JPH09306851A - Decompression exhaust system and decompression vapor-phase treating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decompression exhaust system and decompression vapor- phase treating apparatus good in pressure controllability and high in safety and availability of the apparatus. SOLUTION: A decompression exhaust system having a vacuum pump 2 with a butterfly valve 1 and two exhaust units having mutually connected intakes is connected to a reactor 11 of a decompression MOCVD(metal org. compd. chemical vapor deposition) apparatus. For controlling the growth pressure in the reactor 11 being evacuated, both exhaust units are used at the same time. If required, an N2 gas is fed into exhausting pipings 3 at the upstream of the valves 1 of the exhaust units to reduce nearly to zero between the pressure difference at both exhaust nits. In other example, a similar decompression exhaust system is connected to two or more reactors 11 of a decompression MOCVD apparatus.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reduced pressure exhaust system and a reduced pressure gas phase treatment apparatus.

[0002]

2. Description of the Related Art A reduced pressure vapor phase treatment apparatus, in particular, a reduced pressure metal organic chemical vapor deposition (MOCVD) apparatus, has a reduced pressure exhaust system for reducing the pressure in the reactor and controlling the growth pressure in the reactor. ing. FIG. 6 is a schematic diagram showing a configuration example of this conventional reduced pressure exhaust system.

As shown in FIG. 6, a conventional vacuum exhaust system has a vacuum pump 102 having a butterfly valve 101. Where butterfly valve 1
01 has a variable opening and closing angle, and has a role as a pressure control device. As the vacuum pump 102, for example, a rotary pump or a dry pump is used. Reference numeral 103 indicates an exhaust pipe.

Reference numeral V ₁₀₁ indicates a gate valve, and reference numeral V ₁₀₂ indicates an air-operated valve. These gate valve V ₁₀₁ and air operated valve V
₁₀₂ is provided in the exhaust pipe 103 on the upstream side of the butterfly valve 101. Here, the gate valve V ₁₀₁
Is for opening and closing the main exhaust path, and the air-operated valve V ₁₀₂ is for opening and closing the auxiliary exhaust path.

A pressure gauge 104 for monitoring the pressure is provided in the exhaust pipe 103 on the intake side of the reduced pressure exhaust system.
Is provided. The output of the pressure gauge 104 is supplied to a pressure controller (not shown). This pressure controller is for adjusting the opening / closing angle of the butterfly valve 101 based on the pressure signal from the pressure gauge 104. Reference numeral 105 indicates a bypass pipe. The bypass pipe 105 is branched from the exhaust pipe 103 on the intake side of the reduced pressure exhaust system. The bypass pipe 105 is provided with an air operate valve V ₁₀₃ and a differential pressure gauge 106. Here, the opening / closing of the air operate valve V ₁₀₃ is controlled by the differential pressure gauge 106.

When this conventional decompression exhaust system constructed as described above is used in a decompression MOCVD apparatus,
The exhaust pipe 103 on the intake side of the reduced pressure exhaust system is
The exhaust pipe 103 and the bypass pipe 105 on the exhaust side are connected to a reactor 107 of a low-pressure MOCVD device, and connected to an abatement device (not shown).

Next, an example of the method for reducing the pressure of the reactor 107 by the above-described conventional vacuum exhaust system will be described.
The reactor 107 before being depressurized has a predetermined flow rate of hydrogen (H
₂ ) A carrier gas such as a gas is introduced, and the pressure inside the reactor 107 is set to about atmospheric pressure. At this time, in the conventional reduced pressure exhaust system, the gate valve V ₁₀₁ and the air operate valve V ₁₀₂ of the exhaust pipe 103 are closed, and the air operate valve V ₁₀₃ of the bypass pipe 105 is opened. Therefore, the carrier gas introduced into the reactor 107 is introduced into the abatement device (not shown) through the bypass pipe 105.

Therefore, when decompressing the reactor 107, first, the air operate valve V ₁₀₃ is closed and the bypass pipe 105 is shut off. Almost at the same time, the air operate valve V ₁₀₂ is opened and the reactor 107 is gradually depressurized by the vacuum pump 102. After this, the gate valve V ₁₀₁ is opened, and the reactor 107 is depressurized in earnest. Further, by starting the operation of the butterfly valve 101, the reactor 107 is depressurized to the growth pressure. Further, when the growth pressure fluctuates, feedback is applied to the butterfly valve 101 by a pressure controller (not shown). Thereby, the reactor 1
The growth pressure in 07 is controlled to be almost constant.

