KR100572858B1 - Atmospheric pressure bulk plasma generator - Google Patents

Abstract

In the present invention, since the gas activated in a high energy state while passing through the discharge gap is used to form a glow plasma with a large amount of large area without leakage to the outside, a large atmospheric pressure area with high energy efficiency and improved processing speed of the workpiece. It relates to a glow plasma generator.

According to the present invention, in the apparatus for generating a glow plasma at atmospheric pressure by supplying a high-frequency power source 25, it is composed of a pair of members, one side member is grounded and the other member is a ground electrode connected to the high frequency power source 25 10 and the power source electrode 20, the dielectric material 31 provided between the ground electrode 10 and the power source electrode 20, and the ground electrode 10 or the power source electrode so as to be spaced apart from the dielectric material 31 by a predetermined distance. The workpiece transfer path 19 which is concave in the center portion of the workpiece 20 to form a closed passage, and at least one side of the workpiece transfer path 19 is narrower than the workpiece transfer path 19. A large atmospheric pressure plasma generating device comprising a discharge gap 17 formed at a distance from the dielectric 31 and a gas inflow path 11 formed to communicate with the discharge gap 17. Is provided.

Description

Atmospheric pressure bulk plasma generator

1 is a block diagram of a conventional atmospheric plasma generator

Figure 2 is an exploded perspective view showing an embodiment of the present invention

Figure 3 is a cross-sectional view of one embodiment of the present invention

<Description of the symbols for the main parts of the drawings>

10: ground electrode 11: gas inlet path

15: depression 17: discharge gap

19: transfer path of the workpiece 20: power pole

25: power

The present invention relates to an atmospheric pressure large area glow plasma generating apparatus, and more particularly, because the gas activated in a high energy state while passing through the discharge gap is used to form a large-area glow plasma without leakage to the outside, The high pressure, large-area glow plasma generator is to improve the processing speed of the workpiece.

In general, the technology for stably generating low-temperature plasma at atmospheric pressure has a wide range of applications ranging from surface treatment of various materials, cleaning operations, removal of toxic substances, and sterilization to advanced materials, electronics, and the environment.

The atmospheric plasma is roughly classified into a low frequency method of 100 kHz or less, a medium frequency method of 100 kHz to 2 MHz, and a high frequency method of 2 MHz to 60 MHz according to the applied frequency. Among them, the low frequency or the medium frequency method can easily generate plasma in a large area, but it is difficult due to safety problems due to high voltage, reduction of treatment efficiency due to low current, generation of ozone, and stable glow plasma. There are several problems, such as the need for a large amount of inert gas supply.

On the other hand, since the high frequency method maintains the plasma at a low voltage, the current flows up to 10 to 100 times compared to the low frequency method, and the plasma density is very high, thereby improving the surface treatment and cleaning effect.

A representative example of such a high-frequency atmospheric plasma generator is shown in FIG. 1. The atmospheric pressure plasma generator is composed of a pair of members which are spaced apart by a predetermined interval, the ground member 10 and the power pole 20 and the one side is grounded and the other member is connected to the high frequency power source 25, and the power supply pole ( 20 and a pair of dielectric films 35 respectively provided on the inner surface of the ground electrode 10 and between the dielectric film 35 and opened downward between the power supply electrode 20 and the ground electrode 10. Intermediate dielectric 30 to form a discharge gap 31, a gas inlet path 11 formed inside the ground electrode 10, the gas inlet path 11 and the discharge gap 31 is introduced in communication It consists of a plurality of gas discharge orifices 13 to be supplied to the discharge gap 31 evenly.

Therefore, in the atmospheric plasma generator, when the high frequency power source 25 is applied to the power source electrode 20, an electric field is formed in the discharge gap 31 between the power source electrode 20 and the ground electrode 10, and the gas flow path ( The gas flowing into the discharge gap 31 through 11) is dissociated by the electric field and is activated in a high energy state to generate plasma.

However, the gas activated in the high energy state is distributed between the workpiece 40 and the power electrode 20 or between the workpiece 40 and the ground electrode 10, and thus, the workpiece 40 and The gas flowing between the power source electrode 20 receives energy from the power source electrode 20 to maintain a continuous glow plasma, but the gas flowing between the workpiece 40 and the ground electrode 10 cuts off the energy supply, thereby maintaining a plasma. As a result, there is a problem that the resultant activated gas cannot be used for the treatment of the workpiece.

Therefore, the conventional atmospheric plasma generator does not properly utilize the gas activated in a high energy state while passing through the discharge gap 31, and thus an amount of energy loss is increased, and only a part of the activated gas is used to be treated. Since it forms a glow plasma processing the, there is a problem that can not form a large plasma glow plasma.

