KR20020044836A - Accuracy cleaning and surface modification method and thereof apparatus by using discharge plasama in atmosphere - Google Patents

Abstract

PURPOSE: A method and an apparatus for fine cleaning and surface modification using atmosphere plasma are provided to clean and modify a surface by using plasma discharge. CONSTITUTION: A base plate(12) is supported by a multitude of support portion(10). A couple of guide roll(14) is installed at both ends of the base plate(12). A conveyer belt(16) is wound around the guide rolls(14). A support beam(20) is buried between lower support portions(10) of the base plate(12). A drive motor(22) is fixed to a center portion of the support beam(20). A drive roll(24) is fixed to a drive motor(22). An inverter(26) is installed to the drive motor(22). An anode electrodes(40) is fixed to a center portion of an upper surface of the base plate(12). A barrier rib(32) is formed at an upper portion of the anode electrode(40). A power supply(60) is fixed to an upper portion of the barrier rib(32). A reaction room(30) is formed by the barrier rib(32). A cathode electrode(50) is formed at an upper portion of the reaction room(30). The power supply(60) is connected with the anode electrode(40) and the cathode ray tube(50).

Description

Precise cleaning and surface modification using atmospheric pressure plasma and its apparatus {ACCURACY CLEANING AND SURFACE MODIFICATION METHOD AND THEREOF APPARATUS BY USING DISCHARGE PLASAMA IN ATMOSPHERE}

The present invention can be widely used in fields requiring precise surface modification, such as semiconductors, electronic devices for flat panel displays, large-capacity PCBs, high-quality fibers, mechanical parts, and various products requiring continuous production using plasma generated at atmospheric pressure. The present invention relates to a precision cleaning and surface modification method using an atmospheric pressure plasma and a device thereof.

Conventionally, in order to precisely clean the surface of semiconductors, electronic devices for flat panel displays, large-capacity PCBs, or mechanical parts that require surface modification (SURFACE MODIFICATION), large-scale facilities are required or various pollutants by wet By discharging, the cost of production is rapidly increased and the cost of development of the product is delayed and the development period is delayed due to the failure to actively cope with the change of the characteristics of raw materials according to the production of high quality products.

For example, when manufacturing a flat panel display, an ultraviolet excimer laser (UV EXIMER LASER) is used or chemicals and ultrapure water are used to remove organic films or other contaminants on the glass surface.

However, when cleaning with an ultraviolet excimer laser, the discharge lamp oscillates the band wavelength of 185 nm or 254 nm and emits ultraviolet rays between the gaps while maintaining a gap of approximately 2 to 4 mm with the flat panel display to be cleaned. It is necessary to convert the oxygen into ozone and remove the organics and other foreign substances on the glass surface by using the generated ozone, which is very complicated and expensive to clean, and the life of the UV excimer laser light emitting lamp is short. It causes the disadvantage of excessive waste of manpower and time.

In addition, even when cleaning with chemicals or ultrapure water, a device that generates a large amount of midstream water and a surface must be modified or a large amount of used water must be reprocessed after cleaning, thus requiring complicated auxiliary facilities and manpower to maintain it. This is necessary separately, causing the disadvantage of raising the manufacturing cost of LCD or PDP.

In addition, in order to clean the semiconductor line, high-quality fiber, PCB, etc., a vacuum must be formed and the cleaning work must be performed in a vacuum. Therefore, the work cannot be maintained. This rises significantly and draws the disadvantage of no profit.

In order to overcome this drawback, many techniques for precise cleaning in vacuum have been proposed and published, but they are limited to the degree of utilizing the equipment necessary for cleaning in the form of batch. The disadvantage of not increasing is present.

The present invention has been created to solve the problems of the surface modification method of the prior art as described above, the precision of semiconductor, flat panel display panel, large-capacity PCB, high-quality fiber, organic chemical products and various products requiring continuous production In areas where cleaning and surface modification are required, precision cleaning and surface modification using atmospheric pressure plasma enables the surface coating or contaminants present on the surface to be continuously cleaned and modified through the plasma discharge generated under atmospheric pressure. It is an object of the present invention to provide a method and an apparatus thereof.

