JPH07335557A - Gas exhaust pipe of semiconductor manufacturing device - Google Patents

Abstract

PURPOSE:To suppress the reduction in a device working efficiency due to the measurement of dust by achieving a stable measurement for a long time without interrupting the measurement of dust generated in a low-pressure container such as the CVD device in the exhaust system due to the cleaning, etc., of a dust monitor. CONSTITUTION:One portion of a pipe in the exhaust system of a CVD device is divided into two systems by making identical the type of valve and the structure such as the length, bending, and diameter of piping as much as possible. Further, a piping and a gas source 13 for purging inside the piping are connected to valves 14 and 15. A dust monitor is alternately fitted to sensor mounting parts 9 and 10 and the gas purge and dust monitor are removed before cleaning, thus achieving a continuous measurement of dust.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust pipe of a semiconductor manufacturing apparatus, and more particularly to measuring dust generated in a low pressure reactor such as a CVD device by a fine particle monitor or the like inserted in the exhaust pipe. The present invention relates to a suitable exhaust pipe structure.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, various vacuum processing apparatuses such as a CVD apparatus and an etching apparatus are used for forming a circuit on a wafer.

In the process of processing by these devices, minute dusts such as reaction products generated in the reaction vessel adhere to the wafer surface. This is the main cause of the decrease in yield in the semiconductor device manufacturing process. In order to reduce the amount of dust adhering to the surface of the wafer and improve the yield, it is necessary to know the dust generation state in the manufacturing apparatus and appropriately clean the reaction container.

Therefore, recently, there is a movement to detect dust generated in the reaction container by using a dust monitor or the like. However, in a CVD apparatus or the like, a large amount of dust is generated, and the dust rapidly adheres to a detection unit such as a dust monitor, which impairs the function as a monitor in a short time. Therefore, it is necessary to wash the sensor as needed. is there.

Conventionally, measures have been taken such as removing the monitor from the pipe and cleaning or replacing it. However, for example, as shown in JP-A-5-29263, in a general apparatus, since the exhaust system has a single piping, the operation of the semiconductor manufacturing apparatus must be stopped each time. However, there is a problem that the operating rate of the device is reduced.

[0006]

The problem to be solved by the present invention is to (1) reduce the dust contamination of the dust monitor by the reaction product, and (2) to simplify the cleaning of the dust monitor. This is to enable stable dust measurement with a dust monitor for a long period of time without reducing the operating rate of the device.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a plurality of exhaust system pipes to which a dust monitor is attached with the same (length, diameter) structure, and uses each exhaust pipe. A gas purge pipe was provided.

[0008]

In the exhaust system pipe of the present invention, when the dust monitor is contaminated by the plurality of pipes having the same structure, the dust monitor is cleaned by the following procedure.

(1) Attach a dust monitor to another pipe.

(2) The pipe in use is completely sealed by using valves before and after the monitor.

(3) The exhaust passage is switched to another pipe.

(4) Remove the dust monitor from the sealed pipe.

(5) Clean the dust monitor.

As a result, the device can be returned to the normal state in a short time, and the dust can be monitored almost continuously without breaking.

Further, since the plurality of exhaust pipes have the same structure, the conductance and the like of the exhaust pipes do not change. Therefore, there is almost no influence on the container pressure of the CVD reactor by exchanging the exhaust system pipes. Further, since the process of transporting dust from the manufacturing apparatus to the dust monitor does not change, there is almost no influence on measurement by switching the dust monitor.

Further, when the dust measurement is not performed, the pipe is completely sealed, and by using the pipe to which the dust monitor is not attached, it is possible to prevent the monitor from being contaminated when the dust measurement is not performed.

