JP2019059636A - Vapor phase growth apparatus - Google Patents

Abstract

To provide techniques associated with a vapor phase growth device for compound semiconductor.SOLUTION: A vapor phase growth device 1 comprises: a reaction vessel 10; a wafer holder 11 which is arranged in the reaction vessel, and has a wafer holding surface 12a where a wafer is held with a surface of the wafer 13 substantially perpendicularly down: a first raw material gas supply pipe 21 which supplies a first raw material gas G1 into the reaction vessel, and is arranged on a lower side of the wafer holding surface; a second raw material gas supply pipe 22 which supplies a second raw material gas G2 into the reaction vessel, and is arranged on the lower side of the wafer holding surface; and a gas exhaust pipe 23 which is arranged on the lower side of the wafer holding surface. The first raw material gas supply pipe, second raw material gas supply pipe, and gas exhaust pipe are arranged extending substantially perpendicularly, and the distance between an axis A1 perpendicularly to the wafer holding surface via the center of the wafer holding surface and the gas exhaust pipe is larger than the distances between the axis, and the first raw material gas supply pipe and second raw material gas supply pipe.SELECTED DRAWING: Figure 1

Description

  The present specification discloses a technique related to a vapor phase growth apparatus for a compound semiconductor.

  There is a demand for the construction of a low-cost manufacturing method of a GaN substrate. The current GaN substrates are mainly single-wafer-type grown one by one, which is the cause of high cost. A related technique is disclosed in Patent Document 1.

Japanese Patent Application Laid-Open No. 2002-316892

  If long crystal growth of GaN is possible, a plurality of wafers can be generated from one long crystal, and thus the substrate manufacturing cost can be reduced. However, it is difficult to grow long crystals of GaN. One of the factors is that abnormal growth occurs when dust generated during crystal growth adheres to the wafer surface.

  A vapor phase growth apparatus is disclosed herein. The vapor phase growth apparatus includes a reaction container, a wafer holder disposed in the reaction container, and a wafer holder having a wafer holding surface for holding the wafer such that the wafer surface is substantially vertically downward, a first raw material A first source gas supply pipe for supplying a gas into the reaction vessel, wherein the first source gas supply pipe disposed on the lower side of the wafer holding surface and a second source gas reacting with the first source gas react with each other. A second source gas supply pipe for supplying the inside of the container, the second source gas supply pipe disposed on the lower side of the wafer holding surface, and a gas exhaust pipe for exhausting the gas in the reaction container; And a gas exhaust pipe disposed below the holding surface. Further, the first source gas supply pipe, the second source gas supply pipe, and the gas exhaust pipe are disposed so as to extend substantially in the vertical direction. Further, the distance between the gas exhaust pipe and the axis perpendicular to the wafer holding surface through the center of the wafer holding surface is larger than the distance between the axis and the first source gas supply pipe and the second source gas supply pipe. Do.

  In the vapor deposition apparatus of the present specification, the wafer surface can be maintained substantially vertically downward. Since dust generated in the reaction vessel does not fall to the wafer surface by gravity, adhesion of dust to the wafer surface can be suppressed. Further, when the wafer is evacuated upward, the dust may be attached to the surface of the wafer as the dust blown up by the evacuation drops by gravity. In the vapor phase growth apparatus of the present specification, since the gas exhaust pipe is disposed on the lower side of the wafer holding surface, the gas in the reaction vessel can be exhausted to the lower side with respect to the wafer. Since the dust is not swept up to the upper side of the wafer by the exhaust, the dust can be prevented from adhering to the wafer surface.

  The apparatus may further comprise a wafer holder, a first source gas supply pipe, a second source gas supply pipe, and a first heater disposed around the gas exhaust pipe.

  Partitions arranged on the path of the first source gas supply pipe, which are horizontally extending partitions, and a first source gas generating unit for generating the first source gas, which are arranged below the partitions The fuel cell may further include a first source gas generator connected to the inlet of the first source gas supply pipe and a second heater disposed around the first source gas generator. The first heater is disposed above the partition wall, the second heater is disposed below the partition wall, and the heating temperature of the first heater may be higher than that of the second heater. .

