JP5936344B2 - SiC crystal growth method and SiC crystal manufacturing apparatus - Google Patents

Description

  In this specification, the technique regarding the growth method of a silicon carbide (SiC) crystal | crystallization is disclosed.

  One method for growing SiC crystals is a liquid phase growth method. In the liquid phase growth method, for example, an SiC crystal is epitaxially grown on a seed crystal substrate by bringing the seed crystal substrate into contact with a solution containing carbon by melting silicon. It has been proposed to use a sapphire substrate as the seed crystal substrate. Since the sapphire substrate is less expensive than the SiC single crystal substrate, if the sapphire substrate can be used as the seed crystal substrate, the manufacturing cost of the SiC crystal substrate can be reduced.

JP 2008-1000089 A

  The solution in which silicon is melted needs to be maintained at a temperature equal to or higher than the melting point of silicon in order to maintain a liquid phase state. However, at a temperature higher than the melting point of silicon, the sapphire substrate is dissolved in a solution in which silicon is melted. Then, it is necessary to strictly adjust various parameters such as the solution temperature and the thickness of the sapphire substrate so that the sapphire substrate that is the seed crystal substrate does not disappear, so it is difficult to grow the SiC crystal. .

  In this specification, the growth method of a SiC crystal is indicated. This growth method includes a step of realizing a state in which a sapphire substrate is in contact with a solution obtained by heating silicon and metal below the melting point of silicon through a film containing carbon. Moreover, a part of film | membrane containing carbon lose | disappears, and the process which maintains a state until it reaches a direct contact with a sapphire substrate and a solution in the disappearance part is provided. In addition, the method includes a step of cooling the solution after a part of the carbon-containing film disappears.

  In the above method, a solution containing silicon heated to a melting point of silicon or lower can be used. In addition, in the disappearance portion of the film containing carbon, a state in which the sapphire substrate and the solution containing silicon are in direct contact can be formed. Since the solution and the sapphire substrate are in contact with each other through a film containing carbon, the film containing carbon can be used as a carbon supply source. As described above, it is possible to grow the SiC crystal on the sapphire substrate at a lower temperature than in the case of using a solution in which silicon is melted. Therefore, a situation where the sapphire substrate is dissolved in the solution can be prevented. In addition, since the portion where the sapphire substrate and molten silicon are in direct contact can be used as the starting point of SiC crystal growth, the SiC crystal is epitaxially grown so that it is aligned with the crystal surface of the underlying sapphire substrate by cooling the solution. Can be made.

  In the above crystal growth method, the metal is a metal having a melting point lower than that of silicon, the solution is a solution obtained by melting the metal, the silicon substrate is in contact with the solution, and sapphire is passed through a film containing carbon in the solution. You may provide the process of implement | achieving the state which a board | substrate contacts. By using a metal having a melting point lower than that of silicon, the metal can be maintained in a liquid phase at a temperature lower than the melting point of silicon. In addition, since the molten metal and the silicon substrate are in contact with each other, silicon is eluted from the silicon substrate to the molten metal, and the molten metal can be in a state where silicon is contained. As described above, it is possible to grow the SiC crystal on the sapphire substrate at a lower temperature than in the case of using a solution in which silicon is melted. Therefore, a situation where the sapphire substrate is dissolved in the solution can be prevented.

  In the above crystal growth method, a metal plate and a silicon substrate are stacked on a sapphire substrate on which a carbon-containing film is formed on at least one surface, and the sapphire substrate, the carbon-containing film, the metal plate, and the silicon substrate are sequentially stacked. A step of preparing a laminated structure that has been prepared, and the laminated structure may be heated to a temperature not lower than the melting point of the metal and not higher than the melting point of silicon to generate a solution. As a result, it is possible to easily create a state in which the silicon substrate is in contact with the solution and the sapphire substrate is in contact with the solution through the film containing carbon.

  The crystal growth method preferably includes a step of heating to a temperature higher than the melting point of a metal having a lower melting point than silicon and lower than the sublimation temperature of the sapphire substrate. Thereby, the situation where a sapphire substrate is damaged by the molten metal and the situation where the sapphire substrate is dissolved in the molten metal can be effectively prevented.

