and the induced current flowing through the first outer peripheral heat insulating material 10 is at the joint of the divided portions 10a to 10c. It flows to the low resistance member 20. As for the material of the low resistance member 20, a material having a lower specific resistance and lower gas permeability than graphite constituting the first outer peripheral heat insulating material 10 is used. As a material satisfying these conditions, the graphite sheet and refractory metal carbide described in the first embodiment can be used. Thus, although the low resistance member 20 can be comprised with a graphite sheet or a high melting point metal carbide, when comprising with a high melting point metal carbide, it is preferable to form the low resistance member 20 as follows.

  Specifically, first, a cylindrical refractory metal is accommodated in the SiC single crystal manufacturing apparatus 1 in a state of being arranged on the inner peripheral surface of the first outer peripheral heat insulating material 10. In this state, carbonizing gas is introduced into the vacuum vessel 6 while performing induction heating by the first and second heating devices 13 and 14. Thereby, a refractory metal carbide is formed by carbonizing the inner peripheral surface side of the cylindrical refractory metal. Thus, the low resistance member 20 can be configured such that the inner peripheral surface side is made of a refractory metal carbide and the outer peripheral surface side is made of a refractory metal. When all of the low resistance member 20 is made of a refractory metal carbide, it tends to be relatively brittle. However, the structure of this embodiment allows the low resistance member 20 to have a physically strong structure. It becomes.

  As described above, the low resistance member 20 may be arranged so as to cover the entire inner peripheral surface of the cylindrical first outer peripheral heat insulating material 10. If it does in this way, it will become possible to suppress precipitation of solid SiC by SiC material gas osmose | permeating the inner peripheral surface of the 1st outer periphery heat insulating material 10, obtaining the effect of 1st Embodiment.

  In addition, when comprising the 1st outer periphery heat insulating material 10 by the some division | segmentation part 10a-10c, it is also considered that the low resistance member 20 is comprised by TaC coating the outer wall surface of the some division | segmentation part 10a-10c. However, with such a structure, since a gap exists between the TaC coatings, a local discharge phenomenon may occur in the gap between the divided portions 10a to 10c. For this reason, as in the present embodiment, the low resistance member 20 is formed in a cylindrical shape, and the low resistance member 20 is fixed to each of the divided portions 10a to 10c directly or via an adhesive or the like. It is necessary.

(Third embodiment)
A third embodiment of the present invention will be described. In the present embodiment, the configuration of the low-resistance member 20 is changed with respect to the second embodiment, and the other aspects are the same as those of the second embodiment. Therefore, only the portions different from the first embodiment will be described.

  FIG. 4 is a cross-sectional view of the SiC single crystal manufacturing apparatus 1 according to the present embodiment. FIG. 5 is a view showing the first outer peripheral heat insulating material 10 and the low resistance member 20 provided in the SiC single crystal manufacturing apparatus 1 according to the present embodiment. FIG. 5 (a) is a top view, and FIG. b) is a perspective view.

  As shown in FIG. 4 and FIG. 5, also in this embodiment, the low resistance member 20 disposed on the inner peripheral surface side of the first outer peripheral heat insulating material 10 has a cylindrical shape along the inner peripheral surface. A part of the inner peripheral surface of the material 10 is covered with the low resistance member 20 instead of the entire inner peripheral surface, specifically, the intermediate position in the axial direction of the first outer peripheral heat insulating material 10. In the SiC single crystal manufacturing apparatus 1 of the present embodiment, as shown in FIG. 4, the raw material gas is guided radially outward at the tip portion on the pedestal 9 side of the heating container 8, which is supplied to the first outer peripheral heat insulating material 10. It will collide. At this time, the low-resistance member 20 is arranged in a place where the source gas first collides with the first outer peripheral heat insulating material 10, that is, a place where the gas partial pressure of the source gas becomes high.

