WO2018199373A1

WO2018199373A1 - Harmful gas processing facility using microwave plasma

Info

Publication number: WO2018199373A1
Application number: PCT/KR2017/004869
Authority: WO
Inventors: 강경두; 구민; 이성룡
Original assignee: 주식회사 클린팩터스
Priority date: 2017-04-26
Filing date: 2017-05-11
Publication date: 2018-11-01

Abstract

The present invention provides a harmful gas processing facility using microwave plasma, comprising: a microwave generation unit; a microwave transmission unit for transmitting and supplying microwaves generated in the microwave generation unit; and a plasma discharge unit which is provided in a pipe through which a harmful gas discharged from a process chamber flows, and which receives the microwaves from the microwave transmission unit so as to generate a plasma discharge therein, thereby decomposing harmful materials within the harmful gas, wherein the plasma discharge unit comprises: a plasma discharge chamber having a cylindrical plasma discharge space through which the harmful gas passes; an antenna unit which is provided in the plasma discharge chamber and arranged to encompass the outside of the plasma discharge space, and which has a plurality of slots for discharging, to the plasma discharge space, a microwave introduced therein; and a shielding member provided in the inner plasma discharge chamber of the antenna unit. Therefore, an antenna unit is formed to encompass a plasma discharge space and microwaves are supplied to the plasma discharge space through a plurality of slots, such that a uniform and efficient plasma discharge is formed inside the plasma discharge space, thereby enabling processing efficiency of harmful gas to be improved and costs to be reduced so as to be economical.

Description

Hazardous Gas Treatment Facility Using Microwave Plasma

The present invention relates to a noxious gas treatment facility using microwave plasma, and more particularly, by inducing a uniform plasma discharge in the plasma discharge space, it is possible to improve the removal rate of noxious substances in the noxious gas discharged from the process chamber and reduce costs. It relates to a harmful gas treatment facility using a microwave plasma that can be reduced.

In general, for the manufacture of semiconductors or displays, various raw materials are injected into a low pressure process chamber, and processes such as ashing, deposition, etching, photography, cleaning, and nitriding are performed. These processes produce or utilize hazardous gases that contain substances that correspond to various volatile organic compounds, acids, odor-causing gases, pyrophoric substances, greenhouse gases, or environmental regulatory substances such as PFCs.

In particular, gases called PFCs (perfluorocarbons) such as CF4, SF6, C2F6, and C3F8 are widely used in etching processes, thin film deposition, and reactor washing steps. It is very long and recognized as a major culprit of ozone depletion, and there are strong regulations for use in semiconductor processes.

Therefore, in order to remove contaminants in the harmful gas discharged in the above process, a vacuum pump is installed to make the process chambers in a vacuum state, and to generate plasma discharge using microwaves, and to process the harmful gas using the same. The technology to purify the harmful gas through the harmful gas treatment facility and release it to the atmosphere has been developed.

However, the conventional harmful gas treatment facility using the microwave plasma has a problem that the plasma is not uniformly and efficiently supplied to the plasma discharge space, the plasma discharge efficiency is lowered and the removal rate of the harmful substances is lowered.

The present invention is to provide a uniform and efficient microwave supply in the plasma discharge space to achieve a uniform plasma discharge to increase the removal rate of harmful substances in the harmful gas discharged from the process chamber, the microwave plasma can reduce the cost An object of the present invention is to provide a hazardous gas treatment facility.

The present invention is a harmful gas treatment facility using a microwave plasma for processing harmful gas discharged from the process chamber, the microwave generating unit for generating a microwave, the microwave for transmitting and supplying the microwave generated in the microwave generating unit Plasma discharge is installed in a pipe through which the harmful gas discharged from the transmission unit and the process chamber flows, and receives the microwaves from the microwave transmission unit to generate plasma discharge therein to decompose harmful substances in the harmful gas. Including a unit, The plasma discharge unit is installed between the first pipe through which the harmful gas discharged from the process chamber flows and the second pipe through which the harmful gas flows toward the vacuum pump, In communication with one pipe and the second pipe For example, a plasma discharge chamber having a cylindrical plasma discharge space through which the noxious gas passes, and an inner space installed in the plasma discharge chamber to surround the outside of the plasma discharge space, and into which the microwave is introduced, are formed. An antenna unit having a plurality of slots formed to be spaced apart from each other toward the plasma discharge space to release the microwaves introduced into the plasma discharge space, and installed in the plasma discharge chamber inside the antenna unit for the plasma discharge; It provides a harmful gas treatment facility using a microwave plasma including a shielding member for preventing the leakage of ions or electrons to the outside.

The harmful gas treatment facility using the microwave plasma according to the present invention has the following effects.

