JP5724121B2 - Feed material for epitaxial growth of single crystal silicon carbide and epitaxial growth method of single crystal silicon carbide - Google Patents

Description

  The present invention relates to a feed material for epitaxial growth of single crystal silicon carbide and a method for epitaxial growth of single crystal silicon carbide using the same.

  Silicon carbide (SiC) can realize high temperature resistance, high voltage resistance, high frequency resistance, and high environmental resistance that cannot be realized by conventional semiconductor materials such as silicon (Si) and gallium arsenide (GaAs). It is believed that. For this reason, silicon carbide is expected as a semiconductor material for next-generation power devices and a semiconductor material for high-frequency devices.

  Conventionally, as a method for growing single crystal silicon carbide, for example, the following Patent Document 1 proposes a sublimation recrystallization method (an improved Rayleigh method). In this improved Rayleigh method, a seed material made of single-crystal silicon carbide is disposed in the low temperature side region in the crucible, and a raw material powder containing Si as a raw material is disposed in the high temperature side region. And after making the inside of a crucible into inert atmosphere, the raw material powder arrange | positioned in the high temperature side area | region is sublimated by heating to the high temperature of 1450 to 2400 degreeC. As a result, silicon carbide can be epitaxially grown on the surface of the seed material disposed in the low temperature region.

  However, the improved Rayleigh method is a method of growing silicon carbide crystals by providing a temperature gradient in the gas phase. For this reason, when the improved Rayleigh method is used, a large apparatus is required for epitaxial growth of silicon carbide, and process control of silicon carbide epitaxial growth becomes difficult. Therefore, there is a problem that the manufacturing cost of the silicon carbide epitaxial growth film is increased. Also, silicon carbide epitaxial growth in the gas phase is non-equilibrium. For this reason, there are problems that crystal defects are likely to occur in the formed silicon carbide epitaxially grown film and that the crystal structure is likely to be rough.

  As an epitaxial growth method of silicon carbide other than the modified Rayleigh method, for example, there is a metastable solvent epitaxy (MSE) method proposed in Patent Document 2 or the like, which is a method of epitaxially growing silicon carbide in a liquid phase. .

  In the MSE method, a seed material made of crystalline silicon carbide such as single crystal silicon carbide or polycrystalline silicon carbide and a feed material made of silicon carbide are opposed to each other with a small interval of, for example, 100 μm or less, and Si is interposed therebetween. A molten layer is interposed. And silicon carbide is epitaxially grown on the surface of the seed material by heat treatment in a vacuum high temperature environment.

  In this MSE method, it is considered that a silicon carbide epitaxial growth film is formed by the concentration gradient of carbon dissolved in the Si melt layer due to the difference between the chemical potential of the seed material and the chemical potential of the feed material. It has been. For this reason, unlike the case of using the improved Rayleigh method, it is not always necessary to provide a temperature difference between the seed material and the feed material. Therefore, when the MSE method is used, the silicon carbide epitaxial growth process can be easily controlled with a simple apparatus, and a high-quality silicon carbide epitaxial growth film can be stably formed.

  In addition, an advantage that a silicon carbide epitaxial growth film can be formed on a seed substrate having a large area, and since the Si melt layer is extremely thin, carbon from the feed material is easily diffused, and the temperature of the epitaxial growth process of silicon carbide can be reduced. There is also an advantage.

  Therefore, the MSE method is considered to be an extremely useful method as an epitaxial growth method of single crystal silicon carbide, and research on the MSE method is actively conducted.

Japanese Patent Laid-Open No. 2005-97040 JP 2008-230946 A

  As described above, in the MSE method, it is considered that the feed material and the seed material need to be selected so that the free energy of the feed material is higher than the free energy of the seed material. For this reason, for example, Patent Document 2 describes that the free energy is made different between the feed substrate and the seed substrate by making the crystal polymorph of the feed substrate and the seed substrate different. Specifically, it is described that when the feed substrate is constituted by a polycrystalline 3C-SiC substrate, the seed substrate is constituted by a single crystal 4H-SiC substrate having a lower free energy than that of the 3C-SiC substrate. .

