III-nitride semiconductor crystal manufacturing equipment

Abstract

To provide a manufacturing apparatus of group III nitride semiconductor crystal capable of improving the mixability of a group III element-containing gas supplied to a growth area on a substrate and the nitrogen element-containing gas by suppressing precipitation of group III nitride semiconductor crystals on components on a raw material gas introduction path.SOLUTION: The manufacturing apparatus of a group III nitride semiconductor crystal includes: a substrate susceptor for holding a substrate; a raw material nozzle for injecting group III element-containing gas toward the substrate; and a nitrogen source nozzle that injects nitrogen element-containing gas toward the substrate, in which the injection direction intersects with the injection direction of the raw material nozzle in side view, and constitutes a mixing part so that the group III element-containing gas and the nitrogen element-containing gas are mixed around the intersection. The mixing part is placed above the substrate susceptor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a Group III nitride semiconductor crystal manufacturing apparatus, and more particularly to a Group III nitride semiconductor crystal manufacturing apparatus that is a vapor phase growth apparatus that is provided with a nozzle disposed opposite a substrate holding member on which a substrate to be processed is placed within a reactor, and that is provided for supplying gas toward the substrate to be processed. [Background technology]

[0002] Group III nitride semiconductors such as GaN, AlGaN, and InGaN are used in fields such as optical devices such as light-emitting diodes and semiconductor lasers, and heterojunction high-speed electronic devices. One method for producing GaN, a Group III nitride semiconductor, is a practical hydride vapor phase epitaxy (HVPE) method in which a Group III metal element (e.g., Ga metal) is reacted with a chloride gas (e.g., HCl gas) to generate a Group III metal chloride gas (GaCl gas), and GaN is grown from the Group III metal chloride and a nitrogen-containing gas (e.g., NH gas) (see, for example, Patent Document 1).

[0003] However, the HVPE method has the problem that a large amount of NH4Cl (ammonium chloride) is generated as a by-product during crystal growth, clogging the exhaust pipe of the manufacturing equipment and inhibiting crystal growth. To solve this problem, oxygen vapor phase epitaxy (OVPE) has been proposed, in which a group III element metal (e.g., Ga metal) is reacted with an oxidizing agent (e.g., HO gas) to generate a group III element metal oxide gas (Ga2O gas), and GaN is grown from the group III element metal oxide and a nitrogen-containing gas (e.g., NH3 gas) (see, for example, Patent Document 2).

[0004] A feature of the HVPE and OVPE methods is that they can achieve extremely high growth rates of 10 μm / h or more, or even 100 μm / h or more, compared to the typical growth rate of around 1 μm / h in other crystal growth methods such as metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE).For this reason, they are used to manufacture freestanding GaN substrates.

[0005] FIG. 7 is a schematic cross-sectional view showing a typical cross-sectional structure of an OVPE apparatus, which is one of conventional Group III nitride semiconductor crystal manufacturing apparatuses 50. This OVPE apparatus includes a reaction vessel 101 for growing nitride semiconductor crystals. The reaction vessel 101 includes a source vessel 103 installed in a source reaction chamber 102 for generating Group III element gases such as GaO. A metal source 106 containing Ga, In, Al, etc. is contained in the source vessel 103, which is heated by a first heater 104. A reactive gas supply pipe 107 is connected to the source vessel 103, supplying a reactive gas such as HO gas. The reactive gas supplied from the reactive gas supply pipe 107 into the source vessel 103 reacts with the metal source 106 to generate a Group III element-containing gas within the source vessel 103. The generated Group III element-containing gas is introduced into the source vessel 103 through a Group III element-containing gas supply pipe 108 connected to the source vessel 103 and transported to a seed substrate 111 placed on a substrate susceptor 112. The seed substrate 111 is heated by a second heater. A nitrogen-containing gas supply pipe 109 for supplying a nitrogen-containing gas such as NH gas is provided in the reaction vessel 101. The group III element-containing gas and the nitrogen-containing gas transported to the seed substrate 111 react with each other, causing a group III nitride semiconductor crystal to grow on the seed substrate 111.

