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:
Nov. 02, 2004
Filed:
Dec. 21, 2001
Applicant:
Inventor:
Jeffrey E. McAninch, Livermore, CA (US);
Assignee:
Therma-Wave, Inc., Fremont, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N 2/155 ; G01N 2/147 ; G01N 2/121 ;
U.S. Cl.
CPC ...
G01N 2/155 ; G01N 2/147 ; G01N 2/121 ;
Abstract
A purge system for an optical metrology tool is disclosed. The metrology tool includes an optics plate for supporting the measurement optics. A movable stage supports a wafer below the optics plate. Inert purge gas is injected between the lower surface of the optics plate and the upper surface of the wafer. The gas flow functions to stabilize and homogenize the ambient in the measurement region. The gas flow also serves to clear the measurement area of absorbing species which is particular useful for measurements using vacuum ultraviolet light.