KR101002335B1 - System for Atmospheric Pressure Plasma - Google Patents

Abstract

The present invention relates to an atmospheric pressure plasma processing apparatus capable of forming stable and abundant radicals through an inverted triangle or triangular electrode arrangement, wherein the first and second electrodes are spaced apart by a predetermined interval in the vertical direction, and The first and second electrodes are spaced apart by a predetermined interval in the vertical direction, and between the first and second electrode pairs and the second electrode pair arranged in parallel with the first electrode pair on one side of the first electrode pair. A third electrode pair in which the first and second electrodes are spaced apart at predetermined intervals in a left and right direction, an RF power source for applying RF to the first electrodes of the first, second and third electrode pairs, and the first A ground terminal for grounding the second electrode of the first, second, and third electrode pairs and the first, second, and third electrode pairs are disposed, and plasma is applied to a space between the electrodes of the electrode pairs according to the RF power application. With the chamber being generated It characterized by eojim.

Atmospheric Pressure Plasma, Cleaning, Ashing, Etching, Radical

Description

Atmospheric Pressure Plasma

1 is a schematic diagram of a conventional direct type atmospheric pressure plasma processing apparatus;

2 is a schematic diagram of a conventional remote atmospheric plasma processing apparatus;

3 is a schematic view showing the principle of an atmospheric pressure plasma processing apparatus according to a first embodiment of the present invention;

4 is a detailed view of the atmospheric pressure plasma processing apparatus of FIG.

5A to 5C are waveform diagrams of RF used in the atmospheric pressure plasma processing apparatus of the present invention.

6 is a schematic view showing the principle of an atmospheric pressure plasma processing apparatus according to a second embodiment of the present invention;

Description of the Related Art [0002]

31 to 36: electrode 40: chamber

41 cooling device 42 transfer device

43: pumping system 44: RF power source

45 gas mixing unit 46 MFC unit

47: filter portion 48: valve portion

50 substrate 61a, 61b gas inlet                 

62: plasma gas outlet 301: first electrode pair

302: second electrode pair 303: third electrode pair

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to equipment used in the manufacture of liquid crystal displays or semiconductor devices, and more particularly, to an atmospheric pressure plasma processing apparatus capable of forming stable and abundant radicals through an electrode arrangement having an inverted triangle or triangle structure.

Plasma refers to an ionized gas state composed of ions, electrons, radicals, etc., which is caused by very high temperatures, strong electric fields, or high frequency electromagnetic fields. Is generated.

Particularly, plasma generation by glow discharge is performed by free electrons excited by direct current (DC) or high frequency electromagnetic fields. The excited free electrons collide with gas molecules to activate active groups such as ions, radicals, and electrons. (active species) are produced. And such active groups physically or chemically act on the surface of the material to change the surface properties. In this way, intentionally changing the surface properties of the material by the active group (plasma) is called 'surface treatment'.

On the other hand, in general, the plasma treatment method refers to a method of depositing a reaction material into a plasma state and depositing it on a substrate or using the plasma reaction material to clean, ash or etch the reaction material. .                         

Such a plasma processing method can classify under which atmospheric pressure the region where the plasma state is formed is in the chamber.

Conventionally, a method of generating a thin film on a substrate by generating a glow discharge plasma under a low pressure close to a vacuum, or etching or ashing a predetermined material formed on the substrate has been used. However, such a low pressure plasma processing method requires expensive equipment such as a vacuum chamber, a vacuum exhaust device, and the like, and also has a problem in that equipment maintenance and vacuum pumping time are lengthened because of a complicated structure in the apparatus. Therefore, in the case of a liquid crystal display device in which a plasma treatment is required for a large-area substrate, it is difficult to use it due to a cost burden that increases according to the size of the substrate.

For this reason, a method of generating a discharge plasma under a pressure near atmospheric pressure (atmospheric pressure) in which vacuum equipment is not required has been proposed. As such, a device for generating plasma under atmospheric pressure is referred to as a system for atmospheric pressure plasma.

