JP2005126249A - Method for growing single crystal silicon carbide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide high-quality, high-performance single crystal SiC which has a wide terrace and high smoothness and forms few micropipe defect, interface defect, etc., by controlling the film thickness of the single crystal SiC at growth. <P>SOLUTION: In a method for growing the single crystal silicon carbide, a C atom-supplying substrate 17 for supplying carbon atoms is stacked on a single crystal SiC substrate 5 which serves as a seed crystal, an ultra-thin metallic Si melt layer 18 is interposed between the single crystal SiC substrate 5 and the C atom-supplying substrate 17, and heat-treatment is performed at a prescribed temperature of about ≥1,400°C for a prescribed time to grow the single crystal SiC on the single crystal SiC substrate 5 which serves as the seed crystal through liquid phase epitaxial growth. As the C atom-supplying substrate 17, at least one substrate chosen from the group consisting of a carbon substrate, a porous SiC substrate, a sintered SiC substrate and an amorphous SiC substrate is used. A spacer 19 with a thickness of about ≤50 μm is installed between the single crystal SiC substrate 5 and the C atom-supplying substrate 17 to control the thickness of the single crystal SiC grown between the single crystal SiC substrate 5 and the C atom-supplying substrate 17. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a single crystal silicon carbide that is capable of providing a high-quality, high-performance single crystal silicon carbide that has a wide terrace and high surface flatness while generating less micropipe defects and interface defects. It relates to the growth method.

  Silicon carbide (hereinafter referred to as SiC) is excellent in heat resistance and mechanical strength. Furthermore, it is resistant to radiation, and valence electron control of electrons and holes is easy by adding impurities. In addition, it has a wide forbidden bandwidth. Incidentally, it is about 3.0 eV for 6H type single crystal SiC and 3.3 eV for 4H type single crystal SiC. Therefore, it is possible to realize high temperature, high frequency, withstand voltage / environment resistance that cannot be realized with existing semiconductor materials such as Si (hereinafter referred to as Si) and gallium arsenide (hereinafter referred to as GaAs). . Therefore, it attracts attention and is expected as a semiconductor material for next-generation power devices and high-frequency devices. Further, hexagonal SiC has a lattice constant close to that of gallium nitride (hereinafter referred to as GaN), and is expected as a GaN substrate.

There are the following methods for producing this type of single crystal SiC.
For example, according to the sublimation recrystallization method (modified Rayleigh method), a single crystal SiC substrate is fixedly arranged as a seed crystal on the low temperature side in the crucible. A powder containing Si as a raw material is placed on the high temperature side. Heat the crucible to a high temperature between 1450 and 2400 ° C in an inert atmosphere. Thereby, the powder containing Si is sublimated and SiC is recrystallized on the surface of the seed crystal on the low temperature side. In this way, single crystal SiC is grown.

For example, according to Patent Document 1, a single crystal SiC substrate and a plate material composed of Si atoms and C atoms face each other in parallel with a small gap therebetween. In that state, a temperature gradient is provided so that the single crystal SiC substrate side is at a lower temperature than the plate material in an inert gas atmosphere at atmospheric pressure or lower and a SiC saturated vapor atmosphere. Then, by performing heat treatment, Si atoms and C atoms are sublimated and recrystallized in the minute gaps. In this way, a single crystal is deposited on the single crystal SiC substrate.
Furthermore, for example, according to Patent Document 2, a first epitaxial layer is formed on single-crystal SiC by a liquid phase epitaxial growth method (hereinafter referred to as LPE method). Thereafter, a second epitaxial layer is formed on the surface by a CVD method to remove micropipe defects.

JP-A-11-315000 Japanese National Patent Publication No. 10-509943

However, among the methods for forming single-crystal SiC, for example, in the case of the sublimation recrystallization method described in Patent Document 1, etc., the growth rate is very fast as several hundred μm / hr. It is decomposed and vaporized into Si, SiC ₂ and Si ₂ C and further reacts with a part of the crucible. For this reason, the types of gases that reach the surface of the seed crystal differ depending on the temperature change, and it is technically very difficult to control these partial pressures stoichiometrically accurately. Impurities are also likely to be mixed in, and crystal defects and micropipe defects are likely to occur due to the influence of the mixed impurities and strain caused by heat. In addition, performance such as generation of crystal grain boundaries due to many nucleation There is a problem that single crystal SiC stable in quality and quality cannot be obtained.

