TW201601819A - Low pressure plasma reactor for exhaust gas treatment - Google Patents

Abstract

The invention relates to a low pressure plasma reactor capable of processing an exhaust gas that contains a fluorine-based or chlorine-based gas in a processing chamber by minimizing etching of the internal surface of a dielectric caused by ion collision to continue processing the exhaust gas. The low pressure plasma reactor includes a magnetic field generator and a housing to form a dual chamber structure so as to achieve safe processing. Thus, an optimized magnetic field value is provided and applied for reducing the surface etching of the dielectric due to plasma ions. The housing not only physically seals the dielectric tube and a driving electrode and the magnetic field generator that circularly cover an outer surface thereof, but also blocks electromagnetic interference of the low pressure plasma reactor.

Description

Low pressure plasma reactor for waste gas treatment

The present invention relates to a plasma reactor, and more particularly to an electric charge for decomposing exhaust gas containing unreacted process gas (gas), purge gas, or a portion of initial reactants discharged in a low pressure process. A slurry reactor, particularly a low pressure plasma reactor which solves the problem of erosion of the inner surface of the reactor when the exhaust gas (including a fluorine-based or chlorine-based gas) becomes severe.

In processes such as semiconductors, display devices, and solar cells, processes such as functional film formation and dry etching are applied. Such a process is usually implemented in a vacuum chamber in which a plurality of metal and non-metal precursors are used as process gases, and in dry etching, various etchings are also used. gas.

A system for exhausting a process chamber is connected to each other by a process chamber, a vacuum pump, a scrubber or the like by an exhaust line. At this time, the exhaust gas discharged from the self-made process chamber varies depending on the process, but may include a gas molecule or an unreacted precursor in an aerosol state. (precursor), solid seed crystal, etc., may further contain an inert gas as a carrier gas. The exhaust gas flows into the vacuum pump along the exhaust line, and the exhaust gas is compressed in a high temperature state of 100 ° C or higher inside the vacuum pump, thereby inducing phase variation of the constituent elements of the exhaust gas, and it is easy to form solid solidity inside the vacuum pump. The by-products are responsible for the failure of the vacuum pump, and as a result, an unexpected process interruption is caused.

As a prior method for improving the failure of a vacuum pump due to exhaust gas, a purging gas is injected into a vacuum pump that is pumping exhaust gas, and a partial pressure of a component capable of forming a solid by-product in the exhaust gas is reduced. The formation of by-products is minimized. The most common scrubbing gas used is dry-air or nitrogen.

These exhaust gases are highly toxic and flammable. They are harmful to the environment when released to the atmosphere. Therefore, it is necessary to convert the harmless substances before discharge. So far, in most cases, after the vacuum pump The end scrubber functions as the conversion process. The pressure from the back end of the vacuum pump is close to atmospheric pressure, so the scrubber used is a common combustion-based Burn-wet, Heat-wet type, or a dry or wet treatment form using a catalyst, which has decomposition efficiency and generates a large amount of nitrogen compounds. (NO _x ), problems such as frequent and complicated management are required. Recently, the plasma scrubber technology introduced from the same vacuum pump back end using atmospheric piezoelectric slurry has limitations in practical use due to high power consumption and difficulty in improving processing efficiency.

A more effective method for solving the problem of particles or the like in which a solid phase is deposited inside the vacuum pump due to exhaust gas is to provide a hot trap or a cold trap to the exhaust line. However, such methods have limitations due to higher energy consumption and lower processing efficiency. Recently, in order to comprehensively improve the installation of the exhaust line at the same time For the problem of using a common atmospheric air scrubber at the back of the vacuum pump, try adding a low-pressure plasma device to the front end of the vacuum pump, and reconfiguring it in the form of main equipment - low pressure plasma device - vacuum pump - scrubber The overall exhaust system achieves good results. The low-pressure plasma device for such a purpose has a configuration different from that of the conventional atmospheric piezoelectric slurry device in order to achieve easy driving and performance at a low pressure.

Korean Patent No. 1065013 discloses a plasma reactor technique for decomposing exhaust gas by a method of applying an alternating current (AC) driving voltage to cause dielectric barrier discharge. However, the above prior art has the following problems, and there is a limitation in the application in an actual process requiring 24 hours and 365 days of continuous operation: during the occurrence of dielectric barrier discharge, ions in the plasma are continuously in a nearly vertical manner. The incident touches the surface of the dielectric body, and sputtering or erosion of the surface of the dielectric body occurs, so that the discharge environmental conditions due to the deformation of the dielectric substance change, and the parts replacement cycle becomes short. Further, when the exhaust gas contains a fluorine-based or chlorine-based gas, the surface erosion of the dielectric body and its influence become severe. Therefore, there is a need to develop a technique for preventing erosion of the surface of a dielectric body in a plasma decomposition apparatus that decomposes a fluorine- or chlorine-based exhaust gas.

The problem to be solved by the present invention is to provide an exhaust gas which is not only effective in decomposing an exhaust gas containing a fluorine-based and/or chlorine-based gas but also effectively preventing ions inside the plasma reactor, thereby being practically used. A low pressure plasma reactor for the decomposition of exhaust gas in an operating environment requiring 24 hours and 365 days of continuous operation.

The inventors of the present invention have found that the present invention has been completed by long-term research: if the direction of movement of ions is not directed toward the inside of the plasma reactor, a magnetic field is applied to apply the lorenz force to the ions, but only When the size is equal to or greater than the fixed value depending on the type of the ion, the corrosion can be effectively suppressed.

The present invention provides a low pressure plasma reactor for exhaust gas treatment, which is a low pressure plasma reactor for decomposing exhaust gas discharged from a self-made chamber, the low pressure plasma reactor comprising: a dielectric tube The exhaust gas passes through; a pair of ground electrodes are located at both ends of the dielectric tube in an extended manner of the dielectric tube; and the driving electrode is formed to be spaced apart from the pair of ground electrodes to cover the length direction of the dielectric tube a ring shape of the outer surface is connected to the alternating current power supply unit, and a magnetic field generating unit is configured to be insulated and covered outside the drive electrode in order to form a magnetic field in the longitudinal direction of the dielectric tube; and a housing In the case where the crack of the dielectric tube is generated, the exhaust gas is prevented from flowing out to the outside, and the outside of the drive electrode and the outside of the magnetic field generating portion are sealed and sealed in order to block the electromagnetic wave from being radiated to the outside; And the intensity of the magnetic field formed by the magnetic field generating portion along the longitudinal direction of the dielectric tube is limited to (m _i : plasma ion mass, e: charge amount, τ: mean collision time).

