JP2012240906A - Apparatus for manufacturing silicon carbide single crystal, and method for manufacturing the silicon carbide single crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing a silicon carbide single crystal, which can manufacture a high quality and long silicon carbide single crystal, and to provide a method for manufacturing the silicon carbide single crystal.SOLUTION: In the apparatus for manufacturing the silicon carbide single crystal, a silicon carbide single crystal 71 is grown on a silicon carbide seed crystal 35 attached to a pedestal 33 in a crucible 31 by supplying a raw material gas onto the growth surface 35a of the silicon carbide seed crystal 35. The apparatus is configured so as to reduce the thickness of the pedestal 33, and the thickness of the pedestal 33 is reduced in accordance with the growth of the silicon carbide single crystal 71.

Description

  The present invention relates to a silicon carbide single crystal manufacturing apparatus and a method for manufacturing a silicon carbide single crystal.

  Silicon carbide (SiC) is one of the semiconductor materials and has a larger band gap than other semiconductor materials such as silicon (Si) and gallium arsenide (GaAs). Research has been conducted to form silicon carbide devices such as power devices, high-frequency devices, and high-temperature operating devices.

  The silicon carbide substrate is formed, for example, by slicing a silicon carbide single crystal ingot formed by a sublimation recrystallization method and then mirror-treating both surfaces. Further, the silicon carbide single crystal ingot is formed using a silicon carbide single crystal manufacturing apparatus (see, for example, Patent Documents 1 and 2).

FIG. 25 is a cross sectional view showing a main portion of a conventional silicon carbide single crystal manufacturing apparatus. In FIG. 25, X ₁ indicates a distance from the upper surface 205 a of the pedestal 205 to the growth surface 206 a (crystal front surface) of the silicon carbide seed crystal 206 (hereinafter referred to as “distance X ₁ ”).

  Referring to FIG. 25, conventional silicon carbide single crystal manufacturing apparatus 200 is integrally formed with crucible 202 that contains silicon carbide raw material 201, lid 204, and lid 204, and protrudes from lower surface 204 a of lid 204. And a silicon carbide seed crystal 206 on which a silicon carbide single crystal 208 is formed (see, for example, Patent Document 3).

  Normally, when silicon carbide single crystal 208 is formed using silicon carbide single crystal manufacturing apparatus 200, crystal growth surface 208a of silicon carbide single crystal 208 is previously convex (the upper surface of silicon carbide raw material 201) as shown in FIG. The optimum crystal growth conditions such that the surface is convex toward the 201a side are obtained, and the silicon carbide single crystal 208 is grown under the optimum crystal growth conditions.

  As described above, the silicon carbide single crystal 208 with few crystal defects can be obtained by growing the silicon carbide single crystal 208 so that the crystal growth surface 208a of the silicon carbide single crystal 208 becomes a convex surface (for example, patents). Reference 4).

JP 2002-308697 A Japanese Patent No. 4499698 JP 2009-23880 A JP-A-6-227886

  FIG. 26 and FIG. 27 are cross-sectional views for illustrating problems of a conventional silicon carbide single crystal manufacturing apparatus. 26 schematically shows a state in which silicon carbide single crystal 208 shown in FIG. 25 is further grown, and FIG. 27 schematically shows a state in which silicon carbide single crystal 208 shown in FIG. 26 is further grown. Yes.

In FIG. 26, X ₂ indicates the distance from the upper surface 205 a of the pedestal 205 to the crystal growth surface 208 _b of the silicon carbide single crystal 208 (hereinafter referred to as “distance X ₂ ”). Further, in FIG. 27, X ₃ indicates a distance from the upper surface 205a of the pedestal 205 to the crystal growth surface 208c of the silicon carbide single crystal 208 (hereinafter referred to as “distance X ₃ ”).
26 and 27, the same components as those of silicon carbide single crystal manufacturing apparatus 200 shown in FIG.

By the way, during the growth of the silicon carbide single crystal 208, the heat of the structure 211 composed of the pedestal 205, the silicon carbide seed crystal 206, and the silicon carbide single crystal 208 shown in FIGS. 26 and 27 is dissipated from the upper surface 205 a of the pedestal 205. Is done.
However, when the silicon carbide single crystal 208 advances, the distances X ₂ and X ₃ from the upper surface 205a of the pedestal 205 to the crystal growth surfaces 208b and 208c of the silicon carbide single crystal 208 become longer than the distance X ₁ . It becomes difficult to release heat.

  In other words, in the initial stage of growth, the first structure including the pedestal 205 and the silicon carbide seed crystal 206 has a thermal resistance, but when the growth of the silicon carbide single crystal 208 proceeds, the pedestal 205, the silicon carbide seed crystal 206, and Since the second structure formed of the silicon carbide single crystal 208 has a thermal resistance, the thermal resistance increases from the initial growth stage by the amount of the grown silicon carbide single crystal 208 when the growth of the silicon carbide single crystal 208 progresses. As a result, the heat dissipation capability from the upper surface 205a of the pedestal 205 is reduced.

  For this reason, when the growth of the silicon carbide single crystal proceeds, the temperature distribution on the crystal growth surface of the silicon carbide single crystal becomes different from the temperature distribution on the crystal growth surface of the silicon carbide single crystal at the initial growth stage.

  Further, when the growth of silicon carbide single crystal 208 further proceeds, the crystal growth surface approaches the surface of the silicon carbide raw material as a heat source, which also affects the temperature distribution on the crystal growth surface.

  Thus, since the temperature distribution on the crystal growth surface at the initial stage of growth changes with the growth of the silicon carbide single crystal, there has been a problem that the silicon carbide single crystal cannot be grown long under optimum crystal growth conditions.

In addition, if the silicon carbide single crystal is elongated, the silicon carbide single crystal cannot be grown under optimum crystal growth conditions, so that the crystal growth surface becomes concave and contains defects, or the crystal growth surface becomes convex. There was a problem of cracking.
That is, the conventional silicon carbide single crystal manufacturing apparatus cannot manufacture a silicon carbide single crystal (silicon carbide single crystal ingot) that has few crystal defects, is high quality, and is long.

  Accordingly, an object of the present invention is to provide a silicon carbide single crystal manufacturing apparatus and a silicon carbide single crystal manufacturing method capable of manufacturing a high quality and long silicon carbide single crystal with few crystal defects. And

  As a result of intensive studies in order to solve the above problems, the present inventor has reduced the thickness of the pedestal in order to produce a silicon carbide single crystal having few crystal defects, high quality, and a long length. The present inventors have conceived that it is necessary to reduce the thickness of the pedestal in accordance with the growth of the silicon carbide single crystal and the configuration capable of being reduced.

  Specifically, a pedestal before the silicon carbide single crystal is grown (a pedestal before the thickness is reduced), and the thickness of the first structure made of the silicon carbide seed crystal, and the pedestal with the thickness reduced, By making the thicknesses of the silicon carbide seed crystal and the second structure made of the silicon carbide single crystal as equal as possible, the change in the heat dissipation state of the first and second structures during crystal growth is reduced, and the carbonization It was thought that the change in temperature distribution on the crystal growth surface of the silicon single crystal can be reduced.

  As a result, the silicon carbide single crystal is grown under conditions that are close to the optimum crystal growth conditions (specifically, conditions in which the crystal growth surface is convex and crystal defects are less likely to occur) at the initial growth stage of the silicon carbide single crystal. It came to the idea that would be possible.

  Therefore, the present inventor performed a simulation for confirming how the difference in the thickness of the pedestal affects the temperature of the crystal growth surface of the silicon carbide single crystal. The result is shown in FIG.

FIG. 28 is a diagram showing a result of evaluating the relationship between the thickness of the pedestal and the temperature distribution on the crystal growth surface of the silicon carbide single crystal by simulation.
In FIG. 28, the temperature distribution of crystal growth surface 208a of silicon carbide single crystal 208 when sample silicon carbide single crystal 208 is formed in silicon carbide single crystal manufacturing apparatus 200 shown in FIG. Show.
In FIG. 28, as sample 2, temperature distribution of crystal growth surface 208b of silicon carbide single crystal 208 when silicon carbide single crystal 208 having a thickness of 10 mm is formed in silicon carbide single crystal manufacturing apparatus 200 shown in FIG. Indicates.

  Further, as Sample 3, a counterbore (a not-shown recess) is formed on pedestal 205 of silicon carbide single crystal manufacturing apparatus 200 shown in FIG. 27, and the thickness of pedestal 205 is reduced and a 10 mm thick silicon carbide single crystal is formed. The temperature distribution of the crystal growth surface 208c of the silicon carbide single crystal 208 when the crystal 208 is formed is shown.

In FIG. 28, the temperature in the radial direction of crystal growth surfaces 208a, 208b, 208c is shown with the temperature at the center of crystal growth surfaces 208a, 208b, 208c of silicon carbide single crystal 208 as the reference (0 ° C.).
In the above simulation, the simulation conditions were such that the thickness of the base 205 before the counterbore was formed was 10 mm, and the thickness of the base 205 after the counterbore was formed was 1 mm.

Referring to FIG. 28, it was confirmed from the results of the temperature distribution of samples 1 and 2 that a difference in temperature distribution between sample 1 and sample 2 occurred as the growth of silicon carbide single crystal 208 progressed.
Further, from the results of Sample 3, the temperature distribution in the radial direction of the crystal growth surface 208a on which 10 mm of the silicon carbide single crystal 208 is formed by forming counterbore and reducing the thickness of the pedestal 205 is shown in Sample 1. It was confirmed that the temperature distribution approached the initial crystal growth.

  In other words, from the above simulation results, by reducing the thickness of the pedestal according to the growth of the silicon carbide single crystal, the optimal crystal growth conditions (specifically, the crystalline growth surface) It was confirmed that the silicon carbide single crystal can be grown during the period from the start to the end of the growth of the silicon carbide single crystal under a condition close to a convex surface where crystal defects are less likely to occur.

Furthermore, as the growth of the silicon carbide single crystal 208 progresses, the influence of the temperature distribution on the crystal growth surface due to the crystal growth surface approaching the surface 201a of the silicon carbide raw material 201 is as follows. Adopting a configuration in which the distance between the crystal growth surface of the silicon carbide single crystal 208 and the surface 201a of the silicon carbide raw material 201 can be adjusted by using the separated crucible and relatively moving the upper crucible and the lower crucible; did.
As a result of further research on this finding, the present inventor has completed the present invention having the following means.

