JPH1112085A - Growth apparatus for chemical vapor deposition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a growth apparatus for chemical vapor deposition, capable of realizing optimized gas composition and growth conditions for obtaining good-quality crystal in epitaxial growth of a GaNbased compound semiconductor. SOLUTION: In the growth apparatus, plural gas passage walls providing flange-like upper plate parts in a cylindrical part and the upper part are arranged at nearly equal intervals so that the center shaft is common to constitute a first gas line to a fourth gas line and gas-constricting part is provided on the concentric circumference to the center axis in the intermediate part of these horizontal flow paths. A susceptor comprising a top board supporting part and a substrate heating part is installed on one circumference of rotating disk plate constituting a part of upper plate part of the gas passage wall and the susceptor is rotatably constituted by rotation driving system 3 of the center shaft. A heater 6 comprising circular quartz tube and lamp house, for heating only susceptor is provided through a circular light passage plate made of quartz and constituting a part of attachable and detachable ceiling plate 5. A discharge gas-constricting part is provided on the circumference which is concentric to the center shaft of intermediate part of the discharge gas passage of the gas discharge part 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical vapor deposition apparatus, and more particularly to a metal organic chemical vapor deposition (MOCVD).
It is suitable for application to an apparatus.

[0002]

2. Description of the Related Art Light-emitting devices such as LEDs and semiconductor lasers and devices such as high-frequency communication transistors manufactured using III-V group compound semiconductors, together with silicon (Si) -based devices, are used in modern information communication society. It is an important element that makes up the hardware infrastructure.

[0003] A III-V compound semiconductor device has a structure that skillfully utilizes a heterojunction of a III-V compound semiconductor, and is used in a region such as a semiconductor laser which cannot be realized by Si. It has a complementary role.

In the manufacture of compound semiconductor devices such as III-V compound semiconductor devices, heteroepitaxy technology is an important technology except for devices having a simple structure such as MESFET. It is no exaggeration to say that this heteroepitaxy technology is supported. The heteroepitaxy technique includes molecular beam epitaxy and chemical vapor deposition, especially MOCVD.
Law is currently the main technology and has been studied academically since the 1960s.

The MOCVD method is an epitaxial growth technique for manufacturing a GaAs semiconductor laser in 1983.
A MOCVD apparatus that has been put into practical use since about 200 years and that performs epitaxial growth on a large number of substrates at once is now on the market. There are various methods in the element technology of the MOCVD apparatus for a large number of substrates. That is, there are a barrel type and a pancake type as a shape of the susceptor, a high flow velocity horizontal type, a high speed rotation type, a vertical type down flow type and the like as a gas flow type, and a substrate mounting method using a gas. There are ones placed above the flow (face-down) and those placed below the gas flow (face-up). The heating methods include a high-frequency heating method, a resistance heating method, and a lamp heating method. Various types of MOCVD apparatuses have been used.

A conventional MOCVD apparatus used for epitaxial growth of a group III-V compound semiconductor uses gallium (Ga), aluminum (Al) or indium (In) as a group III element and arsenic (As) as a group V element. Alternatively, phosphorus (P) was used, and the growth temperature was at most 800 ° C. On the other hand, in recent years, ammonia (NH
₃ ) A GaN-based semiconductor device using raw materials as a raw material has been developed.
The demand for VD devices has increased.

[0007]

SUMMARY OF THE INVENTION MO of GaN-based semiconductor
In a CVD apparatus, an organic group III metal and N 2 are deposited on a substrate made of sapphire or SiC at a temperature of about 1000 ° C.
By reacting with H ₃ , a single crystal thin film is grown. In the growth of this single crystal thin film, the gas composition and growth conditions for growing good quality crystals have already been published and are known academically. However, MOCVD for realizing optimized gas composition and growth conditions for obtaining high-quality crystals
The devices have been modified as a result of individual technological developments and are generally unknown. Among the known MOCVD apparatuses, there are known ones related to a reaction tube structure (for example, JP-A-2-288665, JP-A-2-610).
82, JP-A-4-94719). However, these known techniques are applied to MOCVD for a large number of substrates.
It is difficult to apply to the apparatus as it is.

Accordingly, an object of the present invention is to provide a chemical vapor deposition apparatus capable of realizing optimized gas composition and growth conditions for obtaining high-quality crystals in epitaxial growth of a GaN-based semiconductor. is there.

[0009]

Means for Solving the Problems The present inventor has made intensive studies in order to solve the above-mentioned problems of the prior art. The outline is described below.

According to the knowledge of the present inventor, an MOCVD apparatus for growing a GaN-based semiconductor using NH ₃ as a main raw material is not suitable for growing an As-based or P-based semiconductor in consideration of the chemical characteristics of NH _3. A technical idea different from that of the MOCVD apparatus is required. That is, in a MOCVD apparatus in which a GaN-based semiconductor is grown by using NH ₃ as a main source gas, the decomposition efficiency of NH ₃ is low, and a high-speed reaction between NH ₃ and a group III source in the gas phase. In order to optimize the carrier gas due to the difficulty of supplying the raw material due to thermal convection and the difference in the raw material composition (or the crystal composition) in the high temperature growth of about 1000 ° C., the composition of the carrier gas during the crystal growth is changed (for example, H ₂ / Change of N ₂ composition) and the like, which is different from the MOCVD apparatus for growing an As-based or P-based semiconductor. Considering these facts, no example has been disclosed in which the invention is applied to an MOCVD apparatus for a large number of substrates.

In general, the growth rate of a crystal depends on the gas flow rate near the substrate surface. Therefore, when the substrate on which the crystal is grown is arranged, for example, on the circumference and the source gas is discharged from the center of the circumference, the gas flow flowing out from the center of the circumference spreads radially, and the circumferential length at the upstream of the gas flow is increased. On the other hand, the peripheral length downstream thereof becomes longer, so that the gas flow velocity decreases and the thickness of the crystal-grown film becomes non-uniform. This film thickness non-uniformity can be improved by rotating the substrate. However, even if the crystal is not uniformly grown on the substrate even when the substrate is not rotated, further uniformity when the substrate is rotated cannot be guaranteed. Therefore, if the gas flow velocity around the substrate is made equal in all parts of the substrate, further uniformity of the film thickness of the crystal-grown film when the substrate is rotated can be ensured. That is, in order to uniformly grow compound semiconductors on a large number of substrates at the same time, it is necessary to supply a source gas uniformly on each of the substrates. The same number of substrates must flow at the same flow rate in every part of each substrate. However, in the conventional MOCVD apparatus, the carrier gas cannot always flow at the same flow rate in every part of each substrate. Therefore, in order to allow the carrier gas to flow at the same flow rate in all portions of each of the multiple substrates, the cross-sectional area increases from the upstream side to the downstream side of the gas passage around the susceptor holding the substrate. In order to avoid such a situation, it is preferable that the configuration be made so as to decrease the value.

