KR20170050622A - Ignitor part - Google Patents

Abstract

The present invention relates to an ignition electrode unit. The ignition electrode unit according to the present invention comprises: an ignition electrode which transfers electro-motive force to a plasma discharge channel; a hollow area which is positioned at the lower portion of the ignition electrode; and a pipe which is connected to the hollow area and the plasma discharge channel and is twisted at a predetermined angle. The ignition electrode unit according to the present invention can process gas processed in a process chamber, into the plasma to have high decomposition efficiency. The ignition electrode according to the present invention has an effect that ignition is well performed on both of process byproduct gas discharged after performing a process for a semiconductor or a display in a process chamber and cleaning byproduct gas discharged after performing cleaning of a process chamber, and is not turned off.

Description

Ignition electrode part {Ignitor part}

TECHNICAL FIELD The present invention relates to an effective plasma ignition, and more particularly, to an ignition electrode portion of a plasma reactor generating a plasma.

Plasma discharges are used in gas excitation to generate active gases including ions, free radicals, atoms, and molecules. Active gases are widely used in various fields and are typically used in a variety of semiconductor manufacturing processes such as etching, deposition, cleaning, and ashing.

In recent years, wafers and LCD glass substrates for manufacturing semiconductor devices have become larger. Accordingly, there is a demand for a plasma source that has a high controllability against plasma ion energy, has a large area processing capability, and is easy to expand. However, as the substrate to be processed becomes larger, the volume of the process chamber is also increased, and a plasma source capable of sufficiently supplying high-density active gas remotely is required.

The remote plasma generator uses various plasma sources depending on the plasma generation method. For example, inductively coupled plasma sources, capacitively coupled plasma sources, and microwave plasma sources have been used in remote plasma generators. In the case of an inductively coupled plasma source, the method employing a transformer is called a transformer coupled plasma. A remote plasma generator using a transformer coupled plasma source has a structure with a magnetic core having a primary winding coil in the chamber body of the toroidal structure.

The magnetic core of the inductively coupled plasma source is formed of a ferromagnetic magnetic material or the like. When the RF power is applied by winding the coil, most of the magnetic field strength (H) A magnetic flux density (B) is concentrated and induced in a magnetic core made of a magnetic magnetic body. The induced magnetic field is formed in the direction of the electric field (E) inside the magnetic core by the magnetic field and normal by the Amperelaw. At this time, an electric field of a large intensity is induced in a portion where plasma generation is desired, as compared with a radio frequency antenna used in a general inductively coupled plasma method. Therefore, by using a radio frequency antenna using a magnetic core, it is possible to obtain a high-density plasma capable of increasing the dissociation and ionization rate of the plasma source gas even at a power lower than the power of the general inductively coupled plasma.

In the above-described plasma processing apparatus, there is a method of treating the exhaust gas discharged after the cleaning as well as the plasma processing used in the process or cleaning recently by the plasma processing apparatus. PFCs (perfluorocompounds) are used in etching and cleaning processes using plasma in the semiconductor / display process, and their usage has also been increasing with the expansion of the semiconductor / display market. The PFCs used in the semiconductor / display process include CF ₄ , CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , C ₄ F ₈ , NF ₃ and SF ₆ , which are classified as representative of global warming gases have.

