JP2010083683A - Production method of single crystal body and production apparatus for single crystal body - Google Patents

Abstract

Kind Code: A1 A single crystal production method capable of continuously growing a high-quality single crystal with few dislocations and impurities without easily cracking even when the single crystal grows and becomes thick. provide.
A seed substrate 3a is disposed in a reaction heating chamber 2a, a corrosive gas is introduced into the reaction heating chamber 2a as source gases 5a and 5b, and a region including the seed substrate 3a is heated to thereby form a seed substrate. A method for producing a single crystal by vapor-depositing a single crystal 3b on 3a, and in the reaction heating chamber 2a, heat-reflecting metal plates 8a and 8b subjected to corrosion resistance treatment are provided with reflective surfaces, It arrange | positions toward the area | region containing the seed substrate 3a.
[Selection] Figure 1

Description

  The present invention manufactures a single crystal suitable for growing a group III nitride single crystal (group III nitride single crystal) such as GaN, AlN, AlGaN or the like on a surface of a substrate by a vapor phase growth method. The present invention relates to a method and an apparatus for producing a single crystal.

  Nitride objects such as GaN and AlGaN are used in electronic elements such as light emitting elements such as light emitting diodes (LEDs) and semiconductor lasers (LDs), power devices such as transistors and power FETs (Field Effect Transistors). , Expansion of use is expected.

However, Group 3 nitride single crystals such as GaN and AlGaN have a high melting point and a high equilibrium vapor pressure of N (nitrogen), which makes it difficult to produce bulk single crystals from the liquid phase. is there. Therefore, a thin film made of a group III nitride object is vapor-phase grown on a heterogeneous substrate (a substrate made of a material different from the growing nitride object) such as sapphire (Al ₂ O ₃ ), silicon carbide (SiC), and the like Thin films have been used for various devices.

Furthermore, in recent years, a self-standing GaN single crystal substrate has been put into practical use by a vapor phase growth method such as a hydride vapor phase growth method (HVPE method; Hydride Vapor Phase Epitaxy method) (see, for example, Patent Document 1). Research is also being conducted on a method for producing an AlN single crystal by the HVPE method (for example, see Patent Document 2).
Japanese Patent Laid-Open No. 2000-12900 JP 2006-16294 A

  Conventionally, a substrate made of a group III nitride single crystal produced by the HVPE method is grown on a thick film using a sapphire or GaAs substrate as a seed substrate, and then the seed substrate is peeled off to remove a group III nitride single crystal. I have a substrate. However, a dissimilar substrate such as sapphire has a large difference in lattice constant and thermal expansion from the growth of a group III nitride single crystal such as GaN or AlGaN to be grown. For example, the lattice mismatch between sapphire and GaN is 13.7%, and the thermal expansion difference is 50%. Therefore, when GaN is grown epitaxially on sapphire, there are problems that many dislocations are likely to occur and cracking easily occurs.

  Since LEDs require higher brightness and electronic devices require higher power, it is necessary to obtain a substrate with reduced dislocations. Furthermore, in order to use these light-emitting elements and electronic elements for general purposes, it is indispensable to reduce the cost of the substrate, and it is necessary to prevent cracking from the viewpoint of improving the yield. However, the upper limit of the thickness of the thick film growth is about several millimeters. If the thickness is larger than that, the substrate is liable to crack or the quality of the film itself is deteriorated, which hinders the cost reduction of the substrate. Further, currently, there is a demand for a substrate having a large diameter (2 inches or more), but as the diameter is increased, the warpage of the substrate becomes remarkable, and the problem of generation of cracks due to the warpage has also arisen.

  The present invention has been completed in view of the above-described conventional problems, and an object of the present invention is to provide a method and an apparatus for manufacturing a single crystal that solves these problems.