First, the antenna unit is formed to surround the plasma discharge space, and microwaves are supplied to the plasma discharge space through a plurality of slots, thereby achieving uniform and efficient plasma discharge in the plasma discharge space, thereby improving the treatment efficiency of harmful gases. Not only can it reduce costs, it is economical.

Second, an optimal uniform distribution of incidence in the plasma discharge space can be obtained through the position adjusting unit which can adjust the position of the slot.

Third, after plasma discharge is started by reinforcing interference according to the direction of harmful gas flow, plasma discharge is spread by the fine particles in which harmful substances are decomposed, so that the decomposition power of harmful substances in harmful gases may be further improved. Can be.

1 is a block diagram showing the configuration of a noxious gas treatment facility using a microwave plasma according to an embodiment of the present invention.

FIG. 2 is a front sectional view showing the configuration of the plasma discharge unit of FIG.

3 is a plan sectional view taken along line III-III of FIG. 2.

4 is a diagram illustrating an energy field with respect to a slot position when plasma discharge is generated by the antenna unit of FIG. 2.

FIG. 5 is a plan sectional view taken along the line VV of FIG. 2.

6 is a front sectional view showing another embodiment of the antenna unit in the plasma discharge unit of FIG.

FIG. 7 is a perspective view illustrating the antenna unit of FIG. 2. FIG.

8 is a perspective view illustrating another embodiment of the antenna unit of FIG. 7.

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

First, referring to FIG. 1, a noxious gas treatment facility (hereinafter referred to as a “hazardous gas treatment facility”) using microwave plasma according to an embodiment of the present invention is to treat noxious gas discharged from the process chamber 10. , A microwave generating unit 100, a microwave transmitting unit 200, and a plasma discharge unit 300. Here, the process chamber 10 is a process in which a variety of work processes of a semiconductor or a display is performed, and a process in which ashing, deposition, etching, photography, cleaning, and nitriding is performed, and various process gases and reaction gases This process gas contains harmful substances such as carbon tetrafluoride (CF4) and nitrogen trifluoride (NF3). Reference numeral 30 denotes a scrubbing facility.

The microwave generating unit 100 may include a configuration of a known magnetron as generating microwaves, and a detailed description thereof will be omitted.

The microwave transmitter 200 serves to transfer and supply microwaves generated by the microwave generator 100, and is connected to the plasma discharge unit 300 to connect the microwaves to the plasma discharge unit ( 300 feed to feed.

The microwave transmitter 200 may apply a coaxial cable or a waveguide.

The plasma discharge unit 300 is installed in a pipe through which the noxious gas discharged from the process chamber 10 flows, and receives the microwaves from the microwave transmitter 200 to generate plasma discharge therein. It serves to decompose harmful substances in the harmful gas.

Referring to FIG. 2, the plasma discharge unit 300 is coupled to a vacuum chamber or a foreline, and includes a plasma discharge chamber 310, an antenna unit 320, and a shielding member 330. .

The plasma discharge chamber 310 has a first pipe 41 through which the harmful gas discharged from the process chamber 10 flows and a second pipe 42 through which the harmful gas flows toward the vacuum pump 20. It is installed between the first pipe 41 and the second pipe 42 in communication with the noxious gas passes through the plasma discharge space (1) is formed by the reinforcement interference is formed therein It is. Here, the plasma discharge space 1 may be formed in a cylindrical shape as shown in the drawing, but this may be in various forms such as a rectangular shape in one embodiment, the shape of the plasma discharge chamber 310 and the first Of course, it can be selected in various ways in consideration of the connection structure, the discharge characteristics of the pipe 41 and the second pipe (42).

The antenna unit 320 is installed in the plasma discharge chamber 310, and when microwaves are introduced from the microwave transmitter 200, the antenna unit 320 emits microwaves into the plasma discharge space 1 so that the plasma discharge space ( Plasma discharge is performed in 1).

The antenna unit 320 includes a tubular antenna unit body 321. Referring to FIG. 3, the antenna unit body 321 is disposed to surround the outside of the plasma discharge space 1 to correspond to a flow path of harmful gas when coupled to a foreline or a vacuum chamber. It is formed in an annular shape so as to enclose it so that microwaves are uniformly transferred to the plasma discharge space 1 therein.

The antenna unit body 321 has an internal space 322 into which the microwave is introduced, and an inlet 324 for introducing the microwave into the outer wall.

The antenna unit body 321 is formed with a plurality of slots 323 in which the microwaves of the internal space 322 are emitted on the inner wall facing the plasma discharge space 1. The plurality of slots 323 are formed to be spaced apart from each other toward the plasma discharge space 1 to uniformly discharge the microwaves introduced into the plasma discharge space 1. Descriptions including various details of the slots 323 and various embodiments will be described later.