[0009]

However, when controlling the growth pressure by depressurizing the reactor 107 of the depressurized MOCVD apparatus using the above-mentioned conventional depressurized exhaust system,
There is a problem that the growth pressure causes small fluctuations of a predetermined cycle due to the responsiveness of the butterfly valve 101 and the like. Therefore, in the conventional low pressure MOCVD apparatus to which the conventional low pressure exhaust system is connected, there is a problem that the growth of the compound semiconductor becomes unstable due to the fluctuation of the growth pressure. In particular, when the capacity of the reactor 107 becomes large like the reactor 107 capable of charging a plurality of large-diameter wafers, a large butterfly valve 101 has to be used because of the exhaust capacity of the vacuum pump 102. However, delicate control of the growth pressure inside the reactor 107 must be difficult to some extent.

In the conventional vacuum exhaust system described above, if the vacuum pump 102 is stopped during operation for some reason, the reduced pressure inside the reactor 107 cannot be maintained. Vacuum pump 102 when a large flow of carrier gas is being introduced into the reactor 107, such as when growth is taking place in the reactor.
If is stopped, the pressure in the reactor 107 will eventually reach atmospheric pressure or higher. At this time, although the air operate valve V ₁₀₃ is opened under the control of the differential pressure gauge 106 and the carrier gas starts to flow in the bypass pipe 105,
Since the reactor 107 is in a pressurized state, the reactor 107 may be burdened. As described above, when the conventional decompression exhaust system is used in the decompression MOCVD apparatus, there is a problem in safety of the decompression MOCVD apparatus.

Further, when performing maintenance such as replacement or repair of the vacuum pump 102, it is necessary to stop the operation of the low pressure MOCVD apparatus, which causes a problem that the operation efficiency is reduced.

In the above, the conventional decompression exhaust device is operated under the decompression MOC
Regarding the case of using it in a VD apparatus, the above-mentioned problem may occur not only in the case of using the low pressure MOCVD apparatus but also in the case of using it in other low pressure vapor phase processing apparatus such as a diffusion apparatus and an annealing apparatus.

Therefore, an object of the present invention is to provide a reduced pressure exhaust system and a reduced pressure gas phase treatment apparatus which have good pressure controllability, and are highly safe and have high operating efficiency.

[0014]

In order to achieve the above object, the reduced pressure exhaust system according to the first invention of the present invention comprises:
It is characterized in that it has a plurality of exhaust means having a vacuum pump provided with a pressure control device, and the intake sides of the plurality of exhaust means are connected to each other.

A reduced pressure gas phase treatment apparatus according to a second aspect of the present invention has a plurality of processing chambers and a reduced pressure exhaust system connected to the plurality of processing chambers, and the reduced pressure exhaust system includes a pressure control device. A plurality of exhaust means having a vacuum pump, and the intake sides of the plurality of exhaust means are connected to each other,
In addition, the intake side of the plurality of exhaust means is connected to each of the plurality of processing chambers via the first cutoff valve.

A reduced pressure gas phase treatment apparatus according to a third aspect of the present invention comprises a first treatment chamber and a second treatment chamber, and a reduced pressure exhaust system connected to the first treatment chamber and the second treatment chamber. And a reduced pressure exhaust system having a first exhaust means and a second exhaust means having a vacuum pump provided with a pressure control device, and an intake side of the first exhaust means and the second exhaust means is The first exhaust means and the second exhaust means are connected to each other and the intake sides of the first exhaust means and the second exhaust means are connected to each other via the first cutoff valve.
Is connected to each of the processing chamber and the second processing chamber.

A reduced pressure gas phase treatment apparatus according to a fourth aspect of the present invention has a plurality of processing chambers and a reduced pressure exhaust system connected to each of the plurality of processing chambers via a first shutoff valve. The reduced pressure exhaust system is characterized in that it has a plurality of exhaust means having a vacuum pump provided with a pressure control device, and that the intake sides of the plurality of exhaust means are connected to each other.

A reduced pressure gas phase processing apparatus according to a fifth aspect of the present invention is a first processing chamber and a second processing chamber, and a first shut-off valve in each of the first processing chamber and the second processing chamber. A first reduced pressure exhaust system and a second reduced pressure exhaust system that are connected via the first reduced pressure exhaust system and the second reduced pressure exhaust system, the first reduced pressure exhaust system and the second reduced pressure exhaust system having a vacuum pump including a pressure control device. It is characterized in that it has one exhaust means and second exhaust means, and that the intake sides of the first exhaust means and the second exhaust means are connected to each other.

