JP2014003251A - Vapor growth device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor growth device which can suppress falling of a bearing ball even during vapor phase growth of high temperature (e.g., 1000°C or higher) where a reaction gas exists, in the vapor growth device having a substrate rotary mechanism including a rotary member being held rotatably for a base, via a plurality of bearing balls held by a ring-shaped bearing ball holder.SOLUTION: In the vapor growth device, a plurality of recesses for housing bearing balls are provided on an inner peripheral side of a ring-shaped bearing ball holder.

Description

  The present invention relates to a vapor phase growth apparatus, and more particularly, to a vapor phase growth apparatus having a substrate rotation mechanism.

As a method for growing a crystal film on a substrate, there is a chemical vapor deposition (CVD) method or the like, and a CVD method involving substrate heating is known as a thermal CVD method or the like. In recent years, vapor phase growth performed by heating a substrate under high temperature conditions (for example, 1000 ° C. or more) is increasing, and vapor phase growth of a group III nitride semiconductor for producing a blue or ultraviolet LED or a blue or ultraviolet laser diode. Is one of them. For example, the growth of a group III nitride semiconductor crystal film was heated to a high temperature of 1000 ° C. or higher using an organic metal gas such as trimethylgallium, trimethylindium, or trimethylaluminum as a group III metal source and ammonia as a nitrogen source. In some cases, the thermal CVD method is used in which a crystal film is vapor-phase grown on a substrate such as silicon (Si), sapphire (Al ₂ O ₃ ), or gallium nitride (GaN).

  As the vapor phase growth apparatus, there are an apparatus in which the crystal growth surface of the substrate is arranged upward (face-up type) and an apparatus in which the crystal growth surface of the substrate is arranged downward (face-down type). In addition, there is a vapor phase growth apparatus that grows a crystal film on one substrate per batch, but there is also a vapor phase growth apparatus that grows a crystal film on multiple substrates per batch in order to improve productivity. Are known. In these vapor phase growth apparatuses, a crystal film having a uniform film thickness and film quality can be grown on the substrate surface by rotating the substrate. In addition, by rotating and revolving the substrate, a uniform film thickness and film quality can be obtained not only within the same substrate plane but also between the substrates. In such a vapor phase growth apparatus, the substrate rotation mechanism and the revolution mechanism may be provided separately so that the ratio between the rotation speed and the revolution speed of the substrate can be appropriately changed in order to optimize the film forming conditions. Desirably, for example, in the vapor phase growth apparatus described in Patent Document 1, the substrate rotation mechanism and the substrate revolution mechanism are provided separately.

In the vapor phase growth apparatus provided with the substrate rotation mechanism, it is desirable that the substrate is rotatably held. For example, in the vapor phase growth apparatus described in Patent Document 2, a plurality of substrate holders holding the substrate are: The susceptor is rotatably held by a susceptor, and the susceptor is rotatably held by a susceptor holding plate. In such a substrate rotating mechanism, a bearing is often used as means for rotatably holding a rotating member (substrate holder and susceptor) by a base (susceptor and susceptor holding plate). As in a vapor phase growth apparatus, a configuration is often used in which each rotating member is rotatably held by sandwiching a bearing ball by grooves provided on the lower surface of the rotating member and the upper surface of the base.
JP 2004-241460 A JP 2009-99770 A

Conventionally, in a vapor phase growth apparatus having such a substrate rotating mechanism, the bearing ball disposed in the groove is only held by being sandwiched between the rotating member and the base, and therefore, due to eccentricity of rotation and reactive gas. There is a problem that the ball is likely to drop out of the groove due to deterioration of the bearing, dimensional change of the constituent material due to a sudden temperature rise, vibration or friction. For this reason, there has been a demand for a vapor phase growth apparatus that can prevent bearing balls from dropping even during vapor phase growth in which a reactive gas is present and a high temperature environment.
That is, the problem to be solved by the present invention is to provide a vapor phase growth apparatus capable of suppressing bearing ball dropout even during vapor phase growth in which a reactive gas exists and is in a high temperature environment (for example, 1000 ° C. or higher). That is.

