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:
Jul. 08, 1997
Filed:
May. 22, 1996
Naser Mahmud Chowdhury, Orefield, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A method and apparatus for storing ultra high purity non-cryogenic liquefied compressed gases, such as ammonia (NH.sub.3), and delivering a vaporized gaseous product from those liquefied gases for semiconductor processing applications. The delivery method includes withdrawing and heating gaseous product from a storage vessel containing the liquefied compressed gas, and then piping the heated gas through the liquid contained in the storage vessel in a heat exchange fashion. The heat exchange with the liquid inside the vessel induces boiling to maintain a vaporized gaseous product under a minimum positive pressure in said vessel. After liberating its heat, the gaseous product is delivered to a semiconductor manufacturing point of use.