In addition, the atmospheric pressure plasma generator has a power source electrode 20 and a ground electrode 10 installed on the left and right sides of the intermediate dielectric 30, and the object 40 is treated with the power source electrode 20 and the ground electrode ( 10 is processed while passing through the lower space portion, the to-be-processed object 40 to be conveyed must be transported while maintaining the grounded state between the power source 20 and the object 40 by the high frequency power source 25 The plasma is stably maintained to achieve the desired work.

Therefore, when the workpiece 40 is released from the ground state due to being lifted from the ground plate during the transfer, there is a problem that the processing operation is difficult to be made stably.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is that the energy which is activated in a high energy state while passing through the discharge gap is used to form a large-area glow plasma without leaking to the outside, resulting in energy efficiency. It is to provide an atmospheric pressure large-area glow plasma generating device that is high, and the processing speed of the water to be treated is improved.

According to the present invention, in the apparatus for generating a glow plasma at atmospheric pressure by supplying a high-frequency power source 25, it is composed of a pair of members, one side member is grounded and the other member is a ground electrode connected to the high frequency power source 25 10 and the power source electrode 20, the dielectric material 31 provided between the ground electrode 10 and the power source electrode 20, and the ground electrode 10 or the power source electrode so as to be spaced apart from the dielectric material 31 by a predetermined distance. A workpiece transfer path 19 which is concave in the center portion of the workpiece 20 to form a closed passage, and at least one side of the workpiece transfer path 19 is narrower than the workpiece transfer path 19. Provided is an atmospheric pressure large-area glow plasma generator, characterized in that it comprises a discharge gap 17 formed spaced apart from the dielectric 31 at intervals, and a gas flow path 11 formed to communicate with the discharge gap 17. do.

According to another feature of the present invention, the communication portion between the gas inlet path 11 and the discharge gap 17 has a recessed portion 15 formed spaced apart from the dielectric 31 at a wider interval than the discharge gap 17 It is formed, the depression 15 is provided with an atmospheric pressure large-area glow plasma generator, characterized in that the sealing bar (16) which is detachably inserted to partially seal the depression (15).

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

2 and 3 are exploded perspective and sectional views showing an embodiment of the present invention, respectively. Referring to this, the plasma generating apparatus has a workpiece transport path 19 sealed between the power supply electrode 20 and the ground electrode 10, and at least one side of the workpiece transport path 19 has a discharge gap ( 17) is formed, and the workpiece transfer path 19 between the power supply pole 20 and the ground electrode 10 in the entire amount of electricity without passing through the discharge gap 17, the gas activated in a high energy state to the outside By supplying to the large-area glow plasma to be processed, to be processed more stable and faster, as well as to increase the energy efficiency.

The ground electrode 10 is a metal block made of aluminum alloy, stainless steel, or the like, and a workpiece conveying path 19 which is concavely planarized so as to penetrate back and forth is formed in the center of the upper surface thereof. In addition, a pair of depressions 15 are formed on both sides of the workpiece transfer path 19 to communicate with the gas inflow path 11 therein, and the depression 15 and the workpiece transfer path ( Between the substrates 19, a discharge gap 17 plane-processed to be spaced apart from the dielectric 31 by a predetermined gap is formed. At this time, the recessed portion 15 and the discharge gap 17 are formed to extend only to the front and rear ends adjacent to the ground electrode 10, so that the supplied gas does not leak to the front and rear of the ground electrode 10, and the workpiece transfer path 19 To ensure that it is supplied only.

In addition, the discharge gap 17 is plane-processed 1 to 20 mm lower than the outer surface of the ground electrode 10 so as to be spaced apart from the dielectric material 31 at this interval, and the workpiece transfer path 19 is discharge gap. The plane is processed relatively lower than (17) so that the workpiece can be smoothly passed while being plane processed to an appropriate depth so that the plasma generated in the discharge gap 17 can be stably maintained. At this time, the reason why the discharge gap 17 is formed in a narrow gap of 1 to 20 mm is for smoothing the initial ignition of the plasma.

In addition, the discharge gap 17 is preferably formed in a width of 0.1mm to 50mm toward the workpiece transfer path 19, so that it is possible to maintain a stable glow plasma, when the initial gap of the plasma is less than 0.1mm If the thickness is 50 mm or more, the amount of power consumed in the discharge gap 17 increases, which makes it difficult to maintain the glow plasma in the workpiece transport path 19.