  In the method for producing a single crystal according to the present invention, a seed substrate is disposed in a reaction heating chamber, a corrosive gas is introduced into the reaction heating chamber as a source gas, and a region including the seed substrate is heated, thereby the seed substrate. A method for producing a single crystal by vapor-phase-growing a single crystal on the reaction heating chamber, wherein a heat-reflecting metal plate subjected to corrosion resistance treatment is disposed with the reflecting surface facing the region. ing.

  The apparatus for producing a single crystal of the present invention includes a reaction heating chamber, a source gas supply pipe provided to introduce a corrosive gas as a source gas into the reaction heating chamber, and a reaction heating chamber. A susceptor for disposing a seed substrate, a heater for heating a region including the seed substrate, and a heat-reflecting metal plate disposed in the reaction heating chamber and subjected to a corrosion resistance treatment. Includes a metal plate for heat reflection disposed toward the region.

In the method for producing a single crystal according to the present invention, a seed substrate is disposed in a reaction heating chamber, a corrosive gas is introduced into the reaction heating chamber as a source gas, and a region including the seed substrate is heated, thereby the seed substrate. A method for producing a single crystal by vapor-phase-growing a single crystal on the reaction heating chamber, wherein a heat-reflecting metal plate subjected to corrosion resistance treatment is disposed with the reflecting surface facing the region. ing.
Due to the action of the heat reflecting metal plate, the temperature of the single crystal is kept uniform during growth or in the cooling process for extraction. In addition, since this heat-reflective metal plate is subjected to corrosion resistance treatment, the metal used will corrode, causing fluctuations in the temperature state of the single crystal and being incorporated as impurities in the crystal. Can be suppressed. Because of the effects as described above, even if the crystal grows and thickens, it is difficult to break, prevents contamination, and stably grows a single crystal in a high quality state. it can.

  The reason why the manufacturing method of the present invention has the above-described effects is presumed as follows.

  First, when a bulk single crystal is vapor-grown by the HPVE method or the like, the concentration of chemical species supplied from the vapor phase is extremely higher than that in the case of conventional thin film formation. These high-concentration chemical species are continuously supplied to the growth surface on the substrate, where they move (migrate) at high speed to form a single crystal. This is made possible by a sufficient temperature at the growth surface.

  Since the temperature (heat) required for such high-speed growth is mainly supplied via a substrate from a susceptor or the like holding the substrate, the seed substrate attached to the susceptor in the conventional open type reaction heating chamber A temperature difference is generated in the plane of the film and in the thickness direction of the grown crystal, and stress due to compositional variation and thermal expansion difference is generated due to the temperature difference. For this reason, it is considered that the problem of deterioration of the substrate, warpage and cracking has conventionally occurred.

  As described above, when high-speed growth of a single crystal is performed in a gas phase, it is extremely important to soak the region where the seed substrate is placed. Thus, the present invention has been devised. That is, in the present invention, by providing the heat reflecting metal plate with the reflecting surface facing the region of the seed substrate, the region where the single crystal is grown on the seed substrate in the reaction heating chamber can be kept soaked. As a result, even a large-diameter seed substrate having a diameter of 2 inches or more is considered to be capable of growing in a state in which a warp is reduced and it is difficult to break and a high quality state is maintained.

  In order to secure a soaking area, even if a metal plate is simply provided, corrosion is caused by ammonia or hydrogen chloride gas used as a raw material gas, and the reflection state of the surface fluctuates. Fluctuations occur and stable results cannot be obtained. In addition, corroded metal atoms may diffuse into the gas phase and be taken into the crystal. On the other hand, in the metal plate for heat reflection according to the present invention, since the surface is subjected to the corrosion resistance treatment, stable and satisfactory results can be obtained.

  According to the above-described method and apparatus for producing a single crystal of the present invention, a high-quality single crystal substrate with few cracks and crystal defects can be obtained. Therefore, the group III nitride single crystal substrate manufactured using the method for manufacturing a single crystal of the present invention includes a light emitting element such as a light emitting diode (LED) and a semiconductor laser (LD), a transistor, and a power FET (Field Effect Transistor). It is suitably used for electronic elements such as power devices.

