JP6885205B2 - Metal steam supply equipment, metal / metal compound production equipment, metal nitride single crystal production method, and nanoparticles production method - Google Patents

Description

The present invention relates to a metal steam supply device, a metal / metal compound production device, a method for producing a metal nitride single crystal, and a method for producing nanoparticles. More specifically, the present invention can supply metal steam at a high supply rate. The present invention relates to a metal steam supply device, a metal / metal compound manufacturing device using the metal steam supply device, a method for manufacturing a metal nitride single crystal, and a method for manufacturing nanoparticles.

As one of the methods for synthesizing thin films, single crystals, or nanoparticles, a method of vaporizing a liquid raw material and thermally decomposing the generated vapor of the raw material to generate a desired material on the substrate surface or in the gas phase is known. Has been done. Such a material synthesis method using a gas phase has an advantage that the film thickness, material composition, crystal structure, etc. can be precisely controlled, but the supply rate of the raw material vapor is often rate-determining. Therefore, in order to solve this problem, various proposals have been made conventionally.

For example, Patent Document 1 describes a method of evaporating a liquid raw material (tri (dimethylamino) cyclopentadienyl zirconium) for forming a zirconium oxide film on a semiconductor wafer, which is a stainless steel having a thickness of about 20 μm. A method is disclosed in which one end of a fiber body in which stainless steel fibers are three-dimensionally combined is brought into contact with a liquid raw material.
According to the document, the liquid raw material is sucked up by the fibrous body due to the capillary phenomenon, and the liquid raw material is vaporized not only from the liquid surface but also from the fibrous body surface. It is described that the amount of vaporization of can be increased.

Further, when growing a GaN crystal, a method of using _{gallium hydride (GaH x) as a Ga source is known.} In order to improve the crystal growth rate, it is necessary to improve the supply rate of gallium hydride, that is, _{to efficiently react Ga and H 2.} In order to solve this problem, Non-Patent Document 1 discloses a method of filling a ceramic tube with ceramic beads whose surface is covered with liquid Ga _{and supplying H 2 into the tube.}
The document describes that such a method _{narrows the flow path of H 2} and at the same time increases the surface area of the liquid Ga, so that the reaction efficiency increases.

Further, Patent Document 2 discloses a metal steam supply device that generates Ga steam using an evaporator manufactured by TaC.
In the same document,
(A) The TaC evaporator has a higher crawling height of molten Ga than an evaporator composed of _{SiC, Al 2} O _{3, BN, or C, and}
(B) It is described that when the TaC evaporator is used, the supply rate of Ga steam is increased as compared with the case where the evaporator is not used.

In the case of the method described in Patent Document 1, a liquid metal compound is used as a raw material for vaporization, and a stainless steel fiber body is used as an evaporator for promoting vaporization. Since the liquid metal compound is an organic substance and has a small surface tension, the contact angle tends to be small, and the liquid metal compound easily gets wet with the fibrous body. Therefore, a sufficient amount of capillarity can occur without considering the material, surface condition, capillary diameter, relative density, and the like of the fibrous body. In fact, Patent Document 1 does not describe the optimum capillary diameter, relative density, and the like.

On the other hand, when the raw material to be vaporized is a molten metal, the surface tension is much larger than that of the liquid metal compound, so that the contact angle tends to be close to 90 ° and it is difficult to get wet with other materials. Therefore, it is difficult for the molten metal to cause a sufficient amount of capillarity. Further, since the stainless steel wire is inferior in heat resistance at 500 ° C. or higher, the stainless steel fiber body cannot be used in a temperature range exceeding 500 ° C.

Further, since the liquid metal compound is an organic substance having low thermal stability, the higher the heating temperature, the easier it is to decompose. Unintentional decomposition of liquid metal compounds causes impurities derived from organic substances such as C (carbon), H (hydrogen), and N (nitrogen) to be mixed into the product. Therefore, when vaporizing a liquid organometallic compound, there is a limit to the rate of vaporization that can be reached.
In the case of molten metals, low thermal stability is less of a problem, but metals generally have extremely low vapor pressures. Therefore, even in the vaporization of molten metal, there is a limit to the reachable vaporization rate.

In the case of the method described in Non-Patent Document 1, since the surface of the ceramic beads is covered with liquid Ga, the surface area of Ga increases and the reaction with hydrogen proceeds efficiently. However, although the method of the same document has the effect of improving the surface area at the initial stage of the reaction, the vaporization rate gradually decreases as Ga evaporates. As a result, the supply amount of Ga (that is, gallium hydride) fluctuates during the reaction process, and there is a problem that the controllability of the raw material supply, which is essential for high-quality crystal growth, is poor.

On the other hand, as described in Patent Document 2, when the TaC evaporator is used, Ga steam can be supplied at a high supply rate, and the supply rate is controlled to be substantially constant over a long period of time. It becomes possible to do. However, there has been no conventional example in which a metal vapor supply device capable of supplying metal vapor other than Ga at a high supply rate has been proposed.
Further, in order to further improve the growth rate of the thin film, the single crystal, or the nanoparticles, or to reduce the manufacturing cost of the thin film, the supply rate of the metal steam is further improved, or the cost is lower than that of TaC. It is desired to achieve a higher supply rate with a flexible material.

Japanese Patent No. 5589873 Japanese Unexamined Patent Publication No. 2016-157886

M. Imade et al., Physica Status Solidi (c), Colume 5, Issure 6, pp. 1719-1722, 2008

The problem to be solved by the present invention is to provide a metal vapor supply device capable of supplying metal vapor at a high supply rate and controlling the supply rate to be substantially constant over a long period of time. To do.
Another problem to be solved by the present invention is a metal / metal compound manufacturing apparatus for producing a single crystal, nanoparticles, a thin film or the like made of a metal or a compound thereof by using such a metal steam supply apparatus. To provide.

Another object to be solved by the present invention is to provide a method for producing a metal nitride single crystal using such a metal / metal compound production apparatus, and a method for producing nanoparticles.
Further, another problem to be solved by the present invention is not only Ga but also a metal steam supply device capable of supplying metal steam other than Ga at a high supply rate, and such a metal steam supply device. It is an object of the present invention to provide a metal / metal compound production apparatus used, a method for producing a metal nitride single crystal, and a method for producing nanoparticles.

In order to solve the above problems, it is a gist that the first metal steam supply device according to the present invention has the following configuration.
(1) The metal steam supply device is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
(2) The evaporator is
Relative density is 40% or more and 99% or less,
The average pore diameter is 10 nm or more and 200 μm or less, and
It is made of a material having a contact angle of the molten metal of less than 90 °.
(3) the material of the evaporator, TiC, VC, ZrC, NbC , Mo 2 C, WC, HfC, TiN, TaN, ZrN, or made of HfN.
The molten metal is preferably any one or more elements selected from the group consisting of Ga, In, and Al.

