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. 16, 2002
Filed:
Oct. 03, 2000
Leping Li, Poughkeepsie, NY (US);
James Albert Gilhooly, Saint Albans, VT (US);
Clifford Owen Morgan, III, Burlington, VT (US);
Cong Wei, Poughkeepsie, NY (US);
Chienfan Yu, Highland Mills, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Detection of the endpoint for removal of a target film overlying a stopping film by removing the target film with a process that selectively generates a chemical reaction product (for example, ammonia when polishing a wafer with a nitride film in a slurry containing KOH) with either the target or stopping film, and monitoring the level of chemical reaction product as the target film is removed. The reaction product is extracted as a gas from the slurry and monitored using a threshold photoionization mass spectrometer.