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. 16, 2000
Filed:
Mar. 03, 1998
Applicant:
Inventors:
Joe G Hoffman, Cardiff, CA (US);
R Scot Clark, Fallbrook, CA (US);
Assignee:
Air Liquide America Corporation, Houston, TX (US);
Primary Examiner:
Int. Cl.
CPC ...
C01B / ;
U.S. Cl.
CPC ...
423483 ; 423488 ;
Abstract
A system for purification and generation of hydrofluoric acid on-site at a semiconductor device fabrication facility. An evaporation stage (optionally with arsenic oxidation) is followed by a fractionating column to remove most other impurities, an Ionic Purifier column to suppress contaminants not removed by the fractionating column, and finally the HF Supplier (HFS).