  The shower head further includes a plurality of first nozzles for supplying the first source gas into the reaction vessel, and a plurality of second nozzles for supplying the second source gas into the reaction vessel. It is also good. The outlets of the first source gas supply pipe and the second source gas supply pipe may be connected to the shower head. The surface of the shower head may be disposed below the wafer holding surface and at a position facing the wafer holding surface. The gas exhaust pipe may be disposed around the shower head.

  A material free of silicon and oxygen may be disposed on the surface of the shower head.

  A material containing tungsten may be disposed on the surface of the shower head.

  Each of the plurality of first nozzles may have a first central hole for discharging the first source gas, and a first peripheral hole disposed around the first central hole for discharging the specific gas. . The second nozzle may include a second central hole for discharging the second source gas, and a second peripheral hole arranged around the second central hole for discharging the specific gas. The specific gas may be a gas that does not contain oxygen and does not react with the first source gas and the second source gas.

  The reaction container may further include a specific gas supply unit for supplying a specific gas substantially vertically downward from above the wafer holder. The specific gas may be a gas that does not contain oxygen and does not react with the first source gas and the second source gas.

  The specific gas may be a gas containing at least one of hydrogen, nitrogen, helium, neon, argon and krypton.

  A material free of silicon and oxygen may be disposed on the surface of the wafer holder.

  A material containing tungsten may be disposed on the surface of the wafer holder.

It is the schematic sectional view which looked at the vapor phase growth apparatus from the side. It is the figure which looked at sectional drawing in the II-II line from the perpendicular upper part. They are a top enlarged view of a 1st nozzle, and its sectional view. It is a figure which shows temperature distribution.

<Configuration of vapor phase growth system>
FIG. 1 shows a schematic cross-sectional view of a vapor phase growth apparatus 1 according to the technology of the present specification as viewed from the side. The vapor phase growth apparatus 1 is an example of an apparatus configuration for carrying out the HVPE (Hydride Vapor Phase Epitaxy) method. The vapor phase growth apparatus 1 includes a reaction vessel 10. The reaction vessel 10 has a cylindrical shape. The reaction vessel 10 may be made of quartz. A source gas supply unit 20 and a wafer holder 11 are disposed inside the reaction container 10.

The structure of the source gas supply unit 20 will be described. The source gas supply unit 20 is a cylindrical member. The source gas supply unit 20 includes a cylindrical cover 24. At the upper end of the cover 24, a disk-like shower head 50 is disposed. At the lower part of the source gas supply unit 20, the inlet of the HCl gas supply pipe 25 and the inlet of the second source gas supply pipe 22 are disposed. A gas containing HCl is supplied to the inlet of the HCl gas supply pipe 25. The outlet of the HCl gas supply pipe 25 is connected to the first source gas generator 41. The first source gas generation unit 41 stores metallic gallium inside. The first source gas generation unit 41 is a portion that generates a first source gas G1 containing GaCl. The first source gas supply pipe 21 is a pipe that supplies the first source gas G1. The inlet of the first source gas supply pipe 21 is connected to the first source gas generator 41. The outlet of the first source gas supply pipe 21 is connected to the shower head 50. A gas containing the second source gas G2 is supplied to the inlet of the second source gas supply pipe 22. The second source gas G2 is a gas containing NH ₃ . The outlet of the second source gas supply pipe 22 is connected to the shower head 50.

  The first source gas supply pipe 21 and the second source gas supply pipe 22 are arranged to extend in the vertical direction (that is, the z-axis direction in FIG. 1). A partition 42 is disposed on the path of the first source gas supply pipe 21 and the second source gas supply pipe 22. The partition wall 42 is a quartz plate extending in the horizontal direction in the cover 24. The space in the cover 24 is vertically separated by the partition wall 42.

  The shower head 50 is a portion for discharging the first source gas G1 and the second source gas G2 to the vicinity of the surface of the wafer 13. The first source gas G1 and the second source gas G2 discharged from the shower head 50 flow vertically upward in the reaction container 10 in the direction of the arrow Y1.