In order to prevent nonuniformity of gas flow due to thermal convection, a face-down system is ideal. However, in the face-down method, since the method of attaching the substrate to the susceptor is a mechanical fixing method using pins (screw), the gas flow of the reaction gas is disturbed by the projections formed by the pins and the like, and the shadow effect is generated. Has occurred. Then, due to the turbulence of the gas flow and the shadow effect, crystal growth in the peripheral portion of the projection such as a pin becomes abnormal, and the portion has a defective portion such that a semiconductor element cannot be formed. In addition, the board is soiled during the work of mounting and removing the board, and time is wasted on mounting and removing the board. In order to prevent these, it is only necessary not to use pins or the like to fix the substrate to the susceptor.For that purpose, using a susceptor having an opening for exposing a surface for crystal growth, It is effective to place a substrate with the growth surface facing downward in the opening.

As a heating method for heating these substrates, there are roughly three methods. That is,
The high-frequency heating method, the resistance heating method, and the lamp heating method described above. However, in these heating methods,
Since a plurality of substrates are arranged on a large integrated susceptor and the entire large integrated susceptor is heated, all portions between the substrates are also heated, and only the substrate is efficiently heated. Was not possible with any of the heating methods.

For example, in a method of heating a susceptor using a pancake type susceptor, a carbon susceptor for revolving the substrate is intricately combined with a carbon susceptor for revolving the substrate. In order to heat the substrate, the carbon susceptor for revolving the substrate is first heated, and the heat is conducted to the carbon susceptor for rotating the substrate, thereby heating the carbon susceptor for rotating the substrate. As described above, in order to heat the substrate, it is necessary to heat the carbon susceptor for revolving the substrate having a larger area, which not only results in poor thermal energy efficiency, but also reduces the amount of the source gas other than the substrate. This promoted the decomposition and precipitation, and the efficiency of using the raw material gas was deteriorated. Therefore, if a large integrated susceptor is not used, and only the substrate is heated to improve the efficiency of thermal energy, excessive decomposition and deposition of the source gas other than the substrate can be reduced. Can be. For this purpose, a susceptor that supports only one substrate is arranged on one circumference,
It is effective to use a heating device that heats only this part of the circumference.

Further, as conventionally known, Ga
For the growth of InN crystals, it is desirable that the amount of H ₂ gas as a carrier gas is small, whereas for the growth of AlGaN crystals, it is desirable that the amount of H ₂ gas as a carrier gas be large. For this reason, GaIn
When growing a multi-layered film of N / AlGaN, H
The composition switching between the _two gases and the N ₂ gas must be performed instantaneously. However, it is difficult to instantaneously switch a large amount of gas to a gas composition optimal for crystal growth.
Therefore, in order to instantaneously obtain an optimal gas composition for crystal growth, it is sufficient to switch a small amount of gas so that an optimal gas composition for crystal growth can be obtained. For this purpose, it is effective to provide a plurality of gas passages through which the carrier gas flows, and to change the composition of the carrier gas flowing through one of the gas passages so as to obtain an optimum gas composition for crystal growth. is there.

In the gas discharge, MOCVD is used.
The number of gas discharge pipes connected to the apparatus for discharging gas to the outside is limited, and the gas flow velocity near the gas discharge pipe on the growth surface of the substrate (downstream) increases, and the gas flow pipe is located far from the gas discharge pipe. The flow velocity of the (upstream) gas decreases. That is, in the vicinity of the substrate surface, the flow rate of the reaction gas becomes non-uniform on the growth surface of the substrate, so that the crystal growth speed becomes non-uniform and the thickness of the epitaxially grown film becomes non-uniform. In order to prevent this, the gas flow rate may be constant at a portion far from the gas discharge pipe and at a portion near the gas discharge pipe. For this purpose, it is effective to provide a gas constriction in the gas exhaust pipe downstream of the susceptor. The present invention has been devised based on the above study.

That is, in order to achieve the above object, a first invention of the present invention provides a plurality of susceptors arranged on one circumference and a plurality of gases for supplying a reaction gas toward the susceptor. In a chemical vapor deposition apparatus having a passage and a heating means for heating a susceptor, at least one of a plurality of gas passages is provided with a gas constriction on a circumference concentric with the circumference. It is a feature.

In the first invention, preferably, all of the plurality of gas passages are provided with gas constrictions.

Specifically, in the first invention, the plurality of gas passages include a first gas passage for a group III element source gas and a second gas passage for a group V element source gas. , The first gas passage and the second gas passage are configured to merge at an angle of 10 to 90 ° downstream of the gas constriction portion, and the merge point is where the gas flowing through the gas passage is formed. Get as close to the susceptor as possible to mix well. When the supplied gas contains NH ₃ , the distance from the susceptor to the confluence point is 2 to 2 to suppress the addition reaction.
It is selected to be 15 cm, preferably 10 cm or less.

In the first invention, the plurality of gas passages are, specifically, a first gas passage for a group III element source gas and a second gas passage for a group V element source gas. ,
A third gas passage for a carrier gas of an inert gas and a fourth gas passage for a carrier gas of an inert gas containing hydrogen, wherein the third gas passage and the fourth gas passage are formed of a susceptor. At the periphery, the first gas passage and the second gas passage merge so as to be substantially parallel to the merged gas passage.

In the first aspect of the present invention, preferably, the cross-sectional area of the gas passage after the merging of the plurality of gas passages around the susceptor decreases from the upstream side to the downstream side of the gas passage. Specifically, by inclining the surface of the gas passage wall facing the susceptor with respect to the susceptor among the gas passage walls constituting the gas passage after the merge, the gas passage after the merge is formed. Is configured such that the cross-sectional area decreases from the upstream side to the downstream side.

According to a second aspect of the present invention, there are provided a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating for heating the susceptor. Means, wherein an annular rotating plate provided with a plurality of openings for installing a susceptor constitutes a part of a passage wall of one gas passage of the plurality of gas passages. It is a feature.

In the second invention, typically, when a plurality of susceptors are installed at a plurality of openings of the rotating plate, the lower surface of the susceptor forms a part of a passage wall of a gas passage. The lower surface of the rotating plate and the lower surface of the susceptor constitute the same surface.

