JP4521588B2 - Method for producing single crystal SiC film - Google Patents

Description

  The present invention relates to a method for producing a single crystal SiC film.

  SiC (silicon carbide; silicon carbide) is (i) excellent in heat resistance and mechanical strength, (ii) resistant to radiation, and (iii) valence electron control of electrons and holes is easy by addition of impurities. It is expected to be a semiconductor material for next-generation power devices and high-frequency devices because it has such characteristics as (iv) wide forbidden bandwidth.

  However, the single crystal SiC substrate has a problem that crystal defects such as basal plane dislocations, spiral dislocations, and micropipes tend to be inherent due to the influence of heat, and crystal grain boundaries due to nucleation are likely to occur.

  For this reason, when an active layer made of single crystal SiC is generated on a single crystal SiC substrate by a vapor phase growth method which is currently mainstream as an SiC epitaxial growth method, crystal defects and the like inherent in the single crystal SiC substrate propagate to the active layer. There is a problem of end.

Therefore, for example, in Patent Documents 1 to 3, a liquid for epitaxially growing single crystal SiC by performing a heat treatment in a state where a metal Si (silicon) melt is interposed between the single crystal SiC substrate and the polycrystalline SiC substrate. Phase epitaxial technology (hereinafter referred to as MSE (Metastable Solvent Epitaxy) method) is disclosed. In addition, the production method of single crystal SiC disclosed in Patent Documents 1 to 3 has an advantage that single crystal SiC with high flatness with suppressed micropipe defects can be realized and the growth rate is high. .
WO2002 / 099169 (Publication date: December 12, 2002) JP 2005-126248 A (Publication date: May 19, 2005) JP 2005-126249 A (Publication date: May 19, 2005)

  However, in the techniques of Patent Documents 1 to 3, since the metal Si melt sandwiched between the single crystal SiC substrate and the polycrystalline SiC substrate is structurally unstable, the single crystal SiC substrate and the polycrystal are grown in the growth process. There is a problem in that a position shift from the SiC substrate occurs, a single crystal SiC growth region becomes non-uniform, and an unformed region where a single crystal SiC film is not formed on the substrate surface of the single crystal SiC is generated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to store a laminated structure including a single crystal SiC substrate and a carbon raw material supply plate in a container, and to form the surface of the single crystal SiC substrate. A method of manufacturing a single crystal SiC film, in which a single crystal SiC film is epitaxially grown on the single crystal SiC substrate by performing a heat treatment in a state where the Si melt layer is in contact with the single crystal SiC substrate and the polycrystalline SiC An object of the present invention is to provide a method for producing a single crystal SiC film capable of growing a single crystal SiC film over substantially the entire substrate surface of the single crystal SiC substrate while suppressing displacement with respect to the substrate.

  In order to solve the above-described problems, the method for producing a single crystal SiC film of the present invention stores a laminated structure including at least a single crystal SiC substrate and a carbon raw material supply plate in a first container, and the first container is Then, it is housed in a second container that can be hermetically sealed, and heat treatment is performed in a state where the Si melt layer is in contact with the surface of the single crystal SiC substrate. A method for producing a single crystal SiC film by epitaxially growing a crystalline SiC film, the direction being parallel to an in-plane direction of the single crystal SiC substrate and the carbon raw material supply plate when the stacked structure in the first container is accommodated The difference between the inner dimension of the first crystal SiC substrate and the outer dimension in the direction parallel to the direction of the inner dimension when accommodated in the first container of the carbon raw material supply plate is 0.5 mm or more. . Is characterized in that the mm or less.

  According to said structure, when the said laminated structure in the said 1st container is accommodated, the internal dimension of the direction parallel to the surface direction of the said single crystal SiC substrate and the said carbon raw material supply board, and the said single crystal SiC When the substrate and the carbon raw material supply plate are accommodated in the first container, the difference between the outer dimension in a direction parallel to the direction of the inner dimension is set to 2.0 mm or less, thereby stacking with the Si melt layer. Even if the stacked state of each member constituting the structure becomes unstable, the movement of the single crystal SiC substrate and the carbon raw material supply plate in the in-plane direction is restricted by the first container, and the single crystal SiC substrate and the carbon raw material supply plate are controlled. Can be suppressed. Thereby, a single crystal SiC film can be grown on almost the entire surface of the single crystal SiC substrate without generating an ungrown region. Moreover, the said laminated structure can be easily accommodated in a 1st container by making said difference into 0.5 mm or more. Moreover, it can suppress that a single crystal SiC substrate cracks by heat processing.