According to the present invention constructed as described above, a plurality of exhaust means having a vacuum pump having a pressure control device are provided, and the intake sides of these plurality of exhaust means are connected to each other. The pressure can be reduced by simultaneously using the vacuum pumps of a plurality of exhaust means. This improves the controllability of pressure. Further, even if the vacuum pump of one of the plurality of exhaust means is stopped during the depressurization,
A reduced pressure state can be maintained by a vacuum pump of another exhaust means. Furthermore, if at least one exhaust means is in operation, other exhaust means can be replaced, repaired, or otherwise maintained.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. First, the first of the present invention
An embodiment will be described. FIG. 1 shows a first embodiment of the present invention.
2 is a schematic diagram showing a configuration example of a reduced pressure exhaust system according to the embodiment of FIG. As shown in FIG. 1, the reduced pressure exhaust system has two exhaust units. Each of these two exhaust units has a vacuum pump 2 with a butterfly valve 1. Where butterfly valve 1
The opening / closing angle of the is variable and has a role as a pressure control device. As the vacuum pump 2, for example, a rotary pump or a dry pump is used. Code 3
Indicates an exhaust pipe. Reference numeral V ₁ indicates a gate valve, and reference numeral V ₂ indicates an air operated valve.
These gate valve V ₁ and air operated valve V ₂ are the butterfly valves 1 of the respective exhaust units.
Is provided in the exhaust pipe 3 on the upstream side. Here, the gate valve V ₁ is for opening and closing the main exhaust path, and the air-operated valve V ₂ is for opening and closing the auxiliary exhaust path.

Further, each exhaust unit has a gas introduction pipe 4 whose one end is connected to the exhaust pipe 3 on the upstream side of the butterfly valve 1. This gas introduction pipe 4
The other end is connected to a gas cylinder (not shown) containing N ₂ gas, for example. An air operate valve V ₃ and a mass flow controller 5 are provided in the gas introduction pipe 4. Here, the air operated valve V
₃ is used to perform the opening and closing of the gas inlet tube 4, the mass flow controller 5 is for controlling the flow rate of N ₂ gas flowing through the gas inlet tube 4.

Each exhaust unit is constructed as described above. Also, in this reduced pressure exhaust system, in order to monitor the differential pressure between the two exhaust units,
A differential pressure gauge 6 is connected between the exhaust pipes 3 on the upstream side of the butterfly valve 1 of these two exhaust units. The output of the differential pressure gauge 6 is supplied to the mass flow controller 5 of each exhaust unit. Further, in this reduced pressure exhaust system, the intake sides of the two exhaust units are connected to each other. In this case,
The exhaust sides of the two exhaust units are also connected to each other.

A pressure gauge 7 for monitoring the pressure is provided in the exhaust pipe 3 on the intake side of the reduced pressure exhaust system. The output of the pressure gauge 7 is supplied to a pressure controller (not shown). The control signal of this pressure controller is supplied to each of the butterfly valves 1 of the two exhaust units. As a result, according to the signal from the vacuum gauge 7, each butterfly valve 1
It is possible to adjust the opening and closing angle of. Code 8
Indicates bypass piping. This bypass pipe 8 is
It branches from the exhaust pipe 3 on the intake side of the reduced pressure exhaust system. The bypass pipe 8 is provided with an air operated valve V ₄ and a differential pressure gauge 9. Here, the opening / closing of the air operate valve V ₄ is controlled by the differential pressure gauge 9.

When the decompression exhaust system configured as described above is used in, for example, a decompression MOCVD apparatus, the exhaust pipe 3 on the intake side of the decompression exhaust system is
The exhaust pipe 3 and the bypass pipe 8 on the exhaust side are connected to a reactor 11 of a low-pressure MOCVD device, and connected to a detoxification device (not shown). Further, if necessary, a dust filter (not shown) may be provided in order to suppress the adverse effect of the product from the reactor 11 on the vacuum pump 2.

In this depressurized exhaust system, the vacuum pumps 2 of the two exhaust units have the same exhaust capacity. Also,
The exhaust capacity of each vacuum pump 2 is independent of that of the reactor 1.
1 is selected as the exhaust capacity capable of reaching a predetermined growth pressure.