[0006] As shown in Fig. 7, the group III element-containing gas supply pipe 108 and the nitrogen element-containing gas supply pipe 110 are generally configured perpendicular to the main surface of the seed substrate 111. A drawback of a typical conventional OVPE apparatus is that the group III element-containing gas and the nitrogen element-containing gas are difficult to mix because they are discharged parallel to each other, as shown in Fig. 7. This makes it difficult to control the in-plane uniformity of the film thickness and crystallinity of the group III nitride semiconductor crystal.

[0007] An apparatus configuration for improving the mixability of a group III element-containing gas and a nitrogen element-containing gas is proposed in Patent Document 3. Patent Document 3 describes a structure in which a homogenizing partition such as a mixing chamber or a mixing plate is provided between a gas supply pipe and a substrate in order to uniformly mix the group III element-containing gas and the nitrogen element-containing gas. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 52-23600 [Patent Document 2] WO2015 / 053341 [Patent Document 3] Special Publication 2008-504443 Summary of the Invention [Problem to be solved by the invention]

[0009] The temperature of the metal source 106 in the source vessel 103 of the OVPE apparatus must be maintained at a high temperature of 900°C or higher to react with the group-III metal oxidizing gas and generate a group-III element-containing gas. The growth region on the substrate must also be maintained at a high temperature of approximately 1400°C to increase the driving force of the group-III nitride semiconductor crystal generated from the group-III element-containing gas and the nitrogen-containing gas. Thus, in the OVPE and HVPE methods, the entire reaction region is maintained at a high temperature using a technique called hot wall heating. Therefore, in the configuration described in Patent Document 3, group-III nitride semiconductor crystal precipitates in the mixing chamber or mixing plate. This may result in a decrease in the source components transported to the growth region on the substrate and a slower growth rate. Furthermore, the group-III nitride semiconductor crystal precipitated in the mixing chamber or mixing plate becomes particles and contaminates the group-III nitride semiconductor crystal during growth, causing crystal defects.

[0010] The object of the present invention is to solve the above problems, and to provide a Group III nitride semiconductor crystal manufacturing apparatus that can suppress the precipitation of Group III nitride semiconductor crystal on components along a source gas introduction path, and can improve the mixability of a Group III element-containing gas and a nitrogen element-containing gas that are supplied to a growth region on a substrate. [Means for solving the problem]

[0011] In order to achieve the above object, the Group III nitride semiconductor crystal manufacturing apparatus according to the present invention comprises: a raw material reaction chamber; a raw material reaction section provided in the raw material reaction chamber for generating a group III element-containing gas; a substrate holding member for holding a substrate in the source reaction chamber; a source nozzle that injects the Group III element-containing gas toward the substrate in the source reaction chamber; a nitrogen source nozzle that sprays a nitrogen element-containing gas toward the substrate within the raw material reaction chamber, the spray direction of which intersects with the spray direction of the raw material nozzle before the substrate in a side view from a direction perpendicular to the vertical direction, and forms a mixing section in which the Group III element-containing gas and the nitrogen element-containing gas are mixed around the intersection point; a heating means for heating the raw material reaction chamber, the raw material nozzle, the nitrogen source nozzle, and the substrate holding member within the raw material reaction chamber; a rotation mechanism for rotating the substrate holding member in the source reaction chamber; Equipped with. [Effects of the Invention]