  Here, the polycrystalline 3C-SiC substrate can be easily manufactured by a CVD method. For this reason, as described in Patent Document 2, by using a 3C—SiC substrate as a feed substrate, the formation cost of the silicon carbide epitaxial growth film can be kept low. Therefore, the present inventor has advanced research on using a 3C—SiC substrate as a feed substrate. As a result, it has been found that some 3C-SiC substrates include silicon carbide having a high epitaxial growth rate and a slow one.

  This invention is made | formed in view of the point which concerns, The objective is to provide the feed material for single-crystal silicon carbide epitaxial growth which can make a silicon carbide epitaxial growth rate high.

  As a result of intensive studies, the present inventor has found that the epitaxial growth rate when using a feed material having a crystal polymorphism of 3C correlates with the orientation angle of the (111) crystal plane. Specifically, the present inventors have found that the smaller the (111) crystal plane with a high orientation angle, the higher the epitaxial growth rate. As a result, the present inventor came to make the present invention.

  That is, the feed material for epitaxial growth of single crystal silicon carbide according to the present invention is a feed material used for the epitaxial growth method of single crystal silicon carbide. The feed material for epitaxial growth of single crystal silicon carbide according to the present invention has a surface layer containing polycrystalline silicon carbide whose crystal polymorph is 3C. A diffraction peak corresponding to the (111) crystal plane is observed by X-ray diffraction of the surface layer. Of the (111) crystal planes observed by X-ray diffraction of the surface layer, the proportion of those having an orientation angle of 67.5 ° or more is less than 80%. For this reason, the epitaxial growth rate of single crystal silicon carbide can be effectively increased. This is because the degree of exposure of the surface having a lower stability than the (111) crystal plane of the crystal exposing the (111) crystal plane is high, and the reactivity of the crystal exposing the (111) crystal plane is high. It is thought that it is because it becomes high.

  The first-order diffraction peak corresponding to the (111) crystal plane is preferably the main diffraction peak having the largest diffraction intensity among the first-order diffraction peaks corresponding to polycrystalline silicon carbide having a crystal polymorph of 3C.

  In the present invention, the “epitaxial growth method” includes a liquid phase epitaxial growth method such as a metastable solvent epitaxy (MSE) method and a vapor phase epitaxial growth method such as an improved Rayleigh method. The “MSE method” is a method in which a seed material and a feed material are heated in a state of being opposed to each other through a silicon melt layer, thereby forming a concentration gradient of graphite that melts in the silicon melt layer. A method of epitaxially growing single crystal silicon carbide on a material.

In the present invention, “X-ray diffraction” refers to diffraction using X-rays (CuK _α- rays) of 8.048 keV.

  In the present invention, a “feed material” refers to a member that supplies a material for epitaxial growth of single crystal silicon carbide such as Si, C, and SiC. On the other hand, the “seed material” refers to a member in which single crystal silicon carbide grows on the surface.

  In the present invention, the surface layer preferably contains polycrystalline silicon carbide having a crystal polymorphism of 3C as a main component, and is preferably substantially composed of polycrystalline silicon carbide having a crystal polymorphism of 3C. According to this configuration, the epitaxial growth rate of single crystal silicon carbide can be further effectively increased.

  In the present invention, the “main component” refers to a component contained by 50% by mass or more.

  In the present invention, “substantially consists of polycrystalline silicon carbide whose crystal polymorph is 3C” means that it contains no components other than impurities other than polycrystalline silicon carbide whose crystal polymorph is 3C. To do. Usually, the impurity contained in the case of “substantially consisting of polycrystalline silicon carbide whose crystal polymorph is 3C” is 5% by mass or less.

  The feed material for epitaxial growth of single crystal silicon carbide according to the present invention may include a support material and a polycrystalline silicon carbide film that is formed on the support material and forms a surface layer. In that case, the thickness of the polycrystalline silicon carbide film is preferably in the range of 30 μm to 800 μm.