  Further, the difference may be set to 1.0 mm or more and 2.0 mm or less.

  According to said structure, accommodation in the 1st container of the said laminated structure can be made still easier. In addition, it is possible to reliably prevent the single crystal SiC substrate from being cracked.

The laminated structure includes a first carbon material supply plate disposed on one surface side of the single crystal SiC substrate and a second carbon material supply plate disposed on the other surface side of the single crystal SiC substrate. The structure which has may be sufficient.

  According to said structure, a single crystal SiC film can be grown on both surfaces of a single crystal SiC substrate.

Further, the laminated structure may be a structure in which Si plate is inserted between the single crystal SiC substrate and the carbon source supply plate.

  According to the above configuration, the Si melt layer can be easily brought into contact with the surface of the single crystal SiC substrate by melting part or all of the Si plate by heat treatment. Further, since the surface area of the Si melt exposed to the growth atmosphere can be reduced as compared with the case where the difference between the outer dimension of the laminated structure and the inner dimension of the first container is large as in Patent Documents 1 to 3, Si Thus, a single crystal SiC film having uniform crystals can be stably grown over a long period of time.

  In addition, the inner dimensions of the single crystal SiC substrate and the carbon raw material supply plate in the direction parallel to the in-plane direction when the stacked structure in the first container is accommodated, and the first container in the Si plate The difference between the outer dimension in the direction parallel to the direction of the inner dimension when housed is the difference between the inner dimension of the first container and the outer diameter of the single crystal SiC substrate and the carbon raw material supply plate. It may be within the same range as the above numerical range for.

  According to said structure, even if a part of Si board melt | dissolves and the lamination | stacking state of each member which comprises laminated structure becomes unstable, a single crystal SiC board | substrate, a carbon raw material supply board, and Si The movement of the plate in the in-plane direction can be restricted, and positional deviation between these members can be suppressed. Thereby, the uniformity of the single crystal SiC film produced | generated on a single crystal SiC substrate can further be improved.

  Further, a container made of carbon may be used as the first container. According to said structure, it can prevent that a container deform | transforms at the time of heat processing, or has a bad influence on the growth of a single crystal SiC film, and can grow a single crystal SiC film appropriately.

  As described above, the method for producing a single crystal SiC film of the present invention is a direction parallel to the in-plane direction of the single crystal SiC substrate and the carbon raw material supply plate when the laminated structure in the first container is accommodated. The difference between the inner dimension of the first crystal SiC substrate and the outer dimension in the direction parallel to the direction of the inner dimension when accommodated in the first container of the carbon raw material supply plate is 0.5 mm or more. 0.0 mm or less.

  Thereby, a single crystal SiC film can be grown on almost the entire surface of the single crystal SiC substrate without generating an ungrown region. Moreover, the said laminated structure can be easily accommodated in a 1st container. Moreover, it can suppress that a single crystal SiC substrate cracks by heat processing.

  An embodiment of the present invention will be described. FIG. 1 is an explanatory diagram for explaining a manufacturing process of a single crystal SiC film according to the present embodiment.

  As shown in this figure, in this embodiment, first, the carbon raw material supply plate 1a, the Si plate 2a, the spacer 3a, the single crystal SiC substrate 4, the Si substrate 2b, the spacer 3b, the carbon raw material supply plate 1b, and the weight 5 are placed below. The laminated structure laminated from the top to the top was accommodated in a container (first container) 6a, and the container 6a containing the laminated structure was accommodated in a sealed container (second container) 7 to seal the inside of the sealed container 7.

  The carbon raw material supply plate 1a is for supplying carbon to the surface (mainly the lower surface) of the single crystal SiC substrate 4 during heat treatment. In the present embodiment, a carbon raw material supply plate 1a is used in which the surface of a polycrystalline SiC substrate is polished into a mirror surface, and oils, oxide films, metals, etc. adhering to the surface are removed by washing or the like. However, the material of the carbon raw material supply plate 1a is not limited to this, and any material that can supply carbon to the surface of the single crystal SiC substrate 4 may be used. For example, a carbon substrate, a porous SiC substrate, a sintered SiC substrate, an amorphous SiC substrate, or the like may be used.