  In the above crystal growth method, silicon and metal are supplied by an alloy of silicon and metal, the alloy has a lower melting point than silicon, and the solution is heated by heating the alloy to a temperature above the melting point of the alloy. May be obtained. As a result, it is possible to grow a SiC crystal on the sapphire substrate at a lower temperature than when using a solution in which silicon is melted. Therefore, a situation where the sapphire substrate is dissolved in the solution can be prevented.

In the above crystal growth method, the metal preferably contains aluminum. Since aluminum is a constituent component of the sapphire substrate (Al ₂ O ₃ ), the aluminum is contained in the solution, so that the sapphire substrate can be hardly dissolved in the solution. Also, since the melting point of aluminum is about 660 ° C., the temperature of the molten metal can be lowered below the melting point of silicon (about 1410 ° C.).

In the above crystal growth method, preferably it includes a step of forming a film containing microcrystals of carbon as a film containing carbon on the surface of the sapphire substrate. Thereby, the effect which protects a sapphire substrate from molten silicon can be heightened more.

  In the crystal growth method described above, it is preferable to form a film containing carbon microcrystals on the surface of the sapphire substrate by physical vapor deposition (PVD). This makes it possible to efficiently form a film containing microcrystals of carbon.

  In the above crystal growth method, it is preferable to form a film containing carbon having a thickness of 10 nanometers or more on the surface of the sapphire substrate. Thereby, a sapphire substrate can be effectively protected from molten silicon.

  In the above crystal growth method, it is preferable to form a film containing carbon on the {0001} plane of the sapphire substrate.

  In the crystal growth method described above, a sapphire substrate on which a film containing carbon is formed on at least one surface may be immersed in a solution obtained by heating silicon and metal below the melting point of silicon. Also by this, it is possible to realize a state in which the sapphire substrate is in contact with the metal melted in the solution through the film containing carbon.

  The crystal substrate includes a first layer containing a sapphire crystal, an amorphous structure, a second layer covering a part of the surface of the first layer, an SiC crystal, A third layer covering the surface of the first layer and covering the surface of the first layer exposed from the second layer.

  In the above crystal substrate, the second layer may contain carbon. The surface of the first layer may be a {0001} plane of sapphire crystal. The surface of the third layer may be a {100} plane of SiC crystal.

  According to the technique disclosed in this specification, a method of heteroepitaxially growing a SiC crystal on a sapphire substrate can be provided.

1 is a schematic diagram of a SiC crystal manufacturing apparatus of Example 1. FIG. It is a flowchart of the growth method of a SiC crystal. It is a figure which shows a lamination state. It is a cross-sectional enlarged photograph. It is a schematic diagram of the growth process of a SiC crystal. It is a schematic diagram of the growth process of a SiC crystal. It is a schematic diagram of the growth process of a SiC crystal. It is a schematic diagram of the growth process of a SiC crystal. 3 is a schematic diagram of a SiC crystal manufacturing apparatus of Example 2. FIG. It is a binary phase diagram of Au-Si.

Example 1
Example 1 of the present application will be described with reference to the drawings. FIG. 1 shows a SiC crystal manufacturing apparatus (hereinafter abbreviated as a crystal manufacturing apparatus) 1 according to a first embodiment. The crystal manufacturing apparatus 1 includes a crucible 10. The crucible 10 is made of a material containing carbon. Examples of the material of the crucible 10 include graphite and SiC. The crucible 10 is disposed on the crucible base 11. The crucible base 11 can be rotated. The crucible 10 can be sealed with a crucible lid 14. The outer periphery of the crucible 10 is covered with a heat insulating material 12 for heat insulation. A normal coil 13 having a multiple spiral structure is disposed on the outer periphery of the heat insulating material 12. The normal conducting coil 13 is a device for induction heating the crucible 10. A high-frequency power source (not shown) is connected to the normal conducting coil 13. The crucible 10, the heat insulating material 12, and the normal conductive coil 13 are disposed inside the chamber 15. The chamber 15 includes an intake port 16 and an exhaust port 17.