Moreover, the present invention provides a low-pressure plasma reactor for exhaust gas treatment, wherein the low-pressure plasma reactor further includes a conductive elastic buffer portion for realizing the driving electrode and the dielectric tube. The buffering and the bonding are interposed between the driving electrode and the dielectric tube.

Further, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein the conductive elastic buffer portion is a graphite sheet, a conductive polymer material sheet, or a mesh foam.

Further, the present invention provides a low-pressure plasma reactor for exhaust gas treatment, wherein the magnetic field generating portion is a solenoid coil, and the magnetic field strength is adjusted by a power source connected to the coil.

Further, the present invention provides a low-pressure plasma reactor for exhaust gas treatment, wherein the magnetic field generating portion is a Helmholtz coil, and the magnetic field strength is adjusted by a power source connected to the coil.

Further, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein _mi is the mass of fluoride ion (F ^- ) or chloride ion (Cl ^- ), The value is 0.01 T.

Further, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein the magnetic field generating portion is a cylindrical permanent magnet.

Moreover, the present invention provides a low-pressure plasma reactor for exhaust gas treatment, wherein a portion of the ground electrode that is in contact with the dielectric tube is a flange structure, and the housing is formed with the dielectric tube The cylindrical shape arranged in a concentric manner has its both end faces connected to the flange faces, and forms a double chamber together with the dielectric tube.

Further, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein the double chamber comprises a cooling device that uses atmospheric, nitrogen, or a coolant as a cooling medium.

Moreover, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein the cooling device comprises a temperature sensor, a pressure sensor, or a gas sensation in the dual chamber. The detector uses the measured value feedback control cooling degree of the above sensor.

Moreover, the present invention provides a low pressure plasma reactor for exhaust gas treatment, wherein the low pressure plasma reactor is disposed between a process chamber and a vacuum pump, or constitutes The booster pump of the above vacuum pump is connected to a backing pump.

Further, the present invention comprises a low pressure plasma reactor for exhaust gas treatment, wherein the housing further includes a sensor portion that senses exhaust gas leaking from the dielectric tube.

Further, the present invention provides a low pressure plasma reactor for exhaust gas treatment, which is a low pressure plasma reactor for decomposing exhaust gas discharged from a self-made process chamber, the low pressure plasma reactor comprising: a booster pump Exhausting the exhaust gas from the exhaust port of the processing chamber; a first grounding electrode of the tubular shape, one end portion of which is connected to an exhaust port of the booster pump for exhaust gas passage; and a dielectric tube having a distal end portion thereof And the other end portion of the tubular first ground electrode is coupled by the flange to supply the exhaust gas; the tubular second ground electrode has a distal end portion and the other end of the dielectric tube The end portion is coupled to allow the exhaust gas to pass through; the auxiliary pump is configured to exhaust the exhaust gas from the other end portion of the second ground electrode; and the driving electrode is formed to be spaced apart from the first ground electrode and the second ground electrode to cover the The ring shape of the outer surface in the longitudinal direction of the dielectric tube is connected to the AC power supply unit, and the magnetic field generating unit is configured to be insulated and covered outside the drive electrode in order to form a magnetic field in the longitudinal direction of the dielectric tube; And housing a cylindrical shape arranged concentrically with the dielectric tube to seal the outer portion of the driving electrode and the outer portion of the magnetic field generating portion, and both end faces of the housing are respectively in contact with the flange surface; and the shell The body and the dielectric tube constitute a dual chamber, and the double chamber includes a cooling device that uses atmospheric, nitrogen or a coolant as a cooling medium. The cooling device is in the double chamber, and the cooling device includes a temperature sensor. , pressure sensor, or gas sensor.

The plasma reactor of the present invention has the following effects.

1. The plasma reactor of the present invention can decompose the vapor deposition precursor discharged from the self-made chamber, a part of the initial reactant, and/or the etching gas and cause it to flow into the vacuum pump, thereby suppressing the solid phase particles inside the vacuum pump. Or the formation and growth of the film prevents unanticipated failure of the vacuum pump, thereby preventing the vacuum process advancement interruption and wafer scrap. Moreover, since it has a vacuum region located at the front end of the vacuum pump, it can greatly reduce power consumption compared with the atmospheric piezoelectric device.

2. In the plasma reactor of the present invention, the electrode for forming the plasma is not located in the inner region of the dielectric tube through which the exhaust gas passes, so that corrosion of the electrode due to the exhaust gas and a decrease in the exhausting ability due to the electrode can be eliminated.

3. The plasma reactor of the present invention utilizes an AC power source having a frequency lower than RF (Radio Frequency), so that it can span a wide pressure range and easily realize plasma generation and maintenance, thereby eliminating the need for electricity. A separate carrier gas or pressure regulating device formed by the slurry easily forms a plasma on the exhaust line, and maintains a plasma state even if a sudden pressure fluctuation due to a continuous process step occurs.

4. The plasma reactor of the present invention is provided with a magnetic field generating portion, which can effectively prevent sputtering or etching of the dielectric body by reducing the angle of ions incident on the surface of the dielectric body exposed to the plasma in a nearly vertical manner. Therefore, it is possible to suppress severe corrosion of the surface of the dielectric body in the decomposition environment by the exhaust gas containing the fluorine-based or chlorine-based gas, and thus it is possible to realize practical use in a use environment requiring continuous operation.

5. The coil-type magnetic field generating portion applied to the plasma reactor of the present invention can adjust the amount of current flowing into the coil to easily adjust the intensity of the magnetic field, and thus can be efficiently formed according to an etching environment generated by incident ions. The size of the magnetic field that actually obtains the etching improvement effect is responsible for the erosion problem inside the plasma reactor.

6. The plasma reactor of the present invention includes a substantially double-chambered casing that covers the outside of the magnetic field generating portion to protect the internal structure, and also prevents process gas when a dielectric tube is cracked. It flows out to the outside to block the emission of electromagnetic waves to the outside.

