JP2019131422A - crucible - Google Patents

Abstract

To provide a crucible capable of producing a high quality crystal by reducing thermal stress imposed on a crystal.SOLUTION: A crucible 11 is used to grow a silicon carbide single crystal by a sublimation method. The crucible 11 includes a cylindrical peripheral wall part 12, a bottom wall part 13 that is connected to the peripheral wall part 12 and closes an opening of the peripheral wall part 12, a pedestal part 23 as a holding part for holding a seed crystal T in the space 15 enclosed by the peripheral wall part 12, and a heat radiation suppressing member 31 that is arranged at a distance from the seed crystal T at a side opposite to the side where the bottom wall part 13 is positioned in the growth direction of the single crystal and suppresses heat radiation from the seed crystal T side held by the pedestal part 23 as the holding part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a crucible.

  A silicon carbide single crystal can be produced by a method (sublimation method) in which a raw material powder is sublimated in a crucible and recrystallized on a seed crystal. For example, Patent Document 1 discloses a technique for manufacturing a silicon carbide single crystal by a sublimation method.

JP 2011-207691 A

  In the production of a silicon carbide single crystal by the sublimation method, it is required to reduce the thermal stress applied to the crystal by reducing the temperature difference in the crystal plane.

  Accordingly, an object of the present invention is to provide a crucible that can produce a high-quality crystal by reducing the thermal stress applied to the crystal.

  The crucible according to the present invention is used for growing a silicon carbide single crystal by a sublimation method. The crucible includes a cylindrical peripheral wall portion, a bottom wall portion that is connected to the peripheral wall portion and closes one opening of the peripheral wall portion, a holding portion that holds a seed crystal in a space surrounded by the peripheral wall portion, and a single crystal A heat dissipation suppressing member that is disposed on the opposite side to the side where the bottom wall portion is located in the growth direction and is spaced from the seed crystal, and that suppresses heat dissipation from the seed crystal side held by the holding portion.

  According to the crucible, a high-quality crystal can be produced by reducing the thermal stress applied to the crystal.

It is a schematic sectional drawing which shows the structure of the crucible which concerns on one Embodiment of this application. It is a simulation figure which shows the temperature distribution of a part of space at the time of using the crucible of the structure similar to the crucible which concerns on one Embodiment of this application. It is a simulation figure which shows the temperature distribution of a part of space at the time of using the crucible which is not provided with the heat dissipation suppression member. It is a schematic sectional drawing which shows the structure of the crucible which is not provided with the heat dissipation suppression member. It is a schematic sectional drawing which shows the structure of the crucible which concerns on other embodiment of this application. It is a simulation figure which shows the temperature distribution of a part of space at the time of using the crucible of the structure similar to the crucible which concerns on other embodiment of this application. It is a schematic sectional drawing which shows the structure of the crucible which concerns on other embodiment of this application. It is a simulation figure which shows the temperature distribution of a part of space at the time of using the crucible of the structure similar to the crucible which concerns on other embodiment of this application. It is a schematic sectional drawing which shows the structure of the crucible which concerns on other embodiment of this application. It is a schematic sectional drawing which shows the structure of the crucible which concerns on other embodiment of this application. It is a schematic sectional drawing which shows the structure of the crucible which concerns on other embodiment of this application.

[Description of Embodiment of Present Invention]
First, embodiments of the present invention will be listed and described. The crucible of the present application is used for growing a silicon carbide single crystal by a sublimation method. The crucible includes a cylindrical peripheral wall portion, a bottom wall portion that is connected to the peripheral wall portion and closes one opening of the peripheral wall portion, a holding portion that holds a seed crystal in a space surrounded by the peripheral wall portion, and a single crystal A heat dissipation suppressing member that is disposed on the opposite side to the side where the bottom wall portion is located in the growth direction and is spaced from the seed crystal, and that suppresses heat dissipation from the seed crystal side held by the holding portion.

  The seed crystal held in the space surrounded by the peripheral wall portion is heated from the peripheral wall portion side. The single crystal grows from the surface side where the seed crystal raw material powder is disposed in the growth space of the single crystal. In order to promote the growth of a high-quality single crystal, it is desirable that the temperature uniformity of the growth space of the single crystal is high in the direction (radial direction) along the cross section perpendicular to the growth direction of the single crystal. Here, when the single crystal is grown, the seed crystal has a large amount of heat radiation toward the opposite side to the growth space. In this case, the temperature becomes lower as the position becomes closer to the center in the radial direction far from the peripheral wall. Then, the growth of the single crystal becomes a so-called convex growth, and strain is generated during the growth of the single crystal, and cracks and dislocations due to the strain are generated. However, the crucible of the present application is arranged with a distance from the seed crystal on the side opposite to the side where the bottom wall portion is located in the growth direction of the single crystal, and the heat dissipation suppresses heat dissipation from the seed crystal side held by the holding portion. It is the structure provided with the suppression member. If it does so, the thermal radiation in the opposite side to the side in which a bottom wall part is located will be suppressed by the thermal radiation suppression member, and the temperature difference of the radial direction in the growth space of a single crystal can be made small. Therefore, it is possible to manufacture a high-quality single crystal by increasing the temperature uniformity in the radial direction of the growth space of the single crystal and reducing the thermal stress applied to the crystal during the growth of the single crystal.