  On the other hand, in the case of the LPE method described in Patent Document 2, the occurrence of micropipe defects and crystal defects as seen in the sublimation recrystallization method is small, and the quality is higher than that produced by the sublimation recrystallization method. Excellent single crystal SiC can be obtained. On the other hand, since the growth process is limited by the solubility of C in the Si melt, the growth rate is very slow, 10 μm / hr or less, and the productivity of single-crystal SiC is low. The temperature must be precisely controlled. In addition, the process becomes complicated, and the manufacturing cost of single crystal SiC becomes very expensive.

The present invention has been made in view of the above problems, and provides a high-quality, high-performance single-crystal SiC having a wide terrace and high surface flatness, with few occurrences of micropipe defects and interface defects. With the goal.
In particular, an object of the present invention is to provide a single-crystal SiC growth method that can provide high-quality and high-performance single-crystal SiC by controlling the film thickness of the growing single-crystal SiC.

Means and effects for solving the problems

In the present invention, a C atom supply substrate for supplying C atoms is superposed on a single crystal SiC substrate to be a seed crystal, and an ultrathin metal Si fusion is provided between the single crystal SiC substrate and the supply substrate. A method for growing single-crystal silicon carbide, comprising liquid-phase epitaxial growth of single-crystal SiC on a single-crystal SiC substrate serving as the seed crystal by performing a heat treatment for a predetermined time at a predetermined temperature of about 1400 ° C. or more with a liquid layer interposed About.
In order to achieve the above object, the present invention has several features as follows. In the present invention, the following features are provided alone or in combination as appropriate.

In order to achieve the above object, the first feature of the present invention is that a C atom supply substrate excluding a polycrystalline SiC base substrate is used as the C atom supply substrate.
For example, as the C atom supply substrate, at least one substrate selected from the group consisting of a carbon substrate, a porous SiC substrate, a sintered SiC substrate, and an amorphous SiC substrate is preferably used.
The C atom supply substrate excluding the polycrystalline SiC substrate has a larger surface energy than the polycrystalline SiC substrate. In particular, carbon can increase the supply amount of C atoms, so that the growth rate can be increased. Further, the C atom supply substrate excluding the polycrystalline SiC substrate is extremely excellent in workability as compared with the polycrystalline SiC substrate, and can be manufactured at a low cost, thereby reducing the manufacturing cost.

The second feature of the present invention for achieving the above object is that a spacer having a thickness of about 50 μm or less is provided between the single crystal SiC substrate and the C atom supply substrate, and the single crystal SiC substrate and the C It is to control the thickness of single crystal SiC grown between the atomic supply substrate.
For example, it is preferable to provide a spacer at least at one location so that the thickness between the single crystal silicon carbide substrate and the C atom supply substrate is uniform. Thereby, the thickness of the single crystal SiC grown between the single crystal SiC substrate and the C atom supply substrate can be made uniform over the entire growth surface.

As an example of the spacer, at least one of the C atom supply substrate and the single crystal SiC substrate may be a convex portion provided by machining so as to protrude toward the metal Si melt layer side.
Further, as another example of the spacer, there is a protrusion bonded to at least one of the C atom supply substrate and the single crystal SiC substrate by a solid phase reaction so as to protrude toward the metal Si melt layer side. Can be mentioned.

  In order to achieve the above object, the third feature of the present invention is that an appropriate pressure is applied to the upper surface of the C atom supply substrate. Thereby, it is possible to make the thickness uniform over the entire surface of the growing single crystal SiC.

According to the growth method of the single crystal silicon carbide described in the second and third above, the thickness of the metal Si melt layer that affects the growth rate can be kept constant during the growth process, and the single crystal SiC substrate and It is possible to appropriately control the thickness of the metal Si melt layer interposed between the C atom supply element substrate. Thereby, the film thickness of the growing single crystal SiC substrate is controlled.
SiC molecules that dissolve from the polycrystalline SiC substrate into the metal Si melt layer can diffuse in the horizontal direction as the thickness of the metal Si melt layer increases.

