JP4350484B2 - Method for producing aluminum nitride single crystal - Google Patents

Description

The present invention is used as a dispersion material (filler) for improving mechanical strength and heat dissipation, or as a substrate material, heat dissipation material, or structural material for electronic / electrical parts, particularly semiconductor laser elements and light emitting diodes. The present invention relates to a method for manufacturing a single crystal of aluminum nitride (AlN) that is promising as a substrate material, a heat radiating material, or a structural material for electronic / electrical parts that generate a large amount of heat.

In devices and apparatuses that use components that generate a large amount of heat, such as electronic / electrical components, optical device components, or OA device components, it is required to quickly dissipate the generated heat. Therefore, conventionally, as a substrate material or a heat dissipation material (heat sink) that comes into contact with these components, or a component material of these components (hereinafter referred to as “substrate material”), the thermal conductivity is high and the heat dissipation is excellent. Metal materials (eg, aluminum (Al), copper (Cu), etc.) have been used.

However, in recent years, devices and apparatuses in which these components are used tend to be reduced in size, increased in density, and increased in output, and the level of heat dissipation required for substrate materials and the like has become higher. In addition, characteristics that cannot be sufficiently imparted by metal materials such as mechanical strength and electrical insulation may be required. Under such circumstances, aluminum nitride, which is excellent in various properties such as mechanical strength, heat resistance, corrosion resistance, and electrical insulation in addition to heat dissipation, is being used as a substrate material.

In general, aluminum nitride is used as a constituent material for a substrate material such as aluminum nitride, but recently, an aluminum nitride single crystal (bulk single crystal) that may be capable of forming a higher performance substrate material or the like. (Or whiskers) are attracting attention. The bulk single crystal is used as a substrate material utilizing the heat dissipation property as well as the sintered body, and also has a wide energy band gap (6.2 eV), so that it can be used as a semiconductor laser element or a light emitting diode, or nitrided. Since gallium (GaN) has the same lattice constant and thermal expansion coefficient, it is expected to be used as a substrate material for semiconductor laser elements and light-emitting diodes. On the other hand, whiskers are also excellent in mechanical strength and heat dissipation, and thus are expected to be used as dispersion materials (fillers) for improving the mechanical strength and heat dissipation of metals and plastics.

As a method for producing an aluminum nitride single crystal, various methods such as a nitriding method, a flux method, a chemical transport method, a sublimation method, and a chemical vapor synthesis method are known. However, since aluminum nitride is a material that is stable against heat, it is difficult to melt even under high temperature conditions, and it is extremely difficult to grow crystals greatly. Therefore, there are very few reports of producing an aluminum nitride single crystal having a sufficiently large size that can be used as a substrate material.

To introduce some of the few reported examples, for example, a nitride powder is mixed with an oxide powder that reacts with the nitride under heating to decompose and vaporize the nitride. The nitride powder is decomposed and vaporized by heating at a temperature lower than the sublimation temperature or melting temperature of the nitride in a nitrogen atmosphere or the like, and the decomposition vaporized component is crystal-grown on the substrate from the gas phase. A method for producing a nitride single crystal has been reported (see, for example, Patent Document 1). According to this method, a sufficiently large aluminum nitride single crystal is obtained as a bulk material of 10 mm × 10 mm or more and a thickness of 300 μm or more.

Also, a bulk single crystal of aluminum nitride in which nitrogen is contacted with a melt of metal aluminum to form aluminum nitride in the melt and the aluminum nitride is deposited on a seed crystal that is in physical contact with the melt. The manufacturing method of (2) is also reported (for example, refer to Patent Document 2). According to this method, an aluminum nitride single crystal of 1 inch φ (about 2.5 cmφ) or more is obtained.
Japanese Patent Laid-Open No. 10-53495 Special table 2003-505331

However, the above method obtains an aluminum nitride single crystal having a practical size as a dispersing material for improving mechanical strength and heat dissipation or as a substrate material for electronic / electrical parts. Although it takes a long time to grow crystals, there is still room for improvement in terms of productivity.

Specifically, the method described in Patent Document 1 is considered to have a slow crystal growth rate because the retention time at the reaction temperature is as long as about 24 hours. The method described in Patent Document 2 also has a very slow crystal growth rate of about 1.6 mm / hour. Therefore, the above method cannot be said to be a production method capable of obtaining a sufficiently satisfactory crystal growth rate in consideration of practical use at an industrial level, and has a problem in terms of productivity. In addition, since the heating time at the reaction temperature becomes long, energy consumption is large and there is a problem in terms of production cost. That is, at present, a method for producing an aluminum nitride single crystal having high productivity and capable of obtaining an aluminum nitride single crystal having a practical size in a short time has not yet been disclosed. Creation of a new method is eagerly desired by the industry.