In the second aspect of the invention, specifically, the susceptor is configured to be able to revolve by rotation of a heat insulating rotary plate holding the susceptor. In the second invention, for example, the susceptor has a first gear on an outer peripheral portion, and the first gear is connected to a second gear fixed to the chemical vapor deposition apparatus. The susceptor is configured to be able to rotate when the first gear is rotated by the rotation of the rotating plate. The second gear is formed of a ring provided with a gear on the inner peripheral portion, a circular plate provided with a gear on the outer peripheral portion, or the like.

In the second aspect, in order to maintain a smooth gas flow, the lower surface of the rotating plate and the lower surface of the susceptor are substantially on the same plane.

According to a third aspect of the present invention, there are provided a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating for heating the susceptor. Means, wherein the susceptor comprises a substrate holding unit having an opening for installing the substrate, and a substrate heating unit for transmitting heat to the substrate to heat it. is there.

In the third aspect of the invention, typically, the substrate holding portion has a projection at a lower portion for holding the substrate. Further, in the third invention, specifically, the substrate heating section is fixed in contact with a substrate installed on the substrate holding section by its own weight, and is provided detachably with respect to the substrate holding section. Can be

According to a fourth aspect of the present invention, there are provided a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas to the susceptor, and a heating for heating the susceptor. Wherein the heating means comprises an annular light source and an annular reflecting mirror for condensing the light emitted by the light source on the susceptor. It is.

In the fourth aspect of the invention, in order to heat the susceptor efficiently, the cross-sectional shape in the radial direction of the annular reflecting mirror is preferably an elliptical shape in which the annular light source is located at one focal point. It has a parabolic shape with an annular light source located at the focal point. In the fourth invention, the heating means and the reaction system in which the susceptor is placed are separated by a light passing plate made of, for example, quartz, and the inside of the heating means and the portion between the susceptor and the light passing plate are separated. Is filled with an inert gas. In addition, the fourth invention typically further includes anti-fog means for blowing anti-fog on the surface of the light passing plate on the side where the susceptor is present, for example, by blowing an inert gas.

In the fourth aspect of the present invention, specifically, there is provided an annular rotating plate provided with a plurality of openings for holding a plurality of susceptors, and the inner peripheral surface of the rotating plate has a light reflecting surface. Two cylinders having different radii constituting the surface are provided concentrically with the rotating plate so as to sandwich a plurality of openings, and a surface of the two cylinders where the openings exist is, for example, a gold (Au) film or the like. Is provided.

According to a fifth aspect of the present invention, there are provided a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating for heating the susceptor. Means and a gas exhaust means for exhausting a reaction gas, wherein the gas exhaust means has an exhaust gas constricted portion.

In the fifth aspect of the invention, typically, the gas exhaust means is connected to an exhaust gas pipe for exhausting the reaction gas to the outside of the chemical vapor deposition apparatus, downstream of the exhaust gas constriction. It further has an exhaust gas reservoir.

In the fifth aspect of the present invention, the exhaust gas confinement portion is composed of, for example, a thin plate having a plurality of minute openings and a groove.

According to a sixth aspect of the present invention, there are provided a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating for heating the susceptor. Means for attaching and detaching a top plate for separating a reaction system in which a susceptor is placed and a heating means, and top plate supporting means for supporting the top plate. Things.

In the sixth aspect, the top plate is preferably formed by combining a portion made of quartz and a portion made of a metal such as stainless steel.

In the sixth aspect, the top plate supporting means is, specifically, a central axis of the rotating means for rotating the rotating plate holding the susceptor.

In the present invention, typically, the reaction gas flowing through the gas passage is configured to flow parallel to the surface of the substrate provided on the susceptor.

According to the first aspect of the present invention configured as described above, a plurality of susceptors are arranged on one circumference, and a gas passage for supplying a reaction gas to the plurality of susceptors is provided. By providing the gas constriction on the circumference concentric with the circumference on which the susceptor is arranged, the pressure loss in the gas passage of the reaction gas can be made smaller than the pressure loss in the gas constriction. The pressure on the upstream side can be higher than the pressure on the downstream side, so that the pressure of the reaction gas can be made uniform over the circumferential direction of the gas constriction.

According to the second aspect of the present invention, since the annular rotating plate forms the passage wall of the gas passage, when the reaction gas flows through the gas passage, the reaction gas reaches the susceptor. Can be defined.

According to the third aspect of the present invention, the susceptor has a substrate holding portion having an opening for holding the substrate;
The substrate for crystal growth can be easily fixed to the susceptor without using pins or the like, because the substrate heating unit is configured to transmit heat to the substrate to heat the substrate.

According to the fourth aspect of the present invention, the heating means comprises an annular light source and an annular reflecting mirror for condensing light emitted from the light source on the susceptor. , Only the susceptor can be heated.

According to the fifth aspect of the present invention, since the gas exhaust means for exhausting the reaction gas has the exhaust gas constriction, the pressure of the reaction gas is reduced in the circumferential direction of the exhaust gas constriction. Over the entire surface.

According to the sixth aspect of the present invention, a detachable and detachable top plate for separating the heating system from the reaction system in which the susceptor is placed, and a top plate support for supporting the top plate With this configuration, the pressure applied to the top plate can be applied to the top plate support portion.

[0044]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In all the drawings of the following embodiments, the same or corresponding portions are denoted by the same reference numerals.

FIG. 1 shows a horizontal MOCV according to this embodiment.
1 shows the overall configuration of a D device.

As shown in FIG. 1, a horizontal MOCVD apparatus according to this embodiment includes a gas line / gas supply system 1, a gas discharge unit 2, a rotary drive system 3, a susceptor / rotary annular plate 4,
It has a top plate 5 and a heating device 6. The gas line / gas supply system 1 is for supplying a source gas such as a group III element or a group V element and a carrier gas such as an inert gas to the reaction unit. The gas discharge unit 2 is for discharging the exhaust gas after the reaction to the outside. Rotary drive system 3
Is for rotating the susceptor / rotating annular plate 4. The top plate 5 is for separating the reaction unit on which the susceptor / rotating ring plate 4 is placed from the heating device 6, and the portion of the top plate 5 directly below the heating device 6 passes light for heating. You can do it.

