KR102142867B1 - Atmospheric Pressure Plasma Generation Apparatus - Google Patents

Abstract

An atmospheric pressure plasma generating apparatus according to an embodiment of the present invention includes: a dielectric discharge tube; An initial discharge induction coil module including an initial discharge induction coil surrounding the dielectric cylindrical tube and having a plurality of windings to generate an atmospheric pressure initial discharge, and an initial discharge capacitor connected in series with the initial discharge induction coil to provide a first resonant frequency ; A first electrode and a second electrode respectively disposed above and below the initial discharge induction coil to provide an initial discharge seed; DC power supply for applying a DC high voltage between the first electrode and the second electrode; A main discharge induction coil module having a second resonance frequency and receiving an initial discharge generated by the initial discharge induction coil module to generate a main inductively coupled plasma; And an RF power supply for providing RF power to the initial discharge induction coil module and the main discharge induction coil module connected in parallel and changing a driving frequency.

Description

Atmospheric Pressure Plasma Generation Apparatus

The present invention relates to a plasma generating apparatus, and more particularly, to an inductively coupled plasma apparatus that performs discharge at atmospheric pressure or above atmospheric pressure.

Inductively coupled plasmas are typically formed using a drive frequency of several MHz at a pressure of several hundred milliTorr (mTorr). However, such an inductively coupled plasma has a small intensity of an induced electric field, making it difficult to perform atmospheric discharge or discharge at a pressure of several hundred torr or more. Therefore, sufficient intensity of the induced electric field is required and a separate means for initial discharge is required. Even if the atmospheric pressure discharge is maintained, the discharge cannot be performed for a long time due to thermal damage caused by ions from the plasma of the dielectric tube.

When inductively coupled plasma discharge is performed by applying RF power to an induction coil surrounding the dielectric tube, the inductively coupled plasma heats the dielectric tube, and the dielectric tube is heated and damaged. Therefore, the high-power inductively coupled plasma has a structural limitation.

The inventor of the present invention proposed a swirling flow (swirl) in order to maintain the stability of the plasma in Korean Patent Registration KR 10-1657303 B1. However, an antenna having a plurality of windings has a limitation in atmospheric pressure discharge as the induction electric field increases during discharge and the antenna voltage accelerates ions to the tube wall to cause thermal damage.

The inventors of the present invention proposed an inductively coupled plasma generating device having a voltage distribution structure by inserting a capacitor between antennas in Korean Patent Registration KR 0-1826883 B1. However, Korean Patent Registration KR 0-1826883 B1 induces initial discharge when the driving frequency is out of the resonance condition, but it is difficult to stably ignite the atmospheric pressure discharge due to the small intensity of the electric field.

One technical problem to be solved by the present invention is to provide a plasma generating apparatus that generates stable inductively coupled plasma at atmospheric pressure or a pressure of several hundred torr or more.

An atmospheric pressure plasma generating apparatus according to an embodiment of the present invention includes: a dielectric discharge tube; An initial discharge induction coil module including an initial discharge induction coil surrounding the dielectric cylindrical tube and having a plurality of windings to generate an atmospheric pressure initial discharge, and an initial discharge capacitor connected in series with the initial discharge induction coil to provide a first resonant frequency ; A first electrode and a second electrode respectively disposed above and below the initial discharge induction coil to provide an initial discharge seed; DC power supply for applying a DC high voltage between the first electrode and the second electrode; A main discharge induction coil module having a second resonance frequency and receiving an initial discharge generated by the initial discharge induction coil module to generate a main inductively coupled plasma; And an RF power supply for providing RF power to the initial discharge induction coil module and the main discharge induction coil module connected in parallel and changing a driving frequency. The main discharge induction coil module includes: a plurality of unit antennas disposed to be spaced apart from the initial discharge induction coil, disposed on a plurality of placement planes perpendicular to a central axis of the dielectric discharge tube, and connected in series with each other; A first main capacitor and a second main capacitor respectively disposed at both ends of the unit antennas; And auxiliary capacitors connected in series between the unit antennas, respectively. The RF power source induces an initial discharge in the initial discharge induction coil at the first resonant frequency with the help of the DC high voltage. The RF power performs main discharge by changing the driving frequency from the first resonance frequency to the second resonance frequency.

In one embodiment of the present invention, it further includes a first detection sensor for sensing a current or voltage flowing through the initial discharge induction coil. The RF power may sense a transition from a power storage coupling mode to an inductive coupling mode using the output of the first detection sensor and change a driving frequency from the first resonance frequency to the second resonance frequency.

In one embodiment of the present invention, the first electrode may be disposed above the initial discharge induction coil and charged with a positive DC high voltage. The second electrode is disposed under the initial discharge induction coil and has a "C" shape so as to surround the dielectric discharge tube, and may be charged with a negative DC high voltage.

In an embodiment of the present invention, the DC power supply includes: an AC-DC converter converting commercial power into a DC voltage; A high voltage pulse generator that receives the DC voltage and generates a positive DC high voltage pulse and a negative DC high voltage pulse; And a controller controlling the high voltage pulse generator.

In one embodiment of the present invention, the high voltage pulse generator includes: a first transformer including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a positive DC high voltage pulse; A first power transistor connected to the primary coil of the first transformer; A second transformer including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a negative DC high voltage pulse; And a second power transistor connected to the primary coil of the second transformer. The controller may control gates of the first power transistor and the second power transistor. One end of the secondary coil of the first transformer may output a positive DC high voltage pulse, and the other end of the secondary coil of the first transformer may be grounded. One end of the secondary coil of the second transformer may output a negative DC high voltage pulse, and the other end of the secondary coil of the second transformer may be grounded.

In one embodiment of the present invention, the initial discharge induction coil has a solenoid shape and may be wound in a double layer.

In one embodiment of the present invention, the initial discharge induction coil may have a three-layer structure of an internal solenoid coil, an intermediate solenoid coil, and an external solenoid coil.

In an embodiment of the present invention, the initial discharge capacitor may be disposed at both ends of the initial discharge induction coil.

In one embodiment of the present invention, the cross section of the coil constituting the unit antenna may be a square.

In one embodiment of the present invention, the unit antenna includes: a first antenna disposed in contact with the dielectric discharge tube in a plane perpendicular to a central axis of the dielectric discharge tube and forming a loop; A second antenna disposed to surround the first antenna and forming a loop; And a third antenna disposed to surround the second antenna and forming a loop.