The present invention has been made to solve the above-described problems of the prior art, and can obtain an aluminum nitride single crystal having a practical size in a short time, and is said to have high productivity. An object of the present invention is to provide a method for producing an aluminum nitride single crystal that has an advantageous effect as compared with a conventional method.

As a result of earnest research to solve the above-mentioned problems, the present inventors synthesized aluminum nitride by heating a raw material composition containing alumina or the like in a nitrogen-containing atmosphere in the presence of carbon, and the nitriding In a method for producing an aluminum nitride single crystal, in which an aluminum nitride single crystal is obtained by crystal growth of aluminum, a metal oxide (specifically, Group 3A element oxidation that promotes crystal growth of aluminum nitride is included in the raw material composition. The present invention has been completed by finding that the above-mentioned problems can be solved by adding a compound, a Group 2A element oxide, etc.) . That is, according to the present invention, the following method for producing an aluminum nitride single crystal is provided.

[1] Nitriding by heating a raw material composition containing alumina (Al ₂ O ₃ ) and / or an alumina precursor converted to alumina by heating in the presence of carbon in an atmosphere containing nitrogen and / or nitrogen compounds A method of producing an aluminum nitride single crystal by synthesizing aluminum (AlN) and obtaining an aluminum nitride single crystal by crystal growth of the aluminum nitride, wherein the raw material composition includes the alumina and / or the alumina precursor. In addition, a material containing a Group 3A element oxide and / or a Group 3A element oxide precursor that is converted to a Group 3A element oxide by heating in the presence of carbon , By heating at a temperature of 1650 to 2200 ° C. in the presence of carbon in an atmosphere containing nitrogen compound, the alumina and / or the aluminum A method for producing an aluminum nitride single crystal, wherein a mina precursor is reduced and reacted with nitrogen to synthesize aluminum nitride, and crystal growth of the aluminum nitride yields an aluminum nitride single crystal.

[ 2 ] The aluminum nitride according to [1] , wherein the aluminum nitride crystal is grown on the surface of the plate-like body by causing a plate-like body made of a single crystal to exist in the reaction atmosphere during the reaction. A method for producing a single crystal.

The production method of the present invention can provide an aluminum nitride single crystal having a practical size in a short time, and has an advantageous effect as compared with the conventional method that the productivity is high. is there.

Hereinafter, the best mode for carrying out the method for producing an aluminum nitride single crystal of the present invention will be specifically described, but the production method of the present invention is not limited to the following embodiment.

In the method for producing an aluminum nitride single crystal of the present invention, an aluminum nitride is synthesized by heating a raw material composition containing alumina or the like in a nitrogen and / or nitrogen compound-containing atmosphere in the presence of carbon. An aluminum nitride single crystal manufacturing method for obtaining an aluminum nitride single crystal by crystal growth, and a metal oxide (specifically, a Group 3A element oxide for promoting crystal growth of aluminum nitride in a raw material composition ) ) And / or the metal oxide precursor converted into the metal oxide by heating.

Such a manufacturing method uses a short aluminum nitride single crystal having a practical size as a dispersing material for improving mechanical strength and heat dissipation or as a substrate material for electronic / electrical parts. Compared with the conventional method, it is advantageous in that it can be obtained in time and the productivity is high. In this specification, “aluminum nitride single crystal” includes whisker in addition to aluminum nitride bulk single crystal.

(1) Raw material composition In the manufacturing method of this invention, the raw material composition containing an alumina is used. As an aluminum source for the synthesis of aluminum nitride, in addition to alumina, metal aluminum or aluminum nitride crude crystals may be used, but this is not preferable in the following points. That is, although metal aluminum melts and volatilizes from a low temperature, there is a problem that a nitride film is easily formed on the surface of the melt, so that the volatilization and thus the synthesis reaction is hindered. In order to obtain a large single crystal, it is advantageous to perform synthesis and crystal growth at a high temperature. However, metallic aluminum that melts and volatilizes from a low temperature is not suitable for such a reaction. In addition, since the aluminum nitride crude crystal has a high sublimation temperature and a low speed, there is a problem that it is difficult to obtain a sufficient crystal growth speed at a low temperature. Although it is conceivable to grow the crystal at a high temperature, a special facility capable of handling such a high temperature is required, so that it lacks versatility. There is also a problem that the production cost is increased due to the high raw material cost.