That is, in order to achieve the above object, the present invention provides the following means.
(1) A silicon carbide single crystal manufacturing apparatus for supplying a source gas to a growth surface of a silicon carbide seed crystal attached to a pedestal in a crucible and growing the silicon carbide single crystal on the silicon carbide seed crystal, The pedestal has a configuration capable of reducing the thickness of the pedestal.
(2) The pedestal is disposed on an upper end of the crucible, and the source gas obtained by sublimating the silicon carbide source is supplied to the growth surface of the silicon carbide seed crystal, thereby growing the silicon carbide single crystal. The silicon carbide single crystal manufacturing apparatus as described in (1) above.
(3) The carbonization according to (1) or (2) above, wherein the pedestal includes a pedestal body to which the silicon carbide seed crystal is attached and a plurality of plate members stacked on the pedestal body. Silicon single crystal manufacturing equipment.
(4) The pedestal main body is provided on a lid disposed at an upper end of the crucible, and the pedestal main body projects from a lower surface of the lid toward the upper surface of the silicon carbide raw material, and The apparatus for producing a silicon carbide single crystal as described in (3) above, further comprising a housing portion that houses at least one plate member.
(5) The silicon carbide single crystal manufacturing apparatus according to (4), wherein the housing part houses the plurality of plate members so as not to protrude from the upper surface of the lid.
(6) The silicon carbide single crystal manufacturing apparatus according to (4), wherein the housing portion and the plurality of plate members are stacked on the housing portion so as to protrude from the upper surface of the lid.
(7) The silicon carbide single crystal manufacturing apparatus according to any one of (3) to (6), wherein the pedestal body is integrated with the lid.
(8) The silicon carbide single crystal manufacturing apparatus according to any one of (1) to (7), wherein the crucible is provided with a guide member for guiding the source gas to the silicon carbide seed crystal side.
(9) In the preceding item (8), the guide member is a plate material substantially parallel to the upper surface of the silicon carbide raw material, and has an opening that exposes the growth surface of the silicon carbide seed crystal. ) Silicon carbide single crystal production apparatus.
(10) The silicon carbide single unit as described in (8) above, wherein the guide member has a cylindrical portion that exposes a growth surface of the silicon carbide seed crystal at a position below the silicon carbide seed crystal. Crystal manufacturing equipment.
(11) The silicon carbide single crystal manufacturing apparatus according to (10), wherein the cylindrical portion has the same width in a direction from the growth surface of the silicon carbide seed crystal toward the upper surface of the silicon carbide raw material. .
(12) The silicon carbide single crystal manufacturing apparatus according to (10), wherein the cylindrical portion has a wider shape from the growth surface of the silicon carbide seed crystal toward the upper surface of the silicon carbide raw material. .
(13) The crucible includes an upper crucible in which the lid is disposed, and a lower crucible containing the silicon carbide raw material, and the upper crucible and the lower crucible are relatively relative to the vertical direction. The silicon carbide single crystal manufacturing apparatus according to any one of (1) to (12), wherein the apparatus is movable.
(14) The silicon carbide single crystal manufacturing apparatus according to (13), wherein the guide member is provided on an inner wall of the upper crucible.
(15) The silicon carbide single crystal manufacturing apparatus according to any one of (1) to (14), wherein the material of the base is silicon carbide.
(16) The silicon carbide single crystal manufacturing apparatus according to any one of (1) to (14), wherein the material of the pedestal is carbon.
(17) A method for producing a silicon carbide single crystal in which a raw material gas is supplied to a growth surface of a silicon carbide seed crystal attached to a pedestal in a crucible and a silicon carbide single crystal is grown on the silicon carbide seed crystal. A method for producing a silicon carbide single crystal, comprising reducing the thickness of the pedestal as the silicon carbide single crystal grows.
(18) The pedestal is disposed at an upper end of the crucible so that the silicon carbide seed crystal faces the silicon carbide raw material housed in the crucible, and the silicon carbide raw material is formed on the growth surface of the silicon carbide seed crystal. The method for producing a silicon carbide single crystal as described in (17) above, wherein the silicon carbide single crystal is grown by supplying a raw material gas obtained by sublimating.
(19) The method for producing a silicon carbide single crystal as described in (17) or (18) above, wherein the thickness of the pedestal is reduced during the growth of the silicon carbide single crystal.
(20) The paragraph (17) or (18) above, wherein after the growth of the silicon carbide single crystal is stopped, the thickness of the pedestal is reduced, and then the silicon carbide single crystal is further grown. A method for producing a silicon carbide single crystal.
(21) The pedestal has a pedestal main body to which the silicon carbide seed crystal is attached, and a plurality of plate members stacked on the pedestal main body, and the thickness of the pedestal is reduced by removing the plate material. The method for producing a silicon carbide single crystal according to any one of (18) to (20), wherein the silicon carbide single crystal is thinned.
(22) The pedestal main body is provided in a lid disposed at an upper end of the crucible, protrudes in a direction from the lower surface of the lid toward the upper surface of the silicon carbide raw material, and accommodates the plate material. The silicon carbide single crystal according to (21), wherein the silicon carbide single crystal is grown after accommodating the plurality of plate members in the accommodating portion so as not to protrude from the upper surface of the lid. Crystal production method.
(23) The pedestal main body is provided in a lid disposed at an upper end of the crucible, protrudes in a direction from the lower surface of the lid toward the upper surface of the silicon carbide raw material, and accommodates the plate material And stacking the plurality of plate members on the housing portion and the housing portion so as to protrude from the upper surface of the lid, and then growing the silicon carbide single crystal on the silicon carbide seed crystal. The manufacturing method of the silicon carbide single crystal of the preceding clause (21).
(24) The pedestal is provided on a lid disposed at an upper end of the crucible, and the pedestal is disposed so as to project from an upper surface of the lid, and projects from an upper surface of the lid. The method for producing a silicon carbide single crystal according to any one of (18) to (20), wherein the thickness of the pedestal is reduced by cutting a part of the pedestal.
(25) When the silicon carbide seed crystal is grown, adjustment is made so that the distance between the upper surface of the silicon carbide raw material and the crystal growth surface of the silicon carbide single crystal is substantially equal. The method for producing a silicon carbide single crystal according to any one of (24).

  According to the silicon carbide single crystal manufacturing apparatus of the present invention, the pedestal before the silicon carbide single crystal is grown (the pedestal before the thickness is reduced) by adopting a configuration capable of reducing the thickness of the pedestal. And the thickness of the first structure made of the silicon carbide seed crystal and the thickness of the second structure made of the thin base, the silicon carbide seed crystal, and the silicon carbide single crystal as much as possible. It becomes possible.

  Thereby, the heat dissipation characteristic of the first structure that radiates heat from the upper surface of the pedestal before the thickness is reduced, and the heat dissipation characteristic of the second structure that radiates heat from the upper surface of the pedestal whose thickness is reduced. Therefore, the change in the temperature distribution on the crystal growth surface of the silicon carbide single crystal during growth can be reduced.

  That is, the silicon carbide single crystal is grown under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal (specifically, conditions in which the crystal growth surface is convex and crystal defects are less likely to occur). Is possible. Thereby, a silicon carbide single crystal having few crystal defects, high quality, and long length can be manufactured.

  In addition, according to the method for producing a silicon carbide single crystal of the present invention, by reducing the thickness of the pedestal as the silicon carbide single crystal grows, the optimum crystal growth conditions (specifically, the initial stage of the growth of the silicon carbide single crystal). Specifically, it is possible to grow a silicon carbide single crystal under conditions close to a condition in which the crystalline growth surface is convex and crystal defects are less likely to occur. Thereby, a silicon carbide single crystal having few crystal defects, high quality, and long length can be manufactured.

It is sectional drawing which shows schematic structure of the silicon carbide single crystal manufacturing apparatus which concerns on the 1st Embodiment of this invention. It is sectional drawing to which the silicon carbide single crystal manufacturing apparatus main body shown in FIG. 1 was expanded. It is a perspective view of a 1st board | plate material and a base thickness adjustment member. It is sectional drawing which shows the state which the ceiling surface of the hook accommodating part and the 1st hook part of the base thickness adjustment member contacted. It is a perspective view of a 2nd board | plate material and a base thickness adjustment member. It is sectional drawing which shows the state which the ceiling surface of the hook accommodating part and the 2nd hook part of the base thickness adjustment member contacted. It is sectional drawing which shows typically the silicon carbide single-crystal manufacturing apparatus main body of the state in which the 1st board | plate material contacted the base main body, and the 2nd board | plate material was pulled up above the 1st board | plate material. It is sectional drawing which shows typically the silicon carbide single crystal manufacturing apparatus main body of the state by which the 1st board | plate material was pulled up above the base main body. It is sectional drawing of the principal part of the silicon carbide single crystal manufacturing apparatus which concerns on the 1st modification of the 1st Embodiment of this invention. It is sectional drawing of the principal part of the silicon carbide single crystal manufacturing apparatus which concerns on the 2nd modification of the 1st Embodiment of this invention. It is sectional drawing of the principal part of the silicon carbide single crystal manufacturing apparatus which concerns on the 3rd modification of the 1st Embodiment of this invention. It is sectional drawing of the principal part of the silicon carbide single crystal manufacturing apparatus which concerns on the 4th modification of the 1st Embodiment of this invention. It is sectional drawing which shows schematic structure of the silicon carbide single crystal manufacturing apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows schematic structure of the silicon carbide single crystal manufacturing apparatus which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows typically the silicon carbide single crystal manufacturing apparatus provided with the base cut | disconnected in the 1st cutting position. It is sectional drawing which shows typically the silicon carbide single crystal manufacturing apparatus provided with the base cut | disconnected in the 2nd cutting position. It is sectional drawing (the 1) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 2) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 3) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 4) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 5) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 6) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 7) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing (the 8) which shows the manufacturing process of the silicon carbide single crystal which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows the principal part of the conventional silicon carbide single crystal manufacturing apparatus. It is sectional drawing (the 1) for demonstrating the problem of the conventional silicon carbide single crystal manufacturing apparatus. It is sectional drawing (the 2) for demonstrating the problem of the conventional silicon carbide single crystal manufacturing apparatus. It is a figure which shows the result of having evaluated the relationship between the thickness of a base, and the temperature distribution of the crystal growth surface of a silicon carbide single crystal by simulation.

  Embodiments to which the present invention is applied will be described below in detail with reference to the drawings. The drawings used in the following description are for explaining the configuration of the embodiment of the present invention, and the size, thickness, dimensions, etc. of each part shown in the drawings are the dimensional relationships of an actual silicon carbide single crystal manufacturing apparatus. May be different.

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of the silicon carbide single crystal manufacturing apparatus according to the first embodiment of the present invention. In FIG. 1, as an example of a silicon carbide single crystal manufacturing apparatus, a silicon carbide single crystal 35 is supplied to a silicon carbide seed crystal 35 by supplying a source gas obtained by sublimating a silicon carbide raw material 39 to a growth surface 35 a of the silicon carbide seed crystal 35. Silicon carbide single crystal manufacturing apparatus 10 for growing crystal 71 (in other words, silicon carbide single crystal manufacturing apparatus for growing silicon carbide single crystal 71 by a sublimation recrystallization method) will be described as an example.

  Referring to FIG. 1, a silicon carbide single crystal manufacturing apparatus 10 according to a first embodiment includes a vacuum vessel 11, a heat insulating member 12, a silicon carbide single crystal manufacturing apparatus main body 13, a support member 15, and heating means. 16, and first and second radiation thermometers 18 and 19.

The vacuum vessel 11 contains a heat insulating member 12, a silicon carbide single crystal manufacturing apparatus main body 13, and a support member 15. The vacuum vessel 11 has a gas introduction hole 22 and a gas discharge hole 23.
The gas introduction hole 22 is connected to an Ar gas supply device (not shown). By supplying Ar gas into the vacuum vessel 11, an Ar atmosphere (for example, a pressure of 5.0 × 10 ² Pa).
The gas discharge hole 23 is connected to a vacuum pump (not shown), and the inside of the vacuum vessel 11 is brought into a reduced pressure state before supplying the Ar gas. The pressure in the vacuum vessel 11 in a reduced pressure state can be set to 4 × 10 ⁻³ Pa or less, for example.

The heat insulating member 12 is disposed in the vacuum container 11. The heat insulating member 12 includes an apparatus main body accommodating portion 25, a penetrating portion 26, and a window hole 27. The apparatus main body accommodating portion 25 is provided inside the heat insulating member 12.
In a state where the silicon carbide single crystal manufacturing apparatus main body 13 is accommodated in the apparatus main body accommodating portion 25, the upper portion of the heat insulating member 12 is disposed at a position spaced above the lid body 32. Thereby, when the 2nd board | plate material 52 (one of the component of the base 33) mentioned later is pulled up between the upper part of the heat insulation member 12 and the cover body 32, the 2nd board | plate material 52 pulled up is arrange | positioned. A possible space is formed.

The through portion 26 is provided so as to penetrate a portion of the heat insulating member 12 located above the apparatus main body housing portion 25. The penetrating portion 26 has an opening diameter capable of pulling up a column portion 64 of a pedestal thickness adjusting member 36 described later and capable of measuring the temperature of the lid 32 by the first radiation thermometer 18. Since the temperature of the upper part of the crucible 31 will fall too much when the opening diameter of the opening part 26 is large, it is preferable that the opening diameter of the opening part 26 is small.
The window hole 27 is provided so as to penetrate a portion of the heat insulating member 12 located below the apparatus main body housing portion 25.

The heat insulating member 12 configured as described above is a member for stably keeping the temperature in the crucible 31 described later by accommodating the silicon carbide single crystal manufacturing apparatus main body 13. As a material of the heat insulating member 12, for example, carbon fiber can be used.
In addition, when the temperature in the crucible 31 can be stably kept at a high temperature, the heat insulating member 12 does not need to be provided.

FIG. 2 is an enlarged cross-sectional view of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG. Further, FIG. 2 schematically shows a silicon carbide single crystal 71 at the initial stage of growth.
1 and 2, a silicon carbide single crystal manufacturing apparatus main body 13 includes a crucible 31, a lid 32, a pedestal 33, a silicon carbide seed crystal 35, a plate material pulling member 36, and a plate material pulling material. It has a member drive part (not shown) and an upper crucible raising / lowering means 38.

  Referring to FIG. 2, the crucible 31 includes a lower crucible 41 and an upper crucible 42. Lower crucible 41 contains silicon carbide raw material 39. The lower crucible 41 has a slide part 43 having a slide surface 43a at the upper end. The slide surface 43 a is a surface corresponding to the outer peripheral side surface of the slide portion 43.

The upper crucible 42 has a cylindrical shape, and has a slide portion 44 having a slide surface 44a at the lower end thereof. The upper crucible 42 is disposed on the lower crucible 41 so that the slide surface 44 a contacts the slide surface 43 a of the lower crucible 41.
The slide surface 44a is configured to be slidable in the vertical direction with respect to the slide surface 43a. That is, the upper crucible 42 is configured to be movable (slidable) in the vertical direction with respect to the lower crucible 41.
In FIG. 2, the case where the volume of the space 46 formed in the crucible 31 is minimized is illustrated as an example.

  As a material for the crucible 31 having the above-described structure, it is preferable to use a material that is stable at a high temperature and generates little impurity gas. Specifically, as the material of the crucible 31, for example, graphite (graphite), silicon carbide, and graphite (graphite) coated with silicon carbide or tantalum carbide (TaC) can be used.

  Referring to FIG. 2, the lid 32 is disposed at the upper end of the upper crucible 42. The lid 32 is formed with a penetrating portion 32 </ b> A having a shape capable of taking out first and second plate members 51 and 52, which will be described later, constituting the base 33. The lid 32 has an upper surface 32a and a lower surface 32b that are flat surfaces.

Referring to FIG. 2, the pedestal 33 includes a pedestal main body 48 and first and second plate members 51 and 52 that are a plurality of plate members stacked on the upper surface 48 a of the pedestal main body 48.
The pedestal main body 48 includes an accommodating portion 54 that accommodates the first and second plate members 51 and 52. The pedestal main body 48 is fixed to the lower surface 32b of the lid body 32 so that the accommodating portion 54 is exposed to the penetration portion 32A. Pedestal main body 48 protrudes from lower surface 32 b of lid body 32 in a direction toward upper surface 39 a of silicon carbide raw material 39.