In an embodiment of the present invention, the number of unit antennas may be 10 and are disposed on different placement planes.

In an embodiment of the present invention, the unit antennas may be divided into a first group including five unit antennas and a second group including other five unit antennas. The unit antennas constituting the first group may be disposed at 72° intervals along the azimuth direction, and the unit antennas constituting the second group may be disposed at 72° intervals along the azimuth direction.

In an embodiment of the present invention, the unit antenna may include a plurality of windings disposed on the same arrangement plane, and may further include an insulating spacer having a "W" shape to insulate the plurality of windings.

In an embodiment of the present invention, the first resonance frequency and the second resonance frequency may be separated by 0.2 MHz or more.

In an embodiment of the present invention, the first resonance frequency may be greater than the second resonance frequency.

In an embodiment of the present invention, the capacitance of the first main capacitor may be the same as that of the second main capacitor, and the capacitance of the first main capacitor may be twice the capacitance of the auxiliary capacitor. .

In an embodiment of the present invention, a first voltage drop induced in the initial discharge induction coil at the first resonance frequency may be greater than a second voltage drop induced in the unit antenna at the second resonance frequency.

In an embodiment of the present invention, the sum of the inductances of the plurality of unit antennas may be greater than the inductance of the initial discharge induction coil.

An operating method of an atmospheric pressure plasma generating apparatus according to an embodiment of the present invention includes the steps of applying a DC high voltage to a first electrode and a second electrode disposed to be spaced apart from each other in a dielectric discharge tube to provide an initial discharge seed; An initial discharge induction coil module including an initial discharge induction coil surrounding the dielectric cylindrical tube and having a plurality of windings to generate an atmospheric pressure initial discharge, and an initial discharge capacitor connected in series with the initial discharge induction coil to provide a first resonant frequency Performing initial discharge by providing AC power of the first resonance frequency to the device; And inducing a main inductively coupled plasma from the initial discharge by providing AC power having a second resonance frequency different from the first resonance frequency to a main discharge induction coil module connected in parallel with the initial discharge induction coil module.

In an embodiment of the present invention, the method further includes: sensing a current flowing through the initial discharge induction coil or a voltage drop applied to both ends of the initial discharge induction coil. When the current flowing through the initial discharge induction coil or the voltage drop applied to both ends of the initial discharge induction coil is greater than or equal to a threshold value, the RF power source changes the driving frequency from the first resonance frequency to the second resonance frequency. Main discharge may be performed in the unit antennas.

In one embodiment of the present invention, the main discharge induction coil module is disposed to be spaced apart from the initial discharge induction coil, the dielectric discharge tube is disposed on a plurality of placement planes perpendicular to a central axis, and connected in series with each other. A plurality of unit antennas; A first main capacitor and a second main capacitor respectively disposed at both ends of the unit antennas; And auxiliary capacitors connected in series between the unit antennas, respectively. The RF power may induce initial discharge in the initial discharge induction coil at the first resonance frequency with the help of the DC high voltage. The RF power may change the driving frequency from the first resonant frequency to the second resonant frequency to perform main discharge in the unit antennas.

Atmospheric pressure plasma generation apparatus according to an embodiment of the present invention performs stable plasma generation at atmospheric pressure or higher pressure using an electrode for seed generation, an initial discharge induction coil advantageous for ignition, and a main discharge induction coil module advantageous for discharging maintenance. can do.

1 is a conceptual diagram showing an application example of an atmospheric pressure plasma device according to an embodiment of the present invention.
2A is a conceptual diagram illustrating an initial discharge operation of an atmospheric pressure plasma device according to an embodiment of the present invention.
2B is a conceptual diagram illustrating a main discharge operation of an atmospheric pressure plasma device according to an embodiment of the present invention.
3 is a conceptual diagram showing the atmospheric pressure plasma device of FIG. 2A in a circuit diagram.
4 is a conceptual diagram showing voltage distribution applied to an initial discharge induction coil module in an initial discharge operation of the atmospheric pressure plasma apparatus of FIG. 2A.
5 is a conceptual diagram showing voltage distribution applied to the main discharge induction coil module in the main discharge operation of the atmospheric pressure plasma device of FIG. 2B.
6 is a plan view showing an arrangement relationship of unit antennas of a main discharge induction coil module according to an embodiment of the present invention.
7 is a plan view illustrating a unit antenna of the main discharge induction coil module according to an embodiment of the present invention.
8 is a cross-sectional view illustrating an insulation state of unit antennas of the main discharge induction coil module according to an embodiment of the present invention.
9 is a cut perspective view illustrating an arrangement relationship between a first electrode and a second electrode according to an exemplary embodiment of the present invention.
10 is a circuit diagram showing a DC power supply according to another embodiment of the present invention.
11 is a circuit diagram illustrating the high voltage pulse generator of FIG. 10.
12 is a cross-sectional view illustrating a main discharge induction coil module of an atmospheric pressure plasma generating apparatus according to another embodiment of the present invention.
13 is a plan view illustrating an arrangement relationship of unit antennas of the main discharge induction coil module of FIG. 12.
FIG. 14 is a diagram showing an equivalent circuit for explaining the initial discharge mode of the atmospheric pressure plasma generating device of FIG. 12;
FIG. 15 is a diagram showing an equivalent circuit for explaining the main discharge mode of the atmospheric pressure plasma generator of FIG. 12;
16 is a timing diagram showing an initial discharge mode and a main discharge mode of the atmospheric pressure plasma generator of FIG. 12.

A plasma generating device according to an embodiment of the present invention includes a pair of electrodes disposed on a dielectric discharge tube, an initial discharge induction coil module, and a main discharge induction coil module. The initial discharge induction coil module and the main discharge induction coil module are connected in parallel to the RF power supply, and the RF power supply selectively provides RF power to the initial discharge induction coil module or the main discharge induction coil module according to the resonance frequency.

The initial discharge module has an antenna that is advantageous for ignition, and the main discharge module has antenna characteristics that are advantageous for maintaining discharge. The initial discharge module and the main discharge module connected in parallel have different impedance characteristics according to the driving frequency. The initial discharge module has a first resonance frequency, and the main discharge module has a second resonance frequency. When the current flows at the first resonance frequency, the current mainly flows to the initial discharge module. A route other than resonance has a relatively large impedance at the first resonance frequency, so that a relatively small current flows. When the current flows at the second resonance frequency, the current mainly flows to the main discharge module. Even if there are three or more discharging modules, if different resonant frequencies are provided for each discharging module, current may be applied to a desired discharging module. Accordingly, the present invention can perform impedance matching in a wide range of actual resistance, can implement a wide discharge control range (flow rate, power, pressure), and change the discharge function by switching current to a discharge module for various purposes. have.