  Hereinafter, an exemplary embodiment of the method for producing a single crystal of the present invention will be described. In addition, the figure used for the following description is only an example of embodiment of this invention, and is not limited to this. In addition, the size of each member shown in the drawing may be intentionally changed for the purpose of explanation, and is different from the actual ratio.

  FIG. 1 is a schematic cross-sectional view showing an example of a vapor phase growth apparatus which is a single crystal production apparatus of the present invention. FIG. 2 is a schematic view showing an example of a heat reflecting metal plate according to the present invention in the vapor phase growth apparatus S shown in FIG. In FIG. 1, S is a vapor phase growth apparatus, 1 is a holding body (susceptor), 2 is a quartz tube, 2a is a reaction heating chamber, 3a is a seed crystal substrate (seed substrate) for growth, and 3b is a grown single crystal. 4, 4a and 4b are heaters, 5 is a source gas introduction pipe (5a and 5b are source gases), 6 is a counterflow gas flow, 7 is a gallium container, and 8 is a reflector (metal plate for heat reflection). In the vapor phase growth apparatus S shown in FIG. 1, the region sandwiched between the side on which the seed substrate on the holding body 1 is disposed and the source gas injection port in the quartz tube 2 is a reaction heating chamber. It corresponds to 2a.

  Hereinafter, a method for carrying out the method for producing a single crystal of the present invention using the vapor phase growth apparatus S will be specifically described.

(1) The reflecting plate 8 is made of molybdenum having a thickness of 0.5 mm, and after the surface of the reflecting surface is polished, SiO ₂ is coated with a thickness of about 5 μm by sputtering as a corrosion-resistant treatment. . Further, in the present embodiment, as shown in FIG. 2, the reflectors 8a and 8b are respectively supported by heat-resistant metal rods 8c from the upper and lower flanges of the vapor phase growth apparatus. The figure shows an example in which six reflectors 8 are arranged at intervals of 10 mm. Since the reflecting surface of the reflecting plate 8 is arranged toward the heating region (the region on the side where the seed substrate of the holder 1 is disposed) in the reaction heating chamber 2a, the heating region can be soaked. it can.

  As a material constituting the reflecting plate 8, it is desirable to use a metal having heat resistance, and it is desirable to use any one of molybdenum, silver, platinum, and iridium. Among them, it is preferable to use molybdenum that is low in cost and excellent in mechanical strength.

Moreover, the thickness of the reflecting plate 8 can be selected from the range of about 0.1 mm to 1 mm, for example. It is desirable that the surface of the reflecting surface is polished to such an extent that it is glossy. This is because the effect of reflecting and confining heat is high. In addition, as the anti-corrosion treatment, it is desirable to provide a coating film of any one of SiO ₂ , SiC and TaC in a range of 1 μm to 10 μm by sputtering or CVD. If the thickness is within this range, sufficient corrosion resistance can be obtained, and the coating film surface reflects the polished state of the reflecting surface of the reflecting plate 8, and a sufficient heat reflection effect is easily obtained. is there.

  As shown in FIG. 1, it is desirable that the reflector 8 is provided so as to block the cross section of the reaction tube so that the gas flow is not completely blocked. In FIG. 1, the reflecting plate 8a is in a state where the shaft portion of the holding body 1 penetrates the reflecting plate 8a, and the reflecting plate 8b has two source gas introduction pipes 5 penetrating the reflecting plate 8b. It is in a state. By setting it as such a structure, since the route | root which heat | fever goes out from the reaction heating chamber 2a can be block | closed, the effect of the soaking | uniform-heating of a heating region increases.