  As a result of intensive studies to solve such problems, the inventors of the present invention are held rotatably with respect to the base via a plurality of bearing balls held by a ring-shaped bearing ball holder. In a vapor phase growth apparatus having a substrate rotation mechanism provided with a rotating member, it has been found that the above-mentioned problems can be solved by providing a plurality of recesses for receiving bearing balls on the inner peripheral side of the ring-shaped bearing ball holder. The vapor phase growth apparatus of the present invention has been reached.

  That is, the present invention is a vapor phase growth apparatus having a substrate rotating mechanism provided with a rotating member that is rotatably held with respect to a base via a plurality of bearing balls held by a ring-shaped bearing ball holder. The ring-shaped bearing ball holder is provided with a plurality of recesses for housing the bearing balls on the inner peripheral side.

In the vapor phase growth apparatus of the present invention, the rotating member is rotatably held with respect to the base via the plurality of bearing balls held by the ring-shaped bearing ball holder, so that the rotating member is being rotated. Dropping of the bearing ball is suppressed. Furthermore, since the ring-shaped bearing ball holder is provided with a plurality of recesses for housing the bearing balls on the inner peripheral side, the falling off of the bearing balls due to the horizontal force caused by rotational eccentricity is effectively suppressed. The
Further, in the vapor phase growth apparatus of the present invention, by setting the length of the protrusion of the recess smaller than the diameter of the bearing ball, the protrusion does not come into contact with the side surface of the rotating member or the base during the rotation of the rotating member. The rotating member can be rotated with a small rotational driving force.

The present invention is applied to a vapor phase growth apparatus having a substrate rotation mechanism provided with a rotating member that is rotatably held with respect to a base via a plurality of bearing balls held by a ring-shaped bearing ball holder. Is done. Hereinafter, although this invention is demonstrated in detail based on FIGS. 1-6, this invention is not limited by these.
1 is a vertical sectional view showing an example of the vapor phase growth apparatus of the present invention, and FIG. 2 is an enlarged view of a portion A in FIG. 3 is a cross-sectional configuration view taken along the line BB in FIG. 1, and FIG. 4 is a cross-sectional configuration diagram taken along the line CC in FIG. 5 is a perspective view from above showing a bearing ball holder that can hold a plurality of bearing balls used to rotatably hold a substrate holder rotating plate in the vapor phase growth apparatus of FIG. FIG. 6 is an enlarged view of a part D in FIG. 5.

  At least one of the rotating members provided in the substrate rotating mechanism of the vapor phase growth apparatus of the present invention is rotatably held with respect to the base via a plurality of bearing balls held by a ring-shaped bearing ball holder. The ring-shaped bearing ball holder includes a plurality of recesses for housing the bearing balls on the inner peripheral side. The rotating member used in the present invention is selected from a substrate holder that holds a substrate, a substrate holder rotating plate that transmits a rotation driving force from the substrate holder rotation driver to the substrate holder, and a susceptor that holds a plurality of substrate holders. Rotating member.

In the vapor phase growth apparatus of the present invention, when the substrate holder rotating plate is rotated by the rotational driving force transmitted from the substrate holder rotating driving shaft, for example, if the substrate holder rotating driving shaft is slightly eccentric, Since the bearing ball easily falls off the groove due to the generated horizontal force, the substrate holder rotating plate is particularly preferably used with the bearing ball holder in preference to the other rotating members.
The rotating member used in the present invention preferably has a disk shape or a ring shape, but is not limited to such a shape. The rotating member used in the present invention is preferably provided with a gear on the outer periphery or the inner periphery in order to transmit the rotational driving force or receive the rotational driving force. It is not limited to the structure provided with the gear as a means.

  The substrate rotation mechanism of the present invention includes a mechanism including a substrate rotation mechanism and a substrate revolution mechanism, and examples thereof include a mechanism provided in the vapor phase growth apparatus of FIGS. In this substrate rotation mechanism, a substrate holder 3, a substrate holder rotation plate 6, and a susceptor 9 are provided as rotating members, and the susceptor 9 and the susceptor holding plate 18 are provided so as to function as a base. The substrate holder rotating plate 6 is held by the susceptor 9 and the susceptor 9 is held by the susceptor holding plate 18 via a plurality of bearing balls 2 held by the ring-shaped bearing ball holder 1, respectively. . The substrate rotation mechanism is provided around the substrate holder rotation plate 6 from the substrate holder rotation drive 8 via the substrate holder rotation plate 6 provided at the center of the reaction furnace 12 and having a gear 6b on the outer periphery. The substrate holder 3 is rotated by transmitting a rotational driving force to a plurality of substrate holders 3 having 3a. The substrate revolving mechanism has a configuration in which the susceptor 9 is rotated by transmitting a rotational driving force to the susceptor 9 having the gear 9aa on the outer periphery via the susceptor rotating plate 17 having the gear 17a on the outer periphery. .