However, in the atmospheric pressure state, the plasma discharge process is switched from the glow discharge generated during the discharge between the two electrodes in the chamber to the arc discharge in the thermodynamic equilibrium state, and thus does not exhibit stable plasma characteristics. It was not suitable to proceed.

In this case, if one of the two electrodes in the plasma processing chamber is insulated with a dielectric material having good insulating properties, and then RF (Radio Frequency) is applied to the other side, a silent discharge between the two electrodes even at atmospheric pressure. When this occurs, using an inert gas, for example, He and Ar, in a metastable state as a carrier gas, a plasma in a uniform and stable state can be obtained even at atmospheric pressure.

Hereinafter, with reference to the accompanying drawings will be described a conventional atmospheric pressure plasma processing apparatus (Atmospheric Pressure Plasma System) as follows.

The conventional atmospheric pressure plasma processing apparatus can be classified into a direct type and a remote type according to the arrangement positions of the first plate to which RF is applied and the second plate that is grounded.

1 is a schematic diagram of a conventional direct type atmospheric pressure plasma processing apparatus.

As shown in FIG. 1, a conventional direct atmospheric plasma processing apparatus includes a chamber 17 having a gas inlet opening 18 and gas outlet openings 19a and 19b, and a stage provided on a lower surface of the chamber 17. 10 and first and second plates 11 and 12 formed to face the surface of the stage 10 and spaced apart from the stage 10 so as to face each other, and are provided outside the chamber 17 to An RF power source 13 for generating and applying a high frequency RF to the first plate 11 and a gas supply unit 15 for supplying a reactive gas or an atmosphere gas through the gas inlet opening 18 of the chamber 17. And a filter 16 for filtering the reaction gas or the atmosphere gas supplied from the gas supply unit 15 to the chamber 17. Here, the second plate 12 is grounded, and the surfaces of the first and second plates 11 and 12 are protected by an insulator.                         

Thus, the operation of the conventional direct type atmospheric pressure plasma processing apparatus configured as follows will be described.

That is, when the substrate 20 is placed on the second plate 12, the gas is supplied from the gas supply unit 15 to the chamber 17 and RF is applied to the first plate 11. The supply gas between the first and second plates 11 and 12 is in a plasma state.

At this time, any material is deposited on the substrate 20 according to the components of the reactive gas or the atmosphere gas supplied from the gas supply unit 15 and the RF power applied to the first and second plates 11 and 12. The material deposited or formed on the substrate 20 is ashed or etched, cleaned and surface treated (hydrophilic / hydrophobic formation of the surface).

Here, the gas outlet openings 19a and 19b are outlets of gases remaining after the plasma surface treatment on the substrate 20.

The conventional direct atmospheric plasma processing apparatus also has a strong cleaning power by using a bombardment of ions accelerated by the electric field (E field) when the RF power is applied, and has a strong cleaning power, cleaning the organic material, alignment film and PR (Photo Resist) Ash and pattern etching are possible. In this case, cleaning and maintenance can be carried out up to 7 days or more.

In addition, since strong RF power is applied, by-products are exhausted through the outlet opening of the chamber in the same manner as in the vacuum method, particles are generated in the substrate 20 or the substrate 20 is contaminated. There is no phenomenon.

In addition, in the area between the first and second plates 11 and 12, the up, down, left and right can be cleaned simultaneously.

However, in the conventional direct pressure plasma processing apparatus, since an electric field (E-Field) acts strongly between the first and second plates 11 and 12 when RF power is applied, damage is caused in the metal wiring of the substrate 20. ) Is more likely to occur. In some cases, there may be the same ion damage as the vacuum plasma process.

2 is a schematic diagram of a conventional remote atmospheric plasma processing apparatus.