The pair of electrodes are disposed above and below the initial discharge induction coil of the initial discharge module, respectively, and apply a DC voltage at atmospheric pressure to perform the initial discharge in the direction of the central axis of the dielectric discharge tube (E_ig). And generate a seed charge.

The initial discharge induction coil module is disposed between the pair of electrodes and includes the initial discharge induction coil and an initial discharge capacitor connected in series with the initial discharge induction coil. The main discharge module and the initial discharge module are connected in parallel. The initial discharge induction coil module has a first resonant frequency and receives RF power of the first resonant frequency in an initial discharge mode from an RF power source to perform initial discharge. The main discharge module does not discharge due to a high impedance at the first resonance frequency. Plasma by the initial discharge induction coil transitions from the capacitive coupling mode (or E mode) to the inductive coupling mode (or H mode). In the capacitive coupling mode (or E mode), the initial discharge induction coil generates a high potential difference at both ends of the initial discharge induction coil at a first resonant frequency. A vertical electric field E_z may be generated in the direction of the central axis of the dielectric discharge tube. After transitioning to the inductive coupling mode (or H mode), the actual plasma resistance increases and the first current flowing through the initial discharge induction coil decreases.

The main discharging module includes unit antennas connected in series with each other disposed spaced apart from the initial discharging induction coil and disposed on a plurality of placement planes, respectively, a first main capacitor and a second main capacitor disposed at both ends of the unit antennas respectively ; And an auxiliary capacitor connected in series between the unit antennas. The main discharge module and the initial discharge module are connected in parallel. The main discharge module has a second resonant frequency. When transitioning from the capacitive coupling mode (or E mode) to the inductive coupling mode (or H mode) by the initial discharge induction coil, the RF power source changes the driving frequency from the first resonance frequency to the second resonance frequency. At the same time, the DC voltage is removed from the pair of electrodes. Accordingly, the initial discharge module does not perform discharge because current does not flow due to a high impedance, and the main discharge module stably generates an inductively coupled plasma through current flow due to a low impedance.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art. In the drawings, components are exaggerated for clarity. Parts denoted by the same reference numerals throughout the specification represent the same elements.

1 is a conceptual diagram showing an application example of an atmospheric pressure plasma device according to an embodiment of the present invention.

Referring to FIG. 1, a substrate processing apparatus 10 includes a substrate holder 93 in a vacuum container 92, and a deposition process, an etching process, and a substrate 94 disposed on the substrate holder 93 are provided. A diffusion process or an ion implantation process may be performed. The vacuum container 92 is evacuated by the vacuum pump 95, and the exhaust gas is purified through the atmospheric pressure plasma generating device 100 to be discharged to the outside. The exhaust gas contains pollutants such as fine particles, highly toxic gases, and greenhouse gases.

The exhaust gas is discharged after being purified through a gas scrubber. Gas scrubbers include combustion type or plasma type.

The atmospheric discharge plasma method may include a high voltage flat plate plasma method, an arc torch method, and an induction heating plasma method. In the case of a high voltage flat plate type plasma, it has a high discharge holding ability, but it is difficult to form a low plasma density and high temperature condition at a high operating pressure. Therefore, the effect of removing toxic substances by thermochemical decomposition is low.

On the other hand, a high-temperature plasma such as an arc torch provides a high reaction temperature, but since the processing gas is not directly injected into the plasma, the decomposition efficiency decreases, and the durability of the electrode for generating an arc is weak.

Atmospheric pressure plasma apparatus according to an embodiment of the present invention can implement a high plasma density (10^16/cm^3) and a high gas temperature (3000 degrees Celsius) by using inductively coupled plasma at a pressure of 100 Torr or more. Accordingly, the atmospheric pressure plasma device may be disposed at the rear end of the vacuum pump to decompose and treat harmful gas that is mixed with gas of several tens of slm (Standard liter per minute) or more under atmospheric pressure. The harmful gas may be CxFy or SxFy gas. In the present invention, it is possible to perform inductively coupled discharge at atmospheric pressure of CxFy gas, which is difficult to discharge at atmospheric pressure. The atmospheric pressure plasma apparatus according to an embodiment of the present invention may be used in processes such as CO2 reforming.

2A is a conceptual diagram illustrating an initial discharge operation of an atmospheric pressure plasma device according to an embodiment of the present invention.

2B is a conceptual diagram illustrating a main discharge operation of an atmospheric pressure plasma device according to an embodiment of the present invention.

3 is a conceptual diagram showing the atmospheric pressure plasma device of FIG. 2A in a circuit diagram.

4 is a conceptual diagram showing voltage distribution applied to an initial discharge induction coil module in an initial discharge operation of the atmospheric pressure plasma apparatus of FIG. 2A.

5 is a conceptual diagram showing a voltage distribution applied to a main discharge induction coil module in a main discharge operation of the atmospheric pressure plasma device of FIG. 2A.

6 is a plan view showing an arrangement relationship of unit antennas of a main discharge induction coil module according to an embodiment of the present invention.

7 is a plan view illustrating a unit antenna of the main discharge induction coil module according to an embodiment of the present invention.

8 is a cross-sectional view illustrating an insulation state of unit antennas of the main discharge induction coil module according to an embodiment of the present invention.

9 is a cut perspective view illustrating an arrangement relationship between a first electrode and a second electrode according to an exemplary embodiment of the present invention.

2 to 9, the atmospheric pressure plasma generating apparatus 100 includes a dielectric discharge tube 140; An initial discharge induction coil 120 that surrounds the dielectric cylindrical tube 140 and has a plurality of windings and generates an atmospheric pressure initial discharge and is connected in series with the initial discharge induction coil 120 to provide a first resonance frequency fa The initial discharge induction coil module 102 including the initial discharge capacitors (122a, 122b); A first electrode 114 and a second electrode 116 disposed above and below the initial discharge induction coil 120 to provide an initial discharge seed; A DC power supply (112) applying a DC high voltage between the first electrode (114) and the second electrode (116); A main discharge induction coil module 103 receiving an initial discharge generated by the initial discharge induction coil module 102 with a second resonance frequency fb to generate a main inductively coupled plasma; And an RF power supply 150 for providing RF power to the initial discharge induction coil module 102 and the main discharge induction coil module 103 connected in parallel and changing a driving frequency.