FIG. 2 shows a radial cross section of the gas line / gas supply system 1. The gas line / gas supply system 1 is for supplying a source gas used for crystal growth and a dummy gas (carrier gas) that does not directly contribute to crystal growth to the substrate 8 mounted on the susceptor 7. This gas line /
In the gas supply system 1, a plurality of gas passage walls 9 to 13 composed of a cylindrical portion and a flange-shaped flat plate portion on the upper portion thereof are arranged at a substantially constant interval from each other with a common central axis OO. It is configured. The gas passage wall 9 and the gas passage wall 10
A space portion between the first gas line and the second gas line constitutes a first gas line 14 for flowing a source gas of, for example, a group III element. Further, a space between the gas passage wall 10 and the gas passage wall 11 is provided with a second gas line 15 for flowing, for example, a group V element source gas.
Is configured. The space between the gas passage wall 11 and the gas passage wall 12 constitutes a third gas line 16 for flowing, for example, a mixed gas of N ₂ gas and H ₂ gas. Also,
The space between the gas passage wall 12 and the gas passage wall 13 constitutes a fourth gas line 17 for flowing an inert gas such as N ₂ gas. Dummy gases such as group III element and group V element source gases and N ₂ gas are introduced from gas inflow terminals (not shown) such as VCR joints attached to the side surfaces of the cylindrical portions of the gas passage walls 10 to 13. It is configured as follows.

The first gas line 14, the second gas line 15, the third gas line 16 and the fourth gas line 17 have their respective gas passage walls 10
Upper plates 13 to 13 form a horizontal flow path having a vertically stacked structure, and when gas is introduced into these horizontal flow paths, the gas flows radially inside the horizontal flow path. Gas constrictions 10a to 13a are provided on the upper plates of the gas passage walls 10 to 13 at the intermediate portions of the horizontal flow paths, respectively, on the circumference concentric with the central axis OO. Here, the gas constricted portions 10a to 13a are provided separately from each other along the circumferential direction. FIG. 3 shows a cross section along the circumferential direction of the gas constricted portion 10a.
The same applies to the gas constricted portions 11a to 13a. Then, the gas flows into these gas constricted portions 10a to 13a.
When passing through the gas constriction portions 10a to 13a, the pressure of the gas on the downstream side is 1
It is configured to be lower by about 0 Torr.

The gas constriction portion 10a is provided at an intermediate portion of the upper plate portion of each of the first gas line 14 to the fourth gas line 17.
To 13a, the first
When the gas flows through the gas line 14, the second gas line 15, the third gas line 16, and the fourth gas line 17, the gas pressure loss in the horizontal flow path portion is reduced by the gas constricted portions 10a to 13a. Is smaller than the gas pressure loss in the gas confining portions 10a to 13
A can be made uniform over the circumference of a, and the gas can flow radially and uniformly.

Further, the first gas line 14 and the second gas line 15 are configured to merge at an angle on the upstream side around the susceptor 7. Here, the upper and lower widths of the gas lines at the merging portion are larger than the sum of the upper and lower widths of the first gas line 14 and the second gas line 15 at the non-merging portion. It is configured to be smaller. That is, the raw material gas of the group III element flowing through the first gas line 14 and the second gas line 15
The raw material gas of the group V element flowing into the susceptor 7 joins before being supplied to the susceptor 7, that is, on the upstream side, and the cross-sectional area of the flow of those gases decreases toward the downstream side. Here, even if these source gases that flow radially and uniformly are combined, the uniformity of the flow of the source gases is maintained.

As described above, the first gas line 14 and the second
Make an angle with each other, and the upper and lower widths of the gas lines after the merging of the group III element source gas and the group V element source gas are equal to the upper and lower widths of the respective gas lines before the merging of the source gases. Is smaller than the sum of the widths, the source gas of the group III element and the source gas of the group V element can be sufficiently mixed on the upstream side of the susceptor 7.

The optimum angle between the first gas line 14 and the second gas line 15 depends on the distance from the point where they merge to the susceptor 7. That is, for example, the first gas line 14 and the second gas line 1
If the distance from the point where the convergence point 5 merges to the susceptor 7 is short, the angle must be increased in order to quickly mix the group III element and group V element source gases flowing into them, and if the distance is long, the angle must be increased. Must be reduced. For this reason, the angle θ between the first gas line 14 and the second gas line 15 is selected from 10 ° to 90 °, and in this embodiment, the angle θ is selected, for example, to 30 °.

[0053] When the raw material gas of Group V element comprises NH _3, the NH ₃ is trimethyl gallium (TMG)
In order to prevent the formation of a solid such as (NH ₃ ) ₂ Ga (CH ₃ ) ₂ which lowers the crystal growth efficiency by causing an addition reaction with trimethylaluminum (TMA) or the like, The distance from the point where the source gas and the source gas of the group V element merge to the susceptor 7 is selected to be 2 to 15 cm, preferably 2 to 10 cm, and in this embodiment, for example, 4 cm.

The third gas line 16 and the fourth gas line 17 through which the dummy gas flows are configured to join, for example, below the susceptor 7 on the outer peripheral portion of the horizontal flow path. The surface facing the susceptor 7, that is, the surface facing the susceptor 7, is inclined so that the flow path cross-sectional area decreases toward the downstream of the gas line.

Here, the dummy gas is supplied to the third gas line 1
The gas is introduced into the sixth and fourth gas lines 17 for the following reason. That is, the radiant heat of the heated susceptor 7 heats the opposing surface of the susceptor 7, but when growing a group III element and a group V element on the growth surface of the substrate 8 placed on the susceptor 7, When the raw material gas of the group III element or the group V element comes into contact with the facing surface of the susceptor 7, the raw material of the group III element or the group V element is decomposed and deposited on the facing surface, and the raw material is wastefully used. This is to prevent this. In addition, for example, when measuring the temperature around the susceptor 7, a thermometer is installed on the facing surface, and if the raw material decomposes and precipitates on the facing surface of the susceptor 7, the temperature measurement will be hindered. This is to prevent this. Then, the third gas line 16 and the fourth gas line 1
By flowing a dummy gas such as an inert gas into the nozzle 7 so as to prevent contact between the source gas and the opposing surface of the susceptor 7, a high-concentration source gas can be flowed, and the supply amount of the source increases. Without this, the growth rate of the crystal can be increased.

The reason for flowing the dummy gas is as follows besides preventing the contact between the source gas and the opposing surface of the susceptor 7. That is, in general, the flow velocity of the raw material gas flowing radially below the susceptor 7 decreases as it goes downstream, but the thickness of the concentration boundary layer of the raw material gas flowing radially increases due to the decrease in the flow velocity. This is to prevent the crystal growth rate from decreasing as it goes downstream of the source gas. Specifically, as described above, the facing surface of the susceptor 7 is inclined with respect to the susceptor 7, and the raw material gas is compressed by flowing a dummy gas near the facing surface, so that the flow path cross-sectional area becomes smaller toward the downstream. Then, by increasing the gas flow rate toward the downstream, a decrease in the growth rate is prevented and the substrate 8
The growth rate on the growth surface is made uniform.