The shielding member 330 is installed in the plasma discharge chamber 310 so that the outer circumferential surface is spaced apart from the inner surface of the antenna unit 320 in a tubular shape, and ions or electrons for the plasma discharge leak to the outside. It prevents it from becoming. The shielding member 330 is formed to correspond to the plasma discharge space 1, and should be able to transmit the microwave, so that various materials can be applied if it can achieve the above purpose, such as quartz (quartz) or ceramic material Do.

As shown in the drawing, a lower end of the shielding member 330 may be fixed to a fitting portion 311 formed in the plasma discharge chamber 310 to fix its position. However, in one embodiment, the shielding member 330 is positioned in the plasma discharge chamber 310 such that the upper and lower ends of the shielding member 330 are tightly fitted to the inner surface of the plasma discharge chamber 310. Of course, if you can fix a variety of configurations are possible.

The plasma discharge unit 300 may include a tuner (not shown) installed in the plasma discharge chamber 310 to induce an optimal uniform distribution of incidence. The tuner may be applied to various types such as inserting another dielectric material into the microwave or changing impedance by adjusting a space.

Meanwhile, FIG. 4 illustrates an internal energy field (E-field) through which microwaves are transmitted through the slot 323. Referring to the drawing, when the internal energy field A looks at the electric field distribution in the slot 323, it can be seen that the electric field distribution is not uniform. This is because the antenna unit 320 is formed in an annular shape rather than a straight line, and thus the electric field is slightly moved due to the influence of curvature.

Thus, in order to make the electric field distribution constant, the optimum uniform incidence distribution can be induced through the above-described tuner. However, this has a problem in that manufacturing hassle and manufacturing cost increase to install a separate tuner, there is also a difficulty in the operation for the tuner control.

Therefore, the plasma discharge unit 300 may allow the user to directly and intuitively adjust the position of the slot 323 through the position adjusting unit 340, thereby replacing the role of the tuner.

Looking at the position adjustment of the slot 323 through the position adjustment unit 340, first, the antenna unit body 321 is coupled to rotate in the circumferential direction with respect to the plasma discharge chamber (310). In addition, the position adjusting unit 340 is fixedly coupled to the antenna unit body 321 may rotate the antenna unit body 321 along the circumferential direction according to the operator's operation. Thus, the user may change the positions of the slots 323 by rotating the antenna unit 320 along the circumferential direction through the position adjusting unit 340.

Referring to FIG. 5, the position adjusting unit 340 includes a rotation lever 342 coupled to the antenna unit body 321. One end of the rotary lever 342 is coupled to the antenna unit 320, and the other end of the rotary lever 342 passes through an arc-shaped positioning hole 344 formed in the plasma discharge chamber 310, and can be operated by an operator from the outside. It is exposed to the outside so that the user can rotate the antenna unit 320 by holding the other end. Here, the positioning hole 344 is preferably formed in consideration of this, since the microwave does not leak to the outside when the size is 1/4 or less of the microwave wavelength.

As described above, the noxious gas treatment facility may obtain an optimal uniform incident distribution in the plasma discharge space 1 by adjusting the position of the slot 323 through the position adjusting unit 340.

6 is a view showing another embodiment of the antenna unit 320b. Referring to the drawings, the antenna unit 320b is not an antenna unit body 321 is formed as an integral tube, as shown in Figure 2, the antenna is located inside and outside the plasma discharge chamber 310, respectively separated from the inside The sub body 321a is included.

In detail, the antenna unit body 321a is located in the plasma discharge chamber 310 but has an inner wall 3212 located inward with respect to the plasma discharge space 1, and the inner wall 322 is formed. And an outer wall 3211 positioned on the outside to be spaced apart from the 3212.

Here, the inner wall 3212 is erected in the plasma discharge chamber 310 in a cylindrical tube shape so as to surround the cylindrical plasma discharge space (1), the top and bottom are in close contact with the inner surface of the plasma discharge chamber (310). It is fitted. The inner wall 3212 has a plurality of slots 323 formed therethrough to allow the introduced microwaves to be discharged into the plasma discharge space.

The outer wall 3211 is a cylindrical tube shape having a diameter larger than that of the inner wall 3212, and is spaced apart from the inner wall 3212 so as to stand in the plasma discharge chamber 310. 310 is in close contact with the inner surface.

The outer wall 3211 has an inlet 324 through which the microwave is supplied from the microwave transmitter 200. The inlet 324 may be formed in one or a plurality, and may be formed in the middle of the outer wall 3211 or at the top or the bottom thereof as shown in the drawing, and the shape, number, and position thereof may effectively introduce microwaves. This can be done in various ways.

Meanwhile, in the above embodiment, one end of the rotary lever 342a of the position adjusting unit 340a is fixedly coupled to the inner wall 3212 and the middle part of the rotary lever 342a is exposed from the plasma discharge chamber 310.