The main discharge induction coil module 103 is disposed to be spaced apart from the initial discharge induction coil 120 and disposed on a plurality of placement planes perpendicular to the central axis of the dielectric discharge tube 140 and connected in series with each other. A plurality of unit antennas 132; A first main capacitor (133a) and a second main capacitor (133b) disposed at both ends of the unit antennas 132, respectively; And auxiliary capacitors 134 connected in series between the unit antennas 132, respectively.

The RF power supply 150 induces an initial discharge in the initial discharge induction coil 120 at the first resonance frequency fa with the help of the DC high voltage. The RF power supply 150 performs main discharge by changing the driving frequency from the first resonance frequency fa to the second resonance frequency fb.

Atmospheric pressure inductively coupled plasma is difficult to generate ignition (or initial discharge) due to the low induced electric field. Therefore, for stable initial discharge, the DC discharge by the first electrode 114 and the second electrode 116 is assisted. On the other hand, DC discharge is difficult to form a high plasma density. An electrode disposed outside the dielectric discharge tube damages the dielectric discharge tube 140 by a high electric field E_ig.

The initial discharge induction coil 120 generates an initial inductively coupled plasma with the help of a seed charge by DC discharge. For this, a strong electrostatic vertical electric field E_z in the direction of the central axis of the dielectric discharge tube 140 is required. This strong electrostatic vertical electric field E_z depends on the structure of the initial discharge induction coil. The electrostatic vertical electric field E_z of the initial discharge induction coil 120 may generate a capacitive coupling mode. The electrostatic vertical electric field E_z may be generated by a high potential difference Va applied to both ends of the initial discharge induction coil. The electrostatic vertical electric field E_z may be proportional to the inductance La of the initial discharge induction coil 120. However, if the inductance La of the initial discharge induction coil 120 is too large, the power of the RF power supply 150 is not efficiently transferred to the load (initial discharge induction coil) due to high impedance. Accordingly, the initial discharge capacitors 122a and 122b are connected in series with the initial discharge induction coil 120 to provide a first resonant frequency fa. When the RF power supply 150 operates at the first resonance frequency, the imaginary part of the impedance Za viewed from the initial discharge induction coil 120 from the output terminal of the RF power source may be removed. Accordingly, the RF power supply 150 may stably transmit RF power to the initial discharge induction coil. In addition, since the initial discharge induction coil 120 has a high inductance, a high potential difference Va is induced at both ends of the initial discharge induction coil 120, and the electrostatic vertical electric field E_z generates a capacitive coupling mode. I can make it. In the capacitive coupling mode, streamer discharge is locally formed in the direction of the central axis of the dielectric discharge tube 140.

When plasma is sufficiently generated by the capacitive coupling mode, an induced electric field E_a_ind in an azimuth direction is generated by the first current Ia flowing through the initial discharge induction coil 120. Plasma transitions from the capacitive coupling mode to the inductive coupling mode by the induced electric field E_a_ind. In the inductive coupling mode by the initial discharge induction coil 120, plasma is entirely generated within the dielectric discharge tube 140. In the inductive coupling mode, a first current Ia flowing through the initial discharge induction coil and a potential difference Va applied to both ends of the initial discharge induction coil decrease compared to the capacitive coupling mode.

However, in the inductive coupling mode by the initial discharge induction coil 120, a high potential difference is still maintained at both ends of the initial discharge induction coil due to the high inductance La of the initial discharge induction coil 120. Therefore, a plasma sheath is formed between the plasma having a constant plasma potential and the initial discharge induction coil 120, and ions pass through the plasma sheath, and the dielectric discharge tube ( 120) is accelerated to the inner wall. Accordingly, the dielectric discharge tube 120 is damaged by heat and discharge efficiency is reduced.

In the present invention, in order to overcome this problem, an initial discharge induction coil 120 optimized for initial discharge and a main discharge induction coil module 103 that suppresses thermal damage of the dielectric discharge tube and increases discharge efficiency are used. In the initial discharging stage, RF power is introduced into the initial discharging induction coil 120 to cause a transition from the capacitive coupling mode to the inductive coupling mode. The main discharge induction coil module 103 uses a large amount of charged particles generated by the initial discharge induction coil 120 to directly generate plasma in the inductive coupling mode without going through the capacitive coupling mode.

The main discharge induction coil module 103 has electrical characteristics and discharge characteristics different from those of the initial discharge induction coil module 102. The main discharge induction coil module 103 includes a plurality of unit antennas 132 constituting the main discharge induction coil module. The antennas 132 are disposed on different placement planes, stacked on each other, and disposed to surround the dielectric discharge tube.

The main discharge induction coil module 103 is difficult to operate alone without the initial discharge induction coil. However, after the initial discharge induction coil transitions to the inductive coupling mode, the first current Ia flowing through the initial discharge induction coil 120 is removed, and a second current in the main discharge induction coil module 103 (Ib) flows. The main discharge induction coil module 103 can stably discharge in the inductive coupling mode immediately without going through the capacitive coupling mode. The second potential difference Vb applied to each of the unit antennas 132 is smaller than the potential difference Va applied to both ends of the initial discharge induction coil 120 by voltage distribution. The sum Lb of the inductances of the unit antennas 132 is greater than the inductance La of the initial discharge induction coil 120. Accordingly, the intensity of the induced electric field E_b_ind is large, the potential difference of the plasma sheath is small, thermal breakage of the dielectric discharge tube 140 is suppressed, and discharge efficiency is increased.

The main discharge induction coil module 103 is arranged to be spaced apart from the initial discharge induction coil, the dielectric discharge tube 140 is disposed on a plurality of arrangement planes perpendicular to a central axis, and a plurality of units connected in series with each other Antennas 132; A first main capacitor (133a) and a second main capacitor (133b) disposed at both ends of the unit antennas; And auxiliary capacitors 134 connected in series between the unit antennas, respectively. The main discharge induction coil module 103 has a second resonant frequency fb and performs voltage distribution in proportion to the number of the unit antennas 132. Accordingly, thermal damage to the dielectric discharge tube is suppressed, and discharge efficiency is increased.

