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:
Dec. 31, 2013
Filed:
May. 01, 2012
Applicants:
Xinye Liu, Sunnyvale, CA (US);
Chiukin Steven Lai, Sunnyvale, CA (US);
Inventors:
Xinye Liu, Sunnyvale, CA (US);
Chiukin Steven Lai, Sunnyvale, CA (US);
Assignee:
Novellus Systems, Inc., Fremont, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
C23F 1/08 (2006.01); H01L 21/306 (2006.01); H01L 21/67 (2006.01);
U.S. Cl.
CPC ...
C23F 1/08 (2013.01); H01L 21/67069 (2013.01);
Abstract
Etching of nitride and oxide layers with reactant gases is modulated by etching in different process regimes. High etch selectivity to silicon nitride is achieved in an adsorption regime where the partial pressure of the etchant is lower than its vapor pressure. Low etch selectivity to silicon nitride is achieved in a condensation regime where the partial pressure of the etchant is higher than its vapor pressure. By controlling partial pressure of the etchant, very high etch selectivity to silicon nitride may be achieved.