  Moreover, the feed material for single crystal silicon carbide epitaxial growth according to the present invention may be composed of a polycrystalline silicon carbide material containing polycrystalline silicon carbide having a crystal polymorph of 3C.

  In the single crystal silicon carbide epitaxial growth method according to the present invention, single crystal silicon carbide is epitaxially grown using the single crystal silicon carbide epitaxial growth feed material according to the present invention. Therefore, single crystal silicon carbide can be epitaxially grown at a high rate.

  In the method for epitaxial growth of single-crystal silicon carbide according to the present invention, the seed material is heated by heating the surface layer of the feed material and the surface layer of the seed material having a surface layer made of silicon carbide through the silicon fusion layer. It is preferable to epitaxially grow single crystal silicon carbide on the surface layer. That is, the single crystal silicon carbide epitaxial growth method according to the present invention is preferably a single crystal silicon carbide liquid phase epitaxial growth method. In this case, it is not always necessary to provide a temperature difference between the seed material and the feed material. Therefore, the single crystal silicon carbide epitaxial growth process can be easily controlled with a simple apparatus, and a high-quality single crystal silicon carbide epitaxial growth film can be stably formed.

  ADVANTAGE OF THE INVENTION According to this invention, the feed material for single-crystal silicon carbide epitaxial growth which can make a silicon carbide epitaxial growth rate high can be provided.

It is a schematic diagram for demonstrating the epitaxial growth method of the single crystal silicon carbide in one Embodiment of this invention. It is a schematic sectional drawing of the feed board | substrate in one Embodiment of this invention. 1 is a schematic cross-sectional view of a seed substrate in an embodiment of the present invention. It is a schematic sectional drawing of the feed board | substrate in a modification. It is schematic-drawing sectional drawing of the seed substrate in a modification. It is an X-ray diffraction chart of samples 1 to 4. It is a schematic diagram for demonstrating the measuring method of the orientation of a (111) crystal plane. 4 is a graph showing the orientation of (111) crystal plane in Sample 1. 4 is a graph showing the orientation of (111) crystal plane in Sample 2. 4 is a graph showing the orientation of (111) crystal plane in Sample 3. 6 is a graph showing the orientation of a (111) crystal plane in Sample 4. It is a graph which shows the growth rate of the single crystal silicon carbide epitaxial growth film in samples 1, 2 and 4. 5 is a graph showing the growth rate of single crystal silicon carbide epitaxial growth films in samples 3 and 4. FIG.

  Hereinafter, an example of the preferable form which implemented this invention is demonstrated. However, the following embodiments are merely examples. The present invention is not limited to the following embodiments.

  FIG. 1 is a schematic diagram for explaining an epitaxial growth method of single crystal silicon carbide in the present embodiment.

  In the present embodiment, an example of forming an epitaxially grown film of single crystal silicon carbide using the MSE method will be described.

  In the present embodiment, as shown in FIG. 1, in a container 10, a seed substrate 12 as a seed material and a feed substrate 11 as a feed material are combined with a main surface 12 a of the seed substrate 12 and a main surface of the feed substrate 11. It arrange | positions so that 11a may oppose through a silicon plate. In this state, the seed substrate 12 and the feed substrate 11 are heated to melt the silicon plate. By doing so, the seed substrate 12 and the feed substrate 11 are opposed to each other with the silicon melt layer 13 therebetween. By maintaining this state, raw materials such as silicon, carbon and silicon carbide are eluted from the seed substrate 12 side into the silicon melt layer 13. As a result, a concentration gradient is formed in the silicon melt layer 13. As a result, single crystal silicon carbide is epitaxially grown on main surface 12a of seed substrate 12, and single crystal silicon carbide epitaxial growth film 20 is formed. In addition, the thickness of the silicon molten layer 13 is very thin, for example, can be about 10 μm to 100 μm.