  A sapphire substrate 20 is placed on the bottom of the crucible 10. A carbon film 21 is formed on the surface of the mounted sapphire substrate 20. A metal solution 25 is held in the crucible 10. The metal solution 25 is a solution whose main component is a melt obtained by melting a metal. The metal used for the metal solution 25 may be any metal as long as it can dissolve silicon and has a lower melting point than that of silicon. For example, Al, Pb, Ag, Cu, or Sn may be used. In Example 1, the case where aluminum (Al) is used as the metal used in the metal solution 25 will be described.

  In addition, a silicon substrate 23 is disposed above the sapphire substrate 20 so as to be spaced from the surface of the sapphire substrate 20. And the state in which the surface of the sapphire substrate 20 and at least a part of the silicon substrate 23 are immersed in the metal solution 25 is formed. This state is a state for growing a SiC crystal on a sapphire substrate, which will be described later.

  A SiC crystal growth method according to Example 1 will be described with reference to the flow of FIG. In step S1, a step of forming a carbon film 21 containing carbon microcrystals on the surface of the sapphire substrate 20 is performed. Specifically, a sapphire substrate 20 having a plane orientation of {0001} is prepared. Then, a carbon film 21 containing carbon microcrystals is formed on the {0001} plane of the sapphire substrate by PVD (physical vapor deposition).

  By forming the carbon film 21 by the PVD method, the carbon film 21 can contain carbon microcrystals. The carbon film 21 containing carbon microcrystals has a higher film strength than an amorphous (amorphous) carbon film. Therefore, the sapphire substrate 20 can be more effectively protected from the metal solution 25 in the process described later. The film thickness of the carbon film 21 is preferably 10 nanometers or more. It has been experimentally revealed that the sapphire substrate 20 can be effectively protected from the metal solution 25 in a process described later with a film thickness of 10 nanometers or more. Further, it has been experimentally shown that even if the film thickness of the carbon film 21 is about 10 micrometers, the SiC crystal can be heteroepitaxially grown on the sapphire substrate 20.

  Specific examples of the PVD method include a sputtering method and an ion plating method. In these methods, the target graphite is exposed to an ion beam, arc discharge, glow discharge, or the like in a vacuum, and scattered carbon atoms are attached to the surface of the sapphire substrate. In addition, since the more specific film-forming method by PVD method is a known technique, detailed description is abbreviate | omitted here.

  In step S1, it is preferable to form the carbon film 21 on the side surface and the back surface in addition to the surface of the sapphire substrate 20 (surface on which the SiC crystal is grown). Thereby, the sapphire substrate 20 can be more effectively protected from the metal solution 25.

  Next, in step S <b> 2, as shown in FIG. 3, the sapphire substrate 20, the aluminum thin plate 24, and the silicon substrate 23 are placed over the bottom of the crucible 10. Thereby, the lamination | stacking state by which the sapphire substrate 20, the carbon film 21, the aluminum thin plate 24, and the silicon substrate 23 are laminated | stacked in order from the downward direction can be formed. In addition, the weight of the silicon substrate 23 should just be sufficient weight to supply the silicon | silicone used as the raw material of the SiC crystal produced | generated by step S4 mentioned later.

  In step S3, the aluminum thin plate 24 is melted to produce a metal solution 25. Specifically, in step S2, the crucible 10 in which the sapphire substrate 20, the aluminum thin plate 24, and the silicon substrate 23 are set is placed on the crucible base 11 of the crystal manufacturing apparatus 1. And the crucible 10 is induction-heated by sending the alternating current of a predetermined frequency to the normal conduction coil 13. FIG. In addition, an inert gas is supplied into the chamber 15 from the air inlet 16 and the crucible base 11 is rotated at a predetermined rotational speed. The heating temperature is set in the range of not less than the melting point (660 ° C.) of the aluminum thin plate 24 and not more than the melting point of silicon (1410 ° C.). Thereby, the aluminum thin plate 24 melt | dissolves and the metal solution 25 is produced | generated. Then, as shown in the schematic diagram of FIG. 5, a state where the metal solution 25 and the silicon substrate 23 are in contact with each other is created, so that silicon can be dissolved in the metal solution 25. In addition, since the metal solution 25 and the sapphire substrate 20 are brought into contact with each other via the carbon film 21 formed on the surface of the sapphire substrate, an SiC crystal is grown on the sapphire substrate 20 in step S4 described later. Can be made.