  In the vapor phase growth apparatus of the present invention, the substrate holder is preferably set so as to hold one substrate having a diameter of usually 2 inches or more, preferably 3 inches or more, more preferably 4 inches or more. However, it is not limited to such a setting. The substrate holder preferably has a disk shape, a ring shape, or a cylindrical shape, but is not limited to such a shape.

  1-4, each substrate holder 3 is sandwiched by bearing grooves (3b, 9ab) carved in the lower surface of the substrate holder 3 and the upper surface of the susceptor 9, and the same bearing as in FIG. It is rotatably held with respect to the susceptor 9 via a plurality of bearing balls 2 held by a ball holder. This bearing ball holder is a bearing ball holder similar to that shown in FIG. 5, but the number and dimensions of the bearing balls and recesses are appropriately changed. Each substrate holder 3 has a ring shape or a cylindrical shape, and holds the substrate 5 such that the crystal growth surface of the substrate 5 faces downward. The substrate holder used in the present invention is such a substrate holder. The substrate holder is not limited to the substrate holder that holds the substrate downward, and may be a substrate holder that holds the substrate upward or horizontally, for example.

  In the vapor phase growth apparatus of the present invention, when rotating a plurality of substrate holders, for example, a substrate holder rotating plate having a gear on the outer periphery is provided at the center of the reaction furnace, and the substrate holder is interposed via the substrate holder rotating plate. The substrate and the substrate holder can be rotated by transmitting the rotational driving force from the rotation driver to a plurality of substrate holders provided around the substrate holder rotating plate and having gears on the outer periphery.

  In the vapor phase growth apparatus of the present invention, the substrate holder rotating plate preferably has a disk shape, a ring shape, or a cylindrical shape, but is not limited to such a shape. In addition, the substrate holder rotating plate is particularly preferably a disk shape having a diameter of 100 to 500 mm and a thickness of 3 to 20 mm, but is not limited to such a size and shape. 1-4, the disc-shaped substrate holder rotating plate 6 is sandwiched between bearing grooves (6c, 9ba) carved on the lower surface of the substrate holder rotating plate 6 and the upper surface of the susceptor 9, respectively. The bearing ball holder 1 is held by a plurality of bearing balls 2 so as to be rotatable with respect to the susceptor 9.

  In the present invention, the base for holding the rotating member preferably has a disk shape, a ring shape, or a cylindrical shape, but is not limited to such a shape. For example, in the vapor phase growth apparatus of FIGS. 1 to 4, a disk-shaped susceptor 9 is provided as a base for holding the substrate holder 3 and the substrate holder rotating plate 6, and a ring-shaped susceptor is provided as a base for holding the susceptor 9. A holding plate 18 is provided. Further, the rotating member used in the present invention can also have a function as a base for holding other rotating members, like the susceptor 9 in the vapor phase growth apparatus of FIGS.

  In the vapor phase growth apparatus of the present invention, the susceptor preferably has a disk shape, a ring shape, or a cylindrical shape, but is not limited to such a shape. In addition, the susceptor has a disk shape with an outer diameter of 300 to 1000 mm and a thickness of 5 to 30 mm, and it is particularly preferable that 6 to 15 substrate holders can be held. There is no limit.

  1-4, the susceptor 9 is sandwiched by bearing grooves (9ab ′, 18a) carved on the lower surface of the disc-shaped susceptor 9 and the upper surface of the ring-shaped susceptor holding plate 18, respectively. 5 is rotatably held with respect to the susceptor holding plate 18 via a plurality of bearing balls 2 held by a bearing ball holder similar to 5. This bearing ball holder is a bearing ball holder similar to that shown in FIG. 5, but the number and dimensions of the bearing balls and recesses are appropriately changed.