The dummy gas is supplied to the third gas line 16.
The reason why the dummy gas flows through the third gas line and the fourth gas line 17 is as follows. That is, the dummy gas flowing through the fourth gas line 17 of the two gas lines flows while being in contact with the facing surface of the susceptor 7, and plays a role of maintaining the flow rate of the entire gas. Therefore, an inert gas such as N ₂ gas is mainly used as the dummy gas flowing through the fourth gas line 17. On the other hand, the dummy gas flowing in the third gas line 16 flows substantially in parallel while contacting the source gas, and a part of the dummy gas may be mixed with the source gas. That is, the composition of the dummy gas flowing in the third gas line 16 is, for example, a composition mainly composed of H ₂ when growing an AlGaN layer on the growth surface of the substrate 8, and N when growing a GaInN layer. _The composition is mainly composed of ₂ . As described above, the composition of the dummy gas flowing through the third gas line 16 is optimized by the compound semiconductor grown on the growth surface of the substrate 8. Then, the dummy gas is caused to flow through the two gas lines, and only the composition of the dummy gas flowing through one of the gas lines is changed by the compound semiconductor to be grown. A suitable dummy gas can be supplied. for that reason,
It is not necessary to replace all the dummy gases every time a different crystal is grown, the fluctuation of the supply pressure of the primary pipe due to the replacement of the dummy gas can be reduced, and the burden on the flow rate control of each gas line is greatly reduced. be able to.

The rotary drive system 3 and the susceptor / rotating annular plate 4 are used to revolve and rotate the susceptor 7 and, in this embodiment, are configured as shown in FIG. FIG. 5 is a sectional view and a plan view showing the susceptor 7 according to this embodiment.

As shown in FIG. 4, the rotary drive system 3 and the susceptor / rotating annular plate 4 are made of a material having a heat insulating property that does not absorb visible light and near infrared rays, for example, an annular rotating annular plate made of quartz. 20 is configured to be rotatable about a central axis OO. A plurality of circular openings 20a for mounting a plurality of susceptors 7 are provided on the concentric circumference of the rotary annular plate 20.
Are removably mounted on these openings 20a and rotatably mounted on these openings 20a. By holding the susceptor 7 in these openings 20a, the lower surfaces of the susceptor 7 and the rotary annular plate 20 form a smooth surface of the gas passage wall 9 and allow a gas such as a source gas or a dummy gas to flow. In doing so, it plays a role in regulating the gas flow. Here, as an example of the dimensions of the rotary ring plate 20, the thickness of the rotary ring plate 20 is 6 mm and the radius is 260 mm. In addition, diameter 63mm
The circular opening 20a is formed so that its center is superimposed on a circumference having a radius of 190 mm centered on the central axis OO of the rotating annular plate 20.

As shown in FIG. 5A, the susceptor 7 includes a substrate holding section 7a and a substrate heating section 7b, each of which is made of, for example, SiC. As shown in FIG. 5B, the substrate holding portion 7a has a shape of the substrate 8 and a substrate heating portion 7b.
Has an annular shape provided with an opening 7c corresponding to the shape of. Hooks 7d to 7f protruding from the opening 7c are provided at, for example, three portions below the substrate holding portion 7a. Each of the hooks 7d to 7f has a thickness of, for example, 0.5 mm in the radial direction of the substrate holding portion 7a.
5 mm, width 2 mm, length 1 mm. The substrate 8 and the substrate heating unit 7b are held at the position of the opening 7c by the hooks 7d to 7f. That is, when holding the substrate 8 on the susceptor 7, the substrate 8 with the growth surface directed downward from above the substrate holding portion 7a is dropped into the opening 7c, and is held by the hooks 7d to 7f. Is placed on the substrate 8.
The substrate heating section 7b is pressed against the substrate 8 by its own weight. Therefore, by heating the substrate heating unit 7b, heat is conducted from the substrate heating unit 7b to the substrate 8,
The substrate 8 can be heated. When the substrate 8 is taken out from the susceptor 7, the substrate heating unit 7b is sucked up and taken out using, for example, vacuum tweezers, and then the substrate 8 is sucked up and taken out.

Further, as shown in FIG.
Is fixed to a horizontal MOCVD device on the outside and a gear 2
An annular rotation ring 21 having 1a is provided, and the susceptor 7 is configured to be able to rotate by meshing with a gear 7g provided on the outer periphery of the susceptor 7.
The susceptor 7 revolves around the central axis OO of the rotary annular plate 20 while the susceptor 7 itself rotates by rotating the rotary annular plate 20 around its central axis OO by the rotary drive system 3. Revolves around the central axis.

As described above, by mounting the substrate 8 on the susceptor 7 with the growth surface facing downward,
Since, for example, screws or pins are not used to hold the substrate 8 on the susceptor 7, gas turbulence and shadow effects due to projections such as screws and pins can be prevented, and the susceptor 7 Since attachment and removal of the substrate 8 can be simplified, contamination of the substrate 8 can be prevented.

Next, as shown in FIG. 7, the heating device 6
An annular quartz tube lamp 30 serving as a light source and an annular lamp house 31 for condensing infrared rays emitted from the quartz tube lamp 30 on the susceptor 7 have a common central axis. Here, the annular lamp house 3
The shape of the cross section in the radial direction 1 is, for example, a parabolic shape, and the annular quartz tube lamp 30 is provided at the focal point of the parabola. Also, this lamp house 31
Has an inner peripheral surface serving as a light reflecting surface, and reflects an infrared ray emitted from the quartz tube lamp 30 on the light reflecting surface to form a central axis OO.
And the light is focused on the susceptor 7. Here, the susceptor 7 is connected to the opening 2 of the rotary annular plate 20 through the light passing plate 5a through which light passes below the heating device 6.
0a. The reaction system in which the heating device 6 and the susceptor 7 below the heating device 6 are placed includes a light passing plate 5a.
Are spatially separated and separated by Light passing plate 5
a is an annular quartz plate having a width slightly larger than the diameter of the susceptor 7 corresponding to the shape of the heating device 6,
It constitutes a part of the top plate 5 in the CVD apparatus. Two cylinders 32 and 33 made of, for example, molybdenum (Mo) having different radii are overlapped on the rotating annular plate 20 in the radial direction while overlapping their central axes with the central axis OO of the rotating annular plate 20. It is provided so as to sandwich the susceptor 7. Light reflecting films 32a and 33a made of, for example, an Au film for reflecting infrared rays from the heating device 6 toward the susceptor 7 are provided on the surfaces of the two cylinders 32 and 33 on the susceptor 7 side.
Is provided. Thereby, the two cylinders 32, 3
3 is reflected toward the susceptor 7, so that most of the infrared light emitted from the quartz tube lamp 30 is effectively irradiated on the susceptor 7, and
Can improve the uniformity and efficiency of heating.