On the other hand, when alumina is used as a raw material, for example, a reduction reaction as shown in the following formula (1) proceeds to generate Al ₂ O which is a gas molecule, and this Al ₂ O (or a derivative thereof) is nitrogen. It is said that aluminum nitride is produced by reacting with. Since the volatilization rate of Al ₂ O is higher than the sublimation rate of the above-mentioned aluminum nitride crude crystal, it is advantageous in that the crystal growth rate is increased. In addition, the crystal growth temperature is not so high, and there is an advantage that general-purpose equipment can be used. Furthermore, the raw material cost is lower than that of the aluminum nitride crude crystal, and the production cost can be kept low.
Al ₂ O ₃ + 2C → Al ₂ O + 2CO (1)

Further, since the production method of the present invention includes a step of heating the raw material composition at a high temperature, an alumina precursor that is converted into alumina by heating is used instead of part or all of the alumina contained in the raw material composition. May be. Examples of the alumina precursor include aluminum hydroxide (Al (OH) ₃ ), aluminum sulfate (Al ₂ (SO ₄ ) ₃ ), aluminum alkoxide (Al (RO) _3, where R is an alkyl group), and the like. However, it does not require a facility for removing by-product acidic gas like aluminum sulfate, and aluminum hydroxide can be suitably used in that the raw material cost is not expensive like metal alkoxide.

Although the form of these raw materials is not particularly limited, it is common to use a powdery form in that mixing is easy and the reaction proceeds easily.

In the production method of the present invention, it is necessary to use a raw material composition containing a metal oxide that promotes crystal growth of aluminum nitride in addition to alumina and / or an alumina precursor. By including such a metal oxide in the raw material composition, crystal growth of aluminum nitride is promoted, so that an aluminum nitride single crystal having a practical size can be produced in a short time. It becomes possible.

As the metal oxide, a Group 3A element (that is, rare earth element) oxide can be used. Among them, yttrium oxide (Y ₂ O ₃ ), cerium oxide (Ce ₂ O ₃ or CeO ₂ ), neodymium oxide (Nd ₂ O ₃ ), samarium oxide (Sm ₂ O ₃ ), europium oxide (Eu ₂ O ₃ ), It is particularly preferable to use ytterbium oxide (Yb ₂ O ₃ ) .

Since these metal oxides have a relatively high melting point and hardly volatilize even under high temperature conditions, they are suitable for aluminum nitride synthesis and crystal growth at high temperatures, which are advantageous for obtaining large single crystals. In addition, since the Group 3A element oxide has the same thermodynamic stability as that of alumina, it is considered that the fluctuation of the composition during crystal growth is reduced, and oxygen is captured to capture the single aluminum nitride. It is considered that a high-quality single crystal can be produced because it has an action of suppressing solid solution of oxygen in the crystal. Therefore, it can be said that it is more preferable to use a Group 3A element oxide as the metal oxide.

In addition, since the manufacturing method of this invention includes the process of heating a raw material composition at high temperature in carbon presence, it replaces with one part or all part of the said metal oxide contained in a raw material composition, and carbon presence exists. You may use the said metal oxide precursor converted into the said metal oxide by heating. Examples of the metal oxide precursor include Group 3A element hydroxides, sulfates, alkoxides, and the like. Thus, a hydroxide can be suitably used in that the raw material cost is not expensive.

Although the usage-amount of the said metal oxide is not specifically limited, The molar ratio of an alumina (as alumina conversion in the case of an alumina precursor) and the said metal oxide is in the range of 99.5: 0.5-77: 23. Preferably, it is in the range of 99.5: 0.5 to 82:18, more preferably 91.7: 8.3 (11: 1). If the amount is less than the above range, the amount of the metal oxide is insufficient, which is not preferable in that the effect of promoting crystal growth may not be sufficiently exerted. The formation of the nate is not preferable in that the effect of promoting crystal growth may not be sufficiently exhibited.

The raw material composition is obtained by weighing a predetermined amount of each raw material and mixing them by a conventionally known mixing method. Examples of the mixing method include a mixing method using a conventionally known mixer or a pulverizer (for example, a ball mill or a media pulverizer). When the amount of the raw material composition is small, the raw material composition may be mixed by a method (hand mixing) in which the raw material is put into a bag or a container and shaken.