The RF power supply 150 may change a driving frequency and selectively supply RF power to the initial discharge induction coil module 102 and the main discharge induction coil module 103 connected in parallel with each other. At the first resonant frequency fa, the RF power supply 150 mainly supplies power to the initial discharge induction coil module 102. Meanwhile, at the second resonant frequency fb, the RF power supply 150 mainly supplies power to the main discharge induction coil module 103.

The dielectric discharge tube 140 may be a cylindrical dielectric discharge tube. Specifically, the material of the dielectric discharge tube 140 may be ceramic, sapphire, or quartz. The ceramic may be alumina or AlN. The outer diameter of the dielectric discharge tube 140 may be several centimeters to tens of centimeters. The inner diameter of the dielectric discharge tube 140 may be several to tens of mm smaller than the outer diameter. The length of the dielectric discharge tube 140 may be several centimeters to several meters. Both ends of the dielectric discharge tube 140 may be sealed by coupling with the upper flange 142 and the lower flange 144, respectively. The lower flange 144 may receive the exhaust gas of the substrate processing apparatus 10 as a process gas.

Referring to FIG. 9, the initial discharge induction coil 120 may maximize the number of windings per unit length in the length direction of the dielectric discharge tube 120. The initial discharge induction coil 120 may be a solenoid coil having a multilayer structure. Specifically, the initial discharge induction coil 120 has a solenoid shape and may be wound in a double layer. The initial discharge induction coil 120 may have a three-layer structure of an inner solenoid coil 120a, an intermediate solenoid coil 120b, and an outer solenoid coil 120c. The inner solenoid coil 120a may be 4 turns surrounding the dielectric discharge tube. The intermediate solenoid coil 120b may be 4 turns surrounding the inner solenoid coil. The outer solenoid coil 120c may be three turns surrounding the intermediate solenoid coil 120b. The initial discharge induction coil 120 may be wound to constructively interfere with a magnetic field therein. For example, the inductance La of the initial discharge induction coil 120 may be 8uH. The initial discharge induction coil 120 may be formed of a copper pipe, and a refrigerant may flow inside the initial discharge induction coil. The cross section of the pipe constituting the initial discharge induction coil may be circular.

The initial discharge capacitors 122a and 122b may be connected to at least one of both ends of the initial discharge induction coil. The initial discharge capacitors 122a and 122b and the initial discharge induction coil 120 may be connected in series to provide a first resonant frequency fa. The capacitance Ca of the first initial discharge capacitor 122a may be the same as the capacitance Ca of the second initial discharge capacitor 122b.

The first resonance frequency fa may be 3.3 MHz. The first resonant frequency fa may be defined by an equivalent capacitance C'a of the initial discharge capacitors 122a and 122b and an inductance La of the initial discharge induction coil 120. The initial discharge capacitors 122a and 122b may be disposed at one of both ends of the initial discharge induction coil.

The DC power source 112 may generate a high voltage DC pulse. The high voltage DC pulse may be a negative DC high voltage and a positive DC high voltage. The DC power source 112 may generate a high voltage pulse of several tens of kHz. The negative DC high voltage may be a negative tens of kV, and the positive DC high voltage may be a positive tens of kV.

The pair of electrodes 114 and 116 includes a first electrode 114 and a second electrode 116 disposed above and below the initial discharge induction coil 120, respectively. The first electrode 114 may be charged with a positive DC high voltage and may be in the form of a square plate that is in close contact with and attached to a dielectric discharge tube.

The first electrode 114 is disposed above the initial discharge induction coil 120 in contact with the outer wall of the dielectric discharge tube 140 and receives the positive DC high voltage. The first electrode 114 may have a rectangular shape.

The second electrode 116 is disposed under the initial discharge induction coil 120 in contact with the outer wall of the dielectric discharge tube 120 and receives the negative DC high voltage. The second electrode 116 may have a "C" shape to surround the dielectric discharge tube. The second electrode may have a larger area than the first electrode so as to generate electrons. The second electrode 116 may be disposed to surround the dielectric discharge tube with a strip-shaped conductor. The second electrode 116 may be heated by an induction electric field E_a_ind by the initial discharge induction coil or an induction electric field E_b_ind by the unit antennas. Therefore, it is possible to have a "C" shape without forming a perfect loop so that eddy current due to the induced electric fields E_a_ind and E_b_ind does not flow. The second electrode may be charged with a negative DC high voltage and may be in the form of a band attached in close contact with the dielectric discharge tube. In addition, the second electrode may be formed to be serpentine so that the induced electric field in the azimuth direction does not flow, or may include a plurality of slits extending in the direction of the central axis of the cylinder.

Voltages applied to the first electrode 114 and the second electrode 116 have opposite signs and may have the same absolute value. The DC power supply 112 applying a DC high voltage to the first electrode 114 and the second electrode 116 may apply a level of 30 kV at atmospheric pressure. In this case, a vertical streamer and a "C" shape on the second electrode 116 in a vertical direction connecting the first electrode 114 and the second electrode 116 (direction of the central axis of the dielectric discharge tube) Of the streamer. When the second electrode 116 forms a perfect loop, the first current flowing through the initial discharge induction coil 120 may generate a eddy current in the second electrode 116 and heat it. Therefore, to suppress the eddy current, the second electrode 116 may be cut while securing a sufficient area or may have a slit in a vertical direction.

The interval between the first electrode 114 and the initial discharge induction coil 120 or the interval between the second electrode 116 and the initial discharge induction coil 120 is a parasitic discharge and an induced electric field by a high voltage at atmospheric pressure. It can be sufficiently spaced so as to suppress the induction heating by. Specifically, a distance between the first electrode 114 and the initial discharge induction coil 120 or a distance between the second electrode 116 and the initial discharge induction coil 120 may be several cm or more. Preferably, the interval may be 1 cm or more.

The RF power supply 150 may output RF power. The RF power supply 150 may convert commercial AC power into RF power and transmit it to a load. For example, the RF power may have a frequency of several hundred kHz to several tens of MHz and power of several tens of kW or more. The RF power supply 150 may include a rectifier, an inverter, and a controller. The rectifier may convert commercial AC power into DC power. The inverter may receive the DC power and convert it into RF power in response to switching signals from the controller. The controller can control the driving frequency and power by controlling the switching signals. The RF power may perform impedance matching at a first resonance frequency fa or a second resonance frequency fb by changing a driving frequency. The first resonance frequency fa and the second resonance frequency fb may be separated from each other by 0.2 MHz or more. When the first resonant frequency fa is within 0.2 MHz of the second resonant frequency fb, the impedances of the two current directions are similar, so that power switching may be unstable. The first resonance frequency fa may be greater than the second resonance frequency fb.

