JP2000015047A - Exhaust gas detoxifying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent temperature rise in a reaction tube when exhaust gas inflow from a semiconductor manufacturing device stops, by making nitrogen flow in the reaction tube arbitrarily with a nitrogen introduction means for preventing the temperature rise in a reaction part. SOLUTION: When an exhaust gas switching valve in a semiconductor manufacturing device 1 is closed, a nitrogen introduction means 11 to open and close a passage of nitrogen, which flows in a nitrogen inflow pipe 12, for temperature rise prevention is opened to introduce the nitrogen for the temperature rise prevention flow into a reaction tube 7 continuously. The nitrogen for the temperature rise prevention, which flows in the reaction tube 7, mitigates rapid decrease in a flow rate of the total inflow gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas abatement system having an exhaust gas introduction section from a semiconductor manufacturing apparatus, a reaction section, and a heater for heating the reaction section, and detoxifying the exhaust gas by thermal decomposition.

[0002]

2. Description of the Related Art As one of exhaust gas abatement apparatuses for removing specific harmful substances contained in an exhaust gas from a semiconductor manufacturing apparatus and then reducing it to the atmosphere, an exhaust gas introducing section, a reaction section and the reaction section are used. An exhaust gas abatement apparatus having a heater for heating and performing oxidative decomposition treatment of the exhaust gas by thermal decomposition in the reaction section is known.

FIG. 4 is a schematic diagram showing the configuration of a conventional exhaust gas abatement apparatus.

The exhaust gas to be removed from the semiconductor manufacturing apparatus 1 passes through the opened exhaust gas switching valve 2 b of the exhaust gas removal apparatus, and the exhaust gas inflow pipe provided in the reaction tube 7 of the exhaust gas removal apparatus 10. 3, the air from the air inflow pipe 5 and the nitrogen from the nitrogen inflow pipe 4 together flow into and out of the reaction section 9 preheated by the heater 6,
After the thermal oxidative decomposition, the harmful gas components are released into the atmosphere via the exhaust unit 8 in a state where they are rendered harmless.

[0005] The air from the air inlet pipe 5 is supplied as an oxidizing source in the oxidative decomposition of exhaust gas, and the nitrogen from the nitrogen inlet pipe 4 is used to mix the exhaust gas with the air during the exhaust gas treatment. Inflow pipe 3 or reaction pipe 7
It is supplied for the purpose of preventing solid matter from adhering to the inner surface and rapid oxidation reaction, and purging the inside of the reaction section 9 when the exhaust gas cannot be processed.

[0006]

However, in the above-mentioned conventional exhaust gas abatement apparatus, the state in which the inflow of exhaust gas from the semiconductor manufacturing apparatus is stopped despite the fact that the exhaust gas abatement apparatus is in a state capable of treating the exhaust gas. (For example, in a state where the exhaust line of the semiconductor manufacturing apparatus is switched to another line), the temperature of the reaction section cannot be controlled due to a decrease in the flow rate of the total inflow gas into the exhaust gas abatement apparatus, and the exhaust gas abatement apparatus Causes a rapid rise in temperature inside the reaction tube. This rapid temperature rise causes abnormalities and deterioration of the reaction tube or the heater of the exhaust gas abatement system, and the stable operation of the exhaust gas abatement system and the semiconductor manufacturing equipment connected to the exhaust gas abatement system. Had the problem of hindering.

Accordingly, the present invention has been made in view of such a problem,
Means for preventing temperature rise in the reaction section of the exhaust gas abatement system;
An object of the present invention is to provide an exhaust gas abatement apparatus having the temperature rise prevention means.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, an exhaust gas abatement apparatus of the present invention is characterized by having a means for introducing nitrogen into a reaction section for preventing a rise in temperature.

[0009] The present invention is characterized in that a nitrogen flow control means for preventing temperature rise is provided.

Further, the present invention is characterized in that it has an opening / closing operation control function of the temperature rise preventing nitrogen introducing means for synchronizing the temperature rise preventing nitrogen introducing means when the flow of exhaust gas from the semiconductor manufacturing apparatus is stopped.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a configuration of an exhaust gas abatement apparatus according to the first aspect of the present invention.

The exhaust gas abatement apparatus 10 of the present invention has an exhaust gas introducing section 30, a reaction tube 7, a heater 6, a reaction section 9 heated by the heater 6, and an exhaust section 8.