  The accommodating part 54 accommodates the first and second plate members 51 and 52 so as not to protrude from the upper surface 32 a of the lid 32. In FIG. 2, the case in which the accommodating portion 54 accommodates the first and second plate members 51 and 52 is illustrated as an example, but the accommodating portion 54 has a configuration capable of accommodating at least one plate member. Good.

FIG. 3 is a perspective view of the first plate member and the pedestal thickness adjusting member. FIG. 4 is a cross-sectional view showing a state in which the ceiling surface of the hook housing portion and the first hook portion of the pedestal thickness adjusting member are in contact with each other.
Referring to FIG. 2, the first plate member 51 has a substantially cylindrical shape. The first plate member 51 is disposed in the accommodating portion 54 so as to come into contact with the upper surface 48 a of the pedestal main body 48.

Referring to FIG. 3, the first plate member 51 includes a hook housing portion 56, a support column passage portion 57, and a hook passage portion 58. The hook accommodating portion 56 is formed inside the first plate member 51. The hook accommodating portion 56 is a cylindrical space having a diameter wider than the length J1 of the _first hook portion 65 provided in the plate material lifting member 36.

  3 is moved downward, the first hook portion 65 is accommodated in the hook accommodating portion 56, and then the first hook portion 65 is rotated by 90 degrees, so that the plate material lifting member 36 is moved. As shown in FIG. 4, the first hook portion 65 comes into contact with the ceiling surface 56a of the hook accommodating portion 56, and the plate member lifting member 36 is further lifted upward to raise the base shown in FIG. The first plate member 51 can be lifted above the main body 48. In other words, the first plate member 51 can be removed from the pedestal main body 48.

Referring to FIG. 3, the support column passage portion 57 is formed so as to penetrate the first plate member 51 located on the hook accommodating portion 56. The strut portion passage portion 57 is a cylindrical space having a diameter larger than the diameter of the strut portion 64 constituting the plate material lifting member 36 and smaller than the length J _{1 of} the first hook portion 65. The support part passage part 57 is a space for allowing the column part 64 to pass therethrough.

  Referring to FIG. 3, the hook passage portion 58 is formed so as to penetrate the first plate member 51 located on the hook housing portion 56. The hook passage portion 58 is a rectangular column-shaped groove, and is configured integrally with the hook housing portion 56 and the column portion passage portion 57. The hook passage portion 58 is a space for allowing the first hook portion 65 to pass therethrough. The thickness of the first plate member 51 having the above configuration can be set to, for example, 20 mm.

FIG. 5 is a perspective view of the second plate member and the pedestal thickness adjusting member. FIG. 6 is a cross-sectional view showing a state in which the ceiling surface of the hook housing portion and the second hook portion of the pedestal thickness adjusting member are in contact with each other.
Referring to FIG. 5, the second plate member 52 is provided with a strut portion passage portion 61 and a hook passage portion 62 in addition to the configuration of the first plate member 51, and a hook housing portion provided on the first plate member 51. The configuration is the same as that of the first plate member 51 except that the height of the hook accommodating portion 56 is made lower than that of the first plate member 51. The thickness of the 2nd board | plate material 52 is equal to the thickness of the 1st board | plate material 51, for example, can be 20 mm.

  Referring to FIG. 2, the second plate member 52 is accommodated in the accommodating portion 54 and the penetrating portion 32A. The upper surface 52 a of the second plate member 52 is substantially flush with the upper surface 32 a of the lid 32. In other words, the accommodating part 54 accommodates the first and second plate members 51 and 52 (a plurality of plate members) so as not to protrude from the upper surface 32 a of the lid 32.

Referring to FIGS. 5 and 6, the support column passage portion 61 is formed so as to penetrate the second plate member 52 located below the hook accommodating portion 56. The column portion passage portion 61 is a space for allowing the column portion 64 to pass therethrough, and has the same shape as the column portion passage portion 57.
Referring to FIG. 5, the hook passage portion 62 is formed so as to penetrate the second plate member 52 located below the hook housing portion 56. The hook passage portion 62 is a space for allowing the first hook portion 65 to pass therethrough and has the same shape as the hook passage portion 58.

  5 is moved downward, the second hook portion 66 is accommodated in the hook accommodating portion 56 of the second plate material 52, and then the second hook portion 66 is rotated 90 degrees, By pulling up the plate material lifting member 36, the second hook portion 66 comes into contact with the ceiling surface 56a of the hook housing portion 56 and the plate material lifting member 36 is pulled upward as shown in FIG. 2, the second plate member 52 can be lifted above the pedestal main body 48 to remove the second plate member 52 from the first plate member 51.

  FIG. 7 is a cross-sectional view schematically showing the silicon carbide single crystal manufacturing apparatus main body in a state in which the first plate material is in contact with the pedestal main body and the second plate material is pulled up above the first plate material. In FIG. 7, the same components as those of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG. In FIG. 7, the upper crucible lifting / lowering means 38 shown in FIG. 2 is not shown. Further, FIG. 7 schematically shows silicon carbide single crystal 71 in a state of growing from silicon carbide single crystal 71 shown in FIG.

  By the way, the height of the hook accommodating portion 56 of the second plate material 52 is configured to be lower than the height of the hook accommodating portion 56 of the first plate material 51. For this reason, when the plate member lifting member 36 is pulled up, the second hook portion 66 comes into contact with the ceiling surface 56 a of the hook accommodating portion 56 before the first hook portion 65.

  As a result, as shown in FIG. 7, the second plate material 52 is lifted prior to the first plate material 51 by pulling up the plate material lifting member 36, and the first plate material 51 comes into contact with the base body 48. In the state, a gap is formed between the first plate member 51 and the second plate member 52. In other words, the second plate material 52 is removed from the first plate material 51.

  In this case, the pedestal 33 shown in FIG. 7 is composed of the pedestal main body 48 and the first plate member 51, and the thickness of the pedestal 33 shown in FIG. 7 is the pedestal 33 (the pedestal main body 48, the first plate member shown in FIG. 51 and the thickness of the pedestal formed by the second plate member 52.

Further, as shown in FIG. 7, the thickness M2 of the _second structure B made of the pedestal main body 48, the first plate member 51, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 is shown in FIG. When the thickness M _{1 of} the first structure A made of the pedestal 33 and the silicon carbide seed crystal 35 is substantially equal to the thickness of the pedestal 33, the second plate member 52 is separated above the first plate member 51. It is good to make it thin.

Thus, the thickness M ₁ of the first structure A shown in FIG. 2, the thickness M ₂ of the second structure B shown in FIG. 7, it becomes possible to be as equal as possible, FIG. 2 The heat dissipation characteristics of the first structure A that radiates heat from the upper surface of the pedestal 33 (in this case, the upper surface 52a of the second plate member 52) and the upper surface of the pedestal 33 shown in FIG. It is possible to reduce the difference from the heat dissipation characteristics of the second structural body B that dissipates heat from the upper surface 51a) of the plate material 51.

  Therefore, the difference between the temperature distribution of crystal growth surface 71a of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 2 and the temperature distribution of crystal growth surface 71b of silicon carbide single crystal 71 shown in FIG. 7 can be reduced. It becomes possible.

  That is, the crystal growth surface 71b is close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71 (specifically, conditions where the crystal growth surface 71a is convex and crystal defects are not likely to occur). It becomes possible to grow the silicon carbide single crystal 71 having a convex surface. Thereby, silicon carbide single crystal 71 with few crystal defects and high quality can be manufactured.

  FIG. 8 is a cross-sectional view schematically showing the silicon carbide single crystal manufacturing apparatus main body in a state where the first plate member is pulled up above the pedestal main body. In FIG. 8, the same components as those of the silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG. FIG. 8 schematically shows a state in which silicon carbide single crystal 71 has grown further than silicon carbide single crystal 71 shown in FIG.

  As shown in FIG. 8, when the silicon carbide single crystal 71 grows further than the silicon carbide single crystal 71 shown in FIG. 7, the base body 48 is lifted by lifting the plate member lifting member 36 from the state shown in FIG. The first plate member 51 is removed from the pedestal 33 to reduce the thickness of the pedestal 33 shown in FIG. 8 (in this case, a pedestal composed only of the pedestal main body 48).

At this time, the thickness M _{3 of} the second structure C composed of the pedestal 33, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 shown in FIG. 8 is the thickness of the first structure A shown in FIG. When it becomes substantially equal to M ₁ , the thickness of the pedestal 33 may be reduced by separating the first plate member 51 above the pedestal main body 48.

Thereby, the thickness M _{1 of} the first structure A shown in FIG. 2 and the thickness M _{3 of} the second structure C shown in FIG. 8 can be made as equal as possible. The heat dissipation characteristics of the first structure A that radiates heat from the upper surface of the pedestal 33 (in this case, the upper surface 52a of the second plate member 52), and the upper surface of the pedestal 33 shown in FIG. It is possible to reduce the difference from the heat dissipation characteristics of the second structure C that dissipates heat from the upper surface 48a).

  Therefore, the difference between the temperature distribution of crystal growth surface 71a of silicon carbide single crystal 71 shown in FIG. 2 and the temperature distribution of crystal growth surface 71c of silicon carbide single crystal 71 shown in FIG. 8 can be reduced. .

  That is, it becomes possible to grow the silicon carbide single crystal 71 having the crystal growth surface 71c as a convex surface under conditions close to the optimum crystal growth conditions at the initial growth stage of the silicon carbide single crystal 71. Thereby, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.

  As a material for the pedestal 33 shown in FIG. 2, for example, silicon carbide, carbon, or the like may be used. As a result, the difference in thermal expansion coefficient between silicon carbide seed crystal 35 and silicon carbide single crystal 71 is reduced, so that growing silicon carbide single crystal 71 is damaged due to the difference in thermal expansion coefficient. Can be suppressed.

  2, 7, and 8, the pedestal main body 48 and the lid 32 are illustrated as an example, but the pedestal main body 48 and the lid 32 are integrally configured. May be. In this case, as a material of the lid body 32, for example, silicon carbide, carbon, or the like may be used.

  Referring to FIG. 2, silicon carbide seed crystal 35 is attached to lower surface 48 b of pedestal main body 48. Silicon carbide seed crystal 35 has a growth surface 35a on which silicon carbide single crystal 71 grows. Growth surface 35 a is arranged to face upper surface 39 a of silicon carbide raw material 39.

Referring to FIGS. 2 and 5, the plate material lifting member 36 includes a support column portion 64, a first hook portion 65, and a second hook portion 66. The support | pillar part 64 is made into the rod shape.
The first hook portion 65 is provided at the lower end of the column portion 64. The first hook portion 65 is accommodated in the hook accommodating portion 56 of the first plate member 51, and contacts the upper surface 56 a of the hook accommodating portion 56 when the first plate member 51 is pulled up.

  The second hook portion 66 is provided on the support column portion 64 positioned above the first hook portion 65. The second hook portion 66 is disposed so as to face the first hook portion 65. The second hook portion 66 is accommodated in the hook accommodating portion 56 of the second plate member 52, and contacts the upper surface 56 a of the hook accommodating portion 56 when the second plate member 52 is pulled up.

A plate material pulling member drive unit (not shown) is connected to the upper end of the column 64. A plate material lifting member drive unit (not shown) moves the plate material lifting member 36 in the vertical direction and rotates the plate material lifting member 36.
The plate material pulling member drive unit (not shown) moves the plate material pulling member 36 upward from the state shown in FIG. 2, so that the second plate material 52 or the first and second plate materials 51, 52 is pulled up to reduce the thickness of the pedestal 33.

Further, the plate member lifting member 36 moves the plate member lifting member 36 downward from the state shown in FIG. 8, thereby stacking the first and second plate members 51, 52 on the upper surface 48 a of the base body 48.
Note that the plate material lifting member 36 may be moved manually or the plate material lifting member 36 may be rotated manually without providing a plate material lifting member driving section (not shown).

Referring to FIG. 2, the upper crucible lifting / lowering means 38 includes a shaft portion 75, a shaft guide portion 76, and a drive portion 77.
The shaft portion 75 is provided below the lower crucible 41 and is connected to the bottom of the lower crucible 41. Thereby, the shaft portion 75 supports the lower crucible 41.

The shaft guide portion 76 is fixed to the slide portion 44 of the upper crucible 42. The shaft guide portion 76 has a shape that can contact the outer peripheral side surface 41 a of the lower crucible 41 and the outer peripheral side surface 75 a of the shaft portion 75. The shaft guide portion 76 is configured to be slidable in the vertical direction with respect to the outer peripheral side surface 41 a of the lower crucible 41 and the outer peripheral side surface 75 a of the shaft portion 75. The shaft guide part 76 moves the upper crucible 42 up and down by moving up and down.
The drive unit 77 is connected to the shaft guide unit 76. The drive unit 77 is a drive unit for moving the shaft guide unit 76 in the vertical direction.