[0012] The Group III nitride semiconductor crystal manufacturing apparatus according to the present invention can suppress the precipitation of Group III nitride semiconductor crystal on components along the source gas introduction path, and improve the mixability of the Group III element-containing gas and the nitrogen element-containing gas supplied to the growth region on the substrate, thereby making it possible to homogenize the gas concentration distribution on the substrate. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view showing an example of the cross-sectional configuration of a Group III nitride semiconductor crystal manufacturing apparatus in accordance with Example 1. FIG. [Figure 2(a)] 2 is a side cross-sectional view showing the cross-sectional structure of the Group III nitride semiconductor crystal manufacturing apparatus of FIG. 1, as viewed from a direction perpendicular to the vertical direction of the source material nozzle and nitrogen source nozzle. FIG. [Figure 2(b)] 2 is a horizontal cross-sectional view of a raw material nozzle and a nitrogen source nozzle viewed from vertically above, using the Group III nitride semiconductor crystal manufacturing apparatus of FIG. 1. FIG. [Figure 3] 1 is a schematic cross-sectional view showing an example of the cross-sectional configuration of a Group III nitride semiconductor crystal manufacturing apparatus according to Comparative Example 1. FIG. [Figure 4] 4 is a diagram showing velocity vector distributions of a group III element-containing gas and a nitrogen element-containing gas in a mixing section according to Example 1. FIG. [Figure 5]10 is a diagram showing velocity vector distributions of a group III element-containing gas and a nitrogen element-containing gas in a mixing section according to Comparative Example 1. FIG. [Figure 6] 10 is a graph showing the relationship between the substrate susceptor rotation speed and the source gas transport efficiency for a group III element-containing gas and a nitrogen element-containing gas according to Examples 1 and 3. [Figure 7] FIG. 1 is a schematic cross-sectional view showing a typical cross-sectional structure of an OVPE apparatus, which is one of conventional Group III nitride semiconductor crystal manufacturing apparatuses. [Figure 8] FIG. 10 is a diagram showing the relationship between the deflection angle of the nitrogen source nozzle and the degree of gas mixing in Example 2. [Figure 9] 1 is Table 1 showing the gas mixing degrees of Comparative Example 1 and Example 1. [Figure 10] 10 is Table 2 showing the transport efficiency of Ga 2 O gas relative to the rotation direction of the substrate susceptor in Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0014] The Group III nitride crystal manufacturing apparatus pertaining to the first aspect comprises a raw material reaction chamber; a raw material reaction section provided in the raw material reaction chamber for generating a group III element-containing gas; a substrate holding member for holding a substrate in the source reaction chamber; a source nozzle that injects the Group III element-containing gas toward the substrate in the source reaction chamber; a nitrogen source nozzle that sprays a nitrogen element-containing gas toward the substrate within the raw material reaction chamber, the spray direction of which intersects with the spray direction of the raw material nozzle before the substrate in a side view from a direction perpendicular to the vertical direction, and forms a mixing section in which the Group III element-containing gas and the nitrogen element-containing gas are mixed around the intersection point; a heating means for heating the raw material reaction chamber, the raw material nozzle, the nitrogen source nozzle, and the substrate holding member within the raw material reaction chamber; a rotation mechanism for rotating the substrate holding member in the source reaction chamber; Equipped with.

[0015] In the manufacturing apparatus for a group-III nitride crystal according to the second aspect, in the above first aspect, the injection port of the raw material nozzle is arranged such that the injection direction is vertically downward, and the injection port of the nitrogen source nozzle may be arranged such that the injection direction is inclined with respect to the vertical direction and deflected with respect to the horizontal direction.

[0016] In the manufacturing apparatus for a group-III nitride crystal according to the third aspect, in the above first or second aspect, the mixing unit may be arranged above the substrate.

[0017] In the manufacturing apparatus for a group-III nitride crystal according to the fourth aspect, in any one of the above first to third aspects, the deflection direction of the nitrogen source nozzle may be in the same direction as the rotation direction of the substrate.

[0018] Hereinafter, a manufacturing apparatus and a manufacturing method for a group-III nitride semiconductor crystal according to an embodiment will be described with reference to the drawings. In the drawings, substantially the same members are denoted by the same reference numerals.