As shown in FIG. 2, the conventional remote atmospheric pressure plasma processing apparatus includes a chamber 21 having a gas inlet opening 29 and first and second plates formed to face each other in the left and right directions in the chamber 21. 23, 24, an RF power source 26 generating RF and applying RF to the first plate 23, and a gas or an atmosphere gas through the gas inlet opening 29 of the chamber 21. The gas supply part 27 which supplies and the filter 28 which filters the reaction gas or atmospheric gas supplied from the said gas supply part 27 to the chamber 21 are comprised.

Here, the second plate 24 is grounded.

Thus, the operation of the conventional remote atmospheric pressure plasma processing apparatus constructed as follows is as follows.

In the conventional remote atmospheric plasma processing apparatus, when RF is applied to the second plate 23, a glow plasma is generated between the first and second plates 23 and 24. In this case, the first and second Surface treatment due to the glow plasma occurs on the substrate 20 formed below the chamber 21 in a direction perpendicular to the plates 23 and 24.                         

The substrate 20 is conveyed by the conveying device 22, and the drawing shows that the process proceeds in-line.

In the conventional remote atmospheric plasma processing apparatus, unlike the conventional direct atmospheric plasma processing apparatus described above, the first and second plates 23 and 24 are positioned in a direction perpendicular to the substrate, and at this time, the substrate 20 ) Is characterized in that the surface treatment is performed on the substrate outside the chamber 21 located outside the chamber 21 and moving in-line. Therefore, since the surface treatment is performed on the substrate 20 outside the chamber 21, the gas exiting the glow plasma state through the predetermined outlet reacts with the substrate 20 without requiring a separate exhaust system. In addition, substances other than the reaction are released to the outside.

The conventional remote type (shower type) atmospheric pressure treatment apparatus is less damage because the surface treatment is performed on the substrate 20, the influence of the electric field is minimized, and depends on the chemical reaction of pure radicals and ions. Therefore, the damage of the metal wiring formed on the substrate 20 is minimized.

However, the conventional remote atmospheric pressure treatment apparatus has a weak cleaning power due to the minimization of the influence of the electric field, and causes a problem in that the amount of the reactive gas or the atmospheric gas is increased.

The conventional atmospheric pressure plasma processing apparatus as described above has the following problems.

In the case of the direct pressure plasma processing apparatus of the direct type, since the electric field directly acts on the substrate, there is a high possibility of damage to the metal wiring formed on the substrate, and there may be damage caused by ions generated to the same degree as the vacuum plasma process depending on the application process. have.

In the case of a remote atmospheric plasma processing apparatus, there is a disadvantage that the cleaning power is weaker than that of the electrode system, and a large amount of gas inflow is required, resulting in a cost problem such as exhaust treatment.

Thus, there is a problem in both the direct method and the remote method.

An object of the present invention is to provide an atmospheric pressure plasma processing apparatus capable of forming stable and abundant radicals through an electrode arrangement having an inverted triangle or triangle structure.

In the atmospheric pressure plasma processing apparatus of the present invention for achieving the above object, the first electrode pair and the first electrode and the second electrode are spaced apart by a predetermined interval in the vertical direction, and the first and second electrodes are spaced by the predetermined interval in the vertical direction The first and second electrodes are spaced apart from each other in the left and right direction between the second electrode pair arranged parallel to the first electrode pair on one side of the first electrode pair, and between the first and second electrode pairs. And a third electrode pair arranged to be arranged, an RF power source for applying RF to the first electrodes of the first, second and third electrode pairs, and the second electrodes of the first, second and third electrode pairs. A ground terminal for grounding and the first, second and third electrode pairs are disposed, and the chamber is provided with a chamber in which plasma is generated in the space between the electrodes of the electrode pairs as the RF power is applied.

The third electrode pair is positioned below the first and second electrode pairs.                     

The third electrode pair is positioned above the first and second electrode pairs.

The chamber is provided between the first and second electrode pairs, and has a plasma gas outlet at a lower end corresponding to a region between the first and second electrodes of the third electrode pair.

The substrate to be plasma-processed is positioned under the plasma gas outlet of the chamber.