The first metal / compound production apparatus according to the present invention is
The first metal steam supply device according to the present invention and
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
The gist is that the surface is provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited.

In the method for producing a first metal nitride single crystal according to the present invention, the metal vapor is generated in the presence of a nitride gas using the first metal / metal compound production apparatus according to the present invention, and the metal vapor is generated on the substrate. The gist is to grow a metal nitride single crystal.
Further, in the method for producing the first nanoparticles according to the present invention, the metal vapor is generated in the presence of an inert gas or an active gas by using the first metal / metal compound producing apparatus according to the present invention. The gist is to deposit metal nanoparticles or metal compound nanoparticles on a substrate.

The gist of the second metal steam supply device according to the present invention is that it has the following configuration.
(1) The metal steam supply device is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
(2) The evaporator is
Relative density is 40% or more and 99% or less,
The average pore diameter is 10 nm or more and 200 μm or less, and
It is made of a material having a contact angle of the molten metal of less than 90 °.
(3) The material of the evaporator is made of TaC.
The molten metal is
(A) In and / or Al, or
(B) Ga and In and / or Al
Consists of.

The second metal / compound production apparatus according to the present invention is
The second metal steam supply device according to the present invention and
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
The gist is that the surface is provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited.

In the method for producing a second metal nitride single crystal according to the present invention, the metal vapor is generated in the presence of a nitride gas using the second metal / metal compound production apparatus according to the present invention, and the metal vapor is generated on the substrate. The gist is to grow a metal nitride single crystal.
Further, in the method for producing the second nanoparticles according to the present invention, the metal vapor is generated in the presence of an inert gas or an active gas by using the second metal / metal compound producing apparatus according to the present invention. The gist is to deposit metal nanoparticles or metal compound nanoparticles on a substrate.

When a part of the evaporator is brought into contact with the molten metal, the molten metal crawls up the surface of the evaporator, and the surface of the evaporator gets wet with the molten metal. When the surface of the evaporator gets wet with the molten metal, the apparent surface area of the molten metal increases. As a result, the supply rate of the metal vapor is increased as compared with the case where the evaporator is not used.
In particular, by optimizing the average pore diameter, relative density, material, etc. of the evaporator, the supply rate of metal vapor can be increased from several times to several tens of times that of the conventional one. When such a metal steam supply device is applied to the growth of a metal nitride single crystal such as GaN, the growth rate of the metal nitride single crystal can be improved by about 3 to 5 times or more as compared with the conventional method. it can.

Furthermore, specific transition metal carbides such as TiC and VC and specific transition metal nitrides such as TiN and TaN exhibit wettability equal to or higher than that of TaC with respect to certain molten metals. Further, these transition metal carbides or transition metal nitrides are cheaper than TaC. Therefore, when these are used as the material of the evaporator, the growth rate of the thin film or the like can be further improved, or the manufacturing cost of the thin film or the like can be reduced.

It is a schematic diagram of the structural example of an evaporator. It is a figure which shows the relative density dependence of the crawling height of molten Ga with respect to WC. It is a figure which shows the average pore diameter dependence of the crawling height of molten Ga with respect to WC.

It is a figure which shows the relationship between the area ratio (= deemed surface area / molten metal area) of the WC evaporator, and the growth rate of GaN. It is a figure which shows the evaporator material dependence of the creeping height of molten Ga. It is a figure which shows the evaporator material dependence of the creeping height of molten In. It is a figure which shows the evaporator material dependence of the creeping height of molten Al.

Hereinafter, an embodiment of the present invention will be described in detail.
[1. Metal steam supply device (1)]
The metal steam supply device according to the first embodiment of the present invention is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
The metal vapor supply device may further include a carrier gas supply unit that supplies carrier gas into the crucible.

[1.1. metal]
In the present invention, the type of metal is not particularly limited, and the present invention can be applied to any metal as long as vaporization is possible.
Among them, Ga, In and Al are mentioned as particularly useful metal elements. GaN, which is a nitride of Ga, is a wide bandgap semiconductor, and its application to LED lighting and the like is progressing. In addition, various industrial applications such as blue lasers, power devices, and high frequency devices are expected in the future. Further, InN and AlN are also expected to be applied to high frequency devices and deep ultraviolet devices in the future. Further, in the case of application, these mixed crystals such as InGaN, AlGaN, InAlN, and InAlGaN are also used. Therefore, the present invention is applicable to the growth of these crystals.

On the other hand, since the vapor pressure of Ga is as small as about 0.5 Pa even in a high temperature region of 1000 ° C., Ga vapor is not usually used for the growth of GaN. Currently, as a method for obtaining high-quality GaN thin film crystals, an organometallic vapor phase growth method using an organometallic such as trimethylgallium as a Ga source is known (Reference 1). However, it is difficult to use trimethylgallium as a Ga source for growing a bulk GaN crystal because of its high reactivity and high cost.
[Reference 1] H. Amano et al., APL. 48, 353, 1986

Further, a method of supplying gallium as gallium chloride using HCl gas and reacting it with ammonia is called an HVPE (Hydride Vapor Phase Epitaxy) method, and has been reported as a method for producing bulk GaN crystals. However, when gallium chloride is used, there is a problem that ammonium chloride, which is a by-product, is clogged in pipes and the like (Reference 2).
On the other hand, the present invention can directly supply a relatively large amount of Ga vapor to the surface of the seed crystal. Therefore, if this is applied to the growth of a GaN single crystal, it is possible to grow a bulk GaN crystal that is easy to handle, does not contain impurities, and is low in cost.
[Reference 2] Japanese Unexamined Patent Publication No. 2007-201147

For the growth of InN, a method called the HVPE method is currently being studied as in the case of GaN. However, since a halide is used as in the case of GaN, there is a problem that the piping is clogged by by-products and impurities are easily mixed. On the other hand, if the present invention is used, there is a possibility that a high quality InN single crystal with less contamination can be produced.
Currently, a method called sublimation method is used for the growth of AlN. This is a method of sublimating polycrystalline AlN at a high temperature _{and reacting the sublimation gas with N 2} to grow single crystal AlN. However, in the sublimation method, the influence of impurities derived from raw materials is large. On the other hand, if the present invention is used, there is a possibility that a higher quality AlN single crystal can be produced.