In addition, the gas inflow path 11 is formed so as to communicate with the depression 15 in both sides of the ground electrode 10, a plurality of orifices 13 are formed in the communication portion with the depression 15, the gas is Through the orifice 13 is configured to be evenly supplied to the entire section of the depression 15. At this time, only the argon or helium gas is supplied to the gas inflow path 11, or a gas containing a small amount of oxygen or nitrogen is supplied to these gases to maximize the amount of active radicals. In addition, a gas supply path not shown in the drawing connected to the gas inflow path 11 may be equipped with a heater for preheating and supplying the gas.

In addition, a rectangular frame frame 18 is fixedly installed on the upper surface of the circumferential part of the ground electrode 10 so that the power pole 20 can be inserted into the inside of the frame frame 18.

The power pole 20 is a metal block such as an aluminum alloy or stainless steel to which the high frequency power source 25 is connected. The power pole 20 is inserted into the edge frame 18, and a dielectric 31 is interposed therebetween so that the ground pole 10 is provided. It is installed in close contact with the upper surface is formed a closed workpiece transport path (19). In this case, an insulating material 12 is interposed between the edge frame 18 and the power pole 20. At this time, the high frequency power source 25 supplied to the power supply pole 20 is a power source 25 having a frequency of 2 MHz to 60 MHz is used, preferably a high frequency power source 25 of 13.56 MHz band.

The dielectric 31 is installed between the ground electrode 10 and the power source electrode 20 so that an arc does not occur when the power source 25 is applied, and a glow plasma is formed. Usually, alumina, quartz, or the like is used. Magnesium oxide thin film is coated with 1 ~ 20mm to increase gas.

The sealing bar 16 is removably inserted into the depression 15 of the ground electrode 10 to partially seal the depression 15 so as to adjust the supply amount and the supply position of the gas to be supplied. This is to keep the density of this gas constant even when the object to be processed is supplied while being supplied.

Referring to the working example of the present invention by the above configuration is as follows.

In the plasma generating apparatus, a workpiece transport path 19 enclosed between the power supply electrode 20 and the ground electrode 10 is formed, and discharge gaps 17 are formed at both sides of the workpiece transport path 19. By passing through the discharge gap 17, the gas activated in a high energy state is supplied to the workpiece transfer path 19 between the power supply electrode 20 and the ground electrode 10 without leaking to the outside. The large-area glow plasma can be maintained more stably, thereby increasing the processing speed of the object and improving energy efficiency.

At this time, even if the glow plasma of the workpiece transfer path 19 is turned off due to instability of the matching state with the external gas or the like, the glow plasma is automatically turned on again by the plasma generated from the discharge gap 17, thereby ensuring stable glow. It forms a plasma.

In addition, since the plasma generating apparatus is processed while the workpiece is passed between the power pole 20 and the ground electrode 10, the plasma generation device is disposed between the power pole 20 and the ground electrode 10 without separately grounding the workpiece of various materials. It is automatically exposed to the glow plasma generated from the surface treatment, cleaning, sterilization, etc. is made to be stable and uniform.

According to the present invention as described above, the closed workpiece transfer path between the power source electrode 20 and the ground electrode 10 without the gas is activated in a high energy state while passing through the discharge gap 17 to the outside. By supplying to (19) to maintain the large-area glow plasma more stably, it is possible to increase the processing speed of the object to be processed, as well as to improve the energy efficiency.

In addition, since the object to be processed is directly processed between the power source electrode 20 and the ground electrode 10, there is an advantage that a stable and uniform processing operation is made by being automatically exposed to the glow plasma even if not separately grounded.

Claims (2)

In the apparatus for generating a glow plasma at atmospheric pressure by supplying a high-frequency power source 25, the ground electrode 10 and the power source is composed of a pair of members, one member is grounded and the other member is connected to the high-frequency power source 25 A dielectric part 31 provided between the pole 20, the ground electrode 10, and the power supply electrode 20, and a central portion of the ground electrode 10 or the power supply electrode 20 so as to be spaced apart from the dielectric material 31 by a predetermined distance. A workpiece conveyance path 19 which is formed concave to form an airtight passage, and at least one side of the workpiece conveyance path 19 at an interval smaller than that of the workpiece conveyance path 19 compared to the workpiece conveyance path 19; 31) and a gas discharge path (11) formed so as to communicate with the discharge gap (17) formed spaced apart from the atmospheric pressure large-area glow plasma generator. The method of claim 1, wherein the communication portion between the gas inlet path 11 and the discharge gap 17 is formed with a recess 15 formed spaced apart from the dielectric 31 at a wider interval than the discharge gap 17, And a depression bar (16) which is detachably inserted into the depression (15) and partially seals the depression (15).

Images