  In addition, as shown in the figure, the reflector 8 is configured such that a plurality of sheets are spaced one by one and stacked in a direction away from the heating region, preventing heat leakage, This is desirable because the effect of expanding the soaking zone is enhanced. In such a stack structure, as shown in FIG. 2, heat-resistant hollow rod-like spacers 8d and reflectors 8 provided with through holes (not shown) are alternately arranged, and metal rods 8c are formed in the holes. It can be assembled and assembled. In addition, if a screw is cut on the surface of the metal bar 8c, after assembling each member, it can be easily fixed by screwing using fastening members 8e and 8f such as nuts. The number of the reflectors 8 to be stacked may be 2 or more and 10 or less. Further, the interval when the reflecting plates 8a and 8b are arranged in a stack can be adjusted by the length of the spacer 8d, and may be in the range of 1 mm or more and 20 mm or less. In addition, the material which comprises the metal stick | rod 8c, the spacer 8d, and the fastening members 8e and 8f applies to the reflecting plate 8. FIG.

  Next, with the seed substrate 3 a held by the holder 1, the seed substrate 3 a is placed inside the quartz tube 2 of the vapor phase growth apparatus S through the through hole of the reflector 8 a. Although graphite can be used for the support 1, since corrosive ammonia or hydrogen chloride is used as a source gas as will be described later, the surface is coated with one or more selected from the group consisting of SiC, BN and TaC. It is preferable to keep it. Examples of the coating method include a CVD method and a sputtering method. Thereby, the corrosion resistance of the holder 1 is improved. PBN is preferable among BN. PBN is pyrogenic boron nitride (pyrolytic BN (p-BN)).

  Further, it is desirable to provide a mechanism for rotating the seed substrate 3a held around the central axis of the holding body 1 so that the seed substrate 3a rotates during crystal growth. Thereby, the uniformity of the crystal growing on the seed substrate 3a can be improved. In addition, as rotation speed, it is possible to select from the range of about 2 rpm-50 rpm, for example.

  Here, the seed substrate 3a will be described with an example using a group III nitride single crystal. Specifically, a gallium nitride compound semiconductor such as GaN or AlGaN, AlN, or the like can be used. When the group III nitride single crystal is a GaN single crystal, examples of the seed substrate 3a include sapphire, SiC, GaN single crystal, AlN single crystal, or a mixed crystal of GaN single crystal and AlN single crystal. it can. Among them, GaN single crystals, AlN single crystals, or mixed crystals of GaN single crystals and AlN single crystals are preferably used. The thickness of the seed substrate 3a for growth is about 0.3 to 0.6 mm. The diameter of the seed substrate 3a for growth is 20 mm to 60 mm.

  The quartz tube 2 which is the main body of the vapor phase growth apparatus S is made of quartz or the like, and a cylindrical body such as a cylindrical shape or a rectangular tube shape is preferably used. As described above, the region sandwiched between the side on which the seed substrate on the holder 1 is arranged and the source gas injection port in the quartz tube 2 corresponds to the reaction heating chamber 2a according to the present invention.

  (2) Next, the heater 4b on the holding body 1 side is heated to 700 ° C. or higher, the counter flow 6 is introduced together with the source gases 5a and 5b, and the single crystal 3b is grown on the seed substrate 3a.

  As a vapor phase growth method for this purpose, it is preferable to use a hydride vapor phase growth method (HVPE method). Other vapor phase growth methods include metal organic vapor phase growth (MOVPE), sublimation, etc., but the HVPE method is used because of its high growth rate, good quality, and ease of producing nitrided bodies. preferable. Hereinafter, an example using the HVPE method will be described.

  The source gases 5a and 5b use Group V ammonia and Group 3 gallium chloride, and the counterflow 6 uses nitrogen, hydrogen, or a mixed gas thereof. Gallium chloride is produced by filling metal gallium in a quartz gallium container 7 and allowing hydrogen chloride gas to flow at about 800 ° C. for reaction.

  The heaters 4a and 4b are provided around the outer periphery of the quartz tube 2, and, for example, a resistance heating type can be used. The heater 4b on the holder 1 side may heat the holder 1 and the seed substrate 3a by setting the temperature to 500 to 1000 ° C. when forming a low-temperature buffer layer or the like and 1000 to 1300 ° C. when starting single crystal growth. The low-temperature buffer layer is required when a sapphire substrate is used as the growth seed substrate 3a, and is formed at a thickness of 10 to 100 nm. Note that when the low-temperature buffer layer is formed, the gas composition is the same as that for growing the single crystal 3b.