  The crucible further includes a lid portion connected to the peripheral wall portion and closing the other opening of the peripheral wall portion, and the lid portion includes a seed crystal held in the holding portion when seen in a plan view from the growth direction of the single crystal. The space | gap is provided in the overlapping position and the heat dissipation suppression member may be arrange | positioned in the space | gap. By comprising in this way, a heat dissipation suppression member can be arrange | positioned in the appropriate location at the time of obtaining the effect of heat dissipation suppression, and a high quality single crystal can be manufactured more efficiently.

  In the crucible, the holding portion has a pedestal first surface to which the seed crystal is attached and a pedestal second surface located on the opposite side of the pedestal first surface in the growth direction of the single crystal, and the pedestal first surface is a bottom wall. A heat dissipation suppressing member may be disposed including a pedestal portion disposed at a position facing the portion, and spaced from the pedestal portion in the growth direction of the single crystal. By comprising in this way, the thermal radiation of the base part to which a seed crystal is attached can also be suppressed efficiently. Therefore, it is possible to maintain a higher temperature uniformity in the radial direction in the growth space of the single crystal.

  In the above crucible, the holding part includes an extension part extending in a cylindrical shape into a space surrounded by the peripheral wall part toward the bottom wall part, and includes an extension part having a wall surface on the inward side. You may make it hold | maintain. By comprising in this way, when suppressing the thermal radiation from the seed crystal side hold | maintained by the extension part, a thermal radiation suppression member can be arrange | positioned in a more suitable position. Therefore, it is possible to maintain a higher temperature uniformity in the radial direction in the growth space of the single crystal.

  In the crucible, the heat dissipation suppressing member includes a first region located in the center when viewed in plan from the growth direction of the single crystal, and a second region located on the outer side of the first region. The distance between the first region and the seed crystal in the growth direction may be shorter than the distance between the second region and the seed crystal. As for the seed crystal, the center is more likely to dissipate heat when seen in a plan view from the growth direction of the single crystal. Therefore, by adopting such a configuration, the heat dissipation in the first region can be further suppressed than the heat dissipation in the second region, and the radial heat uniformity in the growth space of the single crystal can be maintained higher.

  In the above crucible, the heat dissipation suppressing member includes a first heat dissipation adjustment region in which the distance from the seed crystal in the growth direction of the single crystal becomes longer as the distance from the seed crystal in the growth direction of the single crystal becomes closer to the outer side when viewed in plan. May be. With such a configuration, the temperature difference in the radial direction in the growth space of the single crystal can be appropriately reduced, and the thermal uniformity in the radial direction in the growth space of the single crystal can be maintained at a higher level.

  The crucible of the present application is used for growing a silicon carbide single crystal by a sublimation method. The crucible has a cylindrical peripheral wall portion, a bottom wall portion that is connected to the peripheral wall portion and closes one opening of the peripheral wall portion, a rod-shaped portion that extends into the space surrounded by the peripheral wall portion toward the bottom wall portion, A holding portion that is connected to an end portion of the bottom wall portion side and holds the seed crystal in a space surrounded by the peripheral wall portion, and a seed crystal on a side opposite to the side where the bottom wall portion is located in the growth direction of the single crystal. A heat dissipation suppressing member that is disposed at an interval and suppresses heat dissipation from the seed crystal side held by the holding portion. Even with such a configuration, it is possible to increase the temperature uniformity in the radial direction of the growth space of the single crystal, and to reduce the thermal stress applied to the crystal during the growth of the single crystal, thereby producing a high-quality single crystal. .

  In the crucible, the heat radiation suppressing member may be connected to the rod-shaped portion, and may include a second heat radiation adjusting region in which the distance from the holding portion in the growth direction of the single crystal becomes longer as the rod-shaped portion is approached. In a crucible provided with a rod-shaped part, it is difficult to radiate heat at a position close to the rod-shaped part. Therefore, by adopting such a configuration, it is possible to further suppress heat dissipation at a position far from the rod-shaped portion, and to maintain higher thermal uniformity in the radial direction in the growth space of the single crystal.

  In the above crucible, the heat dissipation suppressing member may be configured to include a region extending obliquely with respect to the growth direction of the single crystal. By configuring in this way, the temperature in the radial direction in the growth space of the single crystal can be appropriately adjusted, and the thermal uniformity in the radial direction in the growth space of the single crystal can be maintained higher.