The exhaust gas introducing section 30 is located above the reaction tube 7 and is located upstream of the semiconductor manufacturing apparatus 1 through the exhaust gas inflow pipe 3.
And an air inlet pipe 5 for supplying air as an oxygen source for oxidatively decomposing exhaust gas to be harmed.
And a nitrogen inflow pipe 4 as a nitrogen flow path for preventing solid matter from adhering to the exhaust gas inflow pipe 3 by mixing and oxidative decomposition of the exhaust gas and air and preventing a rapid oxidation reaction. . On the other hand, the nitrogen inflow pipe 12 is connected to the exhaust gas inflow pipe 3 as a nitrogen flow path for preventing temperature rise.

Reference numeral 11 denotes nitrogen introducing means for opening and closing the flow path of the nitrogen for preventing temperature rise flowing through the nitrogen inflow pipe 12, which can be arbitrarily opened and closed (for example, a solenoid valve).

Referring to FIG. 1, the operation of the exhaust gas abatement apparatus 10 when the exhaust gas can be treated will be described.

From the semiconductor manufacturing apparatus 1 to the exhaust gas abatement apparatus 10
Exhaust gas discharged into the reaction section 9 via the exhaust gas inflow pipe 3 provided in the exhaust gas introduction section 30 is supplied to the heater 6 together with the air from the air inflow pipe 5 and the nitrogen from the nitrogen inflow pipe 4. Is discharged into the reaction section 9 which has been heated in advance, and is released into the atmosphere via the exhaust section 8 in a state where harmful gas components are rendered harmless by thermal oxidative decomposition. The temperature of the heater 6 is controlled by a temperature detecting means 20 attached to the reaction section 9.
The temperature is controlled by the temperature control means 21 so that the temperature detected by the thermocouple (for example, a thermocouple) is constant. The temperature is controlled by the exhaust gas from the semiconductor manufacturing apparatus 1, the air from the air inlet pipe 5,
In the state where nitrogen from the nitrogen inflow pipe 4 is actually flowed, the state is set to have the highest removal efficiency in the reaction section 9.

However, in the conventional technique shown in FIG. 4, immediately after the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed, the amount of gas flowing into the reaction tube 7 via the exhaust gas inlet pipe 3 is zero. Become. Here, the gas flowing into the reaction tube 7 is only the air from the air inflow tube 5 and the nitrogen from the nitrogen inflow tube 4.
The total flow rate of gas flowing into the reaction tube 7 decreases by the amount of gas flowing into the inside.

As the total flow rate of the gas flowing into the reaction tube 7 decreases, the temperature of the reaction section 9 rises temporarily, and the temperature control means 2
Although 1 controls the temperature of the reaction section 9 by controlling the heater 6, the temperature of the reaction section 9 cannot follow the control, and the exhaust gas abatement apparatus 1 causes a sharp rise in the temperature inside the reaction tube 7. This situation becomes more remarkable as the amount of exhaust gas to be removed from the semiconductor manufacturing apparatus 1 increases, and this rapid temperature rise is caused by an abnormality in the reaction tube 7 or the heater 6 of the exhaust gas removal apparatus 10. This is a factor that causes deterioration, and has a problem of hindering stable operation of the exhaust gas abatement apparatus 10 and the semiconductor manufacturing apparatus 1 connected to the exhaust gas abatement apparatus 10.

Therefore, according to the exhaust gas abatement apparatus of the present embodiment, when the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed in FIG. Nitrogen introduction means 1 for opening and closing the road
By opening 1, nitrogen for preventing temperature rise continuously flows into the reaction tube 7. The nitrogen for preventing temperature rise that has flowed into the reaction tube 7 has an effect of alleviating a sudden decrease in the total flow rate of gas flowing into the reaction tube 7, and facilitates the follow-up control of the temperature of the reaction section 9, and Also, it is possible to prevent a rapid rise in the temperature inside the reaction tube 7 which may cause an abnormality or deterioration of the heater 6.

Further, a nitrogen flow rate control means which can arbitrarily set the temperature rise prevention nitrogen flow rate may be added. Examples will be described below.

FIG. 2 is a schematic diagram showing the configuration of a semiconductor gas abatement apparatus according to the second aspect of the present invention. In the exhaust gas abatement apparatus shown in FIG. A nitrogen flow control means 40 capable of arbitrarily setting the flow rate of nitrogen flowing through the nitrogen inflow pipe 12 as a path is added.

Regarding the operation when the exhaust gas can be treated,
The description is omitted because it is the same as in the first embodiment, and the operation when the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed will be described.

In FIG. 2, when the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed, the nitrogen introducing means 11 for opening and closing the temperature rise preventing nitrogen flow through the nitrogen inlet pipe 12 is opened. Accordingly, nitrogen for preventing temperature rise continuously flows into the reaction tube 7. Here, the flow rate of the temperature rise preventing nitrogen flowing into the reaction tube 7 through the nitrogen inflow pipe 12 is controlled by the nitrogen flow rate control means 40. At this time, the temperature control of the reaction section 9 is not hindered, and the flow rate optimal for the control is set in advance, thereby facilitating the temperature control of the reaction section 9, preventing the rapid temperature rise inside the reaction tube 7, This is more effective for reducing the temperature fluctuation in the pipe.

