JPH11271809A - Dry etching apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the clogging by the waste gaseous material in a waste gas treating section 24 by a solid collecting section and to prevent the outflow of volatile components from the solid collecting section when a treating section bypass stop valve of the waste gas treating section opens. SOLUTION: The solid collecting section 23 and the waste gas treating section 24 are successively arranged in a discharge line 22 of a dry etching section 21. A collecting section bypass line 44 having a collecting section bypass stop valve 45 is connected in parallel with the solid collecting section 23. A treating section bypass line 54 having the treating section bypass stop valve 55 is connected in parallel with the waste gas treating section 34. An inlet side stop valve 41 and an outlet side stop valve 42 are arranged in the inlet and outlet of the solid collecting section 23. A control section 46, which closes the inlet side stop valve 41 and the outlet side stop valve 42 when the treating section bypass stop valve 55 opens, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dry etching apparatus in a thin film transistor manufacturing process.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices have been widely used as display devices for information equipment.
In many cases, the liquid crystal display device is configured by arranging switching elements in pixel portions arranged in a matrix and connecting driving elements to the switching elements. Is often used.

In the process of forming a thin film transistor, S
In processing the i-film and the MoW film of the gate line, a dry etching process is generally performed from the viewpoint of excellent controllability of the taper shape and the processing accuracy of the line width. In a dry etching process, a source gas is excited by plasma in a decompressed processing chamber, and an etching target film is etched by active radical components and ions.

An unreacted gas remaining in the processing chamber and a reaction compound with the film to be etched are exhausted from the processing chamber by a vacuum pump. Since some of such exhaust gases have a high possibility of affecting the environment, they are discharged into an exhaust duct in a factory after being detoxified. As a device for detoxifying harmful exhaust gas, an exhaust gas treatment device using a neutralization reaction or an oxidation reaction is generally used.

FIG. 2 shows a configuration of a dry etching apparatus to which a general exhaust gas processing apparatus is added. A raw material gas is supplied from a gas supply unit 3 to a processing chamber 2 of a dry etching unit (hereinafter referred to as an etcher) 1 to perform etching. The exhaust gas containing the unreacted gas remaining in the processing chamber 2 and the reaction compound with the film to be etched is supplied to the vacuum pump 4.
The exhaust gas is exhausted to the exhaust line 5, flows into a column (not shown) in the exhaust gas processing unit 6 arranged in the middle of the exhaust line 5, reacts with the chemicals in the column and is rendered harmless, and then is exhausted in the factory. It is discharged to 7.

[0006]

However, Etcher 1
In the reaction gas with the film to be etched exhausted from
May contain substances with low vapor pressure. When the exhaust gas returns to room temperature in the piping of the exhaust line 5, it will be deposited as solids in the piping of the exhaust line 5 and in the column. When clogged in the piping, it can be cleaned regularly to remove the clog, but when clogged in the column, it cannot be cleaned, so despite the detoxification capacity still remaining, I have to change it. The exchange and refilling of the drug in the column incurs considerable costs, which leads to an increase in running costs.

Therefore, in order to solve such a problem, as shown in FIG. 3, a solid material is collected in an exhaust line 5 between a vacuum pump 4 of an etcher 1 and an exhaust gas processing section 6. It was considered to provide the solids collecting unit 8. Exhaust gas exhausted from the vacuum pump 4 is passed through a collection cartridge (not shown) provided in the solid matter collection unit 8. The inside of the collection cartridge is cooled, and the substances contained in the exhaust gas are forcibly changed to a solid state and accumulated in the collection cartridge. Therefore, clogging of the column in the exhaust gas processing unit 6 can be prevented. Furthermore, if the solid matter in the collection cartridge is taken out, it can be used many times, and the running cost can be kept low. In addition, if collection is insufficient with cooling alone, you can attach an inexpensive filter,
Even in this case, the running cost can be kept low. Therefore, the solid matter collecting unit 8 can eliminate clogging of the column and use the detoxifying processing capacity of the column to the end.

Usually, in the exhaust gas processing section 6, the exhaust line 5 is connected to a column system in order to prevent the internal pressure of the exhaust line 5 from becoming abnormally high when the column or the exhaust duct 7 in the factory is clogged. Generally, a bypass line 9 is provided separately. In other words, if the pressure monitor 10 is installed at the inlet of the column and the pressure exceeds the set value,
A mechanism is provided for automatically opening the bypass on-off valve 11 attached to the bypass line 9 and allowing exhaust gas to escape before the inside of the pipe becomes high pressure.