  In the vapor phase growth apparatus of the present invention, the susceptor may be composed of a plurality of separable members for the purpose of facilitating maintenance, for example, a disk-shaped susceptor may be formed into a disk-shaped member and a ring-shaped member. It can be comprised from a member. In this case, the susceptor can be formed by installing the disk-shaped member in the space of the ring-shaped member. In addition, a configuration in which the substrate holder rotating plate is held by a disk-shaped member and a plurality of substrate holders is held by a ring-shaped member is particularly preferable, but the configuration is not limited thereto. The disk-shaped member constituting the susceptor is preferably a disk having a diameter of 100 to 500 mm and a thickness of 3 to 20 mm, but is not limited to such a size. The ring-shaped member constituting the susceptor has a ring shape with an outer diameter of 300 to 1000 mm, an inner diameter of 100 to 500 mm, and a thickness of 5 to 30 mm, and is preferably capable of holding 6 to 15 substrate holders. The number of substrate holders is not limited.

  1-4, the ring-shaped member 9a and the disk-shaped member 9b constituting the susceptor 9 are provided as separate separable members, and are provided on the outer periphery of the disk-shaped member 9b toward the periphery. The disc-shaped member 9b is held by the ring-shaped member 9a and the susceptor 9 is formed by superimposing the projecting portion formed on the inner peripheral lower portion of the ring-shaped member 9a toward the central portion. Yes. The bearing ball holder used in the present invention has a ring shape as shown in FIG. Such a bearing ball holder may be configured as an integral member that cannot be divided, or may be configured from a plurality of members that can be divided. In addition, although it is preferable that the diameter of the bearing ball used for this invention is 1-10 mm, it is not limited to such a magnitude | size.

  A plurality of recesses for receiving bearing balls are provided on the inner peripheral side of the bearing ball holder used in the present invention. For example, as shown in FIGS. 5 and 6, a recess for housing the bearing ball is formed by adjacent protrusions provided on the inner peripheral side of the bearing ball holder. As described above, each recess can be formed by a notch formed in the radial direction on the inner periphery of the bearing ball holder from the upper surface to the lower surface of the bearing ball holder. Each recess is preferably a recess that can accommodate one bearing ball. In addition, the recesses are preferably provided at equal intervals in the circumferential direction of the ring constituting the bearing ball holder so that the rotating member can be held more stably, but are not limited to equal intervals. .

  In the bearing ball holder used in the present invention, the recess has an insertion port into which the bearing ball can be inserted on the inner peripheral side of the bearing ball holder, and the diameter of the insertion port of the recess is set larger than the diameter of the bearing ball. The By setting the diameter of the insertion port of the recess larger than the diameter of the bearing ball, the bearing ball 2 can be stored deeply in the recess 1a as shown in FIGS. Can be suppressed. The diameter of the insertion port of the recess is preferably 0.1 to 1 mm larger than the diameter of the bearing ball, but is not limited to such a diameter.

  Further, in the bearing ball holder used in the present invention, the recess is constituted by the notch as described above, so that the bearing ball contacts the rotating member and the base through the notch of the recess, and the rotating member passes through the bearing ball. It can be held rotatably with respect to the base. In order to effectively suppress the falling of the bearing ball, it is preferable that at least the width of the notch on the upper surface of the bearing ball holder is smaller than the diameter of the bearing ball, and the width of the notch on the upper and lower surfaces of the bearing ball holder is It is particularly preferable that the diameter is smaller than the diameter of the bearing ball. For example, in the bearing ball holder 1 shown in FIGS. 5 and 6, the width of the notch on the upper surface and the lower surface of the bearing ball holder is set smaller than the diameter of the bearing ball, and the bearing inserted into the recess 1a as shown in FIG. The ball 2 is held by the bearing ball holder 1, and the bearing ball 2 is in contact with the rotating member (substrate holder rotating plate 6) and the base (susceptor 9) through the notch 1c of the recess 1a. The width of the notch on the upper and lower surfaces of the bearing ball holder is preferably smaller by 0.5 to 3 mm than the diameter of the bearing ball, but is not limited to such a width.