The space defined by the susceptor 7 and the light passing plate 5a is configured to be filled with an inert gas, and an inert gas for blowing the inert gas onto the lower surface of the light passing plate 5a. Active gas inlet pipe (not shown)
Is provided. This is because the gas flowing below the susceptor 7 during the crystal growth may leak above the susceptor 7 from the gap between the sliding surfaces of the susceptor 7 and the rotating annular plate 20, The leaked gas passes through the light passing plate 5a.
This is to prevent light from being adhered to and fogging and reducing the amount of light transmitted through the light passing plate 5a. That is, the inert gas is blown onto the lower surface of the light passing plate 5a through the inert gas introducing pipe to prevent the light passing plate 5a from fogging and to maintain a constant amount of infrared rays from the heating device 6. .

As shown in FIG. 8, the gas discharge section 2 includes an exhaust gas constriction section 40, an exhaust gas storage section 41, and a plurality of exhaust gas pipes. The exhaust gas constriction portion 40 and the exhaust gas reservoir portion 41 are provided on a portion of the susceptor 7 downstream of the susceptor 7 on a circumference concentric with the rotary annular plate 20. Further, the plurality of exhaust gas pipes 42 are provided outside the exhaust gas reservoir 41 on the rotating annular plate 2.
0 and are arranged at equal intervals on a circle concentric with
1 and is provided. Here, for example, the exhaust gas constriction portion 40 is formed of a mesh-shaped thin plate 40 a made of a metal such as stainless steel and provided with a large number of minute holes and a groove 4.
0b. Here, the diameter of one minute hole provided in the mesh-shaped thin plate 40a is, for example, 0.1 mm.
3 mm, and the surface density is, for example, 1 piece / mm ² . The dimension of the groove 40b is, for example, 5 × 5 mm.

The exhaust gas constricted portion 40 is provided at a portion (downstream) close to the flow velocity of the gas below the susceptor 7 at a portion (upstream) far from the exhaust gas pipe 42 when flowing the gas. This is to prevent the gas flow rate on the growth surface of the substrate 8 from becoming non-uniform due to an increase in the gas flow rate below the susceptor 7. By providing the exhaust gas constriction portion 40 in this manner, the pressure of the exhaust gas can be made uniform over the circumferential direction of the exhaust gas constriction portion 40. Therefore, the gas discharge can be made uniform in all the portions of the substrate 8,
Since the gas flow velocity can be made uniform on the growth surfaces of all the substrates 8, the uniformity of crystal growth can be improved. Further, by providing the exhaust gas reservoir 41 on the circumference, the number of exhaust gas pipes 42 connected to the exhaust gas reservoir 41 can be reduced.

As shown in FIG. 9, the top plate 5 includes a disk 5b made of metal such as stainless steel, an annular light transmitting plate 5a made of quartz, for example, provided on the outer periphery of the disk 5b, An annular metal plate 5c made of, for example, stainless steel provided on the outer periphery of the plate 5a. As described above, the light passing plate 5a is configured in a shape corresponding to the shape of the heating device 6 so as to pass infrared rays emitted from the heating device 6 (not shown) provided above. The top plate 5 is supported by the top plate support 50 at the center of the disk 5b, whereby the vertical position of the top plate 5 is fixed. In addition, since the rotating annular plate 20 and the susceptor 7 are configured to be rotatable by the rotary drive system 3, the top plate support 50 is provided with a bearing so as not to transmit the rotational motion to the top plate 5. (Not shown) is provided.

When removing the substrate 8 from the susceptor 7, first, the quartz tube lamp 30 of the heating device 6 and the top plate 5
And both are raised upward. Next, using vacuum tweezers (not shown), the substrate heating unit 7b is sucked up and taken out, and then the substrate 8 is sucked up and taken out.

As described above, the top plate 5 is composed of the disk 5b or metal plate 5c made of, for example, stainless steel and the light transmission plate 5a made of quartz, and is provided on the center axis of the horizontal MOCVD apparatus. By being supported by the section 50, sufficient mechanical strength can be obtained even when pressure is applied to the top plate 5 due to the reduced pressure of the reaction section in the horizontal MOCVD apparatus.

Next, a method for growing GaN on the growth surface of the substrate 8 in the lateral MOCVD apparatus according to this embodiment configured as described above will be described.

Now, the flat plate 5 and the heating device 6 are connected to a horizontal MOC.
In a state where the susceptor 7 is removed from the VD device, a plurality of substrates 8
Put. In this state, the space between the susceptor 7 and the top plate 5 is filled with an inert gas such as N ₂ gas. Next, after the top plate 5 is covered with the heating device 6, power is transmitted to the rotary drive system 3 by a predetermined method, and the rotary annular plate 20 is rotated at a predetermined rotation speed. Thereby, the plurality of susceptors 7 revolve and rotate around their own central axes. Further, the susceptor 7 is heated by the heating device 6.
Is heated to a predetermined temperature.

Next, as shown in FIG. 2, a mixed gas of, for example, N ₂ gas and H ₂ gas is introduced as a dummy gas (carrier gas) into the third gas line 16 through a gas inflow terminal (not shown). And the fourth gas line 17
After introducing, for example, an inert gas such as N ₂ gas as a dummy gas into the first gas line 14 through the gas inflow terminal in the same manner, for example, TMG (Ga (CH
₃ ) A source gas containing ₃ ) is introduced, and a source gas containing, for example, NH ₃ as an N source is introduced into the second gas line 15. Here, the dummy gas introduced into the third gas line 16 has a composition of the dummy gas that is optimal for the crystal growth of GaN. The source gas and the dummy gas radially and uniformly flow through the horizontal flow paths of the first to fourth gas lines 14 to 17, respectively, and after passing through the gas constrictions 10 a to 13 a, respectively, the upstream side of the susceptor 7. Then, the group III element source gas and the group V element source gas merge at an angle of, for example, 30 °. Next, below the susceptor 7, the first gas line 14 and the second gas line 1
5 and the dummy gas flowing in the third gas line 16 and the fourth gas line 17 merge substantially in parallel. Thus, TMG and NH ₃ are thermally decomposed and reacted below the susceptor 7, and GaN is grown on the growth surface of each substrate 8 provided on each susceptor 7. Then, as shown in FIG. 8, the exhaust gas including the material gas and the dummy gas containing the reaction products and the material not deposited on the growth surface on the substrate 8 passes through the exhaust gas constriction portion 40 and once After being stored in the exhaust gas storage section 41, it is discharged to the outside through an exhaust gas pipe 42.