Therefore, when the bypass on-off valve 11 of the exhaust gas processing section 6 is opened, the exhaust gas from the etcher 1 does not pass through the column in the exhaust gas processing section 6, so that harmful exhaust gas passes through the bypass line. 9 flows into the exhaust duct 7 in the factory. Therefore, when the bypass on-off valve 11 of the exhaust gas processing unit 6 is opened, the etcher 1
By stopping the supply of the raw material gas from the gas supply unit 3, it is possible to prevent the raw material gas from flowing into the exhaust duct 7 in the factory.

However, in the dry etching apparatus to which the above-mentioned solid matter collecting section 8 is attached, the exhaust gas processing section 6
Even when the supply of the source gas of the etcher 1 is stopped when the bypass on-off valve 11 is opened, harmful volatile components from the solids accumulated in the solids collecting section 8 are sucked by the exhaust duct 7 in the factory. May be spilled. Therefore, it is necessary to rely on an exhaust gas treatment device installed on the exhaust duct 7 side in the factory.

The present invention has been made in view of the above points, and prevents clogging of an exhaust gas processing section with exhaust gas substances by adding a solid matter collecting section. It is an object of the present invention to provide a dry etching apparatus that can prevent a volatile component from flowing out of a solid matter collecting section when opened.

[0012]

According to the present invention, there is provided a dry etching apparatus comprising: a dry etching section; an exhaust line connected to the dry etching section; a solid collecting section disposed in the exhaust line; A collecting unit bypass line having a collecting unit bypass on-off valve connected to the exhaust line in parallel with the collecting unit, and between a junction where an outlet of the solids collecting unit and an outlet of the collecting unit bypass line join the exhaust line. An outlet-side on-off valve to be disposed, and a control unit for closing the outlet-side on-off valve when the collection unit bypass on-off valve is opened. Collect exhaust gas substances that materialize, and
By closing the outlet-side on-off valve of the solid matter collecting part when opening the collecting part bypass on-off valve, the outflow of volatile components from the solid matter collecting part can be prevented.

[0013] Also, a dry etching section, an exhaust line connected to the dry etching section, a solids collecting section arranged in the exhaust line, and a collecting section connected to the exhaust line in parallel with the solids collecting section. A collecting part bypass line having a part bypass opening / closing valve, an outlet side opening / closing valve disposed between an outlet of the solid matter collecting part and a junction where an outlet of the collecting part bypass line joins an exhaust line, and the exhaust line An exhaust gas processing unit disposed downstream of the solid matter collection unit, a processing unit bypass line having a processing unit bypass opening / closing valve connected to an exhaust line in parallel with the exhaust gas processing unit, and a processing unit bypass opening / closing unit. When the valve is opened, the control unit that closes the outlet-side on-off valve,
The solid matter collection unit prevents clogging of the exhaust gas treatment unit with exhaust gas substances, and further closes the outlet side on-off valve of the solid matter collection unit when the processing unit bypass on-off valve of the exhaust gas treatment unit opens. Thus, outflow of volatile components from the solids collecting section can be prevented.

Further, an inlet-side opening / closing valve is provided between the inlet of the solids collecting section and the branch point of the exhaust line connected to the inlet of the collecting section bypass line, and the control section opens the processing section bypass opening / closing valve. At that time, the inlet side on-off valve is closed,
The outflow of volatile components from the solids collecting section can be more reliably prevented.

Further, the control unit opens the collecting unit bypass on-off valve when the inlet-side on-off valve is closed, so that the exhaust line can be kept in a flowing state.

Further, the dry etching section has a gas supply section for supplying the source gas and stopping the supply of the source gas when the processing section bypass on-off valve is closed.
It is possible to prevent material gas from flowing out of the exhaust line.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a configuration diagram of a dry etching apparatus.

The dry etching apparatus has a dry etching section (hereinafter referred to as an etcher) 21, and a solids collecting section 23 and an exhaust gas processing section 24 are arranged in series in an exhaust line 22 of the etcher 21. The end of the exhaust line 22 is connected to an exhaust duct 25 in the factory.