11‧‧‧Processing chamber

12‧‧‧Vacuum pump

12a‧‧‧ booster pump

12b‧‧‧Support pump

13‧‧‧ scrubber

14‧‧‧Processing chamber exhaust line

15‧‧‧Vacuum pump exhaust line

50‧‧‧ plasma reactor

51‧‧‧Ground electrode

51a‧‧‧Flange

52‧‧‧ dielectric tube

53, 53b‧‧‧ drive electrodes

53a‧‧‧elastic buffer

53a1‧‧‧elastic buffer 1

53a2‧‧‧elastic buffer 2

53b1‧‧‧First drive electrode

53b2‧‧‧second drive electrode

54‧‧‧Magnetic field generation department

54a‧‧‧Solenoid coil

54b1, 54b2, 54b3‧‧‧ Helmholtz coils

54c‧‧‧ permanent magnet

55‧‧‧Shell

56‧‧‧ valve

58‧‧‧Sensor Department

66‧‧‧ Collision

77‧‧‧Exhaust

88‧‧‧Exhaust

100‧‧‧ surface

200‧‧‧ ions

Fig. 1 is a view schematically showing a state in which a low-pressure plasma reactor for exhaust gas treatment according to an embodiment of the present invention is connected between a process chamber and a vacuum pump.

Fig. 2 is a view schematically showing a state in which a low-pressure plasma reactor for exhaust gas treatment according to an embodiment of the present invention is connected between a booster pump and a backing pump constituting a vacuum pump.

Fig. 3 is a view schematically showing a ground electrode, a drive electrode, and a magnetic field generating portion in the low-pressure plasma reactor for exhaust gas treatment of the present invention.

Fig. 4 is a view for explaining an electric field and a plasma formed in a plasma reactor when a power source is applied to the ground electrode and the drive electrode structure of Fig. 3.

FIG 5 is a fluorine ion (F ^-) in a near vertical manner when incident on the surface of the oxide-based Al-Y, Al ₂ O ₃ and Y ₂ O ₃ and constituting ratio and applied to the fluoride ions (F ^-) of The surface etch rate corresponding to the acceleration voltage (the magnitude of the electric field).

Fig. 6 is a view for explaining a structure of a dielectric tube, a ground electrode, a drive electrode, an elastic buffer portion, a magnetic field generating portion, and a casing in the plasma reactor of the present invention.

Fig. 7 is a view showing a structure of a casing including a cooling device and a sensor according to an embodiment of the present invention.

Figure 8 is a diagram showing the use of a solenoid coil as a magnetic field generation in accordance with an embodiment of the present invention. The combined state and decomposition state of the plasma reactor.

Fig. 9 is a view showing a coupled state and an exploded state of a plasma reactor in which a Helmholtz coil is used as a magnetic field generating portion according to an embodiment of the present invention.

Fig. 10 is a view showing a coupled state and an exploded state of a plasma reactor in which a cylindrical permanent magnet is used as a magnetic field generating portion according to an embodiment of the present invention.

Fig. 11 is a view for explaining a change in the trajectory of the charge particles accelerated by the electric field in the plasma reactor due to the magnetic field generated by the magnetic field generating portion.

Figure 12 is a diagram showing the potential and particle density distribution of a region adjacent to the inner surface of the dielectric tube in the plasma reactor.

Figure 13 is a view showing a single charge particle and charge due to kinetic energy (E _K ) and surface incident angle (θ) incident on the surface of the dielectric body in the presence of a magnetic field in the direction α with respect to the dielectric tube axis. The degree of etching of the surface of the dielectric caused by the sputtering of the particle flux.

Fig. 14 is a view showing changes in the etching rate of the surface of the dielectric body corresponding to the intensity of the magnetic field when no magnetic field is applied when a magnetic field parallel to the dielectric tube axis is applied.

Various embodiments are disclosed with reference to the drawings. In the following description, numerous specific details are disclosed in one or more embodiments in order to facilitate an understanding of the whole. However, it should be understood that the various embodiments can be carried out even if the specific details are not present. The following description and specific examples of the above embodiments are described in detail with reference to the accompanying drawings. However, the exemplifications are illustrative, and some of the various methods may be utilized in accordance with the principles of the various embodiments, and the description is intended to include all such embodiments and equivalents.

A number of embodiments and features are presented by means of a device that can include multiple components and components. Moreover, it should be understood and understood that a plurality of devices may include additional components and components, and/or may not include all of the components and components referred to in connection with the drawings.

The "embodiment", "example", "exemplary" and the like used in the present specification are not to be construed as being limited to any of the embodiments or designs described. The terms "chamber", "electrode", "housing", "pump" and the like as used hereinafter generally refer to a vacuum-related entity.

Also, the term "or" means an inclusive "or" and not an exclusive "or". That is, "X uses A or B" means one of natural inclusive permutations when it is not specified differently or the context is not clear. In other words, when X uses A or X to use B or X to use all of A and B, "X uses A or B" can be applied to any of the cases. In addition, the terms "and/or" used in the present specification are to be understood as meaning and encompassing as many combinations as possible of one or more of the listed related items.

In addition, the terms "including" and/or "including" mean that there are corresponding features, steps, operations, components, and/or components, but it should be understood that one or more other features are not excluded or added. Steps, actions, components, components, and/or combinations thereof. In addition, the singular expression "a" or "an" or "an" or "an"

The plasma reactor (50) of the present invention is disposed between a process chamber (11) for realizing film formation or dry etching in a vacuum environment and a vacuum pump (12) for decomposing unreacted gas and washing in a low pressure environment. Net gas, or exhaust gas of initial reactants (77) The plasma reactor comprises: a dielectric tube (52) for passing the exhaust gas (77) containing the unreacted gas; and an electrode (51, 53) for forming an inner region of the dielectric tube a plasma generating portion (54) covering the outside of the dielectric tube for generating a magnetic field substantially parallel to the longitudinal direction of the dielectric tube to mitigate the inner surface of the dielectric tube caused by ion sputtering Corrosion; and a cylindrical casing (55) covering the outside of the magnetic field generating portion and arranged in a concentric manner with the dielectric tube.

Plasma refers to a state in which molecules, atoms, electrons, and ions coexist, and charged particles such as electrons or ions move by an electric field and a magnetic field formed in a space. Upon exposure to the surface (100) of the plasma, collision of ions (200) occurs on the surface (100) by the plasma potential, and erosion due to collision of the accelerated ions (200) occurs.

Such erosion is caused by physical sputtering or chemical reaction, and when reactive with ions that can chemically react with the surface, reactive ion etching can be caused and accelerated. In the present specification, the term "erosion" is used in terms of all inclusive meanings including sputtering due to ion collision, corrosion due to chemical reaction, and etching accelerated by collision of reactive ions.