[1.2. Crucible]
The crucible is for holding the molten metal. When generating a plurality of types of metal vapor from a metal vapor supply device at the same time, a plurality of crucibles are installed in the device, and different metals are accommodated in each crucible. The shape of the crucible may be any shape as long as it can hold a predetermined amount of molten metal and the evaporator can be arranged in the crucible so that a part of the evaporator comes into contact with the molten metal.
The material of the crucible may be one that does not react with the molten metal. The optimum crucible material depends on the type of molten metal. For example, when the metal is Ga, the material of the crucible is preferably BN, TaC, carbon, SiC, sapphire, platinum or the like. The same applies when the metal is In or Al, and it is preferable to select the optimum material from these crucible materials.

[1.3. Evaporator]
The evaporator is for promoting the generation of metal vapor. The evaporator is installed in the crucible so that a part of it can come into contact with the molten metal.
The evaporator may be fixed to any part of the crucible, or may be simply placed on the bottom surface of the crucible. When the evaporator is not fixed to the crucible and the specific gravity of the evaporator is smaller than the specific density of the molten metal, the evaporator is in a state of floating on the surface of the molten metal. Even in such a state, the generation of metal vapor can be promoted by the evaporator.

[13.1. Evaporator material]
In order to generate metal vapor using an evaporator, the material of the evaporator needs to have at least a high melting point and low reactivity with molten metal. Examples of the material of the evaporator include metal oxides, metal carbides, metal borides, metal nitrides, carbon-based materials and the like.

In this embodiment, the material of the evaporator, TiC, VC, ZrC, NbC , Mo 2 C, WC, HfC, TiN, TaN, ZrN, or made of HfN. This point is different from the conventional one. The material of the evaporator may consist of any one of these, or may be a mixture of two or more or a solid solution.
Both of these particular transition metal carbides and transition metal nitrides are
(A) High melting point,
(B) At least the wettability to molten Ga, molten In, and molten Al is good, and the creeping height thereof is equal to or higher than that of TaC, so that metal steam can be supplied more efficiently.
(C) It is cheaper than TaC and it is easy to manufacture an evaporator.
There are advantages such as.

[1.3.2. Evaporator melting point]
The molten metal has a saturated vapor pressure depending on the material and temperature. In general, the saturated vapor pressure increases as the temperature rises, so it is more efficient to use the evaporator in a higher temperature range in order to promote the generation of metal vapor. However, if the melting point of the evaporator is lower than the operating temperature, the shape of the evaporator cannot be maintained, and it becomes difficult to supply metal vapor. Therefore, the melting point of the evaporator material is preferably higher than the operating temperature. The melting point of the material of the evaporator is more preferably the operating temperature + 100 ° C. or higher.
Specifically, the melting point of the material of the evaporator is preferably 1500 ° C. or higher, 2000 ° C. or higher, 2500 ° C. or higher, or 3000 ° C. or higher. The above-mentioned TiC and the like are all high melting point compounds and are suitable as materials for the evaporator.

[1.3.3. Evaporator Relative Density, Average Pore Diameter, and Contact Angle]
In order to promote the generation of metal vapor using the evaporator, it is necessary to cause a capillary phenomenon on the surface of the evaporator and to wet the surface of the evaporator with molten metal as much as possible. For that purpose, the relative density of the evaporator, the average pore diameter (inner diameter of the capillary tube), and the contact angle with the molten metal are important.

When a part of the evaporator is brought into contact with the molten metal, the molten metal crawls up the surface of the evaporator, and the surface of the evaporator gets wet with the molten metal. The height (crawling height) h from the lower end of the evaporator to the tip of the molten metal at this time is expressed by the following equation (1).
h = 2γ _L cos θ / ρgr
= 2γ _L cos θ / {ρg (1- (R / 100) ^1/3 ) AC} ・ ・ ・ (1)
However,
h: Crawling height, ρ: Density of molten metal, g: Gravitational acceleration, r: Inner diameter of capillary tube,
γ _L : Surface tension of molten metal, θ: Contact angle, R: Relative density of evaporator,
A: Average crystal particle size of the evaporator, C: Pore density correction coefficient.

[A. Relative density]
From equation (1), it can be seen that the smaller the relative density R of the evaporator, the smaller the climbing height h. This is because the smaller the relative density R, the larger the inner diameter r of the capillary tube. Further, when the relative density R is small, a decrease in strength is also an issue. Therefore, in order to increase the crawling height h, the relative density R of the evaporator is preferably 40% or more. The relative density R is more preferably 60% or more, still more preferably 80% or more.

On the other hand, according to the equation (1), the larger the relative density R, the larger the crawling height h. However, in reality, when the relative density R becomes excessively large, the open pores do not exist, and it becomes difficult to cause a capillary phenomenon on the surface of the evaporator. Therefore, the relative density R is preferably 99% or less. The relative density R is more preferably 98% or less, still more preferably 97% or less.

[B. Average pore size]
Similarly, there is an optimum region for the average pore size. In order to cause the capillary phenomenon, it is necessary to establish a continuum approximation of molten metal. Therefore, the average pore diameter (= r) is preferably 10 nm or more. The average pore diameter is more preferably 20 nm or more, still more preferably 30 nm or more.
On the other hand, if the average pore diameter becomes excessively large, it becomes difficult to cause a capillary phenomenon on the surface of the evaporator. In order to increase the crawling height h, the average pore diameter is preferably 200 μm or less. The average pore diameter is more preferably 100 μm or less, still more preferably 50 μm or less.
The "average pore diameter" refers to the median diameter measured by the mercury intrusion method.

[C. Contact angle]
From equation (1), it can be seen that the contact angle θ must be 0 ° or more and less than 90 ° in order to cause the capillary phenomenon.

[13.4. Evaporator's deemed surface area]
By optimizing the material and surface condition of the evaporator described above, the entire surface of the evaporator can be wetted with molten metal. Therefore, the larger the deemed surface area of the evaporator than the molten metal area, the higher the supply rate of the metal vapor can be.
Here, the "deemed surface area" means the surface area (excluding the area of the bottom surface) of the evaporator calculated assuming that the evaporator has no pores.
The "molten metal area" refers to the area of the molten metal surface when only the molten metal is placed in the crucible.
In order to obtain a high supply rate, the deemed surface area of the evaporator is preferably at least twice the area of the molten metal in the crucible. The deemed surface area is more preferably 3 times or more, still more preferably 5 times or more the molten metal area.

