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:
Dec. 08, 1998
Filed:
Jul. 01, 1996
Applicant:
Inventors:
Joe G Hoffman, Cardiff, CA (US);
R Scott Clark, Fallbrook, CA (US);
Assignee:
Startec Ventures, Inc., Fallbrook, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ; B01D / ;
U.S. Cl.
CPC ...
203 13 ; 203 40 ; 423484 ; 423488 ; 202158 ; 202161 ; 202172 ; 202200 ;
Abstract
Highly purified ammonia for use in semiconductor manufacturing is prepared on-site by drawing ammonia vapor from a liquid ammonia reservoir, passing the vapor through a filter capable of filtering out particles of less than 0.005 micron in size, and scrubbing the filtered vapor in a high-pH aqueous scrubber.