A fluorine (F)-based or chlorine (Cl)-based gas is used in a deposition process or a cleaning process of a semiconductor, a display device, or a solar cell process. As a specific example, in the process of atomic layer vapor deposition oxide (ALD-Oxide) or atomic layer vapor deposition nitride (ALD-Nitride), a liquid HexaChlorodisiline (Si ₂ Cl ₆ ) precursor is used ( precursor), in dry etching process, such as by using CF _4, CHF _3, SF ₆ or the like etching gas, or in washing processes, the use of NF _3, ClF ₃ and the like a large amount of fluorine-based or chlorine-based gas. The gas and precursor decompose after flowing into the plasma reactor to form a plasma containing a large amount of activated fluoride ions (F ^- ), chloride ions (Cl ^- ), and radicals. The ions are accelerated by the potential difference applied to the electrodes, collide with the surface of the dielectric body to cause surface etching, and at this time, physical sputtering is caused on the surface of the dielectric body, or fluorine or chlorine compounds are formed on the surface of the dielectric body, and the generated compound is formed. Volatilizes and causes erosion of the material to significantly shorten the life of the plasma reactor.

One of the methods for preventing dielectric corrosion as described above is to use a dielectric material excellent in etching resistance. For example, a powder of alumina (Alumina, Al ₂ O ₃ ) and yttrium oxide (Yttria, Y ₂ O ₃ ) is used for sintering, or the sputtering resistance of the alumina material is excellent. A method such as ruthenium oxide, which does not fundamentally solve the problem of erosion caused by plasma even if a high-priced material is utilized.

The present invention is intended to control the trajectory of ions (200) colliding with the surface (100) exposed to the plasma to solve the erosion problem of the material, and is not an attempt on the material.

A process chamber (11) for a thin film process such as film formation or etching of the prior art is connected to a vacuum pump (12) by a process chamber exhaust line (14), a vacuum pump (12) and a scrubber (13) It is connected by a vacuum pump exhaust line (15). The exhaust gas containing the precursor for thin film evaporation can form a crystal nucleus under specific temperature and pressure conditions and be particleized, and the particles generated in the process chamber grow in the exhaust process and flow into the vacuum pump or the scrubber, Or when the vacuum pump or the scrubber is particleized and accumulated, the vacuum pump or the scrubber is gradually damaged.

Fig. 1 is a view schematically showing a state in which a low-pressure plasma reactor (50) for exhaust gas treatment according to an embodiment of the present invention is connected between a process chamber (11) and a vacuum pump (12). In an embodiment of the invention, the process chamber (11) and the vacuum pump (12) It is connected by a process chamber exhaust line (14), and the vacuum pump (12) and the scrubber (13) are connected by a vacuum pump exhaust line (15) in the middle of the process chamber exhaust line (14). , set the low pressure plasma reactor (50). In an embodiment of the invention, the vacuum pump (12) includes a booster pump (12a) and a backing pump (12b). The plasma reactor (50) functions to decompose the exhaust gas including the exhaust gas containing the vapor deposition precursor or a part of the initial reactant or the reactive etching gas, which is moved by the self-made chamber, to prevent particles from flowing into the vacuum pump (12), Or a metal film is formed inside the vacuum pump to protect the vacuum pump. Moreover, since the exhaust gas contains a large toxicity and flammability, the plasma reactor (50) is a primary particle which is decomposed before the scrubber, and is environmentally harmful if it is released to the atmosphere, a metal non-metallic precursor, or After the reactive etching gas is transferred to the scrubber, the total decomposition efficiency of the harmful substances is greatly improved.

Fig. 2 is a view schematically showing a low pressure plasma reactor (50) for exhaust gas treatment according to an embodiment of the present invention connected to a booster pump (12a) and a backing pump (12b) Between the states. The plasma reactor (50) according to an embodiment of the present invention is because the booster pump (12a) forms a strong exhaust gas flow, so that the lighter decomposed particles generated in the plasma reactor can be completely eliminated to the process chamber. The possibility of countercurrent. The reason is that if the ions generated in the plasma reactor flow back to the process chamber, the process conditions can be changed to affect the process.

Fig. 3 is a view schematically showing a ground electrode (51), a drive electrode (53), and a magnetic field generating portion (54) of the low-pressure plasma reactor (50) for exhaust gas treatment of the present invention. Referring to Figure 3a, the exhaust gas (77) discharged from the self-contained chamber flows into the exhaust gas input port of the plasma reactor. In an embodiment of the invention, the portion of the exhaust gas input port formed at both ends of the plasma reactor is composed of a metal body and functions to form a ground of the plasma. The function of the electrode (51). The ground electrode is formed in a tubular shape, and the dielectric tubes are in contact with each other in a sealed form. In an embodiment of the invention, the tubular ground electrode (51) and the dielectric tube (52) are coupled to each other by a flange (51a). In an embodiment of the invention, the drive electrode (53b) is spaced apart from the ground electrode (51) at a predetermined interval, and the dielectric tube (52) is wrapped in a ring shape via an elastic buffer portion (53a). External surface. In an embodiment of the invention, the magnetic field generating portion (54) is formed to be insulated and covered outside the driving electrode. The dielectric tube (52), the drive electrode (53b), and the outside of the magnetic field generating portion (54) are covered by a casing (55). In such an electrode arrangement, the driving electrode (53) is separated from the region through which the exhaust gas passes, so that the problem of electrode corrosion caused by the exhaust gas and the problem of the exhausting ability due to the electrode can be completely eliminated. Fig. 3b is a view showing another driving electrode 1 (53b1) and a driving electrode 2 (53b2) which are two single driving electrodes according to another embodiment of the present invention, which are separated by an elastic buffer portion 1 (53a1) and an elastic buffer portion 2 (53a2), respectively. The shape of the outer surface of the dielectric tube (52) is provided in a manner spaced apart from each other.

Fig. 4 is a view for explaining an electric field and a plasma formed in a plasma reactor when a power source is applied to the ground electrode and the drive electrode structure of Fig. 3; Referring to FIG. 4a, an exhaust gas (77) is input and exhausted (88) (a fixed pressure exhaust gas exists inside the dielectric tube), and if an AC voltage is applied to the driving electrode (53b), the driving electrode (53b) and the ground electrode are applied. The movement of electrons starts between (51), decomposing the exhaust gas and generating plasma. At this point, the ions accelerate in the plasma region and cause an ion collision (66) that continues in a nearly vertical manner on the surface of the dielectric tube. Referring to FIG. 4b, in a plasma reactor in which a driving electrode of a separate form is formed, a gap is generated between the driving electrode and the ground electrode (51), between the first driving electrode (53b1) and the second driving electrode (53b2). Plasma. In this case, the ions also enter the collision (66) into the surface of the dielectric tube in a nearly vertical manner. And erosion occurs on the surface of the dielectric tube. As shown in the figure, the driving electrode is disposed to cover the outer surface of the dielectric tube, and is applied to the electric tube due to plasma under the condition of applying an AC voltage of several hundreds of kilohertz (kHz) for generating plasma. The erosion caused by the internal surface is more serious. The reason for this is that if a voltage is applied between the driving electrode and the ground electrode, an electric field is formed in a direction close to the inner surface of the dielectric tube in a region where the driving electrode is provided, so that ions inside the plasma are accelerated, and are close to each other. The vertical direction continues to collide with the inner surface of the dielectric tube.