The above object of the present invention comprises the steps of: waiting for the surface to be subjected to continuous processing on the conveyor belt for precision cleaning or modification treatment; After the step, the height adjusting member is adjusted according to the characteristics of the object to be treated to control the discharge gap between the positive electrode and the negative electrode, while introducing a reaction gas into the reaction chamber for stabilizing the plasma under atmospheric pressure and applying a voltage to the plasma under atmospheric pressure. Generating; After the step of transferring the conveyor belt while adjusting the speed at a speed of 0.01 ~ 60m per minute to put the workpiece to the reaction chamber; It is achieved by including a step of continuously cleaning or surface-modified by the generated plasma is subjected to the target material introduced into the reaction chamber through the above steps.

In addition, the present invention and the base plate is fixed by a plurality of supports; A pair of guide rolls fixed to both ends of the base plate; A drive roll installed on a support beam fixed across the support under the base plate and rotatable by a drive motor; A pair of conveyor belts wound around the driving rolls and the guide rolls and disposed at both ends of the base plate along a longitudinal direction of the base plate; A positive electrode fixed to the central portion in the longitudinal direction of the base plate; A reaction chamber covering the positive electrode and positioned above the conveyor belt and partitioned by a partition wall; A negative electrode installed on the upper surface of the reaction chamber so as to be adjustable in height; It is achieved by including a power supply connected to the positive electrode and the negative electrode.

1 is a front view schematically showing the configuration of a device according to the invention,

2 is a plan view of FIG.

Explanation of symbols on the main parts of the drawings

10: support, 12: base plate,

14: guide roll, 16: conveyor belt,

22: drive motor, 24: drive roll,

26: inverter, 30: reaction chamber,

40: positive electrode, 50: negative electrode,

54: height adjustment member, 60: power supply.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an accompanying drawing.

1 is a front view showing a schematic configuration of an apparatus according to the present invention, and FIG. 2 is a plan view of FIG.

1 to 2, a base plate 12 supported by a plurality of supports 10 is provided, and a pair of guide rolls 14 are installed at both ends of the base plate 12.

The conveyor belt 16 is wound around the guide roll 14, and the conveyor belt 16 is rotatably installed at a predetermined distance from the upper surface of the base plate 12.

The conveyor belt 16 is installed so as not to proceed while covering the entire upper surface of the base plate 12 and to have a small width only at both ends in the longitudinal direction, that is, the transverse direction of the base plate 12.

In other words, the pair of conveyor belts 16 are rotated and the center portion of the base plate 12 is vacant with a slight width adjacent to both ends along the longitudinal direction of the base plate 12.

The support beam 20 is disposed between the lower supporters 10 of the base plate 12, and the driving motor 22 is fixed to the central portion of the support beam 20.

A drive roll 24 is fixed to the drive motor 22, and a part of the conveyor belt 16 is wound around the drive roll 24 to be rotatably installed.

An inverter 26 is installed in the drive motor 22, and the inverter 26 enables to control the speed of the drive motor 22 as well as the forward and reverse rotation.

The positive electrode 40 is fixed to the center of the upper surface of the base plate 12, the positive electrode 40 is preferably a plate-shaped electrode.

Directly above the positive electrode 40, the partition wall 32 is provided with a slight distance from the conveyor belt 16.

The partition wall 32 has a rectangular box shape, which is supported on both sides by an unillustrated bracket extending from both sides of the long side of the base plate 12 and is extended upward, and keeps all surfaces except the lower side in a reaction chamber ( 30) is preferred.

The power supply 60 is fixed to the top surface of the partition 32, and a plurality of gas inlets 34 are formed at each side.

