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:
Jun. 27, 1995
Filed:
Aug. 31, 1993
Yao-En Li, Buffalo Grove, IL (US);
John Rizos, Frankfort, IL (US);
American Air Liquide, Inc., Walnut Creek, CA (US);
Abstract
A purification method and apparatus for creating ultra-purity chemicals for semiconductor processing. The purification method includes a step of expanding an ESG chemical through an orifice (17) inside a condenser (21) to a partial condensed state for removing impurities from ESG chemical. During the expansion step, the higher boiling point impurities remain in the liquid phase and the impurities in the vapor phase are removed at least in part by a scavenging technique. After purification, the ultra-purified gas is transferred to a semiconductor manufacturing operation (24). The manufacturing operation includes both dry and wet processes. The method may also be integrated into a large volume on-site purification system (30), on-line point of use purifier (50), or small volume trans-filling purification system (70).