The collision of the plasma ions as described above etches the surface of the dielectric tube. FIG 5 is a fluorine ion (F ^-) in a near vertical manner when incident on the surface of the oxide-based Al-Y, Al ₂ O ₃ and Y ₂ O ₃ and constituting ratio and applied to the fluoride ions (F ^-) of The surface etch rate corresponding to the acceleration voltage (the magnitude of the electric field). In the case of a dielectric tube produced by sintering a high-priced material such as a mixed powder of alumina (Alumina, Al ₂ O ₃ ) and yttrium oxide (Yttria, Y ₂ O ₃ ), it is also impossible to prevent etching of plasma ions. Appropriate method (Lee Seong Min, Korean Ceramic Technician).

6 is a view showing a dielectric tube (52), a ground electrode (51), a drive electrode (53b), an elastic buffer portion (53a), and a magnetic field generating portion (54) in the plasma reactor (50) of the present invention. And the structural diagram of the casing (55). In order to effectively solve the problem of erosion caused by the internal surface of the plasma reactor in which the drive electrode is provided in the form of the outer surface of the dielectric tube, a device for forming a magnetic field is added to the plasma region in the present invention. In an embodiment of the invention, the drive electrode (53b) is surrounded by the dielectric buffer (53) so as to cover the dielectric tube (52). The elastic buffer portion as described above selects the conductive elastic buffer portion so as not only to exhibit mechanical buffering and close-contact functions, but also to exhibit a conductive function at the same time. In an embodiment of the invention, the elastic buffer portion is a graphite sheet, a conductive polymer material sheet, or a metal mesh cotton. (foam).

The means for forming a magnetic field may be disposed outside the dielectric tube. In an embodiment of the invention, the magnetic field generating portion may be constituted by a solenoid coil to which a power source is connected, a Helmholtz coil, or a permanent magnet. When a magnetic field is introduced into the plasma region, the charged particles are subjected to the Lorentz force, so the trajectory of the charged particles inside the plasma changes. If the amount of current flowing into the coil is adjusted, the magnetic field strength can be adjusted, thereby The magnetic field strength adjusts the angle of incidence of the incident ions.

However, if the magnetic field strength does not reach a fixed value, the surface etching rate of the ions does not change as described below, or conversely, the etching rate becomes high. Therefore, according to the etching environment formed by the incident ions, the magnetic field strength which can substantially obtain the etching improving effect can be efficiently formed, thereby coping with the problem of erosion inside the plasma reactor.

Further, the plasma reactor of the present invention is configured to include a casing (55) in a practical double chamber form covering the outside of the magnetic field generating portion, thereby protecting the internal structure and generating a dielectric tube crack. In this case, it is also possible to prevent the process gas from flowing out to the outside and to block electromagnetic waves from radiating to the outside. a portion of the ground electrode that is in contact with the dielectric tube is a flange structure, and the housing has a cylindrical shape that is concentric with the dielectric tube, and both end surfaces thereof are in contact with the flange surface, and The dielectric tubes described above together form a dual chamber. The dual chamber simultaneously has the following functions: a physical seal, which deals with the leakage of the exhaust gas from the space where the plasma is generated, that is, the inside of the dielectric tube; and the blocking, which prevents the electrode from being generated at the driving electrode and/or the magnetic field generating portion. The electromagnetic waves radiate to the outside.

Fig. 7 is a view showing a structure of a casing including a cooling device and a sensor according to an embodiment of the present invention. The double chamber space formed by the casing may include a cooling unit and a sensor unit (58) that use a cooling medium such as air, nitrogen, or a coolant, and a valve (56) that adjusts the cooling medium. Composition, can be controlled simply as needed The system is cooled or cooled in a feedback control mode that is interlocked according to the sensor value. In an embodiment of the invention, the cooling device includes a temperature sensor and/or a pressure sensor in the dual chamber, and the degree of cooling is controlled by using the measured value of the sensor. In another embodiment of the invention, the housing includes a sensor portion that senses exhaust gas leaking from the dielectric tube.

Fig. 8 is a view showing a coupled state and an exploded state of a plasma reactor in which a solenoid coil (54a) is used as a magnetic field generating portion according to an embodiment of the present invention. Referring to Figure 8, the plasma reactor (50) includes a ground electrode, a dielectric tube (52), a drive electrode (53), a solenoid coil (54a), and a housing (55). In an embodiment of the invention, the ground electrode (51) may be formed on both sides of the longitudinal direction of the dielectric tube (52). The ground electrode (51) may be constituted by an exhaust pipe itself made of metal. In an embodiment of the invention, a dielectric tube having a driving electrode formed on an outer surface thereof and a cylindrical housing (55) externally covering the dielectric tube face the ground electrode (51) in a coaxial manner And fastening and substantially forming a double chamber, thereby protecting a structure such as a solenoid coil, and when the crack of the dielectric tube is generated, the process gas is prevented from flowing out to the outside, and is disposed in a grounded state. It is also possible to block electromagnetic waves generated by the solenoid coil from radiating to the outside. In another embodiment of the invention, the ground electrode and the housing may be in a separate configuration, and the housing may also be formed of a non-conductor. The dielectric tube (52) may be formed of a dielectric substance so as to function as a dielectric according to a voltage applied to the driving electrode (53). In an embodiment of the invention, the dielectric tube (52) may be composed of aluminum oxide, zirconium oxide (ZrO ₂ ), yttrium oxide (Y ₂ O ₃ ), sapphire, quartz tube, glass tube or the like. The drive electrode (53) is formed in a ring shape in which the outer surface of the dielectric tube (52) is coated on the outer surface, and is formed to be spaced apart from the ground electrode (51) by a specific interval, thereby eliminating the cause when located inside the dielectric body. Corrosion caused by exhaust gas and a problem of reduced exhaust efficiency. In an embodiment of the invention, the drive electrodes may be in a unitary configuration. In another embodiment of the present invention, the driving electrodes may be configured in a form in which they are spaced apart from each other or in a plurality of forms in which voltages are applied in different periods from each other. The driving electrode (53) can flow an alternating current whose voltage changes according to a fixed period. The frequency of the alternating current can be an AC current of several to several hundreds of kilohertz (kHz) or an RF current having a higher frequency than the AC current. The frequency of the alternating current is preferably 50 to 500 kHz (kHz) in consideration of the range of the gas pressure at which the plasma is generated and maintained.