  In the crucible, a plurality of heat dissipation suppressing members may be provided at intervals in the growth direction of the single crystal. By comprising in this way, the thermal uniformity of the radial direction in the growth space of a single crystal can be efficiently improved by the some heat dissipation suppression member.

  In the crucible, the heat dissipation suppressing member may be made of graphite. Graphite can more reliably suppress heat dissipation from the seed crystal side even at high temperatures, and can improve the thermal uniformity in the radial direction in the growth space of the single crystal.

[Details of the embodiment of the present invention]
Next, a crucible according to an embodiment of the present application will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a schematic cross-sectional view showing the structure of a crucible according to an embodiment of the present application. Referring to FIG. 1, a crucible 11 according to an embodiment of the present application is used for growing a silicon carbide single crystal by a sublimation method.

  The crucible 11 includes a cylindrical peripheral wall portion 12, a bottom wall portion 13, and a lid portion 14. The peripheral wall part 12, the bottom wall part 13, and the cover part 14 are made of carbon (graphite), for example. Note that, on the outer diameter side of the peripheral wall portion 12 of the crucible 11, for example, a heating unit that heats the crucible 11 when a single crystal is grown is disposed. For example, an induction heating coil is used as the heating unit.

  The peripheral wall portion 12 has a cylindrical shape. A central axis α of the peripheral wall portion 12 indicated by a one-dot chain line extends along the growth direction of the single crystal.

  The bottom wall portion 13 is connected to the peripheral wall portion 12 and closes one opening of the peripheral wall portion 12. The bottom wall portion 13 has a disk shape. The peripheral wall portion 12 and the bottom wall portion 13 are integrally formed. In a space 15 surrounded by the peripheral wall portion 12 and the bottom wall portion 13, silicon carbide raw material powder M is disposed. The bottom wall portion 13 has a bottom wall surface 16 located on the space 15 side. The raw material powder M is disposed on the bottom wall surface 16. The single crystal grows in the direction indicated by the arrow D in FIG. 1 from the surface of the seed crystal T facing the bottom wall surface 16.

  The lid portion 14 is connected to the peripheral wall portion 12 and closes the other opening of the peripheral wall portion 12. The lid portion 14 is configured to be detachable from the peripheral wall portion 12. The lid portion 14 has a disk shape. The lid 14 is removed, a seed crystal T is attached to a pedestal 23 which will be described later, and the lid 14 is attached to the peripheral wall 12 to place the seed crystal T in the crucible 11.

  A gap 29 is provided in the lid portion 14. Using the gap 29, for example, the temperature inside the crucible 11 is detected by a radiation thermometer arranged outside the crucible 11. The gap 29 is configured such that the diameter of the opening 21 opened to the outside is small, and the diameter of the region disposed from the opening 21 toward the bottom wall 13 is increased. The air gap 29 is surrounded by the wall surface 22 located in the radial direction.

  The crucible 11 includes a holding part that holds the seed crystal T in a space 15 surrounded by the peripheral wall part 12. The holding part includes a pedestal part 23. The pedestal portion 23 has a pedestal first surface 26 to which the seed crystal T is attached, and a pedestal second surface 27 located on the opposite side of the pedestal first surface 26 in the growth direction of the single crystal. The pedestal portion 23 is disposed at a position where the pedestal first surface 26 faces the bottom wall surface 16. The pedestal portion 23 is provided so as to be attached to the wall surface 24 of the lid portion 14 facing the bottom wall surface 16. In FIG. 1, the boundary between the base portion 23 and the lid portion 14 is indicated by a broken line. The seed crystal T is held on the pedestal portion 23 such that the seed crystal first surface 28 located on the pedestal portion 23 side in the growth direction of the single crystal is attached to the pedestal first surface 26. The pedestal portion 23 holds the seed crystal T at a position overlapping the position where the void 29 is provided when viewed in plan from the growth direction of the single crystal. In the present embodiment, the pedestal portion 23 is a holding portion that holds the seed crystal T.

  The crucible 11 includes a heat dissipation suppressing member 31. The heat dissipation suppressing member 31 is plate-shaped. The heat dissipation suppressing member 31 is disposed in the gap 29. The heat dissipation suppressing member 31 is provided continuously from the wall surface 22. The heat dissipation suppressing member 31 is arranged at a distance from the seed crystal T on the side opposite to the side where the bottom wall portion 13 is located in the growth direction of the single crystal. In this case, the heat dissipation suppressing member 31 is disposed at a distance from the pedestal 23 in the growth direction of the single crystal. The heat dissipation suppressing member 31 suppresses heat dissipation from the seed crystal T side held by the pedestal portion 23. In this case, the heat dissipation suppressing member 31 also suppresses heat dissipation of the pedestal portion 23.