  The structure of the shower head 50 will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. A plurality of first nozzles 51 for discharging a first source gas G1 and a plurality of second nozzles 52 for discharging a second source gas G2 are disposed on the surface of the shower head 50. By discharging the first source gas G1 and the second source gas G2 from a large number of nozzles, the amount of gas supplied to the surface of the wafer 13 can be made uniform within the wafer surface. Therefore, it is possible to suppress the wafer in-plane variation of the grown GaN crystal film thickness.

  A material free of silicon and oxygen is disposed on the surface of the shower head 50. The material disposed on the surface of the shower head 50 is preferably a material that is stable in a high temperature environment and in an ammonia atmosphere. In the present embodiment, a material containing tungsten is disposed on the surface of the shower head 50. As a first effect, this can suppress the deposition of polycrystalline GaN on the surface of the shower head 50. This is due to the catalytic effect of tungsten. As a second effect, the temperature on the surface of the shower head 50 can be made uniform. This is because, since tungsten is a metal having a high thermal conductivity, when the outer periphery of the shower head 50 is heated by the first heater 31, heat can be transmitted to the center of the shower head 50. As a third effect, it is possible to prevent the occurrence of impurities of oxygen and silicon from the shower head 50. This is because the surface of the shower head 50 is covered with tungsten which is a material free of silicon and oxygen.

  Further, as shown in FIG. 2, the upper surface of the cover 24 is disposed on the outer periphery of the shower head 50. Therefore, the upper surface of the cover 24 functions as a part of the shower head 50. A material containing tungsten may be disposed on the upper surface of the cover 24 as well. Thereby, precipitation of polycrystalline GaN on the upper surface of the cover 24 can be suppressed.

  FIG. 3 shows an enlarged top view of the first nozzle 51 and a cross-sectional view thereof. The first nozzle 51 includes a central hole 54 for discharging the first source gas G1, and a peripheral hole 55 disposed around the central hole 54 for discharging the specific gas G3. The specific gas G3 is a gas that does not contain oxygen, and is a gas that does not react with the first source gas G1 and the second source gas G2. As a specific example, the specific gas G3 is a gas containing at least one of hydrogen, nitrogen, helium, neon, argon, and krypton. For example, unexpected reaction occurs by using argon which is an inert gas not containing N which is a constituent element of a nitride semiconductor, or helium which is an inert gas which does not contain H which is a constituent element of the second source gas G2. May be suppressed. Moreover, it is possible to improve the function of the air curtain mentioned later by including the argon whose atomic radius is larger than nitrogen in specific gas G3. The cross sectional structure of the second nozzle 52 is also similar to that of the first nozzle 51 described in FIG. That is, it has a central hole for discharging the second source gas G2, and a peripheral hole disposed around the central hole for discharging the specific gas G3.

  Thus, a gas layer of the specific gas G3 may be formed around the first source gas G1 discharged from the first nozzle 51 and around the second source gas G2 discharged from the second nozzle 52. it can. The gas layer of the specific gas G3 functions as an air curtain in the vicinity of the surface 50a of the shower head 50, but does not function as an air curtain because it is sufficiently diffused in the vicinity of the surface of the wafer 13. Therefore, the first source gas G1 and the second source gas G2 are not mixed near the surface 50a of the shower head 50, but are mixed near the surface of the wafer 13. As a result, precipitation of polycrystalline GaN on the surface 50 a of the shower head 50 can be suppressed, and a GaN single crystal can be grown on the surface of the wafer 13.

  The number and arrangement layout of each of the first nozzle 51 and the second nozzle 52 can be freely set based on various parameters such as the required supply amount of gas and the influence on the gas flow state. It is also possible to divide the surface of the shower head 50 into a plurality of zones and to control the gas flow rate individually in each zone. Further, the shapes of the first nozzle 51 and the second nozzle 52 may be various. It may be a circle, a polygon, a slit shape, or the like.