Therefore, if the thickness of the metal Si melt layer can be appropriately controlled, the uniformity of the liquid crystal epitaxial growth of the single crystal SiC on the surface of the single crystal SiC substrate serving as the seed crystal is dramatically improved.
Therefore, according to the above method, the density of micropipe defects is set so that the step width of the step bunches on the surface of the grown single crystal SiC is on the order of 100 μm, and the step height is set to the minimum unit of half the height of the crystal unit cell. Can be controlled to 1 / cm 2 or less. As a result, it is possible to produce a high-quality single crystal silicon carbide that is flat and has few defects.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, an example of the heat processing apparatus for implementing this embodiment is demonstrated.
FIG. 1 is a schematic cross-sectional view showing an example of a heat treatment apparatus for carrying out the single crystal SiC growth method of the present embodiment.
In FIG. 1, the heat treatment apparatus 1 includes a main heating chamber 2, a preheating chamber 3, and a front chamber 4 that extends from the preheating chamber 3 to the main heating chamber 2. Then, the hermetically sealed container 16 containing the single crystal SiC substrate 5 and the like sequentially moves from the preheating chamber 3 to the front chamber 4 and the main heating chamber 2 so that the single crystal SiC substrate 5 and the like can be moved to about 1400 ° C. in a short time. It can heat at the above predetermined temperature.

  As shown in FIG. 1, in the heat treatment apparatus 1, the main heating chamber 2, the preheating chamber 3, and the front chamber 4 have a communication portion and are partitioned. For this reason, it becomes possible to control each chamber under a predetermined pressure in advance. Further, it is possible to adjust the pressure for each chamber by providing a gate valve 7 or the like for each chamber. As a result, even when the closed container 16 containing the single crystal SiC substrate 5 or the like is moved, the inside of the furnace under a predetermined pressure can be moved by a moving means (not shown) without touching the outside air. Can be suppressed.

The preheating chamber 3 is provided with heating means 6 such as a lamp or a rod heater. In the present embodiment, a halogen lamp 6 is provided. It can be rapidly heated to about 800 ° C. or higher under a reduced pressure of about 10 ⁻⁵ Pa or less. In addition, a gate valve 7 is provided at a connection portion between the preheating chamber 3 and the front chamber 4, and pressure control of the preheating chamber 3 and the front chamber 4 is facilitated.
The sealed container 16 in which the single crystal SiC substrate 5 or the like is stored is preheated to about 800 ° C. or higher in the preheating chamber 3 while being placed on the table 8. After that, as soon as the pressure adjustment between the preheating chamber 3 and the front chamber 4 is completed, the preheating chamber 3 and the front chamber 4 are moved so as to be installed on the liftable susceptor 9 provided in the front chamber 4.

The sealed container 16 moved to the front chamber 4 is moved from the front chamber 4 to the main heating chamber 2 by the lifting / lowering moving means 10 partially shown. The main heating chamber 2 can be adjusted in advance under a reduced pressure of about 10 ⁻¹ Pa or less by a vacuum pump (not shown), and can be heated to about 1400 ° C. or more by the heater 11. In this embodiment, a predetermined temperature of about 1400 ° C. or higher is set in advance under a reduced pressure of about 10 ⁻² Pa or less, preferably about 10 ⁻⁵ Pa or less. Note that the pressure environment in the main heating chamber 2 may be a rare gas atmosphere in which some inert gas is introduced after the pressure environment is about 10 ⁻² Pa or less, preferably about 10 ⁻⁵ Pa or less. .
If the state in the main heating chamber 2 is set in this way, and the sealed container 16 is moved from the front chamber 4 into the main heating chamber 2, the sealed container 16 is rapidly heated to about 1400 ° C. or more rapidly in a short time. be able to.

Further, a heater 11 is disposed in the main heating chamber 2.
The fitting portion 25 between the moving means 10 and the main heating chamber 2 includes a convex stepped portion 21 provided in the moving means 10 and a concave stepped portion 22 formed in the main heating chamber 2. It is configured. The main heating chamber 2 is hermetically sealed by a seal member such as an O-ring (not shown) provided at each step portion of the stepped portion 21 of the moving means 10.

  The heater 11 includes a base heater 11a and an upper heater 11b. The base heater 11a is installed on the susceptor 9. The upper heater 11b is integrally formed with a cylindrical side surface and an upper surface that closes the upper end thereof. Thus, since the heater 11 is disposed so as to cover the sealed container 16, the sealed container 16 can be heated evenly. The heating method of the main heating chamber 2 is not limited to the resistance heater shown in the present embodiment, and may be a high frequency induction heating method, for example.

  With reference to FIGS. 2 to 4, the sealed container 16 and the substrate disposed therein will be described. FIG. 2 shows a perspective view of the sealed container 16, in which the upper container 16a and the lower container 16b are separated from each other. FIG. 3 is a diagram showing the arrangement of the spacers 19 on the single crystal SiC substrate 5 as seen from the upper surface side, and is a diagram showing the inside from the opening provided on the upper surface side of the lower container 16b. FIG. 4 is a cross-sectional view showing a state where the upper container 16a and the lower container 16b of the sealed container 16 are fitted, and a substrate such as the single crystal SiC substrate 5 or the C atom supply substrate 17 for growing single crystal SiC. The arrangement of the spacers 19 is shown.