The heat dissipation suppressing member 31 includes a first region 32 located on the center side including the central axis α and a second region 33 located on the outer side from the first region 32 when viewed in plan from the growth direction of the single crystal. Have The first region 32 is provided so as to extend along a cross section perpendicular to the central axis α. The width of the first region 32 is indicated by the width W ₁ in FIG. In this case, the width W ₁ of the first region 32, means the diameter. The distance L ₁ between the first region 32 and the seed crystal T, specifically the seed crystal first surface 28 in the growth direction of the single crystal is the second region 33 and the seed crystal T in the growth direction of the single crystal. Is configured to be shorter than the distance L ₂ from the seed crystal first surface 28. The second region 33 is provided so as to extend inclined with respect to the central axis α. In this case, the second region 33 is located closer to the wall surface 22 than the first region 32 when viewed in plan from the growth direction of the single crystal. The distance between the second region 33 and the seed crystal T in the growth direction of the single crystal increases as it approaches the outer side. That is, the heat dissipation suppressing member 31 includes the second region 33 as the first heat dissipation adjustment region in which the distance from the seed crystal T in the growth direction of the single crystal increases as it approaches the outer side.

  The seed crystal T held in the space 15 surrounded by the peripheral wall portion 12 is heated from the peripheral wall portion 12 side. A single crystal grows from the surface side where the raw material powder M of the seed crystal T is arranged in the single crystal growth space 15. In order to promote the growth of a high-quality single crystal, it is desirable that the temperature uniformity of the growth space 15 of the single crystal is high in a direction (radial direction) along a cross section perpendicular to the growth direction of the single crystal. Here, during the growth of the single crystal, the seed crystal T has a large amount of heat radiation toward the opposite side of the growth space 15. Specifically, the heat radiation amount in the direction opposite to the direction indicated by the arrow D in FIG. 1 is large. In this case, the temperature becomes lower as the position becomes closer to the radial center position away from the peripheral wall portion 12, that is, the central axis α. Then, the growth of the single crystal becomes a so-called convex growth, and strain is generated during the growth of the single crystal, and cracks and dislocations due to the strain are generated. However, the crucible 11 described above is arranged at a distance from the seed crystal T on the side opposite to the side on which the bottom wall portion 13 is located in the growth direction of the single crystal, and from the seed crystal T side held by the pedestal portion 23. It is the structure provided with the heat dissipation suppression member 31 which suppresses heat dissipation. If it does so, the thermal radiation in the opposite side to the side in which the bottom wall part 13 is located will be suppressed by the thermal radiation suppression member 31, and the temperature difference of the radial direction in the growth space 15 of a single crystal can be made small. Therefore, it is possible to manufacture a high-quality single crystal by increasing the thermal uniformity in the radial direction of the growth space 15 of the single crystal and reducing the thermal stress applied to the crystal during the growth of the single crystal.

  In this embodiment, the holding portion has a pedestal first surface 26 to which a seed crystal is attached and a pedestal second surface 27 located on the opposite side of the pedestal first surface 26 in the growth direction of the single crystal. A heat dissipation suppressing member 31 is disposed including a pedestal portion 23 disposed at a position where one surface 26 faces the bottom wall portion 13 and spaced from the pedestal portion 23 in the growth direction of the single crystal. If it does so, the thermal radiation of the base part 23 to which the seed crystal T is attached can be suppressed efficiently. Therefore, it is possible to maintain a higher temperature uniformity in the radial direction in the growth space 15 of the single crystal.

  In this embodiment, the lid portion 14 is provided with a gap 29 at a position overlapping the seed crystal T held by the pedestal portion 23 as viewed in plan from the growth direction of the single crystal. A suppression member 31 is disposed. By comprising in this way, the heat dissipation suppression member 31 can be arrange | positioned in the appropriate location at the time of obtaining the effect of heat dissipation suppression, and a high quality single crystal can be manufactured more efficiently.

  In this embodiment, the heat dissipation suppressing member 31 includes a first region 32 that is located in the center when viewed in plan from the growth direction of the single crystal, and a second region 33 that is located on the outer side of the first region 32. The distance between the first region 32 and the seed crystal T in the growth direction of the single crystal is configured to be shorter than the distance between the second region 33 and the seed crystal T. As for the seed crystal T, the center of the seed crystal T is more likely to dissipate heat as viewed in plan from the growth direction of the single crystal. Therefore, the heat dissipation in the first region 32 can be further suppressed than the heat dissipation in the second region 33, and the radial heat uniformity in the single crystal growth space 15 can be maintained higher.