  The heating temperature is more preferably lower than the sublimation temperature (about 1300 ° C.) of the sapphire substrate 20. As a result, the situation in which the sapphire substrate is damaged (the surface roughness of the sapphire substrate increases, a part of the sapphire substrate disappears, etc.) and the situation in which the sapphire substrate is dissolved in the metal solution 25, Further, it can be effectively prevented.

  In Example 1, the heating temperature of the metal solution 25 was 1200 ° C., argon gas was supplied into the chamber 15, and the pressure in the chamber 15 was atmospheric pressure. In addition, these conditions used in Example 1 are examples, and other conditions can also be used.

  In step S <b> 3, the carbon film 21 is dissolved in the metal solution 25 while the temperature of the metal solution 25 is maintained at 1200 ° C. When the carbon film 21 is melted, the entire surface of the carbon film 21 is not melted at the same speed, but is melted unevenly. Then, by appropriately controlling various parameters relating to the dissolution rate of the carbon film 21 (the film thickness of the carbon film 21, the time for maintaining the metal solution 25 at 1200 ° C., the temperature of the metal solution 25, etc.), the carbon film 21 A part of the surface of the sapphire substrate 20 disappears in some places, and a shape in which the surface of the sapphire substrate 20 is exposed at the disappeared portion can be created (see the schematic diagram of FIG. 6). Thereby, the metal solution 25 comes into direct contact with the sapphire substrate 20 at the disappearance portion of the carbon film 21. Further, the carbon film 21 remaining on the surface of the sapphire substrate 20 is damaged by the metal solution 25, so that at least a part thereof is in an amorphous state. The carbon film 21 in the amorphous state is considered to contain Si, Al and the like.

  In step S <b> 4, an SiC crystal is grown on the surface of the sapphire substrate 20. Specifically, a cooling process is performed in which the entire surface of the sapphire substrate 20 and at least a part of the silicon substrate 23 are gradually cooled while maintaining the state in which the surface is immersed in the metal solution 25. The growth mechanism of the SiC crystal in step S4 will be described. In the cooling step of step S4, heat is released from the surface of the crucible 10. The sapphire substrate 20 is in contact with the crucible 10. Then, since the metal solution 25 existing in the vicinity of the surface of the sapphire substrate 20 has a slightly higher cooling rate than the metal solution 25 present in other places, the metal solution in a portion in contact with the surface of the sapphire substrate 20. 25 is made lower in temperature than the metal solution 25 in other parts. Therefore, since silicon and carbon in the metal solution 25 in the vicinity of the surface of the sapphire substrate 20 are supersaturated, the SiC crystal is epitaxially grown on the sapphire substrate 20. Further, since the portion where the surface of the sapphire substrate 20 is exposed serves as a starting point for the growth of the SiC crystal, the heteroepitaxial growth of the SiC crystal is performed so as to align with the crystal surface of the underlying sapphire substrate 20. Thereby, as shown in the schematic diagram of FIG. 7, the SiC crystal 26 grows so as to fill the disappearing portion of the carbon film 21.

  After the SiC crystal grows so as to fill the disappearing part of the carbon film 21, if the state in which the sapphire substrate 20 is further immersed in the metal solution 25 is further maintained, the SiC crystal filling the disappearing part of the carbon film 21 is maintained. An SiC crystal can be epitaxially grown on the surface or the surface of the remaining carbon film 21. At this time, the SiC crystal can be grown on the surface of the remaining carbon film 21 so as to be aligned with the crystal plane of the SiC crystal filling the disappearing portion of the carbon film 21. Thereby, as shown in the schematic diagram of FIG. 8, the SiC crystal 26 is grown so as to cover the surface of the carbon film 21 and to cover the surface of the sapphire substrate 20 exposed at the disappeared portion of the carbon film 21. Can do. Even after the carbon film 21 is covered with the SiC crystal, carbon can be supplied into the metal solution 25 by melting the crucible 10, so that the SiC crystal can be grown.