When an AC voltage is applied to the driving electrode (53), the dielectric tube can exert a dielectric barrier function on the one hand, and cause a dielectric barrier discharge inside the dielectric tube on the one hand. The solenoid coil (54) may be configured to cover the outside of the above-described drive electrode (53). The number of crimps or the area of formation of the solenoid coil, and the intensity of the current flowing into the coil can be adjusted according to the area of the drive electrode and the diameter of the exhaust line to generate a magnetic field of a magnitude that can effectively prevent the erosion of the inner surface of the dielectric tube. . In an embodiment of the invention, the solenoid coil may be disposed in an overall shape of the covering dielectric tube or beyond the area of the dielectric tube, and the plurality of solenoid coils may be disposed in a connected or separated manner. . In an embodiment of the present invention, the solenoid coil may be in contact with the driving electrode in a form in which the electric wire is coated with an insulating film, or may be provided in a form separated from the driving electrode by a separate unit. In an embodiment of the invention, if a current flows into the solenoid coil, a magnetic field is formed along the axial direction of the dielectric tube.

Fig. 9 is a view showing a coupled state and an exploded state of a plasma reactor in which a Helmholtz coil is used as a magnetic field generating portion according to an embodiment of the present invention. The plasma reactor (50) includes a ground electrode (51), a dielectric tube (52), a drive electrode (53), and a Helmholtz coil (54b1, 54b2, 54b3). If compared with a plasma reactor in which a solenoid coil is selected as a magnetic field generating portion, the grounding electrode, the dielectric tube, and the driving The electrodes and the housing have the same construction and function, but the solenoid coils are replaced by Helmholtz coils (54b1, 54b2, 54b3). The Helmholtz coils (54b1, 54b2, 54b3) are constituted by a plurality of coils which are disposed apart from each other by a distance corresponding to 1/2 of the diameter of the dielectric tube, and the coils provided at the upper and lower portions can be disposed as follows: The upper end and the lower end of the self-dielectric tube are separated by a distance corresponding to 1/2 of the diameter of the dielectric tube. The Helmholtz coil can generate a magnetic field inside the dielectric tube, and the magnetic field formed along the axial direction of the dielectric tube can change the trajectory of the charged particles inside the plasma, and reduce the incident collision to the vertical direction. The angle of incidence of the charged particles on the surface of the tube. The number of Helmholtz coils, the number of windings, and the current intensity flowing into the coil can be adjusted according to the length and diameter of the dielectric tube, the shape of the driving electrode, and the voltage, etc., so as to effectively prevent the inside of the dielectric tube from being generated. The surface of the erosion problem is the size of the magnetic field.

Fig. 10 is a view showing a coupled state and an exploded state of a plasma reactor in which a cylindrical permanent magnet is used as a magnetic field generating portion according to an embodiment of the present invention. The plasma reactor (50) includes a ground electrode (51), a dielectric tube (52), a drive electrode (53), and a permanent magnet (54). The ground electrode (51), the dielectric tube (52), the drive electrode (53), and the casing (55) have the same structure when compared with a plasma reactor in which a solenoid coil is selected as a magnetic field generating portion. And function, but replace the solenoid coil with a permanent magnet (54c) in the form of a cylinder. The permanent magnet in the form of a cylinder is disposed outside the dielectric tube in a state of covering the outside of the driving electrode, and a magnetic field can be generated inside the dielectric tube, and a magnetic field formed along the axial direction of the dielectric tube can cause charged particles inside the plasma. The trajectory of the movement changes to reduce the incident angle of the charged particles that collide with the surface of the dielectric tube in a nearly vertical manner. The magnetic flux of the cylindrical permanent magnet according to the embodiment of the present invention can be determined in consideration of the length and diameter of the dielectric tube, the shape and voltage of the driving electrode, etc., so as to effectively prevent the dielectric tube from being generated. Erosion of the internal surface The size of the magnetic field.

According to an embodiment of the invention, the magnetic field generating device disposed outside the dielectric tube affects the life of the plasma reactor. In particular, when the exhaust gas contains a fluorine-based or chlorine-based gas, the plasma formed inside the dielectric tube contains radicals, ions, active species, and the like having high reactivity, and the magnetic field generating portion of the present invention is in the dielectric tube. A magnetic field parallel to the axial direction is formed to change the incident angle of ions incident on the inner surface of the dielectric tube in a nearly vertical manner to reduce the erosion of the inner surface of the dielectric tube, thereby requiring continuous operation for 24 hours and 365 days. The present invention is actually applied in the application environment.

Fig. 11 is a view for explaining a change in the trajectory of the charge particles accelerated by the electric field in the plasma reactor due to the magnetic field generated by the magnetic field generating portion. Referring to Fig. 11a, in the region where the driving electrodes are provided, the cations of the plasma are accelerated to be incident on the inner surface of the dielectric tube by the negative voltage applied to the driving electrodes and the wall charges formed on the surface of the dielectric tube. At this time, if a magnetic field is formed inside the plasma, the incident angle of the cation changes, as illustrated in Fig. 11b. Referring to Fig. 11b, the cation (200) incident on the surface of the dielectric tube, that is, the "ceramic wall (100)" moves toward the surface of the dielectric tube at a nearly vertical incident angle. If a magnetic field B is formed inside the dielectric tube, the magnetic field is generated. The trajectory of the cation is changed and incident on the surface of the dielectric tube at an incident angle of θ. At this time, the distribution function f _i ( E _K , θ ) of the ions colliding to the wall surface by the incident angle θ and the kinetic energy E _K according to the intensity of the magnetic field can be obtained by the Vlasov equation for describing the plasma. Obtained by numerical calculation.