FIG. 3 is a schematic diagram showing a configuration of a semiconductor gas abatement apparatus according to the third aspect of the present invention. Opening / closing operation mechanism 41 for synchronizing the opening / closing of the nitrogen introduction means 11 for opening / closing the nitrogen flow path for use with the closing / opening of the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1. Is added.

When the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed, the opening / closing operation control mechanism 41
1 is opened, and the nitrogen introducing means 11 is controlled so that the nitrogen introducing means 11 is closed when the exhaust gas switching valve 2b is opened.

In FIG. 3, when the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed, in synchronism therewith, a nitrogen introducing means for opening and closing the temperature rise preventing nitrogen flow by the opening / closing operation control mechanism 41. 11 is opened, and nitrogen for preventing temperature rise continuously flows into the reaction tube 7 via the nitrogen inflow tube 12, so as to alleviate a decrease in the flow rate of the total inflow gas into the reaction tube 7. Conversely, when the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is opened, the nitrogen introducing means 1 is synchronized with the opening.
1 is closed, the flow of nitrogen for preventing temperature rise into the reaction tube 7 stops, and the exhaust gas from the semiconductor device 1 flows into the reaction tube 7.

With the addition of the opening / closing operation control mechanism 41, the exhaust gas is stopped at the same time as the exhaust gas switching valve 2b of the semiconductor manufacturing apparatus 1 is closed.
The semiconductor manufacturing apparatus 1
By controlling the flow of nitrogen for preventing temperature rise into the inside of the reaction tube 7 in response to the state change, the temperature rise and temperature fluctuation inside the reaction tube in response to the state of the semiconductor manufacturing apparatus 1 can be reduced.

[0029]

According to the first aspect of the present invention, when the inflow of exhaust gas from the semiconductor manufacturing apparatus is stopped, nitrogen can be arbitrarily introduced into the reaction tube by providing the nitrogen introduction means for preventing the temperature of the reaction section from rising. It is possible to prevent the temperature inside the pipe from rising.

According to a second aspect of the present invention, the flow rate of nitrogen flowing into the reaction tube can be arbitrarily set by the nitrogen introducing means for preventing temperature rise when the flow of exhaust gas from the semiconductor manufacturing apparatus is stopped. Temperature fluctuation can be reduced.

According to a third aspect of the present invention, there is provided an operation control function of the temperature rise preventing nitrogen introducing means for synchronizing the temperature rise preventing nitrogen introducing means according to the second aspect when the flow of exhaust gas from the semiconductor manufacturing apparatus is stopped. Thus, it is possible to reduce the temperature rise and the temperature fluctuation inside the reaction tube corresponding to the state of the semiconductor manufacturing apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the configuration of a semiconductor gas abatement apparatus according to the first embodiment.

FIG. 2 is a schematic diagram showing the configuration of a semiconductor gas abatement apparatus according to the second embodiment.

FIG. 3 is a schematic diagram showing a configuration of a semiconductor gas abatement apparatus according to the invention of claim 3;

FIG. 4 is a schematic diagram showing a configuration of a conventional gas abatement apparatus for semiconductors.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor manufacturing apparatus 2a, 2b Exhaust gas switching valve 3 Exhaust gas inflow pipe 4, 12 Nitrogen inflow pipe 5 Air inflow pipe 6 Heater 7 Reaction tube 8 Exhaust part 9 Reaction part 10 Exhaust gas removal device 11 Nitrogen introduction means 20 Temperature detection means 21 Temperature control means 30 Exhaust gas introduction part 40 Nitrogen flow rate control means 41 Opening / closing operation control means

Claims (3)

[Claims] 1. An exhaust gas abatement system comprising an exhaust gas introduction section from a semiconductor manufacturing apparatus, a reaction section, and a heater for heating the reaction section, wherein the exhaust gas detoxification apparatus detoxifies the exhaust gas by thermal decomposition. An exhaust gas abatement apparatus comprising a nitrogen introducing means for preventing temperature rise. 2. The exhaust gas abatement apparatus according to claim 1,
An exhaust gas abatement apparatus comprising a nitrogen flow control means for preventing temperature rise. 3. The exhaust gas abatement apparatus according to claim 2,
An exhaust gas abatement apparatus characterized by having an opening / closing operation control function of a temperature rise preventing nitrogen introducing means for synchronously operating a temperature rise preventing nitrogen introducing means when an inflow of exhaust gas from a semiconductor manufacturing apparatus is stopped.