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:
Sep. 02, 1997
Filed:
Apr. 24, 1996
Siemens Aktiengesellschaft, Munich, DE;
Abstract
In a method for the selective removal of SiO.sub.2 relative to semiconductor materials and/or metal, a specimen to be processed and containing SiO.sub.2 is placed into a chamber having at least one gas admission opening and one gas outlet opening. Using controllable valves at the gas admission opening, dosed quantities of hydrogen fluoride gas and water vapor are admitted into the chamber. These gasses proceed to the SiO.sub.2 in a specimen in a quantity adequate for etching. However, the quantities of these gasses are limited such that a condensation of the water vapor to form liquid water on the specimen during the etching event is avoided. An etching event is then implemented. Water vapor that arises as a reaction product during the etching is eliminated through the gas outlet opening before the occurrence of condensation and, simultaneously, an inert gas is admitted into the chamber through the gas admission opening. These steps are repeated as needed.