Figure 12 is a graph showing the potential and particle density distribution of a region adjacent to the inner surface of the dielectric tube in the plasma reactor. Referring to Fig. 12a, if a plasma of a quasi-charge-neutral state is generated in the dielectric tube, electrons that are relatively far faster than the cation collide more frequently to the dielectric wall. The surface of the dielectric adsorbs the colliding electrons at a negative potential, thus forming an electric field in the direction of the wall surface. The electric field formed as described above reduces the electron flux toward the wall surface while increasing the cation flux that collides with the wall surface of the dielectric body. If the electron flux and the cation flux become the same, the charge is not deposited on the surface of the dielectric body to reach a steady state, and a self-bias is formed on the inner surface of the dielectric body. The self-bias voltage is expressed by a sheath potential V _S .

In Formula 1, T _e is the equilibrium state temperature of electrons in the plasma, and m _e and m _i are the masses of electrons and ions, respectively. For example, in low-pressure plasma T _e = 1eV, the fluoride ions (F ^-) or chloride ions (Cl ^-) in the case when the size of the sheath voltage V _S -10 V. In the region where the driving electrode is provided, the ions collide with the inner surface of the dielectric by the sum of the external voltage applied to the electrode and the sheath voltage which can be relatively ignoring the size, and cause sputtering or erosion of the surface of the dielectric body. . The spatial distribution of the cation density n _i and the electron density n _e near the surface of the dielectric is shown in Figure 12b. The following region is called a Debye sheath, and the width is usually within a few mm: the quasi-charge neutral property of the plasma blocked near the surface of the dielectric is impaired, and the cations are deposited to form a negative potential on the surface. The surface of the dielectric body is curved because it is the inner surface of the cylinder, but the width of the Debye sheath and the presheath is much smaller than the radius of the cylinder, so that the surface of the dielectric body can be close to the plane, on the surface of the dielectric. In the periphery, the movement of ions is greatly affected by the Debye sheath and the pre-sheath.

For reference, in the case, the ion distribution function f _i ( E _K , θ ) with time is, for example, the deformed Vlasov equation, ie, Equation 2 below, the etch rate of the dielectric surface due to the cation It can be defined by the following formula 3.

[Formula 2]

In Formula 3, y ₀ ( E _K , θ ) represents an etch rate of a single ion having a kinetic energy E _K and a collision angle θ. α is the angle between the axial direction of the dielectric tube and the direction of the applied magnetic field, and ω = ω _c / ω _p represents the ratio of the cyclotron frequency ω _c to the plasma frequency ω _p .

Fig. 13 is a view showing a single charge particle and a charge particle due to kinetic energy (E _K ), surface incident angle (θ) incident on the surface of the dielectric body in an environment where a magnetic field having a direction α with respect to the dielectric tube axis exists. The degree of etching of the surface of the dielectric caused by flux sputtering. By experiment, it can be known that, in general, as shown probically in Fig. 13a, the etching rate y ₀ ( E _K , θ ) of a single ion having a kinetic energy E _K and a collision angle θ is associated with collision with the wall surface. The kinetic energy of the ions increases in a proportional manner. If the etching rate gradually increases and reaches a maximum value from the normal incidence (θ=90°) to the wall surface reduction θ due to the collision direction of the ions, θ=0°, that is, parallel to the wall surface. When the mode is incident, the etching rate becomes zero. There is a small difference in the collision angle at which the etching rate of a single ion has a maximum depending on the kind of ions, but is substantially in the vicinity of θ=30°. The application of a magnetic field is usually proposed to spatially constrain the plasma, and has hitherto played a useful role. However, in the case of wall sputtering, the effect of the magnetic field is far more complicated than the effect that has hitherto been exerted. If the magnetic field is simply applied to change the trajectory of the ions from normal incidence (θ=90°), As shown in Figure 13a, the sputtering effect is increased instead.

In the case of approaching parallel incidence (θ = 0°) in order to avoid the above situation, a magnetic field of extremely high intensity is required, and thus the above situation is not a realistic countermeasure. The dielectric surface etch rate of the ion to be known is represented by Equation 3, which is an etch rate y ₀ ( E _K , θ ) of a single ion and an ion distribution function f _i ( E _K , θ After multiplying, consider the effect on the overall ion. The distribution function of ions is complicatedly dependent on the incident ion flux, the collision between ions and electrons in the plasma, and the like. The ion flux is defined as the number of ions incident on the wall surface per unit time per unit area, and is roughly proportional to the sin θ with respect to the incident angle θ of the ions, and thus decreases as it changes from normal incidence to parallel incidence. . The case of reducing the etch rate to play the role of locally increasing the y ₀ (E _{K, θ)} of the individual ions. Fig. 13b shows the calculation result of the etching rate value with respect to the direction α of the magnetic field (Plasma Phys. Control. Fusion 50 (2008) 025009). Here, the following can be known: in the case of α=90°, the etching rate does not depend on the strength of the magnetic field, and when the direction of the magnetic field is parallel to the dielectric tube (α=0°), the etching rate is greatly reduced by 70%. about.

In Equation 4, when the direction of the magnetic field is parallel to the dielectric tube (α = 0°), the etching rate Y(0, ω) can be expressed as the product of the incident ion flux and the etching rate of a single ion. The single ion is an angle θ _M = 30° indicating the maximum etching rate, and the angle θ is expressed in the vicinity of the wall surface of the cylinder, and the wall surface incident direction of the ions in the magnetic field perpendicular to the wall surface and the magnetic field in the axial direction. The angle can be expressed by θ = 90° - θ _H , θ _{H is} a Hall angle, and represents an angle between a current and an electric field in a magnetic field, and tan θ _H = ω _c τ. Here, For the cyclotron frequency, τ represents the average collision time of ions within the plasma.

Fig. 14 is a view showing changes in the surface etching rate of the dielectric body corresponding to the intensity of the magnetic field when no magnetic field is applied when a magnetic field parallel to the dielectric tube axis is applied. In the case of low-pressure plasma, the average ion collision time is very long, so the product of the plasma frequency is ω _p τ It is very large around 5×10 ² . According to Figure 14, the intensity of the magnetic field corresponds to ω _c τ = 500 × ( ω _c / ω _p ) At about 5, the etching rate is reduced by about 70%. For example, in the case of low-pressure plasma, in the case of fluoride ion (F ^- ), the plasma frequency is Left and right, when the intensity of the magnetic field is 0.02 T, the cyclotron frequency is . Therefore, it is ω _c τ Around 5, the magnetic field strength 0.02 T is the magnetic field strength to the extent that it can be easily realized, and thus the present technology can be realized very practically.

