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:
Oct. 09, 2001
Filed:
Mar. 28, 2000
Robert T. Fayfield, St. Louis Park, MN (US);
John M. Heitzinger, St. Louis Park, MN (US);
FSI International, Inc., Chaska, MN (US);
Abstract
Apparatus and method for direct delivery of enabling chemical gas from a liquid source and of HF gas in a hydrogen fluoride/enabling chemical based cleaning or etching process, such as a silicon dioxide film etching process. The liquid enabling chemical is temperature controlled to generate a vapor pressure which is sufficient to operate a mass flow controller at a desired processing pressure without a carrier gas. Prior to entering the process chamber, the enabling chemical gas is pre-mixed with HF and optionally, a carrier gas, all of which are supplied at flow rates independent of each other. By controlling the vapor pressure of the solvent in this way, solvent/HF/carrier mixtures which are not physically possible with carrier gas systems are attainable allowing access to a larger process space.