JP2000126546A - Gas constituent accumulation electrode structure in unreacted gas cleaning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solidification accumulation electrode wherein exchange life of a solidification accumulation electrode (plasma electrode and ground electrode) is significantly elongated, disposal after exchange is compatible with environmental preservation and easy treatment can be performed. SOLUTION: In an unreacted gas cleaning apparatus wherein a plasma electrode 2 and a ground electrode 4 are helically formed and the two electrodes 2, 4 are arranged alternately, and the plasma electrode 2 and the ground electrode 4 are connected to a high frequency source and an inner wall of an apparatus, respectively, and an excess discharge gas of a semiconductor manufacturing system employing a CVD method and a plasma gas are supplied between the two electrodes 2, 4 and a coagulation constituent and a poisonous constituent contained in the gases are made to accumulate on the electrodes for removal, the plasma electrode 2 and the ground electrode 4 are formed by a conductive sheet made of a glass fiber sheet having a surface coated with a conductive substance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION CVD (Chemical Vapor Deposition)
For example, when a semiconductor is manufactured by the method described above, the unreacted process gas discharged includes a condensed component and a toxic gas. The present invention relates to an improvement in an apparatus for removing these condensed components and the like.

[0002]

2. Description of the Related Art A surplus of a process gas used in manufacturing a semiconductor by a CVD method or the like is discharged to the outside as an exhaust gas, and 90% or more of the exhaust gas is decomposed by HF plasma and deposited on a trap. Captured. However, the surplus exhaust gas that escaped the capture is cooled in the piping and the vacuum pump, and the condensed components contained therein condense, causing clogging of the piping and the vacuum pump, causing a stagnation of semiconductor production. Also reacts with the oil in the vacuum pump,
It also causes the performance of the vacuum pump to deteriorate. In addition, this surplus exhaust gas contains toxic components,
It cannot be discarded as it is. As a device to remove condensed components and toxic components contained in this excess exhaust gas,
As shown in FIG. 2, a plasma electrode 2 formed by spirally winding an aluminum plate is connected to a high-frequency power source 3, and a ground electrode 4 similarly formed by spirally winding an aluminum plate is connected to the inner wall of the device. 2 and the ground electrode 4 are arranged alternately, and solidification components and toxic components contained in the excess exhaust gas are solidified and deposited on the plasma electrode 2 and the ground electrode 4 to be removed.

[0003]

However, the unreacted gas purifying apparatus for removing condensed components and toxic components contained in the surplus exhaust gas includes a portion of the plasma electrode 2 and the ground electrode 4 near the intake port and an exhaust gas. Sediment accumulates near the mouth (especially at low temperatures). Therefore, there is a disadvantage that the portion close to the intake port and the portion close to the exhaust port are clogged though the other portions are not clogged, and the device becomes immediately unusable. Further, since the deposits adhered to the plasma electrode 2 and the ground electrode 4 contain toxic substances such as arsenic, when the plasma electrode 2 and the ground electrode 4 (solidification deposition electrode) are discarded, the Must be taken care of, and the processing is troublesome.

Accordingly, the present invention is to provide a solid deposition electrode which is capable of prolonging the replacement life of the solid deposition electrode (plasma electrode and ground electrode), and which is environmentally friendly and can be easily processed when disposed after replacement. The purpose is to provide.

[0005]

That is, according to the present invention, a plasma electrode and a ground electrode are alternately arranged, a plasma electrode is connected to a high-frequency power supply, and a ground electrode is connected to an inner wall of the apparatus. In an unreacted gas purifier that supplies surplus exhaust gas and plasma decomposition gas from a semiconductor manufacturing system by depositing and removing condensed components and toxic components contained in these gases on the electrodes, the surface of the glass fiber sheet is removed. The plasma electrode and the ground electrode are formed by a conductive sheet coated with a conductive material.