  Around the source gas supply unit 20, a gas exhaust pipe 23 for exhausting the gas in the reaction vessel 10 is configured. This will be described with reference to FIG. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. Inside the cylindrical reaction vessel 10, a cylindrical source gas supply unit 20 is further disposed. Thus, an annular gap is formed between the inner wall of the reaction vessel 10 and the outer wall of the cover 24 of the raw material gas supply unit 20. The annular gap functions as the gas exhaust pipe 23. That is, the gas exhaust pipe 23 is disposed to extend vertically downward (that is, in the z-axis direction in FIG. 2) along the outer wall of the raw material gas supply unit 20 and the inner wall of the reaction vessel 10. Thus, the gas exhaust pipe 23 can be disposed so as to surround the outer periphery of the shower head 50, the first source gas supply pipe 21, and the second source gas supply pipe 22. In other words, the following relationships hold in the first source gas supply pipe 21, the second source gas supply pipe 22, and the gas exhaust pipe 23. Assuming an axis A1 (see FIG. 1) perpendicular to the wafer holding surface 12a through the center of the wafer holding surface 12a. The distance between the axis A1 and the gas exhaust pipe 23 is It is larger than the distance to the second source gas supply pipe. "

  Further, the inlet 23 a of the gas exhaust pipe 23 can be positioned on the side surface of the shower head 50. Therefore, as shown by arrow Y2 in FIG. 1, the first source gas G1 and the second source gas G2 used for GaN crystal growth on the surface of the wafer 13 are exhausted in the lateral direction of the shower head 50 and downward of the wafer 13. It can be done. At the lower end of the reaction vessel 10, an outlet 23b of the gas exhaust pipe 23 is disposed. The gas sucked from the inlet 23a of the gas exhaust pipe 23 is discharged from the outlet 23b to the vent line.

  Further, by positioning the inlet 23a of the gas exhaust pipe 23 on the side of the shower head 50 and positioning the outlet 23b at the lower end of the reaction vessel 10, the distance from the inlet 23a to the outlet 23b can be sufficiently secured. Therefore, even when the outlet 23 b is provided in a part of the annular gas exhaust pipe 23, the gas can be uniformly sucked from the outer periphery of the shower head 50 at the inlet 23 a. Thereby, it is possible to prevent the partial flow of gas.

  The wafer holder 11 is disposed in the reaction container 10. The wafer holder 11 includes a wafer holder 12 on the lower surface. The wafer holder 12 is made of a material having a high thermal conductivity. In the present embodiment, the wafer holding unit 12 is a SiC crystal. Thereby, the temperature on the surface of the wafer 13 can be made uniform. This is because, since SiC is a material having high thermal conductivity, when the outer periphery of the wafer 13 is heated by the first heater 31, heat can be transmitted to the center of the wafer 13.

  A wafer holding surface 12 a is disposed on the lower surface of the wafer holding unit 12. The wafer holding surface 12a holds the wafer 13 so that the surface of the wafer 13 is substantially vertically downward. Here, “substantially vertically downward” is a direction in which dust dropped by gravity does not fall on the wafer surface. Therefore, “substantially vertically downward” is not limited to the aspect in which the normal of the wafer coincides with the vertically downward direction. The concept is that the normal to the wafer includes an inclination of up to 45 degrees with respect to the vertically downward direction. The surface of the shower head 50 is disposed below the wafer holding surface 12 a of the wafer holder 11 and at a position facing the wafer holding surface 12 a.

  A material free of silicon and oxygen is disposed on the surface of the wafer holder 11. In the present embodiment, a material containing tungsten is disposed on the surface of the wafer holder 11. As a result, the effect of suppressing the deposition of polycrystalline GaN on the surface of the wafer holder 11, the effect of making the surface temperature of the wafer holder 11 uniform, and the effect of preventing the generation of impurities of oxygen and silicon can be obtained. The reason is the same as the contents described above for the shower head 50.

  The upper end of the wafer holder 11 is connected to the lower end of the rotating shaft 14. The upper end portion of the rotating shaft 14 protrudes to the outside of the reaction vessel 10. The upper end portion of the rotary shaft 14 is connected to the drive mechanism 15. Thus, the wafer holder 11 can be rotated and moved up and down in the reaction vessel 10.