The etcher 21 has a processing chamber 31 for performing an etching process. The processing chamber 31 is connected to a gas supply unit 32 for supplying a raw material gas, and has an unreacted reaction remaining in the processing chamber 31. Vacuum pump that sucks and exhausts exhaust gas such as gas and reaction compounds with the film to be etched to the exhaust line 22
33 is connected. The gas supply unit 32 has a function of receiving a signal from a control unit 56 of the exhaust gas processing unit 24, which will be described later, and stopping the supply of the source gas.

The exhaust line 22 is composed of a pipe connecting the etcher 21, the solids collecting section 23, the exhaust gas processing section 24, and the exhaust duct 25.

The solids collecting section 23 has a replaceable collecting cartridge (not shown) which is exchangeable. The inside of the collecting cartridge is cooled by cooling water or the like, and the exhaust gas flowing through the exhaust line 22 is cooled. , Solidifies and deposits on the bottom of the collection cartridge. Further, by attaching a filter (not shown) near the outlet of the collection cartridge, it is possible to prevent solid matter from flowing out to the latter stage of the collection cartridge.

An inlet-side opening / closing valve 41 and an outlet, which are constituted by a motor-operated valve such as a solenoid valve, which automatically opens and closes in response to a signal, are connected to the piping of the exhaust line 22 on the inlet side and the outlet side of the solid matter collecting section 23. Side opening / closing valves 42 are provided, respectively. That is, the inlet-side on-off valve 41 is disposed between the inlet of the solids collecting unit 23 and the branch point of the exhaust line 22 to which the inlet of the collecting unit bypass line 44 described later is connected. The outlet-side on-off valve 42 is disposed between the outlet of the solids collecting unit 23 and the junction where the outlet of the collecting unit bypass line 44 joins the exhaust line 22.

In the pipe of the exhaust line 22 upstream of the inlet-side on-off valve 41, a solids collecting section 23 and a pressure detecting section 43 for detecting the pressure in the pipe of the exhaust line 22 are provided.

A collecting section bypass line 44 is connected in parallel with the pressure detecting section 43, the inlet side opening / closing valve 41, the solid matter collecting section 23, and the outlet side opening / closing valve 42. This collection unit bypass line
The collection unit bypass opening / closing valve 45, which is configured by a motor-operated valve such as a solenoid valve that automatically opens and closes in response to a signal, is provided at 44.

The inlet-side on-off valve 41 in the solid matter collecting section 23,
The outlet side opening / closing valve 42, the collection unit bypass opening / closing valve 45, and the pressure detection unit 43 are connected to the control unit 46. This control unit 46
Is clogged inside the collection cartridge by the detection of the pressure detection unit 43, and the exhaust line at the later stage of the collection cartridge
When the pressure in the collection cartridge and piping due to clogging of 22 rises above the set value, the collection section bypass on-off valve
It has a function of automatically opening 45, and further receives a signal from a later-described control unit 56 of the exhaust gas processing unit 24, and
It has a function of automatically closing the 41 and the outlet-side on-off valve 42.

When the power is turned off, the inlet-side on-off valve 41 and the outlet-side on-off valve 42 are closed, and the collecting unit bypass on-off valve 45 is opened.

The exhaust gas processing section 24 has a replaceable column (not shown) which contains a chemical for reacting with the exhaust gas and rendering it harmless.

An inlet-side opening / closing valve constituted by a motor-operated valve such as a solenoid valve or a manual valve which automatically opens and closes in response to a signal in the piping of the exhaust line 22 on the inlet and outlet sides of the exhaust gas processing section 24. 51 and an outlet-side on-off valve 52 are provided, respectively. The exhaust gas processing unit 24 and the exhaust line 22 are connected to the piping of the exhaust line 22 upstream of the inlet-side on-off valve 51.
A pressure detection unit 53 for detecting the pressure in the piping is provided.

A processing section bypass line 54 is connected in parallel with the pressure detecting section 53, the inlet side opening / closing valve 51, the exhaust gas processing section 24 and the outlet side opening / closing valve 52. The processing unit bypass line 54 is provided with a processing unit bypass opening / closing valve 55 that is configured by an electric valve such as a solenoid valve that automatically opens and closes in response to a signal.

The processing section bypass on-off valve 55 and the pressure detection section 53 in the exhaust gas processing section 24, and the inlet side on-off valve 51 and the outlet side on-off valve 52 in the case of a motor-operated valve are connected to the control section 56. The control unit 56 detects the clogging inside the column and the clogging of the exhaust line 22 at the subsequent stage of the column by the detection of the pressure detection unit 53, and when the pressure in the column and the piping increases to a set value or more, the processing unit It has a function of automatically opening the bypass on-off valve 55.