(Feed substrate 11)
FIG. 2 shows a schematic cross-sectional view of the feed substrate 11. The feed substrate 11 has a surface layer containing polycrystalline silicon carbide whose crystal polymorph is 3C. Specifically, in this embodiment, the feed substrate 11 has a support material 11b made of graphite and a polycrystalline silicon carbide film 11c. The support material 11b made of graphite has high heat resistance that can sufficiently withstand the epitaxial growth process of silicon carbide. The support material 11b made of graphite has a thermal expansion coefficient similar to that of the single crystal silicon carbide epitaxial growth film 20. Therefore, the silicon carbide epitaxial growth film 20 can be suitably formed by using the support material 11b made of graphite.

  Specific examples of graphite include natural graphite, artificial graphite, petroleum coke, coal coke, pitch coke, carbon black, and mesocarbon. Examples of the method for producing the support material 11b made of graphite include the production method described in JP-A-2005-132711.

  Polycrystalline silicon carbide film 11c is formed so as to cover the main surface and side surfaces of support material 11b. Polycrystalline silicon carbide film 11c includes polycrystalline silicon carbide. The surface layer of the feed substrate 11 is formed by the polycrystalline silicon carbide film 11c. Polycrystalline silicon carbide film 11c preferably includes polycrystalline silicon carbide having a crystal polymorphism of 3C (hereinafter referred to as “polycrystalline 3C-SiC”) as a main component, and is substantially polycrystalline 3C. -SiC is preferable. That is, the surface layer of the feed substrate 11 preferably contains polycrystalline 3C—SiC as a main component, and is preferably substantially made of polycrystalline 3C—SiC. By doing so, the growth rate of the single crystal silicon carbide epitaxial growth film 20 can be increased.

  Thickness t11 of polycrystalline silicon carbide film 11c is preferably in the range of 30 μm to 800 μm, more preferably in the range of 40 μm to 600 μm, and still more preferably in the range of 100 μm to 300 μm. If the thickness t11 of the polycrystalline silicon carbide film 11c is too thin, the support material 11b made of graphite is exposed when the single crystal silicon carbide epitaxial growth film 20 is formed, and suitable single crystal carbonization due to elution from the support material 11b. The silicon epitaxial growth film 20 may not be obtained. On the other hand, if the thickness t11 of the polycrystalline silicon carbide film 11c is too thick, cracks may easily occur in the polycrystalline silicon carbide film 11c.

  The method for forming polycrystalline silicon carbide film 11c is not particularly limited. The polycrystalline silicon carbide film 11c can be formed by, for example, a CVD (Chemical Vapor Deposition) method or a sputtering method. In particular, in this embodiment, since the polycrystalline silicon carbide film 11c contains polycrystalline 3C-SiC, a dense polycrystalline silicon carbide film 11c can be formed easily and inexpensively by the CVD method.

  Polycrystalline silicon carbide film 11c constituting the surface layer of feed substrate 11 accounts for less than 80% of the (111) crystal plane observed by X-ray diffraction with an orientation angle of 67.5 ° or more. It is what is. For this reason, the epitaxial growth rate of single crystal silicon carbide can be effectively increased. This is because the degree of exposure of the surface having a lower stability than the (111) crystal plane of the crystal exposing the (111) crystal plane is high, and the reactivity of the crystal exposing the (111) crystal plane is high. It is thought that it is because it becomes high.

  The first-order diffraction peak corresponding to the (111) crystal plane is preferably the main diffraction peak having the largest diffraction intensity among the first-order diffraction peaks corresponding to polycrystalline silicon carbide having a crystal polymorph of 3C.

(Seed substrate 12)
The seed substrate 12 is not particularly limited as long as the surface layer on the main surface 12a side is made of silicon carbide and is less likely to elute into the silicon melt layer 13 than the feed substrate 11. For example, the seed substrate 12 may be made of a single-crystal silicon carbide surface layer, or may be made of silicon carbide whose crystal polymorph is 4H, 6H, or the like. In addition, the seed substrate 12 includes, for example, polycrystalline silicon carbide whose surface polycrystal is 3C, and the orientation angle is 67.5 out of the (111) crystal plane observed by X-ray diffraction of the surface layer. It may be that the proportion of what is more than 80 ° is 80% or more. In this case, the seed substrate 12 can be manufactured at low cost by the CVD method. Therefore, the formation cost of the single crystal silicon carbide epitaxial growth film 20 can be reduced.