When the evaporator is floating on the surface of the molten metal, the increase in the molten metal area caused by the surface of the evaporator getting wet with the molten metal is kept substantially constant regardless of the remaining amount of the molten metal in the crucible.
On the other hand, when the vicinity of the bottom surface of the evaporator is in a state of being submerged in the molten metal, strictly speaking, the increment of the molten metal area changes depending on the remaining amount of the molten metal in the crucible. However, by optimizing the cross-sectional shape of the evaporator, it is possible to minimize the fluctuation of the increment of the molten metal area due to the fluctuation of the remaining amount of the molten metal.

[1.3.5. Evaporator shape]
The shape of the evaporator is not particularly limited, and the optimum shape can be selected so that the target metal vapor supply rate can be obtained.

For example, the evaporator may include a pedestal and a plurality of fins erected radially on the pedestal. The shape of the pedestal, the shape of the fins, the number of fins, and the like are not particularly limited. For example, the pedestal may be in the shape of a disk, or may be in the shape of each plate. Further, each fin may be a rectangular fin (fin A), or may be a fin (fin B) having a shape in which one corner of the rectangle is cut off.
Further, the individual fins may have the same shape or may have different shapes. For example, four fins A and four fins B may be erected radially and alternately on the surface of the pedestal.

FIG. 1 shows a schematic diagram of another structural example of the evaporator.
The evaporator shown in FIG. 1 (a) is simply a cylinder. Even an evaporator composed of such a large mass can increase the supply rate of metal vapor because the deemed surface area increases.
The evaporator shown in FIG. 1B has a structure in which columnar members such as a plurality of elongated cylinders and prisms are arranged. In order to stabilize the columnar member in the crucible, a plurality of columnar members may be fixed to the pedestal.

The evaporator shown in FIG. 1 (c) has a tree-shaped structure, and includes a plurality of disks and a columnar member connecting the central portions of these disks. Even in a tree-type evaporator, if the surface condition of the evaporator is optimized, the molten metal can crawl up from the lower surface to the upper surface of the disk.
The evaporator shown in FIG. 1D has a columnar shape and is provided with a plurality of through holes in the axial direction. By forming the through hole, the deemed surface area of the evaporator can be further increased as compared with FIG. 1 (a).

In addition, the evaporator may be a member processed into a mesh shape or a member in which such members are arranged in a fin type or a tree type.
When such an evaporator is brought into contact with the molten metal, the molten metal crawls up the surface of the evaporator, and eventually the entire surface of the evaporator becomes wet with the molten metal. Therefore, the larger the deemed surface area, the higher the supply rate of the metal vapor. Specifically, the supply amount of metal vapor can be increased to several times to several tens of times as compared with the case without an evaporator.

[1.4. Carrier gas supply unit]
The metal steam generator according to the present embodiment may further include a carrier gas supply unit that supplies carrier gas into the crucible.
Even a device consisting only of a crucible and an evaporator can supply metal vapor through the opening of the crucible. However, there is a limit to the supply rate of metal vapor only by natural convection. In such a case, it is preferable to supply the carrier gas into the crucible and forcibly discharge the metal vapor from the crucible.

The type of carrier gas is not particularly limited, and the optimum gas is selected according to the type of metal vapor. Examples of the carrier gas include argon gas, nitrogen gas, hydrogen gas, helium gas, and Zenon gas.

The method of supplying the carrier gas is not particularly limited.
For example, a nozzle for blowing carrier gas may be provided on the upper part of the crucible. When the carrier gas is blown from above the crucible toward the opening of the crucible, the flow of the carrier gas is reversed in the crucible, and the carrier gas containing metal vapor can be forcibly discharged from the opening of the crucible.
Alternatively, a nozzle for blowing carrier gas may be provided on the side surface of the crucible. When the carrier gas is blown horizontally from the side surface of the crucible, the flow of the carrier gas changes from the horizontal direction to the upward direction in the crucible, and the carrier gas containing metal vapor can be forcibly discharged from the opening of the crucible.

[2. Metal / metal compound manufacturing equipment (1)]
The metal / metal compound manufacturing apparatus according to the first embodiment of the present invention is
The metal steam supply device according to the first embodiment of the present invention and
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
It is provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited on the surface.

[2.1. Metal compounds]
The apparatus according to the present invention can produce not only metals but also single crystals, thin films, nanoparticles and the like of metal compounds. Examples of the metal compound that can be produced include
(1) Ga ₂ O ₃ , ZnO, TiO ₂ , V ₂ O ₃ , MgO, Al ₂ O ₃ , CaO, Cr ₂ O ₃ , Mn ₂ O ₃ , Co ₂ O ₃ , NiO, CuO, Nb ₂ O ₃ , Mo ₂ O ₃ , Ag ₂ O ₃ , In ₂ O ₃ , Pd ₂ O ₃ , Pt ₂ O ₃ , Ta ₂ O ₃ , Ge ₂ O ₃ , Fe ₂ O ₃ , Y ₂ O ₃ , lanthanoid oxide, etc. Metal oxides (including those with different composition ratios),
(2) Metal nitrides such as GaN, InN, AlN, BN, TiN, NbN, TaN, MoN, WN, MgN, Ca ₃ N ₂ , Fe ₁₆ N ₂ , AgN, InGaN, AlGaN, InAlN, InAlGaN, etc.
(3) _{Metal borides such as MgB 2} , LaB ₆ , CaB ₆ , YB ₆ , YbB ₁₂ , ZrB ₁₂ , NaB ₁₅ , Mn ₄ B, V ₃ B, FeB, CrB ₂ (for example, those having different composition ratios). , YB ₂ , YB _25, etc.)),
_{(4) NaC 2, CaC 2} , LaC 2, Li 4 C 3, TiC, Mg 2 C, Al 4 C 3, Be 2 C, NbC, NbC 2, Nb 4 C 3, HfC, TaC, Ta 4 C 3 , Mo ₃ C ₂ , WC, VC, Cr ₂₃ C ₆ , Cr ₃ C, Cr ₇ C ₃ , Cr ₃ C ₂ , MnC ₂ , FeC, ZrC and other metal carbides (including those with different composition ratios),
(5) _{Metal arsenides such as GaAs, Na 3} As, Mg ₃ As ₂ , FeAs ₂ , CoAs ₂ , NiAs, InAs, PtAs ₂ (including those having different composition ratios),
and so on.

[2.2. Metal steam supply device]
The metal vapor supply device is a device for generating metal vapor. Since the details of the metal steam supply device are as described above, the description thereof will be omitted.

[2.3. Reaction gas supply device]
The reaction gas supply device is a device for supplying the reaction gas to the metal vapor supplied from the metal vapor supply device.