  The side surface of the recess provided in the bearing ball holder used in the present invention is preferably set to a shape corresponding to the shape and size of the bearing ball to be held, but is not limited to such a shape. Absent. For example, the side surface of the recess 1a provided in the bearing ball holder 1 of FIG. 5 is set to a curved shape corresponding to the shape and size of the bearing ball to be held. The thickness of the bearing ball holder used in the present invention is set to be smaller than the diameter of the bearing ball. With such a setting, each bearing ball comes into contact with the rotating member and the base through the notch of each recess, and the bearing ball is interposed between the bearing balls. Thus, the rotating member is rotatably held with respect to the base. The thickness of the bearing ball holder used in the present invention is preferably 30 to 90% of the diameter of the bearing ball to be held, but is not limited to such a thickness.

The length of the protrusion of the recess provided in the bearing ball holder used in the present invention is preferably set smaller than the diameter of the bearing ball, but is not limited to such setting. The length of such a protrusion is preferably 50 to 90% of the diameter of the bearing ball, but is not limited to such a length.
In the present invention, the bearing ball holder holding a plurality of bearing balls is preferably installed such that the outer periphery of the bearing ball holder is in contact with the side wall of the bearing groove. With such a configuration, it is possible to effectively prevent the bearing ball holder and the bearing ball held thereon from falling off. For example, in FIG. 2, the bearing ball holder 1 holding a plurality of bearing balls 2 is installed such that the outer periphery of the bearing ball holder 1 is in contact with the side walls of the bearing grooves (6c, 9ba).

The bearing ball holder used in the present invention is preferably made of a material selected from carbon, boron nitride (BN), molybdenum disulfide (MoS ₂ ), tungsten disulfide (WS ₂ ), and combinations thereof. It is not limited to such a material. Since these materials are excellent in lubricity, corrosion resistance and heat resistance, the friction between the bearing ball holder and the bearing ball can be reduced to further prevent the bearing ball from falling off the bearing ball holder. It is also durable for use in environments such as inside growth equipment. In addition, since BN is particularly excellent in corrosion resistance and heat resistance, the bearing ball holder used in the present invention is particularly preferably made of BN.

The bearing ball used in the present invention is preferably a material selected from carbon, BN, MoS ₂ , WS ₂ and combinations thereof, but is not limited to these materials, and the bearing ball holder By selecting the material having excellent lubricity as described above, the material is selected from carbon, BN, MoS ₂ , WS ₂ , alumina, silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), and combinations thereof. A material is also preferable. Since alumina is particularly excellent in strength, corrosion resistance and heat resistance, and BN is particularly excellent in lubricity, corrosion resistance and heat resistance, the bearing ball used in the present invention may be alumina or BN. Particularly preferred.

  Next, the vapor phase growth apparatus shown in FIGS. 1-4 includes the bearing ball holder 1, bearing ball 2, substrate holder 3, substrate holder rotating plate 6, susceptor 9, and susceptor holding plate 18 as well as the susceptor facing surface. 10. A soaking plate 4 mounted on the substrate holder 3 for heating the substrate 5, a heater 11 for heating the soaking plate 4, a reaction furnace 12 comprising a gap between the susceptor 9 and the facing surface 10 of the susceptor, and a raw material gas to the reaction furnace 12. Are provided, and a reaction gas discharge unit 14 for discharging the reaction gas from the reaction furnace 12 is provided. The substrate 5 rotates by rotation of the substrate holder 3, and the substrate 5 rotates by rotation of the susceptor 9. To do.

  First, the rotational driving force from the substrate holder rotational drive unit 8 is transmitted to the substrate holder rotational driving shaft 7 that is rotatably sealed so as not to impair the sealing performance of the reaction vessel 19 by means such as a magnetic fluid seal. A plurality of claws 7 a are provided at the tip of the substrate holder rotation drive shaft 7 on the substrate holder rotation plate 6 side, and the claws 7 a are inserted into holes 6 a provided on the upper surface of the substrate holder rotation plate 6. The rotational drive force is transmitted to the substrate holder rotating plate 6 by being detachably engaged. A plurality of substrate holders 3 are provided around the source gas introducing portion 13, and the gears 6 b provided on the outer periphery of the substrate holder rotating plate 6 and the gears 3 a of the respective substrate holders 3 are engaged with each other. Rotational driving force is transmitted to each substrate 5 and each substrate 5 rotates to obtain a crystal film having a uniform film quality and film thickness within each substrate surface.