  In FIG. 4, the cross-sectional enlarged photograph of the interface of the SiC crystal obtained in Example 1 and a sapphire substrate is shown. In the photograph of FIG. 4, the SiC crystal is surrounded by a frame line for easy viewing. As shown in FIG. 4, it can be seen that SiC crystals are grown on the surface of the sapphire substrate.

<Effect>
The effect of the manufacturing method of the SiC crystal according to Example 1 will be described. When a SiC crystal is grown by a liquid phase growth method using a solution in which silicon is melted, the temperature of the solution is set to a temperature equal to or higher than the melting point of silicon (about 1410 ° C.) in order to maintain the liquid phase state of the solution. Need to be maintained. However, when a solution having a temperature equal to or higher than the melting point of silicon is used, the reaction between the sapphire substrate and the solution is more activated, so that the sapphire substrate is dissolved in the solution. If the sapphire substrate is dissolved in the solution, the seed crystal substrate disappears, so that the SiC crystal cannot be grown.

  On the other hand, in the method for producing an SiC crystal according to Example 1, the metal solution 25 obtained by melting aluminum having a melting point equal to or lower than the melting point of silicon (melting point: about 660 ° C.) is used for the liquid phase growth method. The liquid phase state of the metal solution 25 can be maintained at a temperature equal to or lower than the melting point. This makes it possible to perform the liquid phase growth method at a lower temperature than when using a solution in which silicon is melted. Therefore, since the reaction between the sapphire substrate and the solution can be further suppressed, a situation where the sapphire substrate is dissolved in the solution can be prevented.

Also, aluminum has been used to produce a metal solution 25 is a component of sapphire substrate (Al 2 _{O 3).} Therefore, when the metal solution 25 contains aluminum, the sapphire substrate 20 can be hardly dissolved in the metal solution 25.

  In the technique of the present application, since the metal solution 25 and the silicon substrate 23 are in contact with each other, silicon is eluted from the silicon substrate 23 to the metal solution 25 and silicon is contained in the metal solution 25. be able to. Moreover, since the metal solution 25 and the sapphire substrate 20 are in contact with each other via the carbon film 21, the carbon film 21 can be used as a carbon supply source. Thereby, it is possible to heteroepitaxially grow the SiC crystal on the sapphire substrate 20.

  In the technique of the present application, the surface of the sapphire substrate 20 is protected by the carbon film 21 remaining on the surface of the sapphire substrate 20, and the portion where the surface of the sapphire substrate 20 is exposed due to the disappearance of the carbon film 21 is a starting point. As described above, a SiC crystal can be grown. That is, by bringing only a part of the sapphire substrate 20 into contact with the silicon solution 22, it is possible to grow the SiC crystal so as to align with the crystal surface of the sapphire substrate 20 while preventing the sapphire substrate 20 from dissolving. Therefore, it is possible to epitaxially grow a SiC crystal on the sapphire substrate 20.

  Since the sapphire substrate is less expensive than the SiC crystal substrate, the production cost of the SiC crystal substrate can be further reduced by using the sapphire substrate as the seed crystal substrate. Further, the lattice constant mismatch between sapphire and SiC is smaller than the lattice constant mismatch between silicon and SiC. Therefore, the number of defects caused in the grown SiC crystal due to lattice mismatch is reduced when the sapphire substrate is used as the seed crystal substrate, compared to when the silicon crystal is used as the seed crystal substrate. be able to.

  In addition, the SiC crystal manufacturing method according to the first embodiment includes a step of forming a carbon film containing carbon microcrystals on the surface of the sapphire substrate. Since the carbon film containing carbon microcrystals has higher film strength than the amorphous (amorphous) state carbon film, the sapphire substrate can be more effectively protected from the silicon solution.

