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EP0303368A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Treating waste gas

Assignee: Ebara Corp
•
Filing: 1988-07-26
•
Granted: —
•
Expires: 2008-07-26
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Abstract

Abstract A method of treating a waste gas containing at least boron trichloride and chlorine comprises first treating the waste gas with a treating agent containing a magnesium compound by dry process and then treating the waste gas with a treating agent containing a calcium compound by dry pro­cess. Thus, it is possible to remove efficiently a chloride and chlorine containing gas from waste gas discharged from dry etching process or other manufacturing process in the semiconductor industry. In addition, it is possible to reduce the amount of treating agent used, lengthen the treating agent replacing cycle, and facilitate the maintenance of the system.

Inventors

  • 👤 Akira Fukunaga
  • 👤 Yoichi Mori

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 22:08
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/68

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 107 words
A method of treating a waste gas containing at least boron trichloride and chlorine, comprising first treating the waste gas with a treating agent containing a magnesium compound packed in a tower and then treating said waste gas with a treating agent containing a calcium compound packed in the same or another tower, the temperature within said tower being in the range of from about 20°C to about 80°C, the waste gas being passed through said tower under a pressure of from about 0.9 atoms to about 2 atoms, and the particle size of the treating agents being about 0.3 mm to about 5.0 mm in diameter.
Claim 2
Independent Claim 107 words
A method of treating a waste gas containing at least boron trichloride and chlorine, comprising first treating the waste gas with a treating agent containing a magnesium compound packed in a tower and then treating said waste gas with a treating agent containing a calcium compound packed in the same or another tower, the temperature within said tower being in the range of from about 20°C to about 80°C, the waste gas being passed through said tower under a pressure of from about 0.9 atoms to about 2 atoms, and the particle size of the treating agents being about 0.3 mm to about 5.0 mm in diameter.
Claim 3
Dependent Claim 47 words
The method of Claim 1, wherein said magnesium com­pound is selected from the group consisting of magnesium hydroxide, magnesium oxide, magnesium carbonate and a mixture thereof, while said calcium compound is selected from the group consisting of calcium hydroxide, calcium oxide, calcium carbonate and a mixture thereof.
Claim 4
Dependent Claim 31 words
The method of Claim 1 or 2, wherein said waste gas is discharged from a chemical dry etching step using a chloride and/or chlorine containing gas in a semiconductor manufacturing process.

References Cited (Backward Citations)

CH559573A5 Cited
DE3308927A1 Cited

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