The reaction gas in the reaction chamber 30 supplied through the gas inlet 34 is preferably made of any one selected from inert gas, oxidizing gas, and reducing gas, or a mixture thereof.

The power supply 60 is preferably a DC power supply or a PULSED DC POWER SUPPLY (high voltage micropulse power supply), and a power supply capable of varying voltage and frequency within a range of 1 to 50 kv and 1 to 20 kHz is preferable.

The height adjusting member 54 is fixed to the ceiling of the reaction chamber 30, and the height adjusting member 54 uses a rack and pinion known in the art, or a guider that can move up and down along the guide member. Can be made.

A negative electrode 50 in the form of a discharge tube is fixed to the lower end of the height adjusting member 54, and a nozzle 52 for adjusting the discharge gap is added.

Each electrode 40, 50 is connected to a power supply 60, respectively.

In addition, in FIG. 2, the power supply 60 is drawn out to one side for convenience of illustration, and the guide rolls 14 are made of two sets of roll shafts 14a to drive a pair of conveyor belts 16. It is stated that it is connected.

The conveyance speed of the conveyor belt 16 for precise cleaning and modification of the surface of the workpiece 90 can be varied depending on the surface modification characteristics of the workpiece 90, but it can be adjusted at a speed of approximately 0.01 to 60 m per minute. This is preferable.

The present invention made up of such a configuration works as follows.

First, a step of preparing in an atmospheric state for precisely cleaning or modifying the surface of the workpiece 90 is performed.

The object 90 may be a product in the form of LCD, PDP glass and panel, and may also be a fiber, a polymer resin, a polymer, or the like.

After the step is completed according to the characteristics of the workpiece 90, the positive electrode 40 and the negative electrode (by adjusting the height adjusting member 54 while applying a voltage to each electrode 40, 50 through the power supply 60) The discharge gap between 50) is adjusted.

At the same time, the step of generating a plasma by introducing a reaction gas made of any one or a mixture of inert gas, oxidizing gas, and reducing gas through the gas inlet 34 into the reaction chamber 30.

The initial corona discharge is started by the initial voltage of 10 kV applied to the electrode, at which time between the electrodes is about 10 mm and the current flowing is 100 mA, which is low in discharge efficiency and discharge density.

The discharge distance is increased by applying the high frequency of 20kHz while applying the high voltage of 50kV higher than the initial applied voltage while increasing the discharge efficiency and increasing the current density. The current flowing at this time is 800 mA.

Under these conditions, the discharge density increases depending on the amount of gas when the flow rate of the mixed gas, such as inert gas such as argon or oxidizing gas such as oxygen, is adjusted in order to stabilize the discharge plasma and impart hydrophilicity to the workpiece. do.

In particular, in order to maintain the discharge in a large area, it is necessary to supply the reaction gas evenly on the front.

The reaction gas supplied to the reaction chamber 30 through the above steps stabilizes the plasma generated under atmospheric pressure.

Subsequently, the driving motor 22 is driven to transfer the conveyor belt 16 to the inverter 26 while controlling the transfer speed of the conveyor belt 16 at a speed of about 0.01 to 60 m per minute to feed the object 90 into the reaction chamber 30. Follow the steps.

The workpiece 90 introduced into the reaction chamber 30 is moved in accordance with the driving speed of the conveyor belt 16 to perform continuous fine cleaning or surface modification.

Thereafter, when the workpiece 90 is discharged from the reaction chamber, the surface cleaning or reforming operation of the workpiece 90 is terminated and transferred to a later process by a separate transfer member.

EXAMPLE

Table 1 below measures the cleaning effect after surface modification according to the surface modification method of the present invention, and measures the contact angle of the surface of the object 90 before and after cleaning (in this case, using a substrate glass for flat panel display). Will be compared.

Here, the contact angle refers to the angle at which the liquid is thermodynamically equilibrated on the solid surface, and the measurement of the contact angle is a known analytical technique mainly used in fields such as adhesion, surface treatment, and surface analysis of polymers. This allows for surface analysis that is sensitive to monolayer changes in ANGSTROM units.