Referring to Fig. 14, in the case where a magnetic field parallel to the direction of the dielectric tube is applied to the plasma in the dielectric tube, only the following situation can be achieved before the performance of the improvement of the etching rate can be started: no magnetic field is different from expected When the intensity of the magnetic field increases, the etching rate initially increases gradually, and the intensity of the magnetic field is ω _c τ After reaching the maximum etch rate at 1 o'clock, it should be reached to meet The area of the magnetic field strength. The case is equivalent to B in the case of fluoride ion (F ^- ) or chloride ion (Cl ^- ) 0.01 T. That is, when the intensity of the magnetic field is less than 0.01 T, the etching rate is rather high. Therefore, in order to reduce the etching rate, a power source or a permanent magnet should be applied so as to maintain a magnetic field stronger than 0.01 T in the plasma region.

When the theoretical and achievable results as described above are applied to the plasma reactor of the present invention, a magnetic field substantially parallel to the axial direction of the dielectric tube is formed inside the dielectric tube by the proposed magnetic field generating portion. Therefore, the etching rate (degree of erosion) of the surface of the dielectric due to collision of ions inside the plasma can be effectively reduced.

The above description is based on an embodiment to explain the technical idea of the present invention, and therefore, those having ordinary knowledge in the technical field to which the present invention pertains may not depart from the essence of the present invention. Various modifications and changes are made within the scope of sex. Therefore, the embodiments described in the present invention are for explaining the technical idea of the present invention, and are not intended to limit the technical idea of the present invention, and the scope of the technical idea of the present invention is not limited to the embodiment. The scope of the present invention should be construed in accordance with the scope of the application, and all technical ideas that are within the scope of the application are included in the scope of the invention.

51‧‧‧Ground electrode

51a‧‧‧Flange

52‧‧‧ dielectric tube

53a‧‧‧elastic buffer

53b‧‧‧ drive electrode

54‧‧‧Magnetic field generation department

55‧‧‧Shell

77‧‧‧Exhaust

88‧‧‧Exhaust

Claims (12)

A low-pressure plasma reactor for exhaust gas treatment, which is an exhaust gas discharged from a self-made process chamber, the low-pressure plasma reactor comprising: a dielectric tube for passing the exhaust gas; and a pair of ground electrodes to The extended shape of the dielectric tube is located at both ends of the dielectric tube; the driving electrode is formed to be spaced apart from the pair of ground electrodes, and covers a ring shape of an outer surface of the longitudinal direction of the dielectric tube, and is connected The magnetic field generating unit is configured to form a magnetic field in the longitudinal direction of the dielectric tube so as to be insulated and covered outside the driving electrode, and a casing having the following form, that is, When the crack of the dielectric tube is generated, the exhaust gas is prevented from flowing out to the outside, and electromagnetic waves are blocked from being radiated to the outside, and the outside of the driving electrode and the outside of the magnetic field generating portion are sealed and sealed; The strength of the magnetic field formed by the magnetic field generating portion along the longitudinal direction of the dielectric tube is limited to (m _i : plasma ion mass, e: charge amount, τ: average collision time). The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein the low-pressure plasma reactor further comprises a conductive elastic buffer portion for realizing the driving. The buffer and the adhesion between the electrode and the dielectric tube are interposed between the driving electrode and the dielectric tube. The low-pressure plasma reactor for exhaust gas treatment according to claim 2, wherein the conductive elastic buffer portion is a graphite sheet, a conductive polymer material sheet, or a metal Net cotton (foam). The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein the magnetic field generating portion is a solenoid coil, and the power is adjusted by a power source connected to the solenoid coil. Magnetic field strength. The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein the magnetic field generating portion is a Helmholtz coil, and is adjusted by a power source connected to the Helmholtz coil. The magnetic field strength. The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein _mi is a mass of fluorine ion (F ^- ) or chloride ion (Cl ^- ), The value is 0.01T. The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein a portion of the ground electrode that is in contact with the dielectric tube is a flange structure, and the housing is The dielectric tube is arranged in a cylindrical shape concentrically, and both end faces of the housing are respectively in contact with the flange structure, and the housing forms a double chamber together with the dielectric tube. A low pressure plasma reactor for exhaust gas treatment according to claim 7, wherein the dual chamber comprises a cooling device that uses atmospheric, nitrogen, or a coolant as a cooling medium. A low pressure plasma reactor for exhaust gas treatment according to claim 8 of the patent application, wherein The cooling device is in the double chamber, and the cooling device comprises a temperature sensor, a pressure sensor, or a temperature sensor and a pressure sensor, and the measured value of the temperature sensor is used. The measured value of the pressure sensor or the measured value of the gas sensor feedback controls the degree of cooling. The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein the low-pressure plasma reactor is disposed between the process chamber and the vacuum pump, or constitutes an increase of the vacuum pump. Between the pressure pump and the support pump. The low-pressure plasma reactor for exhaust gas treatment according to claim 1, wherein the housing further comprises a sensor portion, the sensor portion being sensible for leaking from the dielectric tube The exhaust gas. A low-pressure plasma reactor for exhaust gas treatment, which is an exhaust gas discharged from a self-made process chamber, the low-pressure plasma reactor comprising: a booster pump for making the exhaust gas from the process Venting the exhaust port of the chamber; a first grounding electrode of the tubular shape, a distal end portion of the first grounding electrode of the tubular shape is connected to the exhaust port of the booster pump for the exhaust gas to pass; a dielectric tube, a distal end portion of the dielectric tube is coupled to the other end portion of the tubular first ground electrode by a flange for the exhaust gas to pass; the tubular second ground electrode is a terminal portion of the tubular second ground electrode is coupled to the other end portion of the dielectric tube by the flange for the exhaust gas to pass through; a pump that discharges the exhaust gas from the other end portion of the tubular second ground electrode; the driving electrode is formed to be the first ground electrode and the tubular second ground electrode A ring shape that covers the outer surface of the dielectric tube in the longitudinal direction is connected to the AC power supply unit, and a magnetic field generating unit is configured to form the magnetic field in the longitudinal direction of the dielectric tube. a structure in which the outer portion is insulated and covered; and a casing having a cylindrical shape arranged in a concentric manner with the dielectric tube to seal the outer portion of the driving electrode and the outer portion of the magnetic field generating portion The two end faces of the housing are respectively connected to the flange; and the casing and the dielectric tube form a double chamber, and the double chamber contains atmospheric, nitrogen, or coolant A cooling device for use as a cooling medium, the cooling device being in the dual chamber, the cooling device comprising a temperature sensor, a pressure sensor, or a gas sensor.