[0019] (Embodiment 1) (Manufacturing Apparatus for Group-III Nitride Semiconductor Crystal) Hereinafter, Embodiment 1 will be described with reference to FIG. 1. FIG. 1 is a schematic cross-sectional view showing an example of a cross-sectional configuration of a manufacturing apparatus for a group-III nitride semiconductor crystal according to Embodiment 1. Note that in FIG. 1, the sizes, ratios, etc. of each component may be different from the actual ones. The Group III nitride crystal manufacturing apparatus according to the first embodiment is a vapor phase growth apparatus that includes a reaction vessel 1 for growing nitride semiconductor crystal, a source vessel 3 for generating a Group III element-containing gas, a source nozzle 8 for spraying the Group III element-containing gas toward seed substrate 11, and a nitrogen source nozzle 10 for spraying a nitrogen element-containing gas toward seed substrate 11. In a side view perpendicular to the vertical direction, the spray direction of nitrogen source nozzle 10 intersects with the spray direction of source nozzle 8 just before seed substrate 11, and a mixing section is formed around the intersection where the Group III element-containing gas and the nitrogen element-containing gas are mixed. Source vessel 3 and source nozzle 8 are connected. The Group III element-containing gas supplied from source nozzle 8 and the nitrogen element-containing gas supplied from nitrogen source nozzle 10 are mixed in the mixing section, and then Group III nitride semiconductor crystal is grown on seed substrate 11, which is placed on substrate susceptor 12, in a growth section above seed substrate 11. The substrate susceptor 12 and a rotary shaft 13 are connected, and the substrate susceptor 12 is rotated by the rotary shaft 13 . Group III nitride semiconductor crystal manufacturing apparatus 20 pertaining to embodiment 1 is able to suppress the precipitation of Group III nitride semiconductor crystal on components along the source gas introduction path, and to improve the mixability of the Group III element-containing gas and nitrogen element-containing gas supplied to growth region 16 on substrate 11. Furthermore, the efficiency of source gas transport to substrate 11 can be increased.

[0020] The components of this Group III nitride semiconductor crystal manufacturing apparatus 20 will be described below.

[0021] <Raw material reaction chamber> A raw material vessel 3 is placed in a raw material reaction chamber 2 equipped with a reactive gas supply pipe 7, and contains a starting Ga source 6, which is a Group III element-containing source. In addition to Ga, the Group III elements used include Al and In, and oxides such as Ga2O3. A first heater 4 is provided on the outer periphery of the raw material reaction chamber 2, and the interior of the raw material reaction chamber 2 is maintained at a desired temperature. To generate a Group III element-containing gas, the temperature is preferably maintained at 900°C or higher and 1300°C or lower. When a reactive gas is supplied to the heated starting Ga source 6, the starting Ga source 6 and the reactive gas react to generate a Group III element-containing gas.

[0022] Methods for generating a Group III element-containing gas include a method for oxidizing the starting Ga source 6 and a method for reducing the starting Ga source 6. As a method for oxidizing the starting Ga source 6, a reaction system using metallic Ga as the starting Ga source 6 and H2O gas as the oxidizing gas will be described. Metallic Ga, which is the starting Ga source 6, is heated, and in this state, H2O gas, an oxidizing gas, is introduced. As shown in the following formula (1), the introduced H2O gas reacts with metallic Ga to generate Ga2O gas, a gas containing a Group III element. 2Ga + H2O → Ga2O + H2(1) Furthermore, an In source or an Al source can be used as a group III element-containing source in addition to the starting Ga source 6. In either case, a group III oxide gas is generated.

[0023] Next, a reaction system using Ga2O3 as the starting Ga source 6 and H2 gas as the reducing gas will be described as a method for reducing the starting Ga source 6. Ga2O3, which is the starting Ga source 6, is heated, and in this state, H2 gas, which is the reducing gas, is introduced. As shown in the following formula (2), the introduced H2 gas reacts with Ga2O3 to generate Ga2O gas, which is a gas containing a Group III element. Ga2O3 + 2H2 → Ga2O + 2H2O (2) As a carrier gas for the oxidizing gas and the reducing gas, an inert gas such as Ar or N2, or H2 gas is used.