  The Si (silicon) plate 2a is for forming a Si melt layer on the surface (mainly the lower surface) of the single crystal SiC substrate 4 during heat treatment.

  The spacer 3a defines the distance between the single crystal SiC substrate 4 and the Si plate 2a, whereby the thickness of the Si melt layer (single crystal) formed between the single crystal SiC substrate 4 and the Si plate 2a during heat treatment. Thickness of the SiC substrate 11 and the carbon raw material supply plate 24 in the direction perpendicular to the substrate surface). As a result, the thickness of the single crystal SiC growth film (single crystal SiC epitaxial film) can be made uniform over the entire growth surface.

  As the single crystal SiC substrate 4, a conventionally known single crystal SiC substrate (for example, a commercially available single crystal SiC substrate) can be used. In the present embodiment, a 4H—SiC substrate having an off angle of 8 ° in the <11-20> direction was used. In the present embodiment, the surface of the single crystal SiC substrate 4 on which the single crystal SiC film is to be formed is planarized by a CMP method (chemical mechanical polishing method) before the single crystal SiC film is formed. Etc. were removed.

  The Si plate 2b is for forming a Si melt layer on the surface (mainly the upper surface) of the single crystal SiC substrate 4 during heat treatment.

  The spacer 3b defines the distance between the Si plate 2b and the carbon raw material supply plate 1b.

  The carbon raw material supply plate 1b is for supplying carbon to the surface (mainly the upper surface) of the single crystal SiC substrate 4 during heat treatment. As the carbon raw material supply plate 1b, the same material as the carbon raw material supply plate 1a can be used. In this embodiment, as the carbon raw material supply plate 1b, like the carbon raw material supply plate 1a, the surface of the polycrystalline SiC substrate is polished into a mirror surface, and oils, oxide films, metals, etc. adhering to the surface are removed by washing or the like. A thing was used.

  The weight 5 is applied to the Si raw material supply plate 1a, the Si plate 2a, the spacer 3a, the single crystal SiC substrate 4, the Si substrate 2b, the spacer 3b, and the carbon raw material supply plate 1b by applying an appropriate load. This is for controlling the distance between the crystalline SiC substrate 4 and the distance between the Si substrate 2b and the carbon raw material supply plate 1b to the thickness of the spacer. In the present embodiment, a block made of carbon is used as the weight 5. However, the material of the weight 5 is not limited to this, and any material may be used as long as the amount of deformation during heat treatment is negligible. For example, a refractory metal such as Ta may be used.

  The container (susceptor) 6a is formed by laminating a carbon raw material supply plate 1a, a Si plate 2a, a spacer 3a, a single crystal SiC substrate 4, a Si substrate 2b, a spacer 3b, a carbon raw material supply plate 1b, and a weight stone 5 from the bottom to the top. This is for accommodating the thing and suppressing the relative position in the horizontal direction between the single crystal SiC substrate 4 and the other material during the heat treatment. In the present embodiment, the container 6a is made of carbon. However, the material of the container 6a is not limited to this, and any material may be used as long as the deformation amount during the heat treatment is negligible. For example, a refractory metal such as Ta may be used. In the present embodiment, the container 6a having an open upper surface is used. However, the present invention is not limited to this, and a lid (not shown) for sealing the inside of the container 6a may be provided on the upper surface of the container 6a. Good.

  The sealed container 7 accommodates the container 6a and seals the inside of the sealed container 7, and grows a single crystal SiC film on the surface of the single crystal SiC plate 4 inside the sealed container 7 by Si evaporated during heat treatment. This is for maintaining the growth atmosphere. Specifically, the sealed container 7 includes a container body 7a and a lid 7b, and the inside can be sealed by closing the lid 7b. In the present embodiment, a carbon container is used as the sealed container 7. However, the material of the sealed container 7 is not limited to this, and a high melting point metal such as Ta may be used, for example. The shape and size of the sealed container 7 may be any shape and size that can maintain the inside of the container in the growth atmosphere of the single crystal SiC film during the heat treatment.

  In the present embodiment, the shape of the carbon raw material supply plate 1a, the Si plate 2a, the single crystal SiC substrate 4, the Si substrate 2b, the carbon raw material supply plate 1b, and the weight 5 as viewed from the normal direction of the substrate surface is 20 mm on a side. These materials were stacked so that the peripheral edge portions (end portions) in the in-plane direction were aligned in the vertical direction. Moreover, as the container 6a, a container whose opening has a square shape with a side of 21 mm was used.

