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. 13, 2010
Filed:
Oct. 27, 2006
Applicant:
Visvamohan Yegnashankaran, Cupertino, CA (US);
Inventor:
Visvamohan Yegnashankaran, Cupertino, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/66 (2006.01); G01N 21/86 (2006.01);
U.S. Cl.
CPC ...
Abstract
Minute materials which can be undesirably left on the backside of a semiconductor wafer are detected by scanning the semiconductor wafer with an infra-red (IR) light following the completion of a process step that forms and then selectively removes a material from the top surface of the wafer. Any detected material can then be removed from the backside of the wafer to ensure that that backside of the wafer is clean and flat.