JPH07171374A - Method for operating exhaust valve - Google Patents

Abstract

PURPOSE:To enable the sure detection of the malfunction of a valve and to check a leakage from a reaction chamber even when throughleak is generated in the valve. CONSTITUTION:Three-way valves 3, 4 are arranged on both sides of an exhaust valve 1 both ends of which is connected to a reaction chamber 5 and an exhaust pump 6, a bypass line 2 is connected to the valve 1 in parallel by these three- way valves, and a pressure meter 7 is arranged between the reaction chamber 5 and the three way valve 3. If the indication of the pressure meter does not change even when the valve 1 is opened to reduce the pressure in the reaction chamber 5, the three-way valves 3, 4 are released to the bypass line side to reduce the pressure of the reaction chamber 5. The change in the indication of the pressure meter in this operation denotes the malfunction of the valve 1. If no change is found in the indication of the pressure meter 7, the pressure meter shows to be in a trouble. When the three-way valve 3 is shifted to the bypass line 2 side and the three-way valve 4 is shifted to the valve 1 side, a leakage from the reaction chamber 5 can be checked even when throughleak is generated in the valve 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating an exhaust system valve used in a semiconductor manufacturing apparatus having an exhaust system line.

[0002]

2. Description of the Related Art In recent years, a vacuum system has been used to improve film quality and uniformity during film formation in the manufacture of semiconductors. It is also used for dry etching and plasma generation for film formation by plasma. Also, from the viewpoint of safety, gas is exhausted by vacuum. The exhaust system valve is used to switch lines and prevent backflow of air and dust into the reaction chamber.

An example of a method for operating the above-mentioned conventional exhaust system valve will be described below with reference to the drawings.

FIG. 4 shows a conventional exhaust line. In FIG. 4, reference numeral 1 is a valve that can be opened and closed by electricity, high-pressure air, or the like. Reference numeral 5 is a reaction chamber in which a wafer is processed. 6 is an exhaust pump, and 7 is a reaction chamber 5.
It is a pressure gauge for measuring the internal pressure of. Reference numeral 8 is a controller for controlling the opening / closing of the valve 1.

Now, consider a case where the display of the pressure gauge 7 does not change when the valve 1 is opened to evacuate the reaction chamber 5. At this time, the controller 8 sends an open signal to the valve 1. However, for example, if the valve 1 malfunctions and the valve 1 does not open, the pressure in the reaction chamber 5 does not drop and the display of the pressure gauge 7 does not change. Even if the pressure gauge 7 is out of order, the display of the pressure gauge 7 does not change. As described above, it is not possible to externally determine whether the valve 1 is malfunctioning or the pressure gauge 7 is out of order.

When performing a leak check of the reaction chamber 5, first, the reaction chamber 5 is sufficiently evacuated. Then valve 1
Close. When the reaction chamber 5 is leaking and the valve 1 is normal, the pressure in the reaction chamber 5 gradually rises. This makes it possible to determine that the reaction chamber 5 is leaking.

[0007]

Now, let us consider a leak check of the reaction chamber 5 when the valve 1 has a through leak. At this time, even if the valve 1 is closed, the reaction chamber 5 is exhausted by the through leak. Even if the reaction chamber 5 is leaking, the pressure in the reaction chamber 5 does not rise due to exhaust by the through leak of the valve 1. That is, at the time of the leak check, the pressure inside the reaction chamber 5 does not rise, so it cannot be concluded that the reaction chamber 5 is not leaking.

The prior art has a problem that it is not possible to identify a malfunction of the valve 1 and a leak check cannot be performed completely.

In view of the above problems, the present invention provides a method for operating an exhaust system valve provided with a bypass line.

[0010]

In order to solve the above problems, an exhaust system line according to the present invention includes a valve, first and second three-way valves provided before and after the valve, and the first and second valves. A bypass line connected in parallel with the valve by a three-way valve is provided, and the first and second three-way valves are opened to the bypass line side, or the first three-way valve is connected to the bypass line side. In the second
The three-way valve is opened to the valve side.

[0011]

According to the present invention, with the above-described structure, the reaction chamber can be evacuated without passing through the valve, and by utilizing this, malfunction of the valve can be found.

Further, the position of the provided three-way valve enables the leak check of the reaction chamber to be surely performed even when the valve has a through leak.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the construction of an exhaust system line in an embodiment of the present invention. In FIG. 1, elements corresponding to those shown in FIG. 4 are designated by the same reference numerals.

In FIG. 1, reference numeral 1 is a valve of an exhaust system line. The valve 1 can be opened and closed by electricity or high pressure air. The valve 1 can be freely opened and closed by an electric signal from software for controlling the process. Reference numeral 2 is a bypass line provided in parallel with the valve 1. Reference numerals 3 and 4 are manual three-way valves for switching the valve 1 and the bypass line 2. 5 is a reaction chamber for carrying out processes such as film formation, and 6
Is an exhaust pump for exhausting the reaction chamber 5. One of the exhaust system lines is connected to the reaction chamber 5, and the other is connected to the exhaust pump 6. Reference numeral 7 is a pressure gauge for measuring the internal pressure of the reaction chamber 5. Reference numeral 8 is a controller for controlling the opening / closing of the valve 1. Bypass line 2 is valve 1
Three-way valves 3 and 4 are arranged in the front and rear pipes, and are provided in parallel with the valve 1. By providing the bypass line 2 in parallel with the valve 1, the exhaust pump 6 can be used to exhaust gas from the reaction chamber 5 without passing through the valve 1.