  In addition, the rotational driving force from the susceptor rotation driver 15 is first supplied via the susceptor rotation drive shaft 16 that is rotatably sealed by means such as a magnetic fluid seal so as not to impair the sealing performance of the reaction vessel 19. The rotation is transmitted to a susceptor rotating plate 17 fixed to the susceptor side tip of the rotation drive shaft 16. A gear 9aa is provided on the peripheral portion of the susceptor 9 (the outer periphery of the ring-shaped member 9a), and a gear 17a is provided on the peripheral portion of the susceptor rotating plate 17, and the susceptor rotation driver 15 is engaged with each other. Is transmitted to the susceptor 9, and the susceptor 9 rotates. By rotating the susceptor 9 in this way, the substrate 5 revolves, and a crystal film having a uniform film quality and thickness can be obtained between the substrate surfaces.

  The vertical cross section of each bearing groove (6c, 9ab, 9ab ', 9ba, 18a) is preferably semicircular, triangular or quadrangular, but is not limited to such cross section. Each gear (3a, 6b, 9aa, 17a) preferably has a spur gear structure, but is not limited to a spur gear structure. Each bearing groove accommodates at least a part of each bearing ball 2. When using the bearing ball holder, it is preferable that at least a part of the bearing ball holder is also housed in the bearing groove, but it is not limited to being housed.

  The vapor phase growth reaction for generating the crystal film is performed in the reaction furnace 12 inside the reaction vessel 19. A source gas introduction unit 13 is provided at the center of the reaction furnace 12, and the source gas is blown out radially from the source gas introduction unit 13 and supplied horizontally to the crystal growth surface of the substrate 5. It is not limited to. The vapor phase growth reaction is performed by supplying the source gas from the source gas introduction unit 13 while heating the substrate 5 via the soaking plate 4 by the heater 11 in the reaction furnace 12. A crystal film is formed on the substrate. The raw material gas used for the vapor phase growth reaction is directly discharged from the reaction gas discharge unit 14 as a reaction gas. The present invention is not limited to the vapor phase growth apparatus that supplies the source gas from the central part of the reactor and discharges it from the peripheral part to the outside. For example, the source gas is supplied from one end of the reactor and the reaction is performed. It can also be applied to a vapor phase growth apparatus that discharges the later gas to the outside from the other end.

  During vapor phase growth, the substrate 5 is preferably always rotated by the rotation of the substrate holder 3, and more preferably is always rotated and revolved by the rotation of the substrate holder 3 and the susceptor 9. The rotation direction and rotation speed of the substrate holder 3 and the susceptor 9 can be arbitrarily set by changing the rotation direction and rotation speed of the substrate holder rotation driver 8 and the susceptor rotation driver 15, respectively. In order to obtain a uniform film thickness and film quality between the substrates, the substrate holders 3 are arranged on the same circumference with the source gas introduction part 13 as the center, and the distance from the source gas introduction part 13 is made equal. However, it is not limited to such a configuration.

  The preferred materials used for the bearing ball holder 1 and the bearing ball 2 are as described above. Although the material which comprises the reaction container 19 includes a metal or an alloy, it is not limited to these materials. The substrate holder 3, the substrate holder rotating plate 6, the susceptor 9 (ring-shaped member 9 a, disk-shaped member 9 b), the susceptor facing 10 and the susceptor rotating plate 17 are carbon materials or carbon materials coated with ceramic materials. However, it is not limited to such a material. The heater 11 is preferably a carbon heater or a ceramic heater, but is not limited to these heaters. The substrate holder rotation drive shaft 7 and the susceptor rotation drive shaft 16 are preferably a metal, an alloy, a metal oxide, a carbon material, a ceramic material, a carbon material coated with a ceramic material, or a combination thereof. It is not limited to such a material.

Here, examples of the metal include aluminum and the like, but are not limited to aluminum. Examples of the alloy include stainless steel and Inconel, but are not limited thereto. Examples of the carbon-based material include carbon, pyrolytic graphite (PG), and glassy carbon (GC), but are not limited thereto. Examples of ceramic materials include, but are not limited to, alumina, SiC, Si ₃ N ₄ , BN, and the like.