Thus, the crucible 31 constituted by the lower crucible 41 and the upper crucible 42 configured to be movable in the vertical direction with respect to the lower crucible 41, and the upper crucible lifting / lowering means 38 for moving the upper crucible 42 in the vertical direction. And the distances D ₂ and D ₃ between the crystal growth surfaces 71b and 71c shown in FIGS. 7 and 8 and the upper surface 39a of the silicon carbide raw material 39 are the same as the crystal growth surface 71a and the silicon carbide raw material shown in FIG. 39 was adjusted to be substantially equal to the distance D ₁ of the and the upper surface 39a while it is possible to form a silicon carbide single crystal 71.

  Accordingly, the growth conditions of silicon carbide single crystal 71 shown in FIGS. 7 and 8 can be made closer to the growth conditions of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. A silicon carbide single crystal 71 having substantially uniform characteristics can be manufactured.

In FIG. 2, the case where the upper crucible 42 moves in the vertical direction with respect to the lower crucible 41 has been described as an example, but the upper crucible 42 and the lower crucible 41 can move relative to the vertical direction. Any configuration may be used.
Specifically, for example, instead of the upper crucible lifting / lowering means 38, a lower crucible lifting / lowering means (not shown) that fixes the position of the upper crucible 42 and moves the lower crucible 41 in the vertical direction with respect to the upper crucible 42 is provided. It may be provided.

  Referring to FIG. 1, the support member 15 has a cylindrical shape and has a through hole 15A. The support member 15 is disposed on the lower surface of the heat insulating member 12 so that the through hole 15 </ b> A faces the window hole 27 formed in the heat insulating member 12. As a result, the support member 15 supports the heat insulating member 12.

Referring to FIG. 1, the heating means 16 is disposed outside the vacuum vessel 11. The heating means 16 sublimates the source gas by heating the silicon carbide source 39 in the crucible 31.
As the heating means 16, for example, a high frequency heating coil that generates a high frequency by passing a current can be used.
Thus, by using a high frequency heating coil as the heating means 16, the silicon carbide raw material 39 can be heated to a temperature of 1900 ° C. or higher, for example.

  Referring to FIG. 1, the first radiation thermometer 18 is disposed above the vacuum vessel 11 so as to face the penetrating portion 26 formed in the heat insulating member 12. The first radiation thermometer 18 measures the temperature of the upper surface of the crucible 31 through the penetration part 26.

  Referring to FIG. 1, the second radiation thermometer 19 is disposed below the vacuum vessel 11 so as to face a through hole 15 </ b> A formed in the support member 15. The second radiation thermometer 19 measures the temperature of the lower surface of the crucible 31 through the through hole 15 </ b> A and the window hole 27.

  Note that the temperature of the upper surface and the lower surface of the crucible 31 may be measured using two thermocouples instead of the first and second radiation thermometers 18 and 19. In this case, one thermocouple is disposed so as to be in contact with the upper surface 32a of the lid body 32 through the through portion 26, and the other thermocouple is disposed in the crucible 31 through the through hole 15A and the window hole 27. Arrange it to contact the lower surface.

According to the silicon carbide single crystal manufacturing apparatus of the first embodiment, the pedestal main body 48 provided with the silicon carbide seed crystal 35 and the first and second plate members 51 and 52 stacked on the pedestal main body 48 are provided. By including the base 33, the second plate member 52, and the plate member lifting member 36 for pulling up the plate member in this order, the second plate member 52 or the first and second plate members 51 and 52 are provided. By pulling up and reducing the thickness of the pedestal 33, the thickness M1 of the _first structure A composed of the pedestal 33 (the pedestal before the thickness is reduced) and the silicon carbide seed crystal 35 are reduced. The thicknesses M ₂ and M _{3 of} the second structures B and C made of the pedestal 33, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 can be made as equal as possible.

  Thus, the heat dissipation characteristics of the first structure A that radiates heat from the upper surface of the pedestal 33 before the thickness is reduced, and the second structure that radiates heat from the upper surface of the pedestal 33 whose thickness is reduced. Since the difference between the heat dissipation characteristics of B and C becomes small, the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial stage of growth and the silicon carbide single crystal 71 when the growth of the silicon carbide single crystal 71 progresses. It is possible to reduce the difference between the temperature distribution of the crystal growth surfaces 71b and 71c.

  Therefore, the silicon carbide single crystal 71 is grown under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71 (specifically, conditions in which the crystal growth surface 71a is convex and crystal defects are less likely to occur). Therefore, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.

  In silicon carbide single crystal manufacturing apparatus 10 of the first embodiment, an example is given in which the volume of space 46 in crucible 31 can be changed by moving upper crucible 42 relative to lower crucible 41. As described above, the pedestal 33 and the plate member lifting member 36 described in the first embodiment include a crucible (a crucible 102 shown in FIG. 12 described later) in which the volume in the crucible cannot be changed. The present invention can also be applied to a silicon carbide single crystal manufacturing apparatus.

Next, with reference to FIGS. 2, 7, and 8, a method for manufacturing silicon carbide single crystal 71 of the first embodiment will be described.
First, as shown in FIG. 2, a silicon carbide raw material 39 is introduced into the lower crucible 41. Next, the silicon carbide seed crystal 35 is attached to the lower surface 48 b of the pedestal main body 48. Next, the lid 32 is disposed on the upper end of the upper crucible 42 so that the growth surface 35 a of the silicon carbide seed crystal 35 and the upper surface 39 a of the silicon carbide raw material 39 in the crucible 31 face each other.

Next, the first and second plate members 51 and 52 are stacked on the upper surface 48a of the pedestal main body 48 by moving the plate member lifting member 36 supporting the first and second plate members 51 and 52 downward (FIG. 2 is a state of the pedestal 33 shown in FIG.
At this time, the first and second plate members 51 and 52 are housed in the housing portion 54 of the pedestal main body 48 so that the second plate member 52 does not protrude from the upper surface 32 a of the lid 32. At this stage, as shown in FIG. 2, the volume of the space 46 in the crucible 31 is minimized.

  Next, the silicon carbide raw material 39 in the crucible 31 is heated by the heating means 16 shown in FIG. 1, so that the source gas is sublimated on the growth surface 35 a of the silicon carbide seed crystal 35, and the silicon carbide single crystal is formed on the growth surface 35 a. 71 is initially grown. At this time, the optimum crystal growth conditions acquired in advance (specifically, conditions under which the crystal growth surface 71a is a convex surface and crystal defects are not easily generated) are used.

Next, as shown in FIG. 7, when the thickness of the second plate 52 and the thickness of the silicon carbide single crystal 71 are substantially equal, the plate pulling member 36 is moved upward during crystal growth, 1 of the plate 51 by removing the second plate member 52, the thickness M ₂ of the second structure B shown in FIG. 7, the thickness M ₁ of the first structure a shown in FIG. 2, Are made as equal as possible, and the upper surface 51 a of the first plate member 51 is exposed from the second plate member 52.

  Thus, the heat dissipation characteristics of the first structure A that radiates heat from the upper surface of the pedestal 33 shown in FIG. 2 (in this case, the upper surface 52a of the second plate member 52), and the upper surface of the pedestal 33 shown in FIG. In this case, since the difference from the heat dissipation characteristics of the second structure B that dissipates heat from the upper surface 51a) of the first plate member 51 becomes small, the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial growth stage. And the temperature distribution on the crystal growth surface 71b of the silicon carbide single crystal 71 when the growth of the silicon carbide single crystal 71 proceeds can be reduced.

  This makes it possible to grow silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of growth of silicon carbide single crystal 71, so that there are crystal defects in silicon carbide single crystal 71 shown in FIG. It is possible to grow the silicon carbide single crystal 71 having a small amount and high quality.

In the case of forming a silicon carbide single crystal 71 shown in FIG. 7, the distance D ₂ from the crystal growth surface 71b of the silicon carbide single crystal 71 to the upper surface 39a of the silicon carbide source material 39, the distance D ₁ substantially as shown in FIG. 2 The upper crucible 42 is moved upward in accordance with the growth of the silicon carbide single crystal 71 so as to be equal.

  Accordingly, the growth conditions of silicon carbide single crystal 71 shown in FIG. 7 can be made closer to the growth conditions of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. Silicon carbide single crystal 71 having excellent characteristics can be formed.

Next, as shown in FIG. 8, the thickness of first plate member 51 and the thickness of silicon carbide single crystal 71 shown in FIG. 8 minus the thickness of silicon carbide single crystal 71 shown in FIG. At the stage where they are substantially equal, the plate member pulling member 36 is further moved upward during crystal growth to remove the first plate member 51 from the pedestal main body 48, whereby the thickness M _{3 of} the second structure C is obtained. 2 and the thickness M _{1 of} the first structure A shown in FIG. 2 are made as equal as possible, and the upper surface 48 a of the base body 48 is exposed from the first plate member 51.

  As a result, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The silicon carbide single crystal 71 can be grown.

In the case of forming a silicon carbide single crystal 71 shown in FIG. 8, the distance D ₃ from the crystal growth surface 71c of the silicon carbide single crystal 71 to the upper surface 39a of the silicon carbide source material 39, the distance D ₁ substantially as shown in FIG. 2 The upper crucible 42 is moved upward in accordance with the growth of the silicon carbide single crystal 71 so as to be equal.
Accordingly, the growth conditions of silicon carbide single crystal 71 shown in FIG. 8 can be made closer to the growth conditions of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. Silicon carbide single crystal 71 having excellent characteristics can be formed.

  According to the silicon carbide single crystal manufacturing method of the first embodiment, silicon carbide raw material 39 is sublimated by heating on growth surface 35a of silicon carbide seed crystal 35 attached to pedestal main body 48 constituting pedestal 33. By supplying the raw material gas, the silicon carbide single crystal 71 is grown, and during the growth of the silicon carbide single crystal 71, the second plate material 52 and the first plate material 51 according to the growth of the silicon carbide single crystal 71. By sequentially removing the silicon carbide single crystal 71, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71. A long silicon carbide single crystal 71 can be manufactured.

  Further, in the first embodiment, as an example, the case where the silicon carbide single crystal 71 is manufactured by the sublimation recrystallization method has been described. However, the present invention can be applied to, for example, silane or propane instead of the source gas (sublimation gas). The present invention can also be applied to a CVD (Chemical Vapor Deposition) method using, as a raw material.

In the manufacturing method of silicon carbide single crystal 71 according to the first embodiment, the case where the thickness of pedestal 33 is reduced during crystal growth has been described as an example. After stopping, the thickness of the pedestal 33 may be reduced, and then the silicon carbide single crystal 71 may be further grown.
As described above, when the growth of the silicon carbide single crystal 71 is stopped, and then the thickness of the pedestal 33 is reduced and then the silicon carbide single crystal 71 is further grown, the silicon carbide of the first embodiment is used. An effect similar to that of the manufacturing method of the single crystal 71 can be obtained.

  The method in which the growth of the silicon carbide single crystal 71 is once stopped and then the thickness of the pedestal 33 is reduced, and then the silicon carbide single crystal 71 is further grown is configured such that the volume in the crucible cannot be changed. This is effective when the silicon carbide single crystal 71 is formed by a sublimation recrystallization method using a silicon carbide single crystal manufacturing apparatus equipped with a crucible (a crucible 102 shown in FIG. 12 described later).

After the growth of the silicon carbide single crystal 71 is stopped, the distances D ₂ and D ₃ shown in FIGS. 7 and 8 are adjusted by adjusting the length of the lower crucible 41 or the upper crucible 42 or the amount of the silicon carbide raw material 39. This is because it can be substantially the same and the distance D ₁ shown in FIG. 2 and.

2 and 7, the thickness M ₁ and the thickness M ₂ are the same. However, depending on the thermal conductivity of the material used for the pedestal, for example, the first structure A shown in FIG. heat dissipation properties of the, as the heat dissipation characteristics of the second structure B shown in FIG. 7, are the same, may be set the value of the thickness of M _2.

FIG. 9 is a cross-sectional view of the main part of the silicon carbide single crystal manufacturing apparatus according to the first modification of the first embodiment of the present invention.
In FIG. 9, the vacuum vessel 11, the heat insulating member 12, the support member 15, the heating means 16, and the first radiation temperature, which are components of the silicon carbide single crystal manufacturing apparatus 80 according to the first modification of the first embodiment. Illustration of the total 18, the second radiation thermometer 19, and the upper crucible elevating means 38 (see FIGS. 1 and 2) is omitted. In FIG. 9, the same components as those of the structure shown in FIG.

Referring to FIG. 9, silicon carbide single crystal manufacturing apparatus 80 according to the first modification of the first embodiment is a silicon carbide single crystal provided in silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. It is comprised similarly to the silicon carbide single crystal manufacturing apparatus 10 except having provided the silicon carbide single crystal manufacturing apparatus main body 81 instead of the crystal manufacturing apparatus main body 13. FIG.
Silicon carbide single crystal manufacturing apparatus 81 is configured in the same manner as silicon carbide single crystal manufacturing apparatus main body 13 except that guide member 82 is further provided in the configuration of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG.

  Guide member 82 is a plate material having opening 83 and substantially parallel to upper surface 39 a of silicon carbide raw material 39. The guide member 82 is provided on the inner wall of the upper crucible 44. Guide member 82 is arranged at a position substantially equal to silicon carbide seed crystal 35 in the height direction. Opening 83 is provided at a position facing growth surface 35 a of silicon carbide seed crystal 35 and exposes growth surface 35 a of silicon carbide seed crystal 35. Guide member 82 is a member for guiding the source gas to growth surface 35 a of silicon carbide seed crystal 35.