  At the upper part of the reaction vessel 10, a specified gas supply pipe 16 is provided. The specific gas G3 is supplied to the inlet of the specific gas supply pipe 16. The specified gas G3 flows vertically downward from above the wafer holder 11 and is sucked into the inlet 23a of the gas exhaust pipe 23, as shown by arrow Y3 in FIG. Thereby, the downflow can be generated by the specific gas G3.

  Explain the effect. The downflow of the specific gas G3 can prevent the first source gas G1, the second source gas G2, the reaction product, and the like from rising above the wafer holder 11. Thus, the upper portion of the wafer holder 11 is not contaminated by the polycrystalline GaN or the reaction product. It is possible to prevent the occurrence of dust falling from above the wafer holder 11. Further, since the contamination of the rotating shaft 14 disposed on the upper portion of the wafer holder 11 and the rotation mechanism thereof can be prevented, the rotating operation of the wafer holder 11 can be stabilized.

  A first heater 31 and a second heater 32 are disposed outside the reaction vessel 10. The first heater 31 is disposed above the partition wall 42. The first heater 31 is disposed to surround the wafer holder 11, the first source gas supply pipe 21, the second source gas supply pipe 22, and the gas exhaust pipe 23. The second heater 32 is disposed below the partition wall 42. The second heater 32 is disposed to surround the first source gas generation unit 41.

<Gas phase growth method>
A method of vapor phase growing a GaN layer on the wafer 13 by the HVPE method will be described. An example of atmosphere growth conditions is listed. The supply amounts of GaCl in the first source gas G1 and NH ₃ in the second source gas G2 were set to a molar ratio of 1:20. The pressure in the reaction vessel 10 was 1000 hPa, and the pressure at the outlet 23b of the gas exhaust pipe 23 was 990 hPa.

  As shown in FIG. 1, the partition wall 42 is disposed in the vicinity of the boundary between the region R1 in which the first heater 31 is disposed and the region R2 in which the second heater 32 is disposed. The partition 42 functions as a heat insulating material. Therefore, the heating temperature can be individually controlled for each region with the partition wall 42 as a boundary. In the present embodiment, the first heater 31 has a heating temperature higher than that of the second heater 32. Thereby, a temperature distribution as shown in FIG. 4 can be realized. In FIG. 4, the horizontal axis indicates the positional relationship along the vertical direction of each member, and the vertical axis indicates the temperature. The first heater 31 can heat the wafer 13 to a temperature (1050 ± 50 ° C.) sufficient for GaN crystal growth. In addition, the first source gas generation unit 41 can be heated by the second heater 32 to a temperature (750 ° C. or more) necessary for generation of GaCl. There is a temperature difference of about 300 ° C. between the heating temperature of the wafer 13 and the first source gas generation unit 41, but the partition wall 42 functions as a heat insulating material to maintain the temperature difference between the wafer 13 and the first The distance to the source gas generating unit 41 can be shortened. Thus, the vapor phase growth apparatus 1 can be miniaturized.

<Effect>
In the HVPE method, it is difficult to grow long crystals (also referred to as thick film crystals) on the c-plane of GaN. This is because it is difficult to suppress the occurrence of abnormal growth. The following three are mentioned as an example of a factor of generating of abnormal growth. The first factor is that dust generated in the reaction vessel falls on the wafer surface by gravity. The second factor is that the deposition of polycrystals of GaN on the first nozzle 51 and the second nozzle 52 of the shower head 50 causes clogging of the gas pipe and changes in gas flow. The third factor is that the ammonium chloride powder, which is a by-product, is clogged in the gas exhaust pipe 23 or the like to cause a gas flow change.

  As a countermeasure against the first factor, in the wafer holder 11 of the present specification, the surface of the wafer 13 can be held substantially vertically downward. Dust generated in the reaction container 10 does not fall to the surface of the wafer 13 by gravity, so that adhesion of dust to the surface of the wafer 13 can be suppressed. In the case of exhausting the wafer 13 upward, the dust may be attached to the surface of the wafer 13 by gravity falling on the upper side of the wafer. In the vapor phase growth apparatus 1 of the present specification, since the gas exhaust pipe 23 is disposed below the wafer holding surface 12 a, the gas in the reaction vessel 10 can be exhausted downward relative to the wafer 13. . Since the dust is not blown up to the upper side of the wafer 13 by the exhaust, adhesion of the dust to the surface of the wafer 13 can be suppressed.