After the crystal growth of GaN is completed, the introduction of the raw material gas and the dummy gas is stopped while the heating by the heating device 6 is stopped, and then the rotation of the rotary annular plate 20 is stopped. Next, after the top plate 5 and the heating device 6 are both lifted up and removed from the horizontal MOCVD device, the substrate 8 after the completion of the crystal growth is sucked out from the susceptor 7 using a plurality of, for example, vacuum tweezers and taken out.

Although GaN crystals are grown on the substrate 8 in the above description, the source gas of the group III element and the source gas of the group V element can be arbitrarily changed depending on the compound semiconductor grown on the substrate 8. , The dummy gas introduced into the third gas line includes these group III elements and V
The gas should be changed to the optimal gas for the group element gas. Here, the dummy gas introduced into the fourth gas line is always an inert gas.

As described above, according to this embodiment, it is possible to easily set the optimum gas composition and the optimum growth conditions for growing a uniform crystal uniformly on the growth surface of the substrate 8. Horizontal MOCV for multiple substrates
D device can be obtained.

As described above, one embodiment of the present invention has been specifically described. However, the present invention is not limited to the above-described embodiment, and various modifications based on the technical idea of the present invention are possible. .

For example, the numerical values, materials, and structures given in the above-described embodiment are merely examples, and different numerical values, materials, and structures may be used as needed.

Specifically, for example, in the above-described embodiment, the gas constricted portions 10a to 13a are provided separately from each other along the circumferential direction.
As the structure of Oa to 13a, a slit-like structure or a sintered body of fine particles may be used. Further, for example, in the above-described embodiment, the gas inflow terminals are connected to the gas passage walls 10 to 10.
13, the source gas and the dummy gas are introduced into each of the first gas line 14 to the fourth gas line 17 through their gas inflow terminals. A raw material gas or a dummy gas may be introduced by connecting a pipe or the like directly to the horizontal flow path of the lines 11 to the fourth gas line 14, and in this case, the raw material gas and the dummy gas are more uniformly radiated in the horizontal flow path. Gas constricted portions 10a to 13
a can be optimized and designed.

For example, in the above-described embodiment, the susceptor 7 is made of SiC.
A carbon material coated with SiC may be used.

For example, in the above-described embodiment, the susceptor 7 fixed to the horizontal MOCVD apparatus is used.
An annular rotation ring 21 for rotating the ring is provided on the outer periphery of the rotating annular plate 20, and a gear 21 a is provided on the inner periphery of the rotation ring 21, but for rotating the susceptor 7, A disk provided with a gear on the outer circumference may be provided on the inner circumference of the rotary annular plate 20. In this case, a gear 7g provided on the outer circumference of the susceptor 7 and the outer circumference of the disk are provided. By moving the susceptor 7 along the outer periphery of the disk while meshing with the gear, the susceptor 7 can be rotated on its own. Further, for example, in the above-described embodiment, the gear 7g and the gear 21a are directly meshed, but the third gear is interposed between the gear 7g and the gear 21a.
And the gear 7g and the gear 21a may be connected via the third gear. In this case as well, the susceptor 7 is rotated by rotating the rotary annular plate 20. Can be. Further, for example, in the above-described embodiment, a method of transmitting power to the rotation drive system 3 on an inner peripheral portion of the rotating annular plate 20 is employed as a driving method for rotating the rotating annular plate 20. , Rotating ring plate 2
It is also possible to adopt a method of transmitting power to the outer periphery of the zero and rotating it.

For example, in the above-described embodiment, the cross-sectional shape of the light reflecting surface in the radial direction of the lamp house 31 is a parabola, but the cross-sectional shape may be an ellipse instead of a parabola. In this case, the annular quartz tube lamp 30 is provided at one focal point of the ellipse, and the other focal point is located several cm above the susceptor 7.
This also allows the plurality of susceptors 7 arranged on the circumference to be
Can be uniformly heated. Also, the rotating annular plate 20
It is also possible to install a light reflection plate on the top, so that the heating efficiency when heating the susceptor can be further increased.

Further, for example, in the above-described embodiment, between the portion of the groove 40 b of the exhaust gas constriction portion 40 and the portion of the exhaust gas reservoir portion 41, on the circumference concentric with the exhaust gas constriction portion 40, A plurality of holes may be provided at regular intervals. At this time, the diameter of the hole is, for example, 20 mm, and the interval between the holes is, for example, 40 mm.

[0083]

As described above, according to the first aspect of the present invention, since the gas narrowing portion is provided in the passage through which the reactant gas flows, the reactant gas can flow uniformly on the growth surface of the substrate. Therefore, a uniform crystal can be grown on the substrate with a uniform film thickness.

According to the second aspect of the present invention, an annular rotary plate having a plurality of openings for installing a susceptor and having heat insulation properties constitutes a part of a passage wall of a gas passage. By doing so, a uniform crystal can be grown with a uniform thickness on the growth surface of the substrate.

According to the third aspect of the present invention, the susceptor comprises a substrate holding section for holding one substrate and a substrate heating section for transferring heat to the substrate to heat it. Since only the substrate can be heated, the thermal efficiency can be improved and the growth cost can be reduced.

According to the fourth aspect of the present invention, the heating means comprises an annular light source and an annular reflecting mirror for condensing light emitted from the light source on the susceptor. Accordingly, since only the susceptor can be heated, the thermal efficiency in heating the susceptor can be improved.

According to the fifth aspect of the present invention, since the gas exhaust means has the exhaust gas constriction, the gas flow rate can be made uniform on the growth surface of any substrate. Crystals can be grown uniformly on the growth surface of the substrate.

Further, according to the sixth aspect of the present invention, since the apparatus has the top plate which can be attached and detached and the top plate supporting means for supporting the top plate, it is possible to attach and detach the substrate to the susceptor. The removal from the susceptor can be easily performed, and the mechanical strength of the top plate can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a horizontal MOCVD apparatus according to an embodiment of the present invention.

FIG. 2 is a radial sectional view showing a gas line / gas supply system according to an embodiment of the present invention.

FIG. 3 is a sectional view taken along a circumferential direction of a gas constricted portion according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a rotating annular plate provided with a susceptor according to an embodiment of the present invention.

FIG. 5 is a plan view and a sectional view showing a susceptor according to an embodiment of the present invention.

FIG. 6 is a plan view showing a susceptor and a rotation ring according to an embodiment of the present invention.

FIG. 7 is a sectional view showing a heating device according to an embodiment of the present invention.

FIG. 8 is a sectional view of a gas discharge unit according to one embodiment of the present invention.