(2) Synthesis and Crystal Growth of Aluminum Nitride In the production method of the present invention, the raw material composition is heated at a temperature of 1650 to 2200 ° C. in the presence of carbon in an atmosphere containing nitrogen and / or nitrogen compounds. By satisfying such conditions, the target aluminum nitride is synthesized, and the aluminum nitride crystal grows to obtain an aluminum nitride single crystal.

In the manufacturing method of the present invention, a nitrogen and / or nitrogen compound-containing atmosphere is supplied in order to supply a nitrogen source when synthesizing aluminum nitride and to make the reaction atmosphere a non-oxygen atmosphere in order to prevent oxidation of the generated aluminum nitride. It is necessary to carry out reaction and crystal growth in it. As the “nitrogen compound”, a nitrogen compound that can serve as a nitrogen source, for example, ammonia (NH ₃ ) or the like can be used. However, the method of performing the reaction and crystal growth in a nitrogen-containing atmosphere is advantageous in that a facility for removing nitrogen compounds such as ammonia discharged from the reaction system is unnecessary.

In the production method of the present invention, it is sufficient that the reaction atmosphere is an atmosphere containing nitrogen and / or a nitrogen compound, and other gases are contained as long as the synthesis reaction and crystal growth of aluminum nitride are not inhibited. It may be. For example, an inert gas such as helium (He) or argon (Ar) may be included in the reaction atmosphere.

The pressure of the reaction atmosphere is not particularly limited, but is preferably in the range of 1 kPa to 1 MPa, and particularly preferably in the range of 50 to 200 kPa. If it is less than the above range, the reduction of the metal oxide is likely to proceed, so that it is not preferable in that the effect of promoting crystal growth may not be sufficiently exhibited. Since raw materials such as metal oxides are easily nitrided, it is not preferable in that the effect of promoting crystal growth may not be sufficiently exhibited.

Further, the oxygen concentration in the reaction atmosphere is not particularly limited, but generally it is preferable to control the oxygen concentration within a range of 1 mol% or less. Exceeding the above range is not preferable in that the quality of the aluminum nitride crystal may deteriorate due to the solid solution of oxygen in the resulting crystal.

In the production method of the present invention, the reason why the reaction and crystal growth were performed “in the presence of carbon” was because alumina or the like was used as the aluminum source of aluminum nitride, so carbon as an alumina reducing agent was contained in the reaction system. Because it is necessary to exist.

Examples of the method of “in the presence of carbon” include a method in which a reaction vessel and a heating device are made of carbon. Specifically, a method using a graphite crucible as a reaction vessel, a method using a graphite heater as a heating device, and the like can be suitably used. Moreover, you may employ | adopt the method of containing carbon with a raw material composition.

As temperature conditions in the manufacturing method of this invention, it is necessary to set it as the range of 1650-2200 degreeC, and it is preferable to set it as the range of 1925 degreeC +/- 200 degreeC. If it is less than the above range, the amount of the liquid phase formed by the reaction between the metal oxide and alumina is insufficient, which is not preferable in that the effect of promoting crystal growth may not be sufficiently exhibited. When the above range is exceeded, the metal oxide is reduced, which is not preferable in that the effect of promoting crystal growth may not be sufficiently exhibited.

The optimum temperature condition in the production method of the present invention varies within the range of 1650 to 2200 ° C. depending on the type of metal oxide and other production conditions. In the production conditions, it is preferable that the temperature be not less than the temperature at which alumina and the metal oxide form a liquid phase and not more than the temperature at which the metal oxide is reduced.

Moreover, in the manufacturing method of this invention, it is preferable to make the plate-shaped body which consists of a single crystal exist in reaction atmosphere in the case of the said reaction. Thereby, the crystal of aluminum nitride can be grown on the surface of the plate-like body. This crystal growth is an epitaxial growth having the same orientation as that of the single crystal constituting the plate-like body, and is a high-quality aluminum nitride single crystal having a sufficient size that can be used as a substrate material or the like and having few crystal defects. Contributes to manufacturing. As a single crystal constituting the plate-like body, sapphire, silicon carbide (SiC) or the like can be suitably used as well as aluminum nitride.

As with the production method of the present invention, a method for synthesizing aluminum nitride by heating raw material powder containing alumina or an alumina precursor in a nitrogen atmosphere in the presence of carbon has been reported in the past. There are examples (see, for example, JP-A-1-308898, JP-A-2-64100, JP-A-9-118598, etc.).