The source gas supplied into the vapor phase growth apparatus S for growing a nitride body is a corrosive gas having corrosivity to metals such as ammonia (NH ₃ ) gas, gallium chloride (GaCl) gas, and hydrogen chloride (HCl) gas. It is. Further, nitrogen (N ₂ ) gas, hydrogen (H ₂ ) gas, silane (SiH ₄ ) gas, or the like may be included.

  When hydrogen chloride gas is used, hydrogen chloride is reacted as gallium metal at a temperature of about 800 ° C. in the gallium container 7 part of the gas supply pipe of the vapor phase growth apparatus S, and supplied as source gas 5b as gallium chloride (GaCl) gas. The For this purpose, the gallium container 7 may be heated by heating the raw material supply side heater 4a to a predetermined temperature. The gallium chloride gas source gas 5b thus generated is supplied with and mixed with ammonia gas from the source gas 5a and supplied to the seed substrate 3a at a predetermined temperature, whereby GaN is formed on the surface of the seed substrate 3a. The single crystal 3b can be grown at high speed. The pressure during the reaction is usually atmospheric pressure (normal pressure) in the HPVE method.

  The flow rate ratio between ammonia gas and hydrogen chloride gas is preferably such that the flow rate of ammonia gas is about 15 to 30 times the flow rate of hydrogen chloride gas. By setting this ratio, the growth rate of the GaN single crystal can be increased, and the growth of columnar crystals that increase dislocations in the GaN single crystal can be suppressed.

  The counter flow 6 makes the source gas laminar so as not to cause turbulent flow, carries reaction products that could not contribute to the growth to the outside of the apparatus, and adheres to the inside of the quartz tube 2. It is a gas flow that is introduced to prevent or prevent. As described above, nitrogen, hydrogen, or a mixed gas thereof can be used, and the flow rate is several times to several tens of times that of the source gases 5a and 5b. Specifically, the flow rate is preferably about 3 to 20 times.

  Conventionally, the crystal growth is performed at a specific temperature of 1000 to 1300 ° C. at the start of the growth, and the crystal growth is performed while maintaining the same temperature, and the reflector 8 is not used. In such a conventional method, there is a tendency that dislocations are generated or cracked according to the growth of the single crystal. On the other hand, in this invention, as mentioned above, the reflecting plate 8 which is the metal plate for heat reflection which performed the corrosion-resistant process was provided. This ensures the temperature inside the reaction tube, especially the in-plane temperature of the seed substrate fixed to the susceptor and the thickness uniformity in the thickness direction of the thickly grown crystal, and prevents high-quality crystal growth with less dislocations and impurities. It becomes possible.

  In order to process the single crystal body 3b of GaN into a substrate shape, a general wafer processing process such as semiconductor silicon can be applied, and generally the following processes may be performed.

  (A) A GaN single crystal grown using a diamond grindstone is ground to a predetermined outer diameter.

  (B) A wire crystal in which a single crystal of GaN is fixed to diamond abrasive grains, or a wire saw that cuts a crystal by a reciprocating motion of a wire while dropping diamond or SiC abrasive grains in a brass wire with a slurry, A wafer having a predetermined thickness (for example, 0.6 mm) is cut out.

  (C) After roughly polishing both surfaces of a single crystal wafer of GaN using diamond abrasive grains or SiC abrasive grains, the surface used in the device process is mirror-polished using colloidal silica, whereby a single crystal of GaN is polished. A wafer substrate is obtained.

  From the above, a nitride substrate made of GaN single crystal suitable for epitaxial growth of a gallium nitride compound semiconductor applied to an optical element and an electronic element can be manufactured.