Further, by closing the valve upstream of the monitor and flowing the purge gas to the dust monitor or the like, it is possible to forcibly remove the dust adhering to the dust monitor without removing the dust monitor.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The contents of the present invention will be described below with reference to FIGS. 1 is an exhaust pipe of a semiconductor manufacturing apparatus according to a first embodiment of the present invention, FIG. 2 is an exhaust pipe of a semiconductor manufacturing apparatus according to a second embodiment of the present invention, and FIG. 3 is a third embodiment of the present invention. It is a block diagram of an exhaust pipe of a semiconductor manufacturing apparatus. Further, FIG. 4 is an explanatory diagram of dust measurement by a conventional dust monitor.

First, a device configuration and method for measuring dust with a general dust monitor will be briefly described with reference to FIG. As shown in FIG. 4, the raw material gas is introduced into the CVD reaction container 1 via the flow rate controller 19, the gas introduction pipe 2 and the gas supply head 12. On the other hand, the CVD reaction container 1
The inner wafer 3 is heated by the heater in the susceptor 11. Therefore, the raw material gas introduced into the CVD reaction container 1 causes a thermal reaction to form a thin film on the surface of the wafer 3. At the same time, a particulate reaction product (dust) is generated in the CVD reaction container 1, and the dust is exhausted to the outside by the vacuum pump 4 together with the gas. At this time, the gas exhaust pipe 16
The number and size of dust discharged to the outside are measured by the dust monitor 18 installed midway.

A first embodiment of the present invention will be described with reference to FIG. In this embodiment, as shown in FIG. 1, a part of the gas exhaust system piping is divided into two systems, and the sensor mounting portion 9 of the first piping is used.
Attach the dust monitor to. When measuring dust generated in the CVD reaction container 1, the valves 6 and 8 are closed and the valves 5 and 7 are opened. When the dust monitor is contaminated by dust and needs to be cleaned, first, the valves 5 and 7 are closed and the valves 6 and 8 are opened. Next, the dust monitor is removed from the sensor mounting portion 9 and the monitor is cleaned. Then, the dust monitor is attached to the sensor attachment portion 9 again, the valves 6 and 8 are closed, and the valves 5 and 7 are opened, so that the measurement of dust is continued.

By doing so, the dust monitor can be cleaned without stopping the CVD apparatus.
It is possible to suppress a decrease in device operating rate due to dust measurement.

A second embodiment of the present invention will be described with reference to FIG. In this embodiment, as shown in FIG. 2, a part of the piping of the exhaust system has two systems. In this case, the type of the first pipe (valves 5 and 7, the sensor mounting portion 9) and the second pipe (valves 6 and 8, the sensor mounting portion 10), the length of the pipe,
Make the bends, diameters, and other structures as uniform as possible.

First, the dust generated in the CVD reaction container 1
The first dust monitor is attached to the sensor attachment portion 9 of the pipe, the valves 5 and 7 are opened, and the valves 6 and 8 are closed to perform measurement. When the first dust monitor is contaminated with dust and needs to be cleaned, first, the second dust monitor is attached to the sensor mounting portion 10. Then, the valves 5 and 7 are closed and the valves 6 and 8 are opened to measure dust.
Next, the first dust monitor is removed from the sensor mounting portion 9 and cleaned as needed.

When the second dust monitor is contaminated with dust and needs to be cleaned, the second dust monitor is reattached to the sensor mounting portion 9, the valves 6 and 8 are closed, and the valves 5 and 7 are opened. By doing so, the dust is measured.

By repeating such operations, CV
The dust generated in the D reaction container 1 can be measured almost continuously except for a certain period when the pipes are switched, and a decrease in the device operating rate due to the dust measurement can be suppressed. Further, since the exhaust pipe has the same structure, the conductance of the exhaust pipe does not change. Therefore, the pressure of the CVD reaction container 1 does not change by exchanging the exhaust system pipe. Since the process of transporting dust from the container 1 to the dust monitor does not change, the influence of the dust monitor switching on measurement is eliminated.