[0024] <Material nozzle> The Group III element-containing gas, such as GaO gas, generated in raw material reaction chamber 2 is sprayed vertically downward toward seed substrate 11 from raw material nozzle 8, which is provided downstream of raw material reaction chamber 2. To suppress precipitation of Group III nitride semiconductor crystals into raw material nozzle 8 and nitrogen source nozzle 10, it is preferable that a separate gas outlet be formed on the outer periphery of raw material nozzle 8. The inner diameter of raw material nozzle 8 is not particularly limited, but is preferably in the range of 1 mm to 100 mm, more preferably 20 mm to 60 mm.

[0025] <Nitrogen source nozzle> Nitrogen source nozzle 10 is equipped with a nitrogen-element-containing gas supply pipe 9. Nitrogen-element-containing gas is sprayed from nitrogen source nozzle 10 toward seed substrate 11. In a side view perpendicular to the vertical direction, the spray direction of nitrogen source nozzle 10 intersects with the spray direction of raw material nozzle 8 just before seed substrate 11. A mixing section 14 where the Group III element-containing gas and the nitrogen element-containing gas are mixed is formed around this intersection point 15. Specifically, this mixing section 14 refers to a region extending in the horizontal plane between seed substrate 11 and raw material nozzle 8 / nitrogen source nozzle 10. Examples of nitrogen-containing gases that can be used include NH3 gas, NO gas, NO2 gas, N2H2 gas, and N2H4 gas. The nitrogen-containing gas is sprayed from a nitrogen source nozzle 10 that is inclined relative to the vertical direction in a side view as shown in FIG. 2(a) and deflected relative to the horizontal direction in a plan view as shown in FIG. 2(b). The inner diameter of the nitrogen source nozzle 10 is not particularly limited, but is preferably between 0 mm and 30 mm, more preferably between 3 mm and 15 mm. The inclination angle of the nitrogen source nozzle 10 is not particularly limited, but is preferably between 0 degrees and less than 90 degrees, more preferably between 5 degrees and 60 degrees. The deflection angle of the nitrogen source nozzle 10 is not particularly limited, but is preferably between 0 degrees and less than 90 degrees, more preferably between 5 degrees and 45 degrees. A first heater 4 is provided around the outer periphery of the nitrogen source nozzle 10, and the nozzle is heated to the same temperature as the raw material reaction chamber 2. This heat causes NH3 in the nitrogen source nozzle 10 to decompose at a predetermined rate.

[0026] 2(b), the nitrogen source nozzle 10 has a jetting direction deflected in the same direction as the rotation direction of the substrate susceptor 12 in a plan view, thereby forming a swirling flow and improving the mixing efficiency of the group III element-containing gas and the nitrogen element-containing gas. On the other hand, the deflection direction of the nitrogen source nozzle 10 is not limited to the forward direction, and the jetting direction may be deflected in the opposite direction to the rotation direction of the substrate susceptor 12 in a plan view.

[0027] <Mixing section> In the mixing section 14, the Group III element-containing gas supplied from the raw material nozzle 8 and the nitrogen element-containing gas supplied from the nitrogen source nozzle 10 are mixed. In addition, a second heater 5 is provided on the outer periphery to maintain a desired temperature. The mixing section 14 is not particularly limited, but is preferably located above the substrate surface toward the nozzle source nozzle 10 .

[0028] <Growth Department> Growth section 16 comprises seed substrate 11, substrate susceptor 12, and rotating shaft 13. A second heater 5 is provided on the outer periphery of growth section 16, and the growth section is maintained at a desired temperature. The temperature of second heater 5 is preferably maintained at 1000°C or higher and 1400°C or lower in order to grow Group III nitride semiconductor crystal. Group III nitride semiconductor crystal grows on heated seed substrate 11 in growth section 16 by reaction between the Group III element-containing gas and the nitrogen element-containing gas mixed in mixing section 14.