Hereinafter, the

slots

323 and 323a of the

antenna units

320 and 320a will be described. Prior to this, the

antenna portions

320 and 320a of FIGS. 7 and 8 are shown in a straight tubular shape, but the

antenna portions

320 and 320a are partially enlarged to show a straight line and the shape of the

slots

323 and 323a. It is intended to make the diagram easier to understand.

First, referring to FIG. 7, the slots 323 are spaced apart from each other at equal intervals along the circumferential direction (lengthwise in the drawing) on the inner inner circumferential surface of the antenna unit body 321.

The slots 323 are formed to the inner upper end and the lower end of the antenna unit body 321, and are formed in a direction inclined with respect to the flow direction of the harmful gas. In this case, the inclination angle of the slot 323 may be varied in consideration of the plasma discharge space 1 and the energy field.

Referring to FIG. 8, the slots 323a are formed in a direction perpendicular to the flow direction of the noxious gas. In addition, the slots 323a have a set length and are positioned in a zigzag manner different in height with respect to the flow direction of the noxious gas. The length of the slot 323a may be varied in consideration of the plasma discharge space 1 and the energy field.

On the other hand, although not shown, the slots 323 may be formed in a direction parallel to the flow direction of the harmful gas may be spaced apart along the circumferential direction of the antenna unit body 321.

As described above, the noxious gas treatment facility forms

antenna units

320, 320a, and 320b to surround the plasma discharge space 1, and a plurality of

slots

323, 323a are formed therein so that the microwave is discharged from the plasma discharge space 1. By supplying to the plasma discharge space (1) to achieve a uniform and efficient plasma discharge through this can not only improve the treatment efficiency of harmful gases, but also can reduce the cost can provide an economical effect.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

According to the present invention can be used in the treatment facilities of harmful gases generated during the manufacture of semiconductors or displays.

Claims

In the noxious gas treatment facility using the microwave plasma to treat the noxious gas discharged from the process chamber,

A microwave generating unit for generating a microwave;

A microwave transmitter for transmitting and supplying microwaves generated by the microwave generating unit; And

A plasma discharge unit installed in a pipe through which the noxious gas discharged from the process chamber flows and receiving the microwaves from the microwave transmission unit to generate a plasma discharge therein to decompose noxious substances in the noxious gas; But

The plasma discharge unit,

It is installed between the first pipe through which the harmful gas discharged from the process chamber flows and the second pipe through which the harmful gas flows toward the vacuum pump, and communicate with the first pipe and the second pipe therein. A plasma discharge chamber having a cylindrical plasma discharge space through which gas passes;

The microwave is installed in the plasma discharge chamber and is disposed to surround the outside of the plasma discharge space, and an inner space into which the microwave is introduced is formed and spaced apart from each other toward the plasma discharge space. An antenna unit having a plurality of slots configured to discharge into the plasma discharge space;

And a shielding member installed in the plasma discharge chamber inside the antenna unit to prevent leakage of ions or electrons for the plasma discharge to the outside.
The method according to claim 1,

The plasma discharge unit,

Toxic gas treatment facility using a microwave plasma further comprising a tuner installed in the plasma discharge chamber.
The method according to claim 2,

The plasma discharge unit,

Harmful gas treatment facility using microwave plasma coupled to vacuum chamber or foreline.
The method according to claim 1,

The microwave transmission unit,

Harmful gas treatment facility using microwave plasma including coaxial cable or waveguide.
The method according to claim 1,

The antenna unit,

Toxic gas treatment facility using a microwave plasma is formed in an annular shape to surround the plasma discharge space of the cylinder.
The method according to claim 5,

The slots,

Noxious gas treatment facility using microwave plasma disposed on the inner circumferential surface spaced apart from each other at equal intervals.
The method according to claim 6,

The slots,

Toxic gas treatment facility using a microwave plasma is formed in a direction perpendicular to the flow direction of the harmful gas.
The method according to claim 7,

The slots,

Hazardous gas treatment facility using a microwave plasma located in a zigzag manner different in height with respect to the flow direction of the harmful gas.
The method according to claim 6,

The slots,

Toxic gas treatment facility using a microwave plasma is formed in a direction inclined with respect to the flow direction of the harmful gas.
The method according to claim 6,

The slots,

Toxic gas treatment facility using a microwave plasma formed in a direction parallel to the flow direction of the harmful gas.
The method according to claim 1,

The antenna unit is rotatably installed in the circumferential direction with respect to the plasma discharge chamber,

The plasma discharge unit further comprises a position adjusting unit connected to the antenna unit to allow a user to rotate the antenna unit along the circumferential direction to change the positions of the slots.
The method according to claim 11,

The position adjusting unit,

One end is coupled to the antenna portion, the other end is formed to be exposed to the outside through the arc-shaped positioning hole formed in the plasma discharge chamber, the user rotates to hold the other end to rotate the antenna unit Harmful gas treatment facility using microwave plasma including a lever.