  Thus, the low resistance member 20 can also be disposed on a part of the inner peripheral surface of the cylindrical first outer peripheral heat insulating material 10. In the present embodiment, the low resistance member 20 is arranged at a location where the source gas first collides with the first outer peripheral heat insulating material 10, that is, a location where the gas partial pressure of the source gas becomes high. With such a configuration, the place where the solid SiC is most likely to precipitate can be covered with the low-resistance member 20, so that the precipitation of solid SiC can be suppressed.

(Fourth embodiment)
A fourth embodiment of the present invention will be described. In the present embodiment, the configuration of the low-resistance member 20 is changed with respect to the second embodiment, and the other aspects are the same as those of the second embodiment. Therefore, only the portions different from the first embodiment will be described.

  FIG. 6 is a view showing the first outer peripheral heat insulating material 10 and the low-resistance member 20 provided in the SiC single crystal manufacturing apparatus 1 according to the present embodiment. FIG. 6 (a) is a top view, and FIG. 6 (b). Is a perspective view.

  As shown in FIG. 6, in the present embodiment, not only the inner peripheral surface side of the first outer peripheral heat insulating material 10 but also the outer peripheral surface side is arranged with a low resistance member 20 having a cylindrical shape along the outer peripheral surface, The first peripheral heat insulating material 10 is fixed to each of the plurality of divided portions 10a to 10c directly or via an adhesive or the like. As described above, the low resistance member 20 may be arranged on the outer peripheral surface side in addition to the inner peripheral surface side of the first outer peripheral heat insulating material 10.

  If the low resistance member 20 is made of a material having low gas permeability while having such a structure, the raw material gas is not only supplied to the outer peripheral surface side but also to the outer peripheral surface side of the first outer peripheral heat insulating material 10. Penetration can be prevented, and precipitation of solid SiC in the first outer peripheral heat insulating material 10 can be further suppressed.

(Other embodiments)
In the first embodiment, the low resistance member 20 provided in the first outer peripheral heat insulating material 10 covers the whole area of the joints of the divided portions 10a to 10c. However, at least one of the joint parts is not covered. The low resistance member 20 should just be provided so that a part may be covered. In the first embodiment, the low resistance member 20 is arranged on the inner peripheral surface side of the first outer peripheral heat insulating material 10, but may be arranged on the outer peripheral surface side.

  In the third embodiment, the low resistance member 20 is disposed so as to cover a part of the inner peripheral surface of the first outer peripheral heat insulating material 10. Specifically, an intermediate position in the axial direction of the first outer peripheral heat insulating material 10 is covered with the low resistance member 20. However, the portion covered with the low resistance member 20 is determined by the form of the SiC single crystal manufacturing apparatus 1 and does not necessarily have to be an intermediate position in the axial direction of the first outer peripheral heat insulating material 10. That is, the low resistance member 20 may be disposed in a location where the source gas first collides in the first outer peripheral heat insulating material 10, that is, a location where the gas partial pressure of the source gas becomes high.

  In addition, although the place where source gas collides first among the 1st outer periphery heat insulating materials 10 changes with forms of the SiC single crystal manufacturing apparatus 1, solid SiC tends to precipitate according to the form of the SiC single crystal manufacturing apparatus 1. A low-resistance member 20 may be disposed so as to select a place and cover the place.

  Moreover, in each said embodiment, although it was set as the structure which cut | disconnected in the direction parallel to the center axis | shaft about the 1st outer periphery heat insulating material 10, and was set as the some division | segmentation part 10a-10c, not only the 1st outer periphery heat insulating material 10 but the 1st The same structure as that of the first outer peripheral heat insulating material 10 can be used for the two outer peripheral heat insulating materials 12. Moreover, although the case where the 1st, 2nd outer periphery heat insulating materials 10 and 12 were provided as an outer periphery heat insulating material surrounding the circumference | surroundings of the heating container 8, only one may be sufficient.