FIG. 9 is a sectional view showing a top plate according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... gas line / gas supply system, 2 ... gas discharge part, 3 ... rotation drive system, 4 ... susceptor / rotational ring plate, 5 ... top plate, 6 ... heating Apparatus, 7: susceptor, 8: substrate, 20: rotating circular plate

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/205 H01L 21/205 // H01L 33/00 33/00 C H01S 3/18 H01S 3/18

Claims (32)

[Claims] 1. A chemistry comprising: a plurality of susceptors disposed on one circumference; a plurality of gas passages for supplying a reaction gas toward the susceptor; and a heating means for heating the susceptor. The chemical vapor deposition apparatus according to claim 1, wherein at least one of the plurality of gas passages is provided with a gas constriction on a circumference concentric with the circumference. 2. The chemical vapor deposition apparatus according to claim 1, wherein the gas constriction is provided in all of the plurality of gas passages. 3. The plurality of gas passages include a first gas passage for a group III element source gas and a second gas passage for a group V element source gas. Second
2. The gas passage of claim 1, wherein the gas passage and the gas passage converge at an angle downstream of the gas constriction.
A chemical vapor deposition apparatus as described. 4. The chemical vapor deposition apparatus according to claim 3, wherein said angle is not less than 10 ° and not more than 90 °. 5. A gas passage for a source gas of a group III element, a second gas passage for a source gas of a group V element, and a gas passage for an inert gas carrier gas. A third gas passage, and a fourth gas passage for a carrier gas of an inert gas containing hydrogen, wherein the third gas passage and the fourth gas passage are arranged around the susceptor in the first gas passage. 2. The chemical vapor deposition apparatus according to claim 1, wherein said gas passage and said second gas passage are merged substantially in parallel with each other. 6. A structure according to claim 5, wherein a cross-sectional area of the gas passage after the merge of the plurality of gas passages decreases from an upstream side to a downstream side around the susceptor. Chemical vapor deposition equipment. 7. The chemical vapor deposition apparatus according to claim 5, wherein a surface of the gas passage after the merging facing the susceptor is inclined with respect to the susceptor. 8. A chemical having a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating means for heating the susceptor. In the vapor phase growth apparatus, an annular rotating plate provided with a plurality of openings for installing the susceptor forms a part of a passage wall of one of the plurality of gas passages. Chemical vapor deposition equipment. 9. The chemical vapor deposition apparatus according to claim 8, wherein when the susceptor is installed in the opening of the rotating plate, a lower surface of the susceptor forms a part of the passage wall. . 10. The susceptor is configured to revolve by rotation of the rotating plate.
A chemical vapor deposition apparatus as described. 11. The susceptor has a first gear on an outer peripheral portion, the first gear being connected to a second gear fixed to the chemical vapor deposition apparatus, and 9. The chemical vapor deposition apparatus according to claim 8, wherein the susceptor is configured to rotate by rotating the first gear by the rotation of the first gear. 12. The chemical vapor deposition apparatus according to claim 11, wherein the second gear is provided on an inner peripheral portion of the annular plate. 13. The chemical vapor deposition apparatus according to claim 11, wherein said second gear is provided on an outer peripheral portion of a circular plate. 14. The chemical vapor deposition apparatus according to claim 8, wherein said rotating plate has thermal insulation. 15. The apparatus according to claim 8, wherein a lower surface of said rotating plate and a lower surface of said susceptor are substantially coplanar.
A chemical vapor deposition apparatus as described. 16. A chemistry having a plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, and a heating means for heating the susceptor. In the vapor phase growth apparatus, the susceptor includes a substrate holding section having an opening for installing a substrate, and a substrate heating section for transmitting heat to the substrate to heat the substrate. . 17. The chemical vapor deposition apparatus according to claim 16, wherein said substrate holding portion has a projection for holding said substrate. 18. The apparatus according to claim 18, wherein the substrate heating section is fixed in contact with a substrate installed on the substrate holding section by its own weight, and is detachably provided to the substrate holding section. Item 17. A chemical vapor deposition apparatus according to Item 16. 19. A chemistry comprising: a plurality of susceptors arranged on one circumference; a plurality of gas passages for supplying a reaction gas toward the susceptor; and a heating means for heating the susceptor. In the vapor phase epitaxy apparatus, the heating means comprises an annular light source, and an annular reflecting mirror for condensing light emitted from the light source on the susceptor. Growth equipment. 20. The chemical vapor deposition apparatus according to claim 19, wherein a cross section in the radial direction of the annular reflecting mirror is an ellipse whose focal point is located on the annular light source. 21. The chemical vapor deposition apparatus according to claim 19, wherein a cross section in a radial direction of said annular reflecting mirror is a parabola whose focal point is located at said annular light source. 22. The chemical vapor deposition apparatus according to claim 19, wherein the heating means and the reaction system in which the susceptor is located are separated by a light passing plate through which light passes. 23. The apparatus according to claim 22, wherein an inside of said heating means is filled with an inert gas, and a portion between said susceptor and said light passage plate is filled with an inert gas. A chemical vapor deposition apparatus as described. 24. The chemical vapor deposition apparatus according to claim 22, further comprising anti-fog means for preventing the light passing plate from fogging. 25. The chemical vapor deposition apparatus according to claim 22, wherein said light passing plate is made of quartz. 26. An annular rotating plate provided with a plurality of openings for installing the susceptor, wherein two cylinders having different radii on the rotating plate are concentric with the rotating plate. 20. The chemical vapor deposition apparatus according to claim 19, wherein the surface on the side where the opening of the cylinder exists constitutes a light reflecting surface. 27. A plurality of susceptors arranged on one circumference, a plurality of gas passages for supplying a reaction gas toward the susceptor, a heating unit for heating the susceptor, and the reaction A chemical vapor deposition apparatus having gas exhaust means for exhausting gas, wherein the gas exhaust means has an exhaust gas constriction. 28. The chemical vapor deposition apparatus according to claim 27, wherein said gas exhaust means further has an exhaust gas reservoir downstream of said exhaust gas constriction. 29. The chemical vapor deposition apparatus according to claim 27, wherein the exhaust gas confinement portion is constituted by a thin plate having a plurality of minute openings and a groove. 30. A chemistry comprising: a plurality of susceptors arranged on one circumference; a plurality of gas passages for supplying a reaction gas toward the susceptor; and a heating means for heating the susceptor. In a vapor phase epitaxy apparatus, a chemical gas comprising: a top plate that can be attached and detached to separate the reaction system in which the susceptor is placed and the heating means; and a top plate supporting means that supports the top plate. Phase growth equipment. 31. The chemical vapor deposition apparatus according to claim 30, wherein the top plate comprises a portion made of quartz and a portion made of metal. 32. The chemical vapor deposition apparatus according to claim 30, wherein said top plate supporting means is a central axis of a rotating means for rotating a rotating plate holding said susceptor.