Currently, methods for treating PFCs discharged from a semiconductor / display process include plasma, chemical filtration, catalysis, pyrolysis, and incineration. Among them, the method of treating PFCs by plasma is small in size, simple to install, and easy to control the operating parameters. The method of using plasma for treating PFCs can be divided into a normal-pressure thermal plasma installed at the rear of the vacuum pump and a low-pressure glow plasma installed at the front of the vacuum pump, depending on the installation position of the plasma reactor. The atmospheric thermal plasma method is a method in which PFCs are pyrolyzed by using an arc discharge at a temperature of several thousand K or more, and is partially adopted in domestic semiconductor processes. However, the atmospheric pressure treatment method has an excellent advantage in terms of the decomposition rate due to the high temperature of the thermal plasma, but has a weak point in energy efficiency, which is equivalent to the power consumed per unit g, as compared with other treatment methods. This is because it is difficult to obtain a bulky plasma at normal pressure and efficient heat transfer is difficult with the process gas and power is wasted because it decomposes nitrogen, which is a purifying gas used in a vacuum pump, together with the process gas. On the other hand, in the low-pressure plasma method, it is possible to avoid a waste of energy consumed in the heating of nitrogen, which is a purifying gas, by decomposing / treating the PFCs at the front end of the vacuum pump, and to easily obtain a bulky plasma, Respectively. In addition, the low-pressure plasma method can control the size of the particles generated in the etching process and the chemical species of the byproducts, so that the vacuum pump has a function to dramatically increase the life of the vacuum pump. Therefore, there is a need for a plasma processing apparatus for easily dissociating and plasmaizing process by-products or cleaning by-product gases. Techniques that can easily dissociate gases require effective ignition electrodes with an effective gas distribution, high ignition rates, and no offsets during the process.

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the problems of the prior art described above, and it is an object of the present invention to provide a plasma reactor for reducing exhaust gas, To provide an ignition electrode for decomposing harmful gases efficiently.

The present invention relates to an ignition electrode. The ignition electrode of the present invention comprises: an ignition electrode for transferring an electromotive force to a plasma discharge channel; A hollow region located below the ignition electrode; And a tube connected to the hollow region and the plasma discharge channel and angled at an angle.

In addition, the pipe includes a plurality of porous holes therein.

Further, the lower portion of the ignition electrode is formed of an insulating plate, which is a dielectric.

Further, the insulating plate is sapphire.

The ignition electrode portion according to the present invention can treat the gas treated in the process chamber with a plasma so as to have a high decomposition efficiency. In addition, the ignition electrode according to the present invention is effective in igniting both the process by-product gas discharged after the semiconductor or display process is performed in the process chamber and the cleaning by-product gas discharged after cleaning the process chamber and is not ignited .

1 is a schematic view showing an exhaust gas purifying system.
2 is a side view showing a plasma reactor for exhaust.
3 is an exploded perspective view showing a plasma reactor for exhaust.
4 is a plan view of an exhaust plasma reactor including a plurality of plasma discharge tubes.
5 to 6 are views of a plasma reactor for exhaust including a steam injection hole.
Figs. 7 to 8 are diagrams showing ignition electrodes of a plasma reactor for exhaust.
9 is a view of a magnetic core assembly for an exhaust plasma reactor.
10 is a view showing a combination of magnetic cores.
11 is a view showing a primary winding hole of a plasma reactor for exhaust.
Figures 12-15 illustrate various embodiments in which the primary winding is wound.

For a better understanding of the present invention, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. The embodiments of the present invention may be modified into various forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. The present embodiments are provided to enable those skilled in the art to more fully understand the present invention. Therefore, the shapes and the like of the elements in the drawings can be exaggeratedly expressed to emphasize a clearer description. It should be noted that the same components are denoted by the same reference numerals in the drawings. Detailed descriptions of well-known functions and constructions which may be unnecessarily obscured by the gist of the present invention are omitted.

Hereinafter, an exhaust gas purifying system will be described with reference to the accompanying drawings.

1 is a schematic view showing an exhaust gas purifying system.