A third embodiment of the present invention will be described with reference to FIG. In this embodiment, as shown in FIG. 3, a part of the piping of the exhaust system has two systems. In this case, the type of valve, the length of the pipe, the bend of the first pipe (valves 5, 7 and 14, sensor mounting portion 9) and the second pipe (valves 6, 8 and 15, sensor mounting portion 10), Make the diameter and other structures as uniform as possible. Further, a pipe for purging the inside of the pipe and a purge gas source 13 are connected to the valves 14 and 15.

First, the dust generated in the CVD reaction vessel 1
The first dust monitor is attached to the sensor attachment portion 9 of the pipe, the valves 5, 7 are opened, and the valves 6, 8, 14, 15 are closed, and measurement is performed. When the first dust monitor is contaminated with dust, the valve 5 is temporarily closed, and the purge gas source 13 and the valve 14 are used to purge the inside of the first pipe including the first dust monitor. , Clean. Then, the valve 5 is opened. As a result, dust measurement can be started again without removing the dust monitor. However, when this operation is repeated, the cleaning cannot be performed by the purging inside the pipe.

In such a case, the sensor mounting portion 10
Attach the second dust monitor to. And the valve 5,
The dust is measured by closing the valves 7, 14 and 15 and opening the valves 6 and 8. Next, the first dust monitor is removed from the sensor mounting portion 9 and cleaned as needed.

When the second dust monitor is contaminated with dust and needs to be cleaned, the valve 6 is temporarily closed and the purge gas source 13 and the valve 15 are used to include the second dust monitor. The inside of the second pipe is purged and cleaned. Then, the valve 6 is opened. As a result, the measurement of dust can be started again.

By repeating such an operation, CV
D Measurement of dust generated in the reaction container 1 for a long period of time,
Except for a fixed time of pipe switching and purging, it can be performed almost continuously, and it is possible to suppress a decrease in the equipment operation rate due to dust measurement. Further, since the exhaust pipe has the same structure, the conductance of the exhaust pipe does not change. Therefore, the pressure of the CVD reaction container 1 does not change by exchanging the exhaust system pipe. Since the process of transporting dust from the container 1 to the dust monitor does not change, the influence of the dust monitor switching on measurement is eliminated.

Here, as a semiconductor manufacturing apparatus, CVD is used.
Although the embodiments have been described by taking the apparatus as an example, the present invention can be applied to other semiconductor manufacturing apparatuses such as an etching and sputtering apparatus. Further, in this embodiment, the type of the valve is not limited, but when measuring dust in the exhaust system of the manufacturing apparatus, the valve does not have a sharp bending portion or a narrowing portion. It is better to use a ball valve or the like.

[0032]

According to the present invention, measurement of dust generated in a low-pressure container such as a CVD apparatus in an exhaust system is performed continuously over a long period of time except for a fixed time of pipe switching and purging. This makes it possible to suppress a decrease in device operating rate due to dust measurement.

Since the exhaust pipes have the same structure, the conductance and the like of the exhaust pipes do not change. Therefore, by exchanging the exhaust system pipes, the CVD reaction container 1
Since the container pressure does not change and the process of transporting dust from the CVD reaction container 1 to the dust monitor does not change, the influence on the measurement due to switching of the dust monitor is eliminated.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an exhaust system pipe according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an exhaust system pipe according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing the configuration of an exhaust system pipe according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an exhaust system pipe of a conventional example.

[Explanation of symbols]

1 ... CVD reaction container, 2 ... Gas supply pipe, 3 ... Wafer, 4
... vacuum pump, 5 ... valve, 6 ... valve.

Claims (1)

[Claims] 1. A reaction container, a gas supply system for introducing a gas into the reaction container, a gas exhaust system for exhausting the gas, a heating / cooling mechanism for a wafer, and a plasma source, which are installed in the reaction container. In a gas exhaust pipe of a semiconductor manufacturing apparatus for performing film formation or etching on the wafer, a part of the gas exhaust pipe has a plurality of systems, and a sensor for a particle monitor is attached in the middle of the pipes. Exhaust pipe for semiconductor manufacturing equipment.