[0029] The substrate susceptor 12 has a shape suitable for holding the seed substrate 11, and is not particularly limited as long as the main surface of the seed substrate 11 is positioned facing the source material nozzle 8, but it is preferable that the structure does not hinder crystal growth. If there is a structure that may grow near the crystal growth surface, polycrystalline material will adhere to it, deteriorating the uniformity of the grown film. Examples of materials that can be used include carbon, SiC-coated carbon, PG-coated carbon, PBN-coated carbon, and silicon nitride.

[0030] The rotation direction of the rotary shaft 13 is preferably the same as the deflection direction of the nitrogen source nozzle 10 described above, and the mechanism is preferably capable of controlling the rotation up to about 3000 rpm.

[0031] The unreacted Group III oxide gas, nitrogen-containing gas, and carrier gas are discharged from an outlet (not shown).

[0032] As a result, it is possible to suppress the deposition of Group III nitride semiconductor crystals on source nozzle 8 and nitrogen source nozzle 10, and to improve the mixability of the Group III element-containing gas and the nitrogen element-containing gas supplied to growth region 16. This makes it possible to homogenize the gas concentration distribution on seed substrate 11, and further increase the efficiency of transporting the source gas to seed substrate 11.

[0033] Example 1 Fig. 4 is a diagram showing the velocity vector distribution of the Group III element-containing gas and the nitrogen element-containing gas in the mixing section according to Example 1. In Example 1, the conditions for the method of manufacturing a Group III nitride semiconductor crystal according to the first embodiment were specifically set as follows, and a thermal fluid analysis was carried out by CAE (Computer Aided Engineering), as shown in Fig. 4.

[0034] The inner diameter of the source nozzle 8 was 50 mm, and the distance between the tip of the source nozzle 8 and the surface of the seed substrate was 100 mm. The inner diameter of the nitrogen source nozzle 10 was 5 mm, and the spray direction was tilted at an angle of 45 degrees from the vertical downward direction and deflected at an angle of 10 degrees counterclockwise from the radial direction toward the center in a plan view. The distance between the confluence of the nitrogen-containing gas sprayed from the nitrogen source nozzle 10 and the surface of the seed substrate 11 was 35 mm. A GaN single crystal substrate with a diameter of 100 mm was used as the seed substrate 11. Metallic Ga was placed in the source container 3 as the starting Ga source 6, and H2O gas, generated from 4 SLM of H2 gas and 20 SCCM of O2 gas, was introduced as a reactive gas through the reactive gas supply pipe 7 to generate Ga2O gas. 1 SLM of N2 gas was also introduced as a carrier gas. Meanwhile, 1 SLM of NH3 gas was introduced as a nitrogen-containing gas through the nitrogen source gas supply pipe 9, and 4 SLM of H2 gas and 4 SLM of N2 gas were introduced as carrier gases. Power was supplied to the first heater 4 located on the outer periphery of the reaction vessel 1 to reach 1150°C, and to the second heater 5 located on the outer periphery of the growth zone to reach 1200°C. The substrate susceptor 12 was rotated at 1000 RPM, and thermal fluid analysis was performed.

[0035] (Comparative Example 1) Fig. 3 is a schematic cross-sectional view showing an example of the cross-sectional configuration of Group III nitride semiconductor crystal manufacturing apparatus 40 according to Comparative Example 1. In contrast to Example 1, Comparative Example 1 is characterized by the elimination of nitrogen source nozzle 10 with an inclined / deflected spray direction. That is, in Comparative Example 1, a CAE thermal fluid analysis was carried out under the same conditions as Example 1, as shown in Fig. 5, except that no active mixing of the Group III element-containing gas sprayed from raw material nozzle 8 and the nitrogen element-containing gas sprayed from nitrogen source nozzle 10 was performed.