A gap 84 between the guide member 83 and the silicon carbide seed crystal 35 for preventing the polycrystalline silicon carbide growing on the guide member 83 from contacting the silicon carbide seed crystal 35 and the silicon carbide single crystal 71. Is formed. The width _{W 1} of the gap 84, for example, can be set to 0.5 to 5 mm.

Thus, by providing the plate-shaped guide member 82 having the opening 83 exposing the growth surface 35 a of the silicon carbide seed crystal 35 on the inner wall of the upper crucible 44, the gap between the lid 32 and the guide member 82 is provided. It is possible to suppress the source gas from reaching this space.
This makes it difficult for polycrystalline silicon carbide to grow on the lower surface 32 b of the lid 32 and the outer peripheral side surface of the pedestal main body 48, so that the contact between the polycrystalline silicon carbide, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 is achieved. Can be suppressed.

  As a material of the guide member 83, a material that is stable at a high temperature and generates little impurity gas may be used. Specifically, as the material of the guide member 83, for example, graphite (graphite) coated with graphite (graphite), tantalum carbide (TaC), or the like can be used.

  By coating graphite (graphite) with tantalum carbide (TaC), the carbon contained in the graphite reacts with the source gas, so that carbon is taken into the growing silicon carbide single crystal 71, and the silicon carbide single crystal. It can suppress that the quality of the crystal | crystallization 71 falls.

Silicon carbide single crystal manufacturing apparatus 80 according to the first modification of the first embodiment having such a configuration obtains the same effects as silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. Can do. Specifically, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.
A method for manufacturing silicon carbide single crystal 71 using silicon carbide single crystal manufacturing apparatus 80 according to the first modification of the first embodiment is similar to that of silicon carbide single crystal 71 described in the first embodiment. The same method as the manufacturing method can be used, and the same effect as the method for manufacturing silicon carbide single crystal 71 of the first embodiment can be obtained.

  In silicon carbide single crystal manufacturing apparatus 80 according to the first modification of the first embodiment, volume of space 46 in crucible 31 can be changed by moving upper crucible 42 relative to lower crucible 41. The case where the crucible 31 is used has been described as an example. However, instead of the crucible 31, a crucible in which the volume in the crucible cannot be changed (a crucible 102 shown in FIG. 12 described later) may be used. Good.

FIG. 10 is a cross-sectional view of the main part of the silicon carbide single crystal manufacturing apparatus according to the second modification of the first embodiment of the present invention.
In FIG. 10, the vacuum vessel 11, the heat insulating member 12, the support member 15, the heating means 16, and the first radiation temperature, which are constituent elements of the silicon carbide single crystal manufacturing apparatus 85 according to the second modification of the first embodiment. Illustration of the total 18, the second radiation thermometer 19, and the upper crucible elevating means 38 (see FIGS. 1 and 2) is omitted. Further, in FIG. 10, the same components as those in the structure shown in FIG.

Referring to FIG. 10, silicon carbide single crystal manufacturing apparatus 85 according to a second modification of the first embodiment is a silicon carbide single crystal provided in silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. It is comprised similarly to the silicon carbide single crystal manufacturing apparatus 10 except having provided the silicon carbide single crystal manufacturing apparatus main body 86 instead of the crystal manufacturing apparatus main body 13. FIG.
Silicon carbide single crystal manufacturing apparatus 86 is configured similarly to silicon carbide single crystal manufacturing apparatus main body 13 except that guide member 87 is further provided in the configuration of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG.

The guide member 87 has a cylindrical portion 88 and a plate portion 89. The cylindrical part 88 is cylindrical. Cylindrical portion 88 is arranged below silicon carbide seed crystal 35 so that growth surface 35a of silicon carbide seed crystal 35 is exposed. Cylindrical portion 88 functions as a guide that guides the source gas to growth surface 35 a of silicon carbide seed crystal 35.
Thus, by providing the cylindrical portion 88 that exposes the growth surface 35 a of the silicon carbide seed crystal 35 below the silicon carbide seed crystal 35, the concentration distribution of the source gas follows the internal shape of the cylindrical portion 88. Since the distribution can be achieved, silicon carbide seed crystal 71 can be grown in a cylindrical shape corresponding to the internal shape of cylindrical portion 88.

  Between cylindrical portion 88 and silicon carbide seed crystal 35, polycrystalline silicon carbide growing on cylindrical portion 88 is prevented from contacting silicon carbide seed crystal 35 and silicon carbide single crystal 71. A gap 91 is formed. The width | variety of the clearance gap 91 can be 0.5-5 mm, for example.

  One end of the plate portion 89 is formed integrally with the cylindrical portion 88, and the other end is fixed to the inner wall of the upper crucible 42. Plate portion 89 is a plate material substantially parallel to upper surface 39 a of silicon carbide raw material 39. Plate portion 89 functions as a guide member that guides the source gas to growth surface 35 a of silicon carbide seed crystal 35 and also functions as a support member for supporting cylindrical portion 88.

Thus, by providing the plate portion 89 between the cylindrical portion 88 and the inner wall of the upper crucible 44, it is possible to suppress the source gas from reaching the space between the lid body 32 and the guide member 87. .
This makes it difficult for polycrystalline silicon carbide to grow on the lower surface 32 b of the lid 32 and the outer peripheral side surface of the pedestal main body 48, so that the contact between the polycrystalline silicon carbide, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 is achieved. Can be suppressed.

  As a material of the guide member 87, a material that is stable at a high temperature and generates little impurity gas may be used. Specifically, as the material of the guide member 87, for example, graphite (graphite) coated with graphite (graphite), tantalum carbide (TaC), or the like can be used.

By coating graphite (graphite) with tantalum carbide (TaC), the carbon contained in the graphite reacts with the source gas, so that carbon is taken into the growing silicon carbide single crystal 71, and the silicon carbide single crystal. It can suppress that the quality of the crystal | crystallization 71 falls.
When graphite is used as the material of the guide member 87, only the inner surface of the cylindrical portion 88 may be covered with tantalum carbide (TaC).

Silicon carbide single crystal manufacturing apparatus 85 according to the second modification of the first embodiment configured as described above can obtain the same effects as silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. . Specifically, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.
A method for manufacturing silicon carbide single crystal 71 using silicon carbide single crystal manufacturing apparatus 85 according to the second modification of the first embodiment is similar to that of silicon carbide single crystal 71 described in the first embodiment. The same method as the manufacturing method can be used, and the same effect as the method for manufacturing silicon carbide single crystal 71 of the first embodiment can be obtained.

  In the silicon carbide single crystal manufacturing apparatus 85 according to the second modification of the first embodiment, the volume of the space 46 in the crucible 31 can be changed by moving the upper crucible 42 with respect to the lower crucible 41. The case where the crucible 31 is used has been described as an example. However, instead of the crucible 31, a crucible in which the volume in the crucible cannot be changed (a crucible 102 shown in FIG. 12 described later) may be used. Good.

FIG. 11 is a cross sectional view of a main part of a silicon carbide single crystal manufacturing apparatus according to a third modification of the first embodiment of the present invention.
In FIG. 11, the vacuum container 11, the heat insulation member 12, the support member 15, the heating means 16, and the 1st radiation temperature which are the components of the silicon carbide single crystal manufacturing apparatus 90 which concerns on the 3rd modification of 1st Embodiment. Illustration of the total 18, the second radiation thermometer 19, and the upper crucible elevating means 38 (see FIGS. 1 and 2) is omitted. In FIG. 11, the same components as those of the structure shown in FIG.

Referring to FIG. 11, silicon carbide single crystal manufacturing apparatus 90 according to the third modification of the first embodiment is a silicon carbide single crystal provided in silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. It is comprised similarly to the silicon carbide single crystal manufacturing apparatus 10 except having provided the silicon carbide single crystal manufacturing apparatus main body 91 instead of the crystal manufacturing apparatus main body 13. FIG.
Silicon carbide single crystal manufacturing apparatus 91 is configured in the same manner as silicon carbide single crystal manufacturing apparatus main body 13 except that guide member 93 is further provided in the configuration of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG.

  Referring to FIG. 11, the guide member 93 is provided on the inner wall of the upper crucible 42. Guide member 93 has a cylindrical portion 94 that has a wider shape as it goes from growth surface 35 a of silicon carbide seed crystal 35 to upper surface 39 a of silicon carbide raw material 39. Cylindrical portion 94 has a truncated cone shape whose diameter increases from the growth surface 35 a of silicon carbide seed crystal 35 toward upper surface 39 a of silicon carbide raw material 39.

  Thus, by providing the cylindrical portion 94 having a truncated cone shape with a diameter increasing from the growth surface 35a of the silicon carbide seed crystal 35 toward the upper surface 39a of the silicon carbide raw material 39, the silicon carbide raw material 39 is sublimated. The produced raw material gas is guided to the growth surface 35a of the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 corresponding to the shape of the cylindrical portion 94 can be grown.

  As a material of the guide member 93, a material that is stable at a high temperature and generates little impurity gas may be used. Specifically, as the material of the guide member 93, for example, graphite (graphite) coated with graphite (graphite), tantalum carbide (TaC), or the like can be used.

By coating graphite (graphite) with tantalum carbide (TaC), the carbon contained in the graphite reacts with the source gas, so that carbon is taken into the growing silicon carbide single crystal 71, and the silicon carbide single crystal. It can suppress that the quality of the crystal | crystallization 71 falls.
Further, when graphite is used as the material of the guide member 93, only the inner surface of the guide member 93 constituting the cylindrical portion 94 may be covered with tantalum carbide (TaC).

Silicon carbide single crystal manufacturing apparatus 90 according to the third modification of the first embodiment having the above-described configuration can obtain the same effects as silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. . Specifically, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.
A method for manufacturing silicon carbide single crystal 71 using silicon carbide single crystal manufacturing apparatus 90 according to the third modification of the first embodiment is similar to that of silicon carbide single crystal 71 described in the first embodiment. The same method as the manufacturing method can be used, and the same effect as the method for manufacturing silicon carbide single crystal 71 of the first embodiment can be obtained.

FIG. 12 is a cross-sectional view of the main part of the silicon carbide single crystal manufacturing apparatus according to the fourth modification of the first embodiment of the present invention.
In FIG. 12, the vacuum container 11, the heat insulation member 12, the support member 15, the heating means 16, and the 1st radiation temperature which are the components of the silicon carbide single crystal manufacturing apparatus 100 which concerns on the 4th modification of 1st Embodiment. Illustration of the total 18, the second radiation thermometer 19, and the upper crucible elevating means 38 (see FIGS. 1 and 2) is omitted. In FIG. 12, the same components as those of the structure shown in FIG.

  Referring to FIG. 12, silicon carbide single crystal manufacturing apparatus 100 according to the fourth modification of the first embodiment is similar to silicon carbide single crystal manufacturing apparatus 90 according to the third modification of the first embodiment. Instead of the silicon carbide single crystal manufacturing apparatus main body 91 provided, a silicon carbide single crystal manufacturing apparatus main body 101 is provided in the same manner as the silicon carbide single crystal manufacturing apparatus 90.

  Silicon carbide single crystal manufacturing apparatus 101 is configured in the same manner as silicon carbide single crystal manufacturing apparatus main body 91 except that crucible 102 is provided instead of crucible 31 provided in silicon carbide single crystal manufacturing apparatus main body 91 shown in FIG. The The crucible 102 is configured such that the volume of the space 46 in the crucible 102 cannot be changed.

Silicon carbide single crystal manufacturing apparatus 100 according to the fourth modification of the first embodiment configured as described above can obtain the same effects as silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. . Specifically, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.
In addition, in the method for manufacturing silicon carbide single crystal 71 using silicon carbide single crystal manufacturing apparatus 100 according to the fourth modification of the first embodiment, space 46 in crucible 102 is grown during growth of silicon carbide single crystal 71. Except for not changing the volume, the same method as the method for manufacturing silicon carbide single crystal 71 described in the first embodiment can be used.

(Second Embodiment)
FIG. 13 is a cross-sectional view showing a schematic configuration of a silicon carbide single crystal manufacturing apparatus according to the second embodiment of the present invention.
In FIG. 13, the vacuum vessel 11, the heat insulating member 12, the support member 15, the heating means 16, the first radiation thermometer 18, and the second component that are components of the silicon carbide single crystal manufacturing apparatus 110 according to the second embodiment. The radiation thermometer 19 and the upper crucible elevating means 38 are not shown (see FIGS. 1 and 2).
Moreover, in FIG. 13, the same code | symbol is attached | subjected to the same component as the silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG.

  Referring to FIG. 13, silicon carbide single crystal manufacturing apparatus 110 of the second embodiment includes silicon carbide single crystal manufacturing apparatus main body 13 provided in silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. Instead, it is configured similarly to the silicon carbide single crystal manufacturing apparatus 10 except that the silicon carbide single crystal manufacturing apparatus main body 111 is provided.

  The silicon carbide single crystal manufacturing apparatus main body 111 is provided with a base 113 and a plate material lifting member 114 in place of the pedestal 33 and the plate material lifting member 36 provided in the silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG. Is configured similarly to the silicon carbide single crystal manufacturing apparatus main body 13.