However, in the methods reported in JP-A-1-308898 and JP-A-2-64100, whisker having a diameter of 1.0 μm and whisker having a diameter of 3 μm or less are obtained. This method is obviously different from the manufacturing method.

Further, in the method reported in JP-A-9-118598, a relatively large whisker having a diameter of about 10 mm is obtained, but in this method, a “solvent element-containing growth promoter” is used, Examples of the “solvent element” include silicon (Si), molybdenum (Mo), iron (Fe), nickel (Ni) and the like, and specific examples of the “solvent element-containing growth accelerator” include carbonyl iron. Yes. That is, the structure is different from the production method of the present invention in which the Group 3A element oxide is used as a crystal growth promoting substance, and an effect unique to the present invention cannot be obtained. In addition, when silicon, which is one of the solvent elements, is present in the reaction system, the silicon is dissolved in the aluminum nitride crystal, and the characteristics such as thermal conductivity are reduced. There is a fear.

Hereinafter, although the manufacturing method of the aluminum nitride single crystal of this invention is demonstrated concretely using an Example, the manufacturing method of this invention is not limited at all by these Examples. In addition, about the manufacturing method of an Example and a comparative example, it evaluated about the size (length, diameter) of the obtained aluminum nitride single crystal. The size (length, diameter) of the single crystal was evaluated by the following method.

[Single crystal size (length)]
The size (length) of the single crystal was evaluated by visually observing the inside of the reaction vessel after completion of the reaction. The evaluation criteria are “目視” when the largest crystal that can be visually confirmed has a length exceeding 10 mm, “◯” when the largest crystal that can be visually confirmed has a length of 1 mm to 10 mm, “◯”, 1 mm. When a crystal having the above length could not be visually confirmed, it was indicated as “x”.

[Single crystal size (diameter)]
The size (diameter) of the single crystal was evaluated by observing the inside of the reaction vessel after completion of the reaction with a scanning electron microscope (SEM). As an evaluation standard, when the largest crystal that can be confirmed with a scanning electron microscope has a diameter exceeding 0.2 mm, “「 ”, the largest crystal that can be confirmed with a scanning electron microscope is 0.01 mm or more and 0.2 mm or less. When a crystal having a diameter of 0.01 mm or more could not be confirmed with a scanning electron microscope, it was expressed as “X”.

(Example 1-12 and Comparative Example 1 to 9)
A raw material composition was prepared by mixing the aluminum source described in Table 1 and the metal oxide in the ratio described in Table 1. At this time, in Comparative Example 4 and Comparative Example 5, in addition to the aluminum source and the metal oxide, carbon powder serving as a carbon source was simultaneously added and mixed. The mixing was performed by a method in which an aluminum source and a metal oxide (in addition to the carbon source in Comparative Examples 4 and 5 were added in addition to this) were placed in a polyethylene bag and shaken.

For the raw material composition (or the mixture of the raw material composition and the carbon source) prepared as described above, synthesis of aluminum nitride is performed in a heating furnace 20 having a carbon heater 22 and a vacuum chamber 30 as shown in FIG. Crystal growth was performed. First, the raw material composition 10 is filled in a first crucible 12 (made of carbon: inner diameter 40 mmφ × height 50 mm) having an upper opening, and the first crucible 12 is similarly provided with an upper opening, A second crucible 14 (made of carbon: inner diameter 90 mmφ × height 70 mm) larger than one crucible is loaded, and an upper opening of the second crucible 14 is formed by a lid 16 (carbon: outer diameter 100 mmφ × thickness 5 mm). After closing the part, it was placed on the stage 24 inside the vacuum chamber 30 of the heating furnace 20.

The inside of the vacuum chamber 30 is depressurized to an internal pressure of 5 × 10 ⁻⁴ Pa by evacuating from the gas discharge port 28 by a vacuum pump, and then nitrogen gas is introduced from the gas introduction port 26. It adjusted so that it might become the nitrogen pressure of. Then, it heated up to the temperature of Table 1 with the temperature increase rate of 20 degreeC / min, and it hold | maintained at the temperature for 2 hours, Then, the furnace cooling was tried, and the synthesis | combination and crystal growth of aluminum nitride were tried. The results are shown in Table 1.