The operation method of the exhaust system line configured as described above will be described below with reference to FIGS. 1 and 2.

FIG. 2 shows a first embodiment of the method for operating an exhaust system line according to the present invention, and is a diagram showing the structure when both the three-way valves 3 and 4 are switched to the bypass line 2 side.

Now, consider the case where the display of the pressure gauge 7 does not change when the valve 1 is opened and the reaction chamber 5 is evacuated. At this time, the controller 8 sends an open signal to the valve 1. However, for example, if the valve 1 malfunctions and the valve 1 does not open, the pressure in the reaction chamber 5 does not drop and the display of the pressure gauge 7 does not change. Even if the pressure gauge 7 is out of order, the display of the pressure gauge 7 does not change. As described above, it is not possible to externally determine whether the valve 1 is malfunctioning or the pressure gauge 7 is out of order.

Therefore, the three-way valves 3 and 4 are set to the positions shown in FIG. 2, and the reaction chamber 5 is evacuated through the bypass line 2. In this case, the reaction chamber 5 can always be in a vacuum state. If the display of the pressure gauge 7 changes in this state, it is possible to conclude that the valve 1 is malfunctioning in consideration of the above result. If no pressure change is observed even in this state, it can be concluded that the pressure gauge 7 is out of order.

As described above, according to this embodiment, the reaction chamber 5 can be evacuated without passing through the valve 1, and the malfunction of the valve 1 can be found by utilizing this.

The operation of the second embodiment of the present invention will be described below with reference to FIGS. 1 and 3.

FIG. 3 shows a second embodiment of the method for operating the exhaust system valve according to the present invention. It is a figure which shows the structure when switching the three-way valve 3 to the bypass line 2 side and the three-way valve 4 to the valve 1 side.

When performing a leak check of the reaction chamber 5, first, the reaction chamber 5 is sufficiently evacuated. Then valve 1
Close. When the reaction chamber 5 is leaking and the valve 1 is normal, the pressure in the reaction chamber 5 gradually rises. This makes it possible to determine that the reaction chamber 5 is leaking.

Now, let us consider a leak check of the reaction chamber 5 when the valve 1 has a through leak. At this time, even if the valve 1 is closed, the reaction chamber 5 is exhausted by the through leak. Even if the reaction chamber 5 is leaking, the pressure in the reaction chamber 5 does not rise due to exhaust by the through leak of the valve 1. That is,
Since there is no pressure increase in the reaction chamber 5 during the leak check, it cannot be concluded that the reaction chamber 5 is not leaking.

Therefore, consider a case where the valves 3 and 4 are set to the positions shown in FIG. 3 to perform a leak check. The exhaust pump side is shut off by a three-way valve 3, and the reaction chamber side is shut off by a three-way valve 4. As a result, the exhaust system line is completely shut off. Even if the valve 1 has a through leak, the piping is blocked by the three-way valves 3 and 4, so that the leak check can be performed completely.

As described above, according to the present embodiment, the position of the three-way valve as shown in FIG. 3 makes it possible to reliably perform the leak check of the reaction chamber 5 even when the valve 1 has a through leak.

In the second embodiment, the three-way valve 3
Although the three-way valve 4 is on the bypass line side and the three-way valve 4 is on the valve 1 side, the same effect can be obtained by setting the three-way valve 4 on the bypass line side and the three-way valve 3 on the valve 1 side.

[0027]

As described above, according to the present invention, the reaction chamber can be evacuated without passing through the valve, and by utilizing this, the malfunction of the valve can be found. Further, the position of the provided three-way valve makes it possible to reliably perform a leak check of the reaction chamber even when the valve has a through leak.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an exhaust system line in first and second embodiments of the present invention.

FIG. 2 is a configuration diagram for explaining an operating method in the first embodiment of the present invention.

FIG. 3 is a configuration diagram for explaining an operating method in a second embodiment of the present invention.

FIG. 4 is a schematic diagram of a conventional exhaust system line.

[Explanation of symbols]

 1 Operation valve 2 Bypass line 3,4 Three-way valve 5 Reaction chamber 6 Exhaust pump 7 Pressure gauge 8 Controller

Claims (2)

[Claims] 1. A valve, first and second three-way valves provided before and after the valve, and a bypass line connected in parallel with the valve by the first and second three-way valves,
A method for operating an exhaust system valve, wherein the first and second three-way valves are opened to the bypass line side. 2. The method for operating an exhaust system valve according to claim 1, wherein the first three-way valve is opened to the bypass line side and the second three-way valve is opened to the valve side.