  In this embodiment, the heat radiation suppression member 31 is a first heat radiation adjustment region in which the distance from the seed crystal T in the growth direction of the single crystal becomes longer as it approaches the outer side as viewed in plan from the growth direction of the single crystal. The second area 33 is included. Therefore, the temperature difference in the radial direction in the single crystal growth space 15 can be appropriately reduced, and the thermal uniformity in the radial direction in the single crystal growth space 15 can be maintained higher.

  In this embodiment, the heat dissipation suppressing member 31 includes a second region 33 extending obliquely with respect to the growth direction of the single crystal. Therefore, the radial temperature in the single crystal growth space 15 can be adjusted appropriately, and the radial heat uniformity in the single crystal growth space 15 can be maintained higher.

  Here, the difference between the thermal uniformity of the crucible 11 according to the embodiment of the present application including the heat dissipation suppressing member 31 and the thermal uniformity of the crucible 101 not including the heat dissipation suppressing member 31 will be described. FIG. 2 is a simulation diagram showing a temperature distribution of a part of the space 15 when a crucible having the same configuration as the crucible 11 according to the embodiment of the present application is used. FIG. 3 is a simulation diagram showing a temperature distribution of a part of the space 15 when the crucible 101 without the heat radiation suppressing member 31 is used. In addition, the structure of the crucible similar to the crucible 101 without the heat radiation suppressing member 31 is shown in FIG. The crucible 11 and the crucible 101 differ in whether or not the heat dissipation suppressing member 31 is provided, and the other configurations are the same. 2 and 3 show a region from the central axis α toward the outer diameter side in a region immediately below the seed crystal T where a difference in temperature distribution is likely to occur.

  First, referring to FIG. 3 and FIG. 4, in the case of the crucible 101 that does not include the heat dissipation suppressing member 31, the region 37 a, the region 37 b, the region 37 c, the region 37 d, and the region in the direction indicated by the arrow D along the central axis α The temperature range of eight regions 37a to 37h such as 37e, region 37f, region 37g, and region 37h is straddled. In the portion where the outer edge portion 30 of the seed crystal T is located, the region 37f, the region 37g, the region 37h, the region 37i, the region 37j, the region 37k, the region 37l, the region 37m, the region 37n in the direction indicated by the arrow D, and The temperature range of ten regions 37f to 37o such as the region 37o is straddled. That is, in the case of the crucible 101 that does not include the heat dissipation suppressing member 31, the temperature distribution has a large convex shape with the central axis α as the tip in the direction indicated by the arrow D, and the temperature uniformity in the radial direction in the single crystal growth space 15. Is low.

  On the other hand, referring to FIG. 2, in the case of the crucible 11 including the heat dissipation suppressing member 31, the region 36 a, the region 36 b, the region 36 c, the region 36 d, the region 36 e, and the direction in the direction indicated by the arrow D along the central axis α The temperature ranges of the six regions 36a to 36f such as the region 36f are straddled. Further, in the portion where the outer edge 30 of the seed crystal T is located, eight regions such as a region 36a, a region 36b, a region 36c, a region 36d, a region 36e, a region 36f, a region 36g, and a region 36h are arranged in the direction indicated by the arrow D. It extends over the temperature range of 36a to 36h. That is, in the case of the crucible 11 provided with the heat dissipation suppressing member 31, the temperature is almost the same in the central axis α side and the outer edge portion 30, and the thermal uniformity in the radial direction in the single crystal growth space 15 is high. In the case where a crucible having the same structure as the crucible 11 shown in FIG. 1 is used, a portion where the central axis α is located at a position where a 50 mm single crystal is grown from the surface facing the bottom wall portion 13 of the seed crystal T. The temperature difference from the portion where the outer edge portion 30 is located is within 3 ° C.

(Embodiment 2)
Next, a second embodiment which is another embodiment of the present application will be described. The crucible 11 in the second embodiment has basically the same structure as that in the first embodiment, and has the same effect. However, the crucible 11 in the second embodiment is different from that in the first embodiment in the structure of the heat dissipation suppressing member 31.

FIG. 5 is a schematic cross-sectional view showing the structure of a crucible 11 according to another embodiment of the present application. Referring to FIG. 5, the width W ₂ of the first region 32 of the heat radiation suppressing member 31 is narrower compared to the width W ₁ of the first region 32 shown in FIG. In this case, the distance L _1, are the same distance as the case shown in FIG. Further, the inclination angle of the second region 33 with respect to the central axis α is also different from that of the second region 33 shown in FIG.