The substrate is loaded / unloaded in a robotic or track manner.

The spacing between the substrate and the chamber is within 5 mm.

Each electrode of the first, second and third electrode pairs is plate-shaped or bar-shaped.

The apparatus further includes a cooling device for cooling all the first and second electrodes of the first, second and third electrode pairs.

The chamber has a gas inlet for receiving a reaction gas or an atmosphere gas from the outside of the chamber.

When the reactive gas or the atmosphere gas is a noxious gas, a chamber processing unit for the noxious gas is further provided.

The waveform of the RF power source is any one of a square wave type, a sine wave type, and a pulse waveform.

When the waveform of the RF power source is a pulse waveform, the RF is 10 to 50 KHz.

When the waveform generated by the RF power source is a square or steady wave, the RF is 13.56 MHz.                     

The power of the RF power source is 1000 to 5000W.

Hereinafter, an atmospheric pressure plasma processing apparatus of the present invention will be described in detail with reference to the accompanying drawings.

3 is a schematic view showing the principle of an atmospheric pressure plasma processing apparatus according to a first embodiment of the present invention.

As shown in FIG. 3, the atmospheric pressure plasma processing apparatus according to the first exemplary embodiment of the present invention arranges the first and second electrode pairs 301 and 302 in the horizontal direction at predetermined intervals on the left and right sides, respectively. A third electrode pair 303 is formed in a lower space between the two electrode pairs in a direction perpendicular to the directions of the electrodes of the first and second electrode pairs 301 and 302. RF power is applied to one electrode (31, 33, 36) of each electrode pair (301, 302, 303) and grounds the other one electrode (32, 34, 35). After generating gas in the plasma state (radical, high energy state ions) in the space between the two electrodes of 303, the gas in the plasma state is finally passed through the lower portion of the third electrode pair 303. .

A substrate (not shown) corresponds to the lower portion of the third electrode pair 303 so that the surface treatment of the substrate is activated by the rich plasma gas generated in the three pairs of electrodes 301, 302, and 303. . In this case, since the gas of about 3 times as much plasma is supplied as compared with the conventional atmospheric pressure plasma processing apparatus which consists of a pair of plate electrode, the plasma processing process which stabilizes is stabilized and the plasma process to process, for example, Depending on the process of deposition, ashing, cleaning, etching, etc., the speed of progress is increased.

Hereinafter, an atmospheric pressure plasma processing apparatus according to a first embodiment of the present invention will be described in detail with reference to the drawings including a chamber.

4 is a view showing the atmospheric pressure plasma processing apparatus of FIG. 3 in detail.

As shown in FIG. 4, the atmospheric pressure plasma processing apparatus according to the first exemplary embodiment of the present invention has a chamber 40 including predetermined gas inlets 61a and 61b, a plasma gas outlet 62, and spaced apart from the left and right by a predetermined interval. And the first and second electrode pairs 301 and 302 formed of upper and lower electrodes 31, 32 or 33 and 34 parallel to each other, and the phase between the first and second electrode pairs 301 and 302, A third electrode pair 303 including left and right electrodes 35 and 36 formed in a direction perpendicular to the lower electrodes 31, 32, or 33 and 34, and the first, second and third electrode pairs 301 and 302. RF power source 44 for applying RF (Radio Frequency) to one electrode (31, 33, 36) of the 303, and gas supply unit (45, 46) for supplying a reactive gas or an atmosphere gas to the chamber (40) , 47, 48 and a cooling device 41 connected to all the electrodes of the first, second, and third electrode pairs 301, 302, and 303.

Here, the other electrodes 32, 34, and 35 of the first, second, and third electrode pairs 301, 302, and 303 are grounded, and the substrate 50 on which the plasma surface treatment is performed is connected to the plasma gas outlet. Located at the lower portion of 62), a rich plasma gas such as radicals supplied from the chamber 40 is supplied. The substrate 50 is transferred by the transfer device 42, and the plasma surface treatment is performed on the in-line.