The first detection sensor 152 may sense a current or voltage flowing through the initial discharge induction coil 120. The second detection sensor 154 may sense a current or voltage flowing through the main discharge induction coil module 103. The RF power supply 150 may detect a transition from a capacitive coupling mode to an inductive coupling mode using an output of the first detection sensor 152 and change a driving frequency from the first resonant frequency to the second resonant frequency. .

6, the main discharge induction coil module 103 includes a plurality of unit antennas, auxiliary capacitors 134 respectively disposed between the plurality of unit antennas 132, and all of the plurality of unit antennas. It includes a first main capacitor (133a) and a second main capacitor (133b) disposed at both ends of the. The cross section of the coil constituting the unit antenna 132 may be rectangular. The unit antennas 132 may be arranged at intervals of 90 degrees in the clockwise direction. Accordingly, terminals electrically connecting the unit antennas 132 may not interfere with each other.

Referring to FIGS. 7 and 8, the rectangular cross section increases the contact area with the dielectric discharge tube 140 to improve heat exchange efficiency, thereby cooling the dielectric discharge tube 140. In the case of performing the main discharge, plasma may transfer energy to the dielectric discharge tube 140 and heat it to several hundred degrees Celsius or more. The increase in temperature of the dielectric discharge tube 140 may cause material modification or damage. The unit antenna 132 is cooled by flowing a refrigerant therein. The coil having a circular cross section is in line contact with the dielectric discharge tube 140, and it is difficult to efficiently cool the dielectric discharge tube 140. Meanwhile, the cooling efficiency of the coil having a rectangular cross section increases through surface contact with the dielectric discharge tube 140. In order to stably maintain contact with the inner coil of the unit antenna 132 and the dielectric discharge tube 140, the inner coil is tightened to decrease the radius. Experimentally, in the case of a circular cross-section coil, breakage of the dielectric discharge tube 140 was found at an RF power of 5 kW or more. However, in the case of a rectangular cross-section coil, no breakage of the dielectric discharge tube 140 was found even at 8 kW.

The unit antenna 132 includes: a first antenna (132a) disposed in contact with the dielectric discharge tube 140 in a plane perpendicular to a central axis of the dielectric discharge tube and forming a loop; A second antenna (132b) continuously connected to the first antenna (132a), disposed to surround the first antenna, and forming a loop; And a third antenna 132c continuously connected to the second antenna 132b and disposed to surround the second antenna and forming a loop.

The unit antenna 132 has a square cross section, and the first antenna 132a is in close contact with the dielectric discharge tube to cool the dielectric discharge tube. The first antenna 132a and the second antenna 132b may be connected by a “U”-shaped first connector 32a. The second antenna 132b and the third antenna 132c may be connected by a second connector 32b having a “U” shape.

In order to contact the first antenna 132a with the dielectric discharge tube 140, clamps 35 may be disposed to make both ends of the first antenna 132a in close contact with each other. The clamp 35 may be a cable tie.

The unit antenna 132 includes a plurality of windings disposed on the same arrangement plane, and the insulating spacer 36 insulates the plurality of windings and may have a "W" shape. Each winding constituting the unit antenna 132 is electrically insulated by an insulating spacer 36 and may maintain a constant interval. The insulating spacer 36 may insulate between neighboring unit antennas 132. The insulating spacer may have a shape of "ㅛ", and the second antenna 132b may be inserted into the recessed portion 36a.

At least a portion of the first antenna 132a may be molded using a ceramic paste. The ceramic mold 37 surrounding at least a portion of the first antenna 132a may thermally contact the dielectric discharge tube. Accordingly, when a refrigerant flows through the unit antenna, the cooled unit antenna may cool the ceramic mold 37, and the ceramic mold 37 may indirectly cool the dielectric discharge tube 140.

The electrostatic capacity 2C1 of the first main capacitor 133a is the same as that of the second main capacitor 133b, and the electrostatic capacity of the first main capacitor 133a is the electrostatic capacity of the auxiliary capacitor 134 It may be twice the capacity (C1).

The second resonant frequency fb may be given by the sum Lb of the inductances of the plurality of unit antennas and the equivalent capacitance C'b of the capacitors 133a, 133b, and 134.

The first voltage drop Va induced to the initial discharge induction coil 120 at the first resonance frequency fa is a second voltage drop Vb induced to the unit antenna at the second resonance frequency fb Can be greater than The second voltage drop (Vb) is the second resonant frequency (fb) and the second current (Ib). And the product of the inductance L1 of the unit antenna. The first voltage drop Va is a first resonant frequency fa and a first current Ia. And the inductance La of the initial discharge induction coil.

The sum Lb of inductances of the plurality of unit antennas may be greater than the inductance La of the initial discharge induction coil.

10 is a circuit diagram showing a DC power supply according to another embodiment of the present invention.

11 is a circuit diagram illustrating the high voltage pulse generator of FIG. 10.

Referring to FIGS. 10 and 11, the DC power supply 112 includes an AC-DC converter 1120 for converting commercial power into a DC voltage Vin; A high voltage pulse generator 1122 for receiving the DC voltage Vin and generating a positive DC high voltage pulse and a negative DC high voltage pulse; And a controller 1124 controlling the high voltage pulse generator.

The high voltage pulse generator 1122 includes a first transformer 1222a including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a positive DC high voltage pulse; A first power transistor (1222b) connected to the primary coil of the first transformer; A second transformer (1222c) including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a negative DC high voltage pulse; And a second power transistor 1222d connected to the primary coil of the second transformer. The controller 1124 controls gates of the first power transistor 1222b and the second power transistor 1222d. One end of the secondary coil of the first transformer 1222a outputs a positive DC high voltage pulse, and the other end of the secondary coil of the first transformer 1222a is grounded. One end of the secondary coil of the second transformer 1222c outputs a negative DC high voltage pulse, and the other end of the secondary coil of the second transformer 1222c is grounded.

The DC voltage Vin may be a 12V ~ 24V DC voltage. The controller 1124 synchronizes and controls the on time and repetition frequency of the first power transistor 1222b and the second power transistor 1122d. The DC high voltage pulse may be several tens of kV, and the repetition frequency may be several tens of kHz.

12 is a cross-sectional view illustrating a main discharge induction coil module of an atmospheric pressure plasma generating apparatus according to another embodiment of the present invention.