The process chamber 10 for the semiconductor and display processes is connected to the exhaust line 12 and the pump 16 at the rear end. In the production of various semiconductor devices and recently in the production of liquid crystal rapidly developed, since the gas emitted after use is toxic and flammable, it greatly influences the human body and greatly affects the global warming. Therefore, . Hereinafter, the gas used in the semiconductor device manufacturing process will be described as follows. First, in the etching process, CF ₄ , SF ₆ , CHF ₃ , and C ₂ F, which are mainly used for etching silicon oxide, silicon nitride, and polycrystalline silicon, ₆ , fluorine gases such as SiF ₄ , F ₂ , HF and NF ₃ , and fluorine gases such as Cl ₂ , HCl, BCl ₃ , SiCl ₄ , CCl ₄ and CHCl ₃ used for etching aluminum and silicon There are chlorine gases and bromine gases such as HBr and Br ₂ used in the etching process of aluminum with trench-etch or Cl ₂ , followed by chemical vapor deposition (CVD) , Chemical Vapor Deposition) process, Silane, N ₂ and NH ₃ are often used in the chamber. Particularly in the PECVD process, PFC or ClF ₃ is used to clean the chamber interior, where SiF ₄ can be produced. These gases are highly toxic, corrosive and oxidizing, and if they are discharged as they are, there is a possibility of causing many problems in the human body, the global environment, and the production equipment itself. Therefore, according to the exhaust gas purifying system of the present invention, harmful PFCs (perfluorocompounds) are not directly discharged through the pump 16 but exhausted after the harmful gas is decomposed by the exhausting plasma reactor 14 . As shown in the figure, when there is a gas which has not been treated by the exhaust plasma reactor 14, for example, by-product, insoluble gas, or ignitable gas, the scrubber 18 ) Can be used. The scrubber 18 may be a wet scrubber or a combination of a dry scrubber and a dry scrubber. The exhaust plasma reactor 14 and the scrubber 18 can be used respectively, and a system can be constituted by a combination thereof. In the case of the combination of these, the harmful gas can be decomposed through the scrubber 18 when the exhaust plasma reactor 14 located at the front end of the exhaust pump is repaired or malfunctioned. Therefore, the semiconductor and display process of the process chamber 10 There is an advantage that the plasma reactor 14 can be operated regardless of whether the exhaust plasma reactor 14 is malfunctioning or not.

FIG. 2 is a side view showing a plasma reactor for exhaust, and FIG. 3 is an exploded perspective view showing a plasma reactor for exhaust.

As shown in FIGS. 2 and 3, the plasma reactor 14 for exhaust gas flows in and out of the gas as a process by-product through the gas inlet 20 and the gas outlet 32. The gas introduced through the gas inlet 20 passes through the second body 27 including the first body 22 and the plurality of plasma discharge tubes 26 equipped with the plurality of magnetic cores 28, ). The gas inlet 20 and the gas outlet 32 are connected to the exhaust line (not shown), and SUS is used as the material. The second body 27 including the first body 22 and the plurality of plasma discharge tubes 26 equipped with the plurality of magnetic cores 28 is made of aluminum or an aluminum alloy. The plasma discharge tube 26 includes a tube in which a cylindrical plasma discharge channel is formed inside a hexahedron shape. The second body 27 is formed so that a plurality of plasma discharge tubes 26 are connected to the lower holes. Therefore, the second body 27 has a shape in which the plasma discharge tube 26 is attached and protruded. The lower part of the plasma discharge tube 26 is electrically grounded and the lower part of the plasma discharge tube 26 is electrically isolated from the closing part of the first body 22. [ The reason for this is that it is preferable to first decompose the gas at the inlet of the gas to increase and decrease the decomposition efficiency. The magnetic core 28 is for generating a plasma discharge in the exhaust plasma reactor 14 and is mounted along the periphery of a plurality of plasma discharge tubes 26 configured to process a large amount of exhaust gas. The clamping portion (30) includes a plurality of magnetic cores (28).

The clamping portion 30 including the magnetic core 28 and the inlet support portion 24 for coupling the first and second bodies 22 and 27 are further included. The inlet support portion 24 is located below the first body 22. The process of joining the first and second bodies 22 and 27 through the inlet support part 24 is as follows. First, the clamping portion 30 including the magnetic core 28 is seated on the plasma discharge tube 26 of the second body 27. Next, the first body 22 is placed on the upper part and the inlet support part 24 is inserted to dock the first core 22 and the magnetic core 28 fastened by the clamping part 30. [ When the bolt is inserted and fastened on the docked first body 22, the clamping part 30 including the magnetic core 28 ascends to the inlet support 24 and is engaged with the first body 22. [

4 is a plan view of an exhaust plasma reactor including a plurality of plasma discharge tubes.

