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:
Aug. 11, 1998
Filed:
Jan. 13, 1997
Minoru Harada, Fujisawa-shi, Kanagawa-ken, JP;
Ryoichi Shinjo, Yokohama-shi, Kanagawa-ken, JP;
Manabu Tsujimura, Yokohama-shi, Kanagawa-ken, JP;
Rempei Nakata, Kamakura-shi, Kanagawa-ken, JP;
Kunihiro Miyazaki, Tokyo, JP;
Naruhiko Kaji, Yokohama-shi, Kanagawa-ken, JP;
Yutaka Nakano, Ichikawa-shi, Chiba-ken, JP;
Other;
Abstract
Ozonizer (10) which supplies a feed gas to ozone generating cell (11) under application of a high voltage and which delivers an ozone gas through an ozone gas transport path (consisting of pipes (14) and (15)) as it has been generated in said ozone generating cell (11) is characterized in that the ozone gas transport path is furnished with means for removing at least one of NOx, HF and SOx (in the drawings, the means is for removing NOx) and that the ozone gas from the ozone generating cell (11) is passed through said removing means, whereby at least one of NOx, HF and SOx in said ozone gas is removed before it is delivered to a subsequent stage. The product ozone is not contaminated with Cr compounds at all or insufficiently contaminated to cause any practical problems in the fabrication of highly integrated semiconductor devices. Alternatively, ozonizer (10) which comprises an ozone generating cell (11) having an inlet (8) for supplying a feed gas, high voltage applying means (35) and an outlet (29) for discharging the ozone generated, and ozone delivery paths (30) and (31) for delivering the generated ozone is characterized in that oxygen (1) supplemented with 10-20 vol % of carbon dioxide and/or carbon monoxide (2) is used as the feed gas. The thus produced ozone is significantly low in the level of Cr compounds and, hence, can suitably be used in the formation of metal oxides, in particular, silicon oxide.