In the sealed container 16 shown in FIG. 4, the support substrate 24, the single crystal SiC substrate 5, at least one spacer 19, the C atom supply substrate 17, at least one Si substrate 14, and at least one weight stone 23 are arranged in this order. Are stacked from top to bottom. The support substrate 24 is formed of a substrate similar to the C atom supply substrate 17.
FIG. 4 shows a state in which an ultrathin metal Si melt layer 18 is formed in the thickness of the spacer 19 during heat treatment between the single crystal SiC substrate 5 housed in the sealed container 16 and the C atom supply substrate 17. .
Examples of the Si material supply source of the ultrathin metal Si melt layer 18 include Si powder.
The Si thickness of the metal Si melt layer 18 can be controlled by interposing a spacer 19 between the single crystal silicon carbide substrate 5 and the C atom supply substrate 17. .

As the C atom supply substrate 17 and the support substrate 24, a polycrystalline SiC substrate can be used. However, it is preferable to use as the C atom supply substrate 17 or the support substrate 24 at least one substrate selected from the group consisting of a carbon substrate, a porous SiC substrate, a sintered SiC substrate, and an amorphous SiC substrate.
The carbon substrate, the porous SiC substrate, the sintered SiC substrate, and the amorphous SiC substrate have a larger surface energy than the polycrystalline SiC substrate. In particular, the carbon substrate can increase the supply amount of C atoms, so that the growth rate can be increased. Furthermore, the carbon substrate, porous SiC substrate, sintered SiC substrate, and amorphous SiC substrate are extremely excellent in workability as compared with the polycrystalline SiC substrate, and the manufacturing cost can be suppressed because they are inexpensive.
Here, the support substrate 24 located on the lowermost side prevents erosion of the single crystal SiC substrate 5 from the sealed container 16 and contributes to the quality improvement of the single crystal SiC that is liquid phase epitaxially grown on the single crystal SiC substrate 5. To do.

  When a polycrystalline SiC substrate is used as the C atom supply substrate 17 and the support substrate 24, a SiC substrate cut into a desired size from a SiC used as a dummy wafer in a Si semiconductor manufacturing process manufactured by a CVD method is used. be able to. The surfaces of the polycrystalline SiC substrates 17 and 24 are polished to a mirror surface, and oils, oxide films, metals, etc. adhering to the surfaces are removed by washing or the like. The polycrystalline SiC substrates 17 and 24 preferably have an average particle diameter of 5 μm to 10 μm and a substantially uniform particle diameter. Therefore, there is no particular limitation on the crystal structure of polycrystalline SiC, and any of 3C—SiC, 4H—SiC, and 6H—SiC can be used.

Further, at least one Si substrate 14 laminated on the C atom supply substrate 17 is provided to control the sublimation of SiC and the evaporation of Si in the sealed container 16 during the heat treatment. By installing the Si substrate 14, it is melted and sublimated during the heat treatment to increase the SiC partial pressure and the Si partial pressure in the sealed container 16, and the single crystal SiC substrate 5, the C atom supply substrate 17, the support substrate 24, and the ultrathin metal Si This contributes to prevention of sublimation of the melt 18. In addition, the pressure in the sealed container 16 can be adjusted to be higher than the pressure in the preheating chamber 3 and the main heating chamber 2, so that Si vapor can always be supplied from the fitting portion between the upper container 16a and the lower container 16b. It is possible to release the impurities and prevent the impurities from entering the sealed container 16.
Thus, if impurities are prevented from being mixed into the sealed container, single-crystal SiC having a high purity of 5 × 10 ¹⁵ / cm ³ can be produced.
The number and amount of the Si substrates 14 are appropriately determined depending on the degree of sublimation prevention and pressure adjustment.

Between the single crystal SiC substrate 5 and the C atom supply substrate 17, a spacer 19 having a predetermined thickness in a range of about 50 μm or less is provided. Thereby, the thickness of the metal SiC melt layer 18 interposed between the single crystal silicon carbide substrate 5 and the C atom supply substrate 17 can be controlled. The spacer 19 makes it possible to keep the thickness of the metal SiC melt layer 18 constant during the growth of single crystal SiC.
Spacers 19 having substantially the same thickness are installed at least at one place, preferably at three places. Thereby, the thickness of the metal silicon melt layer 18 interposed between the single crystal silicon carbide substrate 5 and the C atom supply substrate 17 can be made substantially uniform. Thereby, the thickness of the obtained growth film can be made uniform over the entire growth surface.