At this time, the separation degree between the substrate 50 and the chamber 40 is about 5mm.                     

The substrate 50 may be transferred on the in-line in both a robot method and a track method.

The gas supply units 45, 46, 47, and 48 supply gases such as He, SF ₆ , Ar, and O ₂ from respective MFCs 46a, 46b, 46c, and 46d of the mass flow control (MFC) unit 46. The flow rate is controlled through the filter unit 47 and the valve unit 48 for each gas and supplied to the chamber 40 through the gas mixing unit 45.

In this case, any one or more of the above-described gases may be selected and supplied through the filter unit 47 and the valve unit 48, and the above-described gas, for example, CF ₄ or N ₂ , may be used. Gas may be further formed by supplying a separate MFC to a portion where the MFC is not formed below the filter unit 47.

When using a fluorinated (F) gas-based toxic gas (Toxic gas), the box (boxing) system according to the supply of the noxious gas should be provided.

The electrodes 31 to 36 of the first, second, and third electrode pairs 301, 302, and 303 may be formed in a plate shape or a bar shape.

Although not shown, the other of the first, second, and third electrode pairs 301, 302, and 303 grounded to maintain a stable plasma state that does not transition to an arc in the chamber. 32, 34, 35 may be formed of a dielectric.

Since the electrodes 31 to 36 may be overheated according to the strength of the RF 44, each of the electrodes 31 to 36 is connected to the cooling device 41 outside the chamber 40.

The pumping system 43 formed at one side of the lower portion of the chamber 40 serves to absorb and decompress a gas that has not reacted with the substrate 50 among the plasma gases from the plasma gas outlet 62 of the chamber 40.

5A to 5C are waveform diagrams of RF used in the atmospheric pressure plasma processing apparatus of the present invention.

RF (Radio Frequency) applied to the one electrode (31, 33, 36) of the first, second, third electrode pair (301, 302, 303) is a square wave type, as shown in Figure 5a, As shown in FIG. 5B, a sine wave type or as shown in FIG. 5C, a pulse waveform may be used.

In the case of the pulse waveform, as shown in Figure 5c is applied at a frequency of 10KHz to 50KHz, in the case of a square wave (sine wave) type, as shown in Figures 5a and 5b (sine wave) is applied at a frequency of 13.56MHz.

As described above, one side electrodes 31, 33, and 36 of the first, second, and third electrode pairs 301, 302, and 303 apply an RF power of 1000 to 5000 W to receive the RF waveform. Is coupled to the RF power source 44.

In the atmospheric pressure plasma processing apparatus according to the first embodiment of the present invention, structures of the first, second, and third electrode pairs 301, 302, and 303 are arranged in an inverted triangle to provide a rich and stable plasma gas to the substrate 50. Can be supplied to

6 is a schematic view showing the principle of an atmospheric pressure plasma processing apparatus according to a second embodiment of the present invention.

6, the atmospheric pressure plasma processing apparatus according to the second embodiment of the present invention has the same structure except that the electrode arrangement is replaced from the inverted triangle to the triangle in the structure of the first embodiment. The second and third electrode pairs 304, 305, 306 can be arranged in a triangle to supply abundant and stable radicals.

That is, in the atmospheric pressure plasma processing apparatus according to the second embodiment of the present invention, the first and second electrode pairs 304 and 305 in the horizontal direction are disposed at predetermined intervals on the left and right sides, respectively, and the first and second electrode pairs are arranged. The third electrode pair 303 is formed in the upper space between the first and second electrode pairs 304 and 305 in a direction perpendicular to the directions of the electrodes 71, 72, 73, and 74. In addition, RF power is applied to one electrode 71, 73, 76 of each electrode pair 304, 305, 306, and the other electrode pair 304, 305, After generating gas in the plasma state (radical, high energy state ions) in the space between the two electrodes of 306, it is finally lower than the third electrode pair 306, and the first and second electrode pairs. The gas in the plasma state is allowed to pass through the space between 304 and 305.