  FIG. 6 is a simulation diagram showing a temperature distribution of a part of the space 15 when a crucible having the same configuration as the crucible 11 shown in FIG. 5 is used. FIG. 6 shows the temperature distribution in the same region as FIG. Referring to FIG. 6, the temperature range of six regions 39a to 39f such as region 39a, region 39b, region 39c, region 39d, region 39e, and region 39f is straddled in the direction indicated by arrow D along central axis α. Yes. In the portion where the outer edge portion 30 of the seed crystal T is located, seven regions 39a to 39g such as a region 39a, a region 39b, a region 39c, a region 39d, a region 39e, a region 39f, and a region 39g are arranged in the direction indicated by the arrow D. Across the temperature range. In this case, although there is a slight temperature difference between the radial center, that is, the radial central position between the central axis α and the outer edge 30, the position of the central axis α, and the position where the outer edge 30 is provided. 2 has the same tendency as in the case shown in FIG. 2, and the thermal uniformity in the radial direction in the growth space 15 of the single crystal is high.

(Embodiment 3)
Next, Embodiment 3 which is still another embodiment of the present application will be described. The crucible 11 in the third embodiment has basically the same structure as that in the first embodiment and has the same effects. However, the crucible 11 in the second embodiment is different from that in the first embodiment in the structure of the heat dissipation suppressing member 31.

FIG. 7 is a schematic cross-sectional view showing the structure of a crucible 11 according to still another embodiment of the present application. With reference to FIG. 7, the heat dissipation suppressing member 31 has a flat plate shape. That is, compared with the case of the crucible 11 shown in FIGS. 1 and 5, the crucible 11 shown in FIG. 7 is configured not to include the second region 33. In this case, the distance _{L 3,} is longer than the distance _{L 1.}

  FIG. 8 is a simulation diagram showing a temperature distribution of a part of the space 15 when a crucible having the same configuration as the crucible 11 shown in FIG. 7 is used. FIG. 8 shows the temperature distribution in the same region as FIG. Referring to FIG. 8, the temperature ranges of six regions 38 a to 38 f such as region 38 a, region 38 b, region 38 c, region 38 d, region 38 e, and region 38 f are straddled in the direction indicated by arrow D along central axis α. Yes. In the portion where the outer edge portion 30 of the seed crystal T is located, eight regions such as a region 38c, a region 38d, a region 38e, a region 38f, a region 38g, a region 38h, a region 38i, and a region 38j are arranged in the direction indicated by the arrow D. It extends over the temperature range of 38c to 38j. That is, in this case as well, the same tendency as in the case shown in FIG. 2 is obtained. Although there is a slight temperature difference, the region is almost the same temperature on the central axis α side and the outer edge 30 side. The soaking in the radial direction is high.

(Embodiment 4)
Next, a fourth embodiment which is still another embodiment will be described. The crucible 11 in the fourth embodiment has basically the same structure as that in the first embodiment and has the same effect. However, the crucible 11 in the fourth embodiment is different from that in the first embodiment in the structure of the heat dissipation suppressing member 31.

  FIG. 9 is a schematic cross-sectional view showing the structure of a crucible 11 according to still another embodiment of the present application. Referring to FIG. 9, a plurality of heat dissipation suppressing members 31 are provided. Specifically, the heat dissipation suppressing member 31 includes a first heat dissipation suppressing member 41 provided at a position closest to the pedestal portion 23, and the pedestal portion 23 spaced apart from the first heat dissipation suppressing member 41 in the growth direction of the single crystal. A second heat radiation suppressing member 42 provided on the side opposite to the side where the base part 23 is located, and a third heat radiation provided on the side opposite to the side where the pedestal portion 23 is located with a space from the second heat radiation suppressing member 42 in the growth direction of the single crystal. This is a configuration including the suppression member 43.

  By comprising in this way, the heat radiation from the base part 23 side is effectively suppressed by three of the 1st heat radiation suppression member 41, the 2nd heat radiation suppression member 42, and the 3rd heat radiation suppression member 43, and a single crystal The soaking property in the radial direction in the growth space 15 can be further enhanced. In the present embodiment, three heat radiation suppressing members are provided. However, the present invention is not limited to this, and two or four or more heat radiation suppressing members may be provided.

(Embodiment 5)
Next, a fifth embodiment which is still another embodiment will be described. The crucible 11 in the fifth embodiment has basically the same structure as that in the first embodiment and has the same effects. However, the crucible 11 in the fifth embodiment is different from that in the first embodiment in the structure of the holding portion.