(Example 2)
FIG. 9 shows a crystal manufacturing apparatus 1a according to the second embodiment. A metal solution 25 is held in the crucible 10. A silicon substrate 23 is placed on the bottom of the crucible 10. A holding jig 18 is provided above the crucible 10. A sapphire substrate 20 is attached to the tip of the holding jig 18 so that the surface on which the carbon film 21 is formed faces the crucible 10. The holding jig 18 can be moved up and down. The holding jig 18 is made of graphite. In addition, since the other structure of the crystal manufacturing apparatus 1a is the same as that of the crystal manufacturing apparatus 1 (FIG. 1) which concerns on Example 1, description is abbreviate | omitted here.

  A method for growing a SiC crystal according to Example 2 will be described. Note that a description of the same parts as those of the SiC crystal growth method according to the first embodiment will be omitted. First, a step of forming a carbon film 21 containing carbon microcrystals on the surface of the sapphire substrate 20 is performed. The sapphire substrate 20 on which the carbon film 21 is formed is fixed to the tip of the holding jig 18 so that the surface on which the carbon film 21 is formed faces the crucible 10. Next, the silicon substrate 23 and the aluminum thin plate are placed in the crucible 10, and heated to a temperature not lower than the melting point of the aluminum thin plate and not higher than the melting point of silicon, thereby generating the metal solution 25. Then, the holding jig 18 is lowered from above the crucible 10 into the crucible 10, and the sapphire substrate 20 is immersed in the metal solution 25. Thereby, a state in which the metal solution 25 and the sapphire substrate 20 are in contact via the carbon film 21 is created. If a shape in which a part of the carbon film 21 disappears at some places on the surface of the sapphire substrate 20 and the surface of the sapphire substrate 20 is exposed at the disappeared portion is created, the process proceeds to the cooling step. The immersion state is maintained until the SiC crystal is epitaxially grown so as to cover the surface of the carbon film 21 and to cover the surface of the sapphire substrate 20 exposed at the disappeared portion of the carbon film 21. After the SiC crystal is completed, the holding jig 18 is pulled upward to complete the SiC crystal manufacturing process.

(Example 3)
The crystal manufacturing method according to Example 3 is a form in which a silicon alloy solution 25a is used instead of the metal solution 25. In the third embodiment, the sapphire substrate 20 and the silicon alloy are placed in the crucible 10 in step S2. A silicon alloy is an alloy of Si and another metal. In step S3, the silicon alloy is melted to produce a silicon alloy solution 25a. The heating temperature is set in the range of the melting point of the silicon alloy to the melting point of the silicon. In step S4, a SiC crystal is grown on the surface of the sapphire substrate 20 using the silicon alloy solution 25a. Since other configurations are the same as those of the crystal manufacturing method according to the first embodiment, detailed description thereof is omitted here.

  The effect of Example 3 will be described. As an example, FIG. 10 shows a binary phase diagram of Au—Si. As can be seen from FIG. 10, Au alone or Si alone does not dissolve unless it is 1000 ° C. or higher. However, it can be seen that by melting Si and Au, the melting point can be lowered to about 400 ° C. when Si is about 30 (atom%). Thus, the melting point of most metals can be lowered by alloying with Si. Therefore, it is possible to grow a SiC crystal on the sapphire substrate using the silicon alloy solution 25a having a lower temperature than a solution in which silicon is melted or a solution in which a single metal is melted. Therefore, a situation where the sapphire substrate is dissolved in the solution can be prevented.

  In addition, the metal used for a silicon alloy should just be a metal which can reduce melting | fusing point by alloying with Si. Specifically, any metal may be used as long as it has a state diagram as shown in FIG. Examples of such metals include Ag, Al, Au, Ca, Co, Cr, Mn, Ni, Sn, Ti, and Zn.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  In Example 3, an alloy generated by Si and two or more metals may be used.