  The material constituting the reaction vessel 19 is particularly preferably stainless steel. Substrate holder 3, substrate holder rotating plate 6, susceptor 9 (ring-shaped member 9a, disk-shaped member 9b), susceptor facing 10 and susceptor rotating plate 17 are SiC coated carbon, heater 11 is a carbon heater, and susceptor rotating drive shaft 16 Is particularly preferably stainless steel. The substrate holder rotation drive shaft 7 is made of Inconel on the side of the substrate holder rotation drive to ensure strength, and the substrate holder rotation plate is used to prevent breakage when engaging with the substrate holder rotation plate 6. It is preferable that the side portion is made of SiC-coated carbon and is integrated by fixing both with screws or the like. The claw 7a is made of SiC-coated carbon and is an end surface of the substrate holder rotating plate side portion of the substrate holder rotating drive shaft 7. It is preferable that they are integrally formed in advance.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited by these.

[Example 1]
(Production of bearing ball holder)
A ring-shaped bearing ball holder 1 (made of BN, inner diameter 202 mm (including protrusions), outer diameter 221 mm, thickness 3 mm) shown in FIG. 5 was manufactured. Each recess 1a was formed by adjacent protrusions 1d (length 3.5 mm) provided only on the inner peripheral side of the bearing ball holder 1. Each recess 1a has a circular insertion port with a diameter of 4.4 mm on the inner peripheral side of the bearing ball holder, has a depth of 3.5 mm in the horizontal direction, and has a notch with a width of 3.2 mm as a bearing ball. It was on the upper and lower surfaces of the holder. The side surface of each recess 1a has a curved shape corresponding to the shape and size of a bearing ball 2 described later. 75 such concave portions were provided at equal intervals in the circumferential direction of the bearing ball holder 1.

(Production of vapor phase growth equipment)
Next, the vapor phase growth apparatus shown in FIGS. First, one bearing ball 2 (made of alumina, spherical with a diameter of 4 mm) is stored in each recess 1a of the bearing ball holder 1 as described above, and a plurality of bearing balls 2 held by the bearing ball holder 1 are used. The substrate holder rotating plate 6 (SiC coated carbon, diameter 255 mm (including gear 6b), thickness 8.5 mm) is a disk-shaped member 9b (SiC coated carbon, diameter 240 mm (including protrusions), thickness 5 mm). Further, the disk-shaped member 9b holding the substrate holder rotating plate 6 is formed into a ring-shaped member 9a (made of SiC coated carbon, outer diameter 720 mm (including the gear 9a), inner diameter 210 mm (including the projecting portion), and thickness 11 mm. The susceptor 9 was formed by holding the substrate holder 6). A similar bearing ball holder in which the number and dimensions of the bearing balls and recesses were appropriately changed was manufactured, and each substrate holder 3 and the susceptor 9 were rotatably held by using the same size and material bearing balls.

(Vapor phase growth experiment)
Using such a vapor phase growth apparatus, gallium nitride (GaN) was grown on the crystal growth surface of the substrate. First, the substrate 5 (diameter 6 inches, sapphire) was set on the substrate holder 3 one by one, and rotation (10 rpm) and revolution (1 rpm) of the substrate 5 were started. Note that the rotation and revolution of the substrate 5 were continued at these speeds until all the growth was completed and the internal temperature dropped to near room temperature, and the inside of the reaction vessel 19 was maintained at atmospheric pressure.

  Thereafter, the substrate 5 was annealed by raising the temperature of the substrate 5 to 1050 ° C. while flowing hydrogen from the source gas introduction part 13. Subsequently, the temperature of the heater 11 is lowered to 510 ° C., and a buffer layer having a thickness of 20 nm made of GaN is grown on the sapphire substrate 5 using trimethylgallium (TMG) and ammonia as source gases and hydrogen as a carrier gas. After the buffer layer growth, the supply of only TMG was stopped, and the temperature of the heater 11 was raised to 1050 ° C. Thereafter, hydrogen and nitrogen were supplied as carrier gases in addition to TMG and ammonia from the source gas introduction unit 13 to grow undoped GaN for 1 hour.

  After growing GaN as described above, the temperature of the heater 11 was lowered to cool the interior to near room temperature, and then the self-revolution of the substrate 5 was stopped. From the start to the end of the self-revolution of the substrate 5, the substrate holder rotation driver 8 and the susceptor rotation driver 15 operated normally. After that, when the reaction vessel 19 was opened and the substrate 5 was taken out, formation of GaN was confirmed on the substrate 5. Further, when each part in the reaction vessel 19 was visually inspected, there was no abnormality such as corrosion, breakage, etc., and no dropout of the bearing ball 2 was confirmed, and all the bearing balls 2 were held by the bearing ball holder. It was in a state.

