JP2001214888A - Vacuum exhaust device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a Pirani gauge from being damaged by a corrosive gas in a reaction chamber while having a function of protecting a turbo pump in a vacuum exhaust device. SOLUTION: A gas stop valve 2 for introducing an introduced gas into a reaction chamber 1, a Pirani gauge 6 provided with a Pirani isolation valve 19 between the reaction chamber 1, and a manometer gauge 1 provided with a manometer isolation valve 9.
0 and a configuration having a turbo pump 4 provided with a main valve 7, when introducing the introduced gas into the reaction chamber 1, close the Pirani isolation valve 19 to prevent the Pirani gauge 6 from being exposed to the introduced gas. Then, when it is determined that the pressure needs to be detected by the manometer gauge 10 and further detected by the Pirani gauge 6, the Pirani isolation valve 19 is opened, the pressure is measured by the Pirani gauge 6, and the pressure of the turbo pump 4 is measured. Determine the need for protection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor wafer,
The present invention relates to an evacuation apparatus and a method used for manufacturing a liquid crystal substrate or the like.

[0002]

2. Description of the Related Art Conventionally, as an example of a vacuum evacuation apparatus, a dry etching apparatus for producing a semiconductor wafer, a liquid crystal substrate and the like has been known. FIG. 4 is a view showing an exhaust system of a conventional dry etching apparatus. In FIG. 4, reference numeral 1 denotes a reaction chamber where a reaction gas is introduced from a gas stop valve 2 to process a substrate or the like. In the following, the dry pump 3 and the turbo pump 4 are started up. Then, the bypass valve 5 is opened to evacuate the dry pump 3. Next, when a predetermined switching vacuum degree is detected by the Pirani gauge 6, the main valve 7 and the foreline valve 8 are opened to switch to vacuuming by the turbo pump 4. Then, the manometer isolation valve 9 is opened, and the
Start the measurement of the degree of vacuum with the analog value through the D converter. Next, by opening the gas stop valve 2, a reaction gas is introduced into the reaction chamber 1 to start the etching process.

As a semiconductor manufacturing apparatus for preventing corrosion and destruction of a Pirani gauge, one disclosed in Japanese Patent Application Laid-Open No. 10-7008 is disclosed (FIG. 5).

In FIG. 5, a gate valve 1 is provided in a reaction chamber 1.
The wafer is carried in from 1, and a reaction gas is introduced into the reaction chamber 1 from the gas introduction pipes 13 and 14 while the wafer is heated by the heater 12, and exhausted from the exhaust pipes 15 and 16 to form a film on the wafer. If a corrosive gas is used as the reaction gas at this time, the Pirani gauge 6 is exposed to the corrosive gas when the corrosive gas is exhausted.
7 to which the protection valve 18 and the Pirani gauge 6 are connected.
Are connected in this order. Then, the protection valve 18 is closed to prevent the corrosive gas from flowing toward the Pirani gauge 6.

[0005]

However, in the apparatus shown in FIG. 4, depending on the gas used, the Pirani gauge breaks down in about one week, and the apparatus becomes unusable. Has to be replaced, which is costly and time-consuming.

In the apparatus shown in FIG. 5, the pressure in the reaction chamber is adjusted by a pressure control valve at the latter stage of the reaction chamber, and a vacuum exhaust apparatus for performing processing while exhausting corrosive gas, for example, an etching apparatus is used during processing. The Pirani gauge cannot be used. On the other hand, in a device having a normal turbo pump, when the pressure in the preceding stage of the turbo pump is constantly increased, it is necessary to close the main valve from the viewpoint of protection of the turbo pump so that the pressure is not applied to the turbo pump. However, a Pirani gauge had to be used for the detection, and no protection valve was used.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a vacuum evacuation apparatus and method for preventing a Pirani gauge from being damaged while having a function of protecting a turbo pump.

[0008]

In order to solve this problem, the present invention provides a gas stop valve for introducing an introduction gas into a reaction chamber, a Pirani gauge provided with a Pirani isolation valve between the reaction chamber, It has a manometer gauge provided with a manometer isolation valve between the reaction chamber and a turbo pump provided with a main valve between the reaction chamber.

With this configuration, when introducing the introduced gas into the reaction chamber, the Pirani isolation valve can be closed to prevent the Pirani gauge from being exposed to the introduced gas. In addition, if it is determined that the pressure needs to be detected with a manometer gauge and further detected with a Pirani gauge, the Pirani isolation valve is opened, the pressure is measured with a Pirani gauge, and the necessity of turbo pump protection is determined. Can be.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows a first embodiment of a vacuum evacuation apparatus according to the present invention, and specifically shows an evacuation system of a dry etching apparatus. In FIG. 1, a reaction chamber 1
Is a place where a reaction gas is introduced from the gas stop valve 2 to process a substrate or the like (not shown). The turbo pump 4 is connected to the reaction chamber 1 via a main valve 7, and the dry pump 3 is connected to the turbo pump 4 via a foreline valve 8 and the reaction chamber 1 via a bypass valve 5. It is connected to the. The Pirani gauge 6 is connected to the reaction chamber 1 via a Pirani isolation valve 19, and the manometer gauge 10 is connected to the reaction chamber 1 via a manometer isolation valve 9.

