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:
May. 25, 2004
Filed:
Jun. 26, 2002
Applicant:
Inventors:
Martin Hostalek, Darmstadt, DE;
Werner Büttner, Darmstadt-Arheilgen, DE;
Rolf Hafner, Egelbach, DE;
Chih-Peng Lu, Taipei, TW;
Ching-Jung Kan, Nan-Tou, TW;
Ekkehart Seitz, Seeheim-Jungenheim, DE;
Ernst Friedel, Darmstadt, DE;
Assignee:
Merck Patent GmbH, Darmstadt, DE;
Primary Examiner:
Int. Cl.
CPC ...
C01B 1/769 ; C01B 1/774 ; C01B 1/782 ; C01B 1/790 ;
U.S. Cl.
CPC ...
C01B 1/769 ; C01B 1/774 ; C01B 1/782 ; C01B 1/790 ;
Abstract
The invention relates to a novel method for producing high-purity sulfuric acid for use in the semiconductor industry. The method comprises the addition of a hydrogen peroxide solution to an engineered oelum in order to reduce the SO concentration, evaporation of the SO and separation of acid traces. The high-purity SO is then enriched with inert gas and the SO is absorbed into sulfuric acid.