The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 20, 1999
Filed:
Jun. 23, 1997
Kenji Otsuka, Kanagawa, JP;
Hiroshi Waki, Kanagawa, JP;
Yoshio Yamashita, Kanagawa, JP;
Satoshi Arakawa, Kanagawa, JP;
Toshiya Hatakeyama, Kanagawa, JP;
Japan Pionics Co., Ltd., Tokyo, JP;
Abstract
A dust removing apparatus equipped with a back washing mechanism and a dust removing method for removing solid silica fine powder contained in a gas discharged from a semiconductor producing step of a single-wafer processing atmospheric pressure CVD apparatus without causing problems caused by the increase of a pressure loss and by a pressure fluctuation, wherein filter elements each having a ratio of a surface area of a primary side of a filter membrane to an apparent external surface area of the filter element of from 1 to 5 is used, gas jetting nozzle(s) for back washing is formed in the secondary side of the filter element, back washing is not carried out during filtration in the filter element and at or after changing the processing of a wafer in the CVD apparatus, back washing is carried out to blow down the silica fine powder accumulated on the primary side of the filter membrane.