[2.3.1. Reaction gas]
In the present invention, the "reaction gas" refers to a gas that produces a metal or a metal compound having a desired property (for example, composition, crystal structure, shape, etc.) from a metal vapor. In the present invention, the "reaction" includes not only a chemical reaction but also a physical reaction such as a phase transformation. That is, for the reaction gas,
(A) An active gas that produces a metal compound by chemically reacting with a metal vapor, and
(B) An inert gas that produces metal nanoparticles by quenching the metal vapor,
Is included.

The optimum type of reaction gas to be used is selected according to the composition of the metal vapor and the desired reaction.
For example, examples of the reaction gas (active gas) for producing metal nitride from metal vapor include ammonia gas and nitrogen gas.
Examples of the reaction gas (active gas) for producing a metal oxide from the metal vapor include oxygen gas, nitric oxide gas, nitrous oxide gas, ozone gas, and carbon dioxide.
Examples of the reaction gas (active gas) for producing metal carbide from metal vapor include methane gas.
Examples of the reaction gas (active gas) for producing a metal boride from the metal vapor include borazine, diboran gas, and ammonia borane gas.
Examples of the reaction gas (active gas) for producing metal arsenide from metal vapor include arsine and the like.
Examples of the reaction gas (inert gas) for generating metal nanoparticles from metal vapor include argon gas, nitrogen gas, helium gas, and Zenon gas.

[2.3.3. Reaction gas supply method]
The method for supplying the reaction gas is not particularly limited, and the optimum method is selected so that the target metal or metal compound can be efficiently obtained.
As a method of supplying the reaction gas, for example, there are the following methods.
(1) A method in which a nozzle is provided on the outside of the crucible, a reaction gas is blown onto the metal vapor emitted from the opening of the crucible, and the metal vapor and the reaction gas are mixed.
(2) A method in which a reaction gas is poured into a crucible together with a carrier gas, and the metal vapor and the reaction gas are mixed.
(3) A method in which a reaction gas is sprayed onto the metal vapor released from the crucible portion by using a nozzle or the like on the susceptor portion and mixed.

[2.4. Suceptor section]
The susceptor portion is for holding a substrate on which the metal or a compound thereof is deposited. Further, the susceptor portion is also for holding the substrate at a predetermined temperature.
When the metal vapor supplied from the metal steam supply device and the reaction gas supplied from the reaction gas supply device are mixed and the substrate heated to an appropriate temperature is exposed to the mixed gas, single crystals grow on the surface of the substrate and become single crystals. Alternatively, thin films and nanoparticles are deposited on the surface of the substrate.
The structure, installation position, etc. of the susceptor portion are selected so that the substrate can be reliably held, the substrate can be maintained at a predetermined temperature, and the target metal or metal compound can be efficiently obtained. Is preferable.

The optimum material for the substrate is selected so that the target substance can be obtained efficiently. Examples of the material of the substrate include the following.
(1) A single crystal substrate (seed crystal) having the same composition as the target substance.
(2) A single crystal substrate (seed crystal) made of a material having a composition different from that of the target substance but having lattice consistency.
(3) A single crystal substrate or a polycrystalline substrate made of a material having poor wettability with respect to a target substance.
(4) A substrate that is not lattice-consistent with the target substance but has no unbonded hands on the substrate surface. For example, a substrate such as graphene, HOPG, BN.

[3. Method for producing metal nitride single crystal (1)]
In the method for producing a metal nitride single crystal according to the first embodiment of the present invention, a metal vapor is produced in the coexistence of a nitride gas by using the metal / metal compound production apparatus according to the first embodiment of the present invention. It is characterized in that it is generated and a metal nitride single crystal is grown on the substrate. Examples of the nitriding gas include ammonia gas and nitrogen gas.
When a substrate (seed crystal) is held in the susceptor portion, metal vapor is generated using a metal steam supply device, and nitride gas is supplied using a reaction gas supply device, a metal nitride single crystal grows on the substrate surface. To do. Since the metal steam supply device according to the present invention supplies a large amount of metal steam, if the shape and microstructure of the evaporator are optimized, the growth rate of the metal nitride is about 3 to 5 times or more as compared with the conventional method. Become.

By generating one kind of metal vapor from the metal vapor supply device, a single-phase metal nitride single crystal can be produced. On the other hand, when two or more crucibles are installed in the metal steam supply device and two or more kinds of metal steam are generated at the same time, a single crystal composed of a single-phase metal nitride containing two or more kinds of metal elements, or 2 It is possible to produce a single crystal composed of a mixed crystal of metal nitrides of more than one species.
For example, when the metal vapor contains any one or more elements selected from the group consisting of Ga, In, and Al, the metal / metal compound manufacturing apparatus according to the present invention is used to produce GaN, InN, AlN, InGaN, and the like. A single crystal made of AlGaN, InAlN, or InAlGaN can be produced.

[4. Nanoparticle manufacturing method (1)]
The method for producing nanoparticles according to the first embodiment of the present invention is the method for producing nanoparticles according to the first embodiment of the present invention, using the metal / metal compound production apparatus according to the first embodiment of the present invention, in the presence of an active gas or an inert gas. It is characterized in that steam is generated to precipitate metal nanoparticles or metal compound nanoparticles on the substrate.
When a substrate made of a material having poor wettability with respect to a target substance is held in the susceptor portion, metal vapor is generated using a metal steam supply device, and an active gas is supplied using a reaction gas supply device. , Metal compound nanoparticles are deposited on the surface of the substrate.
On the other hand, when the inert gas is supplied using the reaction gas supply device, metal nanoparticles are deposited on the surface of the substrate.

[5. Metal steam supply device (2)]
The metal steam supply device according to the second embodiment of the present invention has the following configuration.
(1) The metal steam supply device is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
(2) The evaporator is
Relative density is 40% or more and 99% or less,
The average pore diameter is 10 nm or more and 200 μm or less, and
It is made of a material having a contact angle of the molten metal of less than 90 °.
(3) The material of the evaporator is made of TaC.
The molten metal is
(A) In and / or Al, or
(B) Ga and In and / or Al
Consists of.

In this embodiment, the material of the evaporator is TaC. Further, the molten metal contains at least In and / or Al. In addition to these, the molten metal may further contain Ga. This point is different from the first embodiment. The other points regarding the metal steam supply device are the same as those in the first embodiment, and thus the description thereof will be omitted.

[6. Metal / metal compound manufacturing equipment (2)]
The metal / metal compound manufacturing apparatus according to the second embodiment of the present invention is
The metal steam supply device according to the second embodiment of the present invention and
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
It is provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited on the surface.