Next, an example of the depressurizing method of the reactor 11 by the depressurizing exhaust system constructed as described above will be described. A carrier gas such as H ₂ gas having a predetermined flow rate is introduced into the reactor 11 before being depressurized, and the internal pressure of the reactor 11 is set to almost atmospheric pressure. At this time, in this reduced pressure exhaust system, the gate valve V _{1, the} air operate valve V ₂ , and the air operate valve V ₃ of the two exhaust units are all closed.
The air-operated valve V ₄ of the bypass pipe 8 is opened. Therefore, the carrier gas introduced into the reactor 11 is introduced into the abatement device (not shown) through the bypass pipe 8.

In this depressurized exhaust system, when depressurizing the reactor 11, it is possible to use two vacuum pumps 2 at the same time or to use only one of them. Here, a case where two vacuum pumps 2 are used simultaneously will be described. In this case, the corresponding valves of the two exhaust units are operated simultaneously. That is, when depressurizing the reactor 11, first, the air operate valve V ₄ is closed and the bypass pipe 8 is shut off. Almost at the same time, the air operated valves V ₂ of the two exhaust units are opened, and the pressure reduction of the reactor 11 by the two vacuum pumps 2 is started. Thereby, the reactor 1
The pressure inside 1 gradually decreases.

The inside of the reactor 11 has a predetermined pressure,
Specifically, for example, about 2.0 × 10 ⁴ Pa (150To
When it reaches rr), the flow rate of the carrier gas supplied to the reactor 11 is increased in the low pressure MOCVD apparatus.
At the same time, in this reduced pressure exhaust system, the gate valves V ₁ of the two exhaust units are opened, and the inside of the reactor 11 is brought into a full-scale reduced pressure state. At this time, the air operate valve V ₂ may remain open.

Then, the pressure inside the reactor 11 further decreases, and for example, about 1.3 × 10 ⁴ Pa (100 Tor)
r) In the low pressure MOCVD apparatus, when
The flow rate of the carrier gas supplied to the reactor 11 is further increased to a finally required flow rate. At the same time, in this reduced pressure exhaust system, in order to reduce the pressure in the reactor 11 to the pressure required for growth (growth pressure), a pressure signal from the pressure gauge 7 is supplied to a pressure controller (not shown). Under control, the operation of the butterfly valves 1 of the two exhaust units starts.

As a result, the pressure in the reactor 11 is automatically controlled and eventually reaches a predetermined growth pressure, specifically, about 9.8 × 10 ³ Pa (75 Torr).
Further, when the growth pressure in the reactor 11 fluctuates, the two butterfly valves 1
To give feedback to. Thereby, the growth pressure in the reactor 11 is controlled to be substantially constant.

Further, in this depressurized exhaust system, at the same time as the operation of the butterfly valve 1 is started,
An air operated valve V ₃ that shuts off the gas introduction pipe 4.
Is opened, and N ₂ gas is introduced to the upstream sides of the butterfly valves 1 of the two exhaust units, respectively. in this case,
The mass flow controller 5 controls the flow rate of the N ₂ gas introduced into each exhaust unit.
As a result, minute fluctuations in the growth pressure of the reactor 11 can be suppressed.

When the pressure balance between the two exhaust units is lost and a differential pressure is generated between the two exhaust units, the mass flow controller 5 is operated by the differential pressure gauge 6 according to the differential pressure.
N ₂ which is fed back to the upstream side of the butterfly valve 1 of each exhaust unit.
The flow rate of the gas is changed so that the pressure difference between the two exhaust units is controlled to be substantially zero. This allows
It is possible to prevent the one-sided pulling state by only one of the vacuum pumps 2. As described above, the reactor 11 is depressurized by this depressurized exhaust system.

According to this decompression exhaust system constructed as described above, it has two exhaust units having the vacuum pump 2 having the butterfly valve 1, and the intake sides of these two exhaust units are connected to each other. Therefore, the following effects can be obtained. That is, reactor 1
1 can be decompressed by using two vacuum pumps 2 at the same time, and the growth pressure in the reactor 11 can be controlled by using two butterfly valves 1. Therefore, the load on each vacuum pump 2 can be reduced. And the opening / closing angle of each butterfly valve 1 also becomes smaller. Therefore, a small signal can be fed back to the fluctuation of the growth pressure in the reactor 11, so that the fluctuation of the growth pressure can be suppressed. Thereby, the controllability of the growth pressure in the reactor 11 can be improved as compared with the conventional vacuum exhaust system. Further, since the controllability of the growth pressure is improved, it is possible to stably grow the compound semiconductor in the low pressure MOCVD apparatus.