  As a measure for the second factor, a material containing tungsten is disposed on the surface of the shower head 50. Further, a surrounding hole 55 for discharging the specific gas G3 is disposed around the center hole 54 for discharging the first source gas G1 and the second source gas G2. Thereby, the deposition of the polycrystalline GaN on the surface of the shower head 50 can be prevented by the catalytic effect and the air curtain function.

  As a countermeasure for the third factor, the first heater 31 is disposed so as to surround the wafer holder 11, the first source gas supply pipe 21, the second source gas supply pipe 22, and the gas exhaust pipe 23. Thus, when the wafer 13 held by the wafer holder 11 is heated, the gas exhaust pipe 23 can be simultaneously heated. The heating temperature (about 1050 ° C.) of wafer 13 is sufficiently higher than the temperature (about 200 ° C.) at which ammonium chloride powder as a by-product is generated in gas exhaust pipe 23. Ammonium chloride powder never clogs.

<Modification>
Although the embodiments of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The art set forth in the claims includes various variations and modifications of the specific examples illustrated above.

  The area in which the heater is disposed is not limited to the aspect of dividing into two of the areas R1 and R2, and may be divided into three or more. Thereby, the temperatures of the wafer 13, the shower head 50, the first source gas generation unit 41, and the like can be more precisely controlled. For example, the temperature of the portion where it is not desired to precipitate the GaN polycrystal may be higher than the temperature of the surface of the wafer 13. Specifically, the heaters disposed around the wafer 13 and the heaters disposed around the shower head 50 may be disposed separately. By raising the temperature of the surface 50 a of the shower head 50 to about 50 ° C. with respect to the temperature of the surface of the wafer 13, it becomes possible to prevent the deposition of GaN polycrystal on the surface 50 a.

  The temperature sufficient for GaN crystal growth was described as 1050 ± 50 ° C. In addition, the temperature required to generate GaCl was described as 750 ° C. or higher. However, these temperatures are exemplary. For example, a temperature sufficient for GaN crystal growth may be in the range of 1050 ° C. ± 100 ° C.

  The shape of the gas exhaust pipe 23 is not limited to the shape of the present embodiment, and may be various shapes. For example, a plurality of thin tubes may be disposed on the outer periphery of the shower head 50.

  HCl may be added to the specific gas G3 discharged from the shower head 50. This makes it possible to decompose the polycrystalline GaN deposited on the surface of the shower head 50 and the nozzles.

  The number and the arrangement of the first source gas supply pipe 21, the second source gas supply pipe 22, and the HCl gas supply pipe 25 shown in FIG. 1 are an example, and the present invention is not limited to this embodiment.

  Although tungsten has been described as a material from which metal catalytic effects can be obtained, the present invention is not limited to this material. Other metals such as molybdenum, ruthenium, iron, nickel, platinum, iridium, palladium, rhodium and the like can also be used.

  The vent line may be provided with a pump (not shown). The pressure in the gas exhaust pipe 23 may be negative with respect to the pressure near the surface of the wafer 13. As a result, it is possible to more smoothly exhaust the lateral direction of the shower head 50 and the downward direction of the wafer 13 as shown by the arrow Y2 in FIG.

The techniques described herein are applicable not only to the HVPE method but also to various growth methods. For example, the present invention can be applied to the MOVPE (Metal Organic Vapor Phase Epitaxy) method. In this case, trimethyl gallium (Ga (CH ₃ ) ₃ ) or the like may be used as the first source gas G1.

The technology described herein is applicable to crystal growth of various compound semiconductors, not limited to GaN. For example, it can be applied to the growth of a GaAs crystal. In this case, arsine (AsH ₅ ) may be used as the second source gas G2.

The first source gas G1 and the second source gas G2 may flow together with a carrier gas such as H ₂ or N ₂ .

  The technical elements described in the present specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims at the time of application. In addition, the techniques exemplified in the present specification or the drawings can simultaneously achieve a plurality of purposes, and achieving one of the purposes itself has technical utility.