The diameter of the gas inlet 20 and the gas outlet (not shown) are the same as the diameter of the plasma discharge tube 26. When the number of plasma discharge tubes 26 is large, a diameter of a plurality of bores is equal to a diameter of a gas inlet 20 and a gas outlet (not shown). Therefore, irrespective of the number of the plasma discharge tubes 26 depending on the amount of exhaust gas treatment or the processing speed, the sum of the diameters thereof is the same for the diameters of the gas inlet 20 and the gas outlet (not shown). This is because the process chamber 10 and the exhaust plasma reactor 14 are connected to the same pump 16 so that the vacuum state is not changed due to the change of the flow rate due to the exhaust plasma reactor 14 during the process .

5 to 6 are views of a plasma reactor for exhaust including a steam injection hole.

There are two water lines used in the exhaust plasma reactor: a PCW (process cooling water) line for controlling the temperature at which the exhaust plasma reactor becomes higher during the reaction, and a vaporization line for supplying water vapor for exhaust gas decomposition. The water vapor supplied from the vaporizer (not shown) through the vaporization line 36 is sprayed into the vapor spray hole 34 and is decomposed and mixed with the process gas passing through the gas inlet 20. The principle of decomposition is similar to a conventional wet gas scrubber, and the gas dissociation energy is generated through the exhaust plasma reactor according to the present invention. As shown in the drawing, the water vapor jetting hole 34 is formed of a plurality of holes. The water jetting hole 34 is formed at one side and the other side of the gas inlet 20 so as to flow into the plasma discharge tube 26 in a balanced manner. The position of the water vapor jetting hole 24 may vary depending on the number of the plasma discharge tubes 26 or the size of the aperture. However, the water vapor introduced from the vaporizer through the vaporization line 36 is not linearly connected to the vapor injection hole 34. This causes the flow rate of the inflow gas to be slowed and bent in a '?' Shape as shown in FIG. 6 so that water vapor is uniformly sprayed into the plasma discharge tube 26, or at least one flow rate control period is provided.

Figs. 7 to 8 are diagrams showing ignition electrodes of a plasma reactor for exhaust.

As shown, the first body 22 includes an ignition electrode portion 40 for igniting the process by-product gas entering through the gas inlet 20 entering therein. The ignition electrode unit 40 may be electrically connected to one side and the other side of the gas inlet 20 in parallel so that ignition may occur even if a problem arises in ignition of one side or the other side. Although two ignition electrode portions 40 are shown in the figure, a plurality of electrodes are connected in parallel so as to always ignite the process by-product gas exhausted from the process chamber. All of the ignition electrode portions 40 may be turned on depending on the amount of the process by-product gas to be discharged or the conditions, thereby causing a plasma discharge. The ceiling portion connected to the plasma discharge tube (not shown) inside the first body 22 has a dome-shaped structure as shown in the figure. This is a structure in which the ignition electrode unit 40 can be positioned and the distribution efficiency is maximized so that the gas can be evenly distributed. Further, the ignition electrode portion 40 is connected to the tube 42 having an angle with the plasma discharge chamber. A hollow region 41 is included in the lower portion of the ignition electrode portion 40. The hollow region 41 allows the incoming gas to remain and the plasma to float at all times. The tube 42 may be formed with a straight line or an angle to control the flow of the fluid, and less particles may be formed to allow better gas ignition. In addition, a plurality of fine holes may be formed in the tube 42 to induce the above-described technical effect.

The ignition electrode (43) is installed on the top of the dielectric plate to transfer the electromotive force to the plasma discharge tube of the plasma chamber. The ignition electrode 43 may be made of aluminum, but it may be made of other alternative metal materials. The ignition electrode 43 may be connected to a power source for supplying power to the primary winding (not shown) or may be connected to a separate power source. The dielectric plate is divided into a first insulating plate (45) and a second insulating plate (47) and is installed in the open region of the plasma chamber. The first insulating plate 45 is in a flat shape and the second insulating plate 47 is arranged on both sides of the ignition electrode 43 for supporting the ignition electrode 43. As shown in Fig. First and second sealing members 53 and 55 are provided on the first and second insulating plates 45 and 47, respectively. The first sealing member 53 prevents the plasma gas from entering the ignition electrode 43 in the reactor body during the plasma discharge. It also prevents particles from being formed by the plasma backstreamed from the process chamber during the process. The second sealing member 55 prevents the plasma generated in the plasma discharge tube from flowing into the ignition electrode 43. The first and second sealing members 53 and 55 use O-rings.