  In the present embodiment, an example using the seed substrate 12 shown in FIG. 3 will be described below. As shown in FIG. 3, in this embodiment, the seed substrate 12 includes a support material 12b made of graphite and a polycrystalline silicon carbide film 12c. The support 12b made of graphite has high heat resistance that can sufficiently withstand the epitaxial growth process of silicon carbide. The support material 12b made of graphite has a thermal expansion coefficient similar to that of the single crystal silicon carbide epitaxial growth film 20. Therefore, silicon carbide epitaxial growth film 20 can be suitably formed by using support material 12b made of graphite.

  Specific examples of graphite include natural graphite, artificial graphite, petroleum coke, coal coke, pitch coke, carbon black, and mesocarbon. Examples of the method for producing the support material 12b made of graphite include the production method described in JP-A-2005-132711.

  Polycrystalline silicon carbide film 12c is formed to cover the main surface and side surfaces of support material 12b. Polycrystalline silicon carbide film 12c includes polycrystalline silicon carbide. The surface layer of the seed substrate 12 is formed by the polycrystalline silicon carbide film 12c. Note that the polycrystalline silicon carbide film 12c in the present embodiment preferably includes polycrystalline 3C—SiC as a main component, and is preferably substantially composed of polycrystalline 3C—SiC. That is, in the present embodiment, the surface layer of the seed substrate 12 preferably includes polycrystalline 3C—SiC as a main component, and is preferably substantially composed of polycrystalline 3C—SiC. By doing so, the growth rate of the single crystal silicon carbide epitaxial growth film 20 can be increased.

  Thickness t12 of polycrystalline silicon carbide film 12c is preferably in the range of 30 μm to 800 μm, more preferably in the range of 40 μm to 600 μm, and still more preferably in the range of 100 μm to 300 μm. If the thickness t12 of the polycrystalline silicon carbide film 12c is too thin, the support material 12b made of graphite is exposed when the single crystal silicon carbide epitaxial growth film 20 is formed, and suitable single crystal carbonization due to elution from the support material 12b. The silicon epitaxial growth film 20 may not be obtained. On the other hand, if the thickness t12 of the polycrystalline silicon carbide film 12c is too thick, cracks may easily occur in the polycrystalline silicon carbide film 12c.

  The method for forming polycrystalline silicon carbide film 12c is not particularly limited. The polycrystalline silicon carbide film 12c can be formed by, for example, a CVD (Chemical Vapor Deposition) method or a sputtering method. In particular, in this embodiment, since the polycrystalline silicon carbide film 12c contains polycrystalline 3C-SiC, a dense polycrystalline silicon carbide film 12c can be easily and inexpensively formed by the CVD method.

  In the above-described embodiment, an example in which each of the feed substrate 11 and the seed substrate 12 is configured by the support materials 11b and 12b and the polycrystalline silicon carbide films 11c and 12c has been described. However, the present invention is not limited to this configuration. For example, as shown in FIG. 4, the feed substrate 11 may be formed of a polycrystalline silicon substrate containing polycrystalline silicon carbide whose crystal polymorph is 3C. Further, as shown in FIG. 5, seed substrate 12 may be formed of a silicon carbide substrate containing silicon carbide.

  The silicon carbide substrate can be produced, for example, by coating a graphite base material with polycrystalline silicon carbide by a CVD method and then mechanically or chemically removing the graphite. The silicon carbide substrate can also be produced by reacting a graphite material with a silicate gas to convert the graphite material into silicon carbide. The silicon carbide substrate can also be produced by adding a sintering aid to silicon carbide powder and sintering at a high temperature of 1600 ° C. or higher.

  In the above embodiment, an example in which a single crystal silicon carbide epitaxial growth film is formed by the MSE method which is a liquid phase epitaxial growth method of single crystal silicon carbide has been described. However, the present invention is not limited to this. For example, the single crystal silicon carbide epitaxial growth film may be formed by a vapor phase epitaxial growth method such as an improved Rayleigh method.