[Comparative Example 1]
(Production of vapor phase growth equipment)
As shown in FIG. 7, 100 bearing balls 2 are directly sandwiched between a bearing groove 6c provided on the lower surface of the substrate holder rotating plate 6 and a bearing groove 9ba provided on the upper surface of the susceptor 9 (disk-like member 9b). A vapor phase growth apparatus was manufactured in the same manner as in Example except that the substrate holder rotating plate 6 was rotatably held without using the bearing ball holder 1.

(Vapor phase growth experiment)
Using such a vapor phase growth apparatus, a vapor phase growth experiment was conducted in the same manner as in Example 1. However, during the growth of undoped GaN, the gas phase growth experiment was stopped because the alarm device of the substrate holder rotation driver 8 detected an abnormality. After the temperature of the heater 11 was lowered and the inside was cooled to near room temperature, the reaction vessel 19 was opened, and each part in the reaction vessel 19 was visually inspected. One of the 100 bearing balls 2 used to hold the holder rotating plate 6 rotatably is dropped off and is sandwiched between the engagement (3a, 6b) of the substrate holder rotating plate 6 and the substrate holder 3. It was.

  The vapor phase growth apparatus of the present invention is suitable, for example, as a group III nitride semiconductor vapor phase growth apparatus used for manufacturing blue or ultraviolet light emitting diodes or laser diodes.

It is a vertical cross-section block diagram which shows an example of the vapor phase growth apparatus of this invention. It is the A section enlarged view of FIG. It is a BB cross-section block diagram of FIG. It is CC cross-section block diagram of FIG. It is a perspective view from the upper side which shows the bearing ball holder which can hold | maintain the several bearing ball used in order to hold | maintain a substrate holder rotating plate rotatably in the vapor phase growth apparatus of FIG. It is the D section enlarged view of FIG. It is the A section enlarged view of FIG. 1 in the vapor phase growth apparatus of the comparative example 1.

DESCRIPTION OF SYMBOLS 1 Bearing ball holder 1a Recess 1b Insertion slot 1c Notch 1d Protrusion 2 Bearing ball 3 Substrate holder 3a Gear 3b Bearing groove 4 Heat equalizing plate 5 Substrate 6 Substrate holder rotating plate 6a Hole 6b Gear 6c Bearing groove 7 Substrate holder rotation drive shaft 7a Claw 8 Substrate holder rotation drive 9 Susceptor 9a Ring-shaped member 9aa Gear 9ab, 9ab 'Bearing groove 9b Disk-shaped member 9ba Bearing groove 10 Confronting susceptor 11 Heater 12 Reactor 13 Raw material gas introduction part 14 Reactive gas discharge part 15 Susceptor rotation Driver 16 Susceptor rotation drive shaft 17 Susceptor rotation plate 17a Gear 18 Susceptor holding plate 18a Bearing groove 19 Reaction vessel 20 Bellows

Claims (5)

  A vapor phase growth apparatus having a substrate rotation mechanism provided with a rotating member that is rotatably held with respect to a base via a plurality of bearing balls held by a ring-shaped bearing ball holder, A vapor-phase growth apparatus characterized in that the bearing ball-shaped holder has a plurality of recesses for housing the bearing balls on the inner peripheral side.   2. The vapor phase growth apparatus according to claim 1, wherein the length of the protrusion of the concave portion provided in the bearing ball holder is set smaller than the diameter of the bearing ball.   The rotating member is a substrate holder rotating plate provided at the center of the reaction furnace and having a gear on the outer periphery, and is provided around the substrate holder rotating plate from the substrate holder rotating driver via the substrate holder rotating plate. 2. The vapor phase growth apparatus according to claim 1, further comprising: a rotation driving force transmitted to a plurality of substrate holders having gears on an outer periphery to rotate the substrate holder.   The vapor phase growth apparatus according to any one of claims 1 to 3, wherein the bearing ball holder is made of a material selected from carbon, boron nitride, molybdenum disulfide, tungsten disulfide, and combinations thereof.   The vapor phase growth apparatus according to claim 4, wherein the bearing ball holder is made of boron nitride.

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