When the power is turned off, the processing section bypass on-off valve 55 is configured to open.

During a normal dry etching process, the collecting section bypass on-off valve 45 and the processing section bypass on-off valve 55 are closed, and the inlet-side on-off valves 41, 51 and the outlet-side on-off valves 42, 52 are opened.

Therefore, by the operation of the vacuum pump 33, the exhaust gas such as the unreacted gas remaining in the processing chamber 31 and the reaction compound with the film to be etched is sucked and exhausted to the exhaust line 22, and the solid matter collecting section 23 and The exhaust gas is exhausted to the exhaust duct 25 in the factory through the exhaust gas processing unit 24. When the exhaust gas passes through the solids collecting section 23, the substance contained in the exhaust gas is cooled and forcibly becomes a solid state, and is deposited in the collection cartridge. When the exhaust gas passes through the exhaust gas processing unit 24,
Reacts with the drug in the column to render it harmless.

The processing section bypass on-off valve 55 is closed during normal dry etching processing, but is automatically opened during the next operation. That is, when the input pressure of the column of the exhaust gas processing unit 24 is increased by the pressure detection unit 53, when the power of the exhaust gas processing unit 24 is turned off, and when the column of the exhaust gas processing unit 24 is replaced. .

An increase in the input pressure of the column of the exhaust gas processing section 24 will be described. The cause of the input pressure rise is
If the inside of the column is clogged, if the exhaust capacity of the exhaust duct 25 in the factory where the column is connected is extremely reduced, if the flow rate of exhaust gas flowing into the column is abnormally high, 52 may be closed due to human error. In any of these cases, the pressure in the column or the piping of the exhaust line 22 increases,
When the value detected by the pressure detection unit 53 becomes equal to or greater than the set value, the processing unit bypass on-off valve 55 is automatically opened under the control of the control unit 56.

The case where the power of the exhaust gas processing unit 24 is turned off will be described. When the power is turned off, there is a stop of the power supply due to a power failure or the like, or a human error in operation. When the power of the exhaust gas processing unit 24 is turned off, the pressure monitoring by the pressure detection unit 53 does not work. Therefore, when the power is turned off, the pressure is automatically opened by the structure of the processing unit bypass on-off valve 55 itself.

The replacement of the column of the exhaust gas processing section 24 will be described. If the capacity of the drug in the column is reduced and the harmful substances in the exhaust gas cannot be detoxified, the replacement of the drug is required. To do so, the currently used column must be removed and replaced with a new one. At the time of replacing the column, the etching process cannot be performed, but it is desirable to keep the exhaust vacuum pump 33 and the like in operation in view of the operation rate of the unit. Therefore, the etcher
Since the exhaust line 22 capable of exhausting the air exhausted from the air 21 and the nitrogen for dilution which is always flown into the vacuum pump 33 is required, the processing unit bypass on-off valve 55 is opened. When the column is replaced, the inlet-side on-off valve 51 and the outlet-side on-off valve 52 are closed.

When the processing section bypass on-off valve 55 of the exhaust gas processing section 24 is opened, the control section of the exhaust gas processing section 24
From 56 to the gas supply unit 32 and the solid matter collection unit of the etcher 21
A signal is transmitted to the control unit 46 of the 23, and the following operations are automatically performed. That is, the source gas supplied from the gas supply unit 32 to the processing chamber 31 of the etcher 21 is automatically stopped, the collection unit bypass opening / closing valve 45 of the solid matter collection unit 23 is automatically opened, and the inlet side opening / closing valve 41 is opened. And the outlet side on-off valve 42 is automatically closed.

As a result, the exhaust line 22 leading from the etcher 21 to the exhaust duct 25 in the factory is secured through the collecting unit bypass line 44 and the processing unit bypass line 54 and the like. Department
It is possible to automatically prevent harmful volatile components from the solid matter accumulated in 23 from flowing out to the exhaust duct 25 in the factory.

That is, as in the conventional dry etching apparatus, when the processing section bypass on-off valve 55 of the exhaust gas processing section 24 is opened, the raw material gas from the etcher 21 and the solid matter accumulated in the solid matter collecting section 23 are removed. Harmful volatile components can be prevented from flowing out to the exhaust duct 25 in the factory through the processing unit bypass line 54.