Further, according to this reduced pressure exhaust system, the vacuum pumps 2 of the two exhaust units are provided in the reactor 1 respectively.
1 has an exhaust capacity capable of reaching the growth pressure, so that even if the vacuum pump 2 of one exhaust unit is stopped for some reason during the depressurization of the reactor 11, the vacuum pump 2 of the other exhaust unit can be used. The reactor 11 can be returned to the original reduced pressure state in a short time. As a result, the reactor 11
Therefore, the safety of the low pressure MOCVD apparatus can be improved.

Further, since the vacuum pump 2 of each exhaust unit can be used independently, it does not significantly affect the operation of the low pressure MOCVD apparatus to which this low pressure exhaust system is connected, and either one of the vacuum pumps can be operated. Maintenance such as replacement and repair of the pump 2 can be performed. As a result, the operating efficiency of the low pressure MOCVD apparatus can be improved.

Next, a second embodiment of the present invention will be described. FIG. 2 shows a decompression MO according to the second embodiment.
It is an approximate line figure showing the example of composition of a CVD device and its pressure reduction exhaust system. As shown in FIG. 2, this low pressure MOCVD
The apparatus consists of two reactors 11 and these two reactors 1.
1 and a reduced pressure exhaust system similar to that of the first embodiment.

That is, the reduced pressure exhaust system of this reduced pressure MOCVD apparatus has two exhaust units similar to the exhaust unit of the reduced pressure exhaust system according to the first embodiment,
The intake sides of these two exhaust units are connected to each other. In this case, in FIG. 2, the intake side of the left exhaust unit is connected to the left reactor 11 via the gate valve V _11, and the intake side of the right exhaust unit is connected to the right side via the gate valve V _12. It is connected to the reactor 11. The intake sides of these two exhaust units are connected to each other via gate valves V ₁₃ and V ₁₄ .

Further, the reduced pressure exhaust system has a pressure gauge 7 for two reactors 11 and a bypass pipe 8. The outputs of the two pressure gauges 7 are supplied to a pressure controller (not shown). The other points are similar to those of the depressurized exhaust system according to the first embodiment, and therefore the description thereof will be omitted.

Next, the reduced pressure M constructed as described above.
An example of the method of decompressing the two reactors 11 of the OCVD device will be described. Here, the case of reducing the pressure of the left reactor 11 in FIG. 2 will be described, but the same applies to the case of reducing the pressure of the right reactor 11 in FIG.

That is, when the pressure of the reactor 11 on the left side in FIG. 2 is reduced, the gate valve V ₁₂ is closed and the gate valves V ₁₁ , V ₁₃ and V ₁₄ are opened. At this time, the depressurized exhaust system according to the first embodiment is equivalently connected to the left-side reactor 11 to be depressurized. As a result, the reactor 11 on the left side in FIG. 2 is depressurized by the same method as the depressurizing method according to the first embodiment. Here, the signal required for the pressure controller (not shown) to adjust the opening / closing angle of the butterfly valve 1 is supplied from the pressure gauge 7 connected to the left reactor 11 to be depressurized. The carrier gas introduced into the right reactor 11 which is not depressurized is supplied to a detoxification device (not shown) through the bypass pipe 8 connected to the right reactor 11.

This reduced pressure MOCV constructed as described above.
According to the D device, in addition to the same effects as the first embodiment, the following effects can be obtained. That is, according to this low pressure MOCVD apparatus, since the two reactors 11 are provided, it is possible to grow the compound semiconductor by alternately depressurizing these two reactors 11. As a result, while the one reactor 11 is on standby, the other reactor 11 can be depressurized to perform growth.
The effect that the operation efficiency of the device is further improved can be obtained.