  However, the shapes and dimensions of the carbon raw material supply plate 1a, the Si plate 2a, the single crystal SiC substrate 4, the Si substrate 2b, the carbon raw material supply plate 1b, and the weight 5 are not limited thereto. For example, a commercially available product may be used as the single crystal SiC substrate 4, and a single crystal SiC substrate 4 that matches the shape of the single crystal SiC substrate 4 may be used. The shape and dimensions of the container 6a are the same as the shape of the laminated structure of the carbon raw material supply plate 1a, the Si plate 2a, the single crystal SiC substrate 4, the Si substrate 2b, and the carbon raw material supply plate 1b (hereinafter referred to as growth material). Depending on the dimensions, it can be set as appropriate so that the stacked structure can be taken into and out of the container 6a and the positional deviation between the growth materials can be suppressed within an allowable range in a state where Si is dissolved during the heat treatment. . Specifically, the shape and dimensions of the container 6a are the direction parallel to the external dimension of the peripheral part (peripheral part viewed from the normal direction of the substrate surface) of the laminated structure (each growth material) and the direction of the external dimension. What is necessary is just to set so that the difference with the internal shape dimension of the container 6a may be 0.5 mm or more and 2.0 mm or less.

  In this embodiment, as the spacers 3a and 3b, a polycrystalline SiC plate is cut so that a cross section parallel to the substrate surface of the single crystal SiC substrate 4 becomes a square having a side of 5 mm, and the thickness (single crystal SiC substrate 4 was used which was mechanically polished so that the thickness of the substrate surface in the normal direction (4) was 30 μm ± 10 μm. The cross-sectional shapes and cross-sectional dimensions of the spacers 3a and 3b are not limited to this, and the interval between the single crystal SiC substrate 4 and the Si plate 2a and the interval between the Si substrate 2b and the carbon raw material supply plate 1b can be appropriately defined. Any shape and size may be used. Further, the thickness of the spacers 3a and 3b is not limited to the above thickness, and may be set as appropriate according to the desired thickness of the Si melt layer formed in the same layer as each of the spacers. However, in order to increase the growth rate of the single crystal SiC film, it is preferably 100 μm or less. Further, the material of the spacer 3a is not limited to polycrystalline SiC, and any material can be used as long as the amount of deformation during heat treatment is negligible. For example, a refractory metal such as Ta or carbon may be used.

  Next, a manufacturing process of the single crystal SiC film will be described. First, as described above, the carbon raw material supply plate 1a, the Si plate 2a, the spacer 3a, the single crystal SiC substrate 4, the Si substrate 2b, the spacer 3b, the carbon raw material supply plate 1b, and the weight 5 were laminated from the bottom to the top. The container was accommodated in a container (susceptor) 6a, and the container 6a was further accommodated in a sealed container 7 to seal the inside of the sealed container 7.

Next, after the inside of the sealed container 7 is depressurized to a pressure of 1 × 10 ⁻² Pa or less (after evacuation), this pressure state is maintained, and the temperature inside the sealed container 7 is not shown by heating means (not shown) The temperature was raised to a predetermined growth temperature (1800 ° C. in the present embodiment) at 20 ° C./min by a temperature controller capable of controlling the temperature raising rate and the temperature lowering rate. And after reaching a predetermined growth temperature, this temperature state was maintained for 30 minutes. After 30 minutes, the temperature in the sealed container 7 was lowered to 1420 ° C. at 20 ° C./min. Natural cooling was performed from 1420 ° C. to room temperature. As a result, a single crystal SiC film (4H—SiCSiC epitaxial film) of 20 μm to 30 μm could be formed on both surfaces of the single crystal SiC substrate 4.

  Next, the difference between the inner dimension of the container 6a and the outer diameter of the laminated structure of each growth material (each carbon raw material supply plate, each Si plate, and single crystal SiC substrate), and the positional deviation between the growth materials during the heat treatment The experimental result which investigated the relationship with the inhibitory effect of is demonstrated.

  FIG. 2 shows the difference between the inner shape dimension of the container 6a and the outer dimension of the laminated structure (the inner shape dimension of the container 6a and the measurement position of the inner shape dimension) by using a plurality of types of containers 6a having different inner shape dimensions. FIG. 6 is an explanatory diagram showing the results of examining the degree of positional deviation between growth materials and the growth state of a single-crystal SiC film when the difference between the outer dimensions of the growth materials at positions corresponding to 1) is changed. . The conditions are the same as those described above except that the shape and dimensions of the container 6a are different.