In this embodiment, the material of the evaporator is TaC. Further, the molten metal contains at least In and / or Al. In addition to these, the molten metal may further contain Ga. Examples of the metal nitride produced by using the metal / metal compound production apparatus according to the present embodiment include InN, AlN, InGaN, AlGaN, InAlN, and InAlGaN. This point is different from the first embodiment. The other points regarding the metal / metal compound manufacturing apparatus are the same as those in the first embodiment, and thus the description thereof will be omitted.

[7. Nanoparticle manufacturing method (2)]
The method for producing nanoparticles according to the second embodiment of the present invention uses the metal / metal compound production apparatus according to the second embodiment of the present invention to produce the metal in the presence of an active gas or an inert gas. It is characterized in that steam is generated to precipitate metal nanoparticles or metal compound nanoparticles on the substrate.

In this embodiment, the material of the evaporator is TaC. Further, the molten metal contains at least In and / or Al. In addition to these, the molten metal may further contain Ga. This point is different from the first embodiment. Other points regarding the method for producing nanoparticles are the same as those in the first embodiment, and thus the description thereof will be omitted.

[8. Action]
When a part of the evaporator is brought into contact with the molten metal held in the rutsubo, the molten metal crawls up the surface of the evaporator toward the tip of the evaporator due to capillarity, and at least a part of the surface of the evaporator gets wet with the molten metal. Further, by optimizing the material, shape and microstructure of the evaporator, the creeping height of the molten metal becomes high, and the entire surface of the evaporator can be wetted with the molten metal. As a result, the total area of the liquid surface of the molten metal increases by the amount corresponding to the deemed surface area of the evaporator, and the supply rate of the metal vapor increases. By optimizing the microstructure of the evaporator, the supply amount of the metal source can be increased from several times to several tens of times that of the conventional method.

Further, since the capillary phenomenon is used in the present invention, even if the molten metal on the surface of the evaporator evaporates, the molten metal continues to be supplied to the surface of the evaporator while the molten metal remains in the crucible. Therefore, the surface of the evaporator is always wet with the molten metal, and the supply amount of the metal vapor can be kept substantially constant. When such a metal steam supply device is applied to the growth of, for example, a GaN single crystal, the growth rate of the GaN single crystal can be improved about 3 to 5 times or more as compared with the conventional method.

Such a high growth rate is realized by the molten metal crawling up on the surface of the evaporator. Such a crawling phenomenon is caused by a capillary phenomenon, and the crawling height h is expressed by the above-mentioned equation (1). From equation (1), it can be seen that the capillary phenomenon depends on the contact angle θ, the surface tension γ _{L of the} molten metal, the inner diameter r of the capillary, and the density ρ of the molten metal.
Of these, the surface tension γ _L and the density ρ are determined by the type of molten metal. On the other hand, the contact angle θ is determined by the surface tension and interfacial tension between the molten metal and the evaporator, and the inner diameter r of the capillary tube is determined by the pore structure on the surface and inside of the evaporator. Therefore, if these are optimized, a crawl height h sufficient to wet the entire surface of the evaporator can be obtained.

Non-Patent Document 1 discloses a method of covering the surface of ceramic beads with liquid Ga. However, in the method described in the same document, the amount of liquid Ga on the surface of the ceramic beads decreases as the vaporization progresses, and the liquid Ga is not replenished on the surface of the ceramic beads. Therefore, in the method described in the same document, the supply amount of the metal vapor temporarily increases, but the high supply rate cannot be maintained for a long time.
On the other hand, according to the apparatus according to the present invention, not only the supply amount of metal vapor can be increased, but also a high supply rate can be maintained for a long period of time.

When metal vapor is generated using an evaporator, the partial pressure of the metal vapor in the carrier gas can be increased to near the saturated vapor pressure. Therefore, when a gas containing metal vapor is reacted with an active gas such as oxygen or ammonia, metal oxides, metal nitrides, metal borides, metal carbides, metal arsenides, metal sulfides, etc. are produced. Can be done. At this time, if a substrate made of a product material and a material having poor wettability (for example, a sapphire substrate, a SiC substrate, etc.) is used, nanoparticles made of these substances are precipitated on the surface of the substrate.

On the other hand, when an inert gas such as nitrogen or argon is used instead of the active gas to rapidly cool or pressurize the metal vapor, nuclei are generated in the gas near the saturated vapor pressure of the metal vapor, and the metal nanoparticles Can be easily produced. The diameter 2r of the nanoparticles roughly follows ^{the critical nuclear radius r * of Eq. (2) below.} Therefore, the nanoparticle diameter can be controlled by adjusting the degree of supersaturation according to the cooling temperature, the pressurizing pressure, or the like.
2r ^* = 4σv _l / Δμ ・ ・ ・ (2)
However, σ: surface energy of molten metal, v _l : volume of molten metal liquid atom (molecule),
Δμ: degree of supersaturation.

(Example 1: Relative density dependence of crawling height and average pore size dependence)
[1. Test method]
A rod (5 mm square x 200 mm in length) simulating an evaporator was erected in a crucible containing molten Ga, and the crawling height of Ga was measured. The molten metal temperature was 1150 ° C. As the bar, WC having a relative density of 95% and an average pore diameter of 14.5 μm was used.

[2. result]
[2.1. Relative density dependence]
FIG. 2 shows the relative density dependence of the climbing height when the evaporator is WC and the molten metal is Ga. In addition, FIG. 2 also shows a theoretical curve (solid line) of relative density dependence. For the relationship between the relative density and the climbing height, the above-mentioned equation (1) was used. From FIG. 2, the following can be seen.
(1) The larger the relative density, the larger the climbing height.
(2) In order to make the crawling height 1 cm or more, it is necessary to make the relative density 40% or more.
(3) If the relative density is too high, the pores that cause the capillary phenomenon disappear, so that crawling does not occur. The appropriate relative density is in the region of 40% or more and 99% or less.

[2.2. Average pore size dependence]
FIG. 3 shows the average pore size dependence of the crawling height when the evaporator is WC and the molten metal is Ga. In addition, FIG. 3 also shows a theoretical curve (solid line) depending on the average pore size. From FIG. 4, the following can be seen.
(1) The larger the average pore diameter, the smaller the crawling height.
(2) In order to make the standardized climbing height 1 or more, it is necessary to make the average pore diameter 200 μm or less. In order to cause the capillary phenomenon, the continuum approximation of the liquid metal needs to be established, and for that purpose, the average pore diameter needs to be 10 nm or more.

(Example 2: Preparation of GaN single crystal)
[1. Test method]
A GaN single crystal was grown on the substrate using the apparatus according to the present invention. A sapphire substrate having good lattice consistency with GaN was used as the substrate. The sapphire substrate was previously carros-cleaned to remove impurities. As the evaporator, WC evaporators having different area ratios (= deemed surface area / molten metal area) were used.