  The number of the spacers 19 is appropriately determined according to the size of the single crystal silicon carbide substrate 5, the C atom supply substrate 17, and the like. As for the shape of the spacer 19, as long as the distance between the single crystal silicon carbide substrate 5 and the C atom supply substrate 17 can be kept constant during the growth process of the single crystal SiC, a cylindrical shape, a rectangular parallelepiped, etc. Various shapes can be applied. In the case of a cylindrical shape, the diameter of the spacer 19 is appropriately determined according to the size of the single crystal silicon carbide substrate 5, the C atom supply substrate 17, and the like. In this embodiment, it is about 3 mmΦ.

The spacer 19 is sandwiched under the C atom supply substrate 17 and the like in order to lift the C atom supply substrate 17 and the like from the single crystal SiC substrate 5.
Further, the spacer 19 is a convex portion provided by machining on at least one of the C atom supply substrate 17 and the single crystal SiC substrate 5 so as to protrude toward the metal Si melt layer 18 side. Also good.
Furthermore, the spacer 19 is a convex portion bonded to at least one of the C atom supply substrate 17 and the single crystal SiC substrate 5 by a solid phase reaction so as to protrude toward the metal Si melt layer 18 side. It may be.

  At least the weight 23 laminated on the Si substrate 14 is provided as necessary. The cobble stone 23 is provided to perform an appropriate pressurization by gravity equally over the entire upper surface of the C atom supply substrate 17. The number and weight of the weights 23 are appropriately determined depending on the degree of pressurization. By the pressurization, the thickness of the metal SiC melt layer 18 interposed between the single crystal silicon carbide substrate 5 and the C atom supply substrate 17 can be controlled by the thickness of the spacer. Note that an appropriate method of pressurizing the upper surface of the C atom supply substrate 17 is not limited thereto.

By adjusting the thickness of the Si material supply source, the thickness of the spacer 19, the appropriate pressure on the upper surface of the C atom supply substrate 17, etc., the single crystal silicon carbide substrate 5 and the C atom supply substrate 17 The thickness of the metal silicon melt layer 18 interposed therebetween can be controlled by the thickness of the spacer.
Further, by adjusting the thickness of the Si material supply source, the thickness of the spacer 19, the appropriate pressure on the upper surface of the C atom supply substrate 17, etc., it is thicker than the desired thickness of single crystal SiC obtained by liquid phase epitaxial growth It is preferable to perform liquid phase epitaxial growth with the metal Si melt layer 18.

The SiC molecules dissolved from the C atom supply substrate 17 into the metal Si melt layer 18 can diffuse in the horizontal direction as the thickness of the metal Si melt layer 18 increases.
When the thickness of the metal Si melt layer 18 interposed between the single crystal SiC substrate 5 and the C atom supply substrate 17 is larger than the desired thickness of the single crystal SiC to be grown, it is preferably heated to 1400 ° C. or higher. When it is as thick as possible within the prescribed temperature and atmosphere conditions,
On the surface of the single crystal SiC substrate 5 serving as the seed crystal, the uniformity of the single crystal SiC growing in the liquid phase epitaxially improves dramatically, and the thickness of the single crystal SiC obtained by the liquid phase epitaxial growth depends on the temperature of the heating chamber. Can be controlled by time and atmospheric pressure.
Therefore, according to the method of controlling the thickness of the metal Si melt layer 18, the step bunch terrace width on the surface of the grown single crystal silicon carbide is set to the order of 100 μm, and the step height is the minimum unit of the half height of the crystal unit cell. The density of micropipe defects can be controlled to 1 / cm 2 or less. As a result, it is possible to produce a high-quality single crystal silicon carbide that is flat and has few defects.
The terrace refers to a step having a wide width among a plurality of steps.

  In addition, since single crystal SiC obtained by the single crystal SiC growth method according to the present embodiment has few crystal defects and the like, it can be used as a light emitting diode, various semiconductor diodes, and electronic devices. In addition, strict temperature control in the processing furnace because crystal growth does not depend on the temperature difference between the seed crystal and the C source crystal, but depends on the surface energy of the seed crystal and the C source crystal. Therefore, the manufacturing cost can be greatly reduced. Furthermore, since the distance from the single crystal SiC and C atom supply substrate to be the seed crystal is very small, thermal convection during heat treatment can be suppressed. In addition, since a temperature difference is hardly formed between the single crystal SiC and C atom supply substrate to be a seed crystal, the heat treatment can be performed in a thermal equilibrium state.