The central hole 54 is an example of a first central hole. The surrounding hole 55 is an example of a first surrounding hole.
The specific gas supply pipe 16 is an example of a specific gas supply unit.

  1: Vapor phase growth apparatus, 10: Reaction vessel, 11: Wafer holder, 12a: Wafer holding surface, 21: First source gas supply pipe, 22: Second source gas supply pipe, 23: Gas exhaust pipe, 31: First Heater, 32: Second heater, 41: First source gas generator, 42: Partition, 50: Shower head

Claims (11)

A reaction vessel,
A wafer holder disposed in the reaction vessel, the wafer holder having a wafer holding surface for holding the wafer such that the wafer surface is substantially vertically facing downward;
A first source gas supply pipe for supplying a first source gas into the reaction vessel, the first source gas supply pipe disposed below the wafer holding surface;
A second source gas supply pipe for supplying a second source gas that reacts with the first source gas into the reaction container, the second source gas supply pipe being disposed below the wafer holding surface ,
A gas exhaust pipe for exhausting a gas in the reaction vessel, the gas exhaust pipe disposed below the wafer holding surface;
Equipped with
The first source gas supply pipe, the second source gas supply pipe, and the gas exhaust pipe are disposed so as to extend substantially in the vertical direction,
The distance between the gas exhaust pipe and the axis perpendicular to the wafer holding surface through the center of the wafer holding surface is larger than the distance between the axis and the first source gas supply pipe and the second source gas supply pipe What is claimed is: 1. A vapor phase growth apparatus for compound semiconductors.   The vapor deposition according to claim 1, further comprising a first heater disposed around the wafer holder, the first source gas supply pipe, the second source gas supply pipe, and the gas exhaust pipe. apparatus. A partition disposed on a path of the first source gas supply pipe, the partition extending in the horizontal direction;
A first source gas generating unit that generates the first source gas, the first source gas generating unit being disposed below the partition and connected to an inlet of the first source gas supply pipe When,
A second heater disposed around the first source gas generator;
And further
The first heater is disposed above the partition, and
The second heater is disposed below the partition wall, and
The vapor deposition apparatus according to claim 2, wherein the heating temperature of the first heater is higher than that of the second heater. A shower head having a plurality of first nozzles for supplying the first source gas into the reaction container, and a plurality of second nozzles for supplying the second source gas into the reaction container. In addition,
The outlets of the first source gas supply pipe and the second source gas supply pipe are connected to the shower head,
The surface of the shower head is disposed below the wafer holding surface and at a position facing the wafer holding surface,
The vapor growth apparatus according to any one of claims 1 to 3, wherein the gas exhaust pipe is disposed around the shower head.   The vapor growth apparatus according to claim 4, wherein a material free of silicon and oxygen is disposed on a surface of the shower head.   The vapor phase growth apparatus according to claim 4 or 5, wherein a material containing tungsten is disposed on the surface of the shower head. Each of the plurality of first nozzles is
A first center hole for discharging the first source gas;
A first surrounding hole disposed around the first central hole and discharging a specific gas;
Equipped with
The second nozzle is
A second center hole for discharging the second source gas;
A second surrounding hole disposed around the second central hole and discharging the specific gas;
Equipped with
The gas phase according to any one of claims 4 to 6, wherein the specific gas is a gas which does not contain oxygen and which does not react with the first source gas and the second source gas. Growth equipment. The reaction container further comprises a specific gas supply unit for supplying a specific gas substantially vertically downward from above the wafer holder in the reaction container,
The gas phase according to any one of claims 1 to 7, wherein the specific gas is a gas which does not contain oxygen and which does not react with the first source gas and the second source gas. Growth equipment.   9. The vapor phase growth apparatus according to claim 8, wherein the specific gas is a gas containing at least one of hydrogen, nitrogen, helium, neon, argon and krypton.   The vapor phase growth apparatus according to any one of claims 1 to 9, wherein a material free of silicon and oxygen is disposed on the surface of the wafer holder.   The vapor phase growth apparatus according to any one of claims 1 to 10, wherein a material containing tungsten is disposed on the surface of the wafer holder.

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