This contact angle is a measure of the wettability of a solid surface, which is mostly measured by water droplets stuck to it, and the low contact angle indicates high wettability (hydrophilicity) and high surface energy, and the high contact angle indicates low wettability (hydrophobicity) and low surface energy. Indicates.

Comparative example of atmospheric plasma cleaning Contact Angle Uncoated glass Molybdenum glass Indium Kin Oxide Glass Nitrogen Indium Glass Before cleaning 42 16 58 60 After cleaning 12 5 18 8

As shown in Table 1, by generating a plasma at atmospheric pressure according to the present invention and by using the plasma to continuously process the surface modification of the workpiece, it is very easy to remove contaminants remaining on the surface of each workpiece. It can be clearly seen that to have excellent surface modification properties.

Such a surface modification method may be utilized to improve the quality of various electronic components, fibers, PCBs, plastics, painted parts, and molds.

In addition, it is easy to adjust the length of the discharge gap, for example, it can be utilized not only for large glass panels of 40 to 60 inches, but also for fine cleaning or surface modification of over-wide fibers, especially in the case of the discharge tube by the ultraviolet excimer laser at 400 mm or more. Uniform surface treatment is not possible over the area, but according to the present invention, it was found that a very uniform surface treatment is possible in the range of 900 to 1000 mm.

As described above in detail, the present invention can continuously surface-clean and surface-modify the workpiece by using a device capable of generating plasma under atmospheric pressure, thereby reducing manufacturing costs and shortening surface treatment time. This will provide productivity and quality improvement effects.

Claims (6)

Waiting the object to be processed 90 on the conveyor belt 16 for surface cleaning or reforming; After the step, by adjusting the height adjusting member 54 according to the characteristics of the object 90 to control the discharge gap between the positive electrode 40 and the negative electrode 50, and reacting the reaction gas for stabilizing the plasma at atmospheric pressure Introducing plasma into the chamber and applying a voltage to generate a plasma under atmospheric pressure; After the step, the conveyor belt 16 is transferred to the reaction chamber 30 by controlling the conveyance while controlling at a speed of 0.01 to 60 m per minute; Precise cleaning and surface modification using atmospheric pressure plasma, characterized in that it comprises a step of continuously cleaning or surface modification by the plasma generated to be processed (90) injected into the reaction chamber 30 through the above steps Way. The method of claim 1, wherein the discharge voltage applied between the positive electrode (40) and the negative electrode (50) is 1-50kv, and the frequency is 1-20kHz. The method of claim 1, wherein the reaction gas comprises at least one selected from an inert gas, an oxidizing gas, and a reducing gas, or a mixture thereof. 5. A base plate 12 fixed by a plurality of supports 10; A pair of guide rolls 14 fixed to both ends of the base plate 12; A drive roll (24) installed on a support beam (20) fixed across the support (10) below the base plate (12) and rotatable by a drive motor (22); A pair of conveyor belts 16 wound on the driving roll 24 and the guide roll 14 and rotatably disposed at both ends of the base plate 12 along the longitudinal direction; A positive electrode 40 fixed to a central portion in the longitudinal direction of the base plate 12; A reaction chamber 30 covering the positive electrode 40 and positioned above the conveyor belt 16 and partitioned by partition walls 32; A negative electrode 50 installed on the upper surface of the reaction chamber 30 so as to be adjustable in height; Precision cleaning and surface modification apparatus using an atmospheric pressure plasma, characterized in that it comprises a power supply (60) connected to the positive electrode 40 and the negative electrode (50). 5. The precision cleaning and surface modification apparatus using atmospheric pressure plasma according to claim 4, characterized in that the drive motor (22) is provided with an inverter (26) for controlling speed regulation and forward and reverse rotation. 5. The apparatus of claim 4, wherein the power supply (60) is a DC or high voltage micropulse power supply.