[Evaluation]
As shown in Table 1, according to the production methods of Examples 1 to 12 and Comparative Example 9 , it is practically possible to have a length of 1 mm or more and a diameter of 0.01 mm or more in a short time of 2 hours regardless of the conditions. A crystal with a size could be obtained. These crystals were analyzed by energy dispersive X-ray analysis (EDX), except that a very small amount of Group 3A element (or Group 2A element) and oxygen were detected at the forefront of the crystal. It was confirmed that the constituent elements were only aluminum and nitrogen. Moreover, it was confirmed by an X-ray diffraction method (XRD: X-ray Diffraction) that it is an aluminum nitride crystal. Further, observation with a scanning electron microscope revealed that the single crystal grew in the (0001) direction because the crystal shape was hexagonal.

Among the production methods of Examples 1 to 12 and Comparative Example 9, the production methods of Examples 1 to 3 and 6 to 12 can obtain crystals (whiskers) having a length of 20 mm or more and a diameter of 0.1 mm or more. Showed very good results. Moreover, although the favorable result was shown also about Example 4 with comparatively low nitrogen pressure, and Example 5 with comparatively high nitrogen pressure, the manufacturing method of Examples 1-3, 6-12 which showed the very favorable result As a result, the crystal length was slightly inferior. Furthermore, although the favorable result was shown also about the comparative example 9 using the calcium oxide which is a 2A group element oxide as a metal oxide, manufacture of Examples 1-3 and 6-12 which showed the very favorable result Compared to the method, the crystal diameter was slightly inferior. In the production method of Example 4, not only whiskers but also a bulk single crystal having a diameter of several mmφ and a thickness of several mm was obtained. In the future, it is expected that larger bulk single crystals can be obtained by examining manufacturing conditions in detail.

On the other hand, in the production method of Comparative Example 1 in which the metal oxide was not contained in the raw material composition, crystals having a length of 1 mm or more and crystals having a diameter of 0.01 mm or more could not be confirmed at all. Under similar conditions, when the reaction temperature is high (Comparative Examples 2 and 3), and when carbon powder as a carbon source is mixed with the raw material composition (Comparative Examples 4 and 5), the formation and growth of aluminum nitride crystals Was not recognized.

On the other hand, in the production method of Comparative Example 6 using aluminum nitride as the aluminum source, crystals having a length of 1 mm or more and crystals having a diameter of 0.01 mm or more could not be confirmed at all. Under the same conditions, formation and growth of aluminum nitride crystals were not observed even when the reaction temperature was high (Comparative Example 7) and when europium oxide was mixed as the metal oxide (Comparative Example 8).

The method for producing an aluminum nitride single crystal of the present invention is based on a dispersion material (filler) for improving the mechanical strength and heat dissipation of metals and plastics, and on the basis of electronic / electrical parts such as semiconductor laser elements and light-emitting diodes. It can be suitably used for the production of aluminum nitride single crystals (bulk single crystals or whiskers) that are promising as plate materials, heat dissipation materials, or structural materials.

It is a schematic sectional drawing of the heating furnace which can be used for the manufacturing method of the aluminum nitride single crystal of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Raw material composition, 12 ... 1st crucible, 14 ... 2nd crucible, 16 ... Lid body, 20 ... Heating furnace, 22 ... Carbon heater, 24 ... Stage, 26 ... Gas inlet, 28 ... Gas outlet 30 ... Vacuum chamber.

Claims (2)

By heating a raw material composition containing alumina (Al ₂ O ₃ ) and / or an alumina precursor converted to alumina by heating in a nitrogen and / or nitrogen compound-containing atmosphere in the presence of carbon, aluminum nitride (AlN And producing a single crystal of aluminum nitride by crystal growth of the aluminum nitride,
As the raw material composition, in addition to the alumina and / or the alumina precursor, a group 3A element oxide which is converted into a group 3A element oxide by heating in the presence of a group 3A element oxide and / or carbon . Use the one containing the precursor,
By heating the raw material composition in a nitrogen and / or nitrogen compound-containing atmosphere at a temperature of 1650 to 2200 ° C. in the presence of carbon, the alumina and / or the alumina precursor is reduced and reacted with nitrogen. A method for producing an aluminum nitride single crystal, in which aluminum nitride is synthesized and an aluminum nitride single crystal is obtained by crystal growth of the aluminum nitride. Wherein during the reaction, by the presence of plate-shaped body made of single crystal in a reaction atmosphere, the surface of the plate-like body, the production of the aluminum nitride single crystal according to claim 1 for crystal growth of the aluminum nitride Method.

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