[0036] In Example 1 and Comparative Example 1, a thermal fluid analysis was performed to evaluate the mixing state of the Group III element-containing gas and the nitrogen element-containing gas in the mixing section based on their velocity vectors. Figures 4 and 5 show the velocity vector distributions of the Group III element-containing gas and the nitrogen element-containing gas in the mixing section 14. Because Figures 4 and 5 were originally displayed in color and converted to grayscale, the shading does not strictly correspond to high and low velocities. However, darker areas indicate higher velocities. In Example 1, as shown in Figure 4, the dark areas spread from the edges toward the center, confirming that the Group III element-containing gas and the nitrogen element-containing gas were well mixed. In Comparative Example 2, as shown in Figure 5, three dark areas were present separately, confirming that the Group III element-containing gas and the nitrogen element-containing gas were in laminar flow and not well mixed.

[0037] Next, in Example 1 and Comparative Example 1, the mixed state of the Group III element-containing gas and the nitrogen element-containing gas immediately above the substrate was quantitatively evaluated. The molar fraction of the nitrogen element-containing gas immediately above the substrate divided by the molar fraction of the Group III element-containing gas is defined as the V / III ratio. The degree of gas mixing between the nitrogen element-containing gas and the Group III element-containing gas was calculated using the following formula. The smaller the value of the degree of gas mixing between the nitrogen element-containing gas and the Group III element-containing gas, the higher the degree of mixing. Gas mixture ratio = (V / III ratio at the edge of the substrate - V / III ratio at the center of the substrate) / (average V / III ratio) 9 is Table 1 showing the gas mixing ratios of Comparative Example 1 and Example 1. As shown in Table 1, the gas mixing ratio of Comparative Example 1 was 2.34, while the gas mixing ratio of Example 1 was 0.29, confirming that inclining and deflecting the nitrogen source nozzle 10 improved the mixing ratio by approximately 8 times.

[0038] Example 2 FIG. 8 is a diagram showing the relationship between the deflection angle of the nitrogen source nozzle and the degree of gas mixing in Example 2. The deflection angle of the nitrogen source nozzle was set to 0 degrees and 30 degrees. The other configurations were the same as in Example 1, and a thermal fluid analysis was performed to verify the relationship between the deflection angle of the nitrogen source nozzle and the degree of gas mixing. As shown in Figure 8, it was confirmed that the best mixing was achieved when the deflection angle was 10 degrees.

[0039] Example 3 The rotation speed of the substrate susceptor 12 was set to 0 RPM (no rotation) and 3000 RPM. The other configurations were the same as in Example 1, and a thermal fluid analysis was performed to verify the transport efficiency of the source gas. The transport efficiency of the source gas was calculated by dividing the mass weight of GaO gas, a group III element-containing gas, and NH gas, a nitrogen element-containing gas, passing through a space up to 1 mm above the substrate by the mass flow rate of the gases emitted from the source nozzle 8 and the nitrogen source nozzle 10. In other words, the higher the source gas transport efficiency, the more GaO gas and NH gas that reach the seed substrate 11 contribute to the reaction, and therefore the higher the growth rate.

[0040] 6 is a graph showing the relationship between the rotation speed of the substrate susceptor and the source gas transport efficiency in Examples 1 and 3. It was confirmed that the source gas transport efficiency for both Ga2O gas and NH3 gas increased as the rotation speed of the substrate susceptor increased.

[0041] Example 4 The rotation speed of the substrate susceptor 12 was set to -2300 RPM and 2300 RPM. The sign of the rotation speed was set to positive when the nozzle deflection direction and the substrate rotation direction were in the same direction, and negative when the direction was opposite. The other configurations were set to the same conditions as in Example 1, and a thermal fluid analysis was performed to verify the transport efficiency of GaO gas. 10 is Table 2 showing the transport efficiency of GaO gas relative to the rotation direction of the substrate susceptor in Example 4. As shown in Table 2, when the rotation speed of the substrate susceptor was −2300 rpm, that is, when the nozzle deflection direction and the substrate rotation direction were opposite, the transport efficiency of GaO gas was 6.3%. Furthermore, when the rotation speed of the substrate susceptor was 2300 rpm, that is, when the nozzle deflection direction and the substrate rotation direction were forward, the transport efficiency of GaO gas was 8.6%. It was confirmed that when the nozzle deflection direction and the substrate rotation direction were reversed, compared with when the nozzle deflection direction and the substrate rotation direction were forward, the transport efficiency of GaO gas decreased by approximately 27%.