[0006]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged sectional view of a solidification deposition electrode,
FIG. 2 is a schematic diagram of an unreacted gas purifying apparatus of a semiconductor manufacturing system by a CVD method. Reference numeral 1 denotes an unreacted gas purification device, which is a spiral plasma electrode 2 connected to a high-frequency power supply 3.
And spiral ground electrodes 4 are alternately arranged in the same manner as the plasma electrode 2 and housed in the deposit removing container 5. The surplus exhaust gas is supplied to the unreacted gas purifying device 1 through the nitride reactor 6 and the water removing device 7 via the route pump 8. Then, after coming into contact with the plasma electrode 2 and the ground electrode 4, the gas is exhausted from the exhaust port of the unreacted gas purification device 1 through the pipe 9 and the vacuum pump 10 connected thereto. As shown in FIG. 1, the plasma electrode 2 and the ground electrode 4 are formed by coating a surface of a glass fiber sheet 11 with a conductive substance 12 by a plasma sputtering method or the like and then woven into a cloth, or a glass fiber sheet. The surface of the cloth is coated with a conductive substance by a plasma sputtering method and used as a conductive sheet.

[0007] The surface area of the plasma electrode 2 and the ground electrode 4 formed as described above is significantly increased as compared with a metal plate. About 5 times)
Therefore, the area in which the condensed components and toxic components contained in the surplus exhaust gas can be solidified and deposited increases, and the exchange life of the plasma electrode 2 and the ground electrode 4 can be greatly extended. In addition, the efficiency of heat radiation is improved due to the increase in the surface area of the plasma electrode 2 and the ground electrode 4, and the plasma electrode 2 and the ground electrode 4 accumulate deposits in portions other than the portion near the intake port and the portion near the exhaust port. As a result, the life of the unreacted gas purifying device 1 is further extended. Then, when a large amount of deposits accumulate on the plasma electrode 2 and the ground electrode 4 and reach the replacement life, the plasma electrode 2 and the ground electrode 4 are removed and replaced with a new one, and the old one is replaced with an arc plasma blast furnace. After melting into a ceramic mold and solidifying it, it becomes a glass brick, so that toxic components of waste can be sealed in the molten glass and discarded without causing environmental pollution.

In the above embodiment, the plasma electrode 2
Is connected to the high-frequency power supply 3, but depending on the surplus exhaust gas, only cooling may be required in some cases. In such a case, the plasma electrode 2 and the ground electrode 4 may be cooled with liquid nitrogen or the like without connecting the plasma electrode 2 to the high frequency power supply 3.

In the above embodiment, the plasma electrode 2
Although the woven cloth is used for the ground electrode 4, when a glass fiber having a small diameter is used, a nonwoven cloth may be used. The weaving of the woven fabric is not limited, but if the woven fabric is tightly packed, it is difficult to accumulate the sediment. The high-frequency power supply 3 includes both an HF power supply and an RF power supply. In the above embodiment, the plasma electrode 2 and the ground electrode 4 are formed in a spiral shape. However, the present invention is not limited to this.
Alternatively, the ground electrode 4 may be formed in a comb-like shape and opposed to each other.

[0010]

In summary, according to the present invention, the plasma electrode and the ground electrode are formed of a conductive sheet formed by coating a conductive material on the surface of a glass fiber cloth. The area is extremely increased, and the area where the condensed components and toxic components contained in the surplus exhaust gas can be solidified and deposited increases. In addition, the efficiency of heat radiation is improved due to the increase in the surface area, and the plasma electrode and the ground electrode combine with the effect that deposits accumulate in portions other than the portion near the intake port and the portion near the exhaust port. The purifier has a longer life.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a plasma electrode.

FIG. 2 is a schematic diagram of an unreacted gas purification device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Unreacted gas purifier 2 Plasma electrode 3 High frequency power supply 4 Ground electrode 11 Glass fiber sheet 12 Conductive substance

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D002 AA40 AC10 BA07 BA13 CA20 DA70 EA07 GA02 GB02 GB04 HA10 4G075 AA37 BC04 CA47 DA02 EB41 4K030 FA04 KA15 KA49 LA15 5F045 AA08 BB20 EB05 EG07 EH04 EH08

Claims (1)

[Claims] 1. A plasma electrode and a ground electrode are alternately arranged, a plasma electrode is connected to a high-frequency power source, and a ground electrode is connected to an inner wall of the apparatus. In an unreacted gas purifier that supplies plasma decomposition gas and removes condensed and toxic components contained in these gases by depositing them on the electrodes, a conductive sheet coated with a conductive material on the surface of a glass fiber sheet is used. And a gas component deposition electrode structure comprising the plasma electrode and the ground electrode.