An evaporator was placed in the crucible, and a predetermined amount of metal Ga was placed therein. The sapphire substrate was fixed to the susceptor pedestal, and the temperature inside the apparatus was raised to about 1100 ° C. The temperature of the crucible was 1150 ° C., and the pressure inside the device was 1 to 100 kPa. Nitrogen was used as the carrier gas of Ga steam, and the nitrogen flow rate was 1 to 20 slm. A mixed gas of ammonia and hydrogen was used as the reaction gas. The ammonia flow rate was 1 to 20 slm, and the hydrogen flow rate was 0 to 20 slm.

[2. result]
Using the apparatus according to the present invention, a GaN single crystal could be grown on a sapphire substrate. FIG. 4 shows the relationship between the area ratio (= deemed surface area / molten metal area) of the WC evaporator and the growth rate of GaN. Note that FIG. 4 shows the results under the conditions of a carrier gas flow rate of 2 slm and an apparatus internal pressure of 1.3 kPa. The average growth rate of the HVPE method, which is most used for manufacturing GaN substrates, is 100 μm / h (Reference 3).
[Reference 3] K. Fujito et al., Journal of Crystal Growth, 311, 3011-3014, 2009

From FIG. 4, the following can be seen.
(1) When the area ratio is 2 or more, the growth rate becomes equal to or higher than that of the HVPE method.
(2) When the area ratio is 3 or more, the growth rate becomes about 200 μm / h or more.
(3) When the area ratio is 4 or more, the growth rate becomes about 300 μm / h or more.
(4) When the area ratio is 5 or more, the growth rate becomes about 400 μm / h or more.
(5) When the area ratio is 6 or more, the growth rate becomes about 500 μm / h or more.
(6) When the area ratio is 7 or more, the growth rate becomes about 600 μm / h or more, and when the area ratio is optimized, the growth rate exceeds 700 μm / h.

(Examples 3 to 4, Comparative Example 1: Evaporator material dependence of crawling height)
[1. Test method]
As described above, as the evaporator material, metal oxides, oxides, borides, nitrides, carbon-based materials, etc. are listed as candidates because of their characteristics such as high melting point and low reactivity with metal materials. Be done. In fact, Patent Document 2 reports TaC. With respect to crawling, crawling of molten metal occurs when the following equation (3) holds for surface tension (see Table 1) (see References 4 and 5).
σ _metal <σ _evaporator ... (3)
However,
σ _metal : Surface tension of molten metal,
σ _evaporator : Surface tension of the evaporator material.
[Reference 4] GVSamsonov and IMVinitskii, Handbook of refractory compounds, (IFI PLENUM 1980)
[Reference 5] L. Vitos et al., Surface Science 411 186-202 (1998)

However, few data have been reported on the contact angles of various materials, the surface tension of molten metals and evaporator materials, and the interfacial tension between both materials. Furthermore, since the reliability of these physical property values at the operating temperature of the evaporator (around 1000 ° C.) is poor, it was unclear which material is most suitable as the evaporator.
Therefore, from among the candidate materials for the evaporator,
(A) TiC, VC, ZrC , NbC, Mo 2 C, WC, HfC, TiN, TaN, ZrN, and, HfN (Example 3),
(B) TaC (Example 4), and
(C) Cr ₃ C ₂ , VN, Al ₂ O ₃ , BN, C, and SiC (Comparative Example 1)
Was selected and the crawling heights of the molten metal were compared.

Specifically, a bar (5 mm square x 200 mm in length) simulating an evaporator was erected in a crucible containing a metal (Ga, In, or Al), and the temperature of the bar was raised to a predetermined temperature. The climbing height of the molten metal was measured. As each bar, a material having a relative density of about 95% and an average pore diameter of 10 to 15 μm was used.

[2. result]
[2.1. Crawling height of molten Ga]
FIG. 5 shows the climbing height of the molten Ga when the temperature of the evaporator material is raised to 1150 ° C. When the temperature of the molten Ga is 1250 ° C., although not shown, TaC crawls equal to or higher than a specific transition metal carbide made of TiC or the like and a specific transition metal nitride made of TiN or the like (Example 3). The rising height was shown. On the other hand, when the temperature of the molten Ga was 1150 ° C., the Ga crawling height of the specific transition metal carbide made of TiC or the like and the specific transition metal nitride made of TiN or the like was higher than that of TaC.
On the other hand, in Cr ₃ C ₂ , VN, and SiC, Ga crawled up, but the crawling height was lower than that of TaC. Furthermore, in BN and C, no climbing of Ga was observed. From FIG. 5, it can be seen that when an evaporator is produced using a specific transition metal carbide or transition metal nitride, Ga vapor can be supplied more efficiently than TaC.

[2.2. Crawling height of molten In]
FIG. 6 shows the climbing height of the molten In when the temperature of the evaporator material is raised to 800 ° C. When the temperature of the In molten metal was 800 ° C., high creep was observed in the transition metal carbides and transition metal nitrides other than _{Cr 3} C _{2 and VN.} Since the temperature is 800 ° C., a simple comparison cannot be made, but the one showing a higher climb than TaC was different from the case of molten Ga. These results, in the molten In, creeping up height 1cm above _{TaC, Mo 2 C, VC,} WC, TiN, ZrN, HfN, TaN, TiC, ZrC, NbC, or HfC By using the efficient It was found that the metal In vapor can be supplied.

[2.3. Crawling height of molten Al]
FIG. 7 shows the climbing height of the molten Al when the temperature of the evaporator material is raised to 1200 ° C. 7 that the supply of metal Al _{vapor, TaC, Mo 2 C, VC} , WC, TiN, ZrN, HfN, TaN, TiC, seen ZrC, NbC, or HfC that is suitable.

As described above, it was shown that the creeping height of the molten metal differs depending on the combination of each molten metal and the evaporator material. From these results, an evaporator material suitable for each molten metal, which is difficult to obtain simply from the material data as shown in Table 1, was identified.

(Example 5: AlN bulk crystal growth)
[1. Test method]
AlN bulk crystals were grown on the seed substrate using the apparatus according to the present invention. The seed substrate was previously carros-cleaned to remove impurities. The evaporator was used Mo ₂ C steel evaporator.

An evaporator was placed in the crucible, and a predetermined amount of metal Al was added. The seed substrate was fixed to the susceptor pedestal, and the temperature inside the apparatus was raised to about 2000 ° C. The temperature of the crucible was 2300 ° C., and the pressure inside the device was 1 to 100 kPa. _{N 2} was used as the reaction gas, _{and the N 2} flow rate was 1 to 20 slm.