  Note that the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the scope of the present invention.

For example, a seed substrate 3a made of AlN single crystal is used, aluminum is used instead of gallium, high frequency induction heating coils are used as heaters 4a and 4b, and ammonia (NH ₃ ) gas and hydrogen chloride (HCl) gas are the main components. It is possible to grow an AlN single crystal by supplying the source gas. The same applies to trimethylaluminum, which is an organic metal gas, instead of using metal aluminum instead of hydrogen chloride, which is a raw material gas.

  Moreover, FIG. 1 demonstrated the case where it grew by arrange | positioning so that the growth surface of the single crystal body 3b might become downward with respect to the perpendicular direction with respect to the seed substrate 3a. In this case, it is preferable because dust and the like can be prevented from falling on the growth surface. However, the single crystal body 3b may be arranged so that the growth surface faces upward with respect to the vertical direction or laterally with respect to the vertical direction.

  Furthermore, the vapor phase growth apparatus S is not limited to the shape as shown in FIG. 1, but can be applied to an apparatus for growing a nitride body in the vapor phase, and the source gas is also limited to the materials shown in the embodiments. However, it can be applied to a source gas capable of growing a nitride body.

  Examples of the method for manufacturing a nitride object of the present invention will be described below.

A GaN single crystal was manufactured using the vapor phase growth apparatus S shown in FIG. First, using reflectors 8a and 8b made of molybdenum having a diameter of 90 mm and a thickness of 0.5 mm coated with 5 μm of SiO ₂ , the seed substrate 3a is made of a disk-shaped GaN single crystal having a diameter of 52 mm and a thickness of 0.4 mm Was used. The seed substrate 3a is mounted on a holder 1 made of graphite having a cylindrical shape with an outer diameter of 60 mm and a thickness of 20 mm and coated with 0.2 mm of SiC, which is installed in a quartz tube 2 (an inner diameter of 95 mm) as the vapor phase growth apparatus S. The outer peripheral part was clamped and fixed so that the growth surface faced downward.

  Next, gallium is accommodated in the gallium container 7, the inside of the quartz tube is heated by energizing the resistance heater 4a, and the temperature of gallium is controlled to about 800 ° C. by the heater 4a, while hydrogen chloride gas is supplied at 30 cc / min. The gallium chloride was supplied from 5b as a Group 3 source gas. Almost simultaneously, ammonia gas was supplied in the amount of 750 cc / min as group V source gas 5a. Further, the heater 4b was controlled to 1100 ° C. so that the temperature of the seed substrate 3a was 1000 ° C. Thereby, the growth of the single crystal body 3b of GaN was started while rotating the holder 1 at 20 rpm, and the crystal was grown to a growth thickness of 25 mm.

  After the completion of crystal growth, a single crystal of GaN was taken out from the vapor phase growth apparatus S, and peripheral grinding was performed using a diamond grindstone to an outer diameter of 50.8 mm. Thereafter, a plurality of GaN single crystals obtained by grinding the outer periphery were cut into a thickness of 0.6 mm with a wire saw using a wire having diamond abrasive grains fixed thereon, to obtain a GaN single crystal substrate.

  Next, both sides of the GaN single crystal substrate cut out with a wire saw are roughly polished using diamond abrasive grains, and further, the surface used for crystal growth is mirror-polished by mechanochemical polishing using colloidal silica. A GaN single crystal substrate wafer having a thickness of 50.8 mm and a thickness of 0.4 mm was produced.

When the wafer surface of the GaN single crystal substrate produced as described above was observed with an X-ray topographic image, the average dislocation density was 5 × 10 ⁴ cm ⁻² . Moreover, when the crystal | crystallization was analyzed by SIMS analysis whether the molybdenum used for the reflecting plate 8 mixed in the crystal | crystallization, molybdenum was not detected.