[0042] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Industrial Applicability]

[0043] The Group III nitride semiconductor crystal manufacturing apparatus according to the present invention can suppress the precipitation of Group III nitride semiconductor crystal on components along the source gas introduction path and improve the mixing efficiency of the Group III element-containing gas and the nitrogen element-containing gas supplied to the growth region on the substrate. This makes it possible to homogenize the gas concentration distribution on the substrate and further increase the efficiency of source gas transport to the substrate. Group III nitride semiconductor crystal obtained by the Group III nitride semiconductor crystal manufacturing apparatus according to the present invention can be used, for example, in optical devices such as light-emitting diodes and laser diodes, electronic devices such as rectifiers and bipolar transistors, and semiconductor sensors such as temperature sensors, pressure sensors, radiation sensors, and visible-ultraviolet light detectors. However, the present invention is not limited to the above-mentioned uses and can be applied in a wide range of fields. [Explanation of symbols]

[0044] 1 reaction vessel 2 Raw material reaction chamber 3 Raw material container 4. First heater 5 Second heater 6 Starting Ga source 7. Reactive gas supply pipe 8 Raw material nozzle 9. Nitrogen source gas supply pipe 10 Nitrogen source nozzle 11 types of substrate 12 Substrate susceptor 13 Rotating shaft 14 Mixing section 15 Intersection 16 Growth Department 20. III-nitride semiconductor crystal manufacturing equipment 40,50 III-nitride semiconductor crystal manufacturing equipment

Claims

1. a substrate susceptor for holding a substrate; a source nozzle that injects a group III element-containing gas toward the substrate; a nitrogen source nozzle that injects a nitrogen element-containing gas toward the substrate, the injection direction of which intersects with the injection direction of the source material nozzle in a side view, and that constitutes a mixing portion around the intersection where the Group III element-containing gas and the nitrogen element-containing gas are mixed; Equipped with A Group III nitride semiconductor crystal manufacturing apparatus, wherein the mixing section is disposed above the substrate susceptor.

2. 2. The Group III nitride semiconductor crystal manufacturing apparatus set forth in claim 1, wherein the injection port of said raw material nozzle is disposed so that the injection direction is directed vertically directly downward, and the injection port of said nitrogen source nozzle is disposed so that the injection direction is inclined with respect to the vertical direction and deflected with respect to the horizontal direction.

3. The Group III nitride semiconductor crystal manufacturing apparatus set forth in claim 1 , further comprising a rotating shaft that rotates said substrate susceptor.

4. 4. The Group III nitride semiconductor crystal manufacturing apparatus according to claim 3, wherein the deflection direction of said nitrogen source nozzle is the same as the rotation direction of said substrate.

5. 5. The Group III nitride semiconductor crystal manufacturing apparatus set forth in claim 1, further comprising heating means for heating said source nozzle, said nitrogen source nozzle, and said substrate susceptor.

6. a substrate susceptor for holding a substrate; a source nozzle that injects a group III element-containing gas toward the substrate; a nitrogen source nozzle that injects a nitrogen-containing gas toward the substrate and forms an intersection where the injection direction intersects with the injection direction of the raw material nozzle in a side view; Equipped with a group III nitride semiconductor crystal manufacturing apparatus, wherein the intersection is located between the source material nozzle and the substrate susceptor;

7. Injecting a group III element-containing gas toward a substrate; a step of spraying a nitrogen-containing gas toward the substrate to form an intersection point where the spray direction intersects with the spray direction of the raw material nozzle in a side view; mixing the nitrogen-containing gas and the group III-containing gas at the intersection; A method for producing a Group III nitride semiconductor crystal, comprising:

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