  Hereinafter, the present invention will be further described based on specific examples, but the present invention is not limited to the following specific examples.

(Production Example 1)
A graphite material (15 mm × 15 mm × 2 mm) made of high purity isotropic graphite material having a bulk density of 1.85 g / cm ³ and an ash content of 5 ppm or less was used as a base material. This base material was put in a CVD reactor, and a polycrystalline silicon carbide film having a thickness of 30 μm was formed on the base material by a CVD method to prepare Sample 1. Note that silicon tetrachloride and propane gas were used as the source gas. Film formation was performed at normal pressure and 1200 ° C. The deposition rate was 30 μm / h.

(Production Example 2)
A sample 2 was produced by forming a 50 μm polycrystalline silicon carbide film on the surface of the graphite material in the same manner as in Production Example 1 except that the reaction temperature was 1400 ° C. and the film formation rate was 60 μm / h. .

(Production Example 3)
Polycrystalline 50 μm on the surface of the graphite material in the same manner as in Preparation Example 1 except that the reaction temperature was 1250 ° C., the film formation rate was 10 μm / h, and CH ₃ SiCl ₃ was used instead of silicon tetrachloride. A silicon carbide coating was formed to prepare Sample 3.

(Production Example 4)
Graphite was prepared in the same manner as in Preparation Example 1 except that dichlorosilane (SiH ₂ Cl ₂ ) and acetylene were used instead of silicon tetrachloride and propane gas, the reaction temperature was 1300 ° C., and the film formation rate was 10 μm / h. A sample 4 was prepared by forming a 50 μm polycrystalline silicon carbide coating on the surface of the material. In Sample 4, the thickness of the polycrystalline silicon carbide film was about 1 mm.

(X-ray diffraction measurement)
X-ray diffraction was performed on the surface layers of Samples 1 to 4 prepared above. X-ray diffraction was performed using Rigak Ultima. The measurement results are shown in FIG. Also, the relative intensities of the diffraction peaks corresponding to each crystal plane when the intensity of the observed diffraction peak and the first-order diffraction peak corresponding to the (111) crystal plane are set to 100 in samples 1 to 4 are summarized.

(Evaluation of orientation of (111) crystal plane)
Next, for Samples 1 to 4, as shown in FIG. 7, the angle at which the diffraction peak of the (111) plane appears was measured while rotating the sample. The results are shown in FIGS. In the graphs shown in FIGS. 8 to 11, the horizontal axis is the orientation angle (α) shown in FIG. 7. The vertical axis is intensity.

  Table 2 below shows the ratio of the intensity integral value of the region where the orientation angle (α) is 67.5 ° or more with respect to the intensity integral value of the entire region when the orientation angle (α) is 15 ° to 90 ° ((orientation angle (Α) is the integrated intensity value of the region where 67.5 ° or more) / (intensity integrated value of the entire region when the orientation angle (α) is 15 ° to 90 °)). In addition, ((intensity integrated value of region where orientation angle (α) is 67.5 ° or more) / (intensity integrated value of whole region when orientation angle (α) is 15 ° to 90 °)) is obtained by X-ray diffraction. This corresponds to the proportion of the observed (111) crystal plane with an orientation angle of 67.5 ° or more.

  As shown in FIGS. 8 and 9 and Table 2 above, in Samples 1 and 2, there is a large intensity distribution even in the region where the orientation angle (α) is less than 67.5 °, and among the (111) crystal planes, The ratio of those having an orientation angle (α) of 67.5 ° or more was less than 80%. On the other hand, in Samples 3 and 4, as shown in FIGS. 10 and 11 and Table 2 above, there is no large intensity distribution in the region where the orientation angle (α) is less than 67.5 °. The ratio of α) being 67.5 ° or more was 80% or more.