As Comparative Example 1, when a GaN single crystal was produced on a GaN single crystal seed substrate in the same process as in the Example except that the reflector 8 was not used, cracks occurred when the growth thickness was about 5 mm. Happened. Further, when a wafer was produced from the GaN single crystal of this comparative example and the average dislocation density up to 5 mm was measured, it was 2 × 10 ⁵ cm ⁻² , and the effectiveness of the present invention was confirmed in terms of cracks and quality. It was done.

Furthermore, when Comparative Example 2 was the same as Comparative Example 1 except that sapphire was used as a seed substrate, the grown GaN single crystal cracked when the growth thickness exceeded 1 mm. Moreover, the average dislocation density measured by avoiding the cracked portion was about 2 × 10 ⁸ cm ⁻² , and as in Comparative Example 1, the effectiveness of the present invention in terms of generation of cracks and quality was confirmed.

Furthermore, as Comparative Example 3, a GaN single crystal was produced on a GaN single crystal seed substrate in exactly the same process as in the Example except that a molybdenum reflector not coated with SiO ₂ was provided. Did not occur. Moreover, when a wafer was produced from the GaN single crystal of this comparative example and the average dislocation density up to 5 mm was measured, it was 2 × 10 ⁵ cm ⁻² . However, when the molybdenum contamination was analyzed by SIMS, an amount of 3 × 10 ¹⁸ atoms / cc was detected. As described above, the effectiveness of the present invention was confirmed in terms of contamination with impurities.

It is a cross-sectional schematic diagram which shows an example of the vapor phase growth apparatus which is a manufacturing apparatus of the single crystal body of this invention. It is a schematic diagram which shows an example of the metal plate for heat reflection which concerns on this invention in the vapor phase growth apparatus S shown in FIG.

Explanation of symbols

S: Vapor growth apparatus 1: Holding body 2: Quartz tube 2a: Reaction heating chamber 3a: Seed substrate 3b: (Growth) single crystal 4a, 4b: Heater 5: Source gas introduction pipe 5a, 5b: Source gas 6: Gas flow of counter flow 7: Gallium container 8: Reflecting plate (metal plate for heat reflection)
8a, 8b: Reflector 8c: Metal rod 8d: Spacer 8e, 8f: Fastening member

Claims (8)

A seed substrate is disposed in the reaction heating chamber, a corrosive gas is introduced into the reaction heating chamber as a source gas, and a region including the seed substrate is heated to vapor-deposit a single crystal on the seed substrate. A method for producing a crystal,
A method for producing a single crystal, wherein a heat-reflecting metal plate subjected to corrosion resistance treatment is disposed in the reaction heating chamber with a reflecting surface facing the region.   The method for producing a single crystal body according to claim 1, wherein a plurality of the heat reflecting metal plates are stacked at a predetermined interval along a direction away from the region.   The method for producing a single crystal according to claim 1, wherein the heat reflecting metal plate is made of at least one of molybdenum, silver, platinum, and iridium. The corrosive gas contains chloride gas or ammonia gas,
4. The method for producing a single crystal according to claim 1, wherein the corrosion-resistant treatment is to coat any one of SiO ₂ , SiC, and TaC on a surface of the heat reflecting metal plate. 5. .   The method for producing a single crystal according to claim 1, wherein the vapor phase growth method is a hydride vapor phase growth method.   The method for producing a single crystal according to claim 1, wherein the single crystal is composed of a GaN single crystal, an AlN single crystal, or a mixed crystal thereof.   The method for producing a single crystal according to any one of claims 1 to 6, wherein the seed substrate is composed of a GaN single crystal, an AlN single crystal, or a mixed crystal thereof. A reaction heating chamber;
A source gas supply pipe provided to introduce a corrosive gas as a source gas into the reaction heating chamber;
A susceptor disposed in the reaction heating chamber, on which a seed substrate is disposed;
A heater for heating the region including the seed substrate;
A heat-reflective metal plate disposed in the reaction heating chamber and subjected to a corrosion-resistant treatment, the heat-reflective metal plate having a reflective surface disposed toward the region. Manufacturing equipment.