The pedestal 113 includes a pedestal main body 116 and first to fourth plate members 51, 52-1, 52-2, and 52-3, which are a plurality of plate members. The pedestal main body 116 has a cylindrical shape and is provided on the lower surface 32b of the lid body 32 so as to expose the penetrating portion 32A. A silicon carbide seed crystal 35 is attached to the lower end surface 116 a of the pedestal main body 116 so as to close the open end located on the lower end side of the pedestal main body 116.
The pedestal main body 116 has an accommodating portion 118 that accommodates the first and second plate members 51 and 52-1. The accommodating portion 118 can accommodate the first and second plate members 51 and 52-1 by closing the open end located on the lower end side of the pedestal main body 116 with the silicon carbide seed crystal 35.

  The first to fourth plate members 51, 52-1, 52-2, and 52-3 are the first plate member 51, the second plate member 52-1, the third plate member 52-2, and the fourth plate member 52-. The third and fourth plate members 52-2 and 52-3 protrude from the upper surface 32a of the lid 32 in the order of three. In this state, first plate material 51 is in contact with silicon carbide seed crystal 35 (specifically, the surface of silicon carbide seed crystal 35 located on the opposite side of growth surface 35a).

The 2nd-4th board | plate materials 52-1, 52-2, 52-3 are set as the structure similar to the 2nd board | plate material 52 shown in FIG. 5 demonstrated previously. As for the 2nd-4th board | plate materials 52-1, 52-2, 52-3, the height of the hook accommodating part 56 of the 2nd board | plate material 52-1 is 3rd and 4th board | plate materials 52-2, 52-3. The height of the hook accommodating portion 56 of the fourth plate 52-3 is higher than the height of the hook accommodating portion 56 of the second and third plate members 52-1, 52-2. Is also configured to be low.
The thicknesses of the first to fourth plate members 51, 52-1, 52-2, and 52-3 can be set to 10 mm, for example. Moreover, silicon carbide, carbon, or the like can be used as the material of the pedestal 113 configured as described above.

  Referring to FIG. 13, the plate lifting member 114 includes a column portion 64, a first hook portion 65, a second hook portion 66-1, a third hook portion 66-2, and a fourth hook member. Hook part 66-3. The second to fourth hook portions 66-1, 66-2, 66-3 have the same configuration as the second hook portion 66 shown in FIGS. Yes.

The second hook portion 66-1 is disposed above the first hook portion 65 and is a hook for pulling up the second plate member 52-1. The third hook portion 66-2 is disposed above the second hook portion 66-1, and is a hook for lifting the third plate member 52-2.
The 4th hook part 66-3 is arrange | positioned above the 3rd hook part 66-2, and is a hook for pulling up the 4th board | plate material 52-3.
The plate lifting member 114 having the above-described configuration is pulled up upward, whereby the fourth plate member 52-3, the third plate member 52-2, the second plate member 52-1, and the first plate member 51 are arranged in this order. Remove the plate.

  According to the silicon carbide single crystal manufacturing apparatus of the second embodiment, the pedestal main body 116 including the accommodating portion 118 that accommodates the first and second plate members 51 and 52-1, and the accommodating portion 118 and the accommodating portion 118. A pedestal 113 made up of the first to fourth plate members 51, 52-1, 52-2, 52-3, a fourth plate member 52-3, a third plate member 52-2, and a second plate stacked on top of each other. By including the plate material 52-1 and the plate material lifting member 114 that pulls up the plate material in order of the first plate material 51, the thickness of the pedestal 113 is reduced, and the pedestal 113 and the silicon carbide species before the thickness is reduced The thickness of the first structure E made of the crystal 35 is made as equal as possible to the thickness of the second structure made of the pedestal 113, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 having a reduced thickness. It becomes possible.

  Accordingly, the heat dissipation characteristics of the first structure E that radiates heat from the upper surface of the pedestal 113 before the thickness is reduced, and the second structure that radiates heat from the upper surface of the pedestal 113 that is reduced in thickness. Therefore, the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial stage of growth and the crystal growth of the silicon carbide single crystal 71 when the growth of the silicon carbide single crystal 71 progresses. It is possible to reduce the difference between the temperature distribution on the surface.

  Therefore, silicon carbide single crystal 71 is formed under conditions close to optimum crystal growth conditions (specifically, conditions in which crystalline growth surface 71a is convex and crystal defects are unlikely to occur) at the initial growth stage of silicon carbide single crystal 71. Since it is possible to grow, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.

  A method for manufacturing silicon carbide single crystal 71 using silicon carbide single crystal manufacturing apparatus 110 of the second embodiment is the same as the method for manufacturing silicon carbide single crystal 71 described in the first embodiment. In addition, the same effects as those of the method for manufacturing silicon carbide single crystal 71 described in the first embodiment can be obtained.

A guide member 82 shown in FIG. 9, a guide member 87 shown in FIG. 10, and a guide member 93 shown in FIG. 11 are formed on the inner wall of the upper crucible 42 provided in the silicon carbide single crystal manufacturing apparatus 110 of the second embodiment. Any one of the guide members may be provided.
Moreover, you may provide the crucible 102 shown in FIG. 12 instead of the crucible 31 which comprises the silicon carbide single crystal manufacturing apparatus 110 of 2nd Embodiment.
Further, instead of the pedestal main body 116 constituting the silicon carbide single crystal manufacturing apparatus 110 of the second embodiment, a pedestal main body 48 shown in FIG. 2 is provided, and the silicon carbide seed crystal 35 is attached to the lower surface 48 b of the pedestal main body 48. May be.

  In the second embodiment, as an example, the case where the silicon carbide single crystal 71 is produced by the sublimation recrystallization method has been described. However, the present invention can be applied to, for example, silane or propane instead of the source gas (sublimation gas). The present invention can also be applied to a CVD (Chemical Vapor Deposition) method using, as a raw material.

(Third embodiment)
FIG. 14 is a cross-sectional view showing a schematic configuration of a silicon carbide single crystal manufacturing apparatus according to the third embodiment of the present invention.
In FIG. 14, the vacuum container 11, the heat insulation member 12, the support member 15, the heating means 16, the 1st radiation thermometer 18, and 2nd which are the components of the silicon carbide single crystal manufacturing apparatus 120 which concerns on 3rd Embodiment. The radiation thermometer 19 and the upper crucible elevating means 38 (see FIGS. 1 and 2) are not shown. In FIG. 14, the same components as those of silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG.

Referring to FIG. 14, silicon carbide single crystal manufacturing apparatus 120 of the third embodiment includes silicon carbide single crystal manufacturing apparatus main body 13 provided in silicon carbide single crystal manufacturing apparatus 10 of the first embodiment. Instead, it is configured in the same manner as the silicon carbide single crystal manufacturing apparatus 10 except that the silicon carbide single crystal manufacturing apparatus main body 121 is provided.
The silicon carbide single crystal manufacturing apparatus main body 121 is a silicon carbide single crystal manufacturing apparatus except that a pedestal 123 is provided instead of the pedestal 33 and the plate material lifting member 36 provided in the silicon carbide single crystal manufacturing apparatus main body 13 shown in FIG. The configuration is the same as that of the apparatus main body 13.

The pedestal 123 includes a pedestal main body 48 and a cutting pedestal member 125. The cutting base member 125 is a member having a cylindrical shape. The lower end of the cutting base member 125 is accommodated in the accommodating portion 54, and the lower surface 125 a is in contact with the upper surface 48 a of the pedestal main body 48. In addition, the cutting pedestal member 125 protrudes from the upper surface 32 a of the lid 32 in the state of being accommodated in the accommodating portion 54.
Cutting base member 125 is a member that is cut in accordance with the growth of silicon carbide single crystal 71, and has first and second cutting positions 126 and 127. The thickness of the cutting base member 125 can be set to 150 mm, for example.

  FIG. 15 is a cross-sectional view schematically showing a silicon carbide single crystal manufacturing apparatus provided with a pedestal cut at a first cutting position. 15, the same components as those of silicon carbide single crystal manufacturing apparatus 120 shown in FIG. FIG. 15 schematically shows silicon carbide single crystal 71 in a state of being grown more than silicon carbide single crystal 71 shown in FIG.

Referring to FIG. 14, the first cutting position 126 is a position to be cut first, and is provided at a distance D ₄ (for example, 20 mm) from the upper surface 125 b of the cutting base member 125.
Referring to FIGS. 14 and 15, when the thickness of the silicon carbide single crystal 71 during growth was nearly equal to the value of the distance D _4, and cutting the cutting carriage member 125 in a first cutting position 126, By removing the upper end portion of the cut base member 125 for cutting, the thickness of the base 123 is reduced.

Thus, the thickness M ₅ of the first structure F consisting of the base 123 and the silicon carbide seed crystal 35 before cutting shown in FIG. 14, the base 123 has been cut shown in Figure 15, a silicon carbide seed crystal 35 and, Since the thickness M _{6 of} the second structure G made of the silicon carbide single crystal 71 can be made as equal as possible, the upper portion of the pedestal 123 shown in FIG. 14 (in this case, the upper portion of the cutting pedestal member 125) ) And heat dissipation characteristics of the first structure F that dissipates heat, and heat dissipation of the second structure G that dissipates heat from the upper portion of the pedestal 123 (in this case, the upper portion of the cutting pedestal member 125) shown in FIG. The difference between the characteristics and the characteristics can be reduced.

  Therefore, the difference between the temperature distribution of crystal growth surface 71a of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 14 and the temperature distribution of crystal growth surface 71b of silicon carbide single crystal 71 shown in FIG. 15 can be reduced. It becomes possible.

  That is, the silicon carbide single crystal 71 is formed under conditions close to optimum crystal growth conditions at the initial stage of growth of the silicon carbide single crystal 71 (specifically, conditions where the crystal growth surface 71a is convex and crystal defects are not easily generated). It becomes possible to grow. Thereby, silicon carbide single crystal 71 with few crystal defects and high quality can be manufactured.

  FIG. 16 is a cross-sectional view schematically showing a silicon carbide single crystal manufacturing apparatus provided with a pedestal cut at the second cutting position. 16, the same components as those of silicon carbide single crystal manufacturing apparatus 120 provided in FIG. 14 are denoted by the same reference numerals. 16 schematically shows silicon carbide single crystal 71 in a further grown state than silicon carbide single crystal 71 shown in FIG.

Referring to FIG. 14, the second cutting position 126 is a position to be cut next to the first cutting position 125, and is a position at a distance D ₅ (for example, 40 mm) from the upper surface 125 b of the cutting base member 125. Is provided.
Referring to FIGS. 14 and 16, when the thickness of the silicon carbide single crystal 71 becomes substantially equal to the value of the distance D _5, cutting the cutting carriage member 125 in the second cutting position 127, was cut By removing the upper end portion of the cutting base member 125, the thickness of the base 123 is further reduced from the state shown in FIG.

Thus, the thickness M ₅ of the first structure F consisting front of the pedestal 123 and the silicon carbide seed crystal 35 to be cut shown in Figure 14, the base 123 has been cut shown in FIG. 16, a silicon carbide seed crystal 35 , And the thickness M _{7 of} the second structure H made of the silicon carbide single crystal 71 can be made as equal as possible, so that the first structure that radiates heat from the upper portion of the pedestal 123 shown in FIG. The difference between the heat dissipation characteristics of the body F and the heat dissipation characteristics of the second structure H that dissipates heat from the upper portion of the pedestal 123 shown in FIG. 15 (in this case, the upper portion of the cutting pedestal member 125) can be reduced. It becomes possible.

  Therefore, the difference between the temperature distribution of crystal growth surface 71a of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 14 and the temperature distribution of crystal growth surface 71c of silicon carbide single crystal 71 shown in FIG. 16 can be reduced. It becomes possible.

  That is, the crystal growth surface 71c is a convex surface under conditions close to the optimum crystal growth conditions (specifically, the crystal growth surface 71a is a convex surface and a crystal defect is less likely to occur) at the initial growth stage of the silicon carbide single crystal 71. It becomes possible to grow the formed silicon carbide single crystal 71. Thereby, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.

  As a material for the pedestal 123 having the above structure, silicon carbide, carbon, or the like may be used. As a result, the difference in thermal expansion coefficient between silicon carbide seed crystal 35 and silicon carbide single crystal 71 is reduced, so that growing silicon carbide single crystal 71 is damaged due to the difference in thermal expansion coefficient. Can be suppressed.

  In the third embodiment, the cutting base member 125 is taken as an example, and a case where two cutting positions (first and second cutting positions 126 and 127) are provided is described as an example. A cutting base member 125 having two or more cutting positions may be used.

Further, a guide member 82 shown in FIG. 9, a guide member 87 shown in FIG. 10, and a guide member 93 shown in FIG. 11 are formed on the inner wall of the upper crucible 42 provided in the silicon carbide single crystal manufacturing apparatus 120 of the third embodiment. Any one of the guide members may be provided.
Furthermore, instead of the crucible 31 provided in the silicon carbide single crystal manufacturing apparatus 120 of the third embodiment, a crucible 102 shown in FIG. 12 may be provided.

Next, with reference to FIGS. 14-16, the manufacturing method of the silicon carbide single crystal 71 of 3rd Embodiment is demonstrated.
First, as shown in FIG. 14, a silicon carbide raw material 39 is introduced into the lower crucible 41. Next, the silicon carbide seed crystal 35 is attached to the lower surface 48 b of the pedestal main body 48. Next, the lid 32 is disposed on the upper end of the upper crucible 42 so that the growth surface 35 a of the silicon carbide seed crystal 35 and the upper surface 39 a of the silicon carbide raw material 39 in the crucible 31 face each other.