Next, a third embodiment of the present invention will be described. FIG. 3 shows a decompression MO according to the third embodiment.
It is an approximate line figure showing the example of composition of a CVD device and its pressure reduction exhaust system. As shown in FIG. 3, this low pressure MOCVD
The device comprises two reactors 11 and two vacuum exhaust systems 12 connected to each of these two reactors 11. Here, each of these two decompression exhaust systems 12 corresponds to a portion surrounded by a chain line in FIG. In addition, in FIG. 3, the intake side of the reduced pressure exhaust system 12 on the left side is a gate valve V ₁₁
Is connected to the reactor 11 on the left side, and the intake side of the reduced pressure exhaust system 12 on the right side is connected to the reactor 11 on the right side via a gate valve V ₁₂ . Further, the intake side of these two reduced pressure exhaust systems 12 is connected to the gate valve V
₁₃ and V ₁₄ are connected to each other. Since the other points are the same as those of the low pressure MOCVD apparatus according to the second embodiment, description thereof will be omitted.

Next, this reduced pressure M constructed as described above is used.
An example of the method of decompressing the two reactors 11 of the OCVD device will be described. Here, the case of reducing the pressure of the left reactor 11 in FIG. 3 will be described, but the same applies to the case of reducing the pressure of the right reactor 11 in FIG.

That is, when the pressure of the reactor 11 on the left side in FIG. 3 is reduced, the gate valves V ₁₂ , V ₁₃ and V ₁₄ are closed and the gate valve V ₁₁ is opened. At this time, the depressurized exhaust system according to the first embodiment is equivalently connected to the left-side reactor 11 to be depressurized. As a result, the reactor 11 on the left side in FIG. 3 is depressurized by the same method as the depressurizing method according to the first embodiment. Since the other points are the same as those in the second embodiment, description thereof will be omitted.

Further, in this depressurized MOCVD apparatus, even if one of the depressurized exhaust systems 12 becomes unusable due to a failure or the like, the gate valves V ₁₃ and V _{13 are used} .
₁₄ is opened so that the other vacuum exhaust system 12
Can be used to depressurize the two reactors 11. At this time, each reactor 11 is depressurized by the same method as the depressurizing method described above. According to this low pressure MOCVD apparatus, the same effect as that of the low pressure MOCVD apparatus according to the second embodiment can be obtained.

Next explained is the fourth embodiment of the invention. FIG. 4 shows a reduced pressure MO according to the fourth embodiment.
It is an approximate line figure showing the example of composition of a CVD device and its pressure reduction exhaust system. As shown in FIG. 4, this low pressure MOCVD
The apparatus consists of three reactors 11 and these three reactors 1.
1 and a reduced pressure exhaust system similar to that of the second embodiment. In this case, the reduced pressure exhaust system has three exhaust units similar to the exhaust unit of the reduced pressure exhaust system according to the first embodiment, and the intake sides of these three exhaust units are connected to each other.
Here, reference numerals V _{21 to} V ₂₇ indicate gate valves. In this case, the gate valve V ₂₁ ~V ₂₃ has the same role as the gate valve V _11, V ₁₂ in FIG. 2, the gate valve V ₂₄ ~V
₂₇ has a role similar to that of the gate valves V ₁₃ and V _{14 in} FIG. Since the other points are the same as those of the low pressure MOCVD apparatus according to the second embodiment shown in FIG. 2, description thereof will be omitted.

Next, this reduced pressure M constructed as described above is used.
An example of the method of decompressing the three reactors 11 of the OCVD device will be described. Here, the case where the left reactor 11 in FIG. 4 is depressurized will be described, but the same applies to the case where the central and right reactors 11 in FIG. 4 are depressurized.

That is, when the pressure of the reactor 11 on the left side in FIG. 4 is reduced, the gate valves V ₂₂ , V ₂₃ , V ₂₆ , V
₂₇ is closed and the gate valves V ₂₁ , V ₂₄ ,
V ₂₅ is opened. At this time, the left reactor 1 is depressurized
1 is equivalently connected to the reduced pressure exhaust system according to the first embodiment. As a result, the reactor 11 on the left side is depressurized by the same method as in the first embodiment. Since the other points are the same as those in the second embodiment, description thereof will be omitted. This decompression MOC
According to the VD device, the decompression MOCV according to the second embodiment
The same effect as the D device can be obtained.

Next explained is the fifth embodiment of the invention. FIG. 5 shows a decompression MO according to the fifth embodiment.
It is an approximate line figure showing the example of composition of a CVD device and its pressure reduction exhaust system. As shown in FIG. 5, this low pressure MOCVD
The apparatus consists of three reactors 11 and these three reactors 1.
1 and a reduced pressure exhaust system similar to that of the second embodiment. In this case, this decompression exhaust system has two exhaust units similar to the exhaust unit of the decompression exhaust system according to the first embodiment, and the intake sides of these two exhaust units are connected to each other.
That is, this low pressure MOCVD apparatus is the same as the low pressure MOCVD apparatus of the fourth embodiment shown in FIG.
Middle and right exhaust unit and gate valves V ₂₆ , V ₂₇
Is omitted. Others are the same as those of the low pressure MOCVD apparatus according to the fourth embodiment.
Description is omitted.