13 is a plan view illustrating an arrangement relationship of unit antennas of the main discharge induction coil module of FIG. 12.

FIG. 14 is a diagram showing an equivalent circuit for explaining the initial discharge mode of the atmospheric pressure plasma generating device of FIG. 12;

FIG. 15 is a diagram showing an equivalent circuit for explaining the main discharge mode of the atmospheric pressure plasma generator of FIG. 12;

16 is a timing diagram showing an initial discharge mode and a main discharge mode of the atmospheric pressure plasma generator of FIG. 12.

12 to 16, the atmospheric pressure plasma generating apparatus 200 includes a dielectric discharge tube 140; An initial discharge induction coil 120 that surrounds the dielectric cylindrical tube 140 and has a plurality of windings and generates an atmospheric pressure initial discharge and is connected in series with the initial discharge induction coil 120 to provide a first resonance frequency fa The initial discharge induction coil module 102 including the initial discharge capacitors (122a, 122b); A first electrode 114 and a second electrode 116 disposed above and below the initial discharge induction coil 120 to provide an initial discharge seed; A DC power supply (112) applying a DC high voltage between the first electrode (114) and the second electrode (116); A main discharge induction coil module 203 for generating a main inductively coupled plasma by receiving an initial discharge generated by the initial discharge induction coil module 102 with a second resonance frequency fb; And an RF power supply 150 for providing RF power to the initial discharge induction coil module 102 and the main discharge induction coil module 203 connected in parallel and changing a driving frequency.

The main discharge induction coil module 203 is disposed to be spaced apart from the initial discharge induction coil 120 and disposed on a plurality of placement planes perpendicular to the central axis of the dielectric discharge tube 140 and connected in series with each other. A plurality of unit antennas 232a to 232d; 332a to 332e; First main capacitors 133a and second main capacitors 133b respectively disposed at both ends of the unit antennas 232a to 232d; 332a to 332e; And auxiliary capacitors 134 connected in series between the unit antennas 232a to 232d; 332a to 332e, respectively.

The RF power supply 150 induces an initial discharge in the initial discharge induction coil 120 at the first resonance frequency fa with the help of the DC high voltage. The RF power supply 150 performs main discharge by changing the driving frequency from the first resonance frequency fa to the second resonance frequency fb.

The unit antennas 232a to 232d; 332a to 332e are disposed on different placement planes and may be ten. The unit antennas 232a to 232d; 332a to 332e are divided into a first group 232a to 232d including five unit antennas and a second group 332a to 332e including other five unit antennas. The unit antennas constituting the first groups 232a to 232d may be disposed at 72 degree intervals along the azimuth direction. The unit antennas constituting the second groups 332a to 332e may be disposed at 72 degree intervals along the azimuth direction. Accordingly, the unit antennas may not interfere with each other for electrical connection of adjacent unit antennas.

Specifically, the equivalent capacitance (C'a) of the initial discharge capacitors 122a, 122b is 260pF, the inductance (La) of the initial discharge induction coil is 8uH, and the parasitic resistance (Ra) of the initial discharge induction coil May be 0.5 ohm. The first resonant frequency fa may be 3.3 MHz.

The inductance of the unit antenna may be 3.5 uH, and the sum of the inductances of the unit antenna may be 35 uH. In addition, the equivalent capacitance C'b of the capacitors 133a, 133b, and 134 constituting the main discharge induction coil module 203 may be 156 pF. The parasitic resistance Rb of the main discharge induction coil module 203 may be 2.1 ohms. The second resonance frequency fb may be 2.2 MHz.

Referring to FIG. 14, in the initial discharging step, the driving frequency may be 3.3 MHz, which is the first resonance frequency. In this case, the first current Ia flowing through the initial discharge induction coil module 102 is 31.5A, and the second current Ib flowing through the main discharge induction coil module 203 is 0.04 A. Accordingly, the current ratio (Ia: Ib) or the impedance ratio may be 800:1. That is, in the initial discharging step, all currents flow to the initial discharging induction coil module 102 and may transition from the capacitive coupling mode to the inductive coupling mode. When the first current (Ia) or voltage flowing through the initial discharge induction coil module 102 is sensed and transitioned to the inductive coupling mode, the RF power changes the driving frequency to the second resonance frequency (fb) according to the control signal. do.

Referring to FIG. 15, in the main discharge step, the driving frequency may be 2 or 2 MHz, which are the second resonance frequencies. In this case, the first current Ia flowing through the initial discharge induction coil module 102 is 0.5A, and the second current Ib flowing through the main discharge induction coil module 203 is 49.5 A. Accordingly, the current ratio (Ia: Ib) or the impedance ratio may be 1:100. That is, in the main discharging step, all current flows to the main discharging induction coil module 203. Thus, a stable plasma is maintained.

In addition, the maximum value (Vo) of the potential difference (Va) applied to both ends of the initial discharging induction coil in the initial discharging step is about the maximum value (V2) of the potential difference (Vb) applied to both ends of the unit antenna in the main discharging step 5.2 times bigger Thus, thermal damage to the dielectric discharge tube can be eliminated.

In the above, the present invention has been illustrated and described with respect to specific preferred embodiments, but the present invention is not limited to these embodiments, and the present invention claimed in the claims by a person of ordinary skill in the technical field to which the present invention pertains. It includes all various types of embodiments that can be implemented within the scope not departing from the technical idea.

102: initial discharge induction coil module
103: main discharge induction coil module
120: initial discharge induction coil
132: unit antenna

Claims (21)