[2. result]
Using the apparatus according to the present invention, AlN crystals having a thickness of 100 μm or more could be grown on the seed substrate. When the evaporator was used, the growth rate was about 100 μm / h.

(Example 6: InN bulk crystal growth)
[1. Test method]
InN bulk crystals were grown on the seed substrate using the apparatus according to the present invention. The seed substrate was previously carros-cleaned to remove impurities. As the evaporator, a WC evaporator was used.

An evaporator was placed in the crucible, and a predetermined amount of metal In was added. The seed substrate was fixed to the susceptor pedestal, and the temperature inside the apparatus was raised to about 800 ° C. The temperature of the crucible was 800 ° C., and the pressure inside the device was 1 to 100 kPa. Nitrogen was used as the carrier gas of In steam, and the nitrogen flow rate was 1 to 10 slm. Ammonia was used as the reaction gas, and the flow rate of ammonia was 0.5 to 3 slm.

[2. result]
Using the apparatus according to the present invention, InN crystals having a thickness of 10 μm or more could be grown on the seed substrate. When the evaporator was used, the growth rate was about 20 μm / h.

(Example 7: Preparation of gallium oxide nanoparticles)
[1. Test method]
Gallium oxide nanoparticles were prepared using the apparatus according to the present invention. A sapphire substrate having low wettability to gallium oxide was used as the substrate. The sapphire substrate was previously carros-cleaned to remove impurities. As the evaporator, a WC evaporator was used.

An evaporator was placed in the crucible, and a predetermined amount of metal Ga was placed therein. The sapphire substrate was fixed to the susceptor pedestal, and the temperature of the sapphire portion was raised to 1000 ° C. The temperature of the crucible was 1150 ° C., and the pressure inside the device was 4 kPa. Nitrogen was used as the carrier gas of Ga steam, and the nitrogen flow rate was 0.1 slm. A mixed gas of oxygen and nitrogen was used as the reaction gas. The oxygen flow rate was 1.0 slm, and the nitrogen flow rate was 4.0 slm.

[2. result]
With the apparatus according to the present invention, gallium oxide nanoparticles having a size of about 100 nm were obtained. It is considered that this is because the carrier gas containing Ga vapor reacts with the oxygen gas at the crucible outlet and is rapidly cooled, so that nuclei are generated in the gas and nanoparticles are formed on the substrate. Be done.
In this embodiment, particles having a relatively large size of about 100 nm were formed, but nanoparticles of an arbitrary size can be formed by controlling the quenching temperature and pressurizing conditions at the crucible outlet. it can.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention.

The metal / metal compound production apparatus according to the present invention can be used for producing a single crystal, a thin film, or nanoparticles composed of various metals or metal compounds.

Claims (17)

A metal steam supply device having the following configurations.
(1) The metal steam supply device is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
(2) The evaporator is
Relative density is 40% or more and 99% or less,
The average pore diameter is 10 nm or more and 200 μm or less, and
It is made of a material having a contact angle of the molten metal of less than 90 °.
(3) the material of the evaporator, TiC, VC, ZrC, NbC , Mo 2 C, WC, HfC, TiN, TaN, ZrN, or made of HfN. The metal steam supply device according to claim 1, wherein the molten metal contains any one or more elements selected from the group consisting of Ga, In, and Al. The metal steam supply device according to claim 1 or 2, wherein the deemed surface area of the evaporator is at least twice the area of the molten metal in the crucible. The evaporator is
With the pedestal
The metal steam supply device according to any one of claims 1 to 3, further comprising a plurality of fins erected radially on the pedestal. The metal steam generator according to any one of claims 1 to 4, further comprising a carrier gas supply unit that supplies carrier gas into the crucible. The metal steam supply device according to any one of claims 1 to 5.
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
A metal / metal compound manufacturing apparatus provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited on the surface. A method for producing a metal nitride single crystal, wherein the metal vapor is generated in the coexistence of a nitride gas to grow the metal nitride single crystal on the substrate by using the metal / metal compound production apparatus according to claim 6. The metal vapor contains any one or more elements selected from the group consisting of Ga, In, and Al.
The method for producing a metal nitride single crystal according to claim 7, wherein the metal nitride is composed of GaN, InN, AlN, InGaN, AlGaN, InAlN, or InAlGaN. Using the metal / metal compound manufacturing apparatus according to claim 6, the nanoparticles that generate the metal vapor in the presence of an inert gas or an active gas and precipitate the metal nanoparticles or the metal compound nanoparticles on the substrate. Production method. A metal steam supply device having the following configurations.
(1) The metal steam supply device is
A crucible for holding molten metal,
Equipped with an evaporator to promote the generation of metal vapor,
The evaporator is installed in the crucible so that a part of the evaporator can come into contact with the molten metal.
(2) The evaporator is
Relative density is 40% or more and 99% or less,
The average pore diameter is 10 nm or more and 200 μm or less, and
It is made of a material having a contact angle of the molten metal of less than 90 °.
(3) The material of the evaporator is made of TaC.
The molten metal is
(A) In and / or Al, or
(B) Ga and In and / or Al
Consists of. The metal steam supply device according to claim 10, wherein the deemed surface area of the evaporator is at least twice the area of the molten metal in the crucible. The evaporator is
With the pedestal
The metal steam supply device according to claim 10 or 11, further comprising a plurality of fins erected radially on the pedestal. The metal steam generator according to any one of claims 10 to 12, further comprising a carrier gas supply unit for supplying carrier gas into the crucible. The metal steam supply device according to any one of claims 10 to 13.
A reaction gas supply device for supplying a reaction gas to the metal vapor supplied from the metal vapor supply device, and
A metal / metal compound manufacturing apparatus provided with a susceptor portion for holding a substrate on which the metal or a compound thereof is deposited on the surface. A method for producing a metal nitride single crystal, wherein the metal vapor is generated in the coexistence of a nitride gas to grow the metal nitride single crystal on the substrate by using the metal / metal compound production apparatus according to claim 14. The metal steam
(A) In and / or Al, or
(B) Ga and In and / or Al
Including
The method for producing a metal nitride single crystal according to claim 15, wherein the metal nitride is composed of InN, AlN, InGaN, AlGaN, InAlN, or InAlGaN. A metal / metal compound manufacturing apparatus according to claim 14, wherein the metal vapor is generated in the coexistence of an inert gas or an active gas, and the metal nanoparticles or the metal compound nanoparticles are precipitated on the substrate. Production method.

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