  As shown in this figure, when the difference between the inner shape dimension of the container 6a and the outer diameter dimension of the laminated structure (each growth material) is less than 0.5 mm, when the growth member is stored in the container 6a, It was difficult to insert. Further, when the above difference is less than 0.5 mm, the single crystal SiC substrate 4 is cracked during growth (during heat treatment).

  Further, when the above difference was 0.5 mm, it was possible to accommodate the growth member without any problem although it was a little difficult to insert when accommodating the growth member in the container 6a. Moreover, although the single crystal SiC substrate 4 rarely cracked during the heat treatment, the frequency of the crack generation was of a practically acceptable level. When the above difference is 0.5 mm, the positional deviation between the growth materials during the heat treatment can be suppressed to 0.5 mm or less, and the single crystal SiC film is formed on substantially the entire substrate surface of the single crystal SiC substrate 4. Was able to grow.

  Moreover, when said difference was 1.0 mm or more, when accommodating the growth member in the container 6a, it was able to insert easily. In particular, when the above difference was 2.0 mm or more, it could be inserted very easily. Further, when the difference was 1.0 mm or more, the single crystal SiC substrate 4 was not cracked during the heat treatment.

  When the above differences are 1.0 mm, 1.5 mm, and 2.0 mm, the positional deviations between the growth materials during the heat treatment are 0.7 ± 0.1 mm, 1.0 ± 0.2 mm, and 1.5 mm, respectively. The single crystal SiC film could be grown on substantially the entire substrate surface of the single crystal SiC substrate 4.

  Further, when the above difference was 2.5 mm, the positional deviation between the growth members became 2.0 mm or more, and some ungrown regions were generated on the single crystal SiC substrate 4.

  Further, when the above difference is 3.0 mm or more, the positional deviation between the growth members becomes 2.5 mm or more, and many ungrown regions are generated on the single crystal SiC substrate 4.

  From these experimental results, it is preferable to make the above difference 0.5 mm or more in order to easily store the laminated structure in the container 6a and not cause the single crystal SiC substrate 4 to crack. It turns out that it is more preferable to set it as 1.0 mm or more. In order to grow a single crystal SiC film over substantially the entire substrate surface of the single crystal SiC substrate 4 while suppressing misalignment between the growth members, it is preferable to set the above difference to 2.0 mm or less. Recognize.

  As described above, in the present embodiment, the laminated structure including the single crystal SiC substrate 4 and the carbon raw material supply plates 1a and 1b is accommodated in the container 6a having a shape corresponding to the laminated structure, and the container 6a is further sealed. A state in which the Si melt layer is brought into contact with the surface of the single crystal SiC substrate 4 (between the single crystal SiC substrate 4 and the carbon raw material supply plate 1a and the single crystal by performing heat treatment in the container 7) A method of manufacturing a single crystal SiC film, in which a single crystal SiC film is epitaxially grown on the single crystal SiC substrate 4 by performing heat treatment in a state in which an Si melt layer is interposed between the SiC substrate 4 and the carbon raw material supply plate 1b). The inner dimensions in the direction parallel to the in-plane direction of the single crystal SiC substrate 4 and the carbon raw material supply plates 1a and 1b when the laminated structure in the container 6a is accommodated, and the single crystal SiC substrate 4 and the carbon Charge supply plate 1a, a difference between the direction of the outside dimension parallel to the direction of the inner shape dimension when contained in a container 6a to 0.5mm or 2.0mm or less in 1b.

  Thereby, while accommodating the said laminated structure in the container 6a easily, suppressing the position shift of the growth members which comprise a laminated structure, suppressing that a single crystal SiC substrate cracks, a single crystal A single crystal SiC film can be grown on substantially the entire substrate surface of the SiC substrate.

  In other words, in the techniques of Patent Documents 1 to 3, since the distance between the container and each growth material is wide, when the Si plate melts during the heat treatment, the volume and mode of the Si plate change greatly. As a result of the unstable state and the large positional deviation between the growth members, a large number of ungrown regions of the single crystal SiC film were generated on the single crystal SiC substrate.