DESCRIPTION OF SYMBOLS 1 SiC single crystal manufacturing apparatus 3 Raw material gas 5 Seed crystal 6 Vacuum container 8 Heating container 8a Gas inlet 9 Base 10 1st outer periphery heat insulating material 12 2nd outer periphery heat insulating material 13 1st heating device 14 2nd heating device 20 Low resistance member

Claims (6)

By disposing a seed crystal (5) composed of a silicon carbide single crystal substrate on the pedestal (9) and supplying a silicon carbide source gas (3) from below the seed crystal (5), In the silicon carbide single crystal manufacturing apparatus for growing a silicon carbide single crystal on the surface of the seed crystal (5),
A heating container (8) disposed on the upstream side of the flow path of the source gas (3) relative to the pedestal (9) and heating the source gas (3);
A heating device (13, 14) for induction heating the heating vessel (8);
A cylindrical outer peripheral heat insulating material (10) composed of graphite arranged around the outer periphery of the heating vessel (8),
The outer peripheral heat insulating material (10) has a plurality of divided portions (10a to 10c) divided by a dividing surface that is divided in a direction along the central axis of the outer peripheral heat insulating material (10). (10a to 10c) are combined to form a cylindrical shape,
Furthermore, it is comprised with a low resistance material rather than the graphite which comprises the said outer periphery heat insulating material (10), and it fixes to the location of the joint of the said some division | segmentation part (10a-10c), and adjacent division | segmentation part (10a- 10c) An apparatus for producing a silicon carbide single crystal, comprising a low resistance member (20) for connecting each other.   The low resistance member (20) has a cylindrical shape along the inner peripheral surface or outer peripheral surface of the outer peripheral heat insulating material (10), and covers at least a part of the inner peripheral surface or outer peripheral surface of the outer peripheral heat insulating material (10). The apparatus for producing a silicon carbide single crystal according to claim 1.   The low resistance member (20) has an inner peripheral surface of the outer peripheral heat insulating material (10) or a cylindrical shape along the outer peripheral surface, and covers at least one whole region of the inner peripheral surface and the outer peripheral surface of the outer peripheral heat insulating material (10). The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein the silicon carbide single crystal manufacturing apparatus is covered.   The low resistance member (20) covers a position where the source gas (3) flowing between the pedestal (9) and the heating vessel (8) first collides among the outer peripheral heat insulating material (10). The apparatus for producing a silicon carbide single crystal according to claim 2, wherein:   The said low resistance member (20) is comprised with the graphite sheet or the high melting point metal carbide, The manufacturing apparatus of the silicon carbide single crystal as described in any one of Claim 1 thru | or 3 characterized by the above-mentioned. The seed crystal (5) composed of a silicon carbide single crystal substrate is arranged on the pedestal (9), and the seed crystal (5) located above by supplying the silicon carbide source gas (3) from below. In the method for producing a silicon carbide single crystal, the silicon carbide single crystal is grown on the surface of the seed crystal (5).
Using the hollow part of the heating container (8) constituted by a hollow cylindrical member as a gas supply path, the cylindrical outer peripheral heat insulating material (10) is disposed so as to surround the outer periphery of the heating container (8),
The outer peripheral heat insulating material (10) is constituted by a plurality of divided portions (10a to 10c) divided by a dividing surface that is divided in a direction along the central axis of the outer peripheral heat insulating material (10). A cylindrical shape is configured by combining the divided portions (10a to 10c), and the joints of the plurality of divided portions (10a to 10c) constituting the outer peripheral heat insulating material (10) By fixing the adjacent divided parts (10a to 10c) by fixing the low resistance member (20) made of a material having a lower resistance than the graphite constituting the outer peripheral heat insulating material (10),
In this state, the source gas (3) is introduced from one end of the heating vessel (8) while induction heating the heating vessel (8) with a heating device (13, 14), and the heating vessel (8 ) Is led out from the other end of the source gas (3) to supply the seed crystal (5) to grow the silicon carbide single crystal.

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