  FIG. 10 is a schematic cross-sectional view showing the structure of a crucible 11 according to still another embodiment of the present application. Referring to FIG. 10, the holding portion includes an extending portion 25 extending in a cylindrical shape in a space 15 surrounded by the peripheral wall portion 12 toward the bottom wall portion 13. The extending portion 25 is provided so as to extend from the wall surface 24 in a cylindrical shape. In addition, in FIG. 10, the boundary of the extension part 25 and the cover part 14 is shown with the broken line. The extension part 25 has a wall surface 47 on the inner side. The extending portion 25 holds the seed crystal T with the wall surface 47. Specifically, the seed crystal T is held by the extension portion 25 so that the outer edge portion 30 of the seed crystal T is fitted into the wall surface 47 located on the inner diameter side of the end portion 46 on the bottom wall portion 13 side of the extension portion 25. Is done. In the present embodiment, the extending portion 25 is a holding portion that holds the seed crystal T. That is, it differs from the above-described embodiment in that the pedestal portion 23 is not provided and the seed crystal T is held by the extending portion 25. In this case, nothing is interposed between the seed crystal T and the heat dissipation suppressing member 31. In this embodiment, the wall surface 22 constituting the air gap 29 and the inner wall surface 47 of the extending portion 25 are connected in a straight line in the growth direction of the single crystal. The heat dissipation suppressing member 31 suppresses heat dissipation from the seed crystal T side. Even in the crucible 11 having such a configuration, when suppressing heat dissipation from the seed crystal T side, the heat dissipation suppressing member 31 can be disposed at a more appropriate position, and the radial direction in the growth space 15 of the single crystal can be arranged. The soaking property can be maintained higher.

(Embodiment 6)
Next, the sixth embodiment which is still another embodiment will be described. The crucible 11 in the sixth embodiment has basically the same structure as that in the first embodiment and has the same effects. However, the crucible 11 in the sixth embodiment is different from that in the first embodiment in the structure of the lid portion 14 and the like.

  FIG. 11 is a schematic cross-sectional view showing a part of a crucible 11 according to still another embodiment of the present application. Referring to FIG. 11, a crucible 11 is connected to a cylindrical peripheral wall portion 12, a peripheral wall portion 12, a bottom wall portion 13 that closes one opening of the peripheral wall portion 12, and a peripheral wall portion 12. And a lid portion 14 that closes the other opening of the portion 12. There is no gap 29 in the lid portion 14. Further, the crucible 11 does not include the pedestal portion 23. In these points, it differs from the structure of the crucible 11 in Embodiment 1 etc. mentioned above. The crucible 11 is connected to the rod-shaped portion 51 extending into the space 15 surrounded by the peripheral wall portion 12 toward the bottom wall portion 13 and the end of the rod-shaped portion 51 on the bottom wall portion 13 side, and is surrounded by the peripheral wall portion 12. 15 and a holding part 52 that holds the seed crystal T. In this case, the rod-like portion 51 is provided so as to extend from the lid portion 14. The rod-shaped part 51 extends along the central axis α. The holding | maintenance part 52 is disk shape.

  Further, the crucible 11 is arranged at a distance from the seed crystal T on the side opposite to the side where the bottom wall portion 13 is located in the growth direction of the single crystal, and dissipates heat from the seed crystal T side held by the holding portion 52. A heat radiation suppressing member 53 is provided.

The heat dissipation suppressing member 53 is connected to the rod-shaped part 51. The heat dissipation suppression member 53 includes a second heat dissipation adjustment region 54 in which the distance from the holding portion 52 in the growth direction of the single crystal increases as the rod-shaped portion 51 is approached. That is, in the growth direction of the single crystal, the distance L ₄ between the heat dissipation suppressing member 53 and the holding portion 52 in the vicinity of the position where the rod-shaped portion 51 is connected is the heat dissipation suppressing member 53 and the holding portion at a position away from the rod-shaped portion 51. 52 is configured to be longer than the distance L ₅ with respect to 52. In this case, the second heat dissipation adjustment region 54 is the entire heat dissipation suppressing member 53. The heat dissipation suppressing member 53 extends while being inclined with respect to the growth direction of the single crystal.

  Even with such a configuration, it is possible to maintain a higher temperature uniformity in the radial direction in the growth space 15 of the single crystal.

  In this embodiment, the heat radiation suppressing member 53 is connected to the rod-shaped portion 51 and includes a second heat radiation adjustment region in which the distance from the holding portion 52 in the growth direction of the single crystal increases as the rod-shaped portion 51 is approached. . It is difficult to radiate heat at a position close to the rod-shaped portion 51. Therefore, by adopting such a configuration, it is possible to further suppress heat dissipation at a position far from the rod-shaped portion 51 and to maintain higher radial heat uniformity in the single crystal growth space 15.

(Modification)
In the above embodiment, the heat dissipation suppressing members 31 and 53 are made of graphite. However, the present invention is not limited to this, and may be made of other high melting point materials.

  Further, in the above embodiment, the heat dissipation suppressing members 31 and 53 are plate-shaped. However, the present invention is not limited to this, and the heat dissipation suppressing member 31 may have other shapes such as a block shape or a lump shape. Good. Moreover, the heat dissipation suppressing members 31 and 53 may include a surface indicated by a curve in the cross section shown in FIG.