  On the other hand, in this embodiment, even if the above-mentioned difference is set to 2.0 mm or less, even if the Si plate is melted and the state in which the respective growth members are stacked becomes unstable, each growth member is caused by the container 6a. The movement in the in-plane direction (parallel direction of the substrate surface) can be regulated to suppress the positional deviation between the growth members. Thereby, a single crystal SiC film can be grown on almost the entire surface of the single crystal SiC substrate without generating an ungrown region.

  Moreover, it can suppress that a single crystal SiC substrate cracks by making said difference into 0.5 mm or more. In order to surely prevent the single crystal SiC substrate from being cracked, the above difference is preferably set to 1.0 mm or more.

  In this embodiment, the difference between the inner dimension of the container 6a and the outer diameter of each growth material (each carbon raw material supply plate, single crystal SiC substrate 4, each Si substrate) constituting the laminated structure is 0.5 mm. Although not less than 2.0 mm, the difference between at least the inner dimensions of the container 6a and the outer dimensions of the single crystal SiC substrate 4 and the carbon raw material supply plates 1a and 1b before heat treatment is not limited thereto. If the thickness is 0.5 mm or more and 2.0 mm or less, the positional deviation between the single crystal SiC substrate 4 and the carbon raw material supply plates 1a and 1b can be suppressed, and the single crystal SiC film can be grown on substantially the entire surface of the single crystal SiC substrate. it can. Moreover, it can prevent reliably that a crack arises in a single crystal SiC board | substrate by making said difference in the single crystal SiC board | substrate 4 into 1.0 mm or more.

  In addition, by making the difference between the inner dimensions of the container 6a and each growth material and the outer dimensions 0.5 mm or more and 2.0 mm or less, the molten Si stays in the container and the Si melt exposed to the growth atmosphere. Since the surface area of the liquid can be reduced, the evaporation amount of Si can be suppressed. Thereby, a single crystal SiC film having a uniform crystal can be stably grown.

  In the present embodiment, the configuration in which the single crystal SiC film is grown on both surfaces of the single crystal SiC substrate 4 has been described. However, the configuration is not limited to this, and the configuration in which the single crystal SiC film is grown only on one surface of the single crystal SiC substrate 4 is described. It is good. Further, the configuration of the laminated structure is not limited to the configuration shown in FIG. For example, when a single crystal SiC film is grown only on the lower surface side of the single crystal SiC substrate 4, both or one of the carbon raw material supply plate 1 b and the Si plate 2 b provided on the upper side of the single crystal SiC substrate 4 is omitted. May be. When the single crystal SiC film is grown only on the upper surface side of the single crystal SiC substrate 4, both or one of the carbon raw material supply plate 1a and the Si plate 2a provided on the lower side of the single crystal SiC substrate 4 is omitted. May be. When a single crystal SiC film is grown only on one surface of single crystal SiC substrate 4, the surface to be grown may be the upper surface side or the lower surface side.

  Further, the order of stacking the growth materials (the carbon raw material supply plate 1a, the Si plate 2a, the single crystal SiC substrate 4, the Si substrate 2b, the carbon raw material supply plate 1b) and the spacers 3a and 3b is not limited to the above example. Any structure may be used as long as the Si melt is interposed between the surface of the single crystal SiC substrate 4 on which the single crystal SiC film is grown during the heat treatment and the member facing it.

  In this embodiment, the spacer 3a is disposed between the Si plate 2a and the single crystal SiC substrate 4, and the spacer 3b is disposed between the Si plate 2b and the carbon raw material supply plate 1b. The arrangement of 3b is not limited to this. For example, the spacer 3a may be disposed between the carbon raw material supply plate 1a and the Si plate 2a. The spacer 3b may be disposed between the single crystal SiC substrate 4 and the Si plate 2b. One or both of the spacers 3a and 3b may be omitted.

  In the present embodiment, the Si plates 2a and 2b are disposed between the single crystal SiC substrate 4 and the carbon raw material supply plate 1a and between the single crystal SiC substrate 4 and the carbon raw material supply plate 1b. However, the present invention is not limited to this, and any structure may be used as long as Si can be supplied to the generation surface of the single crystal Si film in the single crystal SiC substrate 4 during heat treatment.

  Si plates 2a and 2b may be Si films formed on carbon raw material supply plates 1a and 1b, for example. Note that the term “plate” in this specification includes a film-like member.