Next, this reduced pressure M constructed as described above.
An example of the method of decompressing the three reactors 11 of the OCVD device will be described. Here, the case of reducing the pressure of the left reactor 11 in FIG. 5 will be described, but the same applies to the case of reducing the pressure of the center and right reactors 11 in FIG.

That is, when the pressure of the reactor 11 on the left side in FIG. 5 is reduced, the gate valves V ₂₂ , V ₂₃ are closed and the gate valves V ₂₁ , V ₂₄ , V ₂₅ are opened. . At this time, with respect to the left side reactor 11 to be depressurized,
Equivalently, the reduced pressure exhaust system according to the first embodiment is connected. As a result, the reactor 11 on the left side is depressurized by the same method as the depressurizing method according to the first embodiment. Since the other points are the same as those in the second embodiment, description thereof will be omitted. This decompression MO
According to the CVD apparatus, the reduced pressure MOC according to the second embodiment
The same effect as the VD device can be obtained.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above embodiments, and various modifications based on the technical idea of the present invention are possible. For example, this invention is a reduced pressure MOCV.
In addition to the D apparatus, the present invention can be applied to other reduced pressure gas phase processing apparatuses such as a diffusion apparatus and an annealing apparatus.

The configurations and numerical values given in the above-mentioned first to fifth embodiments are merely examples, and the present invention is not limited to these. Specifically, for example, the butterfly valve 1 may be replaced with one having a function of performing pressure control similar to this. Further, the gate valves V ₁ , V _{11 to} V ₁₄ , V _{21 to} V _{27, the} air operated valves V _{2 to} V ₄ and the like can be replaced with those having the same function of shielding the exhaust pipe 3. .

[0054] Further, in the first to fifth embodiments described above, instead of N ₂ gas, H ₂ gas or argon (A
r) An inert gas such as gas may be introduced into the exhaust pipe 3 upstream of the gate valve 1 of each exhaust unit. Further, in some cases, these gases may be combined and introduced. For example, a gas with a high exhaust resistance such as N ₂ gas is introduced to perform rough pressure control, and H ₂
A finer pressure control may be performed by introducing a gas having a small exhaust resistance such as gas.

[0055]

As described above, according to the present invention, a plurality of exhaust means having a vacuum pump provided with a pressure control device are provided, and the intake sides of these plurality of exhaust means are connected to each other. , A vacuum pump 2 of a plurality of exhaust means
Can be used simultaneously to reduce the pressure. This allows
Since the controllability of the pressure inside the processing chamber is improved, the processing inside the processing chamber can be performed stably. Further, even if the vacuum pump of one of the plurality of evacuation means is stopped during the decompression of the processing chamber, the decompressed state can be maintained by the vacuum pump of the other evacuation means. The safety of the processing device can be increased. Furthermore, if at least one exhaust means is operating, it is possible to perform maintenance such as replacement and repair of other exhaust means without significantly affecting the operation of the reduced pressure gas phase treatment apparatus.
The operation efficiency of the reduced pressure gas phase treatment apparatus can be increased.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration example of a reduced pressure exhaust system according to a first embodiment of the present invention.

FIG. 2 is a reduced pressure MOCV according to a second embodiment of the present invention.
It is an approximate line figure showing the example of composition of D device and the decompression exhaust system.

FIG. 3 is a reduced pressure MOCV according to a third embodiment of the present invention.
It is an approximate line figure showing the example of composition of D device and the decompression exhaust system.

FIG. 4 is a reduced pressure MOCV according to a fourth embodiment of the present invention.
It is an approximate line figure showing the example of composition of D device and the decompression exhaust system.

FIG. 5 is a reduced pressure MOCV according to a fifth embodiment of the present invention.
It is an approximate line figure showing the example of composition of D device and the decompression exhaust system.

FIG. 6 is a schematic diagram showing a configuration example of a conventional reduced pressure exhaust system.