The pair of electrode pairs 304, 305, and 306 are lower portions of the third electrode pair 306 and correspond to a substrate (not shown) at the lower end of the space between the first and second electrode pairs 304 and 305. The abundant plasma gas generated in) causes the surface treatment of the substrate to be activated. In this case, as in the first embodiment, since the gas of about 3 times as much plasma is supplied as compared with the conventional atmospheric pressure plasma processing apparatus consisting of a pair of plate electrodes, the plasma processing process to be stabilized is to be processed. In this case, the progression speed is increased according to a plasma process, for example, deposition, ashing, cleaning, and etching.

The atmospheric pressure plasma processing apparatus of the present invention is applicable to all processes requiring plasma processing, ranging from deposition, cleaning, ashing, etching, and surface treatment. Moreover, it can use not only the liquid crystal display device which requires a plasma processing for a large area board | substrate, but also a semiconductor manufacturing process.

The atmospheric pressure plasma processing apparatus of the present invention as described above has the following effects.

Basically, the atmospheric pressure plasma processing apparatus does not require a vacuum system, thereby improving space efficiency. Thus, by arranging the first, second, and third electrode pairs in the inverted triangle or triangle in the atmospheric plasma processing chamber, plasma gas such as abundant radicals is generated. Can be supplied to a substrate, whereby the effect of stabilizing the process and improving the reaction rate can be further obtained.

Claims (15)

A first electrode pair in which the first and second electrodes are spaced apart by a predetermined interval in the vertical direction; A second electrode pair in which first and second electrodes are spaced apart at predetermined intervals in a vertical direction and arranged in parallel with the first electrode pair on one side of the first electrode pair; A third electrode pair between the first and second electrode pairs, the first and second electrodes being arranged spaced apart from each other in a horizontal direction; An RF power source for applying RF to the first electrodes of the first, second, and third electrode pairs; A ground terminal for grounding a second electrode of the first, second, and third electrode pairs; And The first, second and third electrode pairs are arranged, the atmospheric pressure plasma processing apparatus characterized in that it comprises a chamber for generating a plasma in the space between the electrodes of the electrode pairs in accordance with the RF power applied. The method of claim 1, And the third electrode pair is positioned below the first and second electrode pairs. The method of claim 1, And the third electrode pair is positioned above the first and second electrode pairs. The method of claim 1, And the chamber is disposed between the first and second electrode pairs and has a plasma gas outlet at a lower end corresponding to a region between the first and second electrodes of the third electrode pair. The method of claim 4, wherein Atmospheric pressure plasma processing apparatus characterized in that the substrate which is supported by the transfer device, the plasma processing is located below the plasma gas outlet of the chamber. The method of claim 5, And the substrate is loaded / unloaded in a robotic or track manner. The method of claim 5, Atmospheric pressure plasma processing apparatus characterized in that the interval between the substrate and the chamber within 5mm. The method of claim 1, Atmospheric pressure plasma processing apparatus, characterized in that each electrode of the first, second, and third electrode pair is a plate type or a bar type. The method of claim 1, And a cooling device for cooling all the first and second electrodes of the first, second and third electrode pairs. The method of claim 1, The chamber has an atmospheric pressure plasma processing apparatus comprising a gas inlet for receiving a reaction gas or an atmosphere gas from the outside of the chamber. delete The method of claim 1, And the waveform of the RF power source is any one of a square wave type, a sine wave type, and a pulse waveform. The method of claim 12, When the waveform of the RF power source is a pulse waveform, RF is 10 to 50 KHz, the atmospheric pressure plasma processing apparatus. The method of claim 13, When the waveform generated from the RF power source is a square or steady wave, RF is 13.56MHz, characterized in that the atmospheric pressure plasma processing apparatus. The method of claim 1, Atmospheric pressure plasma processing apparatus characterized in that the power of the RF power source is 1000 to 5000W.

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