  In this embodiment, the silicon supply source in the metal solution 25 is not limited to the silicon substrate. The silicon supply source may be a substance containing silicon, and for example, a SiC substrate may be used.

  In step S1, the step of forming a carbon film containing carbon microcrystals is not limited to the PVD method, and may be formed using, for example, a CVD method.

  In step S <b> 1, the carbon film 21 may be formed on a part of the surface of the sapphire substrate 20 to form a shape in which portions of the surface of the sapphire substrate 20 are exposed. Thereby, in step S3, it is possible to omit the step of eliminating a part of the carbon film 21 by dissolution.

  In the cooling process of step S4, means for bringing the silicon solution 22 near the surface of the sapphire substrate 20 into a supersaturated state is not particularly limited. Any means generally available in the liquid phase growth method can be adopted, and for example, a cooling device may be used.

  In Examples 1 and 2, the solution used for the solvent of Si or C is not limited to a solution in which a metal is melted.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

  1: crystal production apparatus, 10: crucible, 13: normal coil, 20: sapphire substrate, 21: carbon film, 23: silicon substrate, 24: aluminum thin plate, 25: metal solution

Claims (12)

A method for growing a SiC crystal comprising:
Realizing a state in which the sapphire substrate is in contact with a solution obtained by heating silicon and metal below the melting point of silicon through a film containing carbon;
Some of the film is lost, including the carbon, a step to sustain the state up to the sapphire substrate solution is in direct contact with the disappearance unit,
After a part of the film containing the carbon is lost, a step of cooling the solution,
A method for growing a SiC crystal, comprising: The metal is a metal having a lower melting point than silicon;
The solution is a solution obtained by melting the metal,
Wherein with the silicon substrate is in contact with the solution, the crystal growth method according to claim 1, characterized in that it comprises the step of realizing a state where the sapphire substrate contact via the film containing the carbon to the solution. Overlapping the plate and the silicon substrate of the metal sapphire substrate film containing the carbon is deposited on at least one side, the plate and the silicon substrate layer and the metal containing the carbon and sapphire substrate are laminated in this order A process for preparing a laminated structure,
As a stacked structure by heating to a temperature below the melting point of silicon in the metal above the melting point to generate the solution, together with the silicon substrate is in contact with said solution, a sapphire substrate through a membrane comprising said carbon in said solution 3. The crystal growth method according to claim 2, wherein a contact state is realized.   4. The crystal growth method according to claim 1, further comprising a step of heating to a temperature higher than a melting point of the metal and lower than a sublimation temperature of the sapphire substrate. The silicon and metal are supplied by an alloy of silicon and metal,
The alloy has a lower melting point than silicon;
2. The crystal growth method according to claim 1, wherein the solution is obtained by heating the alloy to a temperature not lower than the melting point of the alloy.   The crystal growth method according to claim 1, wherein the metal contains aluminum. The crystal growth method according to claim 1, further comprising a step of forming a film containing microcrystals of carbon on the surface of the sapphire substrate as the film containing carbon. 8. The crystal growth method according to claim 7, wherein a film containing the carbon microcrystals is formed on the surface of the sapphire substrate by physical vapor deposition (PVD). The crystal growth method according to claim 1, wherein a film containing carbon having a thickness of 10 nanometers or more is formed on a surface of a sapphire substrate. The crystal growth method according to claim 1, wherein the film containing carbon is formed on a {0001} plane of a sapphire substrate. Silicon and metal to the solution obtained was heated to below the melting point of silicon, was immersed sapphire substrate film containing the carbon is deposited on at least one side, through a film containing the carbon to the solution 2. The crystal growth method according to claim 1, wherein a state in which the sapphire substrate is in contact is realized. A SiC crystal manufacturing apparatus,
Means for realizing a state in which a sapphire substrate is in contact with a solution obtained by heating silicon and metal below the melting point of silicon through a film containing carbon;
Some of the film is lost, including the carbon, means for sustaining the state up to the sapphire substrate solution is in direct contact with the disappearance unit,
After a part of the film containing the carbon is lost, a means for cooling the said solution,
An SiC crystal manufacturing apparatus comprising: