JP2005263622A - Method of manufacturing compound single crystal and apparatus for manufacturing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a compound single crystal, especially a group III nitride single crystal such as potassium nitride or aluminum nitride, which method is capable of improving a growth rate and growing a single crystal with a high crystal uniformity and a large size in a short time; and an apparatus for manufacturing it. <P>SOLUTION: The compound single crystal is grown while a raw material liquid is being stirred so that the liquid flows from a gas-liquid interface contacting with a raw material gas toward the inside of the liquid. By this stirring, the raw material gas is easily dissolved in the raw material liquid and the supersaturation is attained in a short time to improve the growth rate of the compound single crystal. Since the flow from the gas-liquid interface where the raw material gas concentration is high toward the inside of the raw material liquid where the raw material gas concentration is low, is formed and the dissolution of the raw material gas is homogenized by this mixing, ununiform nucleus formation at the gas-liquid interface is suppressed and the quality of the obtained compound single crystal is improved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a compound single crystal and a production apparatus used therefor. In particular, the present invention relates to a method for producing a group III nitride single crystal such as gallium nitride or aluminum nitride, and a production apparatus used therefor.

  Group III nitride compound semiconductors such as gallium nitride (GaN) (hereinafter sometimes referred to as group III nitride semiconductors or GaN-based semiconductors) are attracting attention as materials for semiconductor elements that emit blue or ultraviolet light. Blue laser diodes (LDs) are applied to high density optical discs and displays, and blue light emitting diodes (LEDs) are applied to displays and illuminations. In addition, the ultraviolet LD is expected to be applied to biotechnology and the like, and the ultraviolet LED is expected as an ultraviolet light source for fluorescent lamps.

  A group III nitride semiconductor (for example, GaN) substrate for LD or LED is usually formed by heteroepitaxially growing a group III nitride single crystal on a sapphire substrate using a vapor phase epitaxial growth method. . Examples of the vapor deposition method include a metal organic chemical vapor deposition method (MOCVD method), a hydride vapor deposition method (HVPE method), a molecular beam epitaxy method (MBE method), and the like.

On the other hand, a method of performing crystal growth in a liquid phase instead of vapor phase epitaxial growth has been studied. Since the equilibrium vapor pressure of nitrogen at the melting point of a group III nitride single crystal such as GaN or AlN is 10,000 atm or higher, conventionally, GaN is grown at 1200 ° C. (1473 K) at 8000 atm (8000 m) in the liquid phase. The condition of × 1.01325 × 10 ⁵ Pa) has been required. On the other hand, in recent years, it is clear that GaN can be synthesized at a relatively low temperature and low pressure of 750 ° C. (1023 K) and 50 atm (50 × 1.01325 × 10 ⁵ Pa) by using an alkali metal such as Na as a flux. It was done.

Recently, a mixture of Ga and Na is melted at 800 ° C. (1073 K) and 50 atm (50 × 1.01325 × 10 ⁵ Pa) in a nitrogen gas atmosphere containing ammonia, and this molten solution (raw material solution) is used. Thus, a single crystal having a maximum crystal size of about 1.2 mm is obtained in a growth time of 96 hours (see, for example, Patent Document 1).

  In addition, after forming a GaN crystal layer on a sapphire substrate by metal organic chemical vapor deposition (MOCVD) method, a single crystal is grown by liquid phase epitaxy (LPE) method. It has been reported.

Hereinafter, a liquid phase growth method of a GaN crystal using an alkali metal such as Na as a flux will be described. FIG. 8 shows a schematic configuration diagram of the growing apparatus. The growth apparatus includes a raw material gas supply device 801 for supplying nitrogen gas as a raw material gas, a pressure regulator 802 for adjusting the pressure of the growth atmosphere, a reaction vessel (stainless steel vessel) 803 for performing crystal growth, and A heating device (electric furnace) 804 is provided. A crucible 805 is set inside the stainless steel container 803. A SUS-based material is used for the connection pipe 806 for supplying the source gas from the source gas supply device 801 to the stainless steel container 803. For the crucible 805, alumina (Al ₂ O ₃ ) is used. The temperature in the electric furnace 804 can be controlled to 600 ° C. (873 K) to 1100 ° C. (1373 K). The atmospheric pressure can be controlled by the pressure regulator 802 within a range of 100 atm (100 × 1.01325 × 10 ⁵ Pa) or less. In FIG. 8, 807 indicates a stop valve, and 808 indicates a leak valve.

A predetermined amount of Na, which is a flux, and metallic gallium, which is a raw material, are weighed and set in a crucible 805. In addition, a substrate obtained by growing GaN on the sapphire substrate as a seed crystal by MOCVD (Metal Organic Chemical Vapor Deposition) method is set in the crucible 805. The crucible 805 is inserted into the stainless steel container 803, set in the electric furnace 804, and connected to the connection pipe 806 connected to the source gas supply device 801. The growth temperature is 850 ° C. (1123 K), the nitrogen atmosphere pressure is 30 atm (30 × 1.01325 × 10 ⁵ Pa), and the growth temperature is maintained for 30 hours and 96 hours to grow a GaN single crystal. A GaN single crystal having a thickness of 50 μm grows for a growth time of 30 hours, and a 700 μm thickness for a growth time of 96 hours.

  From this result, the current growing apparatus requires about 20 to 30 hours to dissolve nitrogen in the Ga / Na melt (raw material solution) to form a supersaturated state. The growth rate in the thickness direction (C-axis direction) is about 10 μm / hour.

However, in the field of group III nitride single crystals including GaN, further growth rate and quality improvements are required.
JP 2002-293696 A

  In order to improve the growth rate, it is necessary to efficiently dissolve the raw material gas in the raw material liquid (which may include a flux raw material). However, for example, in the conventional liquid phase growth method of a nitride semiconductor single crystal using alkali metal or alkaline earth metal such as Na as a flux, a source gas such as nitrogen is pressurized and dissolved in the source liquid. Non-uniform nucleation is likely to occur at the liquid interface. When nucleation occurs at the gas-liquid interface, crystal growth on the seed crystal to be originally grown is suppressed, and as a result, the growth rate decreases.

  Accordingly, an object of the present invention is to provide a method for producing a compound single crystal capable of improving a growth rate and growing a large single crystal with high crystal uniformity in a short time, and a production apparatus used therefor.

  In order to achieve the above object, the production method of the present invention is a method for producing a compound single crystal in which a raw material gas and a raw material liquid are reacted to grow a compound single crystal, and in the raw material liquid, In the production method, the single crystal is grown while stirring the raw material liquid so that a flow is generated from the gas-liquid interface in contact with the raw material liquid.

  The present inventors have made a series of studies on the growth of compound single crystals. In the process, it is important to dissolve the raw material gas in the raw material solution in a supersaturated state and to suppress non-uniform nucleation at the gas-liquid interface in the growth of the single crystal. Got the recognition that it is one of Therefore, in the present invention, as described above, this problem is solved by stirring the raw material liquid so that a flow occurs in the raw material liquid from the gas-liquid interface in contact with the raw material gas toward the inside of the raw material liquid. did. That is, by the stirring, the source gas can be easily dissolved in the source solution, and a supersaturated state can be realized in a short time, and the growth rate of the compound single crystal can be improved. In addition, the agitation creates a flow from the gas-liquid interface having a high source gas concentration to the inside of the source liquid having a low source gas concentration, so that the source gas is uniformly dissolved, so that non-uniform nucleation occurs at the gas-liquid interface. And the quality of the resulting compound single crystal is improved.

  In the production method of the present invention, a single crystal production apparatus having a heating device and a hermetic pressure-resistant heat-resistant container heated inside the heating device is prepared, and the raw material gas of the compound single crystal and other raw materials in the container And sealed in a pressurized atmosphere, the container is housed in the heating device, the container is heated by the heating device to liquefy the other raw materials, and in this state, It is preferable to grow the single crystal by reacting the raw material gas and the raw material solution while stirring the raw material solution. Because the hermetic pressure-resistant and heat-resistant container can be kept in a pressurized atmosphere by putting the raw material gas and other raw materials without holding the state connected to the raw material gas supply device by the connection pipe because of its tightness, It can be separated from the connecting pipe and swung, and the raw material liquid can be freely stirred. On the other hand, it has been difficult for the conventional crystal growth apparatus to stir the raw material liquid because of its structure. That is, in the apparatus shown in FIG. 8, the raw material gas supply device 801 and the stainless steel container 803 are connected by the connection pipe 806 made of SUS, and therefore the stainless steel container 803 is in a fixed state. Further, as will be described later, in the present invention, the hermetic pressure-resistant and heat-resistant container may be swung without disconnecting the connection pipe by taking measures such as using a flexible pipe.

  In the production method of the present invention, it is preferable to grow a single crystal by reacting the raw material gas and the raw material solution while stirring the raw material solution by swinging the container.

  In the manufacturing method of the present invention, it is preferable that the container is rocked by rocking the heating device.

In the production method of the present invention, a crucible is installed in the container, and at least one of the inside of the crucible and the inner wall surface is selected from the group consisting of the following (A), (B), (C) and (D). It is preferable to have at least one of the following.
(A) Stirrer blade (B) Baffle plate (C) Template (D) Spiral protrusion The template of (C) is, for example, a template described later.

  In the manufacturing method of the present invention, examples of the swing include a moving motion, a linear repetitive motion, a pendulum repetitive motion, a rotational motion, or a combination motion thereof. For example, if the raw material liquid is stirred so that a flow is generated from the gas-liquid interface toward the inside of the raw material by combining the linear repetitive motion, the rotational motion, or the like, the gas-liquid having a high raw material gas concentration Since a flow from the interface to the inside of the raw material liquid having a low raw material gas concentration is formed and uneven nucleation on the inner wall surface of the hermetic pressure-resistant heat-resistant container can be suppressed, a large growth rate can be realized.

  In the production method of the present invention, the other raw material preferably contains a flux raw material.

  In the production method of the present invention, the single crystal production apparatus further includes a raw material gas supply device, and supplies the raw material gas by connecting the raw material gas supply device to the container in which the other raw materials are placed, After the supply is completed, it is preferable to disconnect the source gas supply device from the container and then swing the container.

  In the production method of the present invention, it is preferable that after the container is heated to make the other raw materials liquid and the pressure in the container is adjusted, the raw material gas supply device is disconnected from the container.

  In the manufacturing method of this invention, it is preferable that the pressure of the said raw material gas in the said container after the production | generation of a single crystal is reducing.

  In the production method of the present invention, the single crystal production apparatus may further include an auxiliary tank device for supplying a source gas, and the auxiliary tank device and the container may be connected.

  In the manufacturing method of the present invention, the single crystal manufacturing apparatus further includes a source gas supply device, the source gas supply device and the container are connected by a flexible pipe, and the source gas supply device and the container are connected to each other. The container may be swung without being separated. In addition, another manufacturing method of the present invention using a flexible pipe prepares a single crystal manufacturing apparatus, a raw material gas supply apparatus, and a flexible pipe having a heating device and a hermetic pressure-resistant heat-resistant container that heats inside the heating device. The raw material gas of the compound single crystal and other raw materials are put into the container, the container is accommodated in the heating device, the raw material gas supply device and the container are connected by a flexible pipe, In the manufacturing method, the container is heated by a heating device to make the other raw materials liquid, and the raw material gas and the raw material liquid are reacted in this state to grow a single crystal. Note that whether or not to separate the source gas supply device and the container is arbitrary, and as described above, the source material can be swung without disconnecting the source gas supply device and the container. Either the gas supply device and the container may be separated, the container may be sealed, and the container may be swung. If the container is swung without separating the source gas supply device and the container, crystal growth can be performed stably while keeping the pressure of the container constant by a pressure regulator. A constant growth direction and growth rate can be realized, which is more preferable.

  In the production method of the present invention, the source gas contains at least one of nitrogen and ammonia, and the other source material includes a group III element (gallium, aluminum, or indium) and a flux source, and is generated in the source solution. The single crystal to be formed is preferably a group III nitride single crystal. In addition, the said group III element may be used individually by 1 type, or may use 2 or more types together.

  In the production method of the present invention, the flux raw material preferably contains at least one of an alkali metal and an alkaline earth metal. In this case, in the conventional manufacturing method, for example, when the growth temperature is set to 700 ° C. (973 K) or higher, the vapor pressure of the alkali metal or alkaline earth metal increases, so that the temperature distribution is present in the reaction vessel. If it occurs, it will aggregate. As a result, the flux ratio of the raw material solution changes, which greatly affects crystal growth. Further, even when a stirring motor is attached to the reaction vessel, the reaction vessel is in a high temperature region in the heating device, so that the magnetic force is lost and it is difficult to stir the raw material liquid. On the other hand, in the manufacturing method of this invention, since the said raw material liquid can be stirred, even if it uses the said alkali metal and alkaline-earth metal, a problem does not arise. In addition, as said alkali metal, sodium, lithium, potassium, etc. can be used, for example. As the alkaline earth metal, for example, Ca, Mg, Sr, Ba, Be and the like can be used. The alkali metal and alkaline earth metal may be used alone or in combination of two or more.

In the manufacturing method of the present invention, a semiconductor layer represented by the composition formula Al _u Ga _v In _1-uv N (where 0 ≦ u ≦ 1, 0 ≦ v ≦ 1, 0 ≦ u + v ≦ 1) is contained in the container. It is preferable that the template which has is arrange | positioned previously.

  In the production method of the present invention, in the container, the immersion of the template in the other raw material liquid is preferably performed after the raw material liquid is formed by heating and the raw material gas is dissolved in the raw material liquid. .

  In the production method of the present invention, it is preferable that a crucible is installed in the container, the template is a plate template, and is installed in a state of standing substantially vertically on the bottom surface of the crucible. Still another manufacturing method of the present invention using a plate-shaped template is to prepare a single crystal manufacturing apparatus having a heating device and a hermetic pressure-resistant and heat-resistant container that is heated inside the heating device. A crucible is installed, a plate-like template is placed in a state of being substantially perpendicular to the bottom surface of the crucible, a raw material gas of the compound single crystal and other raw materials are placed in the crucible, and a container in which the crucible is installed A manufacturing method in which the container is heated in the heating device, the container is heated by the heating device to make the other raw materials liquid, and in this state, the raw material gas and the raw material liquid are reacted to grow a single crystal. is there. In this method, the plate-shaped template may be a single plate or a plurality of plates (for example, 2 to 10 plates). Moreover, since the plate-like template may be raised in a substantially vertical state, it may be slightly inclined.

  In the manufacturing method of the present invention, it is preferable that the container is swung so that the raw material liquid moves in a direction parallel to the plate template.

  In the production method of the present invention, it is preferable to take out at least the flux raw material from the container after the growth of the compound single crystal. Further, still another manufacturing method of the present invention having a flux raw material take-out step is to prepare a single crystal manufacturing apparatus having a heating device and a hermetic pressure-resistant heat-resistant container that is heated inside the heating device. The raw material gas of the compound single crystal and other raw materials are put in, the container is housed in the heating device, the container is heated by the heating device to make the other raw materials liquid, and in this state, the raw material This is a production method in which a single crystal is grown by reacting a gas and the raw material liquid, and at least the flux raw material is taken out from the container after the growth of the compound single crystal is completed.

  In the production method of the present invention, the other raw material liquid preferably contains at least gallium and sodium, and the heating temperature is preferably 100 ° C. (373 K) or higher, and the heating temperature is 300 ° C. (573 K) or higher. More preferably, the heating temperature is more preferably 500 ° C. (773 K) or more.

  In the production method of the present invention, the growth rate of the group III nitride single crystal is preferably 30 μm / hour or more, and the growth rate of the group III nitride crystal is more preferably 50 μm / hour or more. The growth rate of the group III nitride crystal is more preferably 100 μm / hour or more.

In the production method of the present invention, the pressure of the source gas in the container is 5 atm (5 × 1.01325 × 10 ⁵ Pa) or more and 1000 atm (1000 × 1.01325 × 10 ⁵ Pa) or less. preferable. This is because the amount of the raw material gas dissolved in the raw material liquid can be increased by applying pressure.

  In the production method of the present invention, it is preferable that the heating apparatus is filled with an inert gas.

In the production method of the present invention, when gallium is contained in the other raw material, the internal volume of the container is set to the weight X (g) and atomic weight a (= 69.723) of the gallium consumed. When V (liter), the atmospheric pressure during growth (generation of a single crystal) is P (Pa), the growth temperature is T (K), and the temperature during weighing of the other raw materials is T1 (K), the following formula It is preferable to satisfy (1), more preferable to satisfy the following formula (2), and further preferable to satisfy the following formula (3).
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 2 (1)
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 5 (2)
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 10 (3)

  In the production method of the present invention, in the single crystal production apparatus, the pipe connecting the container housed in the heating device and the outside of the heating device has a structure that hardly aggregates at least one of the raw material liquid and the other raw materials. It is preferable that Examples of the pipe include a connection pipe between the container and the source gas supply device, a flexible pipe, a connection pipe between the container and the auxiliary tank device, and the like.

  In the production method of the present invention, the inner diameter of the pipe is preferably 3 mm or less, and more preferably 2 mm or less.

  The single crystal production apparatus of the present invention is a single crystal production apparatus used in the production method of the present invention, and includes the hermetic pressure-resistant and heat-resistant container, a heating apparatus that houses the container therein, and a shaker of the container. A single crystal manufacturing apparatus including a moving rocking device.

  In the single crystal manufacturing apparatus of the present invention, it is preferable that the container swings together with the heating device.

  In the single crystal manufacturing apparatus of the present invention, examples of the swing include a moving motion, a linear repetitive motion, a pendulum repetitive motion, a rotational motion, or a combination motion thereof.

In the single crystal production apparatus of the present invention, a crucible is installed inside the container, and at least one of the inside of the crucible and the inner wall surface is selected from the group consisting of the following (A), (B), (C) and (D). It is preferable to have at least one selected.
(A) Stirrer blade (B) Baffle plate (C) Template (D) Spiral protrusion The template of (C) is, for example, a template described later.

  In the single crystal manufacturing apparatus of the present invention, it is preferable that the container is accommodated in the heating container so as to be maintained at a constant temperature. When the raw material liquid contains an alkali metal or an alkaline earth metal, for example, when the growth temperature is set to 700 ° C. (973 K) or higher, the vapor pressure increases, and thus when the temperature distribution occurs in the container, This is because the raw material liquid aggregates and may have a great influence on crystal growth.

  The single crystal production apparatus of the present invention preferably further includes a source gas supply apparatus.

  In the single crystal production apparatus of the present invention, it is preferable that the container and the source gas supply apparatus can be connected and disconnected.

  The single crystal production apparatus of the present invention may further include a flexible pipe, whereby the container and the source gas supply apparatus may be connected.

  The single crystal manufacturing apparatus of the present invention may further include an auxiliary tank device for supplying a source gas, and the auxiliary tank device may be connected to the container.

  Next, as an embodiment of the present invention, an example of a method for producing a compound single crystal of the present invention will be described by taking a method for producing a group III nitride single crystal as an example.

In the method for producing a group III nitride single crystal of the present invention, for example, a group III element (gallium) under an atmosphere containing nitrogen (preferably a pressurized atmosphere of 1000 atm (1000 × 1.01325 × 10 ⁵ Pa) or less). , Aluminum or indium) and a raw material solution containing an alkali metal and nitrogen are reacted to grow a group III nitride single crystal. In addition, as above-mentioned, the said group III element may be used individually by 1 type, or may use 2 or more types together. The alkali metal is also as described above. As the atmosphere containing nitrogen, for example, a nitrogen gas atmosphere or a nitrogen gas atmosphere containing ammonia can be applied.

(Embodiment 1)
In this embodiment, the hermetic pressure-resistant and heat-resistant container can be separated from the connection pipe, and the hermetic pressure-resistant and heat-resistant container is also swung by swinging the heating device. Hereinafter, an example of the manufacturing apparatus of this embodiment and an example of a manufacturing method using the same will be described.

The manufacturing apparatus shakes a raw material gas supply device for supplying a raw material gas, a pressure regulator for adjusting the pressure of the growth atmosphere, a hermetic pressure-resistant heat-resistant container for crystal growth, a heating device, and the entire heating device. A moving oscillating device is provided. A gas containing nitrogen or ammonia is used as the source gas. For the hermetic pressure-resistant and heat-resistant container, for example, a SUS-based material such as SUS316 or a material resistant to high temperature and pressure such as Inconel, Hastelloy, or Incoloy can be used. In particular, materials such as Inconel, Hastelloy or Incoloy are resistant to oxidation at high temperature and pressure, can be used in an atmosphere other than inert gas, and are preferable from the viewpoint of reuse and durability. A crucible is set inside the hermetic pressure and heat resistant container. For the crucible material, for example, alumina (Al ₂ O ₃ ), BN, PBN, MgO, CaO, W, or the like can be used. For example, an electric furnace composed of a heat insulating material and a heater can be used as the heating device. It is preferable that the heating device is housed in a growth furnace, and the temperature is controlled by, for example, a thermocouple. In particular, from the viewpoint of preventing aggregation of the raw material liquid (which may include a flux raw material), it is preferable to perform temperature control so that the temperature of the hermetic pressure-resistant and heat-resistant container is maintained uniformly.

The temperature in the heating device (growing furnace) can be controlled to, for example, 600 ° C. (873 K) to 1100 ° C. (1373 K). The atmospheric pressure can be controlled by a pressure regulator, for example, in the range of 1000 atm (1000 × 1.01325 × 10 ⁵ Pa) or less. Since the hermetic pressure-resistant and heat-resistant container can be separated freely, the hermetic pressure-resistant and heat-resistant container can be fixed in the heating apparatus (growing furnace) and the entire heating apparatus (growing furnace) can be swung.

  By inserting an alkali metal as a flux and a group III element into the crucible and filling a reactive gas containing nitrogen in a hermetic pressure-resistant heat-resistant vessel, a group III nitride single crystal is formed by liquid phase growth. Can be manufactured. In a pressurized atmosphere containing nitrogen, nitrogen is dissolved in a raw material liquid containing a group III element (gallium, aluminum, or indium) and an alkali metal to grow a group III nitride crystal. The raw material liquid may further contain an alkaline earth metal. As described above, the group III element may be used alone or in combination of two or more. The alkali metal and alkaline earth metal are also as described above. As described above, when the alkali metal or the alkaline earth metal is contained in the raw material liquid, the vapor pressure increases at a high temperature of 700 ° C. (973 K) or higher, so that the temperature distribution in the hermetic pressure and heat resistant container When this occurs, the raw material liquid aggregates. For example, the vapor pressure of sodium at 800 ° C. (1073 K) is 300 Torr (300 × 133.322 Pa), and when the raw material liquid contains sodium, the temperature distribution is almost 10 ° C. (= 10 K) or less. Although aggregation is not observed, aggregation is observed at 20 ° C. (= 20K) or higher, and most of the raw material liquid is aggregated at a low temperature portion at 50 ° C. (= 50K) or higher. Therefore, it is preferable to keep the temperature of the hermetic pressure and heat resistant container uniform.

The raw material liquid is prepared by charging a raw material into a crucible and heating it. The temperature is adjusted to, for example, 700 ° C. (973K) to 1100 ° C. (1373K). The source gas containing nitrogen is preferably filled in a hermetic pressure-resistant and heat-resistant container in a pressurized atmosphere, and the atmospheric pressure in the hermetic pressure-resistant and heat-resistant container is preferably adjusted after heating. The atmospheric pressure is adjusted to, for example, about 1 atmosphere (1 × 1.01325 × 10 ⁵ Pa) to 1000 atmospheres (1000 × 1.01325 × 10 ⁵ Pa). After the raw material liquid is formed, a group III nitride crystal is deposited when the raw material liquid is supersaturated with nitrogen.

A template may be inserted into the crucible. A template is a semiconductor layer represented by a composition formula Al _u Ga _v In _1-uv N (where 0 ≦ u ≦ 1, 0 ≦ v ≦ 1, 0 ≦ u + v ≦ 1) on a substrate such as sapphire. Or a single crystal represented by the composition formula Al _u Ga _v In _{1 -uv} N (where 0 ≦ u ≦ 1, 0 ≦ v ≦ 1, 0 ≦ u + v ≦ 1). By inserting the template as a seed crystal into the crucible, a thick single crystal can be grown on the template, and a large-area substrate can be easily realized. The template may be immersed at the time of forming the raw material liquid, but it is more preferable that the template is immersed in a state where nitrogen is dissolved in the raw material liquid to some extent.

  Next, an example of a method for producing a group III nitride single crystal using the production apparatus will be specifically described with reference to FIG.

As shown in FIG. 2A, a crucible 107 is filled with a group III element 201 as a raw material, an alkali metal 202 as a flux, and a sapphire substrate with a composition formula Al _u Ga _v In _{1 -uv} N (where 0 ≦ u A template 203 having a semiconductor layer represented by ≦ 1, 0 ≦ v ≦ 1, 0 ≦ u + v ≦ 1) is inserted. The weighing of the group III element 201 and the alkali metal 202 is preferably performed in a glove box substituted with nitrogen in order to avoid oxidation of the alkali metal 202 and moisture adsorption. More preferably, the inside of the glove box is replaced with Ar, Ne or the like.

  Next, as shown in FIG. 2B, the crucible 107 is inserted into the hermetic pressure and heat resistant container 103, and the upper lid 204 is closed. After closing the stop valve 109, it is taken out from the glove box.

  Next, the sealed pressure and heat resistant container 103 is connected to a source gas supply device (not shown), the stop valve 109 is opened, and the source gas is injected into the sealed pressure and heat resistant container 103. At this time, although not shown, it is preferable to perform a step of evacuating the hermetic pressure-resistant and heat-resistant container 103 with a rotary pump or the like and then injecting and replacing the source gas again.

  Next, as shown in FIG. 2 (c), the stop valve 109 is closed, and the separation portion 108 is removed, thereby separating.

  Note that the same effect can be obtained by injecting the raw material gas in the glove box, and then disconnecting by closing the stop valve 109 and removing the disconnecting portion 108.

Next, the hermetic pressure-resistant and heat-resistant container 103 is fixed in a heating apparatus (growing furnace). The conditions for melting and crystal growth of the raw material vary depending on the flux component, the atmospheric gas component, and the pressure thereof. For example, the temperature is 700 ° C. (973 K) to 1100 ° C. (1373 K), preferably 700 ° C. (973 K) to 900. The growth is performed at a low temperature of 1 ° C. (1173 K). The pressure is 1 atm (1 × 1.01325 × 10 ⁵ Pa) or more, preferably 5 atm (5 × 1.01325 × 10 ⁵ Pa) or more and 1000 atm (1000 × 1.01325 × 10 ⁵ Pa) or less. Is called. By raising the temperature to the growth temperature, the raw material liquid is formed in the crucible, the heating device (growth furnace) is swung, the raw material liquid is stirred, and the raw material liquid and the raw material gas are reacted in a hermetic pressure-resistant heat-resistant vessel. Thus, a group III nitride semiconductor single crystal is produced. When the internal volume of the hermetic pressure-resistant and heat-resistant container is small with respect to the amount of the group III element consumed, the pressure in the hermetic pressure-resistant and heat-resistant container decreases due to consumption of nitrogen. In this case, the rocking is temporarily stopped during the growth, the separation part 108 is connected again to the raw material gas supply device, the raw material gas is injected into the hermetic pressure resistant heat resistant container, and the pressure in the hermetic pressure resistant heat resistant container is adjusted. To do. Thereafter, the separation part 108 is separated again, and the growth is resumed while swinging. Thereby, more stable cultivation becomes possible.

The heating device (growing furnace) is preferably filled with an inert gas. If the hermetic pressure-resistant and heat-resistant container is kept at a high temperature in the air, it is oxidized and becomes difficult to reuse. By holding the hermetic pressure-resistant and heat-resistant container in an inert gas such as Ar, N ₂ , He, or Ne, the hermetic pressure-resistant and heat-resistant container can be reused.

  In addition, although it isolate | separated by the isolation | separation part 108 and it fixed to the heating apparatus (growth furnace), in this case, it is difficult to finely adjust the pressure in the airtight pressure-proof heat-resistant container 103. Therefore, it is more preferable that the hermetic pressure-resistant and heat-resistant vessel 103 is fixed to a heating device (growing furnace), heated to a growing temperature, adjusted in pressure, and then cut off at the cut-off portion 108.

  The stirring action of the raw material liquid will be described with reference to FIG. First, as shown in FIG. 6A, by tilting the heating device (growing furnace) (not shown), the crucible 601 fixed therein is tilted, and the template 603 is not immersed in the raw material liquid 602. In the state, the heating device (growing furnace) is heated to melt the raw material. Next, after setting to a desired growth temperature and growth pressure, the raw material liquid is shaken and stirred by rocking the heating device (growth furnace) and the crucible 601 left and right (FIGS. 6B to 6D). .

  In FIG. 6, the template 603 is fixed to the lower surface of the crucible 601, but in this case, the template is immersed in a state where the dissolution of nitrogen in the raw material liquid 602 is insufficient. More preferably, after melting the raw material, the crucible is swung to sufficiently dissolve nitrogen, and then the template is immersed.

  FIG. 2 and FIG. 6 illustrate a method in which a template, which is a seed crystal, is installed at the bottom of the crucible or installed obliquely. However, in order to supply a crystal substrate at a low cost, it is indispensable to simultaneously grow a plurality of crystals. Here, it has been found that when a plurality of plate-shaped templates are installed obliquely or parallel to the bottom of the crucible, a big problem occurs.

  FIG. 9 shows a state in which a plurality of plate-like templates 902 are installed in the crucible 901 in parallel with the bottom surface. FIG. 9A shows the state of the raw material liquid 902 and the plate template 903 in the crucible 901 being grown. FIG. 9B shows a state of the raw material liquid 902 and the plate template 903 in the crucible 901 after the raw material liquid 903 is cooled after the growth. A raw material liquid composed of an alkali metal and a group III element solidifies and shrinks when cooled. Therefore, as shown in FIG. 9B, the central portion has a concave shape, and stress is generated in the direction of the arrow on the plate-like template 903. Due to this stress, the substrate is distorted, and cracks occur when the stress is large.

  Based on the above results, as shown in FIG. 10, it was examined that a plurality of plate-like templates 1003 are installed in a state of being substantially perpendicular to the bottom surface of the crucible 1001.

  A crucible 1001 is set inside a hermetic pressure and heat resistant container (not shown). Next, the hermetic pressure-resistant and heat-resistant container is connected to the raw material gas supply device, the stop valve is opened, and the raw material gas is injected into the hermetic pressure-resistant and heat-resistant container (not shown). Inside the crucible 1001, a group III element as a raw material and an alkali metal as a flux are inserted. At the same time, a plurality of plate-like templates 1003 are installed in a state where they stand substantially vertically on the bottom surface of the crucible 1001 as shown in FIG. FIG. 10A is a side view of the plate template 1003 as viewed from the lateral direction.

  By fixing the hermetic pressure-resistant and heat-resistant container to a heating device (growing furnace) (not shown) and setting the desired growth temperature and pressure, the heating device (growing furnace) and the crucible 1001 are swung left and right. The raw material liquid is shaken and stirred (FIGS. 10B to 10D). 10B to 10D are front views of the plate template 1003 as viewed from the front.

  As shown in FIGS. 10B to 10D, it is preferable to swing the hermetic pressure and heat resistant container so that the raw material liquid moves in a direction parallel to the plate template. Thereby, it can prevent that a plate-shaped template obstructs stirring of a raw material liquid, the flow of a raw material liquid can be formed between plate-shaped templates, and uniform crystal growth can be accelerated | stimulated simultaneously.

  After crystal growth at a constant temperature and constant pressure for a certain period of time, the temperature was lowered to room temperature and the plate template was taken out. As a result, a group III nitride single crystal could be grown on the plate template, and the plate template and group III nitride single crystal were grown. No cracks or cracks were observed in the crystal.

An alkali metal such as sodium has a large difference in specific gravity between a solid (970 kg / m ³ ) and a liquid (760 kg / m ³ , 800 ° C. (1073 K)) as large as 22%. For this reason, unless the plate template is installed in a state of being substantially perpendicular to the bottom surface of the crucible, stress is applied to the plate template at the time of taking out, that is, cooling, and thus the plate template is damaged. Further, since nitrogen is dissolved by pressurization from the gas-liquid interface, it is effective to reduce the concentration distribution in the vertical direction by installing the plate-like template in a substantially vertical state. Furthermore, a raw material liquid having a uniform concentration can be formed by performing the stirring direction parallel to the plate template. From the above, the method of installing the plate-like template in a state of being substantially vertical with respect to the bottom of the crucible is to dissolve the pressurized nitrogen in the raw material liquid composed of alkali metal and group III element, and in the raw material liquid III In the production method for growing a group nitride single crystal, the practical effect is great. In addition, the installation method of the said plate-shaped template is not an essential requirement of this invention, and it is arbitrary whether to implement.

(Embodiment 2)
In this embodiment, the hermetic pressure-resistant and heat-resistant container can be separated from the connection pipe, and only the hermetic pressure-resistant and heat-resistant container is swung. Hereinafter, an example of the manufacturing apparatus of this embodiment and an example of a manufacturing method using the same will be described.

  The manufacturing apparatus includes a raw material gas supply device for supplying a raw material gas, a pressure regulator for adjusting the pressure of the growth atmosphere, a hermetic pressure and heat resistant vessel for performing crystal growth, a heating device (growing furnace), and a hermetic seal Rotating mechanism for swinging the pressure resistant and heat resistant container. The hermetic pressure and heat resistant container is rotated by the rotating mechanism. When a crucible is inserted and fixed in the hermetic pressure-resistant and heat-resistant container, the crucible can be rotated simultaneously. In order to swing only the hermetic pressure-resistant and heat-resistant container, a rotation mechanism is attached to the connection pipe. For example, by periodically reversing the rotation direction, it is possible to stir the raw material liquid more efficiently. Improves nitrogen dissolution in the liquid. A compound single crystal can be produced in the same manner as in Embodiment 1 except that only the hermetic pressure and heat resistant container is swung. In a raw material liquid composed of a group III element and an alkali metal, for example, the material liquid is also stirred by friction with a crucible wall.

  As in this embodiment, in the stirring method in which the hermetic pressure-resistant and heat-resistant container is rotationally moved, the generation of non-uniform nuclei on the inner wall surface of the crucible can be suppressed as compared with the linear repetitive motion stirring method in the first embodiment. That is, in the linear repetitive motion stirring method of Embodiment 1, since the raw material liquid is not always in contact with the inner wall surface of the crucible, the reaction with the raw material gas such as nitrogen becomes intense, resulting in uneven nucleation. Will be promoted. On the other hand, in the stirring method of the rotational mobility as in this embodiment, since the raw material liquid is always in contact with the inner wall surface of the crucible, non-uniform nucleation can be suppressed. Further, in the production method of the present invention in which the source gas is dissolved in the source liquid from the gas-liquid interface, non-uniform nucleation is likely to occur at the gas-liquid interface. Therefore, it is necessary to stir the raw material liquid so that a flow is generated from the gas-liquid interface in contact with the raw material gas toward the inside of the raw material liquid. Three examples of the mechanism for this purpose are shown in FIG.

  In the mechanism shown in FIG. 11 (a), a crucible 1101 is covered with a lid 1102, and a stirring blade 1103 is hung from the lid 1102. Convection in the rotational direction is generated in the liquid 1104, and stirring is further promoted by the stirring blade 1103. At this time, the stirring blade 1103 causes a flow in the raw material liquid 1104 downward, that is, from the gas-liquid interface toward the inside of the raw material liquid.

  In the mechanism shown in FIG. 11B, a baffle plate 1106 is attached to the gas-liquid interface (the baffle plate 1106 may be integrated with the crucible 1101), and a hermetic pressure-resistant heat-resistant container (not shown). 1) and the crucible 1101 is rotated to cause a rotational convection in the raw material liquid 1104, the baffle plate 1106 generates a flow from the gas-liquid interface toward the inside of the raw material liquid 1104.

  In the mechanism shown in FIG. 11C, a spiral projection 1107 is formed on the inner wall surface of the crucible 1101, and the hermetic pressure-resistant and heat-resistant container (not shown) and the crucible 1101 are rotated to rotate into the raw material liquid 1104. When the convection occurs, the spiral projection 1107 causes a flow from the gas-liquid interface toward the inside of the raw material liquid 1104.

  As an apparatus for rotating the hermetic pressure-resistant and heat-resistant container, for example, an apparatus in which a rotation mechanism is attached to the above-described connection pipe is not limited to this. For example, in the lower part of the hermetic pressure-resistant and heat-resistant container, It is good also as an apparatus which attached the airtight pressure-proof heat-resistant container rotation mechanism. In this case, an auxiliary tank device for supplying source gas may be further attached to the hermetic pressure and heat resistant container. Moreover, you may attach the pressure regulator for adjusting a pressure to the intermediate part of the connection piping which connects the said airtight pressure-resistant heat-resistant container and auxiliary tank apparatus. The pressure of the auxiliary tank device is higher than the pressure of the hermetic pressure and heat resistant container. This makes it possible to replenish the raw material gas consumed in the hermetic pressure and heat resistant container.

(Embodiment 3)
In this embodiment, the source gas supply device and the hermetic pressure-resistant and heat-resistant container are connected by a flexible pipe, and the container is swung without separating the source gas supply device and the container. Hereinafter, an example of the manufacturing apparatus of this embodiment and an example of a manufacturing method using the same will be described.

  The manufacturing apparatus includes a raw material gas supply device for supplying a raw material gas, a pressure regulator for adjusting the pressure of the growth atmosphere, a hermetic pressure-resistant heat-resistant vessel for crystal growth, a flexible pipe, a heating device (a growth furnace) ) And a swinging device that swings the entire heating device (growing furnace). Since the raw material gas supply device and the hermetic pressure-resistant and heat-resistant container are connected by the flexible pipe, the whole heating device (growing furnace) is swung without detaching the hermetic pressure-resistant and heat-resistant container, The raw material liquid can be stirred. A compound single crystal can be produced in the same manner as in Embodiment 1 except that the hermetic pressure-resistant and heat-resistant container is swung without separating the source gas supply device and the hermetic pressure-resistant and heat-resistant container. In this case, since it is not necessary to separate the source gas supply device and the hermetic pressure-resistant and heat-resistant container, it is possible to stably perform crystal growth while keeping the pressure of the hermetic pressure-resistant and heat-resistant container constant by the pressure regulator, A certain growth direction and growth rate can be realized. As described above, the source gas supply device and the container may be separated, the container may be kept in a sealed state, and the container may be swung. Whether or not the source gas supply device and the container are separated is arbitrary. It is.

  In the first to third embodiments, it is preferable that the connecting pipe for supplying the source gas attached to the hermetic pressure-resistant and heat-resistant container is disposed outside the heating apparatus. This is because a stop valve, a pressure regulator, a flexible pipe, and the like need to be disposed outside the heating device. As described above, when the raw material liquid contains the alkali metal or alkaline earth metal, the vapor pressure increases at a high temperature of 700 ° C. (973 K) or higher. If distribution occurs, it will aggregate. Therefore, the temperature of the hermetic pressure and heat resistant container main body is preferably kept uniform. However, since the connecting pipe is disposed outside the heating device, if the inner diameter of the connecting pipe is too large, the vapor of the raw material liquid or the flux raw material is likely to move, and they aggregate in a low temperature region in the connecting pipe. It will solidify. As a result, the flux ratio in the raw material liquid changes, which greatly affects crystal growth. Further, if the connection pipe is clogged, it becomes impossible to supply nitrogen during the growth or supply nitrogen with a flexible pipe, which greatly affects crystal growth. When the inner diameter dependency of the connecting pipe for supplying the source gas attached to the hermetic pressure-resistant and heat-resistant container was evaluated, when the inner diameter was 3 mm or more, aggregation and coagulation were likely to occur in the connecting pipe, and when the inner diameter was 3 mm or less, aggregation occurred. It was found that agglomeration hardly occurred when the inner diameter was 2 mm or less. Therefore, the inner diameter of the connection pipe is preferably 3 mm or less, and more preferably 2 mm or less. In addition, it is preferable that the flexible pipe, the connection pipe of the container and the auxiliary tank device, and the like have the same inner diameter.

(Embodiment 4)
This embodiment is an example in the case of having a step of taking out the raw material liquid containing the flux raw material from the hermetic pressure and heat resistant container after the growth of the compound single crystal. In this invention, it is preferable to have the process of inject | pouring a flux raw material into a sealing pressure | voltage resistant heat resistant container, and the process of extracting the raw material liquid containing a flux raw material from a sealing pressure | voltage resistant heat resistant container after the production | generation of a compound single crystal. Note that this embodiment is not an essential requirement of the present invention, and whether or not it is implemented is arbitrary. Hereinafter, an example of the manufacturing method of this embodiment will be described.

  A flux raw material is injected into a crucible in a hermetic pressure-resistant and heat-resistant container into which a group III element has been inserted in advance by a flux raw material injection pipe. At that time, it is preferable to prevent oxidation of the flux material by replacing the atmosphere in the hermetic pressure-resistant and heat-resistant container with nitrogen. Thereafter, the inside of the hermetic pressure-resistant heat-resistant container is prepared in a pressurized atmosphere, heated to form a raw material liquid, and a single crystal is precipitated from the raw material liquid in which the raw material gas is in a supersaturated state.

  After the growth of the compound single crystal, the raw material liquid is taken out from the crucible in a state where the temperature in the heating apparatus (growing furnace) is set so that the raw material liquid does not solidify. The pressure of the hermetic pressure and heat resistant container is reduced, the extraction pipe is inserted into the raw material liquid, and the inside of the hermetic pressure and heat resistant container is pressurized, whereby the raw material liquid is taken out from the extraction pipe. In the case of a sodium and gallium raw material solution, for example, it is performed at 100 ° C. (373 K) or higher, preferably 300 ° C. (573 K) or higher, more preferably 500 ° C. (773 K) or higher.

  Thereby, it can avoid that the raw material liquid solidifies and shrinks at the time of cooling, and the formed single crystal is damaged. In addition, since alkali metals such as sodium react violently with water, it was necessary to treat with ethanol and so on, and it took time to take out the single crystal. Crystals can be easily taken out.

  Next, an example of the above process will be specifically described with reference to FIG.

  As shown in FIG. 7A, a group III element 701 and a template 702 as raw materials are inserted into the crucible 502. Next, as shown in FIG. 7B, a liquid flux material 703 is injected from the outside. Although not shown in the drawing, the injection pipe 504 is preferably wound with, for example, a microheater to keep the temperature of the injection pipe 504 at or above the melting point of the flux material.

  Next, as shown in FIG. 7 (c), the separation portion 505 is connected to a source gas supply device (not shown) in order to inject the source gas into the hermetic pressure and heat resistant container 501. The stop valve 503 is opened, and the source gas is supplied from the source gas supply device to the hermetic pressure and heat resistant container 501. The hermetic pressure-resistant and heat-resistant container 501 is fixed to a heating device (growing furnace) (not shown), and after raising the temperature to the growing temperature, pressure adjustment is performed. After the pressure adjustment, the stop valve 501 is closed, and the disconnection portion 505 is removed to disconnect.

  After the growth of the compound single crystal, the raw material liquid 506 is taken out from the crucible 502. The temperature of the raw material liquid 506 is lowered, the pressure in the hermetic pressure-resistant and heat-resistant container is reduced, the raw material liquid 506 is held in a molten state, and the extraction pipe 507 is inserted into the raw material liquid 506, Is extracted from the extraction pipe 507 into an external container (FIG. 7D).

  Except performing the process of inject | pouring a flux raw material into a sealing pressure | voltage resistant heat-resistant container, and the process of extracting the raw material liquid containing a flux raw material from a sealing pressure | voltage resistant heat-resistant container after the production | generation of a compound single crystal, it carries out similarly to Embodiment 1. A compound single crystal can be produced.

  In FIG. 1, the schematic block diagram of an example of the manufacturing apparatus of this invention is shown. A raw material gas supply device 101, a pressure regulator 102, a hermetic pressure and heat resistant vessel 103, a growth furnace 104, and a swinging device that swings the entire growth furnace 104 are provided. A stop valve 105 and a leak valve 106 are attached after the pressure regulator 102. A crucible 107 is set inside the hermetic pressure and heat resistant container 103. The connection pipe 114 for supplying the source gas and the hermetic pressure-resistant heat-resistant container 103 can be separated by the separation portion 108. A stop valve 109 is attached to the upper portion of the hermetic pressure and heat resistant container 103 via a connection portion 110. An electric furnace composed of a heat insulating material 111 and a heater 112 is disposed inside the growth furnace 104, and the temperature is controlled by a thermocouple 113. The hermetic pressure-resistant and heat-resistant container 103 is fixed in an electric furnace and can swing the entire growth furnace 104 in the direction of the arrow. In FIG. 1, reference numeral 115 denotes a connection pipe.

  In FIG. 3, the schematic block diagram of the other example of the manufacturing apparatus of this invention is shown. As shown in the figure, a crucible 306 is set inside a hermetic pressure and heat resistant container 305. A connection pipe (not shown) for supplying the source gas and the hermetic pressure and heat resistant container 305 can be separated by a separation portion 313. A stop valve 307 is attached to the upper portion of the hermetic pressure and heat resistant container 305 via a connection portion 308. Inside the growth furnace 309, an electric furnace composed of a heat insulating material 310 and a heater 311 is disposed, and the temperature is controlled by a thermocouple 312. A rotation mechanism 314 is attached to the connection pipe 315, and only the hermetic pressure and heat resistant container can be swung.

  In FIG. 12, the schematic block diagram of the further another example of the manufacturing apparatus of this invention is shown. In FIG. 12, the same parts as those in FIG. 3 except that the rotation mechanism 314 is attached to the connecting pipe 315, and the sealing pressure-resistant and heat-resistant container rotating mechanism 316 is attached to the lower part of the sealing pressure-resistant and heat-resistant container 305. is there.

  In FIG. 13, the schematic block diagram of the further another example of the manufacturing apparatus of this invention is shown. In FIG. 13, the same parts as those in FIG. Except that the auxiliary tank device 317 for supplying the raw material gas is attached to the hermetic pressure and heat resistant container 305 and that the pressure regulator 318 is attached via the connection portion 308 instead of the stop valve 307. This is the same as the apparatus of FIG.

  12 and FIG. 13, the lower part of the rotating shaft portion of the hermetic pressure-resistant and heat-resistant container rotating mechanism 316 is shaped like a gear as shown in FIG. 14, and the corrugated plate 318 is as shown by the upper arrow. By moving left and right, it is possible to convert a linear repetitive motion into a rotational motion whose direction of rotation changes as shown by the arrow below. FIG. 14 is a schematic view of the rotating shaft portion of the hermetic pressure and heat resistant container rotating mechanism 316 as viewed from below.

  In FIG. 4, the schematic block diagram of the further another example of the manufacturing apparatus of this invention is shown. A raw material gas supply device 405, a pressure regulator 407, a hermetic pressure and heat resistant container 401, a flexible pipe 408, a growth furnace 406, and a swinging device that swings the entire growth furnace 406 are provided. A stop valve 409 and a leak valve 410 are attached after the pressure regulator 407. A crucible 402 is set inside the hermetic pressure and heat resistant container 401. A stop valve 403 is attached to the upper portion of the hermetic pressure and heat resistant container 401 via a connection portion 404. An electric furnace composed of a heat insulating material 411 and a heater 412 is arranged inside the growth furnace 406, and the temperature is controlled by a thermocouple 413. Since the flexible pipe 408 is used to connect the hermetic pressure and heat resistant container 401 and the source gas supply device 405, the stop valve 403 may be opened or closed. When opened, the pressure in the hermetic pressure and heat resistant container 401 can be kept constant, so that stable growth is possible. The stop valve 403 may be closed when sufficient nitrogen is injected into the hermetic pressure and heat resistant container 401 for the consumption of the group III element. In this case, when the raw material gas supply device 405 is connected to a plurality of hermetic pressure-resistant and heat-resistant containers, even if a leak occurs, the other devices are not affected, so that a practical effect can be expected. . The hermetic pressure and heat resistant container 401 is fixed in an electric furnace, and the entire growth furnace 406 can be swung in the direction of the arrow. In the apparatus shown in FIG. 4, reference numeral 414 denotes a connection pipe.

  In FIG. 5, the schematic block diagram of the further another example of the manufacturing apparatus of this invention is shown. As shown in the figure, a crucible 502 is set inside a hermetic pressure and heat resistant container 501. An airtight pressure and heat resistant container 501 is provided with a flux raw material injection pipe 504 and an extraction pipe 506. A connection pipe (not shown) for supplying the source gas and the hermetic pressure-resistant heat-resistant container 501 can be separated by a separation portion 505. A stop valve 503 is attached to the top of the hermetic pressure vessel 501. An electric furnace composed of a heat insulating material 509 and a heater 510 is arranged inside the growth furnace 508, and the temperature is controlled by a thermocouple 511. The hermetic pressure-resistant and heat-resistant container 501 is fixed in an electric furnace and can swing the entire growth furnace 508 in the direction of the arrow.

A group III nitride single crystal was produced using the production apparatus of FIG. As a manufacturing method, the method shown in FIG. 2 was used. As the airtight pressure and heat resistant container 103, a stainless steel container made of SUS316 was used. Ga3g was used for the group III element 201, and Na3g was used for the alkali metal 202. The template 203 is heated to a sapphire substrate temperature of 1020 ° C. (1293 K) to 1100 ° C. (1373 K), and then trimethylgallium (TMG) and NH ₃ are supplied onto the substrate, whereby the sapphire substrate is made of GaN. A semiconductor layer formed of the above was used. The size of the template was 20 mm × 20 mm. The pressure regulator 102 in FIG. 1 was set to 25 atm (25 × 1.01325 × 10 ⁵ Pa), and the source gas was supplied from the source gas supply apparatus 101 to the stainless steel container 103. Nitrogen was used as the source gas. In this embodiment, since SUS316 is used as the material of the hermetic pressure and heat resistant container 103, the inside of the electric furnace is set to a nitrogen atmosphere. Therefore, even after the production of the single crystal, the hermetic pressure-resistant and heat-resistant container was hardly corroded and could be reused. The atmosphere gas may be other than nitrogen, and if it is an inert gas such as Ar, the corrosion of the hermetic pressure-resistant heat-resistant container can be reduced.

By raising the temperature to the growth temperature, a raw material solution was formed in the crucible, and the growth furnace 104 was swung in the direction of the arrow to produce a group III nitride semiconductor single crystal. The growth temperature was 850 ° C. (1123 K), and the nitrogen atmosphere pressure at 850 ° C. (1123 K) was 50 atm (50 × 1.01325 × 10 ⁵ Pa).

In order to prevent the nitrogen from being consumed and the pressure in the stainless steel container from decreasing, nitrogen was reinjected several times during the growth. Oscillation is temporarily stopped 10 hours after the start of the growth, the separation part 108 is connected to the raw material gas supply device 101, the raw material gas is injected into the stainless steel container 103, and the pressure in the stainless steel container 103 is set to 50 atm (50 × 1. 01325 × 10 ⁵ Pa). Thereafter, the separation part 108 was separated again, the swinging was resumed, and the breeding was continued.

  A single crystal having a thickness of 1 mm could be grown for a growth time of 30 hours. Since the crucible was swung and the raw material solution was stirred to dissolve nitrogen efficiently, the nitrogen dissolution time could be shortened within 10 hours, and a growth rate of 50 μm / hour could be realized.

  In the present embodiment, an example will be described in which the internal volume of the hermetic pressure-resistant and heat-resistant container is changed and the growth is continued while the hermetic pressure-resistant and heat-resistant container is disconnected from the source gas supply device.

First, using a hermetic pressure and heat resistant container having an internal volume V of 7.5 × 10 ⁻² (liter) and performing no group adjustment in the same manner as in Example 1 except that the pressure was not adjusted by supplementing nitrogen during the growth. A nitride single crystal was produced. The temperature T1 when Ga and Na were weighed was 27 ° C. (300 K). In this case, V × (P / 1.01235 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 2 (where V = 7.5 × 10 ⁻² (liter), T1 = 300 (K), gallium atomic weight a = 69.723, from Example 1, growth pressure P = 50 × 1.01235 × 10 ⁵ (Pa), growth temperature T = 1123 (K), consumption Gallium weight X = 3 (g)). Here, according to Boyle-Charle's law, the nitrogen volume (7.5 × 10 ⁻² liter) in the hermetic pressure-resistant heat-resistant container at the time of growth (50 atm, 1123 K) is converted to the volume at 1 atm and 300 K. Then, it becomes about 1 liter. Further, 1 atm, under 300K atmosphere, the nitrogen amount required to consume Ga3g (0.043 moles), from _{Ga + 1 / 2N 2 → GaN} , approximately 0.5 liters (22.4 × ( 0.043 / 2) × (300/273) = 0.53). Therefore, in the state where all of Ga3g has reacted, about 50% of nitrogen in the hermetic pressure-resistant and heat-resistant container is consumed, and the pressure at 850 ° C. (1123 K) in the hermetic pressure-resistant and heat-resistant container is 25 atmospheres (25 × 1. 01325 × 10 ⁵ Pa), and the pressure fluctuation is −50%. The pressure changed by 50% during the growth, and the growth rate decreased in the latter half of the growth period, but compared with the conventional method that does not stir the hermetic pressure and heat resistant vessel, uniform crystal growth and faster growth The rate was realized. Also, by reducing the size of the container, the device including the electric furnace could be made compact. However, when V × (P / 1.01235 × 10 ⁵ ) × (T1 / T) <(X / 2a) × 22.4 × 2, the pressure change during the growth is large, which is the same as the conventional growth method. Only the following growth rates were obtained.

Next, using a hermetic pressure-resistant and heat-resistant container having an internal volume V of 0.2 (liter) and performing no pressure adjustment by replenishing nitrogen during the growth, the group III nitride single substance was obtained in the same manner as in Example 1. Crystals were produced. The temperature T1 when Ga and Na were weighed was 27 ° C. (300 K). In this case, V × (P / 1.01235 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 5 (where V = 0.2 (liter), T1 = 300K, The atomic weight of gallium a = 69.723, from Example 1, the atmospheric pressure during growth P = 50 × 1.01235 × 10 ⁵ (Pa), the growth temperature T = 1123 K, the weight of gallium consumed X = 3 (g )). Here, according to Boyle-Charle's law, when the volume (0.2 liter) of nitrogen in the hermetic pressure-resistant heat-resistant container at the time of growth (50 atm, 1123 K) is converted to a volume at 1 atm, 300 K, about 2 .7 liters. In addition, as described above, the amount of nitrogen required to consume Ga3g (0.043 mol) in an atmosphere of 1 atm and 300 K is about 0.5 liter. Therefore, in the state where all of Ga3g has reacted, about 20% of nitrogen in the hermetic pressure-resistant and heat-resistant container is consumed, and the pressure at 850 ° C. (1123 K) in the hermetic pressure-resistant and heat-resistant container is 40 atmospheres (40 × 1. 01325 × 10 ⁵ Pa), and the pressure fluctuation is −20%. At 40 atmospheres at the end of growth and 50 atmospheres at the beginning of growth, the change in the amount of dissolved nitrogen was small, the change in the growth rate was also small, and uniform crystal growth could be realized. Naturally, when the growth is completed with 1.5 g of Ga consumption, the consumption of nitrogen is also halved, the pressure after the growth can be reduced to about 45 atm, and the pressure fluctuation during the growth is further increased. Since it can be made small, it is more preferable. (In this case, V × (P / 1.01235 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 10)

Next, using a hermetic pressure-resistant and heat-resistant container having an internal volume V of 0.4 (liter) and performing no pressure adjustment by replenishing nitrogen during the growth, a group III nitride single substance was obtained in the same manner as in Example 1. Crystals were produced. The temperature T1 when Ga and Na were weighed was 27 ° C. (300 K). In this case, V × (P / 1.01235 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 10 (where V = 0.4 (liter), T1 = 300K, The atomic weight of gallium a = 69.723, from Example 1, the atmospheric pressure during growth P = 50 × 1.01235 × 10 ⁵ (Pa), the growth temperature T = 1123 K, the weight of gallium consumed X = 3 (g )). Here, according to Boyle-Charle's law, when the volume (0.4 liter) of nitrogen in the hermetic pressure-resistant heat-resistant container at the time of growth (50 atm, 1123 K) is converted to the volume at 1 atm, 300 K, about 5 .3 liters. In addition, as described above, the amount of nitrogen required to consume Ga3g (0.043 mol) in an atmosphere of 1 atm and 300 K is about 0.5 liter. Therefore, in the state where all of Ga3g has reacted, about 10% of nitrogen in the hermetic pressure and heat resistant container is consumed, and the pressure at 850 ° C. (1123 K) in the hermetic pressure and heat resistant container is 45 atm (45 × 1.01325). × 10 ⁵ Pa) and the pressure fluctuation was −10%, and the change in the growth conditions could be further reduced.

Further, the sealed pressure-resistant heat-resistant container is set such that V × (P / 1.01235 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 10 with respect to Ga consumption. Even if the hermetic pressure-resistant and heat-resistant container and the raw material gas supply device are disconnected or the piping connecting them is closed to set the internal volume, pressure fluctuation during growth can be suppressed to about 10% and stable. Crystal growth was achieved.

A group III nitride single crystal was produced using the production apparatus of FIG. The manufacturing method used W (tungsten) crucible for crucible 306, Ga5g for group III element, Na5g and Li0.04g for alkali metal, and pressure regulator (not shown) at 10 atm ( 10 × 1.01325 × 10 ⁵ Pa), the raw material gas was supplied to the stainless steel container 305 from the raw material gas supply device (not shown), and the growth temperatures were 830 ° C. (1103 K) and 830 ° C. (1103 K). The same procedure as in Example 1 was conducted except that the nitrogen atmosphere pressure at 20 atm was 20 atm (20 × 1.01325 × 10 ⁵ Pa). In this embodiment, only the stainless steel container 305 is swung by the rotation mechanism 314 attached to the connection pipe 315.

  A 2 mm thick crystal could be grown for a growth time of 40 hours. As a growth rate, high-speed growth of 60 to 70 μm / hour could be realized.

  Note that the stainless steel container 305 can be rotated more stably by using the manufacturing apparatus of FIG. 12 instead of the manufacturing apparatus of FIG. Because it was possible to fix firmly, it was easy to perform the reversal movement. Further, by using the manufacturing apparatus of FIG. 13 instead of the manufacturing apparatus of FIG. 3, it is possible to replenish the raw material gas consumed in the hermetic pressure and heat resistant container.

  In this embodiment, since the pressurized source gas is dissolved in the source liquid, non-uniform nucleation is likely to occur at the gas-liquid interface. The purpose of the stirring of the present invention is to stir the raw material liquid so that a flow is generated from the gas-liquid interface in contact with the raw material gas toward the inside of the raw material liquid. In order to efficiently stir the raw material liquid based on the rotational mobility, it is preferable to attach a mechanism for generating a flow toward the inside of the raw material liquid in the container that holds the raw material liquid, that is, the crucible.

  Therefore, for example, by further attaching the three mechanisms shown in FIG. 11 to the crucible, a flow from the gas-liquid interface toward the inside of the raw material liquid could be formed. This makes it possible to suppress non-uniform nucleation at the gas-liquid interface.

Specifically, in a manufacturing apparatus that does not have the above mechanism, non-uniform nucleation occurs at the gas-liquid interface and the inner wall surface of the crucible under the growth conditions of 850 ° C. and 50 atm (50 × 1.01325 × 10 ⁵ Pa). On the other hand, by providing the three mechanisms shown in FIG. 11, non-uniform nucleation does not occur even under growth conditions of 850 ° C. and 50 atm (50 × 1.01325 × 10 ⁵ Pa), and 50 μm / hour. The above growth rate was obtained.

A group III nitride single crystal was produced using the production apparatus of FIG. The manufacturing method is the use of an Inconel container for the hermetic pressure-resistant and heat-resistant container 401, an alumina crucible for the crucible 402, Ga5g for the group III element, Na5g for the alkali metal, and an alkaline earth metal. The use of Ca 0.05 g, the use of a template having a GaN semiconductor layer having a thickness of 10 μm on the sapphire substrate, and the nitrogen atmosphere pressure at a growth temperature of 850 ° C. (1123 K) and 850 ° C. (1123 K) are 20 It was the same as that of Example 1 except having set it as atmospheric | air pressure (20 * 1.01325 * 10 < ⁵ > Pa). In this embodiment, the Inconel container 401 and the source gas supply device 405 are connected by a connecting portion 404 using a flexible pipe 408, and the flexible pipe 408 is also 1000 atm (1000 × 1.01325 × 10 ⁵ Pa). Because of the corresponding design, it was possible to grow the Inconel container 401 while swinging without disconnecting the Inconel container 401 and the source gas supply device 405 at the connection portion 404.

  A 2 mm thick crystal could be grown for a growth time of 30 hours. Since the crucible was swung and the raw material solution was stirred to dissolve nitrogen efficiently, the nitrogen dissolution time could be shortened within 10 hours, and the growth rate could be about 100 μm / hour. In this example, since Inconel was used as the material of the hermetic pressure-resistant and heat-resistant container, the atmosphere in the electric furnace was air, but almost no corrosion of the hermetic pressure-resistant and heat-resistant container was observed. In addition, Preferably, the frequency | count of reuse of a hermetic pressure | voltage resistant heat-resistant container can be improved by making the atmosphere in an electric furnace into inert gas. Corrosion was hardly observed even when Hastelloy or Incoloy was used as an alternative material for the hermetic pressure and heat resistant container and the atmosphere in the electric furnace was similarly air.

  A group III nitride single crystal was produced using the production apparatus of FIG. As a manufacturing method, the method shown in FIG. 7 was used. A stainless steel container was used as the hermetic pressure and heat resistant container 501. Ga was used for the group III element 701, a template having a semiconductor layer represented by AlN on a sapphire substrate was used for the template 702, and liquid sodium was used for the flux material 703.

  Next, the raw material liquid was formed in the crucible by raising the temperature to the growth temperature, and the growth furnace 508 was swung in the direction of the arrow to produce a group III nitride semiconductor single crystal. After the growth of the single crystal, the temperature of the raw material liquid is lowered to 300 ° C. (573 K), and the raw material liquid is extracted to avoid the alloying of the raw material liquid during cooling and damaging the formed single crystal. I was able to.

  A group III nitride single crystal was produced using the production apparatus of FIG. As a manufacturing method, the method shown in FIG. 10 was used. A stainless steel container was used as the hermetic pressure and heat resistant container 401, and an alumina crucible was used as the crucible 402 (1001). 40 g of Ga was used for the Group III element, and 50 g of Na was used for the alkali metal. As the template 1003, a template having a GaN semiconductor layer having a thickness of 10 μm on a sapphire substrate was used. As shown in FIG. 10A, the five templates 1003 were installed perpendicular to the bottom surface of the crucible 1001.

Next, the raw material liquid was formed in the crucible by raising the temperature to the growth temperature, and the growth furnace 406 was swung in the direction of the arrow to produce a group III nitride semiconductor single crystal. The growth temperature was 850 ° C. (1123 K), and the nitrogen atmosphere pressure at 850 ° C. (1123 K) was 35 atm (35 × 1.01325 × 10 ⁵ Pa).

  After growing at constant temperature and constant pressure for 50 hours, the temperature was lowered to room temperature and the template was taken out. As a result, a 2 mm thick GaN single crystal could be grown on the template, and cracks and cracks were observed on the template and GaN single crystal. There wasn't.

  As described above, according to the present invention, the stirring of the raw material liquid is facilitated, the dissolution of nitrogen is promoted, and a high-quality and low-cost substrate can be provided.

It is a schematic diagram which shows an example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows an example of the process of the manufacturing method of this invention. It is a schematic diagram which shows the other example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows the further another example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows the further another example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows an example of the stirring process of the raw material liquid of this invention. It is a schematic diagram which shows the other example of the process of the manufacturing method of this invention. It is a schematic diagram which shows an example of a structure of the conventional manufacturing apparatus. It is a schematic diagram which shows an example of the process of the conventional manufacturing method. It is a schematic diagram which shows the further another example of the process of the manufacturing method of this invention. It is a schematic diagram which shows the example of the mechanism for stirring of the raw material liquid of this invention. It is a schematic diagram which shows the further another example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows the further another example of a structure of the manufacturing apparatus of this invention. It is a schematic diagram which shows an example of a structure of the airtight pressure | voltage resistant heat-resistant container rotation mechanism of this invention.

Explanation of symbols

101, 405, 801 Source gas supply devices 102, 318, 407, 802 Pressure regulators 103, 305, 401, 501, 803 Sealing pressure and heat resistant containers 104, 309, 406, 508, 804 Growth furnaces 105, 109, 307, 403, 409, 503, 807 Stop valve 106, 410, 808 Leak valve 107, 306, 402, 502, 601, 805, 901, 1001, 1101 Crucible 108, 313, 505 Disconnection part 110, 308, 404 Connection part 111, 310, 411, 509 Heat insulating material 112, 311, 412, 510 Heater 113, 312, 413, 511 Thermocouple 114, 806 Connection pipe 115, 205, 315, 414 Connection pipe 201, 701 Group III element 202 Alkali metal 203, 603 , 702, 90 2, 1003, 1105 Template 204 Upper lid 314 Rotating mechanism 316 Sealing pressure and heat resistant container rotating mechanism 317 Auxiliary tank device 318 Corrugated plate 408 Flexible pipe 504 Injection pipe 506, 602, 903, 1002, 1104 Raw material liquid 507 Extraction pipe 703 Flux Raw material 1102 Lid 1103 Stir blade 1106 Baffle plate 1107 Spiral projection

Claims (42)

A method for producing a compound single crystal, in which a raw material gas and a raw material liquid are reacted to grow a compound single crystal, wherein the flow of the raw material liquid from the gas-liquid interface in contact with the raw material gas toward the inside of the raw material liquid A production method characterized in that the single crystal is grown while stirring the raw material solution so as to occur. A single crystal manufacturing apparatus having a heating device and a hermetic pressure-resistant heat-resistant container that heats inside the heating device is prepared, and the compound single crystal source gas and other raw materials are placed in the container under a pressurized atmosphere. The container is housed in the heating device, the container is heated by the heating device to make the other raw materials liquid, and a raw material liquid is prepared. In this state, the raw material gas is stirred while stirring the raw material liquid The manufacturing method according to claim 1, wherein a single crystal is grown by reacting the raw material liquid with the raw material liquid. The manufacturing method according to claim 2, wherein the single crystal is grown by reacting the raw material gas and the raw material liquid while stirring the raw material liquid by swinging the container. The manufacturing method according to claim 3, wherein the container is also rocked by rocking the heating device. A crucible is installed in the container, and at least one of the inside of the crucible and the inner wall surface has at least one selected from the group consisting of the following (A), (B), (C) and (D). The manufacturing method according to claim 2, wherein:
(A) Stirrer blade (B) Baffle plate (C) Template (D) Spiral protrusion The said rocking | fluctuation is at least 1 motion selected from the group which consists of a moving motion, a linear repetitive motion, a pendulum-like repetitive motion, a rotational motion, and these combined motion. Production method. The manufacturing method according to claim 2, wherein the other raw material includes a flux raw material. The single crystal manufacturing apparatus further includes a raw material gas supply device, connects the raw material gas supply device to the container in which the other raw materials are placed, supplies the raw material gas, and after the supply ends, from the container The manufacturing method of Claim 3 or 4 which cut | disconnects the said raw material gas supply apparatus, and rocks the said container after that. The manufacturing method according to claim 8, wherein the raw material gas supply device is separated from the container after the container is heated to liquefy the other raw materials and adjust the pressure in the container. The manufacturing method according to claim 2, wherein the pressure of the source gas in the container after the generation of the single crystal is reduced. The manufacturing method according to claim 2, wherein the single crystal manufacturing apparatus further includes an auxiliary tank device for supplying a source gas, and the auxiliary tank device and the container are connected. The single crystal manufacturing apparatus further includes a raw material gas supply device, the raw material gas supply device and the container are connected by a flexible pipe, and the container is disposed without separating the raw material gas supply device and the container. The manufacturing method of Claim 3 which rocks. The source gas contains at least one of nitrogen and ammonia, and the other source material includes at least one group III element selected from the group consisting of gallium, aluminum, and indium and a flux source, in the source solution The production method according to any one of claims 1 to 12, wherein the produced single crystal is a group III nitride single crystal. The manufacturing method according to claim 13, wherein the flux material contains at least one of an alkali metal and an alkaline earth metal. A template having a semiconductor layer represented by a composition formula Al _u Ga _v In _1-uv N (where 0 ≦ u ≦ 1, 0 ≦ v ≦ 1, 0 ≦ u + v ≦ 1) is placed in the container in advance. The manufacturing method according to claim 13. The manufacturing method according to claim 15, wherein the immersion of the template in the other raw material liquid is performed in the container after the raw material liquid is formed by heating and the raw material gas is dissolved in the raw material liquid. The manufacturing method according to claim 15 or 16, wherein a crucible is installed in the container, and the template is a plate-like template, and is installed in a state of being substantially perpendicular to a bottom surface of the crucible. 18. The manufacturing method according to claim 17, wherein the container is swung so that the raw material liquid moves in a direction parallel to the plate template. The manufacturing method of Claim 7 which takes out at least the said flux raw material from the said container after completion | finish of the growth of a compound single crystal. The manufacturing method according to claim 19, wherein the other raw material liquid contains at least gallium and sodium, and a heating temperature thereof is 100 ° C. (373 K) or more. The manufacturing method according to claim 20, wherein the heating temperature is 300 ° C (573K) or more instead of 100 ° C (373K). The manufacturing method according to claim 20, wherein the heating temperature is 500 ° C (773K) or more instead of 100 ° C (373K). The method according to claim 13, wherein the growth rate of the group III nitride single crystal is 30 μm / hour or more. The manufacturing method according to claim 13, wherein the growth rate of the group III nitride single crystal is 50 μm / hour or more. The manufacturing method according to claim 13, wherein the growth rate of the group III nitride single crystal is 100 μm / hour or more. The manufacturing method according to claim 2, wherein the pressure of the source gas in the container is 5 atm (5 × 1.01325 × 10 ⁵ Pa) or more and 1000 atm (1000 × 1.01325 × 10 ⁵ Pa) or less. The manufacturing method of Claim 2 with which the inert gas is filled in the said heating apparatus. In the case where gallium is contained in the other raw materials, the internal volume of the container is increased to V (liter) with respect to the weight X (g) of the gallium consumed and the atomic weight a (= 69.723) ( Claims that satisfy the following formula (1), where P (Pa) is the atmospheric pressure during the production of the single crystal, T (K) is the growth temperature, and T1 (K) is the temperature at which the other raw materials are weighed. Item 3. The production method according to Item 2.
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 2 (1) The manufacturing method according to claim 28, wherein the following formula (2) is satisfied instead of the formula (1).
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 5 (2) The manufacturing method according to claim 28, wherein the following formula (3) is satisfied instead of the formula (1).
V × (P / 1.01325 × 10 ⁵ ) × (T1 / T)> (X / 2a) × 22.4 × 10 (3) The said single crystal manufacturing apparatus WHEREIN: The piping which connects the said container accommodated in the said heating apparatus and the said heating apparatus exterior is a structure which is hard to aggregate at least one of the said raw material liquid and the said other raw material. Production method. 32. The method for producing a single crystal according to claim 31, wherein the inner diameter of the pipe is 3 mm or less. 32. The method for producing a single crystal according to claim 31, wherein an inner diameter of the pipe is 2 mm or less. 3. The single crystal manufacturing apparatus used in the manufacturing method according to claim 2, wherein the hermetic pressure-resistant and heat-resistant container, a heating apparatus that houses the container therein, and a rocking device that rocks the container. Including single crystal manufacturing equipment. 35. The single crystal manufacturing apparatus according to claim 34, wherein the container swings together with the heating apparatus. 36. The manufacturing apparatus according to claim 34 or 35, wherein the oscillation is at least one movement selected from the group consisting of a movement movement, a linear repetitive movement, a pendulum repetitive movement, a rotational movement, and a combination movement thereof. A crucible is installed in the container, and at least one of the inside of the crucible and the inner wall surface has at least one selected from the group consisting of the following (A), (B), (C) and (D). The single crystal manufacturing apparatus according to any one of claims 34 to 36.
(A) Stirrer blade (B) Baffle plate (C) Template (D) Spiral protrusion The single crystal manufacturing apparatus according to any one of claims 34 to 37, wherein the container is accommodated in the heating device so as to be maintained at a constant temperature. The single crystal manufacturing apparatus according to any one of claims 34 to 37, further comprising a source gas supply apparatus. 40. The single crystal manufacturing apparatus according to claim 39, wherein the container and the source gas supply apparatus are freely connectable and disconnectable. 40. The single crystal manufacturing apparatus according to claim 39, further comprising a flexible pipe, whereby the container and the source gas supply apparatus are connected. The single crystal manufacturing apparatus according to any one of claims 34 to 37, further comprising an auxiliary tank device for supplying source gas, wherein the auxiliary tank device is connected to the container.

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