FIG. 2 is a block diagram showing an etching method according to the first embodiment of the present invention.
In the control unit 20, the gas stop valve 2, the bypass valve 5, the main valve 7, the foreline valve 8, the manometer isolation valve 9, and the pressure detected by the Pirani gauge 6 and the manometer gauge 10 are used.
It functions to switch the Pirani isolation valve 19.

FIG. 3 shows the flow of the etching method according to the first embodiment of the present invention. First, in step S1, the power is turned on, and in step S2, the dry pump 3 and the turbo pump 4 are started up.
In step S3, the bypass valve 5 is opened to evacuate the air by the dry pump 3, and the Pirani isolation valve 19 is opened to detect the pressure in the reaction chamber by the Pirani gauge 6. And in step S4,
Judge whether the specified switching pressure has been reached,
If it has reached, in step S5, the main valve 7
The foreline valve 8 is opened to switch to vacuuming by the turbo pump 4, the manometer isolation valve 9 is opened, and the measurement of the degree of vacuum is started with the analog value through the AD converter using the manometer gauge 10. Next, in step S6, the reaction gas is introduced into the reaction chamber 1 by opening the gas stop valve 2, and the Pirani isolation valve 19 is closed to protect the Pirani gauge 6 from the reaction gas. And
In step S7, the reaction chamber 1 is
It is determined whether or not the pressure is equal to or lower than a predetermined value. If the pressure is equal to or lower than the predetermined value, it is determined in step S8 whether or not the etching is completed. If not, the process returns to step S7 and ends. If so, the Pirani isolation valve 19 is opened in the step S9, and a series of flows is ended. If it is larger than the predetermined value in step S7, the Pirani isolation valve 19 is opened in step S10, and in the next step S11, the pressure of the reaction chamber 1 is set to the predetermined switching pressure by the Pirani gauge 6. It is determined whether the value is equal to or less than a predetermined value.
In step, the Pirani isolation valve 19 is closed and the process returns to step S7.
In step S13, the main valve 7 and the foreline valve 8 are closed, and the process ends.

Therefore, according to the above configuration, when introducing the reaction gas into the reaction chamber, the Pirani isolation valve can be closed to prevent the Pirani gauge from being exposed to the reaction gas, and the pressure can be detected by the manometer gauge. Then, if it is determined that there is a need to detect with a Pirani gauge, the Pirani isolation valve is opened, the pressure is measured with the Pirani gauge, and the necessity of turbo pump protection can be determined.

In the above embodiment, the reaction gas is introduced into the reaction chamber. However, the reaction gas may be introduced instead of the reaction gas.

[0016]

As described above, according to the present invention, a gas stop valve for introducing an introduced gas into a reaction chamber, a Pirani gauge provided with a Pirani isolation valve between the reaction chamber, By introducing a manometer gauge provided with a manometer isolation valve in between, and a turbo pump provided with a main valve between the reaction chamber, when introducing the introduced gas into the reaction chamber, Pirani isolation The valve can be closed to prevent the Pirani gauge from being exposed to the introduced gas, and if the pressure is detected by the manometer gauge and it is determined that the Pirani gauge needs to be detected, the Pirani isolation valve is used. Open and measure the pressure with a Pirani gauge to determine the need for turbo pump protection Interest effect can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a block diagram of an etching method according to the first embodiment of the present invention;

FIG. 3 is a diagram showing a flow of an etching method according to the first embodiment of the present invention;

FIG. 4 is a diagram showing a configuration of an exhaust system of a conventional etching apparatus.

FIG. 5 is a diagram showing a configuration of a conventional semiconductor manufacturing apparatus for preventing corrosion and destruction of a Pirani gauge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction chamber 2 Gas stop valve 4 Turbo pump 6 Pirani gauge 7 Main valve 9 Manometer isolation valve 10 Manometer gauge 19 Pirani isolation valve

Continued on the front page F-term (reference) 3H031 DA00 DA01 DA02 EA09 EA15 FA00 FA37 FA38 3H076 AA21 BB28 BB43 BB45 CC41 CC51 CC91 CC94 CC98

Claims (2)

[Claims] 1. A gas stop valve for introducing an introduction gas into a reaction chamber, a Pirani gauge provided with a Pirani isolation valve between the reaction chamber, and a manometer provided with a manometer isolation valve between the reaction chamber. An evacuation apparatus comprising a turbo pump provided with a main valve between a gauge and the reaction chamber. 2. A step of opening a Pirani isolation valve to detect a pressure in the reaction chamber with a Pirani gauge, a step of opening a manometer isolation valve and detecting a pressure of the reaction chamber with a manometer gauge, and a gas stop valve. Opening the introduced gas into the reaction chamber, closing the Pirani isolation valve, and opening the Pirani isolation valve when the pressure detected by the manometer gauge exceeds a predetermined value. Detecting the pressure with the Pirani gauge by using a Pirani gauge.