  In the above-described embodiment, the crucible 11 is configured to include the lid portion 14, but is not limited thereto, and may be configured not to include the lid portion 14. In this case, you may comprise so that the other opening of the surrounding wall part 12 may be covered by the base part 23 grade | etc., For example. The holding portion may be configured to extend from the inner diameter surface of the peripheral wall portion 12 to the inner diameter side to hold the seed crystal T.

  It should be understood that the embodiments disclosed herein are illustrative in all respects and are not restrictive in any aspect. The scope of the present invention is defined by the scope of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the scope of the claims.

  The crucible of the present application can be applied particularly advantageously when production of a high-quality silicon carbide single crystal is required.

11 crucible 12 peripheral wall part 13 bottom wall part 14 upper wall part 15 and 29 space 16 bottom wall surface 21 opening part 22 and 24 wall surface 23 pedestal part 25 extension part 26 pedestal first surface 27 pedestal second surface 28 seed crystal first surface 30 Outer edge portion 31, 41, 42, 43, 53 Heat radiation suppressing member 32 First region 33 Second region 36a, 36b, 36c, 36d, 36e, 36f, 36g, 36h, 37a, 37b, 37c, 37d, 37e, 37f 37g, 37h, 37i, 37j, 37k, 37l, 37m, 37n, 37o, 38a, 38b, 38c, 38d, 38e, 38f, 38g, 38h, 38i, 38j, 39a, 39b, 39c, 39d, 39e, 39f , 39 g, 54 Region 46 End 47 Inner diameter surface 51 Bar-shaped portion 52 Holding portion

Claims (11)

A crucible used for growing a silicon carbide single crystal by a sublimation method,
A cylindrical peripheral wall,
A bottom wall connected to the peripheral wall and closing one opening of the peripheral wall;
A holding part for holding a seed crystal in a space surrounded by the peripheral wall part;
A heat dissipation suppressing member that is disposed at a distance from the seed crystal on the side opposite to the side on which the bottom wall portion is located in the growth direction of the single crystal, and suppresses heat dissipation from the seed crystal side held by the holding portion; A crucible. A lid that is connected to the peripheral wall and closes the other opening of the peripheral wall;
The lid portion is provided with a gap at a position overlapping the seed crystal held in the holding portion when viewed in plan from the growth direction of the single crystal,
The crucible according to claim 1, wherein the heat dissipation suppressing member is disposed in the gap. The holding portion has a pedestal first surface to which the seed crystal is attached, and a pedestal second surface located on the opposite side of the pedestal first surface in the growth direction of the single crystal, and the pedestal first surface is the bottom Including a pedestal disposed at a position facing the wall,
The crucible according to claim 1 or 2, wherein the heat dissipation suppressing member is disposed at a distance from the pedestal portion in the growth direction of the single crystal. The holding part includes an extension part extending in a cylindrical shape in a space surrounded by the peripheral wall part toward the bottom wall part, and having a wall surface on the inner side,
The crucible according to claim 1 or 2, wherein the extension portion holds the seed crystal on the wall surface. The heat dissipation suppressing member includes a first region located in the center when viewed in plan from the growth direction of the single crystal, and a second region located on the outer side from the first region,
The crucible according to any one of claims 1 to 4, wherein a distance between the first region and the seed crystal in a growth direction of the single crystal is shorter than a distance between the second region and the seed crystal. . The heat dissipation suppressing member includes a first heat dissipation adjustment region in which a distance from the seed crystal in the growth direction of the single crystal becomes longer as the distance from the seed crystal in the growth direction of the single crystal becomes closer to the outer side as viewed in plan from the growth direction of the single crystal. The crucible according to any one of claims 5 to 6. A crucible used for growing a silicon carbide single crystal by a sublimation method,
A cylindrical peripheral wall,
A bottom wall connected to the peripheral wall and closing one opening of the peripheral wall;
A rod-shaped portion extending into the space surrounded by the peripheral wall portion toward the bottom wall portion;
A holding part that is connected to an end of the rod-like part on the bottom wall part side and holds a seed crystal in a space surrounded by the peripheral wall part;
A heat dissipation suppressing member that is disposed at a distance from the seed crystal on the side opposite to the side on which the bottom wall portion is located in the growth direction of the single crystal, and suppresses heat dissipation from the seed crystal side held by the holding portion; A crucible. The heat dissipation suppressing member is connected to the rod-shaped portion, and includes a second heat dissipation adjustment region in which a distance from the holding portion in the growth direction of the single crystal increases as the rod-shaped portion is approached. Crucible. The crucible according to any one of claims 1 to 8, wherein the heat dissipation suppressing member includes a region extending obliquely with respect to a growth direction of the single crystal. The crucible according to any one of claims 1 to 9, wherein a plurality of the heat dissipation suppressing members are provided at intervals in the growth direction of the single crystal. The crucible according to any one of claims 1 to 10, wherein the heat dissipation suppressing member is made of graphite.

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