[Explanation of symbols]

1 ... Butterfly valve, 2 ... Vacuum pump, 3 ...
· Exhaust pipe, 4 ... gas inlet tube, 5 ... mass flow controller, 6 ... differential pressure gauge, 11 ... reactor, 12 ... vacuum exhaust system, V _1, V ₁₁ ~V ₁₄ ,
V ₂₁ ~V ₂₇ ··· gate valve, V ₂ ~V ₄ ··· air operated valve

Claims (13)

[Claims] 1. A decompression exhaust system comprising: a plurality of exhaust means having a vacuum pump provided with a pressure control device, wherein the intake sides of the plurality of exhaust means are connected to each other. 2. A differential pressure control device for detecting the differential pressure between the plurality of exhaust means on the upstream side of the pressure control device and making the differential pressure substantially zero. Item 1. The reduced pressure exhaust system according to Item 1. 3. The differential pressure control device introduces a differential pressure control gas to the upstream side of the pressure control device of the plurality of exhaust means, and changes the flow rate of the differential pressure control gas according to the differential pressure. The reduced pressure exhaust system according to claim 2, wherein the reduced pressure exhaust system is controlled. 4. A plurality of processing chambers, and a reduced pressure exhaust system connected to the plurality of processing chambers, wherein the reduced pressure exhaust system has a plurality of exhaust means having a vacuum pump provided with a pressure control device. And the intake sides of the plurality of exhaust means are connected to each other, and the intake sides of the plurality of exhaust means are connected to each of the plurality of processing chambers via a first shutoff valve. A characteristic reduced pressure gas phase treatment apparatus. 5. The plurality of exhaust means and the plurality of processing chambers are the same in number, the different exhaust means are connected to each of the plurality of processing chambers, and the plurality of exhaust means are connected to each other on the intake side. The reduced pressure gas phase treatment apparatus according to claim 4, wherein the reduced pressure gas phase treatment apparatus is connected via a second cutoff valve. 6. The reduced pressure gas phase processing apparatus according to claim 4, wherein the processing chamber has three or more processing chambers, and the exhaust means has two or more processing chambers. 7. The reduced pressure exhaust system has a differential pressure control device for detecting a differential pressure between the plurality of exhaust means on the upstream side of the pressure control device and making the differential pressure substantially zero. The reduced pressure gas phase treatment apparatus according to claim 4, wherein. 8. The differential pressure control device introduces a differential pressure control gas to an upstream side of the pressure control device of each of the plurality of exhaust means, and the differential pressure control gas is supplied in accordance with the differential pressure. The reduced pressure gas phase treatment apparatus according to claim 7, wherein the flow rate is controlled. 9. A first processing chamber and a second processing chamber, and a reduced pressure exhaust system connected to the first processing chamber and the second processing chamber, wherein the reduced pressure exhaust system has a pressure It has a first exhaust means and a second exhaust means having a vacuum pump provided with a control device, and the intake sides of the first exhaust means and the second exhaust means are connected to each other, and A first exhaust means and an intake side of the second exhaust means connected to each of the first processing chamber and the second processing chamber via a first shutoff valve. Gas phase treatment equipment. 10. A plurality of processing chambers, and a reduced pressure exhaust system connected to each of the plurality of processing chambers via a first shut-off valve, wherein the reduced pressure exhaust system includes a pressure control device. A reduced pressure gas phase treatment apparatus comprising a plurality of exhaust means having a vacuum pump, wherein the intake sides of the plurality of exhaust means are connected to each other. 11. The reduced pressure exhaust system has a differential pressure control device for detecting a differential pressure between the plurality of exhaust means on the upstream side of the pressure control device and making the differential pressure substantially zero. 11. The reduced pressure gas phase treatment apparatus according to claim 10. 12. The differential pressure control device introduces a differential pressure control gas to an upstream side of the pressure control device of each of the plurality of exhaust means, and the differential pressure control gas is introduced according to the differential pressure. The reduced pressure gas phase treatment apparatus according to claim 11, wherein the flow rate is controlled. 13. A first processing chamber and a second processing chamber, and a first reduced pressure exhaust connected to each of the first processing chamber and the second processing chamber via a first shutoff valve. A system and a second reduced pressure exhaust system, wherein the first reduced pressure exhaust system and the second reduced pressure exhaust system include a first exhaust means and a second exhaust having a vacuum pump provided with a pressure control device. A reduced pressure gas phase treatment apparatus comprising means, and the first exhaust means and the second exhaust means are connected to each other on their intake sides.