Dielectric discharge tube;
An initial discharge induction coil module including an initial discharge induction coil that surrounds the dielectric discharge tube and has a plurality of windings and generates an atmospheric pressure initial discharge, and an initial discharge capacitor connected in series with the initial discharge induction coil to provide a first resonance frequency ;
A first electrode and a second electrode respectively disposed above and below the initial discharge induction coil to provide an initial discharge seed;
DC power supply for applying a DC high voltage between the first electrode and the second electrode;
A main discharge induction coil module having a second resonance frequency and receiving an initial discharge generated by the initial discharge induction coil module to generate a main inductively coupled plasma; And
Including an RF power supply for providing RF power to the initial discharge induction coil module and the main discharge induction coil module connected in parallel and changing a driving frequency,
The main discharge induction coil module is:
A plurality of unit antennas disposed to be spaced apart from the initial discharge induction coil, disposed on a plurality of placement planes perpendicular to a central axis of the dielectric discharge tube, and connected in series with each other;
A first main capacitor and a second main capacitor respectively disposed at both ends of the unit antennas; And
Including; auxiliary capacitors each connected in series between the unit antennas,
The RF power induces an initial discharge in the initial discharge induction coil at the first resonance frequency with the help of the DC high voltage,
The RF power performs main discharge by changing the driving frequency from the first resonance frequency to the second resonance frequency,
Wherein the main discharge module does not discharge due to a high impedance at the first resonance frequency. According to claim 1,
Further comprising a first detection sensor for sensing a current or voltage flowing through the initial discharge induction coil,
The RF power source detects a transition from the capacitive coupling mode to the inductive coupling mode using the output of the first detection sensor and changes a driving frequency from the first resonance frequency to the second resonance frequency. Device. According to claim 1,
The first electrode is disposed above the initial discharge induction coil and charged with a positive DC high voltage,
The second electrode is disposed under the initial discharge induction coil and has a "C" shape to surround the dielectric discharge tube and is charged with a negative DC high voltage. According to claim 1,
The DC power source is:
AC-DC converter for converting commercial power into DC voltage;
A high voltage pulse generator that receives the DC voltage and generates a positive DC high voltage pulse and a negative DC high voltage pulse; And
Atmospheric pressure plasma generating apparatus comprising a controller for controlling the high voltage pulse generator. The method of claim 4,
The high voltage pulse generator is:
A first transformer including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a positive DC high voltage pulse;
A first power transistor connected to the primary coil of the first transformer;
A second transformer including a primary coil receiving the DC voltage of the AC-DC converter and a secondary coil generating a negative DC high voltage pulse; And
Including a second power transistor connected to the primary coil of the second transformer,
The controller controls gates of the first power transistor and the second power transistor,
One end of the secondary coil of the first transformer outputs a positive DC high voltage pulse, and the other end of the secondary coil of the first transformer is grounded,
One end of the secondary coil of the second transformer outputs a negative DC high voltage pulse, and the other end of the secondary coil of the second transformer is grounded. According to claim 1,
The initial discharge induction coil is a solenoid type, atmospheric pressure plasma generating apparatus, characterized in that the winding in a double layer. According to claim 1,
The initial discharge induction coil has a three-layer structure of an internal solenoid coil, an intermediate solenoid coil, and an external solenoid coil. According to claim 1,
The initial discharge capacitor is an atmospheric pressure plasma generating apparatus, characterized in that disposed at both ends of the initial discharge induction coil. According to claim 1,
Atmospheric pressure plasma generator, characterized in that the cross section of the coil constituting the unit antenna is a square. The method of claim 9,
The unit antenna is:
A first antenna disposed in contact with the dielectric discharge tube in an arrangement plane perpendicular to a central axis of the dielectric discharge tube and forming a loop;
A second antenna disposed to surround the first antenna and forming a loop; And
And a third antenna disposed to surround the second antenna and forming a loop. The method of claim 9,
Atmospheric pressure plasma generating apparatus, characterized in that the unit antennas are 10 arranged on different placement planes. The method of claim 11,
The unit antennas are divided into a first group including five unit antennas and a second group including other five unit antennas,
The unit antennas constituting the first group are arranged at 72 degree intervals along an azimuth direction,
The unit antennas constituting the second group are arranged at 72 degree intervals along an azimuth direction. The method of claim 9,
The unit antenna includes a plurality of windings disposed on the same arrangement plane, and further includes an insulating spacer having a "W" shape to insulate the plurality of windings. According to claim 1,
The atmospheric pressure plasma generating apparatus, characterized in that the first resonance frequency and the second resonance frequency is spaced apart 0.2 MHz or more. According to claim 1,
The atmospheric pressure plasma generating apparatus, wherein the first resonant frequency is greater than the second resonant frequency. According to claim 1,
The capacitance of the first main capacitor is the same as that of the second main capacitor,
Atmospheric pressure plasma generating apparatus, characterized in that the electrostatic capacity of the first main capacitor is twice the electrostatic capacity of the auxiliary capacitor. According to claim 1,
The atmospheric pressure plasma generating apparatus, wherein a first voltage drop induced to the initial discharge induction coil at the first resonance frequency is greater than a second voltage drop induced to the unit antenna at the second resonance frequency. According to claim 1,
The atmospheric pressure plasma generating apparatus, wherein the sum of the inductances of the plurality of unit antennas is greater than the inductance of the initial discharge induction coil. Providing an initial discharge seed by applying a DC high voltage to the first electrode and the second electrode disposed to be spaced apart from each other in the dielectric discharge tube;
An initial discharge induction coil module including an initial discharge induction coil that surrounds the dielectric discharge tube and has a plurality of windings and generates an atmospheric pressure initial discharge, and an initial discharge capacitor connected in series with the initial discharge induction coil to provide a first resonance frequency Performing initial discharge by providing AC power of the first resonance frequency to the device;
Inducing a main inductively coupled plasma from the initial discharge by providing AC power having a second resonance frequency different from the first resonance frequency to a main discharge induction coil module connected in parallel with the initial discharge induction coil module; and
And the main discharge module does not perform discharge due to a high impedance at the first resonance frequency. The method of claim 19,
Sensing a current flowing through the initial discharge induction coil or a voltage drop applied to both ends of the initial discharge induction coil; further comprising,
When the current flowing through the initial discharge induction coil or the voltage drop applied to both ends of the initial discharge induction coil is greater than or equal to a threshold value, the RF power source changes the driving frequency from the first resonance frequency to the second resonance frequency, A method of operating an atmospheric pressure plasma generating apparatus, characterized in that the main discharge induction coil module performs main discharge. The method of claim 19,
The main discharge induction coil module is:
A plurality of unit antennas disposed to be spaced apart from the initial discharge induction coil, disposed on a plurality of placement planes perpendicular to a central axis of the dielectric discharge tube, and connected in series to each other;
A first main capacitor and a second main capacitor respectively disposed at both ends of the unit antennas; And
Including; auxiliary capacitors respectively connected in series between the unit antennas,
RF power induces an initial discharge in the initial discharge induction coil at the first resonant frequency with the help of the DC high voltage,
The operating method of the atmospheric pressure plasma generating apparatus, wherein the RF power changes a driving frequency and changes from the first resonant frequency to the second resonant frequency to perform main discharge in the unit antennas.

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