In this embodiment, 4H—SiC is used as a seed crystal, but 6H—SiC can also be used. Furthermore, in the present embodiment, the (0001) Si plane is used as the seed crystal, but it is also possible to use other plane orientations such as the (0001) C plane and (11-20).
In addition, the single crystal SiC according to the present invention can control the size of the single crystal SiC formed as a seed crystal by appropriately selecting the size of the single crystal SiC and the C atom supply substrate. In addition, since no distortion is formed between the single crystal SiC to be formed and the seed crystal, single crystal SiC having a very smooth surface can be obtained. Therefore, it can be applied as a modified film on the surface.

Schematic sectional view showing an example of a heat treatment apparatus for carrying out the present embodiment The figure which shows the structure of the airtight container in the heat processing apparatus of FIG. FIG. 2 is a plan view showing an example of spacer arrangement on a single crystal SiC substrate in the sealed container of FIG. Sectional drawing which shows the example of arrangement | positioning of the spacer, SiC substrate, etc. on the single crystal SiC substrate in the airtight container of FIG.

Explanation of symbols

1 Heat treatment equipment
2 heating chambers
3 Preheating chamber
4 Front room
5 Single crystal SiC substrate
6 Halogen lamp
7 Gate valve
8 tables
9 Susceptor
10 Means of transportation
11 Heating heater
14 Molten Si at high temperature (Metal Si substrate at low temperature)
16 Airtight container
17 C atom supply substrate
18 Si melt layer at high temperature (Si powder at low temperature)
19 Spacer
23 Cobblestone
24 Support substrate
25 Mating part

Claims (7)

A carbon atom supply substrate for supplying carbon atoms is stacked on a single crystal silicon carbide substrate to be a seed crystal, and an ultrathin metal silicon melt layer is provided between the single crystal silicon carbide substrate and the carbon atom supply substrate. A method of growing single crystal silicon carbide by liquid phase epitaxial growth of single crystal silicon carbide on the single crystal silicon carbide substrate serving as the seed crystal by performing heat treatment for a predetermined time at a predetermined temperature of about 1400 ° C. Because
A single crystal silicon carbide growth method using a carbon atom supply substrate excluding a polycrystalline silicon carbide substrate as the carbon atom supply substrate.   The single crystal carbonization according to claim 1, wherein at least one substrate selected from the group consisting of a carbon substrate, a porous silicon carbide substrate, a sintered silicon carbide substrate, and an amorphous silicon carbide C substrate is used as the carbon atom supply substrate. Silicon growth method. A carbon atom supply substrate for supplying carbon atoms is stacked on a single crystal silicon carbide substrate to be a seed crystal, and an ultrathin metal silicon melt layer is disposed between the single crystal silicon carbide substrate and the carbon atom supply substrate. A method of growing single crystal silicon carbide by liquid phase epitaxial growth of single crystal silicon carbide on the single crystal silicon carbide substrate serving as the seed crystal by performing heat treatment for a predetermined time at a predetermined temperature of about 1400 ° C. Because
A spacer having a thickness of about 50 μm or less is provided between the single crystal silicon carbide substrate and the polycrystalline silicon carbide substrate,
A method for growing a single crystal silicon carbide, wherein the thickness of the single crystal silicon carbide grown between the single crystal silicon carbide substrate and the carbon atom supply substrate is controlled.   The method for growing single crystal silicon carbide according to claim 3, wherein a spacer is provided in at least one place so that the thickness between the single crystal silicon carbide substrate and the carbon atom supply substrate is substantially uniform.   The spacer is a protrusion provided by machining on at least one of the carbon atom supply substrate and the single crystal silicon carbide substrate so as to protrude toward the metal silicon melt layer side. The method for growing single crystal silicon carbide according to any one of the above.   The spacer is a protrusion bonded to at least one of the carbon atom supply substrate and the single crystal silicon carbide substrate by a solid phase reaction so as to protrude toward the metal silicon melt layer side. 5. The method for growing single crystal silicon carbide according to any one of 4 above. 7. The thickness of the single crystal silicon carbide grown between the single crystal silicon carbide substrate and the carbon atom supply substrate is controlled by applying an appropriate pressure to the upper surface of the carbon atom supply substrate. A method for growing single crystal silicon carbide according to claim 1.

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