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:
Apr. 08, 2003
Filed:
Nov. 30, 2001
Applicant:
Inventors:
Russell Westerman, Largo, FL (US);
Christopher Constantine, Safety Harbor, FL (US);
Assignee:
Unaxis USA Inc., St. Petersburg, FL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 9/00 ;
U.S. Cl.
CPC ...
G03F 9/00 ;
Abstract
An embedded attenuated phase shift mask (“EAPSM”) includes an etch stop layer that can be plasma etched in a process that is highly selective to the underlying quartz substrate. Selectivity to the underlying quartz maintains a desired 180 degree phase shift uniformly across the active mask area. Conventional plasma etching techniques can be utilized without damage to the underlying quartz substrate. Alternatively, the etch stop layer comprises a transparent material that can remain intact in the mask structure.