9 is a view of a magnetic core assembly for an exhaust plasma reactor.

As shown, the magnetic core assembly includes a clamping portion 30 and a plurality of magnetic cores 28 constrained to the clamping portion 30. As shown in FIG. The clamping portion 30 has a shape to enclose a part of the magnetic core 28. When a plasma for processing the exhaust gas is formed in the exhaust plasma reactor, the temperature of the magnetic core 28 surrounding the plasma discharge tube and the plasma discharge tube is increased. Therefore, the clamping portion 30 is limited to the role of wrapping the plurality of magnetic cores 28, and in order to maximally prevent the temperature of the magnetic core 28 from rising due to the clamping portion 30, . The material of the clamping portion 30 is preferably aluminum or an aluminum alloy, and quartz or a dielectrical substance is all possible.

10 is a view showing a combination of magnetic cores.

The magnetic core 28 has a "C" shape and is configured to surround the plasma discharge tube by coupling the two. The magnetic core 28 in the shape of a " C " is divided into magnets again, as shown in the figure. The bar magnets are bonded to each other to constitute a magnetic core (28).

11 is a view showing a primary winding hole of a plasma reactor for exhaust.

A plurality of plasma discharge tubes 26 are formed in a rectangular tube-shaped cylindrical tube in a rectangular parallelepiped structure. Plasma is formed inside the plasma discharge tube 26, and the principle thereof is as follows. A magnetic core and a primary winding are mounted on the plasma discharge tube 26, though not shown, to transfer electromotive force for plasma generation. The primary winding is wound to pass through the primary winding hole 44 as shown in Fig. The primary winding is electrically connected to a power source that generates radio frequency. The current driven in the primary winding induces a current inside the plasma discharge tube 26 forming the toroidal remote inductively coupled plasma, and consequently the inside of the plasma discharge tube 26 becomes the secondary winding. The shape of the primary winding hole 44 may be modified depending on the number of times the primary winding is wound or electrically connected as shown in a triangular shape, a distorted triangle shape, a circular shape or a quadrilateral shape as shown in the drawing.

Figures 12-15 illustrate various embodiments in which the primary winding is wound.

The method of winding the primary winding 46 on the plasma discharge tube 26 may include a method of winding the secondary winding 46 one or more times along the primary winding holes 44 of the plurality of plasma discharge tubes 26 or a method of connecting them in series, A method of connecting the primary windings 46 to a plurality of power supply sources, a method of inserting a rectifying circuit so as to keep the power applied to each plasma discharge tube 26 uniformly after connecting in parallel And so on. As shown, the magnetic fields of the neighboring plasma discharge tubes 26 are opposite in direction.

It will be apparent to those skilled in the art that various modifications and equivalent arrangements may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, it is to be understood that the present invention is not limited to the above-described embodiments. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims. It is also to be understood that the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

10: process chamber 12: exhaust line
14: Plasma reactor for exhausting 16: Pump
18: scrubber 20: gas inlet
22: first body 24: inlet support part
26: plasma discharge tube 27: second body
28: magnetic core 30: clamping part
32: gas outlet 34: steam jet hole
36: vaporization line 40: ignition electrode part
42: gas pipe 43: ignition electrode
44: primary winding hole 45: first insulation plate
46: primary winding 47: second insulation plate
53: first sealing member 55: second sealing member

Claims (4)

An ignition electrode for transferring an electromotive force to the plasma discharge channel;
A hollow region located below the ignition electrode; And
And a tube connected to the hollow region and the plasma discharge channel and angled at an angle. The method according to claim 1,
Wherein the tube includes a plurality of porous holes therein. The method according to claim 1,
Wherein an ignition electrode portion is constituted by a lower portion of the ignition electrode. The method of claim 3,
Wherein the insulating plate is made of sapphire.

Images