(Growth rate evaluation of single crystal silicon carbide liquid phase epitaxial growth film)
Using the liquid phase epitaxial growth method described in the above embodiment, a single crystal silicon carbide epitaxial growth film 20 was produced under the following conditions using Samples 1 to 4 as a feed substrate. And the thickness of the silicon carbide epitaxial growth film | membrane 20 was measured by observing the cross section of the silicon carbide epitaxial growth film | membrane 20 using an optical microscope. The growth rate of the single crystal silicon carbide epitaxial growth film 20 was determined by dividing the measured thickness by the time during which the silicon carbide epitaxial growth was performed.

  The results are shown in FIGS. 12 and 13, the vertical axis represents the growth rate of the single crystal silicon carbide epitaxial growth film 20, and the horizontal axis represents the reciprocal (1 / L) of the thickness (L) of the silicon melt layer 13.

  From the results shown in FIGS. 12 and 13, when Samples 1 and 2 in which the ratio of the orientation angle (α) is 67.5 ° or more was less than 80%, the single crystal silicon carbide epitaxial growth film 20 The growth rate was high. On the other hand, when Samples 3 and 4 having an orientation angle (α) of 67.5 ° or more and a ratio of 80% or more were used, the growth rate of single crystal silicon carbide epitaxial growth film 20 was low.

(Measurement conditions of growth rate of single crystal silicon carbide epitaxial growth film 20)
Seed substrate: silicon carbide substrate with crystal polymorph 4H atmosphere pressure: 10 ⁻⁶ to 10 ⁻⁴ Pa
Atmospheric temperature: 1900 ° C

DESCRIPTION OF SYMBOLS 10 ... Container 11 ... Feed substrate 11a ... Main surface 11b ... Support material 11c ... Polycrystalline silicon carbide film 12 ... Seed substrate 12a ... Main surface 12b ... Support material 12c ... Polycrystalline silicon carbide film 13 ... Silicon molten layer 20 ... Single crystal Silicon carbide epitaxial growth film

Claims (9)

Oite epitaxial growth method of a single crystal silicon carbide, a feed material used by the seed material and face each other with a silicon melt layer,
Having a surface layer comprising polycrystalline silicon carbide having a crystalline polymorph of 3C;
A diffraction peak corresponding to the (111) crystal plane is observed by X-ray diffraction of the surface layer,
A feed material for epitaxial growth of single-crystal silicon carbide, wherein the proportion of the (111) crystal planes observed by X-ray diffraction of the surface layer having an orientation angle of 67.5 ° or more is less than 80%.   The first-order diffraction peak corresponding to the (111) crystal plane is a main diffraction peak having the largest diffraction intensity among the first-order diffraction peaks corresponding to polycrystalline silicon carbide whose crystal polymorph is 3C. Item 2. A feed material for epitaxial growth of single crystal silicon carbide according to Item 1.   3. The feed material for epitaxial growth of single crystal silicon carbide according to claim 1, wherein the surface layer contains, as a main component, polycrystalline silicon carbide whose crystal polymorph is 3C.   The feed material for single crystal silicon carbide epitaxial growth according to claim 3, wherein the surface layer is substantially made of polycrystalline silicon carbide having a crystal polymorphism of 3C.   The single crystal silicon carbide epitaxial growth according to any one of claims 1 to 4, comprising a support material and a polycrystalline silicon carbide film formed on the support material and constituting the surface layer. Feed material.   The feed material for single crystal silicon carbide epitaxial growth according to claim 5, wherein the polycrystalline silicon carbide film has a thickness in a range of 30 μm to 800 μm.   The feed material for single-crystal silicon carbide epitaxial growth according to any one of claims 1 to 4, wherein the feed material is a polycrystalline silicon carbide material containing polycrystalline silicon carbide having a crystal polymorph of 3C.   The epitaxial growth method of a single crystal silicon carbide using the feed material for single crystal silicon carbide epitaxial growth as described in any one of Claims 1-7.   The single crystal silicon carbide is epitaxially grown on the surface layer of the seed material by heating the surface layer of the feed material and the surface layer of the seed material having a surface layer made of silicon carbide with the silicon melt layer facing each other. The method for epitaxial growth of single crystal silicon carbide according to claim 8.