  Next, the cutting pedestal member 125 is disposed in the accommodating portion 54 of the pedestal main body 48, and a part of the cutting pedestal member 125 (specifically, the first and second cutting positions 126 and 127) is covered with the lid. It protrudes from the upper surface 32a of 32. At this stage, as shown in FIG. 14, the volume of the space 46 in the crucible 31 is minimized.

  Next, by heating the silicon carbide source material 39 in the crucible 31, the source gas is sublimated on the growth surface 35a of the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 is initially grown on the growth surface 35a. At this time, the optimum crystal growth conditions acquired in advance (specifically, conditions under which the crystal growth surface 71a is a convex surface and crystal defects are not easily generated) are used.

Then, at the stage where the thickness of the distance D ₄ and the silicon carbide single crystal 71 shown in FIG. 15 shown in FIG. 14 becomes substantially equal, as shown in FIG. 15, the cutting carriage member 125 shown in FIG. 14 first By cutting at the cutting position 126 and removing the upper end of the cut base member 125 for cutting, the thickness of the base 123 is reduced.

  Thereby, the heat dissipation characteristic of the first structure F that releases heat from the upper part of the pedestal 123 shown in FIG. 14 and the heat dissipation characteristic of the second structure G that dissipates heat from the upper part of the pedestal 123 shown in FIG. Therefore, the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial stage of growth and the temperature of the crystal growth surface 71b of the silicon carbide single crystal 71 when the growth of the silicon carbide single crystal 71 progresses. The difference between the distribution and the distribution can be reduced.

  As a result, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The formed silicon carbide single crystal 71 can be grown.

In the case of forming a silicon carbide single crystal 71 shown in FIG. 15, as the distance D ₂ shown in FIG. 15 becomes substantially equal to the distance D ₁ shown in FIG. 14, the upper crucible in accordance with the growth of silicon carbide single crystal 71 42 is moved upward.
This makes it possible to bring the growth conditions of silicon carbide single crystal 71 shown in FIG. 15 closer to the growth conditions of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. Silicon carbide single crystal 71 having excellent characteristics can be formed.

Then, at the stage where the thickness of the distance D ₅ and the silicon carbide single crystal 71 shown in FIG. 16 shown in FIG. 14 becomes substantially equal, as shown in FIG. 16, cutting with a second cutting position 127 shown in FIG. 14 By cutting the base member 125 and removing the upper end portion of the cut base member 125 for cutting, the thickness of the base 123 is made thinner than the state shown in FIG.

  Thereby, the heat dissipation characteristics of the first structure F that releases heat from the upper portion of the pedestal 123 shown in FIG. 14 and the heat from the upper portion of the pedestal 123 shown in FIG. 16 (in this case, the upper portion of the cutting pedestal member 125). Since the difference between the heat dissipation characteristics of the second structure H that dissipates heat is small, the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial stage of growth and the crystal of the silicon carbide single crystal 71 with further growth. The difference from the temperature distribution on the growth surface 71c can be reduced.

  Therefore, silicon carbide single crystal 71 can be grown under conditions close to the optimum crystal growth conditions at the initial stage of growth of silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The silicon carbide single crystal 71 can be grown.

Further, when forming silicon carbide single crystal 71 shown in FIG. 16, the upper crucible is adjusted in accordance with the growth of silicon carbide single crystal 71 so that distance D ₃ shown in FIG. 16 is substantially equal to distance D ₁ shown in FIG. 42 is moved upward.
Accordingly, the growth conditions of silicon carbide single crystal 71 shown in FIG. 16 can be made closer to the growth conditions of silicon carbide single crystal 71 in the initial stage of growth shown in FIG. Silicon carbide single crystal 71 having excellent characteristics can be formed.

  According to the method for manufacturing a silicon carbide single crystal of the third embodiment, the source gas obtained by sublimating silicon carbide source material 39 by heating is supplied to growth surface 35a of silicon carbide seed crystal 35 attached to base body 48. Then, the silicon carbide single crystal 71 is grown, and during the growth of the silicon carbide single crystal 71, the cutting base member 125 is cut in accordance with the growth of the silicon carbide single crystal 71 to reduce the thickness of the base 123. This makes it possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The silicon carbide single crystal 71 can be manufactured.

In the method for manufacturing silicon carbide single crystal 71 of the third embodiment, the case where the thickness of pedestal 33 is reduced during crystal growth has been described as an example. May be stopped, the cutting pedestal member 125 may be cut to reduce the thickness of the pedestal 123, and then the silicon carbide single crystal 71 may be grown.
When manufacturing silicon carbide single crystal 71 by such a method, the same effect as the method for manufacturing silicon carbide single crystal 71 of the third embodiment can be obtained.

  In the third embodiment, as an example, the case where the silicon carbide single crystal 71 is manufactured by the sublimation recrystallization method has been described. However, the present invention is not limited to the source gas (sublimation gas), for example, silane or propane. The present invention can also be applied to a CVD (Chemical Vapor Deposition) method using, as a raw material.

(Fourth embodiment)
17 to 24 are cross-sectional views showing steps of manufacturing the silicon carbide single crystal according to the fourth embodiment of the present invention. 17-24, the same code | symbol is attached | subjected to the same structure part as the structure shown in FIG.13 and FIG.14.
Although not shown, crucibles 31-1, 31-2, 31-3, and 31-4 shown in FIGS. 17 to 24 are supported by shaft portion 75 shown in FIG. 2 described above.

With reference to FIGS. 17-24, the manufacturing method of the silicon carbide single crystal 71 which concerns on 3rd Embodiment is demonstrated.
First, in the step shown in FIG. 17, a silicon carbide seed crystal is formed in the through-hole 32 </ b> A- 1 of the lid 32 a-1 disposed at the upper end of the crucible 31-1 including the lower crucible 41-1 and the upper crucible 42-1. A pedestal 141 to which 35 is attached is attached.
The pedestal 141 includes a pedestal main body 116 that includes the accommodating portion 118, and a cutting pedestal member 142. The pedestal main body 116 protrudes below the lower surface 32b-1 of the lid body 32-1. The pedestal member 142 for cutting is accommodated in the accommodating part 118, and protrudes upward from the upper surface 32a-1 of the lid body 32-1.

FIG. 17 schematically shows a state in which silicon carbide single crystal 71 at the initial growth stage is grown on growth surface 35 a of silicon carbide seed crystal 35.
Also, the crucible 31-1 and the lid 32-1 shown in FIG. 17 have the same configuration as the crucible 31 and the lid 32 shown in FIG.
Furthermore, at this stage, the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 to the top surface 39a-1 of the silicon carbide raw material 39-1 is configured such that the distance D _1.

Next, in a step shown in FIG. 18, silicon carbide single crystal 71 is grown from the state shown in FIG. At this stage, for example, the thickness of the silicon carbide single crystal 71 formed on the growth surface 35a of the silicon carbide seed crystal 35 can be set to, for example, 20 mm. At this stage, the growth of silicon carbide single crystal 71, the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 to the top surface 39a-1 of the silicon carbide raw material 39-1 is smaller than the distance _{D 1.}
The first cutting position 144 shown in FIG. 18 is a position to be cut first, and can be set, for example, at a position 20 mm thick from the upper surface 142a of the cutting base member 142 shown in FIG.

  Next, in the step shown in FIG. 19, the growth of the silicon carbide single crystal 71 is stopped once. Thereafter, the lower crucible 41-1 and the upper crucible 42-1 shown in FIG. 18 are removed from the shaft portion 75 not shown, and the silicon carbide single crystal 71 and the silicon carbide seed crystal are removed from the lid 32-1 shown in FIG. 35 is removed, and the lid 32-1 is removed from the upper crucible 42-1 shown in FIG.

  Next, a crucible 31-2 (a new crucible different from the crucible 31-1 shown in FIG. 18) formed by the lower crucible 41-2 and the upper crucible 42-2 shown in FIG. Then, a lid 32-2 (a new lid different from the lid 32-1 shown in FIG. 18) is assembled, and a silicon carbide raw material 39-2 is newly accommodated in the lower crucible 41-2.

Next, cutting base member 142 shown in FIG. 18 is cut at first cutting position 144, and from crystal growth surface 71a of silicon carbide single crystal 71 shown in FIG. 19 to upper surface 39a-2 of silicon carbide raw material 39-2. next distance _{D 1} which distance is shown in FIG. 17, and so that the upper end face of the pedestal body 116 is the upper surface 32a-2 and substantially flush lid 32-2 when mounted pedestal 141 to the lid 32-2 In addition, the base 141 (the base shown in FIG. 19) obtained by cutting the upper end of the base main body 116 is attached to the penetrating portion 32A-2 of the lid 32-2.

  As a result, the heat dissipation characteristics of the first structure I (the structure made of the base 141 and the silicon carbide seed crystal 35 shown in FIG. 17) that releases heat from the upper surface 141a of the base 141 shown in FIG. 17 are shown in FIG. The difference between the second structure J that radiates heat from the upper surface 141b of the pedestal 141 (the structure composed of the pedestal 141, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 shown in FIG. 19) is small. Therefore, it is possible to reduce the difference between the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial stage of growth and the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 that has further grown. Become.

  As a result, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The formed silicon carbide single crystal 71 can be grown.

Further, by setting such that the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 shown in FIG. 19 to the top surface 39a-2 of the silicon carbide raw material 39-2 is a distance _{D 1} shown in FIG. 17, FIG. 19 The growth conditions of the silicon carbide single crystal 71 shown in FIG. 17 can be made closer to the growth conditions of the silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 17, so that the characteristics are substantially uniform in the thickness direction. Silicon carbide single crystal 71 can be formed.

Next, in the process shown in FIG. 20, the growth of silicon carbide single crystal 71 is resumed from the state shown in FIG. In the step shown in FIG. 20, for example, a 20 mm silicon carbide single crystal 71 is further grown.
The second cutting position 146 shown in FIG. 20 is the second cutting position, and can be set, for example, at a position 20 mm thick from the upper surface 142b of the cutting base member 142 shown in FIG.

  Next, in the step shown in FIG. 21, the growth of the silicon carbide single crystal 71 is stopped once. Thereafter, the lower crucible 41-2 and the upper crucible 42-2 shown in FIG. 20 are removed from the shaft portion 75 (not shown), and the silicon carbide single crystal 71 and the silicon carbide seed crystal are removed from the lid 32-2 shown in FIG. 35 is removed, and the lid 32-2 is further removed from the upper crucible 42-2 shown in FIG.

  Next, a crucible 31-3 (a new crucible different from the crucible 31-2 shown in FIG. 20) constituted by the lower crucible 41-3 and the upper crucible 42-3 shown in FIG. And the lid 32-3 (a new lid different from the lid 32-2 shown in FIG. 20) is assembled, and the silicon carbide raw material 39-3 is newly accommodated in the lower crucible 41-3.

Next, the cutting base member 142 shown in FIG. 18 is cut at the second cutting position 146, and
Mounting next distance _{D 1} the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 shown in FIG. 21 to the top surface 39a-3 of the silicon carbide raw material 39-3 is shown in Figure 18, and the pedestal 141 to the lid 32-3 The pedestal 141 (pedestal shown in FIG. 21) cut from the upper end of the pedestal main body 116 so that the upper end surface of the pedestal main body 116 is substantially flush with the upper surface 32a-3 of the lid 32-3. -3 through part 32A-3.

  Accordingly, the heat dissipation characteristics of the first structure I that releases heat from the upper surface 141a of the pedestal 141 shown in FIG. 17 and the second structure K that radiates heat from the upper surface 141c of the pedestal 141 shown in FIG. Since the difference between the heat radiation characteristics of the base 141, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 shown in FIG. 21 is small, the temperature of the crystal growth surface 71a of the silicon carbide single crystal 71 in the initial growth stage It is possible to reduce the difference between the distribution and the temperature distribution of crystal growth surface 71a of silicon carbide single crystal 71 that has further grown.

  As a result, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The formed silicon carbide single crystal 71 can be grown.

Further, by setting such that the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 shown in FIG. 21 to the top surface 39a-2 of the silicon carbide raw material 39-2 is a distance _{D 1} shown in FIG. 17, FIG. 21 The growth conditions of the silicon carbide single crystal 71 shown in FIG. 17 can be made closer to the growth conditions of the silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 17, so that the characteristics are substantially uniform in the thickness direction. Silicon carbide single crystal 71 can be formed.

Next, in the step shown in FIG. 22, the growth of silicon carbide single crystal 71 is resumed from the state shown in FIG. In the step shown in FIG. 22, for example, a 20 mm silicon carbide single crystal 71 is further grown.
The third cutting position 147 shown in FIG. 22 is the third cutting position, and can be set, for example, at a position 20 mm thick from the upper surface 142c of the cutting base member 142 shown in FIG.

  Next, in the step shown in FIG. 23, the growth of the silicon carbide single crystal 71 is stopped once. Thereafter, the lower crucible 41-3 and the upper crucible 42-3 shown in FIG. 22 are removed from the shaft 75 (not shown), and the silicon carbide single crystal 71 and the silicon carbide seed crystal are removed from the lid 32-3 shown in FIG. The base 141 integrated with 35 is removed, and the lid 32-3 is further removed from the upper crucible 42-3 shown in FIG.