As described above, by arranging the solid matter collecting unit 23 between the etcher 21 and the exhaust gas processing unit 24, it is possible to prevent the exhaust gas processing unit 24 from being clogged with the exhaust gas substance. When the processing unit bypass on-off valve 55 of the exhaust gas processing unit 24 is opened, by closing at least the outlet side on-off valve 42 of the solids collecting unit 23, it is possible to prevent the outflow of volatile components from the solids collecting unit 23. Can be.

Further, when the processing section bypass on-off valve 55 of the exhaust gas processing section 24 is opened, the inlet side on-off valve of the solids collecting section 23 is opened.
By simultaneously closing 41 as well, it is possible to more reliably prevent the outflow of volatile components from the solids collecting section 23.

[0044]

According to the dry etching apparatus of the present invention, the solid matter collecting section can collect the exhaust gas substance which solidifies in the exhaust gas, and collect the solid matter when opening the collecting section bypass on-off valve. By closing the outlet side on-off valve of the section, it is possible to prevent outflow of volatile components from the solid matter collecting section.

Further, by arranging the solid matter collecting section between the dry etching section and the exhaust gas processing section, clogging of the exhaust gas processing section with exhaust gas substances can be prevented,
Moreover, when the processing unit bypass on-off valve of the exhaust gas processing unit is opened, by closing the outlet-side on-off valve of the solid matter collecting unit,
It is possible to prevent the outflow of volatile components from the solids collecting section.

Further, when the processing section bypass on-off valve of the exhaust gas processing section is opened, the inlet side on-off valve of the solid matter collecting section is also closed, so that the outflow of volatile components from the solid matter collecting section is more reliably prevented. be able to.

Further, when the inlet-side on-off valve is closed, the exhaust line can be kept in a flowing state by opening the collecting section bypass on-off valve.

Further, when the processing section bypass on-off valve of the exhaust gas processing section is closed, the supply of the source gas from the gas supply section is stopped, so that the flow of the source gas from the exhaust line can be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a dry etching apparatus showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional dry etching apparatus.

FIG. 3 is a configuration diagram of another conventional dry etching apparatus.

[Explanation of symbols]

 21 Dry etching unit 22 Exhaust line 23 Solids collecting unit 24 Exhaust gas processing unit 32 Gas supply unit 41 Inlet side on-off valve 42 Outlet side on-off valve 44 Collection unit bypass line 45 Collection unit bypass on-off valve 46 Control unit 54 Processing unit bypass line 55 Processing section bypass on-off valve 56 Control section

Claims (5)

[Claims] 1. A dry etching section, an exhaust line connected to the dry etching section, a solids collecting section arranged in the exhaust line, and a collecting section connected to the exhaust line in parallel with the solids collecting section. A collecting part bypass line having a part bypass opening / closing valve, an outlet side opening / closing valve disposed between an outlet of the solid matter collecting part and a junction where an outlet of the collecting part bypass line joins an exhaust line, A dry-etching apparatus comprising: a control unit that closes the outlet-side on-off valve when the bypass on-off valve is opened. 2. A dry etching section, an exhaust line connected to the dry etching section, a solid collecting section arranged on the exhaust line, and a collecting section connected to the exhaust line in parallel with the solid collecting section. A collecting part bypass line having a part bypass opening / closing valve; an outlet side opening / closing valve disposed between an outlet of the solid matter collecting part and a junction where an outlet of the collecting part bypass line joins an exhaust line; An exhaust gas processing unit disposed downstream of the solid matter collecting unit; a processing unit bypass line having a processing unit bypass opening / closing valve connected to an exhaust line in parallel with the exhaust gas processing unit; A control unit for closing the outlet-side on-off valve when the valve is opened. 3. An on-off valve disposed between an inlet of the solids collecting unit and a branch point of an exhaust line to which an inlet of a collecting unit bypass line is connected, wherein the control unit includes a processing unit bypass open / close valve. 3. The dry etching apparatus according to claim 2, wherein the inlet-side on-off valve is closed when the valve is opened. 4. The control unit, when the inlet-side on-off valve closes,
4. The dry etching apparatus according to claim 2, wherein the collection section bypass on-off valve is opened. 5. The dry etching section has a gas supply section for supplying a source gas and stopping the supply of the source gas when the processing section bypass on-off valve is closed. Dry etching apparatus according to the above.