  In this embodiment, the time for maintaining the growth temperature is 30 minutes. However, the time is not limited to this, and may be set as appropriate according to the required film thickness of the single crystal SiC film. In addition, it was confirmed by experiments that a single crystal SiC film having a uniform crystal can be stably formed within a holding time range of 10 minutes to 60 minutes.

  The predetermined growth temperature is not particularly limited as long as it is 1420 ° C. or higher, which is the melting point of Si, but 1500 ° C. or higher and 2300 ° C. or lower in order to grow the SiC epitaxial film efficiently and stably. It is preferable to be within the range.

Moreover, in this embodiment, the inside of the airtight container 7 was pressure-reduced to the pressure of 1 * 10 ^<-2 > Pa or less before heat processing. Thereby, the atmospheric component in the airtight container 7 can be discharged | emitted out of a container, and it can be made a clean atmosphere. In the present embodiment, the heat treatment is performed in a vacuum (1 × 10 ⁻² Pa or less) atmosphere. However, the present invention is not limited to this, and for example, the inside of the sealed container 7 is reduced to a pressure of 1 × 10 ⁻² Pa or less. After that, in order to suppress the evaporation of Si, an inert gas such as Ar may be introduced into the container and then heat treatment may be performed in an inert gas atmosphere at atmospheric pressure or lower.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  According to the present invention, a laminated structure including a single crystal SiC substrate and a carbon raw material supply plate is housed in a sealed container, and heat treatment is performed in a state where the Si melt layer is in contact with the surface of the single crystal SiC substrate. The present invention can be applied to a method for manufacturing a single crystal SiC film in which a single crystal SiC film is epitaxially grown on the single crystal SiC substrate. Since the single crystal SiC film produced by the production method of the present invention has few crystal defects and high uniformity, it can be suitably used for light emitting diodes, various semiconductor diodes, various electronic devices, and the like.

It is explanatory drawing for demonstrating the manufacturing process of the single crystal SiC film concerning one Embodiment of this invention. In the manufacturing process of the single crystal SiC film according to one embodiment of the present invention, the degree of positional deviation between the growth materials when the difference between the inner shape dimension of the container and the outer dimension of the growth material is changed, and the single crystal It is explanatory drawing which shows the experimental result which investigated the growth condition of the SiC film.

Explanation of symbols

1a, 1b Carbon raw material supply plate 2a, 2b Si plate 3a, 3b Spacer 4 Single crystal SiC substrate 5 Weight stone 6a Container 7 Sealed container 7a Container body 7b Lid

Claims (6)

A laminated structure including at least a single crystal SiC substrate and a carbon raw material supply plate is accommodated in a first container, the first container is accommodated in a second container capable of sealing the inside, and the single crystal SiC A method for producing a single crystal SiC film, wherein a single crystal SiC film is epitaxially grown on the single crystal SiC substrate by performing a heat treatment in a state where the Si melt layer is in contact with the surface of the substrate,
An inner dimension in a direction parallel to the in-plane direction of the single crystal SiC substrate and the carbon raw material supply plate when the laminated structure in the first container is accommodated, and the single crystal SiC substrate and the carbon raw material supply plate A method for producing a single crystal SiC film, characterized in that a difference from an outer dimension in a direction parallel to the direction of the inner dimension when accommodated in the first container is 0.5 mm or more and 2.0 mm or less. .   The method for producing a single crystal SiC film according to claim 1, wherein the difference is 1.0 mm or more and 2.0 mm or less. The stacked structure includes a first carbon material supply plate disposed on one surface side of the single crystal SiC substrate and a second carbon material supply plate disposed on the other surface side of the single crystal SiC substrate. The method for producing a single crystal SiC film according to claim 1 or 2. The laminated structure is a single crystal according to any one of claims 1 to 3, wherein the Si plate is inserted structure between the single crystal SiC substrate and the carbon source supply plate A method for producing a SiC film.   When the laminated structure in the first container is accommodated, the inner dimensions of the single crystal SiC substrate and the carbon raw material supply plate in a direction parallel to the in-plane direction, and the first container in the Si plate are accommodated in the first container. Sometimes the difference between the outer dimension in the direction parallel to the direction of the inner dimension is the difference between the inner dimension of the first container and the outer diameter of the single crystal SiC substrate and the carbon raw material supply plate. 5. The method for producing a single crystal SiC film according to claim 4, wherein the value is in the same range as the numerical value range.   6. The method for producing a single crystal SiC film according to claim 1, wherein a container made of carbon is used as the first container.

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