  Next, a crucible 31-4 (a new crucible different from the crucible 31-3 shown in FIG. 22) composed of a lower crucible 41-4 and an upper crucible 42-4 shown in FIG. And the lid body 32-4 (a new lid body different from the lid body 32-3 shown in FIG. 22) is assembled, and the silicon carbide raw material 39-4 is newly accommodated in the lower crucible 41-4.

Next, cutting base member 142 shown in FIG. 22 is cut at third cutting position 147, and from crystal growth surface 71a of silicon carbide single crystal 71 to upper surface 39a-4 of silicon carbide raw material 39-4 shown in FIG. so that the distance becomes a distance D ₁ shown in FIG. 17, the outer periphery and the outer periphery of the silicon carbide single crystal 71 of the base body 116, a support member 149 provided to support the pedestal body 116 and the silicon carbide single crystal 71, the support member 149, the second structure L (a structure made up of the pedestal 141, the silicon carbide seed crystal 35, and the silicon carbide single crystal 71 shown in FIG. 23) is inserted into the through-hole 32A-4 of the lid 32-4. Install.
At this stage, a part of the upper end of the silicon carbide single crystal 71 protrudes from the upper surface 32a-4 of the lid body 32-4.

  Thereby, the heat dissipation characteristics of the first structure I that releases heat from the upper surface 141a of the pedestal 141 shown in FIG. 17 and the heat dissipation of the second structure L that radiates heat from the upper surface 141d of the pedestal 141 shown in FIG. Therefore, the difference between the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 at the initial stage of growth and the temperature distribution of the crystal growth surface 71a of the silicon carbide single crystal 71 that has further grown is small. Can be reduced.

  As a result, it becomes possible to grow the silicon carbide single crystal 71 under conditions close to the optimum crystal growth conditions at the initial stage of the growth of the silicon carbide single crystal 71, so that there are few crystal defects, high quality, and a long length. The formed silicon carbide single crystal 71 can be grown.

Further, by setting such that the distance from the crystal growth surface 71a of the silicon carbide single crystal 71 shown in FIG. 23 to the upper surface 39a-4 of the silicon carbide raw material 39-4 is a distance _{D 1} shown in FIG. 17, FIG. 23 The growth conditions of the silicon carbide single crystal 71 shown in FIG. 17 can be made closer to the growth conditions of the silicon carbide single crystal 71 in the initial stage of growth shown in FIG. 17, so that the characteristics are substantially uniform in the thickness direction. Silicon carbide single crystal 71 can be formed.

Next, in the step shown in FIG. 24, the growth of silicon carbide single crystal 71 is resumed from the state shown in FIG. In the step shown in FIG. 24, for example, a 20 mm silicon carbide single crystal 71 is further grown.
Note that after the process shown in FIG. 24, the same process as the process shown in FIG. 23 described above is performed, and then silicon carbide single crystal 71 may be further grown.

  According to the silicon carbide single crystal manufacturing method of the fourth embodiment, the growth of silicon carbide single crystal 71 is once stopped, and cutting base member 142 is cut in accordance with the growth of silicon carbide single crystal 71. While reducing the thickness of pedestal 141, the crucible, the lid, and the silicon carbide raw material are replaced with new ones, and silicon carbide raw material 39a is heated on the growth surface 35a of silicon carbide seed crystal 35 attached to pedestal 141 by heating. -1, 39a-2, 39a-3, 39a-4 are supplied with the source gas sublimated to grow the silicon carbide single crystal 71, so that the optimum crystal growth conditions at the initial growth stage of the silicon carbide single crystal 71 are obtained. Since silicon carbide single crystal 71 can be grown under close conditions, silicon carbide single crystal 71 having few crystal defects, high quality, and long length can be manufactured.

  In the fourth embodiment, as an example, the case where the silicon carbide single crystal 71 is manufactured by the sublimation recrystallization method has been described. However, the present invention can be applied to, for example, silane or propane instead of the source gas (sublimation gas). The present invention can also be applied to a CVD (Chemical Vapor Deposition) method using, as a raw material.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and within the scope of the present invention described in the claims, Various modifications and changes are possible.

  A silicon carbide single crystal manufacturing apparatus and a silicon carbide single crystal manufacturing method according to the present invention include a silicon carbide single crystal manufacturing apparatus and a silicon carbide single crystal that are capable of manufacturing a high-quality and long silicon carbide single crystal. It can be used for the manufacturing method.

DESCRIPTION OF SYMBOLS 10,80,85,90,100,110,120 ... Silicon carbide single crystal manufacturing apparatus, 11 ... Vacuum vessel, 12 ... Thermal insulation member, 13, 81, 86, 91, 101, 111, 121 ... Silicon carbide single crystal manufacture Device main body, 15 ... support member, 15A ... through hole, 16 ... heating means, 18 ... first radiation thermometer, 19 ... second radiation thermometer, 22 ... gas introduction hole, 23 ... gas discharge hole, 25 ... Device main body accommodating portion, 26, 32A ... penetrating portion, 27 ... window hole, 31, 31-1, 31-2, 31-3, 31-4, 102 ... crucible, 32, 32-1, 32-2, 32 -3, 32-4 ... lid body, 32a, 32a-2, 32a-2, 32a-3, 32a-4, 39a, 39a-1, 39a-2, 39a-3, 39a-4, 48a, 51a, 52a, 125b, 125c, 125d, 141a, 141b, 1 41c, 141d, 142a, 142b, 142c ... upper surface, 32A, 32A-1, 32A-2, 32A-3, 32A-4 ... penetrating part, 32b, 32b-1, 32b-2, 32b-3, 32b-4 , 48b, 125a ... lower surface, 33, 113, 123, 141 ... pedestal, 35 ... silicon carbide seed crystal, 35a ... growth surface, 36, 114 ... plate material lifting member, 38 ... upper crucible lifting / lowering means, 39, 39-1, 39-2, 39-3, 39-4 ... silicon carbide raw material, 41, 41-1, 41-2, 41-3, 41-4 ... lower crucible, 41a, 75a ... outer peripheral side, 42, 42-1, 42-2, 42-3, 42-4 ... upper crucible, 43, 44 ... slide part, 43a, 44a ... slide surface, 46 ... space, 48, 116 ... pedestal body, 51 ... first plate member, 52, 52 -1 ... 2nd plate, 52-2 ... 1st Plate material, 52-3 ... fourth plate material, 54, 118 ... housing portion, 56 ... hook housing portion, 56a ... ceiling surface, 57, 61 ... strut portion passage portion, 58, 62 ... hook passage portion, 64 ... strut , 65 ... first hook part, 66 ... second hook part, 71 ... silicon carbide single crystal, 71a, 71b, 71c ... crystal growth surface, 75 ... shaft part, 76 ... shaft guide part, 77 ... drive part , 82, 87, 93: guide member, 83: opening, 84: gap, 88, 94 ... cylindrical portion, 89 ... plate portion, 116a ... lower end surface, 125, 142 ... cutting base member, 126, 144 ... 1st cutting position, 127, 146 ... 2nd cutting position, 147 ... 3rd cutting position, 149 ... support members A, E, F, I ... 1st structure, B, C, G, H, J, K: second structure, D ₁ , D ₂ , D ₃ , D ₄ , D ₅ ... distance, J ₁ ... length, M ₁ , M ₂ , M ₃ , M ₄ , M ₅ , M ₆ , M ₇ ... thickness, W ₁ ... width

Claims (25)

A silicon carbide single crystal manufacturing apparatus for supplying a raw material gas to a growth surface of a silicon carbide seed crystal attached to a pedestal in a crucible and growing the silicon carbide single crystal on the silicon carbide seed crystal,
The said base is a structure which can make thickness of this base thin, The silicon carbide single crystal manufacturing apparatus characterized by the above-mentioned. The pedestal is disposed at the upper end of the crucible,
2. The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein the silicon carbide single crystal is grown by supplying a source gas obtained by sublimating the silicon carbide raw material to a growth surface of the silicon carbide seed crystal. .   3. The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein the pedestal includes a pedestal main body to which the silicon carbide seed crystal is attached, and a plurality of plate members stacked on the pedestal main body.   The pedestal main body is provided on a lid disposed at an upper end of the crucible, and the pedestal main body projects from a lower surface of the lid toward the upper surface of the silicon carbide raw material, and at least one The silicon carbide single crystal manufacturing apparatus according to claim 3, further comprising a housing portion that houses the plate material.   The silicon carbide single crystal manufacturing apparatus according to claim 4, wherein the housing portion houses the plurality of plate members so as not to protrude from an upper surface of the lid.   The silicon carbide single crystal manufacturing apparatus according to claim 4, wherein the housing portion and the plurality of plate members are stacked on the housing portion so as to protrude from the upper surface of the lid.   The silicon carbide single crystal manufacturing apparatus according to any one of claims 3 to 6, wherein the base body is integrated with the lid.   8. The silicon carbide single crystal manufacturing apparatus according to claim 1, wherein a guide member for guiding the source gas is provided on the crucible side on the silicon carbide seed crystal side.   9. The carbonization according to claim 8, wherein the guide member is a plate material substantially parallel to an upper surface of the silicon carbide raw material, and has an opening that exposes a growth surface of the silicon carbide seed crystal. Silicon single crystal manufacturing equipment.   9. The silicon carbide single crystal manufacturing apparatus according to claim 8, wherein the guide member has a cylindrical portion that exposes a growth surface of the silicon carbide seed crystal at a position below the silicon carbide seed crystal.   11. The silicon carbide single crystal manufacturing apparatus according to claim 10, wherein the cylindrical portion has the same width in a direction from a growth surface of the silicon carbide seed crystal toward an upper surface of the silicon carbide raw material.   11. The silicon carbide single crystal manufacturing apparatus according to claim 10, wherein the cylindrical portion has a wider shape from a growth surface of the silicon carbide seed crystal toward an upper surface of the silicon carbide raw material. The crucible has an upper crucible in which the lid body is disposed, and a lower crucible containing the silicon carbide raw material,
The silicon carbide single crystal manufacturing apparatus according to any one of claims 1 to 12, wherein the upper crucible and the lower crucible are configured to be relatively movable with respect to a vertical direction.   The silicon carbide single crystal manufacturing apparatus according to claim 13, wherein the guide member is provided on an inner wall of the upper crucible.   The silicon carbide single crystal manufacturing apparatus according to any one of claims 1 to 14, wherein a material of the pedestal is silicon carbide.   The silicon carbide single crystal manufacturing apparatus according to any one of claims 1 to 14, wherein a material of the pedestal is carbon.   A method for producing a silicon carbide single crystal in which a raw material gas is supplied to a growth surface of a silicon carbide seed crystal attached to a pedestal in a crucible to grow a silicon carbide single crystal on the silicon carbide seed crystal, A method for producing a silicon carbide single crystal, comprising reducing the thickness of the pedestal as the silicon single crystal grows.   The pedestal is disposed at the upper end of the crucible so that the silicon carbide seed crystal faces the silicon carbide raw material contained in the crucible, and the silicon carbide raw material is sublimated on the growth surface of the silicon carbide seed crystal. The method of manufacturing a silicon carbide single crystal according to claim 17, wherein the silicon carbide single crystal is grown by supplying a raw material gas.   The method for producing a silicon carbide single crystal according to claim 17 or 18, wherein the thickness of the pedestal is reduced during the growth of the silicon carbide single crystal.   The silicon carbide single crystal according to claim 17 or 18, wherein after the growth of the silicon carbide single crystal is stopped, the thickness of the pedestal is reduced, and then the silicon carbide single crystal is further grown. Production method. The pedestal has a pedestal body to which the silicon carbide seed crystal is attached, and a plurality of plate members stacked on the pedestal body.
The method for producing a silicon carbide single crystal according to any one of claims 18 to 20, wherein the thickness of the pedestal is reduced by removing the plate material. The pedestal main body is provided on a lid disposed at an upper end of the crucible, has a housing portion that projects from a bottom surface of the lid body toward a top surface of the silicon carbide raw material and that houses the plate material. ,
The method for producing a silicon carbide single crystal according to claim 21, wherein the silicon carbide single crystal is grown after the plurality of plate members are accommodated in the accommodating portion so as not to protrude from the upper surface of the lid. The pedestal main body is provided on a lid disposed at an upper end of the crucible, has a housing portion that projects from a bottom surface of the lid body toward a top surface of the silicon carbide raw material and that houses the plate material. ,
The silicon carbide single crystal is grown on the silicon carbide seed crystal after the housing portion and the plurality of plate members are stacked on the housing portion so as to protrude from the upper surface of the lid. 22. A method for producing a silicon carbide single crystal according to 21.   The pedestal is provided on a lid disposed at an upper end of the crucible, the pedestal is disposed so as to protrude from an upper surface of the lid, and the pedestal protrudes from an upper surface of the lid. The method for producing a silicon carbide single crystal according to any one of claims 18 to 20, wherein the thickness of the pedestal is reduced by cutting a part thereof.   25. The method according to claim 18, wherein when the silicon carbide seed crystal is grown, the distance between the upper surface of the silicon carbide raw material and the crystal growth surface of the silicon carbide single crystal is adjusted to be substantially equal. The manufacturing method of the silicon carbide single crystal of any one of Claims 1.

Images